Tales from the Golden Age: The Telescopes of Sir Patrick Moore (1923-2012)

Sir Patrick Moore(1923-2012), seen here standing beside his 5 inch f/12 Cooke refractor. Image credit: Martin Mobberley.

The late Sir Patrick Moore(1923-2012) needs no introduction to the astronomical community. A towering figure for over half a century, he was adored (and sadly, disliked by a few) by a legion of fans the world over as the eccentric, silver tongued English writer and presenter of the longest running television series in history; BBC Sky at Night; with an encyclopedic knowledge of astronomy. Inexplicable to Americans, gin guzzling, pipe smoking, xenophobic, insensitive, incomprehensible to some, inflexible, irksome, he was also warm, passionate, generous to a fault, loyal to his friends, an institution in his own right, and a law unto himself!

As a fan of Sir Patrick from childhood, I bought, borrowed and read many of his books. He was the person who first sparked my interest in astronomy, and even as my hobby turned into a profession of sorts, he always returned my phone calls and promptly responded to my letters in his unique way; using an old fashioned type writer. But while there was hardly a telescope, amateur or professional, that the great man didn’t peer through during his prolific career, it pays to take a closer look at the kinds of instruments he personally owned.

Expressing an interest in the night sky since he was knee high to a proverbial grasshopper, Moore was lucky enough to live right across the road from the tycoon, Frederick J. Hanbury, at East Grinstead, West Sussex, who had a lavishly equipped observatory erected on his estate, with a 6.1 inch Cooke refractor as its Pièce de résistance. But Hanbury himself was far too busy to run the observatory from day to day, instead hiring a full time assistant, William Saddler Franks(1851-1935), to  demonstrate at the telescope, and tasked with entertaining Hanbury’s frequent guests and business acquaintances with the glories of the Sun, Moon, planets and distant stars. On quieter evenings, Franks would return to more routine work, measuring double stars with a filar micrometer and completing sketches of what he saw at the eyepiece. Franks struck up a strong bond of friendship with the young Patrick Moore and it was here that he probably enjoyed his first views of the night sky through a telescope.

Acting on a recommendation he received from the Dr. W.H. Steavenson (a prominent member of the British Astronomical Association in those days), Patrick, accompanied by his mother, took a train up to London to visit the workshops of the leading telescope maker for amateurs in the country; Broadhurst Clarkson, where he acquired his first proper instrument; a 3 inch achromatic refractor for the princely sum of £7 10 shillings. This was quite a bit of cash to splash out for the time. Martin Mobberley, writing in his excellent biography of Moore: It Came From Outer Space Wearing an RAF Blazer! estimates that it was the equivalent of about two weeks wages for an ordinary working man. But a fine telescope it was nonetheless!

Sir Patrick Moore’s newly restored 3″ f/12 Broadhurst Clarkson refractor.

Already almost a quarter of a century old (circa 1910 vintage), the shining, rolled brass tube, housed a very well figured 3 inch object glass with a focal length of three feet (so f/12). The instrument has a smooth, single wheel focuser (like all small refractors of the era) and came equipped with a few eyepieces for low, medium and high power work. Its Achilles’ Heel though, as Moore soon found out to his chagrin, was the flimsy ‘pillar and claw’ mount that accompanied it. While it looked rather ornate in the corner of a stately indoor space, it was next to useless for astronomical purposes. Moore referred to it discontentedly as the ‘blancmange’ but it was quickly replaced by a much more sturdy tripod of extendable height, at an additional cost of 30 shillings.

A rescued Broadhurst Clarkson 3″ f/12 achromat (1940s vintage), field tested by the author.

Though this author has not had the privilege of looking though Sir Patricks particular 3” f/12 achromatic telescope, he has sampled, as it were, a ‘system of particles‘ centred on an 80mm f/11 achromat, but also from shorter and longer ‘particles‘. But more specifically, this author partially restored an essentially identical instrument to Moore’s telescopic alma mater during the autumn of 2012, where he spent a few days testing its optics. The instrument produced very pleasing, high contrast images of the daytime landscape, with very little secondary spectrum. Night time tests showed that stars presented as tight pinpoints of light with almost identical Fraunhofer diffraction rings both inside and outside focus. Lunar views were crisp and sharp at powers up to approximately 150x, and a suite of suitable double stars were also well resolved at the highest magnifications employed. In short, this author was confident that such a telescope would show any experienced observer what the best modern 3 inch refractor could present.

Moore used the instrument extensively, where it presented him with all the showpieces of the night sky. This much is abundantly clear from his many references to the 3 inch in his voluminous published writings of later times. It was with this telescope that he learned his way around the battered face of the Moon; a study that would propel the young man to international notoriety in the years to come.  Indeed, he used his 3 inch Broadhurst Clarkson to suggest his first paper to the BAA entitled, Small Craterlets in the Mare Crisium, in 1937, at the tender age of 14! And while there is no official record of such a presentation, Moore most definitely studied this lunar region with his small telescope. Mobberley, who had the pleasure of examining Moore’s observational records show that while he demonstrated almost no artistic flare at school, his drawings of various lunar features made with the 3 inch and dated to 1940 show that he had, by that time, developed considerable ability to draw complex structures at the eyepiece. And though he would go on to make rapid progress within the ranks of the BAA in the post-war years, the 3 inch Broadhurst Clarkson was probably the only telescope he personally owned right up until about 1950!

While many astronomers consider the Moon to be a form of light pollution, Sir Patrick maintained a lifelong passion for exploring our nearest neighbour in space. For over half a century, astronomers working with some of the largest telescopes in the world were busy photographing its surface, but the relative insensitivity of photographic emulsions during that era meant that there was always visual work to do in fleshing out the finest selenographic details. This kind of work was ideally suited to moderately sized instruments that could be pressed into service fairly frequently. No doubt, it was this possibility that influenced Sir Patrick’s next telescope acquisition, and it would come from his new mentor, Hugh Percy Wilkins(1896–1960), a Welsh–born mechanical engineer and amateur astronomer.

From 1946 to 1956, Wilkins served as the Director of the Lunar Section of the BAA and it was through its meetings and publications that Moore became attracted to Wilkins’ work. Indeed, in many ways, Wilkins and Moore were very much alike. Both were extroverted, more than a little odd, and passionate about everything pertaining to our natural satellite. Wilkins had moved from his native Wales to put down roots at 35 Fairlawn Avenue, Bexleyheath, Kent, only 25 miles north of Moore’s abode at Glencathara, East Grinstead. There the young astronomer enjoyed many fine views through Wilkins’ 12.5 Newtonian. Over the years, Wilkins had produced truly colossal Moon maps, starting with a 24” completed in 1924, and, with the help of Moore, culminating with a 300” lunar map in 1951 and which was considered by some to represent “the culmination of the art of selenography prior to the space age.”

Sir Patrick looking through his trusty 12.5 inch f/6 Newtonian reflector nicknamed ‘Oscar.’ Early 1950s. Image credit: Martin Mobberley.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

When Wilkin’s decided to acquire a larger instrument (a 15.25 inch Newtonian), Moore, having tried and trusted the 12.5 inch, had no hesitation in buying it off him.  With a focal length of 72 inches (so f/6), its primary mirror was made by the noted British telescope maker, Henry Wildey(1913–2003). This new telescope, which Moore affectionately referred to as ‘Oscar,’ was mounted on a heavy duty altazimuth mount equipped, specially designed Ron Irving(1915–2005) with good slow motion controls. And while Moore intended to upgrade the mount to equatorial mode at some point in the future, the astronomical (pun intended) cost that it would incur stopped that project dead in the water. Indeed, ‘Oscar’ was to remain on its original altazimuth mounting for the remainder of Moore’s long life, housed inside a double–ended roll off shed at his home at East Grinstead. This 12.5 inch was arguably the instrument Moore used most often throughout his career to produce some of his finest work.

Oscar in old age, being inspected by the crew of BBC Sky at Night. Image credit: Martin Mobberley.

 

To say that Sir Patrick Moore was more of a showman, as some of his more envious contemporaries would have claimed, than an observer, would be very far from the truth. One need look no further than his observing logbooks to see that not only was he a regular observer, but he was also capable of great bouts of stamina, well above and beyond the efforts of many amateurs today. One example this author stumbled upon was an entry he made in March 1967 while he was serving as Director of Armagh Planetarium, Northern Ireland. These notes, which are very neat and tidy, show that, despite having access to a very good 10 inch Grubb refractor at the Observatory annexed to the Planetarium, he was using Oscar and a 8.5 inch With Browning Newtonian (acquired sometime in the early 1960s), both of which he had shipped over to Northern Ireland, to make some excellent Jupiter observations, recoding details of both the Jovian disk as well as several transits of the Galilean satellites watched continually over a complete rotation of the planet (so about 10 hours)!

To be continued………..

De Fideli.

Tales from the Golden Age: Excerpts from the Life of Leslie C. Peltier.

The distinguished American amateur astronomer, Leslie C. Peltier (1900 – 1980).

 

 

 

 

 

 

 

 

Out of whose womb came the ice?

and the hoary frost of heaven, who hath gendered it?

The waters are hid as with a stone,

and the face of the deep is frozen.

 Canst thou bind the sweet influences of Pleiades,

or loose the bands of Orion?

Canst thou bring forth Mazzaroth in his season?

or canst thou guide Arcturus with his sons?

Knowest thou the ordinances of heaven?

canst thou set the dominion thereof in the earth?

Job 38:29-33.

Picture a time before radio, before television, computers, cell phones, a time before electricity, running water and central heating. Could anyone possibly be happy in such a world? Could such a time ever be said to be idyllic? After learning of the life of Leslie Copus Peltier, one can begin to understand why that could well be so.

Born in the small town of Delphos, Ohio, on the second day of January 1900, Peltier spent almost his entire life on the family farm called Brookhaven, that was worked by his ancestors since the time before the Civil War. Such rural families formed the basic unit of civilised society. They were self sufficient, hardworking and God fearing. The 50 acres of land was fertile, watered by the nearby Auglaize River, and brought forth crops of corn, wheat and oats in rotation before being revitalised by clover planting. Fresh vegetables were sown, grown and harvested, as were succulent strawberries, cultivated on two acres of land,  which proved to be a valuable source of income for the family every summer.  A half dozen dairy cattle gorged on the fresh blades of grass springing up along the river bank, providing wholesome milk both to drink and to make cream, butter and cheese with. Poultry provided a fresh supply of eggs and a small herd of hogs gave the family a steady supply of ham and sausage. Nothing was wasted. Any surplus foodstuffs were canned, salted or smoked for consumption through the long winters.

But while life was hard, there was a palpable sense of fraternity among the farming communities of Northwestern Ohio, centred as they were in the local Church hall, where meetings were convened to discuss matters of public concern. Both Leslie’s parents were regular Church goers and taught Sunday School to the children. In his famous autobiography; Starlight Nights; the Adventures of a Stargazer; Peltier describes his parents as “living harmoniously” together and this in turn brought happiness and stability to the entire family. “Blessed are they who are raised on a farm,” he was to prophetically write many years later.

The Peltiers were voracious readers. This was a family that knew the Bible, the great classic works of American literature and the immortal poems and plays of Shakespeare. They were also the proud owners of some of the earliest renditions of the Encyclopedia Britannica. Any news from the outside world arrived twice a week in the form of a newspaper, week in and week out. Living so close to nature, it is small wonder that Peltier had a highly developed spiritual sense, which spilled over into his eloquent writings in later life. He got his first encounter with the shining stars at age five, when his mother showed him the brilliant Pleiades which captivated the young boy. And two years later, his father pointed out the mighty planet Jupiter beaming its still yellow light across the sable depths of space. In 1910, two bright comets graced the skies over Ohio. First came 1910a in January, followed by the faithful return of Halley’s Comet in May which enthralled him. But it was not until Peltier was 15 years old that the stars of heaven really began to call him.

Though the family library was a veritable mine of information on just about any topic, there was nothing he could find there that could fully assuage the questions that bubbled up in his fecund mind. But these were sated by a visit to the school library, where he picked up a copy of Martha Evans Martin’s classic work, The Friendly Stars, which enabled the boy to begin to identify, first the brightest stellar luminaries like Vega, Deneb, Altair and Arcturus, but as the weeks and months went by, the stars of lesser glory also, together with the shapes of the constellations to which they were assigned. According to his autobiography, Peltier spent nearly two years learning his way around the night sky. Fascinated by how the fixed stars in the firmament mapped out the passage of time, he would rise at ungodly hours of the night just to get a glimpse of how the sky would look at more respectable hours in the month’s ahead. It was his time machine. And all the while, this great journey of celestial exploration was done entirely without any optical aid. He had, as yet, no telescope to extend the reach of his naked eye. But that was something he would have to remedy sooner rather than later.

Between 1915 and 1917, Leslie attended the local High School and it was there, during his middle year, that he had his first encounter with a telescope. It was not very big but to Leslie it was all he could think about! There it was, boldly displayed in the physics lab, like some kind of museum piece, under lock and key inside a fortress of glass. And while he was permitted to handle the instrument by his instructor, his request to borrow it for a spell was firmly refused. Peltier never divulges the reasons for this rebuttal; perhaps his superiors thought he would damage it or some such, but the event had a somewhat unexpected effect on the young man. Instead of dragging his feet and sulking, it only deepened his resolve to save up and buy one with his own money.

And luckily there was a way of earning coin on the farm. The month of June was high season for picking strawberries at Brookhaven and the boy put his back into filling the crates with the choice summer fruit, each of which earned him two cents. Meanwhile he began leafing through various mail order catalogues in the hope that someone was advertising telescopes for sale. His search came up with not one, but two sources. One firm was offering a 3 inch Bardou refractor for the princely sum of $65. His heart must have sank as he realised he would never be able to afford such an instrument, at least for the foreseeable future. But the other advert gave him good cause for optimism; this time it was a 2 inch refractor offered by a firm in St. Louis for $18. By the end of June 1916, Peltier had saved up that $18 and without a moment’s hesitation despatched his order, together with the payment.

The next nine days must have seemed like an eternity as the young squire anxiously watched for the postwagon to pull up on the dirt road leading up to the homestead. Every morning at 11am he’d be there to greet the postman, but on one faithful morning, he delivered that magical package. In prose that would melt even the hardest heart, Peltier described the ceremonial unboxing;

Plopping on the ground right beside the mailbox I hastily removed the outer wrapping of corrugated paper to find inside a round case of heavy cardboard. I pulled off the cover of this case, and there, wrapped in tissue paper, was my telescope; a beautiful thing of black pebbled leather and shining brass.

pp 53

The telescope was actually designed for terrestrial viewing. Technically, it was a four draw instrument, with an achromatic objective of 2 inch aperture and focal length of 3 feet (so f/18). An additional lens placed between the ocular and the objective provided an upright image but that hardly mattered to the young astronomer. He had a telescope, and it was his pride and his joy!

As the postwagon pulled away, he took his first look through the instrument but was somewhat dismayed to find that it yielded a blurred image. Peltier, you see, knew absolutely nothing about how a telescope works! How could he possibly know? He had to learn how to focus it by moving the outermost drawtube first towards the objective, and then away from the same, until the sharpest, clearest image was presented and that position, he quickly learned, depended on the distance to the object in view. At lunchtime, the family gathered round the newly arrived instrument, for it was truly a thing of wonder! They all had a gander though it, and all were smitten. What a marvellous contrivance a telescope is!

The author’s charming 3 draw spyglass, with a one inch objective.

 

 

The instrument, which he affectionately named, the Strawberry Spyglass, came supplied with two eyepieces, delivering powers of 35x and 60x, as well as a solar filter. Peltier quickly learned that in order to optimise its performance, it would have to be rigidly mounted. But the supremely frugal and resourceful Peltier soon solved this problem by hobbling together a disused fence post, an old, heavy millstone and some planks of wood. Let the reader understand; nothing at Brookhaven was discarded; nothing went to waste. The mount allowed the telescope to move smoothly both in azimuth and altitude and was apparently as solid as a proverbial rock.

Leslie Peltier looking through the Strawberry Spyglass.

The Strawberry Spyglass was to be his constant companion under the starry heaven for the next three and a half years. And what a journey it took him on!

He writes:

Despite its diminutive size a 2 inch telescope is fully capable of doing serious work. A quality scope of this aperture will reveal a representative example of every major class of celestial object that can be seen with the very largest instruments.

pp 58.

He marvelled at Jupiter’s constantly changing cloud belts and the bewitching cadence of its Galilean satellites as they lapped the gas giant. He beheld the glory of Saturn’s rings and could even make out the Cassini Division and also managed to track down the distant planets, Uranus and Neptune, with the 2 inch. He followed with singular joy the evolving phases of the Moon, watching how its craters and mountains changed their aspect as the angle of sunlight striking its surface advanced over time. This was all well and good but he wanted to see more, much more. Unfortunately, his by now heavily soiled and tattered copy of The Friendly Stars would not yield the information he desperately craved.

Sensing his frustration, Peltier’s mother presented him with a new book as a Christmas gift; A Field Book of the Stars, by William Tyler Olcott. A law graduate from the University of Connecticut, Olcott ditched it all to become an astronomical evangelist, writing popular astronomy texts for the growing number of people across the country who owned small telescopes. Needless to say, Peltier devoured its contents, conveniently arranged as they were into the 12 months of the astronomical year. It was with this book and the simple charts it contained, that Peltier enjoyed, as the seasons progressed, his virginal sightings of various bright nebulae, open clusters and a rich assortment of double stars. But what really caught his attention was a curious footnote written by Olcott:

Many readers of this book may be fortunate possessors of small telescopes. It may be that they have observed the heavens from time to time in a desultory way and have no notion that valuable and practical scientific research work can be accomplished with a small glass. If those who are willing to aid in the great work of astrophysical research will communicate with the author he will be pleased to outline a most practical and fascinating line of observational work which will enable them to share in the advance of our knowledge respecting the stars. It is work that involves no mathematics and its details are easily mastered.

pp 63

This was dynamite to the young star gazer! How on God’s Earth could he turn down the offer of becoming an “astrophysical researcher?” It had, afterall, a rather exalted ring to it. So he wrote off to Olcott, and to his great relief, the gentleman duly replied, explaining that he, together with seven other active telescopists, had formed the American Association of Variable Star Observers (AAVSO). Mr. Olcott further added that if Peltier was in possession of a 3 inch or larger telescope, he could join the new organisation!

A 3 inch! Peltier only had a two inch, of course, but after a spell he worked up the courage to apply anyway. Though he spins an interesting yarn on what happened next in his autobiography, this author strongly suspects that the young astronomer deliberately fudged the issue by making the number 2 look like a 3 on the form! Would you shoot him or salute him?

His application was accepted, and the rest, as they say, is history!

Peltier received his first charts from the AAVSO indicating the positions of the target variable stars he was to monitor. The procedure couldn’t be simpler. One would estimate the magnitude of the variable star marked on the charts using nearby stars of fixed magnitude, some brighter and some fainter than the variable under study. But Peltier found, not surprisingly, that this was easier said than done. He first had to find those star fields with a spyglass offering a small field. Using a copy of Upton’s Star Atlas (which served him well for 30 years before dying a tattered death), his maiden surveys were made during the cold nights of February 1918, where he attempted to track down R Leonis. But try as he may, he couldn’t find the correct field for several nights until fortune finally smiled on him on the evening of March 1 1918, when the Strawberry Spyglass first centred Omicron Leonis and moving “a little more than one field to the northeast,” he stumbled upon the little triangle of stars, one of which represented the Mira type variable he was after. Though this author has never looked through Peltier’s 2 inch telescope, it can be deduced that since the distance between Omicron and R Leonis is about 2.3 degrees, his telescope must have offered a true field of about 2 angular degrees; wide enough to monitor many variable stars. This was the first of legion magnitude estimates Peltier was to make and submit to the AAVSO over the decades to come.

By this time, Peltier had dropped out of High School, not because of any premeditated rebellion against his parents or society in general, but out of sheer necessity. Schooling in those days was often interrupted, owing to circumstances beyond his control. His country was at war and his older brother, Kenneth, had enlisted in the army, serving in war ravaged France. Thus, extra duties had to be assigned to him at Brookhaven. But Peltier’s three years of further education were looked back upon with great affection. And like most young people in those days before the relative comfort of the school bus, he had to peddle the 4 mile trip to and from his home in all weathers. Peltier explains in his autobiography how he was particularly captivated by the biology lessons. The school had two microscopes stored under large bell jars to keep the dust at bay, and he was taught the rudiments of cell biology and histology, cutting thin sections with the microtome and staining them with all manner of dyes. He was particularly captivated by the hay infusion; made by adding a handful of hay to a jar of rainwater and letting it stand on a window sill for a few days before a thin veneer of scum would appear on it surface. And though Leslie didn’t have a microscope of his own, he would improvise by using his 60x ocular as a high power magnifying loupe. Placing a drop of this artificial ‘pondwater’ on a pane of glass, he’d run his makeshift microscope across it and was able to make out the skirting antics of myriad ‘animalcules’, charming Paramecia and Colpidia, which, in fact, are just large enough to make out with the naked eye (a personal reminisce from my own childhood) under suitably strong illumination. He writes:

I tried to envision in my mind what an infinite galaxy of worlds our haymow held in bonds of arid dormancy. Surely they must outnumber the countless stars of the sky. I wondered too, how many spyglass lenses had ever watched two such extremes; the microcosmic worlds in water drops and the giant orbs of the Milky Way.

pp 81/2

What an invalubale lesson to learn in life! To gain a true sense of perspective of the very small and the very large, and all from the application of his Strawberry Spyglass!

June 8 1918 was forever etched into the memory of Leslie Peltier, for in the afternoon of that faithful day there was to be a solar eclipse visible across large swathes of the American nation. From Brookhaven it would cover some three quarters of the Sun’s disk. And as luck would have it, the auguries of nature forecast good seeing conditions from the get go. Dawn broke with heavy dew soaking the fields, and the sky presented as cobalt blue, decorated here and there with delicate, fleece white clouds which only added to its comeliness. And, as morning gave way to afternoon, clear skies prevailed.

Peltier moved his makeshift mount to allow him to obtain the best views of the Sun through his 2 inch telescope as it began to sink ever so slowly into the southwestern sky.  And though it was a small instrument, it was a far cry from the apparatus he used to view the only other eclipse he had solemnly witnessed as a young boy.  While at school, some ten years before, his teacher instructed the pupils to flame pieces of window glass so that they would become glazed in a thin layer of soot, allowing the children to safely observe the apparition. This time round however, Peltier resorted to what many other telescopists of the era did; use a thick piece of welder’s glass, which imparted a strong red tint to the solar image.

As the time of first contact approached, he would entertain himself by observing the many sunspots that peppered the disk of our star, and there were many to see on that day, as it was around the time of solar maximum. The eclipse began right on time, and he eagerly drank up the views through his telescope. His keen eye picked up the jagged edges of the Moon silhouetted against the blinding solar furnace, but he was also mindful to observe the surrounding landscape during mid eclipse. He writes:

At mid eclipse I turned away and looked about. Everything I saw, the nearby fields, the distant vistas, all seemed wrapped in some unearthly early twilight. The sky seemed darker; shadows faint and indistinct. A cool wind, almost chilly, had sprung up from the west. The grass beneath the nearby maple now was appliqued with scores of crescent suns, projected there from each small aperture between the leaves above.

pp 93

But an even greater spectacle awaited Peltier as the suns rays fell beneath the horizon later that evening. Thankfully, the skies remained resolutely clear as he set up his Strawberry Spyglass for a night of variable star observing. But as he was clamping his telescope to its mount in the yard, his eyes gazed up to heaven and immediately were met by an intensely bright star that he had never seen before! Located near the bright summer luminary Altair, it was just as brilliant in his estimation. Was this a renegade planet that had strayed far from the ecliptic? Surely not! And Upton’s Star Atlas left him none the wiser. Leslie Peltier had just seen his first nova, a star that had flared up suddenly, increasing its brilliance by a million times or more! Fortunately, he could not claim it as his own, as that honour was bestowed upon the Bangladeshi–Indian amateur, Radha Gobinda Chandra (1878–1975), who had spotted it the evening before with his trusty 3 inch refractor.

It was a mesmerizing sight to Peltier though, and he watched in complete amazement as the star continued to brighten as the night progressed, reaching its peak luminosity on June 9, where the Ohio amateur logged a value of –1.4 in his journals, so about as brilliant as Sirius shines in the winter sky. The official reports published in the days and weeks after Nova Aquila 1918 made its appearance stated that it peaked at –1.5! Peltier continued to monitor the nova as it faded slowly through his telescope for years after that memorable June evening of 1918. Only after 11 years had the star fallen back to its original 12th magnitude.

As the weeks gave way to months and years, Peltier’s stamina for variable star work increased apace. By September 1919, he had amassed hundreds of valuable observations, all of which were published by the AAVSO. But after several years of dedication to his ‘astrophysical researchers,’ it became abundantly clear to his fellow AAVSO peers that here they had a man of extraordinary diligence and talent. But to break new ground he would need a larger telescope and accordingly the organisation offered him the loan of a much more powerful glass; a 4 inch f/15 Mogey refractor with its own equatorially mounted head. The only provisos were that he would employ it as diligently as he had used his own telescope and that he would keep the instrument in good working condition.  Peltier, of course, was only too happy to accommodate the new instrument and so his Strawberry Spyglass was duly retired from active service. It would however continue to occupy a special place in his heart for the remainder of his life.

The author’s previously owned and used 4 inch f/15 achromatic refractor, similar to the 4 inch Mogey presented to Peltier in the autumn of 1919.

 

 

 

 

 

 

 

 

 

 

 

 

Just how diligent was Peltier in the scheme of things? The reader of his masterful autobiography will be presented with a clue;

The slowly declining nova and my constantly growing observing list of variable stars kept the 2 inch busily occupied for many months. During the fiscal year of the AAVSO which ended in September 1919 it had watched the stars on a total of 190 nights; more than half the nights of the year.

pp 109

Intriguingly, this claim comports very well with the findings of another equally diligent amateur astronomer living half a world away; William F. Denning (1848-1931), who, like Peltier, lived out almost all his entire life in one place (in this case Bristol, England). This frequency is also supported by the records of the Devon based amateur astronomer Charles Grover. As stated before, this author, for a variety of reasons, has come to trust the records of historical figures more than his own contemporaries. Furthermore, in previously published work (data not shown) this author confirmed that observing opportunities indeed arise far more frequently than is commonly reported by ‘forum culture’.

Anyone who has ever had the opportunity to use a good 4 inch f/15 achromat will tell you that, provided they are appropriately mounted, they are a joy to use! Images are very crisp and sharp at both low and high power, and contrast is excellent. Rest assured, in comparison to his beloved 2 inch telescope, the Mogey would take Peltier’s observations to a whole new level of performance! But to make proper use of it, he had to mount it first. And like with his Strawberry Spyglass before, Peltier set to work building his own.

Unlike the mount for his smaller telescope though, the new arrangement for the larger Mogey would not be transportable. So, he had to carefully plan and select a location in which to permanently situate it. After some deliberation, he decided that it would have to go in the middle of the farm’s cow pasture, which, barring the exception of his grandfather’s maple trees which occluded the lowest 20 degrees of sky to the east, afforded excellent views from horizon to the zenith in all cardinal directions.

One might legitimately ask why a refractor was given to Peltier, when a reflector could do this work equally well. This author suggests that it was the former’s robustness and lack of maintenance which made them ideally suited to these tasks, especially working in all weathers. For example, mirrors needed to be recoated from time to time to enable them to perform at their best. They also required careful collimation. No such provision was needed with refractors though, the object glasses of which were hard to miscollimate and could last for decades and even centuries in comparison. In addition, the revolution wrought by the silver on glass reflector, which had swept the length and breadth of Britain and Europe more broadly, had not yet penetrated so deeply into the American amateur psyche.

Having spent the previous few years using an altazimuth mount with his 2 inch instrument, which entailed moving the ‘scope horizontally as well as vertically,  the equatorial setup, in comparison, would take some getting used to. But he clearly understood its considerable advantages in making his work that little bit easier to carry out. If its rotation axis were accurately pointed at the north celestial pole, it would enable him to accurately track his variable star targets using a single motion. Accordingly, he built a solid pillar on some level ground, then mounted the 4 inch, together with its equatorial head on top. Next, he spent a few clear nights accurately aligning the axis of rotation of the mount with the pole star, which hung 41 degrees above his northern horizon (the latitude of Brookhaven). It took a bit of getting used to, but with enough tinkering he managed to get it working well. Now he was ready for his first light through the 4 inch glass.

Beginning sometime in December 1919, the first part of his maiden voyage with the 4 inch was entirely devoted to sight seeing. In reverence to his 2 inch which was first turned on Vega, so too did he open his observations on this first magnitude star, which by now, had sunk low into the northwestern sky. He writes:

Three years before, on a warm summer evening, she had been the first star for my 2 inch spyglass. In the 4 inch she was almost dazzling, and, after critical focusing, beautifully sharp and clear.

pp 111.

Off he sped to SS Cygni, the irregular variable, which the Mogey could easily show him at magnitude 11.9. Then he took some recreation, paying a visit to his favourite seasonal showpieces. He marvelled at the Ring Nebula, explored the cavernous reaches of the Great Nebula in Orion, with the fetching Trapezium at its epicentre. The Pleaides was a blizzard of stars and, moving into Cygnus, he admired the gorgeous colour contrasts of Albireo. Casting his gaze a little to the southeast, he would have noticed that Chi Cygni, the famous long period variable, was invisible on this occasion. But his knowledge of the sky quickly allowed him to track it down. And there it was, hanging at the precipice of visibility, laid low at magnitude 13! This was a mighty instrument! With it he could gather four times more light and see things twice as finely as his Strawberry Spyglass. In one fell swoop, a whole new sky was opened to him!

Peltier wasted no time using the Mogey, logging in a greater tally of variable stars than ever before and submitting his results to the AAVSO every month. But the open air observatory he had built in the cow pasture was not without its problems. For one thing, he had no choice but to end his observations when the object glass dewed up (for some reason dew caps were not a standard item on early 20th century refractors), requiring him to make not too infrequent retreats indoors to remove the condensation, or on the coldest nights, the hoar frost that invaded the smooth surface of the glass. Still, he was always grateful for the warmth provided by the fire, especially on the most frigid spells. More seriously though, the curious bovines inhabiting the pasture would often use the pillar as a scratching post and this might potentially destabilise structure. A partial solution was arrived at by building a fence around the pillar, which kept the livestock at bay. By the autumn of 1921 though, his father, acknowledging the dedication his son had for his astronomical work, suggested that they build a proper observatory for the Mogey, complete with a rotating dome! This was music to Leslie’s ears and immediately they set to work drawing up plans.

His father, of course, was an accomplished carpenter and builder. After all, he constructed the two story house at Brookhaven where all the Peltier family grew up. They would lay a concrete foundation and erect a rectangular wooden building 14 feet long and 10 feet wide. On top of this they would fit a fully rotatable dome with a diameter of 9 feet. Everyone in the family helped out, as well as Leslie’s school buddy, Gilbert Miller. Erecting the walls presented little problem, but getting the dome to work satisfactorily was somewhat more of a challenge, but eventually they worked out the mechanical bugs by trial and improvement. It goes without saying that Leslie was immensely proud of his new astronomical observatory. The 4 inch Mogey was the centre piece, of course, but now had a desk and chair in situ to record his observations. The dew and frost would also be less of a problem. He did however, admit to missing the sounds of nature that saturated the air around his erstwhile outpost in the open pasture, as well as being able to see the full canopy of the sky and the excitement of witnessing a wild meteor blazing across the sky.

Though he grew fond of the Mogey, it didn’t remain long in his hands. Grateful for all the high quality work he was contributing to the AAVSO, the Director of Princeton Observatory, Henry Norris Russell, wrote Peltier offering him the loan of a 6 inch refractor. Gathering more than twice as much light as the 4 inch, this instrument would allow Peltier to follow his variable stars longer into their cycles, many right down to their minimum. Naturally enough he accepted the instrument but was not entirely prepared for what it would look like. Expecting it to have a tube of the order of 8 feet, he worried that his newly designed observatory might not be able to accommodate the larger telescope. But his fears were allayed when the boxes containing the instrument and its mount arrived from Princeton. Instead of an 8 foot monster, the telescope he received was one of rare pedigree; a 6 inch refractor with a focal length of just 48 inches (4 feet)!

Belisarius; the author’s previously owned 6″ f/8 Synta achromat.

 

 

 

His sense of relief was palpable:

The first box I opened cleared up the mystery and raised my drooping spirits to an all time high for when I removed the strapping and lifted the lid, there before me, a rhapsody in dark mahogany and gleaming brass, lay my new telescope, just four feet long; one foot shorter than the 4 inch. I would not require a head shrinker’s services after all.

pp 125

The exceptionally high quality Istar Persus 6″ f/8 achromat tested in the field by the author.

 

 

 

 

 

 

 

 

 

 

After unpacking and assembling the instrument together with its equatorial head, he had to remove the Mogey from the centre of his Universe and have it shipped back to Cambridge from whence it came. After setting it up and taking the instrument for a spin, he came to appreciate the strengths and weaknesses of the instrument. Vistas like the Double Cluster in Perseus, the star fields around Deneb and Gamma Cygni, as well as those further south in Scutum and Sagittarius were breathtaking through the instrument. It was he insisted, designed for low power sweeping and offered a very generous two degree field. He explains his reasoning thus:

The instrument’s shortcomings were few and of little consequence since, for my observing, I needed no high magnification. For observing the planets, for separating double stars, or any work which requires high powers and critically sharp images, the focal ratio of an objective should be at least f:15, meaning that roughly the length of the scope should be 15 times the diameter. That of my new scope was only f:8.

pp 126

Peltier makes an interesting assertion here. That said, this author, having extensive experience resolving double stars with two different 6” f/8 achromats from the modern era found that their ability to split binary systems was not appreciably affected by their moderate relative apertures. Indeed, both instruments proved to be excellent in this regard. For example, the higher quality Istar unit tested here a few years back even managed to split the sub arc second pair, Lambda Cygni, under excellent seeing conditions, without much difficulty! So, I think Peltier was flatly wrong about double stars for this specification of instrument and there is no evidence from his autobiography that suggests he tested this claim to any appreciable extent. One feels Peltier fell into the trap of following ‘tradition’ rather than testing ‘received wisdom’ thoroughly before arriving at a conclusion.

Of course, a relatively fast doublet like this, derived as it was from the early workshops of the late 19th century, would probably have not operated as well as could be and thus may go some way to explaining his statement. Modern 6 inch f/8 achromatic doublets are, almost certainly, superior to Peltier’s instrument at high power work. I would however agree with the great astronomer in regard to the instrument’s planetary performance. These days, there are much better instruments to be had for less pecuniary outlays than the typical cost of these refractor units; an 8 inch f/6 reflector, for example.

iStar’s 8″ f/5.9 achromatic doublet; very good for low power sweeps. Useless for everything else.

 

 

 

 

 

 

 

 

 

 

Peltier did some research on the pedigree of the 6 inch f/8 telescope in his possession, finding that it was probably of late 19th century design, and originally made as a comet sweeper. Indeed, Zaccheus Daniel, a former student of Princeton University, used the instrument to discover a comet in 1907 and two more in 1909 (1909A and 1909E). Feeling that its distinguished history was all but forgotten, Peltier did something extraordinary:

Rather piqued by such neglect, I vowed that some recording of its earlier deeds, as they were known to me, would now be permanently preserved. I whetted up my pocket knife and on the midriff of that wooden tube I deeply carved the name of Daniel and beneath it cut the date of his three comet catches.

pp 127.

This author was rather taken aback by this gesture. Yes, while there is no doubt Peltier meant well, it was also on loan (see page 124) from Princeton University. So, strictly speaking, it was not within his remit to sanction this act.

But I digress!

It was about this time that Peltier decided to add another string to his bow. As well as using the 6 inch to monitor his variable stars, he would begin the hunt to find comets of his own. The 6 inch telescope was thereafter referred to as the Comet Catcher! But in order to do such work, which involves simple horizontal sweeps of the sky, it would be a great advantage to mount it in altazimuth mode. By now his old school friend, Gilbert Miller, had secured a good job as a draftsman in a local company, and he was able to modify the existing equatorial mount that accompanied the instrument in such a way as to enable it to be used either equatorially (which benefitted his variable star work) or altazimuthly, to optimise his comet sweeps. Problem solved!

It was on Friday November 13 1925 that Peltier struck it rich! Darkness fell early upon the landscape, as it always does at this latitude in November, and it was business as usual for the young astronomer. Off he went to the dome, now having completed five full years of active service, opened the shutters and readied the telescope for what he thought would be a routine night of variable star monitoring complemented by a comet sweep. After visiting R and T Coronae, old familiars of late autumn, he swung the telescope into Bootes, now sinking low in the northwestern sky. Sweeping through the extreme northern edge of the constellation, his 6 inch eye picked up a ghostly blur and moving his gaze downwards Peltier could just make out the faintest traces of a tail. This was a comet alright, and it was barely twenty minutes into his observing schedule! But instead of jumping about like a jackass, he took heir of himself by first making an estimate of its magnitude. Defocusing on a faint field star until its size roughly matched that of the comet, he accurately recorded its brilliance to be of the 9th magnitude. Next, he made a sketch of the object in the field of view using several stars as an aid to identifying its precise location on his atlas. Finally, he returned to the telescope and noted its relatively rapid motion among the fixed stars. It was sprinting south!

Next, he had to communicate the sighting to the hub of all astronomical knowledge; Harvard College Observatory. Preparing his telegram, he wrote: NINTH MAGNITUDE COMET ONE FIVE TWO FIVE NORTH FORTY FOUR DEGREES RAPID MOTION SOUTH. Now that electricity and a telephone line had finally come to Brookhaven, he tried to get through to the telegram office but it had closed for the evening. After getting through to the local operator he was informed that all emergency telegrams could be sent through the signal tower at the Pennsylvania Railway depot but unfortunately there was no way he could be connected directly. Naturally frustrated, he tried to track down his parents, but they had popped out in the car. This telegram just couldn’t wait, so he resolved to get on his bike and peddle his way in the dark to the railway depot several miles distant. Finally, he got there, climbed the steps to the high tower and waited patiently for the operator to tend to his request. At last, the telegram was despatched. There was nothing to do now save to make his way home and begin the long waiting game.

In a cruel twist of fate, the next several days were completely clouded out and thus he hadn’t a ghost of a chance of following the comet’s course into southern skies. All sorts of doubts started to beset him. Was this really a new comet or had someone seen and reported it before him? Did the telegram even get through? Eventually though, an agonising 8 days later, a phone call came through for him from a one Mr. Wahmhoff, the local pharmacist.  Wahmhoff sounded out the telegram he had received from Harvard; Mr. L.C. Peltier of Delphos, Ohio, had indeed discovered a comet and his name would forever be associated with it!

He made his way to the observatory housing the 6 inch, the instrument which had shown him the icy interloper before no other human being had laid eyes on it. And whetting his pen knife, he began to carefully carve its name into the tube: Peltier 1925K.

This was but the first of a total of a dozen comets discovered by his diligent vigils under the stars. The discovery of 1925K brought considerable notoriety to Peltier and he was personally congratulated by many of his astronomical peers; both amateur and professional alike. He also began to receive visitors to Brookhaven; mostly enthusiastic school kids and fellow AAVSO members, but yet remained suspicious of the press, which he felt were exploiting his new–found fame for their own swinish gains.

By his late twenties though, other things began to preoccupy the Ohio stargazer, not least of which was a pretty young brunette, Dorothy(a.k.a. ‘Dottie’) Nihiser, who grew up in the nearby town of Delphos. Dottie attended the same High School and Sunday school as Leslie, but being ten years his younger, their paths naturally never crossed that often whilst growing up. All that changed in 1925 however, when Leslie took up temporary employment as a stock clerk in a motor truck factory, which necessitated him driving into town every day.  And it wasn’t long before the pair became reacquainted with each other. Dottie was then in High School but was an excellent student who went on to study at Ohio’s Wesleyan’s University. They began dating in 1928 and were married on  November 25 1933.

Like Leslie, Dottie was a keen amateur naturalist and, in what can only be described as a beautiful honeymoon (described at length in Peltier’s autobiography), the happy couple took off on a journey of exploration to the American Southwest in their beat up 1929 Ford Sedan, camping here and there along the way. The next nine months were to be the happiest in Peltier’s life, visiting the wilds of Texas, with its rugged mountains, canyons, great rivers and desert trails.

Peltier was deeply impressed with the great natural beauty of this American wilderness, which he revered as a kind of ‘geological Mecca’ of the young nation. Back then, the skies here were utterly pristine and, as he later admitted, were in a completely different league to those he enjoyed back in rural Ohio. It was on this trip that he first caught site of the brilliant star Canopus, the brightest luminary of the far southerly constellation of Carina. Small wonder, he noted, why so many first-rate astronomical observatories were springing up all over the region.

This extended honeymoon to the Southwest was possibly inspired by a trip the courting couple took to Mount Locke in Western Texas a few years earlier, during February of 1931, where they hooked up with the Belgian–born astronomer, Dr. Van Biesbroeck (Van B.), who was, at that time, a staff astronomer at Yerkes Observatory, overlooking Williams Bay, Wisconsin. Accompanying them on the trip was the Comet Catcher, the mahogany tube of which was now replaced by a much lighter tube fashioned from rolled metal. Indeed, this new tube served him well for the remainder of his life.

At the summit of Mt. Locke, 7000 feet above the surrounding plains, the telescope provided some charming deep sky views of the southern sky, but Peltier always wondered whether Dr. Van B. would truly appreciate them, given his familiarity with much larger instruments. Here, a full 1.3 miles above sea level, he noticed how the stars hardly twinkled at all owing to the more rarefied air at high altitude. But it wasn’t so much the stars that captivated the couple on Mt. Locke that evening, so much as the deafening silence permeating the place. He writes:

The impression that I will longest remember of the night on Mt. Locke had nothing to do with sharp stellar images or the new stars I saw in the south. It was, instead, the feeling I had, while all alone in the darkness, of complete and utter detachment from all the rest of the world. There was absolutely no sound. Earlier that evening Van B. had called this to our attention by asking us to remain perfectly still for a moment and “listen to the silence.” We listened in vain for there was nothing up there to make a sound. It was winter and there was no nocturnal bird or insect sounds. There was no hum of wires, no rustle of leaves, no sigh of wind. The mountaintop was a silent wonder.

pp 168/9

A view of McDonald Observatory from highway TX-118. Mt. Fowlkes is on the left while Mt. Locke is on the right. The dome of the Hobby–Eberly Telescope is visible on Mt. Fowlkes while the domes of the Harlan J. Smith Telescope and Otto Struve Telescope are visible on Mt. Locke. Image credit: Wiki Commons.

For the next three years, the couple took up home on the Peltier estate, in Leslie’s grandfather’s cabin, situated on the opposite side of the cow pasture and so about equidistant from the domed observatory. The accommodation proved adequately roomy and comfortable while it lasted.  And it was here that their son, Stanley, was born. But their circumstances changed when Leslie’s paternal uncle, who was the original occupier of  grandfather’s house, returned to Brookhaven together with his aunt. The young family had no choice but to seek new lodgings. What’s more, his job at the truck factory folded but he soon found another one, this time, as a designer in the Delphos Bending Company.

It wasn’t long before they successfully rented a home in town, conveniently near his new employment. But since there was no easy access to his telescope, he had to totally rethink his way forward. His solution was as ingenious as it was simple; enter Peltier’s now famous Merry Go Round Observatory, the inspiration for which came to him whilst idly swivelling in an office chair at his work. In essence, it was a one roomed structure, with the objective end protruding into the outside air, and the ocular end positioned inside. He would sit in a renovated leather upholstered car seat, the height of which could be adjusted, and the entire structure could be rotated through 360 degrees simply by turning a wheel. Another wheel allowed smooth movements in altitude. Needless to say the structure worked like a dream, allowing him to bag several more comets as well as making thousands of additional variable star measures.  Expressing his pride in the design of the Merry Go Round Observatory Peltier wrote:

When in 1948 the giant 200 inch telescope on Mt. Palomar finally swung into action the press made much of the story that, when used at its prime focus, the observer, for the first time in history, would ride with the telescope. I gloated just a little over this, for by then I had been riding with my telescope for eleven years, and furthermore, I had not blocked out a single ray of light while doing it.

pp 178/9.

By now, Peltier was unquestionably one of the most dedicated star gazers in history, with a correspondingly encyclopedic knowledge of the night sky, so it was inevitable that he would discover more things in heaven than a dozen icy comets. Indeed, his name is also forever associated with five guest stars that made their explosive appearance in the skies over Ohio, just like the one he witnessed with his Strawberry Spyglass on that faithful night of June 8 1918. The reader can learn of these discoveries in Chapter 23 of Starlight Nights, but what piqued this author’s attention was his discussion of other types of visitors; what we have come to call ‘UFOs’ and ‘little green men’.

Intriguingly, Peltier declares that despite spending more time under the stars than arguably anyone else on Earth, he never once saw such objects. Indeed, he called the 1950s a period of ‘mass psychosis’. He remembers receiving numerous phone calls over the years from folk who saw strange things in the sky. In a humorous exchange, Peltier does however recount a curious incident during which, for a brief few moments, he himself was duped, only to later discover that his ‘flying saucers’ were nothing more than a flock of Canada Geese flying southward for the winter! In the end though, he maintained a healthy scepticism concerning whether such beings could really exist, despite the vastness of the Universe that he explored each clear night with his telescope. He was, afterall, too much of a Christian to go ‘a whoring after other gods’, as the Biblical narrative phrases it.

The 1940s brought its fair share of changes for the Peltiers. They were busier than ever. Leslie still had his full time job. Their second son, Gordon, arrived on the scene, while Stanley enrolled in the town’s kindergarten. Both Dottie and Leslie became actively involved in the local church, with its garden fetes and the training of a new generation of cub scouts. There was also an uprooting. The owners of the premises they rented in town notified the family that they intended to move back in, which meant that they had to search for a brand new home once again. After looking at one or two properties, they settled on a twelve acre estate, called the Old Moenning Place, which they bought outright. A fine, large house, already over a century old, it had seven large rooms with grand, high ceilings. More than 40 species of tree inhabited the various parts of the land that attended the homestead and it was conveniently located on the western edge of town, which meant that not much of the smog and dust from the various industries would accumulate on the premises or in the skies above, owing to the prevailing westerly winds that blew across the grounds. Though it was quite a task, involving several years of regular work during each spring and summer, the family slowly transformed the grounds into a picturesque natural haven of ‘cultivated wildness’ and it was appropriately renamed New Brookhaven.

Peltier selected a spot, some 100 yards north of the house, where his Merry Go Round Observatory was rehoused. And though there was minimal light pollution here owing to some distant lamp posts, the trees were quite effective at blocking it ought. Indeed, so confident was he that this would be his final abode, Peltier had a new, solid concrete foundation laid to support the observatory. But in the middle of the summer of 1959, Peltier got yet another offer, this time, of a truly gigantic telescope; a 12 inch Clark refractor to be precise, complete with its own observatory, transit room and, as Peltier himself put it, “all the trimmings!”

The instrument and its massive equatorial mount was originally constructed back in 1868 by Alvan Clark & Sons and used by Professor J.M. Van Vleck at Wesleyan University, Middletown, Connecticut, but was later purchased by Miami University, Oxford, Ohio in 1922. But over the years, the observatory in which it was housed fell into disuse as more and more buildings were erected when the campus expanded. By the time Peltier was contacted by the University, it was completely boxed in! When he made a visit to the observatory, Peltier found the telescope objective was completely covered in dust, with a small chip at the egde which was partially covered by the retaining ring. “Old telescopes never die,” he wrote, “they are just laid away. There is little about a telescope that can deteriorate and the lens, the vital organ, even though a century old, can still have all the fire and sparkle of its youth.” pp 232

Because of Peltier’s great acts of philanthropy for the community of Delphos, he was held in very high esteem, and he was fortunate enough to have a boss who was capable of orchestrating such an enormous task of transporting the giant telescope, its imposing dome and octagonal walls from Miami back Delphos, a distance of 125 miles. Peltier had selected a site on his own premises for the new observatory, somewhat further north of his Merry Go Round. The dome, which was 22 feet in diameter and 11 feet high, had to be sawn in two.  The eight sided walls holding it up also had to be dismantled and the components moved individually. Needless to say, it was a massive engineering undertaking but he had an army of loyal friends, who were only too willing to lend a hand in its reconstruction. His two grown sons also put their back into the project and Dottie provided refreshments for all. His fellow AAVSO members, Don and Carolyn Hurless, based in Lima, Ohio, elected to do the painting and decorating of the inside of the new observatory. And, as stated previously, since the Peltier’s never wasted anything, some of the materials from the original dome he had built all those years ago with his father, were also incorporated into the new structure.

Before mounting the telescope, Peltier did some makeshift star testing on it but found the images to be unsatisfactory, only to subsequently discover that one of the elements had been fitted the wrong way round at some time in the past. But with a bit of help from his academic contacts, he was able to rectify this problem quickly. The 12 inch doublet achromat had a focal length of 15 feet 7 inches (relative aperture 15.6) and Peltier himself was delighted with the images it rendered as he took it on a grand tour of the heavens. He writes;

Since finally settling into its new home the 12 inch has done its level best to show off its accomplishments and as yet I have not ceased to marvel at the wonders it reveals. Star clusters such as M 13 in Hercules and M11 in Scutum are gorgeous quite beyond description, and these are only two among a host of these far away star cities whose sparkling street lights seem to wind and twist about until they fade out in the distance. A favourite of mine is known as NGC 4565, the edge on spiral galaxy in Coma Berenices. Still another is the weird and ghostly Ring Nebula in Lyra with its faint and difficult hot blue star in the center of the ring. M42 the Great Nebula in Orion, is breath taking in its sharply defined bright and dark nebular cloud forms. All of these celestial showoffs I had seen hundreds of times before in my other telescopes, but with the 12 inch, everything that before had been vague and elusive was now sharp and clear. It was pleasant to make their acquaintance all over again.

pp 221.

This was the last telescope Peltier would use regularly in his nightly vigils and it served its purposes very well. Where the Comet Catcher barely reached magnitude 14 on the best nights, the 12 inch took over, registering stars fully two magnitudes fainter. Its prowess was amply borne out when he, Don and Carolyn followed the slow fading of a supernova in one of the faint spiral galaxies inhabiting the Virgo cluster, which remained completely invisible in the 6 inch. Indeed, for the remainder of his career, the time divested on each instrument was 50:50. Indeed they perfectly complemented each other!

In the autumn of his life, Peltier, like so many lovers of the night sky, lamented the march of ‘progress’, especially in regard to the growing problem of light pollution. He concludes:

The moon and the stars no longer come to the farm. The farmer has exchanged his birthright in them for the wattage of an all night sun. His children will never know the blessed dark of night.

pp 224

Crowned by Dr. Harlow Shapley as “the world’s greatest non professional astronomer,” over a span of six decades, Peltier contributed an incredible 132,000 variable star observers to the AAVSO. Actually, from the time he joined the AAVSO aged 18, he never once missed sending in his monthly report This he could add to his tally of a dozen comets and 6 nova ( four with his naked eye!) finds. Asteroid 3850 was also named in his honour. In 1947, Peltier received an honorary doctorate from Bowling Green State University. In 1965, a Californian mountain, the site of Ford Observatory, was named Mt. Peltier to commemorate his achievements, and in 1975 he finally received his honorary high school diploma from Delphos Jefferson High School. Peltier died of a heart attack on May 10 1980, aged 80 years. Those who knew him unanimously declared that the man described in Starlight Nights was one and the same as the real Leslie Peltier. Having absorbed this engaging work of prose, this author sees no grounds to disbelieve it!

Recommended reading for all astronomers and those who lament the bucolic days before city sprawl and light pollution.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Appendix:

                                                              Comets Discovered by Leslie Peltier

Comet                Date of Discovery

1925d                      13.11.1925

1930a                      20.02.1930

1932K                      08.08.1932

1933a                      16.02.1933

1936a                      15.05. 1936

1937c                       27.02.1937

1939a                       19.01.1939

1943b                       19.09. 1943

1944a                       17.12 1944

1945f                         24.11.1945

1952d                        20.06.1952

1954d                        29.06. 1954

 

Some other sources of interest

https://www.aavso.org/leslie-c-peltier

http://articles.adsabs.harvard.edu//full/1980JAVSO…9…32H/0000032.000.html

 

Dr. Neil English is author of many books on amateur and professional telescopes and has been a regular contributor to Britain’s Astronomy Now magazine for over 20 years. He is currently completing an ambitious historical work; Tales from the Golden Age of Astronomy, chronicling the lives of visual observers over four centuries since the invention of the telescope, which is to be published in the spring of 2018.

 

De Fideli.

Tales from the Golden Age: Clyde W. Tombaugh; Discoverer of Pluto.

Clyde W. Tombaugh pictured here with his homemade long focus 9 inch Newtonian reflector.

 

Preamble 1

Preamble 2

Can it be a coincidence that many of the most pre-eminent amateur astronomers to emerge in the United States during the early 20th century were born into rural communities? We have already seen some of the work of the late Sky & Telescope columnist, Walter Scott Houston, who was born and raised in Tippecanoe, Wisconsin. Then there is Leslie Peltier, the great comet and variable star observer, who lived his entire life among the strawberry fields of Delphos, Ohio. And that list wouldn’t be complete without Clyde W. Tombaugh, who hailed from a farmstead seven miles from the town of Streator, Northern Illinois. In this vast open country, where fields would stretch from horizon to horizon, the glory of the night sky would have been made manifest to their young, curious eyes, stoking an early passion for all things astronomical.

No; there are no coincidences, only convergences.

These great American amateurs all started out with humble beginnings. Life was hard, very hard by modern standards, but ultimately rewarding. It was into this kind of world that Clyde W. Tombaugh was ultimately thrust. The first born and eldest son of Muron (born 1880) and Adella Tombaugh, Clyde entered the world on February 4 1906. For a few generations, the Tombaughs were distinguished from many other families in their rural community in being an educated bunch. Clyde’s grandfather was University educated and served as a school teacher. His father too had high ambitions to follow a career in mechanical engineering but the circumstances of his early days meant that there were many stops and starts in his education, with the result that, although he attended the local University of Illinois, he never completed his degree. More children arrived in rapid succession to Clyde; first Esther, two and half years his younger, and then Roy, Charles, Robert and finally Anita. Such a large family demanded an industrious bread winner and Muron did his Sunday best for his family, running a busy rented farm which eked a modest income from the cultivation of oats, wheat and corn. He also singlehandedly managed a threshing company which catered for the local farming community.

Being the eldest in the family, Clyde quickly became like a second father figure to his younger siblings and helped look after them when his parents were preoccupied with other matters. By all accounts Clyde’s elementary school days were happy and productive and he was lucky enough to have teachers who encouraged the boy’s natural curiosity. He excelled at history and geography. But his transition to high school was marred by a particularly vicious bout of whooping cough, which left young Clyde bedridden for a few months, and as a result he fell behind with his studies. After school, he was expected to help out on the farm, planting seed beds, cultivating, harvesting and threshing crops as they matured in their appointed time. In those days before mechanisation, work days on the farm could be were very long, often lasting from seven in the morning until 6 in the evening. In these ways, Clyde’s early life was no different to many thousands of other youths, especially since many late teenagers had enlisted in the U.S. army between 1917 and 1920.

In high school, Tombaugh enjoyed the elementary courses in physical science and biology and in his spare time he’d often be found reading into the night, with only a kerosene lamp for light. He reputedly read and studied the Bible from cover to cover; quite a feat for such a young man and which had a lasting effect on him, right on into old age. He also borrowed his father’s old books on engineering mathematics and even dabbled in some ancient Greek and Latin. Clyde’s interest in astronomy was piqued by his paternal uncle, Lee, who’s family lived and worked on a nearby farm and who cultivated a life long interest in astronomy. Lee was the proud owner of a 3 inch singlet (read non achromatic) refractor giving a fixed power of 36 diameters. While the optics on such a telescope were understandably so-so, they did give good views of the lunar regolith, which mesmerised young Clyde.

Responding to Clyde’s growing interest in astronomy, Muron and Lee chipped in to purchase a new and in many ways, more serious telescope; a 2.3 inch aperture long focus achromatic refractor offered by Sears Roebuck & Co. (an early U.S. based department store), which was equipped with a single ocular delivering a power of 45x. That telescope enjoyed a very long and productive life. In those early days, the Sears family telescope alternated between his home and his uncle Lee’s. It was with this telescope that Clyde enjoyed his first decent view of Mars during a favourable opposition, where it showed a few dark markings and the polar ice cap. By now, Tombaugh had been enthralled by some pamphlets circulated by the Tennessee amateur, Latimer J. Wilson, who owned a magnificent 11 inch reflecting telescope with which he began to draw the canals of Mars, sensationalised by the late Professor Percival Lowell and the Italian astronomer, G.V. Schiaparelli.

In 1922, the first upheaval in Clyde’s life occurred when the family crops failed. Seriously strapped for cash, the Tombaughs were forced to move to Burdett, Kansas, where Clyde’s uncle Lee had recently moved to manage a 250-acre property. He found the move especially stressful though, as he had forged a very strong bond with his first cousins who lived in Streator. Then in 1924, Clyde suffered a particularly nasty fall while pole vaulting which all but ended his keenness for athletics and football. After graduating from Burdett High School in 1925, he considered enrolling at the local University of Kansas but had to save the money to pay for his University fees. Apart from his work helping out on the farm, Clyde’s desire to make a serious sized telescope grew ever more strong, and with the help of some books and magazine articles, he ordered up the materials to make a long focal length 8 inch reflecting telescope from scratch. Completed in April 1926, it had a focal length of 84 inches, which he had intended to mount inside a long wooden tube and mounting with two setting circles (also of wood) to assist in pointing the instrument. All that was left to do was to get the mirror blank silvered. Since he did not have the chemicals at hand to do the silvering, he entrusted the mirror to a telescope maker, a one Napoleon Carreau, who had set up a business in Wichita about 140 miles away.

Mr. Carreau did the lad a favour and had the mirror tested prior to silvering. And what he found didn’t exactly inspire; the mirror was badly figured and would not yield the good high power images Tombaugh had hoped it would. Needless to say, the returned mirror with attached note from Carreau left Tombaugh gutted. But thankfully, he didn’t give up. Instead, he vowed to build his very own testing area for any future mirrors he would grind. And it was there and then that Tombaugh plotted an ingenious scheme. He would ask his father for help in the construction of a so called “cyclone cellar” an underground storage area for foodstuffs and a safe haven to take refuge in the event of a tornado strike. His plot worked! After the all important harvest of 1926, with no bull dozers to call upon, Clyde had to dig his own hole; and an enormous one at that; some 24 feet long  by 8 feet wide  and 7 feet deep! He enlisted the help of friendly neighbours to pour 540 cubic feet of concrete to complete the structure replete with floor, walls, windows and even an arched staircase! When completed, this new cellar served as the ideal place to perform testing on his future mirrors, as the air circulating within it was always cool and rather uniform in temperature.

His next mirror, a 7 inch, was made for his uncle Lee, and when tested by Carreau, was found to be rather good! Auspiciously, Comet-Winnecke 1927 VII was ripe for observation, reaching a conspicuous magnitude of +3.5 at the time Tombaugh turned the telescope upon it. Lee was most impressed with the new instrument and immediately bought it from him. With these new funds, Tombaugh began thinking about a personal telescope; an instrument that might allow him to see the great showpieces of the sky and perhaps contribute his own findings to planetology. So in August 1927, he purchased the glass blanks to begin work on this third telescope; a 9 inch Newtonian reflector (featured above) with a focal length of 70 inches (so f/7.8). Grinding the mirror was not without its problems however, for as soon as he got rid of one zone up popped another but he kept working on through the winter and by the spring of 1928 Tombaugh was eventually able to obtain a very smooth figure with an accurate paraboloid, allowing the mirror to sustain very high powers (of the order of 400 diameters), so good enough for all applications he would use it for. By the autumn of 1928, the telescope was ready for first light and with a great sense of excitement he turned it on mighty Jupiter to see how it performed. Well, he needn’t have worried; Clyde watched in sheer amazement as its various markings were seen to drift across the disk. Turning next to Messier 13, the great globular custer in Hercules, he saw a storm of well resolved stars where his little Sears only registered a fuzzy blob. Clyde Tombaugh had realised his dream of owning a serious telescope. Indeed, it was so good that Mr. Carreau offered him a job as a technician in his Wichita workshop. Things were beginning to look up for the enterprising young squire from the back of beyond.

Despite the sheer elation he must surely have felt in designing and building his dream ‘scope, 1928 would not be a year Tombaugh would forget for completely different reasons. Earlier that summer, on June 20 to be precise, disaster struck the Tombaugh farm. A violent thunder storm wreaked havoc with the wheat and oat crops that were, until then, doing so well, owing to a warm spring. In the space of a quarter of an hour they lost it all! And it was so localised that the neighbouring farms went completely unscathed! It was a cruel twist of fate that there and then ended Tombaugh’s ambitions to attend college. It also meant his father had to put off buying that all important combine harvester that would have made life better for everyone. One thing was clear; Tombaugh had had enough of farming. Time to pursue something else.

By the end of 1928, Clyde had amassed an impressive portfolio of planetary drawings and he mailed a selection of them to Lowell Observatory, together with a letter explaining that he wished to be a professional astronomer and inquiring about how best he might go about becoming one. He must have made quite an impression, for what happened next was not only unexpected, it was downright music to his ears! As luck would have it, the administrators at the Observatory were looking for a keen amateur astronomer in good health who would assist in the operation of a new photographic telescope that would shortly be installed there. Needless to say, it set his heart racing!

It was make your mind up time; either become some obscure telescope maker or get a chance to become an astronomer at his favourite Observatory. It was a no brainer! He would accept the post at Lowell, on the understanding that he was to be employed for a trial period of 10 months before being offered the post on a permanent basis. What is more, with a guaranteed monthly salary of $125, he was now earning more than he ever could while working on the family farmstead.

Tombaugh, however, would have to find the means to fund his 1,000 mile rail journey to the American southwest, as well as his initial stay, but he continued working like a Trojan throughout the summer and autumn of that year, operating a combine on a neighbour’s farm, and that earned him the additional cash he badly needed. So, on the morning of January 14 1929, after saying goodbye to his family, he mounted the couch car and settled in for the long, 28 hour journey ahead. As the train pulled off, he must have felt very sad to leave his family, especially since his mother was about to give birth (within 12 hours actually) to the youngest member of the Tombaugh family; little Anita. Indeed, he would not lay eyes on his newly arrived sister for another six months!

Tombaugh, of course, had no idea what was in store for him at Lowell Observatory. What would he be working on? Would he live up to expectations? Would he enjoy the work? All of these questions must have flashed through his mind as the train ventured further and further away from Kansas. Little did he know that he would be getting involved in the hunt for a new planet, long since predicted by the mathematical astronomers who had deduced the presence of a world beyond the orbit of Neptune, based on perturbations in the orbits of the outer planets. And little did he know that this search commenced a full year before Tombaugh was born!

Professor Lowell, deeply depressed by the ridicule he had received for advancing his far fetched idea of an intelligent race of Martians, desperately needed to restore credibility to his work and the status of the Observatory he founded. So in 1905 Lowell spearheaded a new search for Planet X and began acquiring astrographs that would enable a systematic search to be conducted at Mars Hill. By 1912, he had borrowed a state of the art wide angle camera with a 9 inch lens from Swarthmore College’s Sproul Observatory, but after his untimely death in 1916, the camera had to be returned to its rightful owners. Unbeknown to Lowell and his well trained staff, that same camera actually recorded the mysterious planet in a series of exposures captured on March 19 and April 7 1915, but this would not come to light until many years later.

When he arrived at Flagstaff station, he was met by Dr. Vesto M. Slipher, who escorted him by car out of town and up to Mars Hill. As they began to ascend in altitude, he would see the Ponderosa pine trees following the contours of the winding road, now covered in winter ice. Indeed, it was from these pine trees that Lowell built the dome to house the great 24 inch Clark refractor which formed the centre piece of the famous Observatory.

The Clark Telescope Dome on Mars Hill. Image credit: Wiki Commons.

When they arrived, Clyde was introduced to the staff on duty that day; Drs C.O Lampland, E. Pettit and S.B. Nicholson and the Observatory’s handy man, Mr. Jennings. Dr Slipher provided Tombaugh with the details of his job description; he was to operate the new 13 inch f/5.3 astrograph to resume the hunt for Planet X which had come to a halt back in early July of 1916. A smaller 5 inch astrograph was piggybacked atop the main instrument and it took exposures of precisely the same region of sky as the larger astrograph. Indeed, as we shall see, this smaller instrument played an important role in Tombaugh’s seminal discovery.

After the introductions were over, Jennings gave Clyde a lift back down the hill for a spot of breakfast, and in the afternoon Tombaugh would be introduced to the instrument that would soon make him famous; the heavily mounted 13 inch astrograph ready for operation, except for one important detail; it was still without its lens. Indeed, this would not be installed until the middle of February. Designed by Carl Lundin, chief optician to the Alvan Clark & Sons telescope firm, it was a triplet objective designed to capture wide field images of the sky. It was exquisitely well made; one element had very strong curvature which made it very expensive to make, but after it was carefully loaded off the Model T truck, unpacked and mounted, initial tests could be conducted on its imaging potential. A few days later, everything was ready to enable it to take its maiden exposure. The astrograph was pointed at the Sword Handle of Orion and a 30 minute guided exposure conducted. Slipher, Lampland and Tombaugh were present that evening at the telescope. After exposing the photographic plates it was clear that the instrument was working well. The stars were pinpoint sharp, right across the field. Slipher must have let out a big sigh of relief; this expensive piece of kit would be more than capable of detecting Planet X; if it existed, that is!

The 13 inch f/5.3 Lawrence Lowell astrograph featuring the Lundin triplet objective used to conduct the search for Planet X. Image credit; Wiki Commons.

Tombaugh continued his training with the 13 inch astrograph for a couple of months, during which time he sorted out a number of mechanical bugs that might have otherwise jeopardised the entire project. By April 6, it was ready to go.

As one can imagine, finding such a planetary body amid the myriad stars captured by such photographic means was very much akin to finding a proverbial needle in a haystack. The search was confined to a narrow swathe of sky centred on the zodiac, beginning in Cancer but then carrying on the search into Gemini and Leo, and so on. And while each plate typically recorded the spurious disks of hundreds of thousands of stars, it was a great blessing in comparison to the prospect of having to comb through the blizzard of stellar bodies residing closer to the main body of the Milky Way, where stellar population densities shot up to greater than a million per plate in comparison. The strategy adopted by Dr. Slipher was to employ an ingenious device called a blink comparator, invented in 1904 by the German physicist, Carl Pulfrich, working for the famous optics firm, Carl Zeiss Stiftung. The instrument permitted rapid switching from the viewing of one photograph to another, “blinking” back and forth between the two images taken of precisely the same area of the sky but at different times. This allowed the user to more easily detect objects in the night sky that changed position. Of course, other objects besides planets were well known to move relative to the background stars; asteroids, for example. Many of these ‘interlopers’ were to be expected, of course, but they could be weeded out by a consideration of how much they moved in a given time interval. The velocity of a body orbiting the Sun depends on its distance from the Sun. The further away the object lies, the slower its orbital velocity will be and thus the smaller the distance it would be expected to move on a photographic plate.

Because most asteroids reside between the orbits of Mars and Jupiter, they will have a very well defined distribution of velocities all of which correlate with the distance moved on the photographic plates. Objects residing beyond the orbit of Neptune will have correspondingly smaller orbital velocities and will thus show much less relative movement on the photographic plates. So, Tombaugh was trained to look for movements in a certain size range per unit time (of the order of a few millimetres over the course of a week). That said, there were many other sources of error to consider, including the length of exposure of the plates, the effects of atmospheric refraction, dust, clouds, the spurious results attributed to variable stars, as well as false positives owing to defects with the emulsion (equivalent to CCD ‘blooming’ in contemporary digital imaging). In addition, great care had to be made to match the centres of each plate taken at a given time interval.

The Zeiss blink comparator used by Tombaugh with the 13 inch Lowell Astrograph. Image credit: Wiki Commons.

In addition to all of the above parameters, the frequency of blinking had to be fine tuned for optimal results. This was found to be about 3 Hz (i.e. 3 times per second).  Anything greater than 10Hz would introduce an effect known as ‘persistence of vision’, where the eye would start to register considerably less motion. Less that 2Hz and the time realistically needed to conduct the searches would have to have been greatly increased. In this way, every inch of these plates were to be examined microscopically, requiring great concentration to carry it out effectively.

In consideration of all of this, Slipher was acutely aware that the odds of success were still very low and, as a result, the staff were told to keep ‘schtum’ about the details of the project, for fear of more ridicule from either the gallous press or the greater scientific community. Indeed, this much was acknowledged by Professor Lowell at the outset of the project, and he accordingly encouraged his staff to pursue other avenues of research so as to shore up the amount of ‘conventional’ data produced by the astronomers on Mars Hill. Overall, Tombaugh conceded that his new post was far from glamorous. It required long hours, and 100 per cent commitment in sometimes freezing conditions that would tax the hardiest soul.

On bright, moonlit nights, no exposures could be made, and Tombaugh was therefore free to catch up with other duties, ranging from the mundane but no less essential, such as stoking the furnaces with logs and shovelling snow, to the specialised, like mounting and developing the photographic plates, operating the blinker and keeping detailed written records of events as they unfolded, and so on. There was also time for leisurely observing. One of the treats Clyde enjoyed during these moonlit spells was the use of the great refractor for the visual inspection of the planets. Though V.M. Slipher was a formidable theorist and spectroscopist, he was also a highly skilled visual observer, having conducted many years of observations through the 24 inch Clark.

Records show that he would regularly employ a yellow filter at the eyepiece to supress the secondary spectrum produced by the achromatic doublet lens while observing Mars at high power. Others preferred red or orange filters but Slipher felt the transmitted yellow light preserved the natural colours of the planet best. Typically powers were kept below 500 diameters for planetary work on the great refractor (double star mensuration would often require more but the instrument was not used for such work, at least during the time Tombaugh was at the Observatory). It was through his in depth discussion with Slipher that Tombaugh learned that Percival Lowell was accustomed to stopping down the aperture of the 24 inch to 16 inches some 90 per cent of the time it was being used! Tombaugh also practiced this technique rather often with the large refractor but he recalled many occasions where he saw the alleged canals, more or less, as Lowell and Slipher had recorded them. But he also added that when he finally had a chance to examine the Red Planet through the considerably more powerful 82 inch reflector (dedicated in 1939) at McDonald Observatory, Fort Davis, Texas, where the seeing conditions were often better, the canals disappeared into a series of dots that the eye would naturally try to join in a smaller instrument. Tombaugh most certainly knew that Lowell’s canals were a sweet illusion.

Percival Lowell at the 24 inch Clark, conducting daylight observations of Venus. Image credit: Wiki Commons.

It is also noteworthy that Tombaugh did not revere the great refractor, or any other kind of  telescope for that matter. Indeed, one biographer noted how Tombaugh would frequently argue with the other staff astronomers that a Newtonian reflector could equal or exceed the performance of the best refractors, and without generating a colour error. His peers were biased though, as they only had the 42 inch reflector at Lowell Observatory to compare the great refractor with; and that was hardly a fair comparison as it was badly mounted below ground and as a result suffered from inferior seeing more frequently than the refractor! Indeed, the conclusion reached by Tombaugh was also arrived at by the late Professor E.E. Barnard, whilst comparing the planetary images garnered with the great 36 and 40 inch Clark refractors, with which he was intimately acquainted, to the newly arrived 60 inch reflector atop Mount Wilson, which saw first light in early December 1908.

The morning of February 18, 1930, was rather overcast while Clyde went about his routine work at the Observatory. This morning he was comparing two plates, each consisting of 10 minute exposures, taken near the star Delta Geminorum; one dated to the evening of January 23 (no. 165) and the other, to January 29 ( no. 171) 1930. Loading the plates into the blink comparator he noticed a shift in position of a body that looked very promising. It had shifted by 3.5mm; in the ballpark of the trans Neptunian object. But he wasn’t getting excited just yet. Tombaugh was far too cautious to jump to any conclusions before he carried out his battery of checks. Was it a blooming artefact?  Was it a variable star? Was one plate overexposed relative to the other? All of these had to be investigated but sure enough, the object looked solid. Now he was getting excited but still doubted himself. Then he thought of the smaller 5” astrograph, which should have recorded the same phenomenon. So he had those plates exposed and though the images were considerably fainter, his microscopic examination showed the same blinking! A tingle ran down his spine as he contemplated the evidence; he was now 100 per cent sure that he had discovered Planet X.

Now he had to tell someone.

Dr. Lampland was working in his office adjacent to Clyde’s. Later he would recall that something seemed amiss that morning as the sound of the blink comparator fell silent for a good half an hour. Tombaugh shuffled across the corridor and knocked on Lampland’s office door. “Come in,” Lampland shouted. Quietly opening the door, Tombaugh popped his head round and said, “I think I’ve found Planet X!” With this, Lampland jumped out of his seat and darted across the corridor to check the data for himself. As Tombaugh described the drill of checks he had carried out, Lampland looked very impressed. It was time to inform Dr. Slipher. So, excitedly, Tombaugh made his way down the long corridor leading to his office. “Dr. Slipher,” he said, “I have found your Planet X.” With a lingering stare, Slipher charged out of the office to examine the evidence for himself. For another hour the three men poured over the data and all were in agreement that it was a bona fide world beyond the orbit of the 8th planet.

It’s position among the stars of Gemini was also significant. Professor Lowell, proficient in celestial mechanics, had initially calculated the locus of Planet X to be in Libra, but upon later revisions, he revised this, first to eastern Taurus before finally settling on Gemini. Lowell had at last been vindicated, albeit posthumously. Dr. Slipher was in no hurry to announce the news just yet though. He was far too cautious for that. Thinking ahead, he ordered Tombaugh to take another set of exposures of the region near Delta Geminorum with the 13 inch astrograph, while Lampland was to obtain more precise positional data on the object using the 42 inch reflector. The comparator was fitted with a higher power microscope in order to obtain more accurate data on the object’s kinematics in order to compute its orbit.  On the evening of Wednesday February 20, Slipher, Lampland and Tombaugh opened the dome of the great refractor and pointed it at the new object. What they saw disappointed them. It was dim (of the 15th magnitude) and was completely indistinguishable from the other stars in the field! If this was a new world, it was very small. Indeed, the uninspiring telescopic sight of the planet induced a degree of paranoia in Tombaugh. What if this wasn’t Planet X after all? Maybe if he searched some more he’d find a larger object, more befitting of the icy giant worlds discovered by Sir William Herschel, Urbain Le Verrier and John Couch Adams?

As the days passed by, some other scientists were notified for consultative purposes, including Vesto’s brother and fellow astronomer, Earl C. Slipher, and Harlow Shapley, the then Director of Harvard College Observatory, in strict confidence that it would, for now, go no further. One date seemed especially appropriate; March 13 1930. It was Percival Lowell’s birthday; the highly esteemed persona who had given birth to the dream. It was also the 149th anniversary of Herschel’s discovery of Uranus. In the meantime, they would get their heads down and find out as much as possible about this small new world at the edge of the known Solar System.

Tombaugh went to work making a better estimate of the object’s magnitude, which he revised to magnitude 15.25. To get a better fix on its orbit, the staff re-examined plates from 1929. If they could find an earlier position of Planet X, they reasoned, they would have a larger arc to work with and hence be able to pin down its orbit with greater accuracy. But time was seriously against them and the search did not yield anything. The faithful day had arrived. Shortly after midnight on March 13, Tombaugh, Slipher met in the secretary’s office at Lowell Observatory and despatched a telegram to Harlow Shapley, who in turn immediately informed the International Union’s Bureau in Copenhagen. In addition to these telegrams, the Observatory issued a circular entitled, “The Discovery of a Solar System Body Apparently Trans Neptunian.” The circular gave some background to the project, how it was spearheaded by Lowell in 1905, discovered by Tombaugh and was being followed up and photographed regularly by Lampland. In addition, the celestial coordinates of its position at discovery was issued.

By the evening of March 13, the newspapers got wind of the story, and with that, the usual hodgepodge of misinformation.  Some didn’t metion Tombaugh at all, while in other stories his named was lost amongst a dozen other characters associated with the search since 1905. Back home in Burdett, Kansas, journalists from the local newspaper came out to the Tombaugh farm to get some background information for a cover story. In the space of a few hours the name “Clyde Tombaugh” was on the lips of everyone in the State and in the days that followed, he became an international ‘wonder boy’. But the announcement was also accepted with quite a bit of cynicism, especially from the professional community. Some astronomers questioned whether it really was a planet or merely a slow moving asteroid or comet near its aphelion. Others complained that the Lowell astronomers could not yet definitively say whether it was a trans Neptunian world without issuing its orbital details; data they had not yet been amassed with any accuracy. All of this upwelled troubling thoughts in Tombaugh’s young mind; the thrill of discovery was now tainted with lingering doubts and feelings of inadequacy.

The staff at Lowell Observatory were wise not to issue the precise coordinates of Planet X, as everyone and their grandmother was trying to find it. By June 1930, two further plates were recovered featuring the object in March and April 1915 and an intriguing record emerged from astronomers based in Uccle Observatory, Belgium, who had allegedly recovered the same object on a photographic plate dated to January 27 1927. These data greatly assisted the celestial mechanicians to place Planet X’s orbit on a much sounder footing. This was no comet; it was a real planet.

The appellation “Planet X” of course, would not satisfy a curious public, so the matter of bestowing an official name on the planet grew in urgency. Percival Lowell’s widow, Constance, suggested the name “Zeus” but upon later reflection humbly (no, not really!) offered “Percival,” and then, in a somewhat egotistical vein, “Constance,” which infuriated Tombaugh. However, conservatism had the last word, and so in keeping with the tradition of the names given to the other planets in our Solar System, Planet X would have to be Romanised. Many suggestions were forwarded, including Minerva and Cronus, but it was the suggestion made by an 11 year old English girl, herself a keen student of classical mythology, Venetia Burney, who suggested “Pluto”; after the Roman god of the underworld. What’s more, as V.M. Slipher pointed out, Pluto’s lettering started with the initials of Percival Lowell’s name, which sated the desire of the senior staff at Lowell Observatory  to ‘canonize’ their founding father. The name resonated with the public too. So from May 1 1930 Planet X was now known as Pluto.

The discovery of Pluto suggested to astronomers that there may be other objects lurking in the shadows beyond Neptune’s orbit. Many astronomers begun such searches and it soon became incumbent upon the staff at Lowell Observatory to resume further searches. This Tombaugh did for much of that late Spring. During this time, many more visitors were making the pilgrimmage to Mars Hill and Clyde was asked to submit popularised articles to various ‘highbrow’ periodicals, which he carried out with great diligence and enthusiasm. He even got a personal visit from Constance Lowell, immaculately turned out all in funeral black, like some grotesque parody of Queen Victoria of Great Britain. Constance was by all accounts, a snooty and overpowering character who never really accepted Tombaugh as the discoverer of “her husband’s planet.”

With the advent of the rainy season in July 1930, Clyde was granted three weeks leave to go home and see his family in Kansas and to finally meet his baby sister for the first time. It was a joyous reunion for the young man who made it to the big time, and like Cincinnatus of old, laying down the bloodied cloak of a soldier to embrace the ploughshare, so too did Tombaugh relish the prospect of returning to the wheat and the threshing floor on his family’s farmstead. It was a breath of fresh air for the famous farmer turned astronomer. He also got to use his dearly missed 9 inch reflector for bouts of recreational astronomy under summer skies.

After his well earned vacation, Tombaugh returned to Lowell Observatory to carry on the search for new trans Neptunian objects. If anything, the next few years were even more taxing than before, as the search became more extensive, covering much larger areas of sky.  But although his work brought up many false positive results, he did have the pleasure of clarifying the nature of one object, a globular cluster, NGC 5694, in Hydra, first identified by Sir William Herschel in May 1784 as a fuzzy star. It was also a time where Tombaugh ‘evangelised’ his formally trained colleagues, constructing a number of reflecting telescopes for casual sweeping. Indeed, Clyde is rumoured to have constructed the first ultrarich field reflector in the United States; a 5 inch f/4 instrument which enthralled Lampland, Slipher and others. As a personal telescope though, Tombaugh was a bit more discriminating. A relative aperture of 5 was just about acceptable to him on account of the amount of coma it showed at the edge of the field. But f/6 or slower was far superior in his opinion. Indeed, during these years, he would argue that a long focus Cassegrain reflector would knock the socks off the 24 inch refractor and he was even able to definitively offer a reason why the 42 inch reflector erected west of the great refractor gave less good visual results on most occasions. The mounting, he discovered, was shoddy, and because it was erected just below ground level it suffered far more from thermals. Still, his recommendations fell on deaf ears. The 24 inch was elevated to the status of a ‘holy relic’ and no amount of reasoned argument was enough to sway Lowell’s learned disciples.

Indeed, Tombaugh conducted his own set of experiments on the great refractor on Lowell’s favourite target, Mars, and his conclusions were very revealing. At the powers Lowell used (typically 400x) with a stopped down lens, Tombaugh was absolutely certain that he saw the canals as Lowell reported them. But he felt that Lowell was quite unscientific in his choice of magnification. Specifically, when the power was increased some more, the straight canals lost their linearity. Lowell was obsessed with canals though. He desperately wanted them to exist, and even saw them on Venus, Mercury as well as on the Galilean satellites of Jupiter!

Tombaugh also conceded that the dramatic seasonal changes on Mars as seen through the great refractor did often look like the march of green vegetation, with some canals appearing and disappearing from one apparition to the next. This was a common perception though, as astronomers were completely open to the idea that some form of plant life could eke out a living on the Red Planet right up until the advent of the Space Age.

Despite Tombaugh’s international fame, it was not accompanied by wealth. Nor did he actively seek it. The University of Kansas offered Tombaugh a four year Edward Emory Slosson Scholarship in 1931, the first of its kind, but he chose to postpone his University studies for a year in order to complete the ambitious survey he was assigned to. It was while studying for his Bachelors degree in astronomy (graduating in 1936) that he met his future wife, Patricia Edson, who also graduated with an honours degree in the Liberal Arts. ‘Patsy,’ seven years his younger, married Clyde in June 1934 and accompanied her husband back to his accommodation at Lowell Observatory. Tombaugh went on to earn a Masters degree in astronomy at the same University in 1938. His employers at Lowell Observatory were only too happy to see him complete his formal education, as they felt that would make him a more ‘rounded’ scientist.

Except for a year long hiatus to complete his Master’s degree in 1938, Tombaugh resumed his photographic patrol of the sky with the 13 inch astrograph atop Mars Hill, Arizona, but was fully cognizant of the rapid developments the better equipped observatories were making, especially with the giant 60 and 100 inch reflecting telescopes on Mount Wilson in California. Tombaugh began to think of other ways to use the huge quantities of image data captured by his photographic surveys. It occurred to him that the same data could be used to uncover new variable stars, asteroids and comets and sure enough it did. In addition though, it brought dividends concerning the distribution of the spiral nebulae, the ‘Island Universes’ beyond the confines of the Milky Way. Specifically, Tombaugh uncovered a striking increase in the number of galaxies in the Great Square of Pegasus and extending eastward as far as Perseus. V.M. Slipher was very excited about this discovery and encouraged Clyde to write up a paper on his findings, which he presented at the Astronomical Society of the Pacific, which convened in Denver, Colorado, in June of 1937. Tombaugh uncovered evidence that galaxies too are arranged into higher order structures like clusters and super clusters, stoking a brand new line of galactic astronomy that continues apace to this day. But the rise of Nazi Germany in Europe and the jostling for power in the Pacific Basin was about to trigger a World War that would change everyone’s priorities.

The outbreak of World War II brought sweeping changes to the lives of millions of people across the globe. And Clyde’s circumstances were no different, especially after the events of Pearl Harbor on December 7 1941. In February 1943, while still officially working at the Lowell Observatory, he was invited to teach a physics class at Arizona State Teacher’s College at Flagstaff, a post which he accepted but only briefly held, as the U.S. Navy headhunted him to teach navigation to a new generation of mariners at Northern Arizona University. Although he felt unqualified to take the post, the navy commander in correspondence with Tombaugh reassured him that he was, especially since he had by now gained the trigonometrical skills in his astronomy training to grapple with the course content. He felt it his duty to accept the new job, postponing, for now at least, his work with Lowell Observatory. Then, in 1944, Tombaugh was approached by the University of California at Los Angeles (UCLA), which offered him a decent wage for teaching two semesters of astronomy classes to undergraduates. He accepted that post and enjoyed his time in California.

By this time however, tensions were being strained with his relationship with the staff at Lowell Observatory, who felt that his skills were now dispensable. Slipher was also showing outward signs of jealousy toward Tombaugh, who, in his opinion, had stolen the show with his sole claim on Pluto. He was formally dismissed from the institution in 1945.  It was hard to know which way to go for the Tombaughs in the immediate aftermath of the War but it was Patsy’s brother, James Edson, who provided the way forward. Having just secured a good job at White Sands Missile Range, New Mexico, where the U.S. military were developing their space age defence technologies. As part of their ambitious program, they needed someone to operate a new long focal length telescope to image missiles in flight. Tombaugh’s expertise in practical and theoretical optics made him just the man for the job. The money wasn’t bad either, all the more important to support their two new arrivals, Anette and Alden.  Clyde was to work and live at the base and from October 1946, Patsy and her two kids stayed at rented accommodation in the nearby town of Las Crusces. From the outset, Clyde’s training as a telescopist brought dividends to his new employers, by greatly improving the tracking capability of V2 rockets. For example, he soon discovered that one of the major reasons why the missiles could not be tracked over long distances was because of the times at which they were launched; usually 11 am. Tombaugh pointed out that there was so much turbulence in the air at this time that it would greatly impede optical telemetry efforts. He suggested instead that they change the time of launch of the V2 missiles to either the early morning or early evening when thermals were much less of an issue. He also suggested that instead of using the traditional achromatic telescopes for tracking, they ought to build a large aperture reflecting telescope (16 inch f/6), which offered better optics (owing to the lack of chromatic aberration) at much reduced expense.

His almost overnight success at White Sands military base gave him a level of security he never enjoyed in the stuffy intellectual climate he experienced toward the end of his days at Lowell Observatory. His comrades at the base elevated him to the status of a hero and he was constantly in demand to recount his story of how he discovered the furthest planet known in the Solar System. And a good, regular salary allowed the Tombaugh’s to purchase their first house at 636 South Almeda, Las Cruces, albeit in a rather dilapidated state (a new roof being chief among the repairs needed). This was to be their home for the next two decades. By 1950, Tombaugh had fulfilled all the major technical tasks his employers had asked of him and he was thereafter able to return to the hobby which had launched his career. He wrote his father back in Kansas, requesting him to send on his old 9 inch reflector so that he resume his amateur work. It was a round this time also that he started thinking about the planets again, particularly Mars, which had captivated him ever since his youth. Accordingly, he wrote up and published a couple of interesting research papers predicting the presence of impact craters on the surface of Mars, owing to its very thin atmosphere and its greater proximity to the asteroid belt. This work presaged the findings of Mariner IV, which in 1965 showed conclusively that the Red Planet was peppered with craters of all shapes and sizes, making it more like the Moon than anything else.

It was in 1953 that Tombaugh became personally involved in the search for Near Earth Objects and/or small, natural satellites, to assist the government in establishing how safe it was to launch spacecraft into near Earth space. In essence, the nature of these searches were the same as those Tombaugh carried out in his earlier planet searching days at Lowell Observatory, although since the objects were so much closer to our planet, they would move much larger distances on photographic plates per unit time. Ironically, one of the best instruments for doing this kind of work was the 13 inch Lawrence Lowell telescope atop Mars Hill. Tombaugh found himself commuting between Flagstaff and White Sands, only this time he was fully funded by the U.S. military with assistants under his command. The cash starved adminstrators on Mars Hill were only too happy to acquiesce. While there was some cause to keep aspects of the project secret, Tombaugh publicly announced at a meteor conference held at Los Angeles in 1957 that the four year long search had been unsuccessful.

The 1950s represented a time of unprecedented scientific progress. Literally anything was possible. Cures for cancer were just around the corner, and new drugs had conquered nearly all diseases that had plagued humankind for millennia. Now Man was setting his sights on the heavens and the discoveries that might lie in our future. Although Tombaugh never studied the subject, he blindly believed in Darwinian evolution and thus fully expected there to be intelligent life elsewhere in the Universe. Curiously, this happened around the same time he down played his traditional Christian beliefs and embraced the all singing, all dancing, Unitarian Universalist (read anything goes) church. Intriguingly, this dovetailed with his growing interest in Unidentified Flying Objects (UFOs). Indeed, Tombaugh not only believed that UFOs were a manifestation of extraterrestrial intelligence, he actually reported seeing ‘six to eight’ such objects on August 20 1949 near his home at Las Cruces, New Mexico. What is more, it is also known that he offered to spearhead a new project for the military to capture these objects with the telemetric technology available to him at White Sands.

What an extraordinary convergence of ideologies! For the record, the consensus opinion among secular scientists who have studied the phenomenon over several decades concluded that UFOs have a strong demonic dimension.

From 1955 until his retirement in 1973, Tombaugh joined the academic staff at New Mexico State University, where he took up a research interest close to his heart; the visual and photographic monitoring of planets which came into effect around 1958. Calling it the Planetary Patrol and Study Project, Tombaugh and his colleague Bradford Smith (who would later become an imaging scientist with the Mariner and Voyager missions), set up a fine 12 inch f/6.7 Newtonian just off campus. Funded by small grants from the National Science Foundation, it began taking images of the major planets across a broad range of wavelengths from the ultraviolet right the way through to the infrared. The instrument was later moved to an even better site in the nearby Tortugas Mountains. In addition to these multispectral photographic studies, regular visual drawings were made of Jupiter, Saturn, Mars and Venus. Collectively, the data was used to assist NASA’s ambitious Mariner and (later) Pioneer spacecraft program. Optically, the 12 inch was reputed to be very fine indeed. To get an idea of how good it was, a visiting astronomer from Lowell Observatory had the pleasure of using it for a short spell and he declared that its images were sharper and clearer than the best images rendered with the old 24 inch Clark refractor on Mars Hill.

The Mariner missions to the planets were received with mixed blessings by Tombaugh. On the one hand, he was delighted that the Mariner IV spacecraft had beamed back solid evidence that the Red Planet was littered with craters, but was very disappointed that no evidence for Martian vegetation was forthcoming from the same mission. Because of his misplaced faith in evolution, Tombaugh was sure that the ‘waves of darkening’ he observed through his telescopes over the years were the manifestation of plant life and never really gave up hope that one day they would discover life there.

As well as his beloved 9 inch reflector, Tombaugh dusted down an old project he had begun in the 1930s and early 1940s involving a substantially larger personal telescope; a 16 inch f/10 Newtonian. Indeed, the mirror had been ground by 1944 but because of work commitments, he had to foreswear until 1960, when he finally completed the telescope. By this time the Tombaughs had moved into a larger and more opulent home setting at the southeastern apex of Las Crusces. He donated this instrument, which had an Honest John Booster as a tube, together with a very heavy equatorial mount to the newly founded Las Crusces Astronomical Society.

All who assessed the quality of the work conducted with the 12 inch for the Planetary Patrol Project, agreed that it was of the highest quality and of great importance to the developing space program. Indeed, Tombaugh was able to persuade NASA to provide funding for not one, but two 24 inch reflectors; one to be dedicated to planetary studies and the other to extend stellar and extragalactic research. The archives at NMSU have preserved about a million photographs of which more than half were taken of Jupiter. By 1961, the Planetary Patrol Project and Study Group consisted of a team of five scientists and it was about this time that NMSU officials approached Tombaugh to set up a brand new department within the University system. Although he was reluctant to do so, Tombaugh eventually amalgamated the originally small Department of Geography & Geology into a new and substantially larger Department of Earth Sciences and Astronomy.

Tombaugh’s retirement years were long and productive, and not surprisingly, he was approached by all and sundry to write his memoirs of his extraordinary career, as well as his philosophy of life. Interestingly, he vehemently denied, despite the battery of hard physical evidence in support of it,  that the Universe had a beginning, as that would give too much credence to the Biblical narrative, which clearly (and uniquely) states in its opening line the prophetic words:

In the beginning God created the Heaven and the earth.

Genesis 1:1 (from Tombaugh’s copy of the Authorized King James Version)

Indeed, for a man who supposedly eschewed ‘the illogical,’ his denial of Big Bang Cosmology was somewhat hypocritical.

And although his hands were associated with many an amateur telescope, he enjoyed deep sky observing with a 10 inch f/5 Newtonian. His iconic 9 inch reflector was donated to the Smithsonian Institution as part of the display dedicated to the “Nation’s Attic.” He collaborated with Sir Patrick Moore on a new book chronicling his discovery of Pluto; Out of Darkness, The Planet Pluto; which was published in 1980, the highlights of which were serialised in a series of Sky & Telescope articles appearing about the same time. Much of his retirement days were also spent travelling as guest speaker at a number of amateur gatherings the length and breadth of the country. Indeed, as one biographer noted, he was busier during these years than he had ever been while in full time employment. Many honours were bestowed upon him, and none undeservedly, including a kindergarten school at Las Crusces, an entire Observatory at NMSU and at the University of Kansas, as well as the Jackson–Gwilt Medal of the Royal Astronomical Society.

But his career was tinged with a great deal of personal sadness, as his most famous discovery was progressively demoted in importance owing to the discovery of several other trans Neptunian objects, most notable of which was 1992 QB1. The reality was that Tombaugh had inadvertently opened a veritable Pandora’s Box of new objects residing in the Solar System’s Kuiper Belt. And, to add insult to injury, there was growing talk that the discovery of more and more Kuiper Belt Objects (KBOs) would almost certainly mean that Pluto would have to be downgraded to the status of the first discovered member of a new group of ‘dwarf planets.’

The dwarf planet 134340 Pluto, as imaged by the New Horizons spacecraft on July 14 2015. Image credit: Wiki Commons.

Tombaugh passed away quietly in his wheelchair on Friday January 17th 1997, survived by his wife and two children. Less than ten years later, the 26th Assembly of the International Astronomical Union voted, predictably, to reclassify Pluto as a dwarf planet (134340 Pluto), and so the Solar System went back to having eight members. After his cremation, a small part of his ashes (30g) were placed inside a vial that was carried by NASA’s New Horizon Spacecraft, which visited Pluto and its entourage of moons in July 2015, beaming back a wealth of high resolution images of this distant ice world on the edge of the Solar System. One of its major features, a vast ice field, was also named in his honour; Tombaugh Regio.

Clyde William Tombaugh (1906 –1997); a life in science.

References & Further Reading

Levy, D.H. Clyde Tombaugh, Discover of Planet Pluto, Sky Publishing Corp, 2006.

Tombaugh, C. & Moore, P., Into the Darkness, The Planet Pluto, Harrisburg, Pennsylvania. Stackpole, 1980.

Sheehan, W. The Immortal Fire Within, The Life and Work of Edward Emerson Barnard, Cambridge University Press, 1995.

Ashbrook, J., The Astronomical Scrapbook, Sky Publishing, 1984.

Ross, H. Samples, K & Clark, M. Lights in the Sky and Little Green Men, NavPress Publishing Group, 2002.

Steiger, B., Project Bluebook, Ballatine Books, 1976.

Menzel, D. & Boyd, L.G.,The World of Flying Saucers: A scientific examination of a major myth of the space age, Doubleday, 1963.

Biographical Link: https://carlkop.home.xs4all.nl/clyde.html

 

Dr. Neil English is author of several books on amateur telescopic astronomy and is currently writing a new work entitled: Tales from the Golden Age of Astronomy, published in the spring of 2018.

 


De Fideli.

Tales from the Golden Age: A Short Commentary on Walter Scott Houston’s “Deep Sky Wonders” Part II

A Distillation of observing notes from the late Walter Scott Houston(1912–93)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Chapter 8: August (continued)

Summer lies hot and tranquil on the land. The gigantic storms of winter and the turbulent atmosphere that accompanies them are only memories now. At this time of year the seeing is steady all night.

West of the Meridian in late evening lie the great star fields dancing with the brilliance of Sagittarius, Scorpius and Scutum. The eastern sky, however, is a virtual desert of bright stars. The Great Square of Pegasus has little to offer the naked eye observer, and Equuleus is likewise dim. On nights when a bright Moon floods the heavens with its golden light, the eastern sky appears almost devoid of stars. Near the meridian, however, in the small constellation of Delphinus the Dolphin.

pp 187

I can almost imagine Scotty setiing up at sunset, his charts in one hand, his tobacco pipe in the other, pensive, waiting for the curtain of darkness to draw on the landscape. August is a very special time in my own seasonal viewing, as it represents the end of a long period of summer twilight, when the sky never becomes truly dark. Running from late May to the end of July, year in, year out, the arrival of true darkness in early August is an event to be celebrated!

As Scotty mentions, the summer months generally bring the best seeing in the year, and that’s true across many areas of Europe too, despite the encroach of biting insects; Scotty had the mosquito, here it is the midge fly. Despite its diminutive size, Delphinus offers a fair amount of deep sky real estate for the enthusiastic star gazer and Scotty does a sterling job highlighting them for his readership.

Scotty says that he developed a “fondness” for Delphinus because of its richness in variable stars, which he enthusiastically monitored in the early days of his work for the AAVSO. On page 188 he points out that the constellation is home to a number of very fetching double stars that are accessible with binoculars or a small telescope. Arguably the most celebrated is Gamma Delphini, which marks the northeastern corner of the Dolphin. Through my 80mm f/5 achromatic telescope it is easily resolved at 50x showing a lovely golden primary and pale yellow secondary separated by about 12″ of dark sky.  Scotty says they’ve hardly moved since the system was first surveyed in 1830 by Wilhelm Struve.

Houston also mentions the much more challenging binary system; Beta Delphini ( magnitudes 4.0 and 4.9)  the secondary of which exhibits an apastron of 0.6″ and periastron of 0.2.” This system was first discovered by S.W Burnham in August 1873 using his 6 inch Clark refractor. Scotty informs us that Burnham was lucky enough to examine the stars near their maximum separation. Then on page 189 he delivers another invaluable account of his own efforts to resolve this pair using his old Newtonian;

In 1950 I examined the star with my newly completed 10 inch reflector. Then the separation was near a maximum of 0.6″ with the companion due north of the primary. My first attempts to split the pair failed because the companion was lost in the diffraction spike caused by the telescope’s secondary mirror holder. Success came only after rotating the tube 45 degrees in its cradle to shift the position of the spike.

pp 189.

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Author’s note: I have spent the past few years carefully studying the properties of Newtonian reflectors in regard to their ability to split double stars. My findings showed that they were excellent instruments in pursuing this high resolution work, which has been traditionally associated with equatorially mounted classical refractors, and more recently in the promotion of very expensive apochromatic refractors. My own instrument of choice in the divination of difficult double stars, including sub arc second pairs is a 20.4cm f/6 Dobsonian (affectionately called ‘Octavius’) with a 22 per cent central obstruction. This work has instilled in me a deep respect for these telescopes that I am eager to share with my peers across the world. I give thanks both to Scotty and to Stephen James O’ Meara for including this material from his old Sky & Telescope columns and this book, respectively.

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Octavius; the author’s tried and trusted 8″ f/6 Newtonian on its ‘pushto’ mount.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Delphinus is also home to a number of rather lacklustre deep space objects. A challenge for larger apertures is provided with the tiny, compact globular cluster NGC 7006 (magnitude10.5), found by panning some 3.5 degrees east of Gamma Delphini. In my 8 inch telescope, NGC 7006 remains unresolved at 200x; more like a fuzzy snowball than anything else. Indeed, Scotty maintains that it remains unresolved in all but the largest instruments, and I would tend to agree. The reason is the enormous distance of this globular; now estimated to be about 140,000 light years (Scotty quotes 110,000 light years).

In the last couple of pages, Houston  discusses a few other objects of note in Delphinus, including the globular cluster, NGC 6934, the planetary nebula, NGC 6905, and the galaxy, NGC 6956. What is noteworthy is that Scotty weaves the experiences of other observers into his narrative, including Barbara Wilson, Philip Harrington, as well as celebrated authorities from yesteryear, such as the Reverend T.W. Webb (see pages 190 through 191).

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Chapter 9: September

Scotty begins this month’s adventures in the oft overlooked constellation of Lacerta, the Lizard. Sandwiched between the larger constellations of Cynus to its west and Pegasus to its east, Lacerta is one of the ‘new’ constellations introduced by Johannes Hevelius in 1687. Scotty suggests we shouldn’t overlook Lacerta owing to the fact that since 1910, three novae have blazed forth from within its borders, so who knows when the next one will come.  First up, Scotty draws our attention a very picturesque open cluster of stars for binoculars or small telescopes; NGC 7243. You’ll find this cluster a little over 2.5 degrees west of Lacerta’s brightest luminary, Alpha Lacertae. Here’s how Scotty describes this cluster:

The cluster stands out especially well from the stellar background when I stop down my 4 inch Clark refractor down to 1.8 inches. According to Revue de constellations by R. Sagot and Jean Texereau, NGC 7243 in a 4 inch at about 50x is a rich traingular cluster of many stars between 9th and 11 th magnitude. The number of stars increases from about 15 in a 2 inch to 60 in an 8 inch. I found no define shape in a 12 inch recently, but counted at least 80 stars within a 1/3 of a degree area. Look for a wide double at the luster’s center, particularly if you have a 6 inch or larger telescope.

pp 197.

The surprisingly rich open cluster, NGC 7243, in Lacerta.

 

 

Author’s note: This cluster is indeed a fine sight in 15 x 70 binoculars or a small telescope. My 80mm f/5 telescope reveals about 30 members at 50x, but nearly double that in my 8 inch reflector. Larger telescopes show more, growing to well over 100 in a 12 inch instrument, though the precise number also depends on the magnifications employed. Best to experiment with NGC 7243 to see what’s what.

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4 degrees directly south of NGC 7243 is NGC 7209, described on the bottom of page 197 and 198.

At midnorthern latitudes, the grand constellation of Cygnus rises high in the sky for exploration during September. On pages 200 to 210, Twinky covers much of its rich cache of deep sky treasures. After providing some interesting background on the constellation, Scotty launches into a wonderful discussion on the North American Nebula (NGC 7000), an enormous emission nebula located about three degrees east of the bright summer star, Deneb.

The huge and sprawling North American Nebula ( NGC 7000); a visble and infrared presentation. Image credit: Wiki Commons.

 

 

From my location, the skies are just dark enough to enable me to see the brightest parts of this emission nebula without the aid of a nebular filter. With a 32mm Plossl eyepiece delivering the large true field possible with a 1.25″ ocular, my 80mmf/5 achromatic delivers a wonderful field some 4 degrees wide at 13x. Scotty points out that NGC 7000 is an object celebrated more in modern times than in the past (see page 202). He attributes this to the rather restricted fields of the best telescopes of yesteryear, which tended to have very long focal lengths and the relative paucity of good, wide angle eyepieces. Indeed, in the darkest skies that Britain can offer, you can indeed make out the North American Nebula with the naked eye. Indeed, I last observed NGC 7000 in August of 2016 during a trip to the remote island of Skye, off the northwest coast of Scotland.

From here, Scotty moves on to M39, a nice open cluster for binoculars or small telescopes right up at the northern end of the constellation. To see it, centre your telescope on 4th magnitude, Rho Cygni, and move a little under 3 degrees further north, where it will appear in your low power telescopic field. Covering an area about half a degree wide, my tiny 3.1 glass at 13x reveals about twenty members, scattered haphazardly across the field. Scotty says he noticed a dark streak running about 5 dgrees east southeastward  from M39. A dark dust lane? What do you think?

Messier 39 in northern Cygnus; a nice binocular and/or small telescope object.Image credit:Wiki Commons.

In discussing dark lanes and nebulosity, Scotty mentions something very curious at the top of page 203:

The detection of dark nebulosity depends on many factors. I lean toward using long focus instruments because my experience has shown that they tend to scatter less light and provide a higher contrast image than do rich field telescopes. I have had some dramatic views of dark objects with my old 10 inch f/8.5 Newtonian reflector and the 12 inch f/17 Porter turret telescope in Springfield, Vermont.

pp 203.

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Author’s note: If you actually read through the book, you’ll notice that Scotty also makes the same claims for the images served up by his 4″ f/15 Clark refractor.The common denominator, so far as I can see, is the long native focal length of both his aforementioned  reflecting telescope and the classical achromat. Cassegrain and compound (catadioptric) telescopes don’t really count, as the primary mirrors are quite fast (typically  f/2 to f/4). The latter’s high net f ratio relies on the magnifying effects of the secondary mirrors.

What do you think?

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Pages 204 through 208 covers the weird and wonderful Veil Nebula in Cygus, an ancient supernova remnant which occured 15,000 years ago. Scotty describes it thus:

…..a broken bubble of luminous gas some 2 degrees in diameter. Although ignored by generations of telescope users, in the past 30 years the veil has progressed from a difficult test object to a reasonable target for anything from binoculars to the largest amateur telescopes. It is an excellent nebula for trainig the eye, perhaps the most important observing ” accessory,” to help us get the most out of the telescope we are using.

pp 205

Scotty informs us that the brightest parts of the nebula were discovered by Sir William Herschel back in 1784 during one of his sweeps using his homemade 18.25 inch speculum.  The Veil is partitioned into two distinct regions, east and west, with the former (NGC 6992) being slightly more easy to see. The eastern Veil (NGC 6992 & 6995) is found about 2.7 degrees northeast of the star 52 Cygni (an excellent colour constrast double for small telescopes). The western segment (NGC 6960) can be detected snaking its way past 52 Cygni. Getting to the spot in the sky where the Veil is located is the easy part but seeing it is quite a different matter! You’ll need very dark and transparent skies to have the best chance of seeing it with a backyard ‘scope without a nebular filter.

On page 206 Scotty raises the very interesting observation that it was hardly mentioned by the great amateur astronomers of the 19th century, even though their telescopes were certainly capable of detecting it.

Your chances of seeing the Veil nebula increase dramatically as the aperture of your telescope increases, but you can get very good results using an 8 or 10 inch telescope and a OIII filter. To see the individual strands with the structure a medium power should be selected (80x or 100x works well). Filters can work with smaller telescopes too, provided the magnification is not pushed too high. Below is a sketch I made a few years back of the eastern Veil using my 80mm f/5 achromat at 20x,with a 1.25″ OIII filter attached.

NGC 6992/95 as sketched with a 80mm f/5 refractor, x 20 & OIII filter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Though he doesn’t mention them much, Houston describes his 5 inch binoculars on page 208. Earlier in the text, he does say that they were hobbled together from two Apogee 5 inch x 20 richfield refractors:

My Japanese 5 inch binoculars, though very heavy, originally had only a shaky tripod. I remounted them on a 3 inch pipe held in concrete down to the bedrock that is Connecticut. A well greased flange allows motion in azimuth while the altitude motion is provided by the binoculars’ built in trunions. Though makeshift, the mounting is granite steady and turns smoothly.

pp 208

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Author’s note: This is ‘vintage’ Scotty; making do with simple, no frills setups to maximise the time spent observing! Inspirational or what!

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On pages 208 through 210, Scotty shifts gear and dicusses the curious case of NGC 6811, a small open cluster located just under 3 degrees northwest of the challenging double star, Delta Cygni. Though his own notes recorded it as rather lacklustre; he received a curious letter from an amateur based in Denmark;

Several years ago I received a letter from Tommy Christensen, who lived in Odensa, Denmark, and observes with a 3.5 inch refractor. Along with a description of M33 and the Veil Nebula was a brief note about the open star cluster NGC 6811 in Cygnus. He called it one of the most beautiful clusters he had seen and mentioned a ‘ dark band about 5’ thick running through the middle of the cluster, not completely without stars, but nevertheless conspicuously dark.”

pp 209.

Scotty solicited comments from his army of fans, deliberately keeping his question about NGC 6811 vague.  Some of the responses he got were hilarious (you can read them for yourself on page 209), but quite a few folk did notice such a dark lane.

His conclusion was right on the money though:

This is a beautiful, albeit minor example of how people see things differently. Everyone was looking at the same cluster, but because of experience, conviction, or psychological factors, each saw it in a different way.

pp 209

The remainder of this chapter covering the September sky is devoted to Aquila, the celestial Eagle. On page 213, Scotty mentions our very own Rob Moseley (who kindly chimed in to this website a while back confirming the prowess of the Orion/Skywatcher 180 Maksutov in regard to its ability to resolve double stars) who wrote Scotty concerning the planetary nebula, NGC 6804;

One of the great pleasures of deep sky observing is the individuality that certain objects acquire in the eyepiece. I’m always delighted to learn that someone sees an object in a new perspective. One such example is Robert Moseley of Coventry, England, who tracked down NGC 6804 while testing a new 10 inch f/6 reflector. His best view was at 120x. He writes,” It gives the impression of a highly condensed but partially resolved cluster. It is a faintish oval nebulosity with a 12th magnitude star near its northeastern edge. With averted vision at least one other star could be seen superimposed upon it.” Moseley questioned the 13th magnitude I had given for NGC 6804 in an earlier column. Published magnitudes for planetary nebulae cause many disagreements, and I believe it is best to slightly mistrust all of them and to record your own magnitude estimates with your notes.

pp 213.

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Author’s note: Well done Rob! A fine addition to a fine book!

I like Scotty’s attitude to estimating magnitudes. What’s all the fuss about?

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Chapter 10: October

October is a most auspicious month for amateur astronomers. The summer haze and humidity have given way to cooler days and crisp, clear skies at night. darkness comes earlier, dewing of the telescope’s optics is generally less of a problem, and the sky is not do jammed with star clouds that confusion rules.

The Milky Way stretches from east to west across the northern star patterns, but here we are looking in the direction approximately away from the center of the galaxy. Star swarms marking the galaxy’s plane are thinner, and it is easy to star hop and make finder searches for objects embedded within them. Some of the most beautiful sights for small telescopes are in and around this corner of the Milky Way.

pp 217

October is indeed a wonderful month to be out of doors. The leaves of decidous trees shut down their chlorophyll factories, revealing the aureal tints of their secondary pigments. Nights are pleasantly long and temperatures remain mild for the most part. The great Square of Pegasus and Andromeda, the Chained Lady, loom large nearly overhead, ripe for exploration with binoculars and telescopes. And it is here that Scotty begins his adventures.

Beginning with the Square of Pegasus itself, Scotty asks a simple question requiring nothing from his readers except their naked eyes. How many stars can you count within the confines of the Square?

If you can see 13 you are reaching magnitude six.

pp 218

On the next page he follows this up with another question. How many deep sky objects are visible in Pegasus? The answer to this question depends on how acute your vision is but also on the size of the telescope you observe with. And it is here that Scotty reflects on the growth of telescopic aperture in comparison to earlier times:

Telescopes of 17 inch aperture are now off the shelf items of modest cost. There are a dozen or more amateur groups in the United States that either now have or are completing instruments with apertures of 24 inches or more. Such light gathering power brings within reach of the backyard observer virtually every deep sky object in the NGC and IC compilations. Thus the Great Square of Pegasus alone contains more than 100 suitable objects.

pp 219

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Author’s note: Scotty is referring here to the Dobsonian Revolution that swept the amateur world by storm in the last quarter of the 20th century. The Newtonian reigns supreme! As I explained in my book, Choosing and Using a Dobsonian Telescope, this was a true revolution and the only one that has occurred in amateur astronomy in living memory. And it’s gone from strength to strength; now amateurs are using fast 30 inch + behemoths for very reasonable cash investments, and which breakdown into convenient packages that can fit in an average sized car.

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The first deep sky object visited is 12th magnitude NGC 7479, found by panning just shy of 3 degrees due south of Alpha Pegasi, which marks the southwestern (Scotty mistakenly quotes southeastern pp 219) corner of the square;

The magnificent barred spiral galaxy, NGC 7479 in Pegasus. Image credit: ESA/NASA

If your eye is properly dark adapted, the galaxy should be visible in even a 3 inch telescope, but a 6 inch is better. A cloth over your head and the eyepiece gives you good protection from stray light. I have seen it easily with my 4 inch Clark refractor, but with small an instrument it is not possible to see any detail. On the otherhand the 12 inch f/17 Porter turret telescope at Stellafane in Springfield, Vermont, offers a more interesting view. At 300x the central bar is obvious and there is a hint of a spiral arm at one end.

pp 219/20

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Author’s note: My 8 inch reflector at 60x can make out the galaxy’s bright core, but the spiral arms do not yield at any power. Caldwell 44 needs a big gun to do it justice!

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Time and time again, Scotty affirms that high f ratio ‘scopes appear to do better than those of low f ratio, but is careful not to jump to any firm conclusions;

A 12 inch f/5 reflector set up near the Porter telescope did not offer as good a view of NGC 7479 even though I thought the mirror was good.It may have something to do with the longer focal length of the Porter telescope, or a better eyepiece. The importance of fine quality eyepieces has been overlooked by many amateurs…..Objects once considered only within reach of large amateur instruments are being seen in smaller telescopes equipped with fine eyepieces.

pp 220

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Author’s note: This is a can of worms! Don’t go there Scotty!

Longer focal length mirrors have less geometrical aberrations than their shorter focal length counterparts. That’s why we have coma correctors, for example! The former also hold their collimation better. That’s one of the principal reasons why I have called for the introduction of a mass market 8 or 10 inch f/7 Newtonian. Eyepiece quality is important too, as Houston points out. But we live in wonderful times nowadays. Eyepieces of higher quality than arguably the best in Scotty’s day are now available at very reasonable prices.

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On pages 222 through 226, Scotty sojourns to two celebrated globular clusters adorning the autumn sky; Messier 15 in Pegasus and Messier 2 down in Aquarius.

Messier 15 as imaged by the Hubble Space Telescope. Image credit: Wiki Commons.

M 15 is easy to find about 4 degrees northwest of Epsilon Pegasi. At magnitude 6.3 it’s just within the visual range, provided you have keen eyesight and observe under a dark, country sky. The finder view is very distinctive, as the globular sits a mere half a Moon diameter due west of the magnitude 6.1 star. It pays to study the field at low power. Both objects are of the 6th magnitude but that of the globular is integrated, while that of the star is a point source. This is a good place to learn the difference between the two concepts.

The view of M15 is impressive with anything from binoculars to the largest telescope. telescopes of 4 inch aperture and lesswill not resolve the core of M15. My 4 inch Clark refractor at 40x shows M15 as a slightly oval disk, more luminous in the center, with edges just beginning to break up into individual stars. Increasing the magnification enhances the view, and at 200x stars at the center of the cluster star to be resolved.

pp 223.

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Author’s note: M15 is a beautiful object at 150x in my 8 inch f/6 reflector. If you have a telescope of 12 inches or larger, M15 presents an extra challenge for you. Located in the northeast corner of the cluster is the 14th magnitude planetary nebula, Pease 1 (mentioned by Scotty on page 224). This was the first planetary to be found within a globular cluster. It was discovered in 1928 by Dr. Francis Gladheim using the 100 inch Hooker reflector atop Mount Wilson.

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Moving to the northern edge of Aquarius, the Water Bearer. You can track this magnitude 6.6 globular a little over 4 degrees north of Beta Aquarii. My 130mm f/5 reflector at 100x shows it be noticeably elliptical and more condensed than M 15 but still a fine sight nonetheless. Scotty writes some interesting notes on M2:

The famous variable starobserver and comet discoverer Leslie Peltier finds M2 a more difficult object for the unaided eye than M33, the large spiral galaxy in Triangulum. In the clear dark skies over the Yucatan peninsula in Central America I could view M33 directly, but M2 required averated vision before it could be glimpsed directly. But I have seen M2 often with the naked eye in Kansas, Missouri, Arizona, and even from the bayous of Louisiana. Binoculars give enough detail to keep the amateur interested, while the view I once had with the Wesleyan University’s 20 inch Clark refractor was spellbinding.

pp 225

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Author’s note: I would agree with Scotty that you’ll need a good 12 inch (see page 226) or larger telescope and high magnification to fully resolve this globular cluster

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As a child  I would stand outside on autumn evenings and fantasize about constellations. I would watch as the horse archer Sagittarius shot a golden arrow at Scutum( Sobieski’s Shield). The arrow would strike the top of the shiled, tearing a great hole in it, and the fragments would fall back together as the arrow shaped open cluster M1.  The arrow would then soar upward into the star clouds, where it would hang poised for another  target in the Milky Way or perhaps another galaxy or even some imaginary other universe.

pp 226

With beguiling prose like this, Scotty would set his readers reeling for crystal clear skies. This is how he introduces his next object, the globular cluster, M71 in the peitite constellation of Sagitta, the Celestial Arrow, easily found immediately north of Aquila. Scotty says he first spied this 8th magnitude cluster with his 40x spyglass of 1 inch aperture. You can pick M71 fairly easily as it lies about midway between the third magnitude luminaries, Delta and Gamma Sagittae.

My 130mm f/5 reflector at 123x shows up a suprising number of stars (about two dozen) in this globular in a pretty stellar hinterland. Indeed, one can be fooled into thinking M71 is a dense open cluster rather than a bona fide globular. Scotty provides us with these notes;

My old 10 inch f/8.6 reflector, which, with its 0.75 inch thick plate glass mirror, was essentially a forerunner of today’s Dobsonians, gave a magnificent view of M71 at 100x. Stars were visible across the entire disk, and the object looked decidely like  an open clusterThe 20 inch Clark at Wesleyan University’s Van Vleck Observatory in Connecticut shows something  more globular.

pp 228

On pages 230 though 232 Houston discusses the celebrated Helix Nebula (NGC 7293) in Aquarius. In his discourse, Scotty includes the descriptions provided by dozens of observers using all manner of telescopic aids and is well worth a read.

On page 234, Twinky discloses a wonderful snippet of American astronomical history:

After the U.S. Civil War, however, Americans went on an observatory building binge. Funding for many installions came from state legislatures, since the astronomers provided time signals to their local areas. Almost every observatory from that era had a transit instrument for determining time. In return for their service, the lawmakers funded a large telescope to keep the astronomers happy. When I was at the University of Wisconsin in the 1930s, Wasburn Observatory still had the big brass fittings on the control board that routed time signals to commercial customers…. Most American observatories did not have special programs to search for deep sky objects.

pp 234

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Author’s note: As explained in my book, Choosing and Using a Refracting Telescope, the largest equatorially mounted telescope in the United States in 1830 was a 5 inch Dollond refractor. Henry Fitz  is reputed to have made about half of all the telescopes sold in America between 1840 and 1855. Soon other makers of renown were establishing themselves, including  Alvan Clark & Sons and John Brashear, who improved and continued this telescope making legacy for the next 80 years or so. The great classical refractors, erected in their ‘cathedrals’ dedicated to the heavens, were symbolic of the new scientific confidence that the United States would enjoy well into the 20th century.

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The final pages of this month’s chapter (236 through 238) discuss a number of deep sky objects south of Fomalhaut, many of which were discovered by Sir John Herschel from his observing station at the Cape of Good Hope, South Arica.

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Chapter 11: November

We’re now approaching the end of the observer’s year but that certainly doesn’t mean there will be any let up in the convoy of celestial treasures to be enjoyed. In many ways, Scotty leaves the best until last, exploring as he does the bountiful constellations of Cassiopeia, and Andromeda riding high in November skies, as well as venturing to more southerly destinations in Pisces and Sculptor.

Scotty gets us off to a flying start by exploring a number of beautiful open clusters in Cassiopeia, the Celestial Queen, including NGC 457, NGC 436 and the visually striking NGC 7789.

The beautiful and exceedingly rich open cluster, NGC 7789, in Cassiopeia. Image credit: Hew Holooks.

 

 

 

 

 

 

 

 

 

 

 

No treatise on deep sky observing could fail to ignore NGC 7789, found about halfway between Rho and Sigma Cassiopeiae. Discovered by Caroline Herschel back in 1783, my 130mm f/5 reflector frames the cluster beautifully at 85x, revealing at least three score stars spalshed across an area roughly one quarter the size of the full Moon, and the 8 inch pulls in more than 100 at moderate powers! Scotty doesn’t hold back describing the splendour of this rich galactic cluster 6,000 light years away from the solar system;

NGC 7789 is one of those rare objects that is impressive in any size instrument. With a 4 inch rich field telescope the cluster appears  as a soft glow nearly 0.5 degrees across and speckled with tiny, often elusive, individual stars. the 12 inch f/17 Porter turret telescope at Stellafane picks up more than 100 stars. Through a 16 inch aperture the view is spectacular, and the whole field is scattered with diamond dust. And a 22 inch Dobsonian reflector in the clear skies of california gave a most impressive view with countless sparkling points filling an entire 60x field. I particularly like the drawing made by [Admiral W.H] Smyth with a 6 inch refractor.

pp 243

Another object of note in these pages is M 52. To find this 7th magnitude cluster, consider an imaginary line running from Shedir to Caph. Now extend this line about the same distance again until your finder picks up a roughly kidney shaped foggy patch of light a little less than half the size of the full Moon in diameter.

M52 ; a fine open cluster for small telescopes in Cassiopeia. Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

November is a great month for observing the Andromeda Galaxy (M31), easily found with the naked eye from a fairly dark site a few degrees about Mirach (Beta Andromedae).  Large binoculars can often provide the best views of this enormous spiral galaxy on our doorstep but I am also very pleased with the view served up by my 80mm f/5 refractor coupled to a 32mm Plossl delivering 13x. It shows a very bright nucleus which gradually fades on either side. Just how far one can trace the spiral arms of M31 depends on a number of factors, not least of which is telescopic aperture, visual acuity, sky darkness and transparency. Most backyard ‘scopes can trace them to maybe 3 degrees from end to end, but Scotty informs his readers on page 246 that George P. Bond, employing the 15 inch refractor at Harvard College Observatory was able to follow the spiral arms out to 4 degrees as far back as 1847. Yet, in 1953, Robert Jonckheere, using ordinary 50mm binoculars measured their visble length to be 5.17 angular degrees!  Scotty recommends moving the nucleus out of the field to have the best chance of tracing these spiral arms. Indeed, he claims that after using 15 x 75 binoculars, he was able to measure a length of 5 degrees from end to end!

The great Spiral Galaxy in Andromeda seen here with its bright satellite galaxies, M32 left and M110 ( below to the right of centre). Image credit: Torben Hansen.

 

 

 

 

 

 

 

 

 

 

 

The two bright satellite galaxies attend M31, both of which are easily discerned in my 80mm refractor at the lowest power. M32 lies closer to the core of M31, whilst M110 is located further away ‘below’ the disc of M31. Scotty also reminds his readers that two other companion galaxies can be ferreted out some 7 degrees north of M31; NGC 147 and NGC 185. NGC 147 (actually located over the border in Cassiopeia)., which shines with an integrated magnitude of 9.5 can be found just under 2 angular degrees west of Omicron Cassiopeiae. The other galaxy, NGC 185, is slightly brighter, owing to its smaller, more compact size. It lies just one degree east of NGC 147. Both are well framed in my 8 inch reflector at 30x.

Scotty then moves down to Pisces, to visit the grand face on spiral galaxy, M 74. This magnitude 9.2 gem is easily located in my 80mm refractor by centering the 3rd magnitude Eta Piscium in a low power field. The galaxy is then seen as a ‘fuzzy star’ about 1.3 degrees off to the east and slightly to the north of Eta. You need a larger telescope to make out the spiral nature of this galaxy though. My 8 inch at 150x shows a number of faint stars splashed around its periphery and with good transparency, you’ll be able to make out something of its spiral nature but not a great deal. In general, it’s best to use the largest telescope available to engage in this kind of work.

After discussing some less well known faint fuzzies in Pisces, Scotty finally moves into Sculptor, featuring some of the observations of Ron Morales, Barbara Wilson and Steve Coe.

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Chapter 12: December

The stuff dreams are made of; the Pleiades Cluster in Taurus, with its associated nebulosity. Image credit; Wiki Commons.

December brings winter, and with it many cold but often clear nights. On such evenings, when the stars sparkle like diamonds, there is no sight as spectacular as M45, the Pleiades. Currently, this open star cluster rides high in the eastern sky at the end of astronomical twilight. It is delightful in any instrument, from the naked eye to the largest amateur instrument, although I find large binoculars give the most impressive view. Almost every culture, past and present, mentions in its folklore the dazzling stars in this nearby culture. They have enhanced the imaginations of gifted poet and commoner alike as far as we can remember. They are the starry seven of Keats, the fireflies tangled in a silver braid of Tennyson, the fire god’s flame of the old Hindus, and the ceremonial razor of old Japan. No other celestial configuration appears so often on the pages of the poet.

pp 261.

There can be few sights that move the human spirit more deeply than the sight of the Seven Sisters rising serenely in a dark country sky. The cruelty of winter frost temporarily abates, as the mind soars. Why is the night sky so beautiful? Why were the stars made? Different people have different answers to these questions but to me they plainly attest to a Creator who delights in fashioning beautiful things, and was gracious enough to place them in the firmament so that we might know something of His awesome power. Rich or poor, young or old, the Pleiades is for everyone.

Not surprisngly, Scotty has a lot to say about this magnificent star cluster. How many stars can you see within its confines? Most have no trouble making out six members. With a little practice, a seventh can be made out, but the keenest eyes report more, many more.

Depending on light pollution and sky conditions , most persons can see between four and six naked eye Pleiads.Traditionally, the average eye can see six stars here, the exceptional eye seven, and 10 bear names or Flamsteed numbers. However, during the 1800s the noted British amateurs Richard Carrington and William Denning both counted 14 stars. The late dean of visual observers, Leslie Peltier, told me he could always see 12 to 14 stars on any good moonless night.

pp 263.

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Author’s note: Having average eyesight, I can usually only count 6 members, but have certainly glimpsed a seventh but only in the darkest skies that Scotland can offer. If you have a good, blackened telescope tube (without its lenses) lying about, try peering through it to minimise the amount of peripheral light entering your eye. Can you see any more? Indeed, in perusing the work of the Victorian populariser of astronomy, Sir Robert Ball, I recall him stating that one could see stars during broad daylight if one were to observe from the bottom of a deep well. Alas, I can’t confirm this! 19th century skies were considerably darker than those we typically enjoy today, helping to explain why these observers of old saw so many more Pleiads than we generally can.

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On page 263 through 265, Houston discusses the nebulosity enveloping M45, itself a good sign that the cluster is relatively young ( of the order of a few tens of millions of years most likely). The area of sky around  the star Merope is usually the place where most amateurs report such nebulosity. Technically this is a reflection nebula, where the star light is insufficiently energetic to ionize the gas but enough to allow it to get scattered off innumerable dust grains within the cluster. It was first reported by the German amateur astronomer, Wilhelm Tempel, back in 1859 using a 4 inch Steinheil refractor whilst working in Italy. Scotty points out that seeing this nebulosity depends strongly on the conditions of the sky through which we observe;

From Tucson my 4 inch showed it readily. In Connecticut, a 10 inch reflector failed but in Vermont a 5 inch Moonwatch Apogee telescope succeeded. At the August convention of the Astronomical League in Tennessee, I was surprised to find several observers who had seen the Merope Nebula more than once. It was readily visible in a 6 inch reflector made by Fred Lossing of Ottawa. Once its position southwest of the star Merope was pointed out, others saw the dim glow too. In the 16 inch, the nebula seemed much more obvious, and averted vision was not required.

pp 263.

The Crab Nebula (M1) in Taurus. Image credit: Wiki Commons.

Of course, the Pleiades is grand star cluster within the larger constellation of Taurus, the Bull, and on page 265 Scotty discusses a few other gems that are visible within the constellation using the naked eye, binoculars or a modest telescope. The Hyades is a sight to behold with the naked eye or through low power binoculars or even opera glasses. Then there is the Crab Nebula (M1), which is best found by centering the star Zeta Tauri in the low power field of view of your telescope and then panning 1 degree to the northeast. The Crab is rather disappointing telescopically as it certainly does not resemble the images seen in long exposure photographs, and increasing aperture doesn’t greatly transform the view. Scotty agrees:

The Crab can be seen in 2 inch finders. Small telescopes reveal only a shapeless 8th magnitude blur variously sketched as oval, rectangular, or more often something in between.

pp 268

After discussing a few deep sky objects in Cetus, Scotty throws caution to the wind and encourages sky gazers to return to the easy objects that delighted us in our youth:

As many of us know, the telescope is a wondrous invention, and the heavens contain all manner of marvels that can still astound the imaginative mind, no matter what the smog density may be. Some of the better sights await us in the December evening sky. The Northern Cross is erect in the Northwest; Albireo has already set. Pegasus is now a great diamond shape sloping slowly to the west, as Orion mounts closer to the meridian. This is no time for routine or difficult objects; it is better that we sweep again the old favorites of our youth; the sights that enthralled us with our first homemade reflector.

pp 276

By now, old Twinky was already thinking about the great sights that he would revisit in the new year; the Great Nebula in Orion, Barnard’s Loop, the magnificent Double Cluster; and so it begins again!

Dr. Neil English’s new book, Tales from the Golden Age of Astronomy will be published in the Spring of 2018.

 

De Fideli.

Tales from the Golden Age: A Short Commentary on Walter Scott Houston’s,”Deep Sky Wonders.”

A Distillation of observing notes from the late Walter Scott Houston(1912–93).

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Between 1946 and 1994, the noted American observer, Walter Scott Houston, wrote the Deep Sky Wonders column for Sky & Telescope magazine, entertaining several generations of amateur astronomers across the English speaking world. His great personal knowledge of the deep sky and enthusiasm to share his experiences were downright infectious. With beautiful prose and just the right amount of technical detail, Houston’s writings presented delightful ‘word pictures’ of the many deep sky objects that adorn the night sky. The present work, first published in 1999 by Sky Publishing Corporation, represents a distillation of his writings which appeared a few short years after his untimely passing in December 1993.

The copy of the book discussed here refers to the paperback edition (309 pages), containing a preface, followed by 12 chapters covering all the months of the year, and ending with source references, a bibliography and index. The selective writings are edited by the noted observer and former Sky & Telescope columnist, Stephen James O’ Meara.

The Preface

This is divided into three distinct sections with commentaries from O’ Meara, Brian Skiff and Dennis di Cicco, who provide interesting biographical details of Houston’s life and observing philosophy.

Born in Tippecanoe, Wisconsin, on May 30 1912, Houston developed an early interest in optical instruments, constructing his first telescope as a preteenage boy: a 1 inch aperture refractor from salvaged spectacle lenses, and mounted inside a cardboard tube, which provided a magnification of 40 diameters. But we also learn that ‘Scotty’ was far more knowledgeable about microscopes than telescopes. Growing up in an era where good telescopes were very expensive by modern standards, Houston, like so many of his contemporaries, resorted to grinding his own mirrors in order to sate his growing aperture fever. This resulted, we are further informed, in a badly made 6 inch primary mirror he finished in 1930, but it was soon improved upon when he apparently produced a first rate 10 inch silver on glass mirror which formed the heart of Houston’s first serious telescope, an instrument that consolidated his lifelong love for the treasures of the deep sky. The interested reader will note that Scotty’s 10 inch mirror is on display at the R.W. Porter Museum of Amateur Telescope Making, Springfield, Vermont.

After leaving school, Scotty studied for a degree in English literature at the University of Wisconsin and it was here that he made his acquaintance with a one Joseph Meek, who stoked his interest in observing variable stars. Indeed, after joining the American Association of Variable Star Observers (AAVSO) in 1931, he went on to contribute an astonishing 12,500 observations throughout his long life!

Scotty was quite the scholar, securing teaching positions at various public schools and universities across the American Midwest. During World War II, he served as an instructor for pilots at the Army Air Force’s Navigation School, at Selman, Louisiana. Finally, he moved to Connecticut, where his skills in the written word were put to good use as an editor for American Education Publications, a post he held until his retirement in 1974. He and his wife, Miriam, were inveterate travellers, visiting astronomical conventions and star parties across the United States, where he endeared himself to the community, which had so admired his Deep Sky Wonders column over the years and decades since its inception back in 1946.

Observations made with this homemade 10 inch f/8.6 reflector formed much of the basis of Scotty’s earliest astronomical forays, conducted under the dark skies of rural Kansas throughout the 1950s. That instrument must have been a best of a ‘scope, but it served as his workhorse for many years. Scotty was also very enthusiastic about using binoculars, as we shall discover. His association with the AAVSO introduced Houston to arguably his favourite telescope;a 4 inch f/15 Clark achromatic refractor. On page 84 of Deborah Warner’s book, Alvan Clark & Sons, Artists in Optics, we learn of more details about the instrument:

William Tyler Olcott, the author of several popular books on astronomy, used a 4 inch aperture Clark refractor made in 1893. A wooden tripod supported the brass with nickel tube and a hand driven work wheel. Olcott later gave the telescope to Phoebe Haas (q.v), who then gave it to the American Association of Variable Star Observers, which in turn loans it to its members. The Olcott instrument is now being used by Walter Scott Houston.

pp 84.

A neoclassical 4 inch f/15 refractor, similar to that used by Houston, and once used by this author for several years.

Later in his life, Houston acquired a 5 inch Apogee ‘Moonwatch’ rich field refractor delivering a fixed power of 20x, which he used to sweep the skies, and which features in many of his later monthly columns. He also had in his possession a 5 inch binocular, which is occasionally mentioned in the text.

Scotty eschewed the growing number of amateur astronomers who were becoming increasingly obsessed with their equipment. He was an observer, not a ‘gear head’. Brian Skiff explains:

Scotty had a light touch and avoided being distracted by technical details. You don’t find any invidious comparisons of different telescope or eyepiece brands in his writing or much about the nitty gritty of equipment at all, because Scotty knew that the most important piece of equipment was the eye, and its training the most important activity; all else was trivial in comparison. Time wasted arguing the virtues of one eyepiece over another was time not spent honing your observing skills.

xiv

How times have changed!

It was with this modest cache of instruments that Walter Scott Houston created his literary magic; word enchancements that we shall explore in this essay.

Houston invited many of his readers to comment on the more speculative commentaries he made in the course of making his observations, and accordingly invited them to write him with their findings. In this way, Houston built up a formidable correspondence base with fellow observers across the United States, Canada and further afield, and when he attended star parties he would get to finally meet his admirers in person. Back in those days before internet, Scotty corresponded with his fans via snail mail. Specifically, they’d receive a small blue postcard with a personalised message. In these and other ways, he endeared himself to his readers and inspired many to take up the gauntlet to explore the riches of the deep sky.

One of his greatest admirers was W. H. Levy, of comet fame. Indeed, according to Skiff, it was ‘Twinky’ (aka Houston), who provided the essential push to him becoming the celebrated comet discoverer he subsequently became:

David Levy tells the story of meeting Scotty at a Deep Sky Wonder Night in northern Vermont in late August 1966. He had just begun comet hunting some months earlier. In the middle of the night, David took a break and began telling Scotty of his hopes to discover a comet someday. Puffing slowly on his pipe, Scotty asked David what the sky was like outside. He answered that it was pretty clear, dark and moonless. Scotty then asked if David’s telescope was out there, to which the answer was “yes.” Scotty took another puff on his pipe, looked up quizzically and said, “Well, David, you sure aren’t going to find a comet as long as we’re inside talking about it!”

xiv

In 1980, Scotty underwent surgery to remove a cataract from his observing eye. As we shall see in his discourses, this greatly increased his sensitivity to shorter visual wavelengths as well as ultraviolet radiation. We will also discover a wealth of information concerning what ordinary individuals achieved using modest instruments, thereby providing yet more historically relevant documentation on what experienced individuals saw under the starry heavens. The individual chapters cover the entire observer’s year, parsing the sky up into twelve slices, with each fully two hours of right ascension in width. So, why not pull up a chair and enjoy some of the highlights of this charming and inspirational work from memory lane.

The Great Nebula in Orion, the majestic furnace of winter. Image credit Wiki Commons.

Chapter 1: January

I learned my constellations in Tippecanoe, Wisconsin, a town that long ago vanished into the urban sprawl of Milwaukee. Back then Tippecanoe was a rather treeless tract of farmland bounded by the great clay buffs of western Lake Michigan. The sky ran right down to the horizon, with an almost irresistible force, called for you to look at it. In January 1926, after a midnight walk home from ice skating, I wrote:

Snow crystals like blue diamonds, but with a dreamy gentle radiance totally unlike the harsh gem. A rail fence as black as Pluto himself runs along the road. The forest is black in the distance. The landscape is a masterpiece in ultramarine and sable.

As if in contrast, the heavens above blaze with a thousand tints. Incomparable Orion leads the hosts with blue Rigel, ruby Betelgeuse, and bright Bellatrix. His silver belt and sword flash like burnished stellar steel. And more advanced is the dark and somber Aldebaran, so heavy and gloomy. In fitting contrast are the delicate Pleiades, who sparkle “like a swarm of fireflies tangled in a silver braid.”

How can a person ever forget the scene, the glory of a thousand stars in a thousand hues, the radiant heavens and the peaceful Earth? There is nothing else like it. It may well be beauty in its purest form.

pp 1/2

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Author’s note:  Few books make an entrance like Scotty’s opening lines of chapter 1. Recalling the days of his youth, when the skies near his home were sublimely dark and crystal clear, and when light pollution was simply non existent, Houston thrusts us headlong into the starry universe of a freezing January night. Such a scene reminds this author of the sable skies of his own youth, when he’d sit on his back on a windswept sand dune on the south coast of Ireland during summer holidays, where the stars, too numerous to count, would stretch all the way down to the horizon! The brilliant luminaries of January, coupled to the naturally darker sky experienced as our planet faces away from the hustle and bustle of the down town Milky Way, would have certainly bewitched the young sky gazer and instilled in him/her a great yearning to explore its cavernous reaches with optical aid.

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On page 2 through 5, Scotty introduces us to the glories of the Great Nebula in Orion, a most fitting place to start Deep Sky Wonders. He describes how the nebula was first ‘discovered’ in 1611 and informs us that Sir William Herschel turned his first homemade reflecting telescope toward it in 1774 in the aftermath of some two hundred failed attempts to fashion a decent speculum mirror! Scotty’s mind wanders, as he discusses the drawings made of the Orion Nebula by telescopic observers prior to the advent of astronomical photography;

Drawings of the Orion Nebula made before the influence of photography raise more questions than they answer. Only superficially do the sketches bear any resemblance  to one another. The bright section of the nebula drawn by Bindon Stoney using Lord Rosse’s 3 foot reflector in Ireland doesn’t begin to match what I saw in 1935 with the 36 inch reflector at Steward Observatory in Arizona. Trouvelot’s 1882 lithograph based on observations with the Harvard 15 inch is a reasonable match to my view through a 3 inch. On the other hand, John Mallas’ drawing in the Messier Album, made in the 1960s with a 4 inch telescope shows features that most observers need a 10 inch to see.

pp 4

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Author’s note: It is difficult to see the precise point Scotty is making here. Certainly, the visual acuity of the observer has a role to play, and it is certainly true that a good observer with a small telescope will probably see more than a poor observer using a larger instrument. Nevertheless, it is undoubtedly true that for observing the Orion Nebula (or, indeed, the vast majority deep sky objects) that a good observer will see more in a larger instrument than the same individual will see in a smaller one, provided the optics are working as they ought to.

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The Nebula, as Scotty ably reminds us, responds well to all magnifications. “Its chaotic form gives a strong impression of twisting and turbulent motion,” he writes, “that are too slow to follow….. and its green tint is obvious to most. …… With low powers and a field wide enough to include the whole nebula, it becomes an object compelling enough to draw exclamations of delight from even the most disinterested bystander.”

pp 5.

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Author’s note: Scotty is dead right! Seeing the Orion Nebula through most any telescope, large or small, is sure to knock your socks off and is arguably one of the best outreach objects to enthral beginning observers.

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On pages 5 through 6, Scotty discusses the elusive Barnard’s Loop, an enormous, faint emission nebula running for several tens of degrees east of the Orion’s belt asterism.  He informs us that E.E. Barnard did not, in fact, discover the structure. It was the harvard astronomer, W. H. Pickering who first picked it up on photographic plates made at Mount Wilson in 1889; a full five years before Barnard’s own wide field astrographs confirmed it.

The beautiful but visually challenging Barnard’s Loop in Orion. Image credit: WIki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In all his years of searching with instruments of all shapes and sizes, Houston admits that the structure had eluded him, until one night at his Connecticut home, he saw it with his naked eye when he placed a OIII filter up to his eye! The sighting of it drove him wild:

My wife says I jumped clean over the observatory (it’s a small building).

pp 6

Sticking with elusive objects, Scotty then moves onto the Horsehead Nebula, which, although discovered photographically in 1900, had eluded the most seasoned deep sky observers for generations. It’s found very close to 2nd magnitude star, Alnitak, the southermost luminary in the Hunter’s belt. Even to this day, the Horsehead has evaded most deep sky observers, generally requiring large aperture telescopes and excellent seeing conditions. A Hydrogen beta filter (unavailiable in Scotty’s time) also helps make this nebula pop.

Scotty provides his own findings with the Horsehead:

From Connecticut my 4 inch refractor failed to reveal the Horsehead, but my notebook indicates that it was visible from Kansas with a 10 inch reflector. I have since fished it out using a 4 inch Clark, a 4 inch off axis Newtonian telescope made by Margaret Snow, a 5 inch Moonwatch Apogee telescope under the same circumstances as Mr. Wooten, immediately after the passage of a cold front.Scattered light from 2nd magnitude zeta foils many attempts to find the Horsehead, since the two are seaprated by only 1/2 a degree.

pp 8

Less challenging is the Flame Nebula (IC 434), located a mere 15 arc minutes to the southeast of Alnitak. Scotty reports that the Flame has been observed in instruments as various as a 60mm classic refractor as well as small reflecting telescopes. Scotty received reports that the Flame was exceptionally well observed at high altitude.

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Author’s note: Many years ago, during my brief forays into astrophography, I captured a reasonable image of the Horsehead and Flame Nebula using a 8 inch Schmidt Cassegrain telescope on Kodak ektachrome. Visually, it remains an elusive object to my eyes. The Flame Nebula can be glimpsed at powers of about 200x in a good 8 inch reflector and of course, one should not neglect Alnitak itself, which presents as a wonderful triple star for backyard telescopes.

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Scotty made it very clear from his writings and correspondences with amateurs across the country that the sighting of many deep sky objects depend more on the condition of the sky from which it is observed than the visual acuity of the individual. This is brought into sharp focus whilst discussing his next January target, M33, the Pinwheel Galaxy in Triangulum, which is presented on pages 9 through 11. Good seeing conditions and clean air swept clear of particulates render M 33 visible without optical aid. Scotty also informs us that it can prove a difficult target to pin down telescopically, owing to its low surface brightness:

With a diameter of 1 degree, the 7th magnitude spiral more than fills the field of view in high power binoculars and presents an almost featureless glow that is easily missed. Therefore, very low powers or even small binoculars give the best view.

pp 10.

The Pinwheel Galaxy, as imaged in a 10 inch Newtonian reflector. Image credit: Alexander Meleg.

With careful study in a moderatey large back yard telescope, Scotty  says;

“M 33 is usually smooth, but on one night I saw the whole surface surprisingly mottled, with the southeast part considerably brighter than the northeast….. Most observers settle for for locating NGC 604, a bright knot in one arm 9.1′ east and 7.6′ north of the galaxy’s nucleus….. One night in an 8 inch, a congested mass of bright patches was seen superimposed on an overall spiral pattern.

pp 11

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Author’s note: The Pinwheel is a fascinating object to study in telescopes of 8 inches or larger aperture. It is very well presented in my 8 inch reflector at 30x, where a roughly ‘S’ shaped structure is seen snaking its way from a slightly brighter and more condensed centre. If you crank up the power to over 100x or so, one can make out NGC 604 as a distinct blob at the extreme tip of the galaxy’s northern spiral arm.

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On pages 11 through 15, Scotty fleshes out details of an interesting correspondence with a one Pat Brennan, of Regina, Saskatchewan, an avid deep sky obsever who used a homemade 6 inch f/7 Newtonian to carry out his own observations of more obscure NGC objects and who was struck by the disprepancy between their description in Dreyer’s New General Catalogue (and its revisions) and how he found them at the eyepiece. As Scotty points out, the all sky photographic surveys, recording as they do a bewildering number of faint and bright objects, would often overwhelm well defined clusters as seen in a small amateur telescope. A few such objects (loose open clusters) are discussed, including NGC 1662, NGC 2180 and NGC 2184 in Orion, NGC 2251 in neighbouring Monoceros and NGC 7394 in Lacerta. The moral of the story here is that until one actually observes such systems for oneself, descriptions can be next to meaningless.

The magnificent Double Cluster (Caldwell 14) in Perseus.

 

 

 

 

 

 

 

 

 

On pages 16 through 19, Scotty discusses one the most beautiful deep sky treasures in all the heavens, the celebrated Double Cluster (also known as Xi Persei) in the constellation of Perseus. Although known to the ancients, the Double Cluster’s true majesty could scarcely be revealed until the age of the telescope was upon us. And while anyone evenly briefly acquainted with the night sky can find it without much trouble with the naked eye, Scotty is nonetheless careful to provide his readers with good directions on how to find it from less than ideal skies.

Scotty reveals that many of the great telescopic observers of past centuries recognised its splendour, including W.H. Smyth, T.W Webb and W.T. Olcott. Serviss’ Astronomy with an Opera Glass, published in 1888, described it thus:

With a telescope of medium power, it is one of the most marvelously beautiful objects in the sky; a double swarm of stars, bright enough to be clearly distinguished from one another, and yet so numerous as to to dazzle the eye with their lively beam.

pp18.

A composite drawing of the Double Cluster by the author conducted with a 32mm Plossl coupled to an 18cm f/15 Maksutov Cassegrain.

Houston provides his readers with some historical references to observers who first coined the term ‘Double Cluster’, with a number of individuals using the phrase beginning around the latter part of the 19th century. From here, Scotty wastes no time in providing his impression of the system as seen through a medium sized telescope:

Each of these two open clusters would stand well on their own , but they are even more spectacular because, less than a degree apart, they are visisble in the same low power field. I see h Persei (NGC 869) being slightly brighter and more concentrated of the two. Becvar’s Atalas catalogie gives the star count in NGC 869 as 250. Just 1/2  a degree east, Chi Persei is said to contain some 300 stars. However, anyone who looks with a 10 inch telescope will certainly consider the catalog values to be conservative.

pp 19

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Author’s note: Scotty declares that the finest views he has personally enjoyed of the Double Cluster was with a 6 inch refractor equipped with a special 4 inch focal length ocular designed by Art Leonard. This author has observed these clusters with all manner of instruments, including opera glasses, a three draw spyglass with a one inch diameter objective, binoculars of various sizes, as well as a plethora of astronomical telescopes. Arguably the best view was enjoyed with a rather specialised 8″ f/6 doublet achromat (utterly useless at high power though), but these days he is completely sated with the medium power views served up by his workhorse instrument, a 8″ f/6 Newtonian reflector.

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The final pages of this opening chapter discusses a number of NGC objects in the far southern constellation of Fornax. On page 23, Houston discusses the visibility of the planetary nebula, NGC 1360:

A short notice on this object was in Deep Sky Wonders for 1972, and it surprises me now. I wrote that NGC 1360 was not seen in a 4 inch reffractor but glimpsed with a fast 5 inch refractor; a sad testimony to the murk of my Connecticut skies that evening…

pp 23.

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Author’s note: This is an intriguing statement, and one that flies somewhat in the face of much contemporary ‘wisdom’. Afterall, a quality 4 inch long focus refractor (his beloved Clark) ought to see things ‘better’ than a fast achromat only an inch larger, right? Wrong! Scotty had little reason to prevaricate. The larger instrument showed up this magnitude 9.4 Robin’s Egg Nebula, where the 4 inch apparently could not; and under the same conditions!

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Chapter 2: February

The chapter begins in the rather lacklustre constellation of Camelopardalis, to an oft overlooked galaxy that presents as quite a spectacular sight from a dark sky site; the barred spiral galaxy NGC 2403. Scotty comments that it was,

too bad Messier missed this spiral while hunting comets. If it had been included in his list, it would certainly one of the better known galaxies in the northern sky. Sky catlogue 2000.0 lists NGC 2403 as about 1/4 of a degree and shining with a total light of an 8.4 magnitude star  values similar to famous Whirlpool Galaxy, M51. Indeed, NGC 2403 is the brightest galaxy north of the celestial equator that does not have a Messier number. pp 28

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Author’s note: One can find NGC 2403 about 7.5 degrees northwest of the third magnitude star Omicron Ursae Majoris (Muscida). My observations indicate that it is somewhat larger than Scotty’s quoted size; more like 25 x 13 arc minutes and thus covering an area roughly half that of the full Moon.

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NGC 2403 featuring supernova 2004DJ as imaged by Rochus Hess using a 25cm f/5 Newtonian astrograph.

As Houston rightly points out, this remarkable non Messier object is well seen in large binoculars and is a ” lovely gem” in his 4 inch Clark refractor. He also points out that the famous American comet hunter, Leslie C. Peltier, included NGC 2403 in his list of galaxies used for testing out the suitability of a telescope for comet hunting. Through his 10 inch reflector the view was transformed into “an ocean of turbulence and detail.” This is more like the description this author recognises in his 8 inch f/6 Newtonian at powers of 100x or so.

Scotty then goes on to describe another galaxy in the celestial Giraffe; IC 342, first discovered by the great English amateur astronomer, W.F. Denning in the 1890s. Houston quotes this galaxy as a 12th magnitude spiral galaxy and is very much more faint than NGC 2403. Scotty was unsure about whether it constituted a bona fide member of the Local Group. Today, we know for sure that it is. This author has not seen this faint galaxy personally, but it shouldn’t present as too much of a difficulty in an 8 or 10 inch telescope with averted vision and low powers.

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Author’s note: The integrated magnitude of IC342 is quoted as between 8.4 and 9.1 depending on the source; both of which are considerably brighter than the magnitude 12 figure quoted by Scotty on page 29.

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Intriguingly, Scotty mentions that despite several attempts to see IC 342 with a number of 4 inch refractors, he never managed to see it with such instruments, but does go on to say that, “using a 10 inch reflector I noted it as easy and even stands 100x once located.

I wonder what you see?

Kemble’s Cascade. Image Credit: Wayne Young.

On page 30, Scotty presents his wonderful word painting of one of the most striking asterisms in the entire heavens; Kemble’s Cascade:

Despite more than half a century of peering into nooks and crannies and looking where the guide books were silent, I missed one of the sky’s more beautiful asterisms. In 1980 a letter from Lucian J. Kembe, who lives under the clean skies of Alberta, Canada, told of a fine grouping he had come across.While sweeping  with 7 x 35 binoculars in Camelopardalis, kemble found a “beautiful cascade of faint stars  tumbling  from the northwest  down to the open cluster NGC 1502.” I called the asterism Kemble’s Cascade when writing about it in this column. The name has stuck.

pp 30

It was Houston who honoured Fr. Kemble with this discovery; a remarkable feat in itself as was apparently unnoticed by earlier observers. Kemble’s Casacade runs for about 2.5 degrees all the way from Cassiopiea right down to the open cluster NGC 1502 in the Camelopardalis. My 80mm f/5 achromatic refractor frames the entire line of some 15 stars (the brightest of which is magnitude 5) using a 32 mm Plossl delivering 13x. The magnitude 5.7 cluster, NGC 1502 is also worth scrutinising with binoculars or a small telescope, where some four dozen members can be made out with a concentated gaze.

Gaius; the author’s 80mm f/5 refractor.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Scotty also points out that the cluster is home to two interesting multiple star systems for small telescopes; Struve 484 and 485. The former is a pretty communion of three suns, with the two fainter members separated from the primary by 5.5″ and 22.5″. The latter is a wonderful amalgam of nine suns, seven of which have magnitudes in the range  7 to 13th magnitude and according to Scotty are, “within reach of a good 4 inch telescope” pp 31. The remaining two members, he says, are within range of a 8 inch telescope.

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Author’s note: I can confirm that a good 8 inch reflector can tease all of the Struve 485 members fully apart and is quite a sight for sore eyes, as one might imagine.

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During the early 1980s, new filter technologies were coming to the fore that would soon render objects previously considered all but invisible plainly seen. This would come about with the invention of broadband and narrow band filters and it is noteworthy that Scotty lived during this era;

At the 1982 Texas Star Party, I was asked what was the best new challenging deep sky object after the large aperture Dobsonian revolution had dispatched most of the test objects from the 1950s and ’60s. I suggested the california Nebula, not knowing that a piece of modern technology would soon remove it from the the list of challenges; a skyglow piercing nebula filter. In fact, I remember saying that it is the ultimate test object for visual observers. So much for that wisdom, for little did I realize when I made the comment that before I returned to Connecticut I would see the nebula with my naked eye through an O III filter. In the winter of 1992, in Mexico, the same filter showed the California nebula as bright.

pp 34.

Scotty informs us that this extraordinarily elusive object (prosaically referred to as NGC 1499) in Perseus was discovered visually by the young E.E.Barnard in 1885 using the 6 inch Clark refractor at Vanderbilt University, Nashville, Tennessee. Barnard is well known for possessing incredibly acute vision, especially for faint objects on the precipice of vision. On page 35, Scotty offers his regal advice to observers wishing to see this object;

A low magnification should be used so that the field of view shows plenty of sky to contrast with the object. the telescope’s optics should be well collimated and free from dust and dirt that would scatter light and reduce the image contrast. The eyepiece also should be clean , and all air to glass surfaces antireflection coated. While a number of things affect the visibility of Low Surface Brightness (LSB) objects. I suspect that seeing them depends more on observer experience and eye training than on specific telescope f/ratios and magnifications.

pp 35

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Author’s note: From a dark sky, away from the artificial lights of towns and cities, cast your gaze immediately north of xi Persei. NGC 1499 spans a whopping four full Moon diameters (two angular degrees) in extent. If you can’t spot it with the naked eye, try holding up a Hydrogen beta filter (which transmits at 486.1nm), which should greatly help in the visual discernment of this emission nebula. A regular Deep Sky filter should also help. The hydrogen gas that constitutes the bulk of the nebula is excited by  xi Persei, which is itself a member of the Perseus OB2 association of hot, young stars. Telescopically, one ought to choose a small rich field telescope offering as wide a field as possible, and again, one should couple this to an appropriate filter. Good luck in your endeavours to see this amazing structure!

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Page 35 recounts a number of ways amateurs have seen the California Nebula over the years. Perhaps the most endearing is that described by a one Alister Ling from Montreal, Canada, who wrote Scotty with this tale. He was visiting his friend, David H. Levy, and took a small boat out upon a lake near his cottage where the air was exceptionally tranquil (think Big Bear Solar Observatory):

I made a monocular from my 400mm telephoto lens by attaching a 28mm orthoscopic eyepiece to it. This gives a magnification of about 14x and a field several degrees in diameter. No sooner had I located xi Persei than the extended nebula was quite obvious. It was about 1.5 degrees long with two fairly bright stars embedded near its edge. Roughly near its midpoint there is an obvious kink in the nebulosity. It appears more like a mass of unresloved stars than a gas cloud; very much as the Milky way appears to the naked eye. Later, a crescent Moon rose in Gemini, and rendered the California Nebula invisible.”

pp 35

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Author’s note: Those were the days eh! Fun with a makeshift telescope! I can’t imagine many folk doing something like that now. Note also how the nebulosity completely vanishes in moonlight!

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In the clear, cold nights of winter, the dazzling constellation Perseus stretches its silvery fishhook high in the northern sky. The Milky Way narrows considerably in Perseus, being partly veiled by interstellar dust, and we are looking well away from the center of the galaxy, in Sagittarius. Star charts show that the open star clusters which abound in Cassiopeia and Auriga are noticeably fewer in Perseus. But the constellation does offer many objects that will reward the observer who braves the cold weather to observe them.

pp 36

With words such as these, how could anyone resist the opportunity to venture outside on a clear winter’s night to observe the glory of the firmament? Scotty understood that the stars offered a kind of comfort that could not be found elsewhere. He was drawn to them, like a duck to water.

We move from Perseus briefly to explore a splendid telescopic object; M27 (NGC 6853), the Little Dumbbell, in the diminutive constellation of Vulpecula, the Fox, at the head of Cygnus. One of the brightest of the planetary nebulae, it is easily seen in binoculars as a 8th magnitude misty glow. Scotty says it’s hard to find though, and he’s right! Thankfully, he offers the reader an easy way to locate it;

Start with Phi Persei. This star and a dimmer one just to the south from a pointer, with Phi at the head that directs the observer to a diamond of faint stars, within which M76 is dimly perceptible.

pp 36.

The Little Dumbbell (M76) in Vulpecula. Image credit: Robert J. Vanderbai.

A telescope transforms the binocular view immeasurably. In my old 4 inch f/15 achromat, it appeared as a roughly boxed shaped object, greenish in hue, and about twice as long as it is wide. It responds well to high magnification. 200x is the order of the day. Two lobes of this planetary nebula are seen projecting out at either end with a pretty smattering of faint stars strewn across its face. Scotty decribes it thus:

With a small aperture or in indifferent sky conditions, M76 shows only a dim irregular oval with ragged edges. But one night, with an 8 inch reflector in the hills of the Golden Gate in san Francisco, M76 was a most exciting object.It appeared more than 2′ by 1′( large for a planetary) and high magnifications brought out an intricate network of tubulent celestial clouds.At Stellafane in Springfield, Vermont, M76 appeared as a marvelous object in George Scotten’s 12 inch f/5.7 Dobsonian reflector. The nebula seemed to float between us and the starry background, its edges appearing  even more faryed than when smaller telescopes are used. Its curled twists and streamers seemed to show the whole mass in turmoil. At the 1992 Winter Star Party in the Florida Keys I had a chnace to view M76 through a 36 inch Dobsonian reflector built by Tom and Jeannie Clark. To reach the eyepiece required climbing a stepladder half as high as the surrounding palm trees, but the view was worth it. it made anything I had ever seen in my old 10 inch reflector just a dusty memory.

pp 37.

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Author’s note: Scotty vividly describes what amateur astronomers refer to as ‘aperture fever.’ That said, though he most certainly enjoyed and appreciated the views through giant light buckets, there is no evidence that he ever personally succumbed to them. Evidently, he was completely sated by much smaller, simpler kit.

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From Vulpecula, we venture back into Perseus once more, where Scotty discusses the bright open cluster M 34. Situated about half way between Algol (the Demon star) and the famous double star, Gamma Andromedae (Almach), this magnitude 5.2 open cluster is an excellent target for binoculars or a small telescope.Scotty was of the opinion that the best views of this cluster were to be had with 15 x 65 binoculars, although I think the view is equally compelling at 13x in my 80mm f/5 refractor. A 4 inch telescope shows up a few dozen stars loosely associated with each other and varying in brightness from the 8th to the 12th magnitude.

Many observers, including Scotty, have noted additional structures inside the cluster more reminscent of that seen in globulars than any other type of object. Scotty also mentions the interesting double star at its heart.

I see three noteworthy curved rays of stars running out from the center which are very  evident in my 4 inch Clark refractor at 40x. Indeed, they even show in binoculars. Near the center of the swarm  lies the double star Otto Struve 44, which my 4 inch refractor splits nicely at 100x, especially when the heater is turned on to remove any trace of dew  from the objective. The primary star is of magnitude 8.5 and 9.2 companion is 1.4″ distant at position 55 degrees(toward the northeast)

pp 39

One of the great charms of reading the work of historical figures is the thrill of discovering new information about how our hobby has changed over the years and, just as importantly, how it has not changed! Such knowledge is valuable. On page 40, Houston says that until the 1970s, most deep sky charts never listed objects fainter than about 13th magnitude. The reason he says is because truly big telescope mirrors were hard to come by because they rapidly became too heavy and unwieldy. Back then, mirrors were made with a diameter to mirror thickness ratio of 6:1. A 6 inch mirror was already one inch thick and a 12 inch would have to be 2 inches thick!  And those big mirrors didn’t come cheap either:

Such mirrors larger than 12 inches cost a fortune.

pp 40

And yet, Scotty was an accomplished ATMer:

In 1932 I made a 10 inch reflector from 1/2 inch plate glass. The mirror had to be carefully supported or else it made every star in the field appear double; pretty but hardly suitable for astronomy.

pp 40

Indeed, Scotty goes on to say that during the early 1930s, the largest telescope dedicated to serious amateur observing was a 13 inch reflector donated by Cornell University to the Milwaukee Astronomical Society.

By the 1980s, advances in manufacturing technology ensured that virtually any good sized star party across the United States had good telescope mirrors 20 inches or larger in size, allowing the 13th magnitude barrier to be broken. As a test for this 13th magnitude + limit, Scotty offers the galaxy trio, NGC 1130 (magnitude 13.0) and NGC 1129(+14.5) and finally NGC 1131 (+15.5). According to Scotty, these should all be visible in a good, modern 10 inch reflector from a suitably dark site.

The remainder of the chapter discusses the huge and winding constellation of Eridanus, the celestial River. Alas, owing to my own far northerly location (56 degrees) only the northernmost tip of this constellation (to the southwest of Orion), is on view and thus I’m not in a position to comment on many of the objects Scotty discusses here, which are better suited to those observing at more southerly latitudes.

As darkness settles on the February landscape, the mighty Hunter Orion stands high over the southern horizon. Now is a fine time, however, for observers living in northern temperate latitudes to explore the backwaters and eddies of the the River Eridanus cascading westward from brilliant, blue white Rigel. Eridanus meanders in graceful loops and bends before disappearing below the southern horizon, where it ends at Achernar deep in the southern sky at declination –57 degrees.

pp 42.

The majestic barred spiral galaxy, NGC 1300 in Eridanus. Image credit: Hubb;e Site Images

Scotty goes on to inform us that Eridanus offers no star clusters to the observer but does have a profusion of galaxies. One good target for small telescopes is NGC 1300, a rather fetching barred spiral galaxy, with a visual magnitude of 10.3. Houston says:

It is within reach of a 4 inch, and I have seen it easily with a 3.5 inch Questar telescope.Though photographs  of NGC 1300 with larger telescopes reveal a central bar with two thin but tightly wound spiral arms, smaller amateur instruments show only a blurred spindle. A 4 inch f/12 oof axis reflector suggested some detail in the glow but fell short of showing any spiral structure. A 10 inch or larger will give a more diatinct image, about 6′ x 3,’ and may even reveal the faint companion to the north, NGC 1297.

pp 43.

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Author’s note: This is arguably one of the most accessible galaxies in Eridanus even for those living at high northern latitudes. You can find it by panning about 2.3 degrees north of third magnitude Tau Eridani. An 8 inch or larger reflector and power of about 200x gives quite a good view of its main features.

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In discussing NGC 1232, found just 3 degrees southwest of NGC 1300, Scotty mentions something curious;

In my 4 inch refractor it seems to be better seen with a 150x eyepiece than with a 50x used in combination with a 3x Barlow lens. This is curious, for usually a Barlow and a long focus eyepiece give a view a view superior to an eyepiece of shorter focus that is used alone.

pp 44.

What do you think?

On page 45, Scotty commences a fascinating discussion on the ‘natural tools’ deep sky observers employ in order to see faint objects on the edge of visibility. In particular, he mentions averted vision, long known to experienced observers, but stresses that it is not equally effective for all observers. Some folk get more out of it than others, as it were.

And, like any other human endeavour, visual astronomy is not an exact science. There are exceptions to every rule:

In experiments at the Naval Research Laboratory in the late 1950s, one subject actually saw less as the image approached the edge of his retina. However, one exceptional individual’s sensitivity increased steadily in both colors; the gain in red light was three magnitudes in a direction 40 degrees from the fovea. These experiments, by J.L. Boardman, were done with scotopic(dark adapted) vision……. Until the tyro observer acquires the skills needed to ferret out fainter deep sky targets, there is often a period of frustration at the eyepiece.

pp 45.

The moral of the story here is that no book or instruction manual can ever reveal the optimum method of visualing faint fuzzies. Personal experimentation is the only sure way of getting ahead.

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Chapter 3: March

Walter Scott Houston was the complete observer. He was as happy looking with his naked eye, as he was with the help of various optical accoutrements, particularly binoculars and telescopes. Curiosity drove him.

It is in this vein that Scotty opens his topics for discussion for the month of March, and in partcular, to a beautiful, though quite elusive object in the wilds of Monoceros.

On a trip to a high altitude site in Northern Mexico he recalls:

The first target was an old favorite of mine, the Rosette Nebula( NGC 2237–39) to the east of Orion in the stellar wilderness we call Monoceros. Without a filter only a tiny glimmer of light was visible, but with an ultrahigh constrast (UHC) filter the nebula burst forth in specatcular fashion. I know of no other object in the sky where flicking back and forth in front of a naked eye produces such a wonderful effect.

pp 49

It is true indeed true that the Rosette Nebula, or that “elusive wreath of winter”, as Scotty referred to it, is often better seen in a finder ‘scope than the main instrument. Binoculars allow one to easily centre the open cluster embdeed at the epicentre of this highly complex structure; NGC 2244 easily found about two fifths of the way between ruddy Betelgeuse and brilliant white Procyon. My 80mm f/5 achromatic telescope shows up about two dozen stellar members at 50x, but larger telescopes show even more stars in the hinterland. Finding the surrounding nebulosity, of course, is an entirely different matter. Its fairly low altitude in my winter sky renders it exceptionally challenging and I’ve only glimpsed the brightest (western) edge at low power in the same telescope in the wee small hours of the morning (when the glow from Glasgow, 25 miles to the south is minimised, or ‘Glasglow’ as I disaffectionately refer to it), after a cold front has swept the air clean of particulates. Inserting a nebular filter (and powers below 50x or so) to dim the stars of NGC 2244, immeasurably improves the visibilty of the brightest parts of the associated nebulosity.

Imagers have revealed the Rosette to be enormous in relative terms; fully 1.3 square angular degrees in extent. And what a photographic spellbinder it is too!

The beautiful Rosette Nebula in Monoceros, as imaged by Andreas Fink using an 8 inch f/4 GSO imaging Newtonian.

 

 

 

 

 

 

 

 

From page 49 through 52, Scotty launches into a wonderful discussion about the Rosette Nebula, detailing how this object was discovered piecemeal. Sir William Herschel, for example, discovered the open cluster NGC 2244 but entirely missed the nebula. Neither was it seen my Charles Messier or Admiral W. H. Smyth. William Lassell however, observing with his splendid 48 inch speculum reflector from the pristine, dark skies of Malta in the 1860s, described the same cluster with the nebulosity!  And while seeing parts of the emission nebula once took on the mantle of a test object, the arrival of modern nebular filters have long removed that distinguished status from it.

From Monoceros, we move northward into the constellation of Gemini, the Heavenly Twins, where Scotty waxes lyrical about arguably one the finest Messier Objects in the northern sky; the enormous, tumbling chaos that is M35:

M35 is my favorite open cluster. Located about 2.5 degrees northwest eastward of Eta Geminorum, it is an an impressive frame of bright stars with a softly flaming background of fainter ones, seemingly containing hundreds of members. William Herschel did not include the cluster in his general catalog of deep sky objects. It was his way of honoring Messier as the man who, through his earlier catalog of about a hundred deep sky objects, had inspired him to conduct his own sky survey.

pp 52

I agree wholeheartedly with Scotty in considering M 35 to be the most visually stunning open cluster in the starry heaven. It has the uncanny ability to induce gasps of delight each time I run my telescope through this region, situated at the northern foot of the constellation.

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Author’s note: Eta Geminorum (Propus) mentioned in passing by Houston is also a most challenging binary star, consisting of a marmalde orange giant star (possibly variable owing to its advanced age, and first noted as such by Julius Schmidt back in 1865) with a much fainter bluish companion that is seen to ‘bleed’ from the primary under high magnifications. Very tough for a 4 inch telescope, this author has enjoyed his finest display of the rather elusive secondary using a 8 inch f/6 Newtonian on the frosty evening of December 12 2015. See here for details.

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M 35 (lower right) as imaged by the 2MASS all sky survey.  Note also the fainter cluster NGC 2158 just off centre right. Image credit: Wiki Commons.

M35 is so large that its glory is often lost in rather small, restricted fields of view offered up by large telescopes. Yet, every increment beyond binoculars causes M35 to increase in majesty. My 80mm achromatic telescope shows it well, but the view is greatly improved in my 5.1 inch f/5 reflector at 20x. But it is with my largest telescope, an 8 inch f/6 reflector, equipped with a 40mm wide angle eyepiece delivering 30x, that I drank up my finest views of the system in recent years. Scotty seems to have enjoyed a somewhat similar viewing experience to my own;

To me, M35 seems most lovely in a 6 inch at 40x; though I must admit that, through a 36 inch telescope and a wide field eyepiece, this blaze of interwoven stars is an awe inspiring sight. But I have probably viewed M35 the most with my homemade 10 inch reflector. This was my workhorse telescope years ago on Louisiana and Kansas. Wide field eyepieces were rare during the 1940s and ’50s so, using a pair of achromats and fooling with the spacing between them, I made a wide field eyepiece with passable quality. It was a copy of what 19th century photographers called a landscape lens, and it wasn’t far removed from the design now commonly called a Plossl. ….With this eyepiece on the 10 inch I could get all of M35 into a single field. The view was too beautiful to describe with mere words. Bright stars were scattered with cosmic recklessness across the field, and it was difficult to establish where the cluster’s edges dissolved into the stellar background.

pp 54.

After enjoying the sheer magnificence of M35 through the telescope you’d be forgiven to have totally overlooked the fainter open cluster located a mere 0.4 degrees to the southwest of it. But once you ‘discover’ this other system, NGC 2158, it’s like the icing on the cake. Doubtless, were it located in some other, less extraordinary patch of sky,  this rich but faint open cluster would be more often cited by deep sky observers. It is thus easy to see why, historically, it was all but overlooked by early telescopists. NGC 2158 is poorly rendered in my 80mm f/5 refractor but is quite prominently displayed in my 5.1 and 8 inch reflectors at low and moderate powers.Here’s Scotty’s description of the cluster;

The dim, arrow shaped cluster lies right on the outer edge of M35 and is a pitfall awaiting careless observers. In my youth NGC 2158 escaped my attention until one exceptional night. From the 1920s on I had looked at M35 many times, mostly with 4 and 6 inch telescopes, but occasionally with the Milwaukee Astronomical Society’s 13 inch reflector. Then while observing with a 10 inch f/8.6 reflector in 1952 under the excellent skies of Manhattan, Kansas, I accidently discovered a peculiar wedge shaped object. For a few heartbeats I thought I had discovered a comet! Fortunately, before announcing my “comet” to the world, I checked the Skalnate Pleso Atlas Catalogue and found that it was the small star cluster NGC 2158.

pp 55.

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Author’s note: Scotty’s ‘discovery’ of the ‘comet’ near M35 is par for the course for any experienced deep sky observer. And while NGC 2158 seems for all the world like it is physically associated with M35, it actually lies some 10,000 light years farther away than its more illustrious neighbour!

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Pages 57 through 62 are devoted to two rather special ‘deep sky’ objects, multiple stars to be more precise; Castor( Alpha Geminorum) and Sirius (Alpha Canis Majoris). Scotty recounts his own personal history with both systems, how their brighter companions have changed their orbital distances and position relative to their primaries over the decades and centuries, as well as some of the historical personae associated with them. Castor presented Scotty with one of his earliest visual feats; resolving it into two components in the 1920s using a “1 inch homemade refractor.”

Sirius B, first seen by accident by Alvan G. Clark in January 1862, whilst testing a new 18.5 achromatic doublet objective for Dearborn Observatory, Illinois, was actually deduced to exist some 18 years before it was observed by the German astronomer, Friedrich W. Bessel (not mentioned in the text by Scotty). The system also caught Scotty’s attention as a young man, where he managed to split the pair with a truly famous instrument:

I first split the pair in 1932 with the same 6 inch Clark refractor used earlier by the famous double star observer Sherburne W. Burnham.

pp 61.

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Author’s note: Wow! What an honour that must have been! S.W. Burnham was a gifted (and entirely self taught) double star obsever. He saw things that still stretch credulity!

The brighter companions to Castor (B &C) and Sirius B can currently be enjoyed in very modest backyard ‘scopes. A 3 inch refractor and moderate powers ought to easily bag both.

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And it was Burnham’s equally famous colleague and friend, E.E. Barnard, who, Scotty reliably informs us, discovered a whopping five new nebulae within one angular degree of brilliant Castor in 1888!

NGC 2410 lies 1 degree north of the star, whilst the others ( IC 2194, IC 2193, IC 2199 and IC 2196) lie even closer in, off to the southwest of Castor. All are in the 14th and 15th magnitude range.pp 61.

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Author’s note: I have never searched for, yet alone seen any of these objects, but they’d make an interesting project for a dark, moonless, winter’s evening in a moderately large telescope.

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Appropriately enough, Scotty dedicates the next couple of pages of the book to another Messier showpiece, M41, located just 4 degrees south of the Dog Star. As always, delightful words stream from Scotty’s thought flow:

In contrast to Sirius, the field below is dark and vacant, allowing the eye to regain some of its sensitivity. After a minute or two this mighty galactic cluster rides into view. Its stars shine with  the total light of single 4.5 magnitude sun, which puts the cluster well within range of the naked eye. It would probably be better known as a naked eye target were it not so low in the sky as seen from northern temperate latitudes.

pp 63

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Author’s note: From my far northerly latitude M41 is always very low when it transits the meridian, making it a considerably more difficult object to see visually (though it certainly can be seen!). A good binocular object, my 5.1 inch reflector at 60x shows the system well, revealing about three dozen stars spread over an area slightly larger than the full Moon, though I suspect that were it higher in the sky I might be able to divine still more members.

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Messier 41 in Canis Major as imaged by NASA’s 2MASS survey. Image credit: Wikicommons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Scotty also mentions two faint open clusters discovered by Clyde W. Tombaugh (about whom this author will have much more to say in an up and coming chapter) located about four degrees east of M41 (pp 63 to 64).

Did you know that the month of March offers up more 1st magnitude stars than any other from northern latitudes? Trust Scotty to notice and with great literary poise:

During March evenings eight 1st magnitude stars sit in solemn conclave in the sky above my Connecticut home. Two are in Orion, while the others are arranged in orderly grandeur around the great Hunter. Three naked eye star clusters; the Pleiades, Hyades and Praesepe; are strung along the ecliptic carrying with them a wealth of ancient folklore. Near the meridian beams the Great Orion Nebula, also visible to the naked eye. Galactic clusters are legion in the winter Milky Way, and overhead Capella shepherds a profusion of them in Auriga.

pp 65.

You can tell where Scotty is going to venture next; that splendid trio of open star clusters in the celestial Charioteer: M36, M37 and M38, as well as a few other systems of lesser splendour.

The stellar storm that is M37. Image credit: NOAO.

Scotty says M37 is the prettiest of these, and I would agree. It’s easy to find a little southeast of the midpoint between Theta Aurigae (itself a good double star for small telescopes) and Beta Tauri. First described by Hodierna back in 1654, it was independently discovered by Messier over a century later. My 80mm f/5 glass shows up a respectable 50 or so members at 50x. There’s also very pretty 9th magnitude orange star marking its epicentre, which only adds to the great natural beauty of the system.

Here’s how Scotty describes M38:

Moving “down” the Milky Way, we run into such variegated sar fields and clusters that it almost impossible to know where to halt, but this might very well be at M38. Although this cluster is well within the star strewn, it is usually visible to the naked eye without much effort.It is certainly far easier than M33(the Triangulum Galaxy), and probably easier than M11, the Scutum cluster. Evenly compressed into a glowing ball two thirds the diameter of the full Moon are over a 100 softly blazing suns. M38 is a magnificent in any sized instrument.

pp 66

Houston then calls our attention to paths less travelled, beginning with the magnitude 7.5 open cluster, NGC 1893, located just 3 degrees west of M 38. My 8 inch reflector at 100x unveils about four dozen stars arranged in a wedge shape some 12′ in size. The cluster is enveloped in a cocoon of gas and dust, IC 410, a sure indicator of its very young age (of the order of a few million years). This creates the somewhat hazy appearance of the cluster as seen in small telescopes, but Scotty raises some interesting questions all the same:

In small apertures the cluster does show a haze of unresolved stars, but, as mentioned, NGC 1893 is involved with the nebula IC 410. Like many observers, I have looked at the cluster but not seen the nebula. Could the glow we attribute to stars just below our telescope’s limit really be due to the nebula? Has anyone examined this group with a nebula filter? The results might be startling.

pp 66

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Author’s note: You can indeed see traces of the IC 140 nebulosity by employing an OIII filter coupled to a moderately large aperture ‘scope. My 8 inch reflector shows up the most prominent whisps toward its northwestern edge, but a 12 inch will transform the view into something quite spectacular. NGC 1893 is an active region of star formation.

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Scotty discusses other, less well celebrated open clusters in Auriga on pages 67 through 68 for those who enjoy a faint fuzzy challenge. In the remaining pages of this chapter, he covers a few objects of note in the southerly constellations of Columba and Lepus.

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Chapter 4: April

This chapter opens with a discussion of the novel constellation of Lynx, introduced by Hevelius in the 17th century to fill the space between the cluster rich constellation of Auriga ad the galaxy rich Ursa Major. Scotty’s first target is NGC 2419, found by panning your telescope about 7 degrees north of Castor. Shining at magnitude 10.3, this globular cluster is of particular interest owing to its great distance from the solar system; 330,000 light years, by the best estaimtes. That places it about twice as far from us as either of the Magellanic Clouds.  Yet, all the while, though its remoteness is truly mind boggling, NGC 2419 is well seen in a small telescope;

Despite its great distance, NGC 2419 shines at about 10th magnitude and appears a little less than 2′ across. Under good observing conditions the cluster should be visible with a 3 inch telescope. I once saw it from Kansas with a 4 inch refractor stopped to 2 inches and 100x. The cluster should always be within reach of a 6 inch glass, and a 12 inch may start to show some hint of individual stars around the edge. It is a beautiful object for a 17 inch. More distant globular clusters have been discovered on photographs made with the 48 inch Schmidt telescope on Palomar Mountain. However it is unlikely that any would be within the visual reach of amateur astronomers.

pp 77

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Author’s note: Scotty, like virtually all of his contemporaries, thought that NGC 2419 was a true intergalactic ‘interloper’ unhinged from the gravitational influence of the Milky Way but the latest research suggests it is indeed bound up with our galaxy taking approximately 3 billion years to complete one orbit.

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Scotty concedes that while Lynx is home to about a dozen galaxies, most are very faint. The exception he says is NGC 2683, which is an unexpectedly bright spiral galaxy (magnitude 9.8). Scotty accurately describes it as “cigar shaped” about 3 times as long as it is wide. While discussing this, he brings up some interesting points about the merits of having a stable mount and the relative efficacy of ‘sweeping’ as opposed to studying a ‘steady’ view:

In general, a loss of 1.5 or 2 magnitudes occurs when a rigid stand is not used.I was amazed at how much better my 20 poer Apogee telescope performed after a solid support was made for it.  Experienced observers know that bright objects can be seen during a sweep, while those near the telescope’s magnitude limit require the field of view to be steady. It helps to know exactly where to look. In this way I was able to locate NGC 2683 with a 3 inch aperture at 60x……..yet it is an easy object in a 4 inch telescope on just about any night.

pp 77.

NGC 2683, a magnificent spiral galaxy in Lynx and easily in reach of small backyard ‘scopes. Image credit: Wiki Commons.

Author’s note:  NGC 2683 can be a spectacular object in a large telescope. Arguably the best view I have personally enjoyed was with a 12 inch Dob at 150x, where I was able to see clear signs of mottling. The northwestern edge of the galaxy is also seen to extend further from the core than its southwestern counterpart.

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Scotty briefly discusses several other moderately bright galaxies in Lynx, including magnitude 10.9 NGC 2859 just west of Alpha Lyncis, followed by NGC 2500, NGC 2782 and  NGC 2844 (see pages 78 and 79). From here, Scotty turns his attention to one of the finest galactic sights visible in the northern sky, the ‘dynamic duo,’ M81 and M82, which are exceptionally well placed high in the sky on April evenings.

Both M81 and M82 are easily found about 2 degrees east southeast of the 4th magnitude star, 24 Ursae Majoris. Visible in a 50mm finder from a dark sky site, the view improves with every increment in aperture. Morphologically though, they could hardly be more different.;

While M81 is a textbook example of a spiral galaxy, its companion, M82, is anything but. It is in fact, one of the most unusual galaxies within the range of small telescopes.At magnitude 8.4, it is also within the grasp of binoculars.

pp 81

M81 ( bottom) and M82 (top) ; a sketch made by the author using his 80mm f/5 achromatic refractor on the evening of March 14 2015.

 

Scotty draws our attention to a number of less celebrated galaxies within easy reach of this pretty galaxy pair. Indeed, they are all part of the so called M81 galaxy group, including the magnitude 10.2  NGC 2976, which is well seen in my 8 inch reflector at 150x. You can find it just 1.4 degrees south southwest of M81. Scotty says he got a good view of this galaxy with a 2.4 inch (60mm) classic Unitron refractor.pp 81.

On pages 82 to 83, Scotty embarks on another discussion about some interesting double stars, in particular, Beta Delphini, which he says, “never gets more than 0.7″ apart.” What comes next is fascinating:

Typical is the report of Charles Cyrus of Baltimore, Maryland, whose 12.5 inch f/7.2 reflector has no clock drive. At 572x he saw the components clearly separated.

pp 82

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Author’s note: Scotty is a breath of fresh air! Here is yet another account of a reflecting telescope splitting sub arc second pairs! And Mr.Cyrus evidently didn’t even use a clock drive! This is in perfect agreement with my work with two reflectors; a 130mm f/5 and a 204mm f/6; both of which have been shown to be excellent double star instruments.

The interested reader will also find some tips on page 83 on how best to tease apart the closer pairs with various telescope types.

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On pages 84 through 87, Scotty discusses one of the finest and accessible open clusters in the northern heavens; the famous Beehive Cluster (M44) and its interesting hinterland. Spanning a region of sky fully 1.5 degrees wide, M44 is a mesmerizing sight in a small, richfield telescope at low power. You can find it by pointing your telecope to a spot midway between Castor & Pollux in Gemini and Regulus in Leo.

My 130mm f/5 reflector presents the entire star cluster beautifully at 20x and, unlike many other deep sky objects, it closely resembles the nickname bestowed upon it.

The celebrated Beehive Cluster (Praesepe) in cancer. Image credit: Miguel Garcia.

Here’s how Scotty describes the Beehive:

In low power fields, finders and binoculars, M44 is a brilliant show object. It has no sharp boundary. No one can say for sure where the cluster’s faint glow merges into the placcid sjy background. And the center is hardly brighter than the edge.The cluster appears as a ghostly sheen of cobwebs at least a degree in diameter, sometimes maybe two. Through a large telescope, the view is not particularly impressive, because the stars are widely scattered. But the cluster is an exciting object for binoculars and rich field telescopes. the best instrument for viewing M44 is one that has a field of at least 1.5 degrees across with the largest aperture that will still give an exit pupil no more than 7mm in diameter. I had an excellent view of an object with my 4 inch Clark refractor and a special eyepiece of 4 inch focal length designed by Arthur Leonard.

pp 86 to 87

For the remainder of the chapter Scotty calls our attention to various deep sky objects in Hydra, which snakes its way below the ecliptic, from Cancer in the west to Libra in the east.

In the introduction to this section, we gain valuable information concerning the origin of the Messier Marathon:

The idea of a Messier marathon; an all night session to view as many of the Messier objects as possible; sprung up independently in several locations. According to Harvard Pennington, president of California’s Pomona Valley Amateur Astronomers (PVAA), the first marathon dates to the late 1960s and a group of observers in Spain. On this side of the Atlantic, it was the mid 1970s before amateurs in Florida and Pennsylvania took up the challenge. Unaware of the earlier efforts, California comet hunter Don Macholz suggested a Messier marathon in an article published in the San Jose Amateur Astronomer’s newsletter in 1978.Pennington claims that the cat got out of the bag when I wrote about the Florida and Pennsylvania projects in my March 1979 column. After that, marathons became inceasingly popular.

pp 89.

Perhaps the most celebrated Messier object in Hydra is M48, found by moving your telescopic eye about 3 degrees south southeast of 4th magnitude Zeta Monocerotis. Binoculars reveal a few dozen members with a somehat triangular shape, and with a steady hand and my 130mm f/5 Newtonian and low power shows up at least 70 members arranged loosely over a field just shy of one angular degree. What ever item of equipment you have, M48 is well worth a gander under a dark sky.

Scotty offers some interesting background information concerning this beautiful open cluster:

The open cluster M48 was long believed to be a “missing” object until Harvard astronomer Owen Gingerich linked it with NGC 2548, which Caroline Herschel discovered in 1783. If Gingerich is correct, the original published position for M48 was about 5 degrees in error. Seemingly Messier made a mistake of 5 degrees in declination, but his right ascension is correct. But this identification seems pretty certain since there is no other nearby candidate matching Messier’s visual description of M48.

pp 90

Over the next few pages Scotty deals with a number of fainter objects in Hydra, as well as the far southerly spiral galaxy, M83.

The wonderful Planetary nebula in Hydra, NGC 3242. Image Credit Wiki Commons.

As previously mentioned, Houston underwent cataract surgery on his right eye in the summer of 1980. Many of his fans became concerned that he might give up observing all together, but their fears were soon allayed when he declared that it actually gave him a new lease of life! In particular, because a cataract selectively absorbs shorter wavelengths of visual light over longer ones, it can induce a colour bias to the objects one sees through the telecope. Scotty disclosed how his new, artificial lens perceived the bright planetary nebula, NGC 3242:

Ron Morales found NGC 3242 easily with a 6 inch f/5 telescope at 50x. Recently I looked at it with my 5 inch Apogee telescope and a 20x eyepiece. It appeared slightly oval but without the pointed ends so prominent in photographs of the object. The central star was easily seen with my eye that had its lens removed during cataract surgery. The star appeared almost as bright as the entire planetary in this eye, while it was hardly visible at all in my normal eye. This was surely due to a greater amount of ultraviolet (UV) light reaching the retina of the eye without its natural lens. Central stars in planetaries are generally strong emitters of UV.

pp 95.

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Author’s note: Scotty reminds us all that growing old need not inevitably lead to reduced observing activity. His artificial lens allowed him to see objects in new ways, enhancing rather than hindering his enjoyment of all things astronomical. I wonder whether he also saw that little bit more chromatic aberration through his beloved Clark achromat?

Younger individuals usually report a bluish tinge to planetary nebulae, becoming more green as one matures in age, but there are always exceptions.

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Chapter 5: May

The magnificent Omega Centauri. Image credit: ESO.

When the jet stream bulges soutward, it allows Canadian air to pour across the United States and cover all but the far West with a stable mass of cold dry air.Amateur astronomers benefit with dark nights of crystalline transparency and better astronomical seeing. Under these conditions it is no problem viewing 5th magnitude stars only 1 degree above the horizon. Globular cluster fans should wait for that special evening to try for Omega Centauri, the finest of all globulars. The search must be done when the cluster is at its highest point in the sky. On May evenings the cluster lies near the meridian. It culminates at the same time as Spica; just look for the cluster 36 degrees below the star.

pp 99.

Shortly before his death in 1993, Twinky ventured south to the Florida Keys to make his maiden observation of Omega Centauri, the finest globular cluster in all the heavens. In many ways, seeing this outstanding natural beauty was the icing on the cake for this humble man who truly loved the heavens.

Unfortunately, owing to its extreme southerly latitude, it never rises anywhere near the horizon from my far northern latitude. But it is one object that I long to see. Those lucky enough to have seen it inform me that with a telescope of 8 inches aperture about 1,000 stars can be made out at high power. And with larger telescopes, red supergiant stars can be distinguished within its seething mass.Of course, one doesn’t have to travel below the equator to see this wonder of the heavens, as Scotty explains:

In theory, an observer in the Northern Hemisphere can see into southern declinations as far as the corresponding colatitude(down to 90 minus the latitude of your location). From geometry alone we can calculate that Omega Centauri should be visible from as far north as 42.5 degrees north latitude. In practice that value is too small, because atmospheric refraction at the horizon lifts starlight by 0.5 degrees, so Omega might be viewed from 43 degrees. The challenge is to see it through terribly dense and contaminated air. Ordinarily horizon mists, smoke, and dust take a good 10 or 15 degrees off this figure.

pp 101.

What follows is a fascinating discourse on what a number of amateurs have experienced while observing Omega with various telescopes.

Progressing further through the May chapter, Scotty returns to more familiar territories, partcularly the subject of galaxy visibility. On page 103 through 105, he describes an interesting experiment carried out by a few enthusiastic amateurs concerning the factors that affect the visibility of faint galaxies in Leo Minor, specifically NGC 3414, NGC 3504 and NGC 3486, all of which hover around the 11th to 12th magnitude. The results, unsurprisingly, were far from clear cut, involving aperture, magnification and interpersonal variation.

Scotty learned from experience that two eyes are better than one:

Lately I have become increasingly aware that more can be seen with two eyes than with only one (Microscopists have known this for centuries).

pp 103

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Author’s note:

The author’s fine old binocular compound microscope by Vickers (formerly Thomas Cooke & Sons, York, England)

Although I certainly appreciate the value of two eyes when using a microscope, I have still to explore fully the advantages of binoviewing in astronomy. Unfortunately, though my (limited) experiences of using them have been exercises in frustration more than anything else, I don’t doubt that they would enhance my observing experience. Binoviewers are on my future ‘to buy’ list.

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On page 105 through 106, Scotty, now entering the 1990s, reminisces about how the world of astronomy has changed from the time he was young.

As we begin the last decade of the 20th century, I’m flooded with the realization of how much astronomy has changed in my own lifetime and how rapidly it continues to change. In the 1930s I remember when the first photoelectric measurements of starlight were made using an electronic amplifier. Back then we only dreamed of space rockets. But today those rockets loft telescopes into space with detectors thousands of times more sophisticated than that crude photometer of the 1930s……Amateurs work very differently now than they did only a few decades ago. For example, in the early years of deep sky observing  I would set up a small refractor near my home in Milwaukee’s Bay View. With a copy of Norton’s Star Atlas in hand (the only deep sky reference commonly available  at that time), I would sweep the sky. Today’s beginners are likely to have an 8 inch or larger telescope and access to detailed charts showing hordes of galaxies.

pp 105/6

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Author’s note: Times have certainly changed, and for the better. Indeed, amateur astronomers have never had it so good! High quality items are now available at very reasonable prices, allowing most anyone with a modest income to enjoy the night sky. Other things have deteriorated though; light pollution, for example. Many amateurs(perhaps the vast majority) live in cities, where the glory of the night sky is a mere shadow of its true self. Amateurs are forced to travel further and further to seek out truly dark sanctuaries.

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The next target on Scotty’s list is Leo I; a 10th magnitude dwarf galaxy in the constellation of the Lion. It’s very easy to locate, yet quite a challenge to see details in! Locate 1st magnitude Regulus in a medium to high power eyepiece and cast your gaze just 20 arc minutes north of it. If your sky is good and dark, you’ll spot a ghostly glow roughly 10′ in size. Now move Regulus just outside the field in order to increase the contrast with the background sky. Quite a challenge, undoubtedly, but worth chasing up in a moderately sized backyard ‘scope.

On pages 108 through 114, Houston discusses that happy hunting ground for galaxy observers spread across the face of Leo. Scotty provides a sense of the scale of this richness for the reader:

While the deep sky objects in Leo might seem a little drab compared with the brilliant star clusters scattered across the Winter Milky Way, there are some remarkable sights here for 8 inch and larger telescopes. Burnham’s Celestial Handbook lists over 70 deep sky objects in Leo. All are galaxies from the 9th to the 13th magnitude. I wouldn’t even try to guess the number a 17 inch telescope could find. Within the boundaries of the constellation there is not one open or globular cluster or planetary nebula suitable for amateur telescopes. This is interesting because Leo is the 12th largest constellation, covering just under 947 square degrees of sky.

pp 108

The amateur equipped with a modest telescope will thoroughly enjoy these pages on the galaxies of Leo and Leo Minor, as Scotty’s expertise walks you through them. You can enjoy many of these deep sky objects with a small telescope, as he exemplifies. Indeed, some of these galaxies don’t look all that better even when a very large telescope is employed to study them. For example, concerning NGC 3245, Scotty has this to say:

The galaxy is not difficult in my 4 inch Clark refractor at 100x. I once viewed it with a 20 inch Clark refractor at Wesleyan University, and, while it appeared larger and brighter than in the smaller telescope, I did not notice much additional detail.

pp 116.

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Author’s note: Fishing out faint galaxies takes patience. A good dark sky is a huge bonus. Once you see one, the eye has the uncanny ability to pick out several others in rapid succession.

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The last few pages of this chapter are dedicated to one of the sky’s brightest galaxies; NGC 3115 in Sextans. More famously known as the Spindle Galaxy, this bright lenticular galaxy can be tracked down a little over 3 degrees east of 5th magnitude star, Gamma Sextantis. Scotty prefers to let the sky do the work;

Select an eyepiece which shows at least a Moon’s diameter of sky, and place the 5th magnitude Gamma Sextantis near the southern edge of the field. If you leave the telescope stationary for 12 and a quarter minutes(turn the drive off if the telescope has one), the galaxy will be centered near the northern half of the eyepiece field.

pp 120

Houston seems well smitten with this galaxy, referring to it as a “splendid” sight in his small telescopes(pp 120). Indeed, he reckons it looked pretty much the same in his 5 inch Apogee telescope as it did in a 12 inch instrument!

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Author’s note: In my 5.1 inch reflector at 100x, NGC 3115 is clearly tear shaped, about four times as long as it’s wide. My 8 inch Dob shows just a little more detail, with a highly condensed core and a slightly fainter outer ‘halo’. All in all, a marvellous Island Universe to track down and observe on a dark and moonless Spring evening.

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Chapter 6: June

One of the nicest pieces of celestial real estate for hunting down cosmic treasures is the area around the Bowl of the Big Dipper. Aside perhaps from Orion, the Big Dipper is the sky’s best known objects. And what a wonderful selection of objects there is, for it is here in the polar region that the great stream of galaxies reaching northward from Virgo and Coma comes to a brilliant conclusion. Severla bright galaxies from the Messier catalog bedeck the Dipper amind scores of others that are easy targets for 6 inch telescopes.

pp 123/4

With these beautiful words, Walter Scott Houston opens his June chapter, turning his attention to the famous asterism of the Big Dipper, which is better known in Europe as the Plough. And rightly so, for this ‘flower basket,’ as Scotty refers to it, dominates the sky near the zenith during June evenings and thus is very well placed for exploration with binoculars or a backyard telescope.

The first object he addresses is M97 (a.k.a the Owl Nebula), one of the faintest in Messier’s famous catalogue. From my northerly vantage, June is arguably the worst month to see this object, as our skies are filled with seasonal twilight at this time. Nonetheless, you can find this planetary nebula just less than 2.5 degrees southeast of Beta Ursae Majoris(Merak). Scotty says it can be picked off in 15 x 65 binoculars and is easily visible in a 4 inch telecope. The Owl responds well to increases in telesope aperture. My 8 inch reflector coupled to an OIII filter at 120x reveals a colourless, rotund object some one tenth the diameter of the full Moon. A little scrutiny will show the nebula’s two ‘eyes’ staring back at you. Seeing the central white dwarf star is another matter though. While some astronomers claim it can be seen in apertures upwards of 16 inch, I have never laid eyes on it with a telescope of this size.

The Owl Nebula ( M 97). Image credit: Wiki Commons.

Scotty mentions how Admiral W. H. Smyth, observing in the 19th century with a 5.9 inch Tulley refractor, referred to this object as a “pale uniform disc about the size of Jupiter” (pp 124).

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Author’s note: Surely this is a gross underestimate of its true size! More like three Jove diamters. Smyth was right on the money about its hue however, as something this faint will not yield colour to the eye in all but the largest telescopes. Photographically, that’s a different matter however, as the image above illustrates.

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“It’s only a short hop,” Scotty says, “of 0.8 degrees northwest from M97 to the spiral galaxy M108, which can be seen in the same low power field.”

Yes indeed! Both objects are perceptibe in the same field of view of my 80mm f/5 refractor charged with an ocular delivering a one degree field. My 8 inch f/6 reflector at 150x shows 10th magnitude M108 to be a delicate sliver of light about four times as long as it’s wide. It also picks up the 12th magnitude star bleeding forth from near the centre of this edge on spiral galaxy.  This star, which is actually located well in the foreground of the galaxy, has doubtless fooled many an observer over the years into thinking it’s a supernova.

From here, Scotty describes how to find M109 and M106, together with interesting historical titbits, well worth reading(see page 125).

Scotty then focuses his attention on the sky inside the Bowl of the Big Dipper;

The Dipper’s Bowl also contains a fair number of 11th magnitude galaxies and fainter galaxies which generally go unmentioned in amateur observing guides.

pp 125

While Scotty mentions several NGC objects I have not personally observed, the one exception is NGC 4605, which is easy to see as a fuzzy oval in my 80mm refractor at 50x. Shining with an integrated magnitude of +10.9, it presents as rather mottled at 150x in my 8 inch reflector. Here’s how Houston describes it:

This 10th magnitude spiral lies nearly on the extension of a line joing Gamma and Delta Ursae Majoris. It is obvious in 65mm binoculars , and a large telescope makes it a fine sight, extending across a 5′ x 1.2′ area of sky.

pp 126.

On pages 127 through 129, Twinky discusses the curious mystery of M102, and specifically how it was misidentified as a duplicate obsservation of M101. Or, if you were to believe Admiral W.H. Smyth, it is to be identified with NGC 5866. Irrespective of what version of history you agree with, NGC 5866 is easily seen in my 5.1 inch f/5 reflector at 85x as a beautiful sliver of light with a highly condensed centre. You can find it manually by moving your ‘scope about 4 degrees south of the magnitide 3 luminary, Iota Draconis. My 8 inch reflector at 200x shows a very prominent dust lane coursing through its midplane.

NGC 5866 is alovely sight in a modest backyard ‘scope at high power. Image credit: Wiki Commons.

The memory of winter begins to ebb in June as mild but crisp nights complement the celestial riches now in the sky. Arcturus shines overhead, and Corona Borealis, the Northern Crown, is at its dainty best. Draco coils its pinpoint stars about the ecliptic pole, and the great globular cluster M13 is climbing up the eastern sky. It doesn’t matter if you use binoculars or a 20 inch telescope, there is so much to see that you wish for an impossible succession of crystal clear nights; but where to begin?

pp 129

Scotty clearly thought of everyone when he wrote his monthly deep sky observing columns. There’s enough for each and everyone to enjoy, using whatever equipment one chooses. Where Scotty lived, Arcturus passes overhead. But at 56 degrees north, it can never reach such heights.

Scotty next calls our attention to a curious triangular patch of sky, the vertices of which are marked by three stars; Eta Ursae Majoris, Alpha Canum Venaticorum and Gamma Bootis. Wiithin such a triangle, more or less, three prominent Messier galaxies can be found; M51, M63 and M94.

He begins appropriately enough with the Whirlpool Galaxy (M51), easily located by panning your telescope a shade less than 2 degrees southwest of Eta Ursae Majoris. Scotty presents this wonderful face on spiral galaxy in curious terms;

The Whirlpool offers challenges for any telescope. For example, what is the smallest aperture required to reveal the spiral structure? Lord Rosse first detected spiral structure when he turned his giant 72 inch reflector on the galaxy in the spring of 1845. Today, with our vision sharpened by knowledge, the spiral features of of M51 are visible in instruments as small as 10 inches , and some observers have glimpsed them in a 6 inch telescope in very dark skies. An 8 inch is sufficient for me, but John Mallas needed a 12.5 inch in a dark desert sky. He correctly noted that experience and exceptional transparency are important for success. In 1936, I had a very good view of the spiral structure using the University of Arizona’s 36 inch reflector in Tucson.

pp131

The wonderful Whirlpool Galaxy (M51) in Canes Venatici. Image credit: Wiki Commons.

Author’s note: I fully concur with Houston’s comments on this fascinating object. By far the finest view I have personally experienced of the spiral structure of M51 was through a good 16 inch reflector at an altitude of over 8,000 feet in the White Mountains of northeastern California. It was an amazing sight in those dark and crystal clear skies; it embodied a somewhat translucent appearance, more like living protoplasm than anything else. Such a memory is very hard to erase from the mind’s eye!

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On page 132 Scotty discusses M63, famous for its weird and wonderful spiral arms, found by moving the telescope about two thirds of the way from Eta Ursae Majoris to Alpha Canum Venaticorum. The latter system is better known as Cor Caroli, a splendid double star for the large binoculars or a small telescope. My 80mm f/5 refractor at 50x thows up a beautiful scene consisting of a blue white primary, magnitude 2.9, separated by about 19″ of dark sky from its yellowish secondary (magnitude 5.5). Nature is full of beautiful things that are easy to see and find!

On pages 134 through 135, Houston presents an excellent overview of what he calls, “the Wonder of M106.” To locate it, I find it easiest to start at Chi Ursae Majoris and then move 5.5 degrees or so eastward into Canes Venatici. This is a big (20′ x 9′) and bright galaxy (magnitude 8.3). My 8 inch reflector throws up a wonderful view of this grand spiral at powers of 150x or so, and even shows distinct signs of mottling (owing to prominent dust lanes, I suppose) in its spiral arms with a concentrated gaze.

The magnificent spiral galaxy M106 as imaged by the Hubble Space Telescope. Image credit; Wiki Commons.

Concerning M106, Scotty declares:

Ronald Morales viewed M106 with his 10 inch Newtonian reflector. Using a power of 87x, he described it as “extremely large; very bright with a bright, compact center; extended in a north to south direction with a large, fuzzy outer envelope.” Years ago in Kansas  I viewed the galaxy with a 10 inch reflector at about the same magnification and saw a “very bright parallelogram shape with fragile spiral arms at the end of the major axis.” The nucleus appeared uniform with little variation in brightness,. Other observers using 8 inch telescopes have reported M106’s appearance as long and needle like, and one saw a dark area near the nucleus. So much for consistency!

pp 135.

Scotty wanders into the constellation of Coma Berenices for the next section of this chapter. Bereft of stars brighter than about the 4th magnitude, the eye is naturally drawn to its northeastern corner where one can make out a very extensive haze of celestial light covering about 4.5 degrees of sky. This is Melotte 111, or the Coma Berenices Star Cluster. Scotty says opera glasses, providing a magnification of just 2x or 3x (pp 136) work wonders with this bona fide cluster of stars, where about three dozen luminaries can be made out, ranging in glory from the 5th to about the 10th magnitude.

From here, he continues to discuss the three globular clusters present in Coma. M63, he says, is unimpressive in a 3 inch telescope, but magnificent in a 12.5 inch. Then there’s 11th magnitude NGC 5053 about which he says, “in large instruments it is a little gem of woven fairy fire.”

What a wonderful turn of phrase!

Moving into Virgo, Scotty preserves a curious project that dates to the time of Sir William Herschel:

There is a strip of sky here near declination +02 degrees where several galaxies and a beautiful globular cluster can be readily located by means of a technique that dates back to William Herschel. The procedure is simple; set your telescope on a prearranged starting point, leave it stationary, and watch celestial objects drift through the field according to a timetable. For this purpose, select a low power eyepiece with a field not much less than 1 degree across. To check the field size of an eyepiece, time the drift of an equatorial star centrally across it, and count one minute of arc for every four seconds of time.Once that’s completed select a star lying west of the desired galaxy, but having the same declination. The telescope is then left stationary, allowing diurnal motion to carry the object into the center of the field.

pp 138

Scotty goes on to show how this age old technique, involving little or no modern technology, can enable you to see the edge on spiral galaxy NGC 5746 and a globular cluster in the same field! See pages 138 through 140 for more activities of this ilk.

There is never a shortage of deep sky objects. Whatever the season, the sky holds more than enough of these delights to keep you busy all night, every night; if you take the time to search them out with good charts and reference books……

pp 140

Scotty clearly believed that an amateur astronomer was responsible for his/her own entertainment, however unusual or off the beaten track it might seem to others. Enthusiasm (and not necessarily elaborate equipment) is the key to unlocking such treasures; activities that can keep a star gazer happy for a lifetime.

The interacting galaxies in Corvus known as the Antennae. Image credit: ESA.

The final pages of the June chapter discusses a number of objects in Corvus,  a constellation this author is not familiar with owing to its low position below the ecliptic upon culminating the southern horizon as well as the full blaze of twilight experienced during the summer months. Nonetheless, on pages 140 through 145, Scotty discusses a number of interesting objects within the sky enclosed by the stars of the celestial Corbie. Arguably the most interesting is the famous Ringtail Galaxy, or the  Antennae. Here’s how Scotty describes it:

Several times amateurs have sent descriptions of what they believe is this galaxy, but I’m sure they believe they have mistaken another galaxy for the Ringtail. My 5 inch 20x Apogee refractor shows the pair as a bright blob. An observation made with my 4 inch Clark refractor under the indifferent skies of my old home in Haddam,Connecticut, revealed NGC 4038/39 to be alittle more than an assymetrical 11th magnitude blur. However, at a campsite near Big Sur, California, I viewed a wealth of detail in the Ringtail with a borrowed 12 inch reflector. Other reports in my files support this…

pp 145.

At the end of this chapter, Scotty returns northwards into Virgo, where he discusses the Sombrero Galaxy (M104), a far lovelier sight in April than in June at my location. My 5.1 inch reflector at 100x can just begin to show me the dust lane in this edge on spiral galaxy, though Scotty claims that the experienced deep sky observer, John Mallas, couldn’t detect it in a good 4 inch refractor (pp 146). It’s obvious in my 8 inch reflector though at similar powers. And while you’d be mistaken for thinking that it’s a bona fide part of the Virgo cluster of galaxies, M104 is actually located some 25 million light years closer to the solar system.

The inspiring Sombrero Galaxy ( M104) in Virgo. Image credit: Wiki Commons.

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Author’s note: Scotty’s claim of Mallas being unable to clearly see the dust lane in a fine 4 inch f/15 refractor (that’s what he used!) resonates quite well with the author’s experience on another target; the faint double star, Pi Aquilae. In other work, it was shown that this pair of stars (magnitude 6.3 and 6.8), separated by 1.5,” was a challenging target for a 4 inch f/15 refractor (illustrated earlier)  but was considerably easier with a 130mm f/5 Newtonian. The reason was simple; the 4 inch runs out of light earlier than the 130mm, so at the magnifications employed (approximately 270x) it’s just easier to see these stars as separate in the larger aperture Newtonian. The same is probably true of the Sombrero.

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Chapter 7: July

By now, the shortest nights have passed away and Scotty gets his teeth stuck into the wealth of wonderful objects on view during the longer nights of July. Personally, this is one of my favourite chapters from the book,  as it covers such a wealth of familiar objects I like to visit as a casual (read non serious) deep sky observer.

The opening pages (131 through 134) of this chapter are dedicated to a seasonal favourite and, historically speaking, a very important celestial treasure in the sheme of things; the famous planetary nebula in Draco, NGC 6543, more affectionately known as the Cat’s Eye Nebula. This 9th magnitude object is fairly easy to track down about 5 degrees east northeast of the third magnitude sun, Zeta Draconis.To my eye, this is one deep sky object that actually resembles the name bestowed upon it; a blue green feline eyeball staring back at you from the depths of space. In my 5.1 inch reflector at 100x, it is quite large; about 18″ in diameter. The central star is clearly visible; quite a feat when you think about it, as it is a hot and highly luminous white dwarf star much smaller than the Sun, and shining with an equivalent brightness of an 11th magnitude star. I find the view at 200x in my 8 inch reflector to be nothing short of stunning!

The famous Cat’s Eye Nebula in Draco as imaged by the Hubble Space Telescope. Image credit: Wiki Commons.

Scotty describes what NGC 6543 looks like in all sorts of equipment, including the homemade 1″ refractor he first spied it through as a boy. It also includes a description of the view experienced by a one Michael  Gardner through the 60 inch reflector atop Mount Wilson in California(152/3). Scotty also informs us that the English amateur astronomer, Sir William Huggins, examined this planetary nebula with a crude spectroscope attached to an 8 inch refractor back in 1865, finding it to be quite distinct from any stellar body he had previously examined!

In the next few pages Scotty turns his attention to two varibale stars in the constellation of the Northern Crown; Corona Borealis (T CB and R CB).

At his location, at mid northern latitudes, July is an excellent month to track down some of the finer globular clusters in the summer sky and Houston wastes no time discussing these fascinating objects in detail, including M13 and M92 in Hercules, the ‘rival of M13’ in Serpens, M5 as well as a string of globular favourites down in Ophiuchus (pages 157 through 165). The reader is warmly encouraged to sift through this excellent literature and put some of Scotty’s suggestions to the test.

It’s always nice when Scotty includes a double star of note in his monthly columns (the ‘deep sky’ objects I am most acquainted with). In this capacity, he mentions the charming little binary system, 70 Ophiuchi on page 166;

In 1989, the 4.3 and 6.0 magnitude components were near a minimum separation of 1.5″

pp 166

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Author’s note: 70 Ophiuchi is a beautiful colour contrast double star system, consisting of a yellow primary and orange secondary, orbiting their common centre of gravity in 88 years. A perennial favourite, the pair is currently widening towards their maximum separation, which will occur around 2025, after which time they will slowly close in on each other again. Currently, they are easily separated in a 60mm refractor but will require something closer to 80mm as they close in over the years (minimum 1.5″).

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While you’re at it, Scotty recommends scouting out the bright (magnitude 8)  planetary nebula, NGC 6572 (a.k.a The Emerald Nebula), discovered by the famous double star observer, Wilhelm Struve, back in 1825. About the same size as the Cat’s Eye Nebula (18″) discussed previously, it’s a good target for a medium sized backyard ‘scope at high power. You’ll find this object in a low power field about 2 degrees south of the star 71 Ophiuchi.

Warm summer nights are a fine time to relax under a dark sky. As you lie back and scan the ghostly band of the Milky Way and its environs, see how many globular clusters you can detect with the unaided eye. If you observe from mid northern latitudes and can detect 6.5 magnitude stars, there are eight globulars to try for this month in the evening sky; M2 in Aquarius, M3 in Canes Venatici, M4 in Scorpius, M5 in Serpens(Caput), M13 and M92 in Hercules, M15 in Pegasus and M22 in Sagittarius.

pp 168

From a good, dark site, such globulars all seem observable with the naked eye but, as Scotty reminds us, the above assumes they are point sources. And that is not the case, as even through a finder telescope, they present as distinctly non stellar. But what a challenge nonetheless!

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Chapter 8: August

The regions near the north celestial pole are usually neglected by amateurs, who seem more attracted to the spectacular sights farther south. But sometimes we overlook the obvious. Polaris, for example, is a variable star. In fact, it is the brightest Cepheid in the sky.  Sky catalogie 2000.0 gives its range as 0.15 magnitude over a 4 day period, but studies done during the 1980s show that the range is decreasing, leading some astronomers to speculate that the star may cease to vary altogether. Currently Polaris varies by only a few hundredths of a magnitude and is thus well below the range detectable by the eye.

pp 173

With these words, Scotty opens his chapter on the August sky. He takes us to the Pole Star, around which the great vault of heaven rotates, in this epoch at least.  He does mention later (but not here), that Polaris is a multiple star system; with Polaris B being easily accessible to a small backyard telescope. The companion is a lovely sight in my 80mm f/5 achromatic telescope at 50x.

That said, having explored the book’s content thus far, one comes away with the distinct  impression that Scotty wasn’t an overly enthusiatic observer of double stars. Instead he quickly alerts us to a very faint (13.5 magnitude) spiral galaxy, NGC 3172, discovered by Sir John Herschel in the early 19th century, which he christened, “Polarissima”. Needless the say, I’ve not seen it, nor looked for it. Scotty recommends an 8 inch or larger instrument to bag this bounty from the sable depths.

Sticking to far northerly targets, Scotty then moves into Cepheus, and to the open cluster, NGC 7380. You can track this 10th magnitude target down fairly easily, as it lies just a shade under 2.5 degrees east of that most famous of Cepheids; 4th magnitude Delta Cephei. In an area of sky about the size of the full Moon, my 8 inch pulls in about 20 or so stellar members of the 10th magnitude. Inserting a nebula filter will help bring out the brighter parts of the nebulosity associated with it; Sharpless 2:142

NGC 7380 and its associated Nebula imaged using narrow band filters. Image Credit: Hunter Wilson.

In my 8 inch Newtonian at 100x it shows up as a faint, misty fog on a dark night with good transparency.

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Author’s note: Insert a low power eyepiece and revisit Delta Cephei. It has a magnitude 6.3 companion wide away which contrasts beautifully with the rich yellow hue of the primary. It makes a very fetching site in my 80mm telescope at 50x and is also an excellent binocular double.

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The most northern galactic cluster in the sky, NGC 188, is also one of the oldest known, 14 to 16 billion years. It is located just 4 degrees south of Polaris and 1 degree south of 2 Ursae Majoris;

pp 175

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Author’s note: In Scotty’s day, astronomers were not nearly as sure about a lot of things. NGC 188 is now believed to be of the order of 6 billion years old. There was also more unceratinty about the age of the cosmos back then. Today, thanks to refinements in the Hubble Constant (Ho), we are far more sure of its age; 13.799 billion years with an uncertainty of just 0.15 per cent.

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To real meat in this chapter is presented on pages 179 through 184, where he discusses some of the finest planetary nebulae in the northern heavens;

To some people, the ethereal gas bubbles of planetaries have a compelling pull all their own. They float on the foam of the Milky Way like the balloons of our childhood dreams, so delicate they appear. If you want to stop the world and get off, the lovely planetaries sail by to welcome you home.

pp 179.

What a sweet sentiment; to ” stop the world and get off.” Stargazing certainly can do that!

Scotty starts with by far the most famous and well known planetary nebula, easy to find about midway between Beta and Gamma Lyrae; the famous Ring Nebula (M57). Accessible to most any telescope, it’s an enjoyable sight at 100x in my 80mm shorttube refractor, but far more compelling in my 8 inch reflector at the same power.

The magnificent Ring Nebula( M57) in Lyra. captured here by Hubble Space Telescope. Image credit: Wiki Commons.

Appearing a bit more than 1′ across, M57 looks like a 9th magnitude star in finders. The Apogee telescope shows the ring as very bright, but no other detail is visible. At powers of 250x and up, a curious effect takes place. The oval outline of M57 takes on a lemon shape with the ends of the oval appearing rather pointed. They also appear more diffuse and wispy. A power of 600x, however, is none too great if there is sufficient aperture to support it. Even at high magnification, the interior of the nebula retains a thin film of haze that can show some structure.

pp 180/1

Scotty’s comments about this planetary are spot on. M57 looks better and better in larger and larger telescopes. You need large apertures to sustain the very high powers required to discern some of the features he describes. Small ‘scopes just run out of light on this object, limiting the magnifications one can profitably adopt. 200x is a nice place to be with M57 in my 8 inch reflector.

On a top class night, a 12 inch or even a 10 inch telescope can show the planetar’s central star In moments of exceptional atmospheric conditions a 12 inch or larger instrument may reveal a scattering of stars across the central vacancy and even amid the ring itself.

pp 181

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Author’s note: Despite having many, many goes, I have never been able to see the central star in M57 with telescopes of the size described by Scotty. I suspect you’d need a telescope of 20 inches of aperture in this country, and great weather to boot, to have even half a chance to bag this baby!

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On pages 182 through 184, Scotty switches subject to discuss the equally interesting Dumbbell Nebula (M27) in Vulpecula.  Scotty offers a neat way of finding it without setting circles or GoTo:

Set your finder on Gamma Sagittae, the head of the celestial arrow. Sweep about 5 degrees north and you should see an M shaped pattern of stars composed of 12, 13, 14, 16 and 17 Vulpeculae; this group is more conspicuous to the eye than most star charts lead you to believe. M27 is just 0.5 degrees south of the M’s central star.

pp 183.

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Author’s note: M27 is a fascinating telescopic object! It’s huge; fully five times larger than the Ring Nebula but because its light is spread over much greater area it has much lower surface brightness. My 5.1 reflector at 20x easily shows the two bright lobes in an eerie greenish hue. It looks even more compelling in 8 or 10 inch aperture ‘scopes but I find it doesn’t respond well to over magnification;150x to 200x seems about optimal to me. Nebula filters (particularly an OIII)  also work well with larger apertures. Its 12th magnitude central star remains elusive in all but the largest backyard ‘scopes.

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The Dumbbell Nebula ( M27). Image credit: Mohamad Abbas.

Scotty seems somewhat ambivalent concerning the ‘optimum’ sized telescope to view M27 but rightly recognises the importance of aperture;

It is hard to assign a “best” type of telescope for viewing M27. My 5 inch Apogee telescope with a fixed power of 20x shows it as a bright sphere with the dumbbell shape rather mild. My 10 inch f/8.6 reflector shows M27 much better at 300x by means of a Barlow lens less than at the same power with a short focus eyepiece. The latter left the sky gray, and contrast with the nebula was poor.

pp 183

Where Scotty lived out much if his life, the Milky Way in August must have been a wonderful sight, with Scorpius, Scutum and Sagittarius riding a respectable height above the horizon at midnight. Up here on the ‘edge of the Arctic Circle’ only the glory of the northern Milky Way manifests itself. Houston had a habit of asking questions, which at first seemed trvial, but upon reflection, were quite difficult, if well nigh impossible, to answer.  Once such question is this? Where does the Milky Way’s Way edge lie? On pages 186 if discusses this strange question but seems to conclude that, like everything else, it’s dependent upon the kind of ‘filter’ one’s local conditions impose. Whimsically, he calls it ” Houston’s Uncertainty Principle.”

To be continued in Part 2

De Fideli.

Tales from the Golden Age: Hunters of the Red Stars.

The brilliant red giant star, Betelgeuse, shining in the northern winter sky.

 

 

 

 

 

 

 

Do the words of a poem lose their poignancy once its author departs this world?

Can the limp of ‘progress’ outshine the ‘grand procession’ of great accomplishment?

Can a culture, basking in the glory of its own achievement, be made mute by a faithless generation of technocrats?

Can an optical bench test inspire more than a night spent behind the eyepiece of a grand old telescope?

Let us venerate that which is deserving of veneration!

Whose crown shall we adorn with a laurel wreath?

Let us sing again of old dead men

 And clear the cobwebs from their medals.

For they have no equal in the present age

No muse to light their way.

 

 

 

Anno Domini 1866; the Leviathan of Parsonstown, with its six–foot primary mirror, reigns as the largest telescope in the world, bringing international prestige to Irish astronomical science; and both Dublin and Armagh have well established observatories that date back to the end of the 18th century. Their administrators are formally trained, their observing programs, specialised. But far from the Irish cities, west of the great Shannon River, a 50–year–old gentleman, hitherto unknown to the astronomical community, was strolling home along a narrow dirt road that wound its way north from the small town of Tuam, County Galway. It was shortly before midnight on the evening of May 12, that he saw a 2nd magnitude star he had never noticed before in the constellation of the Northern Crown, then situated very high in the sky. After reaching his home at Millbrook House, he sat down by the light of a paraffin lamp to check the star charts in his library. To his amazement, the only star recorded in the position he estimated was of the 9th magnitude, far too faint for even his keen eyes. He had just discovered the brightest nova to grace our skies since 1604; the star T Coronae Borealis!

Such was the meteoric arrival of John Birmingham (1816–1884) upon the world’s stage; an accomplished poet, land owner and man of letters. John was born the son and only child of Edward Birmingham and Elly Bell, who set up home at Millbrook House, near the village of Milltown, from which they received a comfortable income as landlords of a small landholding, itself part of the greater Millbrook Estate. He was educated at St. Jarlath’s College in the nearby town of Tuam and grew up to become a fine figure of a lad, both stronger and taller than many of his peers. Though there is no evidence that he attended university, we may infer from his lifelong interest in scientific matters, particularly geology, as well as his noted ability as a writer, he received an excellent and well balanced education, acquiring significant scientific knowledge from the greater popularisers of his day. Records do show however, that he was actively involved in famine relief during the years 1846 and 1847, which claimed the lives of a million people; about one eighth of the population; from starvation or the associated epidemic disease that swept the nation between 1846 and 1851. Another two million souls emigrated in a period of a little more than a decade (1845-55).

Birmingham spent about six years travelling through Europe in the late 1840s through to the mid 1850s, learning the language and culture of the nations he visited, and spending the majority of his time in Berlin, where he eked out a living from the circulation of interesting scientific articles for popular journals and newspapers, often writing under a pen name. It was here also that historians suggest he had his first encounter with the astronomical world. In particular, he took a great interest in the work of the famous German astronomer, Johann Franz Encke (1791–1865), with whom he established a strong bond of friendship. Birmingham returned to his ancestral home in the late 1850s, ostensibly acquainted with the language and literature of the French and German tongues.  The skies in this part of Ireland were often overcast and dominated by weather systems rolling in from the nearby Atlantic, but on clear evenings, the sky would have been gloriously clear and wonderfully transparent, purged of dust and other particulates; skies that would have commanded a visceral sense of awe and wonder in the young Irishman.

Johann Franz Encke (1791–1865), German astronomer. Image credit: Wiki Commons.

By all accounts, his earliest astronomical equipment was very modest; most likely a small spyglass delivering a fixed magnification of 23x, but it is clear from his later discovery that he cultivated an excellent knowledge of the naked eye heavens. The apparition of Donati’s Comet in 1858 and the Great Comet of 1861 induced great excitement in Birmingham, penning a string of prize winning essays on their appearance and significance;works which appeared in some of the most prominent British and Irish newspapers of the time. But his political connections raised eyebrows among some members of the Imperial establishment. The silver tongued Birmingham was a patriot and associated with British politicians sympathetic to the cause of Irish independence.

Perhaps the latter fact helps to illuminate the bizarre way in which the discovery of the eruptive variable star was made known to the outside world. In the wee small hours of May 13, Birmingham drafted a letter to the editor of the London Times and promptly despatched it. It landed in the hands of the editor a few days later, who, after reading it, promptly discarded it in a waste paper basket! When no acknowledgement was received by Birmingham, he decided to bypass the standard modus operandi of contacting the observatories at Dunsink and Greenwich, and instead wrote of his discovery to one of the most accomplished and respected British astronomers of his day; William Huggins (1824–1910), pioneer in astronomical spectroscopy, who ran a very well equipped private observatory from his home at Tulse Hill, London. This time it was well received, and Huggins enthusiastically turned his spectroscope toward it on the evening of May 18, finding it to be quite unlike anything he had ever seen before! A normal stellar spectrum presents as a streak of colours as in a rainbow, with faint dark lines. The spectrum of T Coronae Borealis, on the other hand, presented with very bright emission lines thought to be due to superhot hydrogen gas. Indeed, Huggins believed that the star had ejected a shell of excitable matter.

Sir William Huggins(1824 –1910), a portrait by John Collier, Image credit: Wiki Commons.

Birmingham also wrote to his local newspaper, providing details of his discovery:

I discovered it on the night of the 12th instant, when it appeared the 2nd magnitude, rather more brilliant than Alpha of the above constellation, with a bluish tinge, forming nearly a right angled triangle with Delta and Epsilon. It had nothing whatever of a cometary aspect. The state of the atmosphere prevented my seeing it again until the 17th, when it appeared reduced to the 4th magnitude…….

It was Huggins who endorsed Birmingham’s discovery at a later meeting of the Royal Astronomical Society and, after word of his discovery spread throughout Europe, the German astronomer, Julius Schmidt, based at Athens, was able to confirm, by the consultation of his notebooks, that only hours before Birmingham noticed the brightening of T Coronae Borealis, the star appeared as it normally did. i.e. a faint field object in his 6 inch refractor. Indeed, Schmidt named a lunar crater after the Irishman, located near the Moon’s northern limb, presenting it in his famous map, first published in 1878.

Lunar Crater Birmingham, located by the Moon’s northern limb. Image credit: Wiki Commons.

The discovery of T Coronae Borealis dramatically changed the course of Birmingham’s life and from there on in, he dedicated himself to further astronomical observations. Realising that his existing equipment was not really up to the task of doing any serious telescopic work, he set about acquiring a suitably powerful instrument. Huggins had enthusiastically assisted Birmingham in his telescopic researches, warmly recommending that he acquire a moderate–sized Cooke refractor for the purposes of continuing his work. Indeed, we know that Birmingham had visited some acquaintances at Scarborough, a seaside town not far from where Thomas Cooke & Sons of York had set up their world renowned telescope making workshops. The instrument he finally acquired in 1869 was a fine 4.5 inch f/15 achromatic doublet, purchased for the princely sum of £120 (still a very large sum by Birmingham’s standards). Curiously, the object glass of the telescope was rumoured to have been made by Howard Grubb of Dublin.

But what, pray tell, would he employ this quality telescope to do exactly? This became over more clear by the opening years of the 1870s, after he struck up a correspondence with one of the great amateur astronomers of his age; the Reverend T. W. Webb, who suggested that he take up the task of hunting down and cataloging the positions and magnitudes of red and orange stars some of which would be variable, a project that was only partially addressed in earlier decades by Sir John Herschel (1792–1871) and the celebrated binary star observer, Friedrich Wilhelm Struve(1793–1864). In addition, the Danish astronomer, Hans Schjellerup (1827–1887), who compiled a list of 280 red stars published in 1866 in Astronomishe Nachricten. His 4.5 inch aperture, long focus achromat would be able to reach stars down to the 12th degree of glory, and with a special, low power eyepiece delivering a power of 53 diameters, he would be able to scan (fairly) large fields of sky. So, the middle–aged amateur from the wilds of the Emerald Isle set about his new avenue of astronomical enquiry; a task he enthusiastically embraced with both hands!

Tiberius; the author’s 5″ f/12 classical refractor; a very similar instrument to that employed by John Birmingham, and used for the purposes of reconstructive history.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Brimingham devoted the next four years of his life searching the sky for red and orange stars. His copious notes show that he would often begin after supper and work all the way through until dawn, weather permitting. Such devotion reflected, at least in part, his bachelor status. He never married and is rumoured to have fathered a child (female).

He was acutely aware of the rather subjective nature of accurately assigning colours to the stars he observed. In particular, his continual correspondence with Webb alerted him to the inherent weakness of the refractor in revealing the true colour of stellar bodies and how the new silver on glass Newtonian refelectors, with their perfect achromaticity in comparison to the former, might be better tools for carrying out such delicate work. We do know however, that Birmingham had the presence of mind to include, where possible, relevant comments from other observers who, at his request, had examined the same stars. He also estimated their brightness in comparison to other field stars. Most of the stars he listed he came across were brighter than magnitude 10 but quite a few were as faint as magnitude 12. During the course of his surveys, Birmingham became intensely interested in the spectroscopic work of Father Angelo Secchi, who had himself collated a list of over 400 coloured stars in 1872 and had begun to subdivide stars into five spectroscopic types. It was during these years that the concept of stellar evolution was first entertained, an idea that greatly appealed to Birmingham and which provided further impetus to continue his surveys.While compiling his list he included Secchi’s available spectral data with his visual notes.

Birmingham’s work cullminated in a list of 658 orange and red stars, published under the title: The red stars: Observations and catalogue, which he presented to the Royal Irish Academy on June 26 1876. The work was enthusiastically accepted and published in August 1877. It is clear from the work that he owed an especial debt to Webb, who had examined about 80 of the stars in his catalogue and provided his own notes on their colour and brightness. Birmingham was also generous to a fault in providing full acknowledgements to all other collaborators.

The red stars also contains very interesting speculations concerning the nature of variables; how and why they brightened and faded. He had himself noted subtle changes in the colour of red variables. In particular, their colour often became paler to his eye as they brightened and deepened in hue as they faded back. This suggested to him that such stars were not dying, as many of his contemporaries held. He also dismissed the idea that the variation in such stars was due to stellar rotation. Birmingham offered his own explanation to explain the variable nature of these red stars, which, in his own words, involved, “the intervention and recession of a nebulous belt around the star.” Taking inspiration from the reddening of the Sun as it approached the horizon (what we refer to today as Rayleigh scattering), Birmingham believed an annulus of dusty material of varied density around such stars could cause them to dim and brighten.

Birmingham was the first observer to note that red variable stars were unevenly distributed in the heavens, being more highly concentrated in a large patch of Northern Milky Way taking in Lyra, Cygnus and Aquila; a swathe of sky he referred to as the “Red Region.”

In the years after the publication of his catalogue, Birmingham became increasingly involved in the spectroscopic designations made by his peers across Europe. For example, he queried Secchi’s assignment of the newly discovered Wolf–Rayet stars to Type IV, and was rather annoyed when the Roman Padre expressed his scepticism that there really existed a concentration of such stars in certain regions of the sky. John’s original work provided fertile ground for other observers to carry out new surveys for red stars. Indeed, Birmingham issued two voluminous addenda featuring a new list compiled by the astronomer, Carl Frederik Fearnley, and another taken from the double star lists of Struve and Herschel.

In the last years of his life, Mr. Birmingham continued to search the skies for more red stars with his 4.5 inch refractor and discovered yet another red star in Cygnus in 1881. He continually updated his list with new spectral data which was streaming in from observers on the continent. In the last year of his life, the Royal Irish Academy, convening at Dawson Street, Dublin, presented Birmingham with its prestigious Cunningham Gold Medal on January 14 1884 for his distinguished astronomical career. Its President, the poet Sir Samuel Ferguson, honoured him with these words:

If I might express an individual opinion I would say that…..you content yourself with noting facts; and shunning plausible but doubtful methods of accounting for them. It is thus [that] solid knowledge is ultimately attained to. Of you let it be said, itur ad astra. Proceed, with the best wishes of the Academy, in your philosophic method, and bear back with you to the Bermingham country this medal, as a token and assurance to our brethern beyond the Shannon that wherever Irishmen devote their leisure to higher learning, there exists for them here, in the capital of their own part of the United Kingdom, a body having perpetual succession, and speaking with the voice of the constituted authority, whose business it is to sympathise with them, to encourage and reward.

This was but one of many accolades delivered to the Tuam astronomer but they were ultimately powerless to change the personal circumstances of his life. The Irish Land League was established with the primary aim to abolish landlordism in Ireland altogether, and to enable tenant farmers to own the land they worked on. As a result, many of the tenants paying rent to Birmingham refused to do so. In addition, he had to fight a succession of legal threats to the title of both his lands and his house. Collectively, these events left him seriously short of income, which resulted in his slump into poverty. Indeed, one of his own tenants described the desperate state of his last days; “he [Mr. Birmingham] was all spent up and starved with the hunger.” He passed away in the early hours of September 7 1884, aged 68 years.

In the aftermath of his death, Birmingham’s house and estate were ransacked and rendered derelict, with much of his written notes and books burned or left to the elements. And what remains of Millbrook House is a but a ruin to this day. Only his wonderful telescope survived, which was preserved for many years at his alma mater, at St.Jarlath’s College, before being handed over to the Milltown Community Museum for posterity.

And yet, all the while, Birmingham’s work was not done in vain, for it was to be taken up once more by a most eccentric Anglican clergyman: Thomas Henry Espinell Compton (T.H.E.C) Espin (1858–1934) who, with singular enthusiam, greatly advanced the story of the red stars.

Espin, the only child of the Reverend Thomas Espin, chancellor of the diocese of Chester, was born in the city of Birmingham on May 28 1858. At age 14, Espin entered the elite boarding school for boys at Haileybury, where his headmaster, himself an astronomy enthusiast, encouraged and instructed his pupils in basic astronomical knowledge. It was the appearance of Coggia’s Comet in the sky in 1874 that really stoked his interest in all things celestial. From 1876 to 1878, he was sent to France to complete his secondary education before going on to Exeter College, Oxford University in 1878 to read for a degree in theology, for which he obtained a good honours degree. Here, his interest in astronomy flourished further when the Savilian Professor at Oxford, Charles Pritchard, allowed him to use the 13 inch De La Rue reflector of 10 foot focus at the university on the condition that he provide practical instruction to other students. It was an offer Espin could not refuse. And he excelled at what he did best; fill people with a sense of wonder and awe for the Universe, as revealed by the telescope. By January 11 1878, aged just 20, he was elected a Fellow of the Royal Astronomical Society(FRAS) during the presidency of Sir William Huggins.

On leaving university, Espin took holy orders, following his father into a clerical career in the Anglican Communion, accepting curate positions first at West Kirkby, Wallasey and Wolsingham in 1881, 1883 and 1885, respectively, before finally taking up permanent residence as Vicar of Tow Law, County Durham, in 1888; a post he was to retain for the rest of his life. In 1880, while at Wallasey Rectory, Birkenhead, Espin wrote to the English Mechanic, proposing the formation of an amateur society aimed at organising and coordinating observations and that the best way to do so was to arrange meetings where local amateurs could discuss their observations in an open and congenial manner. The following year, 1881, the Liverpool Astronomical Society was founded.

After inheriting his father’s estate, he became financially independent, allowing him to pursue many avenues of independent scientific research, much in the same vein as Birmingham before him, including geology, botany and photography. He was an avid student of paleontology, amassing an impressive variety of fossils during his long career; a study that led him to firmly (and rightly I might add) conclude that Darwin’s theory of evolution was bogus. He was also a keen microscopist, with a encyclopedic knowledge of cell biology and the behaviour of Protozoa. Intriguingly, Espin was one of the earliest pioneers in the study of X–rays, and enjoyed using his parishioners as ‘guinea pigs’ in his early experiments!

Espin regarded his vicarage as an ‘open house’ that could be visited any time by his parishioners. They must have been fascinated by his vast collections of books, plants, rocks, fossils and aquaria to cultivate his ‘animalcules’ and pond weed for the microscope. Afterall, he was, like John Birmingham also, a lifelong bachelor. In his garden, he established a small sanatorium in order to provide his sickly ‘flock’ with some relief from the consumption (Tuberculosis). He turned the basement of his home into a gymnasium and even set up a rifle range on his grounds for use by the parish ‘lads.’ All of this was done at the expense of not providing the traditional pastoral care for his parishioners though; he didn’t do house visits. And to top it all off,  he was a well travelled gentlemen and a formidable biblical scholar.

As a boy, Espin explored the heavens using opera glasses and enjoyed a 1 inch aperture Dollond refractor as his first telescope. By the time he entered Oxford University, he was using a 3 inch refractor for his own recreation. Some time later, Espin was presented with a 5 inch refractor by the head of the Harrison line of steamers, a Churchwarden at his old parish of Wallasey, which he used to good effect. While at Wolsingham, Espin set up his first makeshift observatory using the 5 inch refractor and made regular observations through it until he secured his permanent post at Tow Law.

As Webb’s righthand man, Espin assisted his famous ‘elder statesman’ in several revisions of his celebrated Celestial Objects for Common Telescopes. And it was also Webb who piqued Espin’s interest in a fabulous new line of reflecting telescopes being fashioned by master opticians such as George Calver and George With. With these novel instruments he was able to carve out his own unique legacy in the annals of astronomical history. Their generous apertures, much lower cost than traditional refractors, as well as their freedom from chromatic aberration made them a very popular choice for a new generation of amateur and professional astronomers alike. And it was Webb himself who spearheaded this movement across Britain!

We shall not dwell on the historical evidence supporting the above assertion, for this will be covered far more extensively in a separate chapter of the book. That said, in the following excerpt, which is part of a written correspondence between Webb and a one Arthur Raynard, we gain a glimpse of his evangelism for the new silver on glass specula:

It might be worth your while to consider, before finally deciding, the comparative merits of the silvered glass reflector. You have probably heard of this beautiful instrument…. At present it is only in the hands of amateur makers, but their success has been remarkable. One of at least 8 inches clear aperture may be purchased in Hereford for about £26 or £27. As far as looks go, it is certainly very common and clumsy looking affair – being merely a great square tube of stained deal, mounted on a plain wooden stand – and if you regard appearances I could not say much for it. But the Newtonian reflector, under any circumstances, is a singular looking instrument.

Webb had himself proven the worth of these new instruments, acquiring a string of silvered mirrors and complete telescopes. Indeed, according to the noted British double star observer, Robert Argyle, they were able to resolve double stars well below one second of arc:

The 91/3 inch With Berthon reflector was obviously of high quality. One of the regular test objects used by With and Calver was γ2 Andromedae. The 8.5 inch mirrors of both makers were guaranteed to divide the pair, at a time when the separation was 0.6″. Webb also noted, in 1878, that he was able to suspect division in ω Leonis, then at 0.52″, and to divide η Coronae Borealis at 0.55″.

So much for the prognostications of the current generation of amateurs!

It was magic like this that convinced Espin to purchase his first truly ‘serious’ telescope; a 17.25 inch silvered glass reflector by Calver, purchased on Webb’s recommendation in 1885.

Octavius: the author’s 8″ f/6 Newtonian.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Espin most likely purchased the mirrors separately and had the castings for his Calver optics made to order by Lepard & Sons of Great Yarmouth and also by the agricultural firm, Suffolk Iron Foundry, then located near Stowmarket. Espin constructed a modest observatory based on the design of the Reverend Edward Lyon Berthon(1813-1899), another clerical astronomer, which consisted of a small circular equatorial room with a conical roof, and which was commonly known as a ‘Romsey’, after the Parish in which Berthon lived and worked. Espin likely mounted his new instrument on an early equatorial (sometimes called an ‘equestrian’) designed by George With and Edward Berthon (see below).

Shortly before his death in 1885, Webb had alerted Espin to the work of John Birmingham on the red stars. In the months before he died, Birmingham despatched much of his unpublished work to Webb, requesting that he might carry on his observations. Because of his many other duties and failing health, Webb was unfortunately unable to commit to such an undertaking, yet he found a willing and able disciple in the young and enthusiastic Espin.

The With/Berthon equatorial mount( BAA# 83) featuring the 9.33 inch reflector employed by T.W. Webb in his later career. It is likely Espin used a similar mount for his larger 17.25 inch Calver Newtonian. Image courtesy of Denis Buczynski.

 

 

 

 

 

 

 

 

 

 

 

A Curious Aside:

Which is a better tool for red star hunting: a 5 inch refractor or a 8 inch reflector?

A wee experiment: Octavius’ (8″ f/6 Newtonian), and ‘Tiberius’ (5″ f/12 glass) strut their stuff.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Method: A Baader 8 to 24mm zoom eyepiece was chosen to give an approximate exit pupil of about 2mm in both the 5” inch refractor and the 8” reflector, delivering powers of 64 and 100x, respectively. Both instruments were turned on the Double Cluster (Caldwell 14) in Perseus on a dark, moonless evening and the views compared, side by side, for several minutes.

Results: Though the images served up by both telescopes were very fine indeed, the easy winner was the 8” Newtonian. The contrast was a shade better in the unobstructed refractor, as one might expect, but the Newtonian, with its 22 per cent linear obstruction, wasn’t far behind it. These magnificent open clusters contain quite a few ruby stars of varying glory, but the greater light gathering power of the Newtonian (∼1 visual magnitude) made these stars considerably easier to pick out against a dark hinterland compared with the 5 inch glass. The colour of fainter members, in particular, was easier to discern in the Newtonian, a consequence, I suppose, of its greater ability to collect light. Put another way, where there is but a suggestion of colour in the refractor, it is clearly visible in the Newtonian.

From a practical point of view, it was also much easier to study these ruddy stars in the Newtonian, owing to its more comfortable eyepiece position whilst viewing an object high in the sky.

Comments: More light delivered to the retinal cone cells render colour vision more efficacious with the larger aperture. Indeed, no matter how much this author wanted the 5 inch refractor to win, owing to its elegant images, striking good looks, and much greater cost in comparison to the ‘glorified toilet roll’ that is the Dobsonian, it was never to be. Indeed, on all celestial targets examined, under reasonable to good seeing conditions, whether planetary, lunar, double star or deep sky, the Newtonian proved noticeably superior. A comparative MTF graph of a 5 inch refractor and 8 inch reflector will also show this clearly. Many lines of evidence lead to the same conclusion.

The 8 inch Newtonian was the superior instrument for hunting down and viewing red stars. This aperture is probably optimal for all kinds of general purpose viewing, including looking at red stars. Thoughtfully designed Newtonians can do wonderful things!  Here’s an interesting assessment made by a guy from Norfolk (England) of a similar telescope to the author’s modified Newtonian (in terms of raw aperture, coatings, and quality of secondary mirror), only with a slower f ratio and (slightly) smaller central obstruction.

Tiberius; Proxime Accessit.

Octavius; Optimus.

………………………………………………………………………………………………………………………….

With his newly acquired 17.25 inch Calver Newtonian installed, Espin, together with his paid assistant, William Milburn, began a new and ambitious search for red stars all across the northern sky. Over the next two years, he found an incredible 3,800 red stars, discovered many new nebulae and over 30 novel variable stars. Such work called for considerable industry and his preserved records indicate that during the dark winter evenings, observing vigils were maintained for over 13 hours! Using an entirely homebuilt spectroscope, he examined over 100,000 stars from Dr. Argelander’s preeminent star charts, with magnitudes as faint as +9.0.

These new data were included in a much more extensive edition of The red stars, which also included contributions from Webb, Copeland, Birmingham and Dreyer, and published, once again by the Royal Irish Academy in 1890. The same telescope was used by Espin and Milburn to discover 2,575 double stars, many of which were measured micrometrically to establish position angles and angular separations. Espin’s proven skill as an inventor was also seen in the many new astronomical devices he made with his own hands, including arguably the first zoom eyepiece offering an assortment of magnifications, a new kind of stellar camera, as well as an improved method of lighting the cross hairs of the micrometer.

To the general public, such routine work as this often went unreported, but Espin received international fame in November 1910 with the discovery of Nova Lacertae, which burst onto the scene with a peak magnitude of 4.6. Over the next 37 days, as the world’s largest telescopes were turned on it, the nova slowly faded back to 7.6 and today it is exceedingly faint at magnitude 14.

For his great contributions to astronomical knowledge, Thomas was awarded the Jackson Gwilt Medal of the Royal Astronomical Society in 1914 for his extensive spectroscopic work, as well as his discovery of Nova Lacertae. It was in the same year that Espin installed an even more powerful telescope at Tow Law; a 24 inch Calver reflector, with which he and his assistant continued to look for and measure new double stars. Curiously, Espin decided to concentrate his efforts on wider pairs, perhaps as a result of noting that the typical atmospheric conditions he enjoyed at Tow Law, Co. Durham, were rarely up to measuring very close pairs. This was the last telescope Espin would aquire and he used it faithfully right up until two years before his death on December 2 1934, aged 76.

                                       The nature and significance of red stars

Red stars, which include the spectral classes M, R, N and S, are not only visually striking to the human eye, standing out against the darkness of the night sky more readily than those with different hues, but they are arguably some of the most fascinating to study! First off, red stars not only include celebrated giant stars such as Betelgeuse, but they also incorporate the smallest bona fide stars in the firmament; the cool dwarf stars that comprise maybe 70 to 80 per cent of all stars that exist throughout the Universe. The largest and most luminous of the red giant stars are some 50 billion times brighter than the coolest red stars (none of which can be seen without a telescope), though they all have effective temperatures ranging from about 3900K (M0) down to 2600K (M8). Their spectra are littered with a maze of strong absorption lines, caused by the presence of simple molecules that absorb light in their tenuous, low gravity atmospheres, including substances such as TiO, CN, ZrO, C3, C2, and CO amongst others. Indeed, these substances collectively absorb so much light (particularly at shorter wavelengths) from their cores, that astronomers have found them difficult to classify in a coherent way. This is because it can often prove exceedingly difficult to trace out their black body curves, in a way that their basic properties can be inferred like hotter stars can.

Red giant stars that have evolved off the main sequence exhibit substantial mass loss in the form of powerful stellar winds and thermal pulses which expel layers of their outer atmospheres to the cold, dark of interstellar space. Cool, dwarf stars, on the other hand, have hardly changed since their birth, and are so parsimonious in their energy generation that they can continue to exist stably for a trillion years or more. And while highly evolved red giant stars are not considered likely candidates for life bearing planets, there has been quite a lot of attention paid to the environments around cool, red dwarf stars, as locations that might harbour viable life bearing worlds.

Doubtless the interested reader may have heard of recent discoveries made by astronomers in regard to a string of planets orbiting close to M dwarf stars. One example widely cited in the media is TRAPPIST-1, located 39.5 light years in the constellation Aquarius. A media frenzy ensued when the team of astronomers monitoring the system announced a cache of seven worlds orbiting the star, all of which  were deduced to have broadly Earth sized masses. The scientists, keen to maximise the impact of their work (thereby securing more funds), stressed the observation that three of these planets lie within the water habitable zone (one of several other ‘habitable zones’ that the scientific community need to talk about, openly and honestly) of TRAPPIST-1 and so could conceivably host some kind of life. But it’s always worth taking a closer look at these planets before jumping to sensationalised conclusions.

Three of these TRAPPIST-1 worlds (designated b, c and d) are of particular interest to astronomers, lying just 1.66, 2.28 and 3.14 million kilometres, respectively, from the dwarf red star’s surface. This means that they will be tidally locked to their star and thus will always show the same face to it as they move in their orbits.This creates potentially enormous differences in the temperatures of the day and night sides of the planets, which doesn’t bode well for life. They are also sufficiently massive and close to each other to exert periodic gravitational influences on one another. These induced perturbations likely rule out the possibility of life on these planets, since it would destabilise and frustrate the travails of any emergent lifeforms on these worlds.

Compounding these difficulties is the physical properties of these dwarf stars. Though only 8 per cent the mass of the Sun, recent XMM Newton observations showed its emission of X rays is comparable to that of the Sun and, owing to their very close proximity to TRAPPIST-1, the resulting X ray irradiance would likely strip away any primordial atmospheres they might have had. Then, to add insult to injury, many of these stars exhibit strong stellar winds, especially in their younger days, when they were engaged in the nurturing of planetary systems. This would require the planets to possess magnetic fields several times stronger than that of the Earth in order to stave off the certain extirpation of any putative lifeforms on their surfaces.

In short, when these physical parameters are factored into the discussion, one can begin to see the unbridled speculation of science journalists shining through. Whether it be the BBC, CNN, or from popular astronomy periodicals, can you not see that they are all hewn from the same stone? They make wild claims that have no basis in a grounded scientific assessment (and the project scientists often make no mention of them which is very telling, in and of itself). Once again, many folk, with their misplaced commitment to methodological naturalism, are only all too willing to give their sovereignty away. What a pitiable state of affairs!

I for one feel most very fortunate indeed to be able to observe the red stars from my back garden, on terra firma!

Update 23.03.17: Still more problems attending the TRAPPIST-1 system, as more detailed 3D climate modelling is done on the planets in this system. Details here.

 

 

Neil English is author of several books on astronomy and is currently writing a largely historical work, Tales from the Golden Age of Astronomy, chronicling the great achievements of historical astronomers over the past four centuries.

 

De Fideli.

 

 

Tales from the Golden Age: Angelo Secchi: Father of Modern Astrophysics.

Angelo Secchi(1818-1878), pioneer of stellar spectroscopy. Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Do the words of a poem lose their poignancy once its author departs this world?

Can the limp of ‘progress’ outshine the ‘grand procession’ of great accomplishment?

Can a culture, basking in the glory of its own achievement, be made mute by a faithless generation of technocrats?

Can an optical bench test inspire more than a night spent behind the eyepiece of a grand old telescope?

Let us venerate that which is deserving of veneration!

Whose crown shall we adorn with a laurel wreath?

Let us sing again of old dead men

 And clear the cobwebs from their medals.

For they have no equal in the present age

No muse to light their way.

 

The Napoleonic era, which formally ended at the Congress of Vienna in 1815, brought sweeping social and political changes across Europe. Traditional values and beliefs were being questioned, as a new wave of libertarian ideas swept through Britain, France and the Italian peninsula. Politically though, the old, pre-Napoleonic status quo was once again established and for Italy, this meant Austria once again administered various states within its borders, including Lombardy and Venice. The Savoy-ruled Kingdom of Sardinia recovered Nice, Piedmont, Savoy and Genoa, an important stepping stone on the journey to unify Italy, in a movement the nationalists called ‘Risorgimento’. The large division of wealth between the north and south of the Italian peninsula led to rapid urbanisation and industrialisation in the former, while the latter was still poor, supporting a largely underdeveloped, agrarian lifestyle.  The Papal States, which occupied central Italy and the Spanish dominated Kingdom of the Two Sicilies, administered from Naples, ruled much of southern Italy, as well as the island of Sicily.

It was into this politically turbulent world that Pietro Angelo Secchi was born to middle class parents, Antonio Secchi, a joiner, and mother, Luise Belgieri, in the small city of Regio Emillia on June 18 1818. Just a few years before, in the aftermath of the Treaty of Vienna Reggio was returned to Francis IV d’Este, Duke of Modena, but in 1831 a revolt rose up against him, and as a consequence, Reggio proclaimed its union with Piedmont. Despite these sweeping changes, young Angelo showed great academic promise and his parents sent him to the local gymnasium, run by the Jesuits, where he received an excellent secondary education, feeding his great passion for physical science. On November 3 1833, the teenage Secchi enrolled in the Jesuit Order in Rome. Here he continued his education in the humanities, theology and philosophy but thoroughly excelled at mathematics and physics, so much so that by the age of 22 he was appointed tutor in physical science at the Roman College, becoming a full professor (though still without a doctorate) at the Jesuit College in Loretto by 1841. Despite his great gift in scientific matters, he endeavoured not to neglect his theological studies, and was ordained a priest in 1847.

But the security Secchi enjoyed as a young scientist and Roman Catholic priest was being eroded by fresh rumours of revolution. In 1831 Giuseppe Mazzini (1805-1872) founded the nationalist organisation, Young Italy, and by 1832 he unsuccessfully tried to induce mutiny within the Sardinian Army. Two years later another conspiracy against the Kingdom of Sardinia broke out but, once again, it ended in failure. During this desperate and politically uncertain times, Mazzini had gained considerable popularity all across Europe, so much so that he was nicknamed the ‘prophet of nationalism’. It was during the Revolution of 1848 that Mazzini finally had his day. This time, the well-organised revolt was eminently successful, with Mazzini taking his place as one of the founding fathers of the new but short lived ‘Roman Republic,’ which was to fall only a year later in 1849. The revolutionaries expressed a visceral hatred for the theocracy of the Papal States, headed by the pontiff, Pius IX (1792 –1878). Secchi, together with his Jesuit colleagues, was forced to leave Rome. He travelled to Paris and then made his way across the channel to England, where he took up residence at Stonyhurst College, Lancashire, for a few months. It was during his brief time in England that Secchi lost his close friend and fellow astronomer, Francesco de Vico (1805-1848), discoverer of no less than six comets during his brief career, who sadly succumbed to an aggressive bout of typhus fever in London.

On October 24, 1848, Secchi, together with twenty other exiled Jesuits, embarked on a month–long journey across the Atlantic, setting sail from Liverpool to the United States. Here he was to link up with a one Father Curley, who directed the Jesuit College at Georgetown, District of Columbia. Here he submitted and brilliantly defended his doctoral thesis and was shortly thereafter offered the post of Professor of Physics. As of yet, astronomy did not especially captivate the young scientist, but that was all about to change when he stoked a friendship with the distinguished American astronomer, maritime scientist and meteorologist, Commodore Matthew Fontaine Maury (1806– 1873), who was serving as the superintendent of the newly established US Naval Observatory in Washington. There, Secchi published his first paper in experimental physics; on the measurement of electrical resistance and its application to telegraphy. But Secchi’s stay in the New World was to be equally short lived, when Pius IX ordered their return to Rome after the French general, Charles Odinout, terminated the Roman Republic in the summer of 1849, on the proviso that he grant religious freedom to his subjects as well as the installation of a secular government. Indeed, it was French forces that propped up Pius IX’s administration in Rome right up until the outbreak of the Franco-Prussian War in 1870.

Pope Pius IX as a young man. Image credit: Wiki Commons.

Anecdotally, Pope Pius IX was known for his resistance to liberalism, socialism and the separation of church and state. As the longest reigning pontiff in the history of the Roman See, he was the first to sanction the perennially controversial notion of ‘papal infallibility’, as well as the elevation of Mary, the mother of Jesus, to ‘Mediatrix’ between God and man, at the first Vatican Council (1869–70), but was eventually cut short owing to the loss of the Papal States. It would be entirely wrong however to claim that he was not a cultured man. Indeed, Pius IX was a notable patron to the religious arts, but also cultivated a keen interest in the sciences, particularly astronomy. Indeed, in his youth, Pius IX had taken science courses at Scolpian College, where he apparently submitted a detailed dissertation ‘on the construction of telescopes’.

The Roman See, of course, was no stranger to the value of practical astronomy, but in the aftermath of the revolutionary years of 1848 through 1849, Pius IX was determined to set Vatican astronomical research on a new course; viz a viz, as champion of the new science of astrophysics. Indeed, it was shortly after Pius IX’s return to Rome in the spring of 1850 that he appointed Father Angelo Secchi to head the leading pontifical observatory at the Collegio Romano. It was an opportunity he found too good to refuse.

Observatory of the Roman College. 1 – Main Observatory of equatorial Merz telescope. 2 – Main staircase to the Observatory. 3 – Observatory elliptical meridian circle of Ertel. 4 – Observatory for the telescope of Cauchoix. 5 – Observatory electric tower with small lead ball. 6 – Antenna with globe dropped at midday as signal to fire the cannon at Castel Sant’Angelo (now on the Janiculum). 7 – Electric cables transmit signals from meteorological sensors on Calandrelli Tower to meteorograf recorder housed in room below main observatory. 8 – Rear of St. Ignatius facade. 9 – Back of Church of St. Ignatius. 11 – Tower Terrace. 12 – Roof of Palazzo Montecitorio, now the Chamber of Deputies. Image credit: Wiki Commons.

Thanks to generous private donations and direct papal support, Secchi set about building a state of the art observatory. He chose a very symbolic site for the new cathedral, dedicated to the starry heaven, the roof of the church of St. Ignatius at the Collegio Romano, set immediately above a series of imposing columns originally built to accommodate an enormous 18 metre diameter dome, but which never saw the light of day. Instead of crucifixes and statues dedicated to the saints of the Roman Catholic Church, Secchi would adorn the building with the finest telescopes and experimental electric and magnetic devices money could buy. And, all the more remarkably, he completed the construction of the building in just one year!

The 24.5cm Merz equatorial refractor near the time of its establishment at Collegio Romana. Image credit: Wiki Commons.

The centre piece of the new observatory was a fine, equatorially mounted refractor, with an aperture of 24.5cm and a focal length of 430cm (so f/17.6), built by the Bavarian optician, Georg Merz (1793–1867), who superseded Joseph von Fraunhofer as director of his famous optical business in the event of his untimely death in 1826.The instrument was the largest of its kind in Italy when it was finally dedicated in 1853, and truly emblematic of the fresh confidence bestowed upon a new breed of Vatican astronomers, connecting the earth with the wider creation. As well as the large Merz refractor, Secchi, at the behest of Pius IX, also installed an elaborate meridian circle for the express purposes of synchronising all national clocks to the Roman meridian time line. And though the Roman people were largely ignorant of the goings on inside the new Osservatorio Pontificio, they were at least grateful to the clerical astronomers for providing them with the precise time of day. The adjacent rooms leading off from the observatory were lavishly equipped with cutting edge electromagnetic gadgetry,to investigate terrestrial and solar magnetism, as well as a state of the art meteorological laboratory. A smaller Cauchoix refractor, with an aperture of 16.3cm, was also dedicated to observations of the Sun.

Secchi’s earliest discoveries in astronomy included the discovery of three new comets between the years 1852 and 1853. A decade later, he was to wade into the debate concerning the nature of fountain like jets that were seen streaming from the starlike nucleus of Comet 1862 III, proposing his fountain model to explain their nature. In effect, the jets emanating from the nucleus, in Secchi’s opinion, derived from heating of the nucleus by the Sun’s rays, the sublimating material being ejected as streamers much in the same way as geysers or water fountains.

Because the Merz equatorial was fully the equivalent of the great Dorpat refractor erected in Russia, and employed by the noted German born double star observer F.G. Wilhelm Struve(1793–1864), Secchi felt it appropriate to initiate his astronomical researches with a thorough revision of his great catalogue of double stars compiled between the years 1824 and 1837. This was very exacting work that required a lot of mental concentration, but like all true science, Secchi felt that Struve’s work had to be confirmed by direct observations and measurements. After a gruelling seven year program of micrometer work at the telescope, conducted on every clear evening, Secchi was able to present the chief portion of his results in a work entitled, “Memorie del Collegio Romano” published in Rome in 1859, which contained measures of some 10,000 verified double stars. This work was later continued by his assistants in 1868 through 1875, the results of which were published in two further supplements. Indeed, the later double star astronomer, Dr. William Doberck (1852-1941), extensively leaned on Secchi’s catalogue (as well as other historical measures) in deriving many of his orbital calculations.

Secchi carried out many routine observations of the planets, particularly Mars, Jupiter and Saturn, the great telescope producing beautiful and highly detailed drawings of these worlds in the tranquil Roman air. He conducted accurate micrometer measures of the size of the Jovian disk and identified essentially all of the features in the planet’s atmosphere that are enjoyed by modern medium aperture telescopes, including many of the belts and zones, ovals, barges, as well as the Great Red Spot (or ‘hollow’ as it was then known), and speculated on whether the asymmetry he observed in the equatorial bands provided any deeper clues as to the nature of this giant planet. He also studied the kinematics of Jupiter’s four large moons. He also produced, through detailed observations with the 24.5cm Merz, a highly detailed map of the great lunar crater, Copernicus.

Secchi conducted many detailed observations of Mars with the 24.5cm Merz refractor, identifying the dark areas as extensive ‘seas’ and the lighter areas as ‘deserts,’ much in the tradition of his contemporaries. And while many historians of the planet Mars attribute the origin of the concept of ‘canali’ to the ruminations of G.V. Schiaparelli, it was actually an idea coined by Secchi’s fecund mind, and who indeed recorded canal like structures on the planet’s surface though they were not as ‘linearized’ as those depicted by his Milanese compatriot. Secchi’s theology; which still seems little differentiated from the contemporary Jesuit astronomers; took him far beyond the authority of the Bible, and allowed him to openly accept that ‘reality’ of the plurality of habitable worlds:

In our opinion, “Secchi wrote, “it seems absurd to regard the vast regions [of the Universe] as hardly inhabited deserts; rather, they must be richly populated with beings intelligent and rational, capable of knowing, honouring and loving their Creator.”

Such unbridled speculation was typical of men of his day, but, as modern science is continually revealing (or rather not revealing!) the question of the ‘inevitability’ of life on other worlds is not at all as certain as it seemed only a few decades ago. Nor had he any idea of just how astonishingly complex even the simplest living systems are. One cannot help but wonder whether Father Secchi might ever have read or contemplated the view of the Hebrew psalmist, who long ago declared that we “are fearfully and wonderfully made” (Psalm 139:14).

Much of Secchi’s work on planetary astronomy may be consulted in his highly influential 1859 publication, “Il quadro fisico del sistema solare secondo le pill recenti osservazioni“.

Secchi developed a particularly intense interest in solar astronomy, employing the 16.4 cm Cauchoix refractor to make daily drawings of the white light solar disk. Any interesting sunspots, faculae and prominences were scrutinised very closely and recorded with exquisitely fine drawings made at the telescope. Secchi, together with some of his research assistants transported the Cauchoix refractor to Spain to observe the total solar eclipse of July 18, 1860, where he was to photograph the solar corona and prominences thereby silencing any sceptics who had previously claimed that such phenomena were entirely illusory and/or were associated with some kind of lunar structure. Just one month later, Secchi was electrified to hear of the progress of Pierre Jules Janssen (and independently by Sir Norman Lockyer in England), who had manipulated the spectroscope to observe such prominences during broad daylight. Indeed, it was the spectroscope that enabled Secchi to make his unique mark in stellar astrophysics; by convincingly demonstrating that not all stars have the same composition.

On his return from the expedition to Spain, Secchi commissioned the instrument makers Hoffmann and Merz to build special spectroscopes with multiple prisms, as well as an ingenious objective prism that would enable him to observe multiple stellar spectra simultaneously. When coupled to the long, native focal length of his observatory refractors, he was able to obtain images of sufficiently large image scale to study these spectra quite well through entirely visual means! This epochal work began in 1862 and culminated five years later in 1867 with a stellar classification scheme including more than 4,000 stars, which he divided into five distinct categories:

Type I: appearing white or blue white through the telescope, characterised by broad, heavy hydrogen lines. A subclass showed narrower lines. This type includes the modern class A , B and early class F. These include familiar luminaries such as, Vega, Rigel and Altair.

Type II: the yellow stars showing weakened hydrogen lines, but with the addition of metallic lines. This type includes what astronomers recognise today as late class F, G and K stars.

Type III: Looking orange or red to the eye, these show complex band spectra, and include familiar stars like Betelgeuse and Antares. Secchi’s third type corresponds to the modern class M stellar category.

Type IV: The intensely red stars (C and M class subtype), with strong absorption lines owing to carbon and its simpler molecules. Secchi was mesmerized by this class of star as they showed very clear differences in chemical composition to the earlier types. So taken was he by the beautiful appearance of the spectrum of one member, Y Canum Venaticorum, that he nicknamed it La Superba, a time honoured moniker among astronomers.

Type V: these show strong emission lines and include γ Cassiopeiae and β Lyrae.

See here to view Secchi’s stellar classes.

It is all the more remarkable that Secchi achieved so much given the fact that the objective prism he employed with the Merz equatorial effectively reduced its aperture to about half of its working diameter (so about 5 inches in reality)! Furthermore, the significant additional mass incurred in carrying the prism led to problems with the tracking of the equatorial mount, which would have undoubtedly frustrated any efforts made to record those faint spectra.

It is also easy to underestimate the achievements of Secchi in providing the first break down of the various stellar classes of stars, for it represented the first step toward understanding how stars evolve in time. In 1865, the Leipzig based astronomer, Friedrich Zöllner (1834–1882) suggested that stars were first born hot, and, as they naturally cooled, passed through the solar type to the more highly evolved red stars. However it was another Leipzig born astrophysicist, H.C Vogel (1841–1907), based at Potsdam Observatory, Germany, who greatly advanced the cause of stellar spectroscopy beyond the virginal efforts of Secchi.

Herman Carl Vogel (1841–1907). Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

Working in collaboration with the Swedish astronomer, Nils Christofer Dunér(1839—1914), who aslo employed a 24.5cm Merz achromatic refractor at Lund, he prepared catalogues of stellar spectra of tens of thousands of stars. It was Vogel’s classification scheme that led to the idea of an orderly evolutionary progression between the various star types; an idea that found its fullest expression in the Hertzsprung–Russell diagram, so central to modern stellar astrophysics.

The Hertzsprung–Russell diagram of stellar evolution. Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Secchi had reached the height of his career in the midst of social and political upheaval.  Italy’s unification was finally accomplished by the leadership of two men, Camillo Benso, Count of Cavour(1810–1861) and Giuseppe Garibaldi(1807–1882), but not without considerable help from foreign agencies. In 1858, Cavour brokered a deal with France. Specifically, Cavour, who administered Piedmont, agreed to bequeath France some of its territory in return for its military assistance in ousting the Austrian forces, who were controlling most of Italy at the time. Two years later, Garibaldi raised a volunteer army to complete the cause of Italian unity.  He conquered much of Southern Italy in a bloody civil war, after which time Cavour’s armies were amalgamated with his own forces, pacifying much of the peninsula and establishing the country of Italy in 1861. The final cementing of Italian unity came from the aid of Prussia, which formed a military alliance with Italy in the wars of 1866 and 1870, defeating France and Austria and ordering the expulsions of all their politicians and administrators by 1870. Italy as we now know it, was finally born, and with it, came the dissolution of the papal states.

From the outset, the new Italian government was keen to foment its newfound unity in all matters, including science and technology. Accordingly, Secchi was invited to accompany a team of astronomers, physicists and technicians from all over Italy to observe the total solar eclipse from the island of Sicily, which was to take place on December 22, 1870. The expedition was to include scientists from Rome, Florence, Naples, Padua and Palermo, the capital of Sicily. Intriguingly, Secchi, though eminently qualified to do so, was not given any overarching authority over the rest of the scientific team, perhaps, as some scholars have suggested, to express the egalitarian values of the ‘New Order’ That said, Father Secchi, in the true spirit of open scientific enquiry, enthusiastically agreed to go.

This was by far the most ambitious and centrally organised scientific endeavour ever mounted by the newly minted Italian nation. But it was not without its perils; the Italian army had to accompany the scientists as they transported their telescopes, chronographs and photographic plates across the island, all the while wielding the new national flag, as hostility was expected from the islanders who, as recently as 1866, had mounted an anti–Italian insurrection. They were also accompanied by independent British and American expeditions, headed by Sir Norman Lockyer and Professor Charles Augustus Young, respectively.  The scientific program included visual and spectroscopic observations of the solar corona and prominences, with Secchi overseeing the photographic projects. Though the weather proved to be rather cloudy and the photographs turning out poor during the course of the eclipse, Secchi was able to obtain spectral evidence of an entirely new solar phenomenon known as a flash spectrum, immediately above the photosphere, which was also confirmed by the American astronomers.

Secchi was keen to standardise the observations of all the Italian observers and, having set up a small Merz refractor in situ, instructed them to take their turns making visual sketches of the prominences they saw at the eyepiece. The learned Padre was apparenty quite taken aback by the large variations exhibited in their drawings. Some saw things that were apparently quite invisible to others, which only serves to endorse the old adage that a single trained eye is better than a dozen untrained ones!

Yet in other ways, Secchi was the instigator of exceptionally high standards in the co–ordination of astronomical observations.His working knowledge of electromagnetism enabled him to set up near simultaneous communications with his fellow astronomers across the continent of Europe in order to compare their observations with those made on Sicily. Indeed, over the next few years, together with his friend and fellow astronomer, Pietro Tacchini (1838–1905), he established an elaborate observation network with other Italian astronomers so that they could compare spectroscopic analyses of the Sun at almost the same time every day. Indeed Secchi’s standardisation methods were soon adopted by all major centres of international astronomy. It was Tacchini’s loyalty to Secchi that probably secured his future appointment as the Director of Research at the Observatorio del Collegio Romano after Secchi’s passing.

Secchi’s intense researches into the physics of the Sun provided us with an essentially modern conception of the makeup of our star. Perhaps more clearly than anyone who ever lived before him, Secchi understood that the Sun is a star like myriad others that grace the cosmos. He believed that sunspots were regions of increased magnetic activity and that the various prominences he observed on the solar limb influenced terrestrial weather. He also correctly deduced the gross structure of the Sun, with a superhot and dense core overlayed by a progressively cooler gaseous atmosphere. His influential solar monograph summarising his ideas, Le Soleil, was first published in Paris in 1870, followed up by a German translation which first appeared in 1872 and was followed up with a second French edition appearing in 1875.

Secchi believed the Earth and the Universe to be  very old; tens of millions of years, if not more. This seemed to be endorsed by new theoretical work conducted by some of the finest theorists of his age, particularly William Thomson (Lord Kelvin) (1824–1907) and Hermann von Helmholtz (1821–1894), who had proposed a mechanism of slow gravitational contraction as the process that powered the Sun over these timescales. And though this was superceded by the theory of thermonuclear fusion in the 20th century, it is still a vaild process in the formation of protostars, as well as the evolution of ageing stars off the main sequence into giants. Collectively, these new scientific revelations served only to deepen Secchi’s faith in a great Creator God, who upheld the workings of a unified Universe, with all its matter and motion, through His Logos.

In the closing years of his life, his devotion to the Jesuit Order in general, and to the Holy Father in particular, continued to cause tensions with the secular Italian government, which had placed restrictions on Jesuit teachings and research in Rome and farther afield. Secchi was offered the chair in physical astronomy at the University of Rome, which initially he accepted, on the condition that the Jesuits be allowed to continue their ambitious program of education and scientific research. When they refused, Secchi withdrew his offer. By 1872, the Italian government formally protested against Secchi’s representing the Roman Catholic Church at the prestigious Commission Internationale du Metre held in Paris, which they evidently saw as confusing the role of church and state. In 1873, the Collegio Romano was declared the official property of the Italian government. And by 1874, to add insult to injury, the same government severed all ties with Secchi by despatching a team of Italian astronomers to India to observe the transit of Venus entirely without his consultation. It was a bitter blow to the diligent Jesuit scientist, who had doggedly refused to pledge his allegiance to the new nation instead of the Pope. Over the next few years, his health gradually failed and eventually he succumbed to a mystery stomach ailment on February 26 1878, aged 59 years;and less than three weeks after his great patron, Pius IX, passed away.

Bust of Angelo Secchi by Giuseppe Prinzi as it appears in the gardens of the Pincio Hill, Rome. Image credit: Lalupa.

 

 

 

 

 

 

 

 

 

 

Secchi received many honours from fellow astronomers outside Italy. He was elected to England’s prestigious Royal Society and Royal Astronomical Society, the French Académie des Sciences, as well as Russia’s Imperial Academy of St. Petersburg. A lunar and Martian crater were also named in his honour, as well as the asteroid 4705 Secchi, residing in the main belt. Outside the sphere of astronomy, Secchi’s name is associated with many other fields of scientific enquiry. One example is the Secchi disk, a simple device devised by him in 1865, which is used to assess the turbidity of sea and fresh water reservoirs. The disk, which has a diameter of 30 cm, is usually mounted on a pole or line, and slowly lowered down into the water. The depth at which the disk is no longer visible is taken as a measure of the transparency of the water. Such an ingenious device was first used by oceanographers in the Mediterranean Sea, but nowadays it is employed almost universally in slightly different forms.

As father of modern astrophysics, Secchi’s legacy was carried into the 21st century when the Solar Terrestrial Relations Observatory (STEREO), which entered orbit in 2006, carried on board a suite of instruments known collectively as the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI), in remebrance of the great 19th century Italian astronomer. Finally, it is worth noting that Secchi founded a dynasty of Jesuit astronomers that continue to bring the heavens closer to the earth, even to this day.

Dr. Neil English is writing a book entitled, Tales from the Golden Age of Astronomy, which honours the singular achievements of ancestral observers who often employed very modest equipment to push back the envelope of human knowledge about the cosmos.

De Fideli.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

A Modern Commentary on W.F. Denning’s “Telescopic Work for Starlight Evenings” [1891] Part II

Octavius; the authors 8" f/6 Newtonian Reflector

Octavius; the author’s 8″ f/6 Newtonian Reflector.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Continued from Part I

 

Chapter IX Mars

Covering pages 155-166

Mars is the fourth planet in order of distance from the Sun. He revolves in an orbit outside that of the Earth, and is the smallest of the superior planets. His brilliancy is sometimes considerable when he occupies a position near to the Earth, and he emits an intense red light, which renders his appearance all the more striking. Ordinarily his lustre does not equal that of Jupiter, though when favourably placed he becomes a worthy rival of that orb. In 1719 he shone so brightly and with such a fiery aspect as to cause a panic. The superstitious notions and belief in astrological influences prevailing at that time no doubt gave rise to the popular apprehension that the ruddy star was an omen of disaster, and thus it was regarded with feelings of terror. Fortunately the light of science has long since removed such ideas from amongst us, and celestial objects, in all their various forms, are contemplated without misgiving. They are rather welcomed as affording the means of advancing our knowledge of God’s wonderful works as displayed in the heavens.

pp 155

In line with previous chapters, Mr. Denning summarises the main physical data associated with the Red Planet, which is essentially modern. Mars can vary enormously in its apparent size, from 4″ when it is near conjunction with the Sun, and swelling to over 30 seconds of arc at opposition. It has been known since the time of Galileo that Mars can present with a prominent gibbous phase. When it is furthest from the earth, Denning reminds us that it is only large, observatory class telescopes can make out any significant details on the Mars, but as it approaches opposition it can become a ‘magnificent object’ worthy of telescopic scrutiny. He advises that meaningful observations conducted by amateurs should really only be done in the weeks leading up to and following opposition.

Denning is clearly aware that the Martian atmosphere is very rarefied in comparison to our own world and thus its surface features are relatively easy to delineate in a modest telescope. The discussion then develops with a mention of some seminal historic observations conducted by his astronomical forebears, most notable of which are Fontana, Cassini and Huygens, who came up with pretty astonishing measures of the rotation period of the planet (now called a sol), which demonstrated that a Martian day was only a little longer than the Earth.

Denning mentions the intense white patches seen at the planet’s poles but still cautions to call them “polar snows.” A drawing of the planet as it appeared to Denning on the evening of April 13 1836 appears on page 157 using his 10-inch Newtonian, power 252x.

On page 158 of the text, Mr. Denning describes the long tradition of Martian map-making, that is, aerography, conducted by many of his diligent predecessors, including the work of Maraldi, Herschel, Schroter, Madler, Schmidt and Dawes, whose named adorned the earliest martian maps available to amateur astronomers. Darker regions were almost invariably associated with ‘seas,’ and the brighter sections, ‘continents,’ indicating that these early telescopists were keen to impress a sense of the familiar to the planetary images they studied with their instruments.

By the time he was penning the words of this text (c1890), Denning humorously quips that the naming of new Martian features had been reduced to the level of farce:

A few years ago, when christening celestial formations was more in fashion than it is now, a man simply had to use a telescope for an evening or two on Mars or the Moon, and spice the relation of his seeings with something in the way of novelty, when his name would be pretty certainly attached to an object and hung in the heavens for all time! A writer in the ‘Astronomical Register’ for January 1879 humorously suggested that “the matter should be put into the hands of an advertizing agent” and “made the means of raising a revenue for astronomical purposes.” Some men would not object to pay handsomely for the distinction of having their names applied to the seas and continents of Mars or to the craters of the Moon.

pp 158-9

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Author’s note: How ironic!  Denning was almost prophetic about the “cash for names” culture that would grow up in modern times. No need for the learned astronomer; one can now purchase one’s own star. My eldest son had a star named after him – a well meaning gift from a friend – though he wasn’t too impressed when he saw it through a telescope!

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On pages 159 through 160, Mr. Denning discusses the ‘recent’ discovery of the two diminutive satellites of Mars discovered by Professor Asaph Hall using the 25.8 inch Washington refractor in 1877. These eluded the eye of both Sir William Herschel, who undoubtedly used large enough instruments to detect them, as well as the astronomers who used the great 72-inch Leviathan of Parsonstown. Denning doesn’t provide any real explanations for this anomaly but may well have been attributed to the fact that the great refractor was mounted on a state-of-the-art, clock-driven equatorial mount, which helped to stabilise the images of the planet from moment to moment and was most ably suited to studying images for prolonged periods.

Denning also discusses the interesting phenomenon of the Martian “canals” [Denning’s emphasis] as observed by G.V. Schiaparelli beginning in the winter of 1881, together with their evolution into ‘duple’ structures by the summer of 1890.  Curiously, while Denning does mention a few other individuals who saw the canals, he himself does not emphatically admit seeing such structures (see page 160). Perhaps the most illuminating confirmation of the Martian canals comes from Denning’s compatriot, the lawyer and amateur planetary observer, A. Stanley Williams of Brighton, who recorded no less than 43 such structures, seven of which were clearly double, and all using only a 6.5 inch Calver reflector using powers between 320 and 430, though magnifications below 300 were deemed useless.

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Author’s note: That Williams was able to employ powers of and in excess of 50x per inch of aperture using his 6.5 inch Calver bears some testimony to the underlying quality of its optics; a point well borne out by my discussions with a few contemporary observers ( see a commentary on a 10-inch instrument about three fifths the way down Part I for an example) who have restored such instruments to functional use.

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Having said all that, Denning does provide his recommendations concerning the size of telescope that will provide fine, high magnification details of the Red Planet under favourable conditions;

Rather a high power must be employed – certainly more than 200; and if the telescope  has an aperture of at least 8 inches, the observer will be sure to discern a considerable extent of detail.

pp 162-3

Denning divides Martian surface phenomena into a number of categories:

  1. Seas; which he defines as dark areas, some of which can be picked up with apertures as small as 1.5 inches. He mentions the excellent work of Charles Grover, who started his career with very small instruments (see page 160).
  2.  Lighter areas that surround the ‘seas’ which can extend for hundreds of miles.
  3. Irregular streaks, condensations and veins, which, to some degree or other may appear linear. He does suggest however that on a night of good seeing, these linear structures resolve into ‘spots’ (page 161).
  4.  Atmospheric features owing to Mars’ thin but still appreciable sea of air, some of which can be traced right the way to the limbs of the planet.

Denning presents still more invaluable information concerning measures of the rotation period of the Red Planet as estimated by a dozen or so astronomers dating from the mid-17th century. Although all of these estimates are very accurate, it is curious that Sir William Herschel got closest to the modern accepted value as early as 1784, a full century before Denning penned this work. He includes his own value of 24 hours, 37 minutes and 22.34 seconds reduced from data collated from 15 years of observations made from his home in Bristol[see footnote on page 162]!

The remainder of this interesting chapter covers some historical sightings of the satellites of Mars- Deimos and Phobos. Denning notes that no sooner had Asaph Hall discovered them with the 25.8 inch Washington Refractor that a suite of other sightings were reported using much smaller instruments; some as diminutive as 7.3 inches! This seems all the more incredulous considering that at greatest elongation from the planet, Phobos and Deimos shine feebly at magnitudes +11.5 and +13.5, and are separated from the Martian limb by a mere 12″ and 32″, respectively.

Finally, Denning mentions some notable historic occultations of Mars on page 166.

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Author’s note: The 165km-wide Martian crater, Denning, located  at 17.7° south latitude and 326.6° west longitude in the Sinus Sabaeus quadrangle, has been named in honour of the great British observer;

Denning Crater, Mars.

High resolution image of Denning Crater, Mars.

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Chapter X The Planetoids

Covering pages 167-169

In this very short chapter, Mr. Denning describes the state of affairs of asteroid discoveries made up until that time and their location, orbiting some 2-4 times further out from the Sun than the Earth, between the orbits of Mars and Jupiter. He recounts the elucidation of Ceres by Piazzi in 1801 and a few of the brighter asteroid discoveries in the decades that followed. Denning discloses that at the time of writing (c.1890), some 300 planetoids had been discovered at a rate of about six per annum, though many more were yet to be discovered. The largest and brightest of these are visible in common, backyard telescopes but they are not the most exciting objects to observe owing to their diminutive size. Denning wisely suggests that on-going searches for asteroids be conducted by properly equipped observatory-class instruments.

On page168 Denning makes this interesting remark:

A real variation of light has been assumed to occur, but this is not fully proved.

pp 168

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Author’s note:  Denning alludes to the possibility that the asteroids vary in brightness. Today we know that asteroids rotate and thus display different surfaces to the sunlit side facing the Earth. These surfaces will often have differing albedos, thereby explaining the variation in brightness. Today, though astronomers estimate that millions of asteroids exist, only 60 or so have sizes larger than about 60 kilometres and about 750,000 have sizes of the order of 1 kilometre. Most of the asteroids uncovered during Denning’s lifetime were between magnitude 10 and 12. Asteroids are thought to represent the left over debris from the formation of the solar system, some 4.6 billion years ago.

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Chapter XI Jupiter

Covering pages 170-194

Of all the planets, Jupiter is the most interesting for study by the amateur. It is true that Saturn forms an exquisite object, and that his wonderful ring-system is well calculated  to incite admiration as a feature unique in the solar system. But when the two planets come to be repeatedly observed, and the charm of first impressions has worn away, the observer must admit that Jupiter, with his broad disk and constantly changing markings, affords the materials for prolonged study and sustained interest. With Saturn the case is different.His features are apparently quiescent; usually there are no definite spots upon the belts and rings. There is a sameness in the telescopic views; and this ultimately leads to a feeling of monotony, which causes the object to be neglected in favour of another where active changes are in visible progress.

pp 170

William Denning was arguably the most experienced observer in the world at the height of his astronomical career. Having clocked up thousands of hours conducting naked eye observations of meteors, scanning the sky for comets (of which he was the discoverer of five such bodies), and providing regular and highly detailed views of the planets, his opinions were well sought after by the best professional astronomers of the day. In regard to planets, it was arguably the giant world, Jupiter, that captivated his imagination most strongly, and for reasons he makes clear in the opening paragraph of the chapter quoted above. It is therefore no small wonder that he dedicated 24 pages to its study.

Denning’s renderings of Jove were referenced in every authoritative work on the planet over the past century. For serious work on Jupiter, Denning used his 10-inch silver-on-glass reflector, the drawings from which were widely disseminated in the popular publications of the day. These and other archives show that he employed the same instrument to continue his Jupiter studies for a full decade after he penned his magnum opus.

Denning’s interest in Jupiter appeared to be mostly scientific in nature. As we have seen with the other planets, he spent long hours making estimates of the rotation of these bodies, Jupiter included. But in making such observations, he picked up many fine details of this complex and rapidly changing world, the characteristics of which have been confirmed to exist in the modern age.

After describing the various belts and zones that can be seen though a good telescope, Denning, as usual, never fails to acknowledge the outstanding work of his forebears in establishing many of the basic facts often taken for granted by his contemporaries [and his descendants too]. On page 172, he mentions that the earliest detection of distinct belts girdling the planet was made by “Zucchi” as early as 1630. Undoubtedly, Denning was referring to the Italian Jesuit priest and astronomer, Niccolo Zucchi(1586-1670), who made many important contributions to the science of optics, even proposing that concave mirrors could replace lenses to focus light as early as 1616 (these and other topics are discussed at much greater length in the author’s up and coming book, Tales from the Golden Age of Astronomy).

It was astronomers such as Robert Hooke and G.D. Cassini, using the long focus non-achromatic refractor, who were amongst the first to see definite spots on the planet, allowing them to make good estimates of Jupiter’s rotation period. Denning informs us that it was Cassini who first noted that spots located at different Jovian latitudes appeared to rotate at different degrees of celerity; the higher the latitude the slower the rate of rotation. Cassini measured this discrepancy to about 6 minutes, while Sir William Herschel, observing a century later, whittled it down to nearer 5 minutes.

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Author’s note: the phenomenon of differential rotation, that is, when different parts of a body rotate at different rates, is indicative of the non-solid makeup of the body under study and can readily be observed by amateur telescopes on the Sun, Jupiter and Saturn. Differential rotation is the reason why Jupiter observers acknowledge different systems of longitude on the planet: System I, which defines the longitude of the equatorial region, rotates at a rate of 9 h 50min and 30.003 seconds, while System II longitude, covering the higher latitudes (both north and south), has a period of 9h 55 min and 40.6 seconds.

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Beginning at the bottom of page 173 and continuing through to 175, Denning engages in a fascinating discussion on arguably Jupiter’s most interesting phenomenon; the Great Red Spot. He describes how this enormous elliptical shaped feature has changed dramatically in size and colour intensity over the years (as evidenced by many of his own superlative drawings of the Jovian disk). During the late 19th century, the spot was enormous;

From measures at Chicago, in the years 1879 to 1884, Prof. Hough found that the mean dimensions of the spot to be:- Length 11″.75, breadth 3″.71. these figures represent a real length of 25,900 miles and a diameter of 8200 miles. The latitude of the spot was 6″.97S

pp 174

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Author’s note: What invaluable information we have here! How else might we obtain such knowledge?  The Great Red Spot has been shrinking throughout the 20th century. During NASA’s Voyager spacecraft flybys in 1979, it had a major axis of 14,500 miles and a Hubble Space Telescope measure made in 1995, showed it to be only 13,020 miles across. Finally in 2009, it had shrink still further to just 11,130 miles. My own telescopic observations over the years have also confirmed that it is both decreasing in size as well as rapidly losing its elliptical shape, and is more circular than it has been in living memory. No one knows precisely why this is the case, but since we do know it is a massive storm system, it must lose energy as it ages and thus, we may be witnessing its slow demise. Is the Giant Planet in the process of losing its most iconic telescopic feature? Will it be visible to future generations? I wonder!

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Mr. Denning, like many of his contemporaries, used the Great Red Spot (GRS) to obtain estimates of the rotation period of Jupiter. On page 175 however, he does present some intriguing data which show significant changes in the GRS rotation rate.

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Author’s note: It is not at all clear whether Denning was altogether aware of the possibility that the GRS itself was not fixed in longitude, but in fact slowly drifts over time. The interested reader should consult the later work of Bertrand M. Peek, who, in his book, The Planet Jupiter; An Observer’s Handbook(1958) provides some excellent graphical data showing just how much the GRS has drifted in longitude over time (1851-1935) on page 153 of the text.

Because atmospheric features such as the GRS are not fixed in longitude, they cannot ultimately be relied upon to arrive at the best rotation period measures for the planet. Today planetary scientists have abandoned all such approaches, relying instead upon the rotation of the Jovian magnetosphere as the most reliable method of deriving the planet’s rotation period. This so-called System III method, presents a rotation period of 9h 55 min.

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After discussing the usual Jovian features such as spots, barges, belts and zones, Denning returns to the GRS and speculates on why, over the years, its colour intensity varied so much with the passing of the years. On page 179, he offers a fascinating, and, as far as this author is aware, unique explanation of his own:

My own opinion of the spot is that it represents an opening in the atmosphere of Jupiter, through which , in 1872-82, we saw the dense red vapours of his lower strata, if not his actual surface itself. Its lighter tint in recent years is probably due to the filling-in of the cavity by the encroachment of durable clouds in the vicinity.

pp 179

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Author’s note: Denning was incorrect about claiming to see the ‘surface’ of the planet. But his explanation of why the GRS varied in colour intensity is very imaginative and is at least scientifically plausible. In other literary sources we learn that Denning believed the spot to sink and soar periodically in the Jovian atmosphere, causing it to fade and intensify over time.  This idea has fallen out of favour with planetary scientists today however. Instead they propose that the brick red colour of the spot is due to the complex interactions of  cyano compounds with sunlight. Other researchers have implicated sulphur- and phosphorus-rich molecules upwelled from deep within the Jovian atmosphere.

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On page 178, he provides a plate of Jupiter drawings made by some of the finest British observers of Jupiter including Dawes, Huggins, Joseph Gledhill, as well as one presented by Denning himself. Curiously, the drawings show considerable detail that are broadly comparable between observers. Historically speaking, Dawes was in possession of a fine 7.5 inch Clark refractor at the time the drawing was recorded, Huggins employed a slightly larger 8.25 inch Clark object glass, and Gledhill probably used a similarly sized equatorial refractor to conduct his sketches(dated to 1870 and 1872).

Denning devotes the next few pages to discussions concerning other bright and dark equatorial spots and peculiar changes to the belt system of the planet as described by a variety of historically significant observers. This is followed by some general advice to the would-be student of the Giant planet:

Drawings of Jupiter obtained under the highest powers that may be employed with advantage, and with a cautious regard to faithful delineation, will probably throw much light on the phenomena occurring in the planet’s atmosphere. And it is most desirable  to pursue the various markings year after year with unflagging perseverance; for it is only by such means that we can hope to unravel the extraordinary problem which their visible behaviour offers for solution. Too much stress cannot possibly be laid on the necessity of the observers being as precise as possible in their records. The times when an object comes to the central meridian should invariably be noted; for this affords a clue to its longitude, and a means of determining its velocity. Its position N. and S. of the equator, should be either measured or estimated; and alterations in tone, figure or tint described, with a view to ascertain its real character.

pp 183

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Author’s note: a modern 8-10-inch reflector will show a wealth of detail on Jupiter, quite comparable to the drawings recorded on page 178 of Denning’s tome. Some of the finest contemporary renditions of Jupiter can be seen in the work of Dr. Paul Abel, an astronomer by profession, but also a keen amateur planetary observer, who uses an equatorially mounted 8-inch f/6 Newtonian to conduct all his superlative planetary drawings.

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In the remainder of this fascinating chapter, Mr. Denning extols the virtues of observing the many fascinating satellite phenomena associated with Jupiter. A table presented on page 188 gives some of the basic physical data of the Galilean satellites (abbreviated I to IV in order of distance from the planet). Their measured angular diameters (ranging from 0.91 to 1.49″) agree well with modern figures. What is more, they were all large enough for Denning to record them as discernible disks with his 10-inch With-Browning reflector, even when they are located to one side of the planet or the other.

Denning states that Sir William Herschel was amongst the first to observe differences in albedo in the Galilean satellites, particularly in observations carried out between 1794 and 1796. Denning attributes these differences to real surface features:

Spots exist on the surfaces of these objects, and probably occasion many of the differences observed.

pp 189

On page 193, Denning provides still more historical details of observers who recorded distinct markings on the Galilean satellites:

Spots have been seen on the satellites both in transit and while shining on the dark sky. This particularly refers to III and IV. II has never given indications of such markings on its bright uniformly clear surface. Dawes, Lassell and Secchi frequently observed  and drew spots. Secchi described III as similar in aspect to the mottled disk of Mars as seen in a small telescope; his drawings  exhibit no analogy, however, to those of Dawes of the same object. III. has been remarked as a curious shape, as if dark spots obliterated  part of the limbs. Sat I. was observed in transit on Sept. 8, 1890 by Barnard and Burnham, and it appeared to be double, being divided by a bright interval or belt. They used a 12-inch refractor, powers 500 and 700, and the seeing was very fine.

pp 193

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Author’s note: In retrospect, it is not at all surprising that surface details on satellite II were not forthcoming, owing to its diminutive size (0.91″) and its smooth ice-covered surface. Denning also notes the observations of E.E. Barnard and S.W. Burnham who were able to use powers of 500 and 700x on a 12-inch Clark refractor, providing further evidence of their optical prowess in sharp contradistinction to the prognostications of the ‘forum culture’ of the post-modern amateur, who has been blinded by his/her committment to materialism.

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Chapter XII Saturn

Covering pages 195-214

The globe of Saturn is surrounded by a system of highly reflective rings, giving to the planet a character of form which finds no parallel among the other orbs f our solar system. His peculiar construction is well calculated to be attractive in the highest degree to all those who take delight in viewing the wonders of the heavens. Saturn is justly considered one of the most charming pictures which the telescope unfolds. A person who for the first time beholds the planet, encircled in his rings and surrounded by his moons, can hardly subdue an exclamation of surprise and wonder at a spectacle as unique as it is magnificent. Even older observers, who again and again return to the contemplation of this remarkable orb, confess they do so unwearyingly, because they find no parallel elsewhere; the beautifully curving outline of the symmetrical image always retains its interest, and refreshes them with thoughts of the Divine Architect who framed it! The luminous system of rings attending this planet not only gratifies the eye but gives rise to entertaining speculations as to its origin, character, and purposes with regard to the globe of Saturn. Why, it has to be asked, was this planet alone endowed with so novel an appendage? And what particular design does it fulfil in the economy of Saturn? It cannot be regarded as simply an ornament in the firmament, but must subserve important ends, though these may not yet have been revealed to the eye of our understanding.

pp 195-6

In these opening lines of chapter 12, Mr. Denning lays bare the palpable sense of fascination with Saturn and its glorious ring system as revealed by the power of the telescope. The great telescopic observer had a very highly developed spiritual awareness of the created order of things made by the God of the Bible (he clearly identified himself as Christian). Denning clearly felt the Solar System was designed purposefully, to reflect the glory of its creator as well as to delight and stimulate the mind of man. And though Saturn’s rings may not have an obvious ‘purpose’ in maintaining the planet, they most certainly reveal something of the ‘Divine Architect’ who manifested them.

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Author’s note: The Solar System does indeed show remarkable evidence of design, such that of all the planetary systems characterised by astronomers to date, none is quite like our own. Advances in knowledge are revealing a remarkable sequence of events that shaped the formation of our planetary system in anticipation of the emergence of humankind. Though some men of science still vainly persist in entertaining the notion that there is nothing special about our predicament in space and time, there is no escaping the conclusion that we exist on this planet for a reason.

Denning was not aware that other planets exhibit ring systems albeit, very faint ones, including Jupiter and Uranus, which were not discovered until well into the age of robotic space exploration.

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One the great joys of reading older authors of astronomy is that they can provide brand-new insights and factual information that has been lost in the mists of time. As commented on previously, Denning was very meticulous in his presentation of historical information as introductory material for his chapters on visual observing. One gains the strong impression that he felt it right and honourable to note, albeit briefly, the achievements of those observers who came before him, and to include the comments of his contemporaries, even if they did not accord with his own.

For example, we all know that G.V. Cassini discovered the famous division in the ring system that bears his name. But can anyone inform me of the conditions under which he made these observations?

No?

I guessed not. Neither could I, incidentally, until this evening, that is.

You see, on page 198, we learn that the Cassini Division was discovered in twilight! And Denning tells us that he gets this information from Dr. Smith’s Optics (1738), who recounted the story thus:

In the year 1676, after Saturn had emerged from the Sun’s rays Sig. Cassini saw him in the morning twilight with a darkish belt upon his globe, parallel to the long axis of his ring as usual. But what was most remarkable, the broad side of the ring was bisected right round by a dark elliptical line, dividing it, as it were, into two rings, of which the inner ring appeared brighter than the other one, with nearly the like difference in brightness as between that of silver polished and unpolished- which, though never observed before, was seen many times after with tubes of 34 and 20 feet, and more evidently in twilight or moonlight than in a darker sky.

pp 198.

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Author’s note: Although this is ‘secondary source’ material, of course, it is nonetheless thrilling to ‘discover’ a historical morsel like this popping up in the pages of Denning’s tome. This author spends a considerable amount of time each year observing in twilight conditions, and enjoys finding things in twilight. He can also vouch that lunar and planetary images can look magnificent in twilight. Incidentally, as already mentioned, Denning was a keen observer by day and by night. Indeed, if the date of the Jupiter drawing made by Denning, and reproduced below, is correct, modern computer programs can show us that he must have observed it in a bright sky!

Denning's sketch of Jupiter dated February 13, 1888 showing the unusually large GRS and bright cloud within its confines. Source: http://www.phenomena.org.uk/page105/page131/page131.html

Denning’s sketch of Jupiter dated February 13, 1888 showing the unusually large GRS and bright cloud within its confines.
Source: http://www.phenomena.org.uk/page105/page131/page131.html

 

 

 

 

 

 

 

 

 

 

 

But to what extent, if anything, is Cassini’s assertion that his celebrated Division can be seen better in twilight? Is there any science to back that up?

Nescio.

It’d be cool to follow this up though,don’t you think, with experiments and the like.

Those ancient duffers eh, saving us from the dreaded brain rot, keeping the old grey matter ticking over!

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A Great Old Telescope: Dr. Jim Stephens, based in Mississippi, USA, kindly sent me a link to an antique With-Browning reflecting telescope, owned by Robert A. Garfinkle FRAS. The instrument, a 8-inch f/7.5 silver-on-glass speculum, was originally owned by Edmund Neison (1851-1938), who passed it on to Thomas Gwyn Elger (1838-97), who passed it on to Walter Goodacre (1856-1938), who passed it on to Hugh Percy Wilkins (1896-1960) before being acquired by Garfinkle. These individuals were highly accomplished and highly respected lunar observers in their day. This instrument would have been very similar to that employed by Denning in his surveys of the sky. The reader will note the mirror was re-silvered and tested at Kitt Peak, where its accuracy was estimated to be about 1/25 wave; not bad at all for an antique Newtonian and a testimony to the kind of quality available to those Newtonian users of old.

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Denning, as a world class authority on the planet Saturn, discusses many curious phenomena recorded by observers, both historical and contemporary. For example, on page 200 Denning states that only two relaible determinations of the planet’s rotation period had been made; the first by Sir William Herschel dating to 1793, who provided a value of 10 hours and 16 minutes, and another almost a century later by Professor Asaph Hall, who estimated Saturn’s day length to be 10 hours 14 minutes. Denning informs us that both observers had estimated these timings by following the progress of bright and dark spots in the upper atmosphere of the planet. Curiously, he also notes that Hershel made an earlier estimate of 10 hours 32 minutes and 15 seconds.

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 Author’s note: The modern accepted value for the length of a Saturnian day is 10 hours, 39 minutes and 22 seconds, which is especially close to Herschel’s measure. It never ceases to amaze this author how astonishingly close this celebrated astronomer from antiquity did using equipment most modern observers would turn their nose up at.

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On pages 201 through 205, Denning launches into a most fascinating discussion on Saturn’s rings, reminding of facts that are all too often forgotten, such as the greater brightness of the inner ring (with the Cassini division proving the cut off) in comparison with the outer. On page 201, he states that the angular width of the Cassini division is 0.4″ which translates to a real width of 1700 miles. He brings to our attention the remarkable fact that very small telescopes are able to see this division, such as a report by Charles Grover, who observed it clearly with a 2 inch refractor (see a note towards the bottom of page 209 for reference).

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Author’s note: The actual width of the Cassini division is depenedent upon where it is measured in respect of the planet. At its widest extent, it is about 0.75″ but is significantly narrower as it is measured along an imaginary line running through its central meridian. That said, Denning was clearly aware that on an extended object at least, angular resolution was considerably better than that attributed to double star measurement. The Dawes Limit for a 2 inch aperture, for example, being 4.57/2 = 2.29″.

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Two splendid drawings of Saturn accompany the text; one made by the distinguished Belgian observer F. Terby (page 203) and another on page 201, by Denning himself (with his 10 inch reflector, power 252 diameters). Both reveal great skill in their execution, showing not only the celebrated Cassini division but also the Crepe ring and the Encke division in the outer ring. Extensive banding on the globe is also recorded in both drawings.

On page 204, in a section entitled Discordant Observations, Denning brings our attention to the dangers of attributing too much to telescopes of very small aperture:

It is curious that the details of Saturn have occasioned more dissension amongst observers than those of any other planet. This may have partly arisen from the great distance of Saturn, the comparitive feebleness of his light, and complexity of his structure. The planet is usually better defined than either Mars or Jupiter; but with tolerably high powers on small instruments the image is faint, and features so diluted that the impressions received cannot always be depended on, especially when the air is unsteady. A fluttering condition of the object is sufficient in itself to cause deception.

pp 204.

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Author’s note: As Denning reminds us; small telescopes run out of light quickly and, as a result, many details that can readily be seen in larger aperture instruments will prove much more elusive in smaller telescopes.Beware of observers who produce seemingly wondrous details on planets in small aperture telescopes under unfavourable and/or low altitude conditions!

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Denning provides an excellent overview of the Saturn’s magnificent satellite system, at least, as was then known. Small telescopes can show several quite well; Titan, Tethys, Rhea, Iapetus and Dione, can be seen well in a 4 inch refractor. Enceladus, Denning informs us, can be seen with moderate aperture, but background stars are often  mistaken for it.  When the rings are presented edge on, good opportunities are afforded to observe satellite eclipses and can be observed with telescopes of modest aperture. On page 205, he reproduces a very nice sketch recorded by a one Mr. Capron who observed Titan in transit across the face of the planet on the evening of December 10, 1877, using a 8.25 inch reflector, power 144 diameters.

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A Curious Endnote: Mr. Denning did not discuss the physical nature of Saturn’s ring system. In particular, whether they were solid structures or made up of many smaller, composite particles. This interesting question was addressed by the great Scottish physicist, James Clerk Maxwell in a most brilliant essay published in 1859. In this paper, Maxwell showed conclusively that were Saturn’s rings solid, they would be rapidly torn apart by Saturn’s tidal forces.

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Chapter XIII: Uranus and Neptune

Covering pages 215 to 226.

By the time Denning penned his marvellous tome in amateur astronomy (1891), the discovery of Uranus was over a century in the past, but as one will see from the opening pages of this chapter, it stimulated a great deal of discussion among observers and whether or not it was misidentified by many astronomers before the time of Herschel. As you’d expect, Denning does a good job recounting the details of Herschel’s gradual realisation that he had discovered a whole new world beyond the orbit of Saturn, but also some curious details of how it was repeatedly missed by earlier observers:

Flamsteed observed it on six occasions beyween 1690 and 1715, while Le Monnier saw it on 12 nights in the years from 1750 to 1771, and it seems to have been pure carelessnesson the part of the latter which prevented him from anticipating Herschel in one of the gretest discoveries of modern times.

pp 216

Though it was doubtless seen visually throughout antiquity owing to its faint visibility ( magnitude 6) to the naked eye, details concerning its visual apperance had to await access to telescopes of significantly larger aperture. Coupled with a small mean angular size of 3.6″ and comparitive faintness, many seasoned observers of the 19th century found it difficult to see any surface markings on the planet, with many, including William Lassell, working with a 2 foot speculum in Malta (1862), reporting either a bland disk or, at best, faint banding.  Further observations conducted with some of the large refractors at Nice (30 inch), France (1889), and the 23 inch equatorial refractor (1883) at Princeton, USA, seemed to affirm the presence of equatorial banding on the planet but what is particularly revealing is the lack of any accurate determination of the planet’s rotation period, with estimates of anything between 10 and 14 hours. That such uncertainty persisted concerning the latter provides solid evidence that the markings on Uranus were of an extremley faint nature and required quite powerful telescopes and considerable patience to discern. Denning himself alludes to the difficulty of observing such banding:

With my 10 inch reflector I have suspected the existence of the belts, but under high powers the image is too feeble to exhibit delicate forms of this character.

pp 219.

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Author’s note: The modern accepted value for Uranus’ rotation period is 17 hours 14 minutes. This author has never observed banding with a fine 5 inch f/12 achromatic reffractor, and has (possibly) glimpsed one or two of them in a modern 8 inch Newtonian, though consensus opinion gravitates toward a 12 inch as about the minimum aperture needed to see these features with any certainty.

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It will be made clear to the reader that the knowledge that Uranus was strongly tilted on its axis was not at all apparent at the end of the 19th century when Denning penned his tome, though he does mention some wildly discordant results obtained by the French observers, M. Perotin, working with the great Nice refractor, and the brothers Henry at the Paris Observatory. The former noted only a small (10 degree) tilt of the planet relative to the common plain of the orbits of its satellites, whilst the latter found the value to be 41 degrees!

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Author’s note: These data only serve to compound the singular difficulty of observing Uranus, even with large, observatory class telescopes. No consensus could be made regarding its tilt (really 97 degrees) owing to the difficulty in observing this small and faint planet far from the warming rays of the Sun. Denning notes that the motions of the then four known satellites of Uranus showed that they orbited retrogradely (see page 221), but a little note of clarification is needed here: the planet itself, like Venus, orbits in a retrograde sense (as defined from the north pole of the Sun), but its satellites have orbits that are prograde with respect to Uranus itself. In the aftermath of some cataclysmic event in its early history, Uranus was set ”rolling its way,’ as it were, around the Sun; in sharp contradistinction to all the inner worlds of the solar system, which spin like tops as they move in their orbits.

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Mr. Denning dedicates the remainder of the chapter to Neptune, which, as one can imagine, is presented as even more mysterious than Uranus. After providing an excellent overview of the historical details of the discovery of the planet (involving Messrs Le Verrier, Adams and Galle), Denning does offer us a fascinating account of how the planet was seen hald a century before them (1795) by Lalande:

It was found that the planet was previously observed by Lalande on May 8 and 10 1795, but its true character escaped detection.This astronomer had observed a star of the same  star in the exact place noted on the former evening, he rejected the first observation as inaccurate and adopted the second, marking it doubtful. Had Lalande exercised discretion , and confided in his work, he would hardly have allowed the matter to rest here. A subsequent observation would have at once exhibited the cause of the discrepancy, and the mathematical triumph of Le Verrier and Adams, half a century later, would have been forstalled.

pp 223

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Author’s note: Hindsight is a wonderful thing, is it not!

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Denning informs us that the telescopic sight of Neptune is far from inspiring.

Our knowledge of this distant orb is extremely limited, owing to his apparently diminutive size and feebleness. No markings have ever been sighted on his miniature disk, and we can expect nothing until one of the large telescopes is employed in the work. No doubt this planet exhibits the same belted appearance as that of Uranus, and there is every probability that he possesses a numerous retinue of satellites. In dealing with an object like this small instruments are useless; they will display the disk, and enable us to identify the object and determine its position if necessary, but beyond this their powers are restricted by want of light.

pp 223

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Author’s note: Denning’s surmising concerning this distant planet has been proven to be well founded. Owing to its tiny size (2.7″ at opposition) it is never much to write home about and is indeed a rather lacklustre telescopic sight.  Yet it does exhibit belts (and spots)  like that of Uranus. Indeed planetary scientists group these worlds together as ‘icy giants’ of the solar system, and even show up in a number of extrasolar planetary systems thus far characterised by astronomers.

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On page 223, Denning does mention William Lassell’s idea that Neptune may have a very faint ring system but is sceptical as to its veracity in light of the limited observations made with large telescopes at the time of writing of his book. Lassell did however discover Neptune’s largest satellite, Triton, just 17 days after the planet itself was discovered. With a maximum elongation only 18″ from Neptune, this 14th magnitude would have been most difficult to pinpoint, and is thus a testimony of the skills employed by its discoverer.

On page 224, Denning presents a very curious paragraph exploring the possibility of trans Neptunian planets! He mentions, in particular, the theoretical work of a one Professor Forbes, who wrote a memoir in 1880 “tending to prove that two such planets exist.”

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Author’s note: There is nothing new under the Sun! Astronomers have long entertained the idea that more worlds lie beyond our ken than we can ‘see’ with the telescopes we devise. Such discoveries continue apace in the 21st century.

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Chapter XIV

Comets and Comet Seeking

Covering pages 227 through 259.

Supersitious ideas with regard to comets as the harbingers of disaster have long since been discarded  for more rational opinions. They are no longer looked upon with as ill omened presages of evil, or as:

“From Saturninus sent,

to fright the nations with a dire portent.”

Many refernces are to be found  among old writings to the supposed evil influence of those bodies, and the dread which their appearance formerely incited in the popular mind.Shakespeare makes an allusion to the common belief;

“Hung be the heveans with black, yield day to night!

Comets, importing chnace of time and states,

Brandish your crystal tresses in the sky;”

and in relation to the habit of connecting historical events with their apparition, he further says;

When beggars die, there are no comets seen;

The heavens themselves blaze forth the death of princes.”

But happily, the notions prevalent in former times have been superseded by the more enlightened views naturally resulting from the acquirement and diffusion of knowledge; so that comets , though still surrounded by a good deal of mystery, are now regarded with considerable interest, and welcomed, not only as objects devoid of malevolent character, but as furnishing many useful materials for study. Mere superstitions have been set aside as an impediment to real progress, and more intelligent age has recognized the necessity only with facts and explaining them according to the laws of nature; for it is on facts, and their just interpretation that all true searches after knowledge must lie. Comets are properely regarded as bodies which, though far from being thoroughly understood in all the details of their physical structure and bahaviour, have yet a wonderful history, and one which, cold it be clearly elucidated, would unfold some new and marvellous facts.

pp  227/8

William Denning was not only a world class planetary observer; he was also the discoverer of four comets viz, 1881V, 1890VI, 1892 II and 1894 I, and with the exception of the comet discoveries Holmes and E Hind, the only bodies of such kind unveiled since the time of Caroline Herschel (discussed in another chapter of the book). Denning indpendently found Comet 1891 I, less than 24 hours after it was first seen by the great American  astronomer, E.E. Barnard. To find a comet takes a great deal of committment, of course, invariably requiring many hundreds or thousands of hours of sweeping the skies at dusk and dawn in the hope that a new icy interloper would find its way into the field of view of his telescope. Indeed, Denning’s tally of comet discoveries was not rivalled until much later into the 20th century, when the most remarkable George Alcock, added to Britain’s prestige for finding these curious celestial interlopers.

In this chapter, we gain a unique glimpse of the state of scientific knowledge regarding comets in the late 19th century, as well as the methods which were employed in their detection. Almost immediately, we gain the unmistakable impression that Denning found observing comets to be a partcularly exciting passtime, and his enthusiasm proves infectious;

Whilst its grand appearance in the firmament arrests the notice of all classes alike, and is the subject of much curious speculation amongst the uninformed, its merits, apart from other considerations, the most assiduous observation on account of the singular features it displays and the striking variations  they undergo. Indeed, the visible deportment of a comet during its rapid career near perihelion is so extraordinary as to form a problem, the solution of which continues to defy the most ingenious theories. The remarkable changes in progress, the quickness and apparent irregularity of their development, are the immediate result of a combination of forces, the operations of which  can neither be defined or foreseen. Jets and flame and wreaths of vapour start from the brilliant nucleus; while streaming away from the latter, in a direction opposite to the Sun, is a fan shaped tail, often traceable over a large span of the heavens and commingling its extreme fainter limits with the star dust in the background.

pp 228

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Author’s note: Denning was all too aware of the unpredictability of comets, having observed them with great enthusiasm from his home in Bristol. Indeed, of all celestial objects viewed by amateurs it arguably the comet which has the greatest ability to inspire or disappoint, even in the 21st century. And despite great strides in understanding comet morphology, astronomers can hardly ever reliably predict what kind of spectacle they will put on as they near the warming rays of the Sun. It was perhaps this unpredictability that so attracted Denning to these marvellous objects.

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Because of their rather elusive nature, at least at the end of the 19th century, discovering a comet was a sure way to come to the notoriety of one’s astronomical peers. Cash prizes and (more commonly) medals were issued by the astronomical societies of the world for the man who would find a new comet. Indeed, a caricature of Mr. Denning was published in the April 9 1892 issue of Punch Magazine in honour of the discovery of his third comet (1892 II), which he stumbled across on the evening of Friday, March 18 1892. His discovery was also featured in The Times.

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William F. Denning of Comet fame; a cartoon published in Punch Magazine Vol 102 April 9 1892. Image credit: Wiki Commons.

Denning informs us (bottom of page 228) that some 300 comets had their orbits worked out at the time (1891), and a further 500 had been observed and deduces from this that they must be extremely plentiful. He then provides a general description of how a typical comet evolves as it moves closer to the Sun;

Usually the telescope gives us the earliest intimation that one of these bodies is approaching us.It is first seen as a small round nebulosity, with probably  a central condensation  or stellar nucleus of the 10th or 11th magnitude. The whole object expands as its distance grows less, and it assumes an elongated form preparatory to the formation of a tail. The latter varies greatly in different instances; it may either be a narrow ray, as shown in the soutern comet of January 1887, or  fan shaped extension like that of the great comet of 1774. Barnard’s Comet of December 1886 exhibited a duple tail. Occasionally a fine comet bursts upon us suddenly, like that of of 1843 or 1861.The former was sufficiently bright to be discovered  when only 4 degrees from the Sun, and the latter presented itself quite unexpectedly as a magnificent object in the strong twilight of a June sky.

pp 229.

Although all the scientific facts were not in Denning’s possession, he does mention something of the physical nature of comets:

Comets are not compact or coherent  masses of matter; they more likely represent vast groups of planetary atoms, more or less loosely dispersed and sometimes forming streams. The effect of sunlight upon such assemblages  will be that the whole mass becomes illuminated  according to density, and that no phase will be apparent insomuch as the light is able to penetrate through its entirety.

pp 230

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Author’s note: Denning’s assertion that comets are loose assemblages of matter proved to be correct! Cometary bodies are well described as ‘dirty snow balls’ with average densities about 50 per cent that of water, and which typically contain water ice, dust, and an enrichment of simple organic molecules including hydrogen cyanide, methanol and formaldehyde.

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On page 230 Denning provides us with details of how a  comet’s orbit may be computed. If three trustworthy observations of the comet’s position have been made, it is possible to distinquish between the conic sections represented by the parabola, ellipse and hyperbola. Only comets that follow elliptical orbits, he informs us, are periodic.

Thereafter Mr. Denning launches into a fascinating general discussion on a great many comets dating back to the 16th century. On page 231 he mentions that it is his belief that Sir William Herschel may have mistakenly identified some comets as nebulae, as they were subsequetly shown not to exist in the locations he noted for them. The chapter is generously illustrated with drawings of famous comets, many of which were seen and drawn by Denning himself.

Comet seeking has more to do with the quality of the observer than the equipment he/ she employs. Afterall, as he reminds us, “Messier discovered all his comets using a small 2 foot telescope of 2 1/2 inches aperture magnifying 5 times and a field of 4 degrees.” On page 252 he gives more specific recommendations on the kind of instrument suited to comet sweeping:

Opinions are divided as to the most suitable aperture and power for this work. Any telescope from 4 to 10 inches may be employed in it. A low power (30 to 50) and a large  field(50 to 90′)  eyepiece are imperative; and the instrument, to be really effective, should be mounted to facilitate sweeping either in a vertical or horizontal direction. A reflector on an altazimuth stand is a most convenient form for vertical sweeps. The defining capacity of the telescope need not necessarily be perfect to be thoroughly serviceable, the purpose being to distinguish faint nebulous bodies, and not details of form. Far more will depend upon the observer’s aptitude and persistency than upon his instrumental means, which ought to be regarded as a mere adjunct to his powers and not a controlling influence in success, for the latter lies in himself. Very large instruments are not often used, because of their necessarily restricted fields. Moreover, small instruments, apart from its advantage in this respect, is worked with greater flexibility and expedition.

pp 252/3

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Author’s note: Comet seeking by amateurs has greatly declined in recent years owing to the establishment of automated surveys using large, observatory class telescopes, but it is still true that the majority of successful comet hunters in the last few decades employ moderate (generally less than 16 inches) aperture telescopes, capable of fairly wide fields of view, and low powers. A good example is the telescopes used and owned by the Canadian amateur astronomer and discoverer of 22 comets, David H. Levy.

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On page 252 through 253, Denning provides the reader with most invaluable data concerning the number of hours he and his astronomical contemporaries worked while comet hunting. He mentions this rather in passing, as the subsection really concerns the suitability of the English climate to the task of seeking comets:

From some statistics printed in the ‘Science Observer,’ Boston, it appears that during the seven months from May to November, 1882, Lewis Swift was comet seeking during 300 hours. I have no English results of the same kind, but my meteoric observations will supply a means of comparison. From June to November, 1887 (six months), I was observing during 217 hours, and for nearly a similar period during the last half of 1877, though in each year work work was only attempted with the Moon absent. My results for 1887 averages 36 hours per month, which is little less than the average derived from the comet seeking records above quoted. It is therefore fair to suppose that as much may be done here as in some regions of the United States.. Mr. W. R. Brooks wrote me in 1889, saying, ” We have much cloudy weather in this part of America. While in other portions of the country clear weather abounds, it is not so in this section, where much of my work has been done. This is a most fertile section; the beautiful lake region of N.Y.; but it is for this reason a cloudy belt. It is far different in Colorado and California. In the latter place, at Lick Observatory, I hear they have 300 clear nights a year; a paradise for the astronomical observer.

pp 251/2

Yet, then as now, the keen telescopist may have to contend with prolonged periods of cloudy weather. In a letter he received from Professor Swift dated July 30, 1889 he says:

“I arrived home, after a few weeks’ visit to the Lick Observatory, on March 1, and have not had half a dozen first class nights since; not in thirty years have I seen such prolonged rainy and cloudy weather.”

pp 252.

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Author’s note: This provides solid evidence of the both the industry of these Victorian observers and the likely frequency of opportunities available to observe. Factoring in the many other nights when Denning was actively observing while the Moon was in the sky, it is not unreasonable to think that the British climate is much more amenable to pursuing our wonderful hobby than is commonly believed.

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On page 255, Denning presents more historical data showing the average annual rate of discovery of cometary bodies from 1782 through to 1889. Prior to 1845, between 1 and 2 comets were discovered per year, but after 1845 it increased several fold, so that by the 1880s it had increased to about 5 per year. This undoubtedly reflects the increasing number of astronomers joining the race to uncover them. In addition, he presents data illustrating at what times of the year these comets were discovered. During the months of July and August, the number of comets discovered peaked but was generally higher in the second half of the year. Denning does not provide an explanation but it seems reasonably clear that the longer periods of twilight during the summer months afford greater opportunities for observers to pick up comets approaching the Sun. In addition, the second half of the year is warmer in the northern hemisphere (where virtually all comets desribed by Denning were discovered) making comet sweeps more pleasurable.

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Author’s note: What invaluable information we have here!

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Chapter XV

Meteors and Meteoric Observations

Covering Pages 260 to 285

No one can contemplate the firmament for long on a clear moonless night without noticing one or more of those luminous objects called shooting stars. They are particularly numerous in the autumnal months, and will sometimes attract special attention either by their frequency of apparition or by their excessive brilliancy in individual cases. For many ages little was known of these bodies, though some of the ancient philosophers appear to have formed correct ideas as to their astronomical nature. Humboldt says Diogenes of Apollonia who probably belonged to the period intermediate between Anaxagoras and Democritus, expressed the opinion that, “together with the visible stars, there are invisible ones which are therefore without names. These sometimes fall upon the Earth and are extinguished, as took place with the star of stone which fell at Aegos Potamoi.” Plutarch, in the “Life of Lysander,” remarks: “Falling stars  are not emanations or rejected portions thrown off from the ethereal fire, which when they come into our atmosphere are extinguished after being kindled; they are, rather, celestial bodies which, having once had an impetus of revolution, fall or are cast down to the Earth, and are precipipitated , not only on inhabited countries, but also, and in greater numbers, beyond these into the great sea, so that they remain concealed.”

In later times however, opinions became less rational. Falling stars were considered to be of a purely terrestrial nature, and originated by exhalations in the upper regions of the air……..Another theory, attributed to Laplace, Arago, and others, was that meteors were ejections from lunar volcanoes. But these explanations were not altogether satisfactory in their application. The truth is, that men had commenced to theorize before they had begun to observe and accumulate facts. They had learned little or nothing as to the numbers, directions, and appearances of meteors, and therefore, possessed no materials on which to found any plausible hypothesis to account for them.

pp 260/1

Denning was the ultimate outdoor man, preferring if at all possible, to be under a starry sky than being huddled up indoors. He was the ultimate observer, being equally adept both with and without a telescope. Indeed, as I have alluded to earlier, he probably spent more observing time with his naked eye than peering through the eyepiece of his permanently stationed reflecting telescope. Denning was an international authority on meteors. Indeed, it was his research in this area of observational astronomey that led to his election as fellow of the Royal Astronomical Society. That said, it was the reaction to his ideas (and exacerbated by a midlife illness) concerning these luminous bodies that ultimately led to his withdrawal from public service.

Once again, Mr. Denning opens this chapter with exquisite prose, extolling the knowledge of the ancients who pondered the nature of the ‘shooting stars’ just as solemnly as we do today. Indeed, he reminds us that many ideas that we receive as ‘modern’ or ‘contemporary’ often had their originations in the ruminations of minds that have long since departed this world. What is more, the march of time is no guarantee that ideas become any more developed than they were when they were first conceived of in the backwater of human history. All of human thought is to be likened to the winding course of a meandering river and, more often than not, intellectual brilliance is no safeguard against being dead wrong.

While many observers throughout history were keen to report the brightness and colour of meteors, few had the presence of mind to record the direction and longevity of such events. It is these latter facts, Denning explains, that were of greater importance in elucidating their true nature. He continues to ascribe credit where it was due to a number of  pioneers in this field including Edward Heis (1806–77), who conducted a systematic study of meteors including their trajectories on the celestial sphere. He also acknowledges the work of the German astronomer, Julius Schmidt (1825–1884), based at Bonn and Athens, and contributions from his compatriots, Professor Alexander Herschel (1836–1907), grandson of Sir William Herschel, and Mr. R. P. Greg, who collated and analysed large bodies of observational data to calculate the all important radiant points; loci on the celestial sphere through which meteors were seen to emanate from.

By the 1850s it was becoming clear that meteor showers were strongly associated with comets, but it was the Italian astronomer, G.V. Schiaparelli, who in 1866 definitively associated them with the orbits of comets. Analysing the Perseid meteor shower, Schiaparelli provided incontrovertible evidence that they were associated with the orbit of Comet III 1862. He also showed that the meteor showers of November were also strongly correlated with the orbit of Comet Temple 1861 (page 264). Meteor showers, it became clear, occur when the Earth swept up debris from the tails of comets as it intersected their orbits in space.

Thereafter, Denning engages in a brief but fascinating discussion of meteorites that had fallen to earth without being completely destroyed. On page 266, he lists a number of historical meteorite finds dating back to 1478 BC through to the end of the 19th century. On page 267, he notes that these meteorites fall into a variety of categories: those in which iron was found to constitute their bulk (siderites), those of mixed stone and metallic composition; siderolites; and those entirely composed of rocky material; aerolites.

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Author’s note: While the nomenclature of meteorites has changed in modern times, the basic classification system employed by Denning still stands today. The vast majority are classified as chondrites, and are composed of a variety of silicate minerals and small amounts of organic matter, arranged in roughly spherical particles called chondrules. About 8 per cent are achrondrites, characterised by their more amorphous nature and resemblance to terrestrial igneous rock. The remainder have substantial metal content (stony irons or iron meteorites).

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Through pages 267 through 270, Mr. Denning relates some fascinating firsthand accounts of fireballs, unusually bright, violent, and long lived meteors, including a few of his own description, that occurred throughout the 19th century. Some of these were real monsters. For example, in the table presented on page 268 of his book, he relates that one fireball witnessed by a one G.von Niessl, began to incandesce about 250 miles above the ground and fell to an altitude of 85 miles before disappearing. In so doing, it crossed a whopping 1200 miles of sky!

Denning includes an eyewitness testimony of a meteorite which fell in Mazapil, Mexico, on the evening of November 27 1885 (see page 270).  And in another account, he relates the sonic boom associated with a fireball which streaked across the sky on the evening of November 23 1877 in which “the explosion of a 13 inch bombshell, consisting of 200 lb.of iron, would not have produced a sound of one hundredth part the intensity of the meteor explosion.”   It is clear from these communications that Denning had a very special interest in the human dimension of meteor science; when earth and sky converge to break the monotony of an otherwise ordinary day.

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Author’s note: While I have enjoyed some memorable fireballs over the years, some notable apparitions were entirely missed owing to the ‘call of nature,’ for want of a better expression. Perhaps the most memorable missed opportunity occurred in the early evening of Monday, February 29  2016, when an unusually loud and bright green fireball streaked across the skies of Scotland and northern England, creating quite a media sensation. A telescope had already been set up in my back garden for the purposes of conducting some routine double star observations, when I retired indoors to ‘spend a penny.’ A few minutes later, I heard my mobile phone ping as a few excited friends texted me asking if I had seen the fireball streaking across the sky. “No,” I replied, “I was on the thrown!”

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On page 271 through 272, Mr. Denning describes some extraordinary meteor storms that occurred in history, most notably on November 12 1799, and one in the wee small hours of November 13 1833, when the people of North America counted more than 1000 meteors per minute over the space of two hours! Another storm apparently occurred on November 27, 1872, “when 33,000 meteors were counted by Denza and his assistants at Moncalieri, Italy between the hours of 5h 50m and 10h 30m P.M.

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Author’s note:Such reports have become the stuff of legend in modern times, with all meteor showers in recent years being more of a disappointment than anything else. It’s almost as if some events in the heavens are winding down?! Or maybe we just need a peppering of new comets!

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On page 272 through 273, Denning launches into a fascinating discussion on the subject of telescopic meteors (see the curious drawing by W.R Brooks, reproduced in figure 57.), that is, meteors seen moving across the field of view of the telescopic field:

Observers engaged in seeking for comets or studying variable stars employ low powers and large fields, and during the progress of their work notice a considerable number of small meteors. At some periods these bodies are more plentiful than at others, and appear in such rapid succession that the observer’s attention is distracted from the special work he is pursuing to watch them more narrowly and record their numbers. They range between the 7th and 11th mags. Winnecke in the year 1884 noticed 105 of these objects on thrity two evenings of observation with a 3 inch finder, power 15, and field of 3 degrees. I have also remarked many of these objects when using the comet eyepieces of my 10 inch reflector and find they are apparently more numerous than the ordinary naked eye meteors in the proportion 22 to 1. It would be supposed from the great rapidity with which the latter shoot across the firmament that the smaller telescopic meteors are scarcely distinguishable by their motion, as they dart through the field instantaneously and only be percepitible as lines of light. But this impression is altogether inconsistent with the appearances observed. They possess no such velocity, but usually move with extreme slowness, and not unfrequently the whole of the path is comprised within the same field of view. The eye is enabled to follow them as they leisurely traverse their courses, and to note peciliarities of aspect. Of course, there are considerable differences of speed observed, but as a rule the rate is decidely slow and far less than that shown by naked eye meteors. I believe that telescopic meteors are situated at great heights in the atmosphere, and that their diminutive size and slowness of movement are due to their remoteness.

pp 272/3

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Author’s note: Granted, any reasonbaly experienced observer has seen meteors streak across the field of view of his/her telescope, but who among you would take the time to measure the ratio of naked eye meteors in comparison to those seen at the telescope? Personally, I have never taken the time to even consider such a question, though I concede that the description of the various speeds of telescopic meteors is accurate from my own experiences in the field. Denning offers us a good explanation as to why some appear to move relatively slowly across the field of view; they are located at great altitudes. What remarkable insight! What a wonderful passtime this could become for someone with modest equipment! See here for more ideas on this.

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On pages 274 through 276, Denning provides brief overviews of all the major meteor showers enjoyed in the northern hemisphere throughout the year.  On page 277 we gain a glimpse of the sheer enthusiasm he had for observing such phenomena. Figure 58. shows a curious drawing of the changing apperance of a slow moving meteor as it made its way across the sky during the early evening of December 28 1888. He noted its change in brightness at various intervals as well as its morphology and committed the apparition to memory!

The remaining pages of the chapter describe the details of finding meteor radiants and the question of whether these points are stationary or whether they in fact move. We now understand that meteor radiant points are not stationary but are seen to slowly drift eastward by about a degree per day on average. Denning disputed this apparently and the interested reader may learn more about this interesting subject by examining other bodies of literature. See here for one example.

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Chapter XVI: The Stars

Covering Pages 286 through 323.

The planetary observer has to accept such opportunities as are given him; he must use his telescope at the particular seasons when his objects are well presented. These are limited in number, and months may pass without one of them coming under favourable review. In stellar work no such irregularities can affect the progress of observations. The student of sidereal astronomy has a vast field to explore, and a diversity of objects of infinite extent. They are so various in their lustre, in their grouping, and in their colours, that the observer’s interest is actively retained in his work, and we often find him pursuing it with unflagging diligence through many years. No doubt there would be many others employing their energies in this field of labour but for the uninteresting character of star disks, which are mere points of light, and therefore incapable of displaying any detail. Those who study the Sun, Moon or planets have a large amount of surface configuration  to examine and delineate, and this is ever undergoing real or apparent changes. But this is wholly wanting in the telescopic images of stars, which exhibit a sameness and lack of detail that is not satisfying to the tastes of every observer. True there are some beautiful contrasts of colour and many striking differences in magnitude in double stars; there are also the varying position and distance of binary systems, the curious and mysterious fluctuations in variable stars, and some other peculiarities of stellar phenomena which must, and ever will, attract all the attention that such important and pleasing features deserve. And these, it must be conceded, form adequate compensation for any other shortcomings. The observer who is led to study the stars by comparisons of colour and magnitude or measures of position, will not only find ample materials for a lifelong research, but will meet with many objects affording him special entertainment. And his work, if rightly directed and accurately performed, will certainly add something to our knowledge of a branch in which he will certainly find such delectation.

pp 286/7

As I explained previously, W.F. Denning was arguably the last master of observational astronomy. Many of his contemporaries were already specialists, knowing much about one area of astronomy but having relatively little practical knowledge of other areas. Not only were his contributions to astronomical knowledge confined to the shallows of the solar system, they extended far beyond the empire of the Sun, to include the distant stars and nebulae. Indeed, during his routine comet sweeps he was one of the first to observe Nova Aquilae on June 8, 1918, and just over two years later he discovered Nova Cygni 1920. Further afield, his keen eye uncovered two score new nebulae never before seen. Indeed, if there were anyone who could convey the joyous enthusiasm of observing the stellar heaven, it would be Mr. Denning. It is in this outward bound spirit of exploration that we shall continue to study the knowledge of this extraordinary human being.

In the opening pages of this chapter, Denning sets out the basic route by which the keen amateur might secure knowledge of the starry heaven. Familiarity with the Greek alphabet is, of course, essential to understanding how the stars within the various constellations are presented. In general, the brightest luminary is designated alpha, the second most, beta, and so on. Denning suggests that the basic outlines of the classical constellations be memorised (page 290). While he acknowledges that the star patterms often do not resemble the classical figures very strongly they are useful because they conveniently divide up the celestial sphere, “giving each a distinguishing appellation, so that it might be conveniently referred to.

Interestingly, Denning warns against trying to change this traditional system of parsing the visible night sky:

There are some who object to the method of the Chaldean shepherds because the seies of grotesque figures on our star maps and globes bear no natural analogies. But it would be unwise to attempt an innovation in what has been handed down from the myths of a remote antiquity for;

“Time doth consecrate,

And what is grey with age, becomes religion.”

pp 290.

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Author’s note: How prescient of Denning to raise this issue. This author vividly remembers a telescope forum thread entitled “Unlearning the Constellations,” raising this very issue. What arrogance to think that any such move would yield anything worthwhile! How disrespectful it is to dishonour the traditions of every generation since the dawn of civilization! On whose authority did you write? Your own? Needless to say, the same proposal, like all other historical attempts, fell flat on its face.

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Mr. Denning continues this chapter by discussing the (then) popular activity of double star observing and mensuration, emphasising the use of the filar micrometer as a tool that could be exquisitely mated to the telescope. He then discusses the kinds of instruments that are suitable to such an activity, rightly acknowledging the traditiional role of the classical refractor as highly favoured but also admitting that the reflecting telescope is almost as good:

....it is notable that refracting telescopes have accomplished nearly the whole of the work. But reflectors are little less capable, though their powers seem to have been rarely employed in this field. Mr. Tarrant has lately secured a large number of accurate measures with a 10 inch reflector by Calver, and if care is taken to secure correct adjustment of the mirrors, there is no reason why this form of instrument should not be nearly as effective as its rival. Mr. Tarrant advises those who use reflectors in observing double stars, ” to test the centering of the flat at intervals during the observations, as the slightest shift of the large mirror in its cell will frequently occasion a spurious image which, if it by chance happens to fall where the companion is expected to be seen, will often lead to the conclusion that it has been observed. In addition any wings or the slightest flare around a bright star will generally completely obliterate every trace of the companion, especially if close and of small magnitude, and such defects  will in nine cases out of ten, be found to be be due to defective adjustment. Undoubtedly, for very close unequl pairs the refractor possesses great advantages over a reflector of equal aperture; in the case of close double stars the compenents of which are nearly equal there appears to be little, if any, difference between the two classes of instruments; while for any detail connected with the colour of stars the reflector comes to the fore from its being perfectly achromatic.” These remarks from a practical man will go far to negative the disparaging statements sometiimes made with regard to reflectors and stellar work, and ought to encourage other amateurs possessing these instruments to take up this branch in a systematic way.

pp 290/2

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Author’s note: Having extensively tested classical and contemporary apochromatic refractors, catadioptric and Newtonian telescopes on a suite of double stars, this author reached the following conclusions, which are in complete agreement with the findings of Mr. Denning and Mr. Tarrant:

Apochromatic refractors are no better than a good traditional achromat of decent relative aperture in splitting doubles. This is amply borne out in historical studies; see here and here for examples.

Catadioptrics make excellent, high resolution double star telescopes.

Millimetre for millimetre, refractors are better than Newtonians at resolving the tightest, unequal pairs, but the differences are largely eliminated by employing a Newtonian of slightly larger aperture, provided the prevailing seeing conditions allow.

In general, the optical quality of a telescope is far less important than the prevailing sky conditions, as well as the skills the would be observer brings to the table. This author’s 8 inch f/6 reflector was found to be noticeably superior to a first rate 5″ f/12 at divining close doubles of either unequal or equal magnitudes, the generous gain in aperture completely negating any advantages incurred by using a smaller, unobstructed aperture.

These results fly in the face of self promoted ‘authorities’ who have zealously defended the refractor as the only choice for such work. To continue to do so is downright dishonest and actually completely misleading to those who wish to explore this branch of visual astronomy. See here, here and here for more discussions on this topic. The reader will also be interested in these results obtained using a reflecting telescope with sub f/5 relative aperture.

Denning’s remarks concerning the superior colour fidelity of reflecting telescopes (in this case, the silver on glass variety) are also wholly valid. Despite the wonderful pantheon of adjectives coined to describe the colour of stars in refractors, none enjoy the perfect achromaticity of the reflector.

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Concerning the theoretical separation of members of a binary star system, Denning appeals to the work of the Reverend William Rutter Dawes, who offered his famous formula for splitting doubles of equal brilliance (actually magnitude 6), which asserts that the tightest double star that can be resolved is approximated by 4.56″/ D where D is the aperture in inches. He provides a convenient table of theoretical separations on page 292 for the interested reader.  On page 293, Denning offers the additional findings of the optician, a one Mr. Dallmeyer, who provided this result which agrees well with Dawes’ findings:

“In all calculations I have made, I find that 4.33 divided by the aperture gives the separating power.”

pp 293.

Denning, being intimately familiar with the behaviour of large and small apertures offers this cautionary note:

A large aperture will sometimes fail to reveal a difficult and close comes to a bright star when a smaller aperture will succeed. This is due to the position of the bright diffraction ring, which in a large instrument may overlap the faint companion and obscure it, while in a small one, the ring lies outside and the small star is visible.

pp 293.

While many amateurs continue to erroneously conflate the ability of a telescope to split a given pair with its optical quality, Denning prefers to lean on the wisdom of his learned predecessor:

Dawes concluded that; “tests of separation of double stars are not tests of excellence of figure.”

pp 293.

In a curious footnote provided  at the bottom of page 293, we learn more of measurements made at the telescope regarding the position of the first diffraction ring;

Mr. George Knott, of Cuckfield, mentions that the radius of the first bright diffraction ring of a stellar image, for a 7.3 inch aperture is 1.01″, and for one of 2 inches 3.7″.  Mr. Dawes is quoted as giving 1.25″ for a 7 inch, 1.61″ for a 5.5 inch and 3.57″ for a 2.4 inch. These figures exceed the theoretical values, if the latter are adopted  from Sir G.B. Airy’s “Undulatory Theory of Optics”, where for mean rays we have;

Radius of object glass in inches x radius of bright ring in seconds = 3.7.

pp 293.

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Author’s note: In independent work, this author derived the formula 185/D  where D is expressed in millimetres represented the locus of the first diffraction ring. Converting to millimetres and plugging the numbers above into this equation gives the radius of the first diffraction ring for a 7.3 inch and 2 inch aperture respectively as;

185/185 = 1″ and  185/50 = 3.7″

These figures, which are derived from Airy’s theoretical work, show that they are in perfect (perhaps too perfect?) agreement with Knott’s measurement.

Dawes’ results for the 7, 5.5 and 2.4 inch apertures are, respectively;

185/178 = 1.04″, 185/139.7 = 1.32″, and 185/60= 3.08″ which are indeed lower than those predicted in theory.

The latter values are still quite close to those derived in Airy’s theory, and like any measured value, they may be subject to some systematic error. Given the wiggle room for error, I wonder whether Dawes’ findings are more reliable than those produced by Knott? Alas, we shall never know for sure, but it remains a fascinating topic of discussion nonetheless.

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The next section of the chapter diverges considerably from the previous in discussing the number of stars of varying glory in the firmament. When I was a boy, I learned from various books that about 3,000 are visible to the naked eye from a clear, dark sky, though Denning offers a figure of approximately 5,000 (page 293). Of course, the number will vary according to the kind of sky one encounters as well the keeness of one’s visual system. Denning’s own estimate may also reflect the darker skies he enjoyed, writing as he did in the late Victorian era.

With every increase in magnitude, there is a great increase in number, but there is no fixed power law that might enable us to compute how many more stars there might be as the magnitude is increased. Argelander estimates that each magnitude exhibits a rise of about 300 per cent. Indeed, in data presented on page 294, he provides these figures, collated from a survey between 2 degrees south of the equator all the way to the north pole:

1st: 20

2nd: 65

3rd: 190

4th: 425

5th: 1100

6th: 3200

7th: 13,000

As one can see, the 3 fold increase per magnitude increase is only very approximate, but nonetheless it is a useful result.

Of course, without the unblinking eye of a photometer, a legitimate question arises; how does one estimate stellar magnitudes accurately? Denning discusses this on page 294 through 295, where he presents magnitude estimates made by Sir John Herschel and Struve (he doesn’t mention which one). Interestingly, for the stars between magnitude 4 and 6, the discrepancy amounts to about 0.5 stellar magnitudes, but as the stars become fainter (down to magnitude 14 or so), the discepancies become larger. This is entirely understandable, as fainter stars will be more difficult to estimate.

Intriguingly, Denning was also cognizant of two newly minted photometric surveys conducted at Harvard College and Oxford University Observatories, which showed much better agreement with each other, with 31 per cent of the stars monitored differing by 0.1 magnitude, 71 per cent differing only by 0.25 stellar magnitudes and 95 per cent of all stars surveyed showing no greater than 0.33 stellar magnitude difference. Reading from the summary of that comparitive survey, he notes, “a great step has been accomplished towards an accurate knowledge of the relative lustre of the stars.” pp 295.

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Author’s note: Mr. Denning lived during the rise of astrophysical science, where the eye was rapidly being replaced by instruments that were considerably more sensitive than the human eye. It is unclear as to how he felt about this new era dawning on the world, but he gives me no reason to suppose that he did not embrace it. Afterall, Denning was ostensibly a truth seeker in everything he did.

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On page 295 through 297, Denning describes the visual appearance of the Milky Way, both to the naked eye but also through the telescope. He describes the profusion of stars which vary both in number, grouping, brilliance and variation of hue as the telescope is moved from one field to another. But some regions of the Milky Way are conspicuous by their absence of stars and accordingly he mentions the Coalsack and various dark, cavernous regions running through Scorpius and Sagittarius which offer ” striking contrast to the silvery sheen of surrounding stars.” pp 296. Such regions were marvelled at, and studied to great effect, by his distinguished American contemporary, E.E. Barnard.

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Author’s note: Sweeping the Milky Way on a dark, moonless night with a large telescope remains a great joy for this author. With a modern, low power, wide angle ocular, a field in excess of 2 degrees is possible. I imagine Denning using his favourite comet seeking eyepiece, delivering a power of about 32 diameters in a field fully 1.25 degrees wide (see page 254 for details of his equipment) for the express purpose of exploring the vast reaches of the Milky Way. The activity never ceases to amaze, especially when one contemplates the reality of what the eye presents; our God is an awesome Creator, with an eye for beauty that far exceeds that which can even be dimly grasped by the mind of man. As the ancient psalmist declared:

For the director of music: a psalm of David

The heavens declare the glory of God;

the skies proclaim the work of his hands.

Psalm 19:1

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The effects of stellar scintillation are described on pages 297 through 298. He informs us that it was Sir Robert Hooke, who in 1667 provided the explanation for this charming natural phenomenon, which he attributed to “irregular refractions of the light of the stars by differently heated layers in the atmosphere.” Denning also clearly understood why planets, in comparison to stars, do not exhibit much in the way of scintillation;

The planets,” he writes, “are little subject to scintillation as they present disks of sensible size, and thus are enabled to neautralize the efect of atmospheric interferences.”

pp 297

Curiously, he points out that while higher altitude sites, where many observatories were being established, present thinner air which generally increases the steadiness of the images garnered at the telescope, there were, even then, exceptions to this rule:

In February 1888, Dr. Pertner, of the Vienna Academy of Sciences, found “that scintillation of Sirius was actually greater at the top of Sonnblick, 10,000 feet high, than it was by the base of the mountain, and he formed the opinion that scintillation has its origin in the upper strata of the atmosphere and not in the lower as usually assumed.” It would appear from this that lofty situations do not possess all the advantages claimed for them in regard to the employment of large telescopes.

pp 298

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Author’s note: I have first hand experience of this. At a site located 8,500 feet up in the White Mountains of Eastern California, the seeing was often (but not always) more turbulent than it was in my own back yard at sea level!

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A mere ten years before Denning was born, astronomers of the ilk of Bessel, Struve and Henderson had painstakingly obtained the first stellar parallaxes that enabled them to measure the vast distances to the nearby stars. On page 299, he reports on the progress that had been made in his own lifetime, including (revised) estimates for 61 Cygni, but also for alpha Centauri, alpha Crucis and Vega (alpha Lyrae). The parallaxes obtained (just fractions of a second of arc), established their distances with fairly good accuracy. Vega, for example is quoted as having an annual parallax of 0.15″ corresponding to a distance of 22 light years. The modern value places this system a little farther away, at 25 light years. Regardless of the errors still at large in these early data, Denning was fully cognizant of the mind boggling separations between the stars!

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Author’s note: Though we have known the colossal distances between the stars for the best part of two centuries, it never ceases to impress this author how much these facts have a bearing on what one sees and contemplates at the eyepiece. Facts have consequences. Seeing is a time machine; the telescope a wondrous tool that empoyers humanity with the ability to actively see the past, both recent and remote.

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On page 300, Mr. Denning resumes his discussion of individual double and multiple stars. Ever mindful of the experience level of his readership, he provides excellent visual descriptions of the most comely stellar systems that require only modest telescopic aid to fully enjoy. These include, Polaris, Rigel, Antares, Sirius (which he fully admits is exceedingly difficult from anywhere in England owing to its very low altitude). Figure 62. presents what are presumably his own artistic renderings of a suite of favourites including, gamma Leonis, Arietis, Andromedae and Virginis, delta Cygni and Serpentis. All of these systems would have been easy targets for his 10 inch With Browning reflector and indeed can be just as easily savoured by an observer equipped with a small refractor of say three or four inch aperture.

On pages 302 through 305, Denning presents a comprehensive table of double stars of increasing difficulty, starting with sub arc second pairs and extending through to systems that are within easy reach of ordinary binoculars. In this table, their measures are presented together with some notes supplied by the astronomer who conducted these measures. These include contributions from Burnham, Tarrant, Schiaparelli, Leavenworth, Engelmann, Perottin, Struve II and Maw.

The reader will be made aware of several sub arc second measures made by Tarrant, who, as we have previously learned, employed a 10 inch Calver reflector. Tarrant’s tightest system is lambda Cassiopieae (dated 1887.3), the components of which are both magnitude 6.5 and separated by a mere 0.45 seconds of arc!

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Author’s note:  How wonderful and important historical books can be in establishing universal truths in visual astronomy! This author has split several sub arc second pairs with his 8 inch f/6 Newtonian reflector from his backyard.

Iustitia, iustitia, iustitia!

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In a curious note at the bottom of page 301 and carried over to page 306, Denning mentions something of interest:

Certain doubles such as theta Aurigae, delta Cygni and Zeta Herculis are more easily seen in twilight than on a dark sky; and some experienced observers, conscious of this advantage, have observed excellent measures in daylight. Mr. Gedhill says: “such stars as gamma Leonis and gamma Virginis, are best measured before or soon after sunset.”

pp 301/306

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Author’s note: Living in a country where strong twilight exists from May through to late July, and with little else in the sky at the time, I have become especially accustomed to viewing double stars in incomplete darkness and can fully vouch for Denning’s assertion as well as Gedhill’s endorsement. Many an evening have I passed examining the beautiful, calm images of eta 1 and 2 Lyrae, iota Cassopieae, epsilon, kappa, pi and xi Bootis, as well as Alula Borealis & Australis, using small instruments from the comfort of my back garden. Sunset and twilight conditions are indeed excellent times to catch these stellar systems. Indeed, more than half the fun is finding them in a less than dark sky.

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More so than in other chapters, Denning darts about a bit in this, the penultimate chapter of the book, discussing variable stars before returning once again to multiple star systems. Arguably the most interesting is the theta Orionis system; affectionately known as the Trapezium owing to its strong resemblance to this geometric form. The quartet are, of course, visible in all but the smallest instruments but is the reader aware of when the other, fainter components of this fascinating cluster of neonatal stars were first observed? Denning provides us with the answer, and then some;

In 1826 Struve discovered a fifth star, and in 1830 Sir John Herschel found a sixth; these were both situated a little outside the trapezium. All these stars have been seen in a 3 inch telescope. The great 36 inch equatorial at Mount Hamilton has added several others; one was detected by Alvan G. Clark ( the maker of the object glass) and another by Barnard. These were excessively minute and placed within the trapezium. Barnard has glimpsed an extremely minute double star exterior to the trapezium and forming a traingle with the stars A and C……….The fifth and sixth stars have been supposed to be variable, and not without reason; possibly the others are equally likely to change, but this is only conjecture. Sir John Herschel says that to perceive the fifth and sixth stars ” is one of the severest tests that can be applied to a telescope:” yet Burnham saw them both readily in a 6 inch a few minutes before sunrise on Mount Hamilton in September 1879.

pp 319/20

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Author’s note: The 5th and 6th stars of the Trapezium can often prove elusive but are more a test of local seeing conditions than raw visual acuity. I have seen them many times in my career, but perhaps the most memorable was through a beautiful 4 inch f/15 classical achromat in ambient air temperatures of minus 11 Celsius; conditions that I have seldom enjoyed since. That night the air was rock stable, as if I were viewing the cosmos through a finely polished precious stone. Denning mentions the complementary visions of two legendary observers; E. E. Barnard, who had incredibly sensitive eyes capable of picking up objects on the precipice of what is humanly possible, and the eagle eyes of S. W. Burnham, who brought the international double star community to its knees in discovering hundreds of new doubles with a fine 6 inch f/15 Clark refractor where others, using instruments of far grander estate, reported nothing out of the ordinary.

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The variable star and nova enthusiast will find much that is of interest, both scientifically and historically, on pages 309 through 316, with a neat table of the main variable stars being presented on page 311.

On page 315 to 316, Mr. Denning brings up a perennial favourite amongst arm chair astronomers; the curious case of Sirius’ allegedly red colour in antiquity:

Cicero, Seneca, ptolemy and others speak of Sirius as a red star, whereas now it is an intense white; and if we rely on ancient descriptions similar chnages appear to have affected other prominent stars. But the old records cannot be implicitly trusted, owing to errors or transcibers and translators; and Mr. Lynn (‘Observatory’ vol ix p. 104) quotes facts tending to disprove that Sirius was formerly a red star.

pp 315/6.

 

At the bottom of page 316, Denning embarks on a discussion of groupings of stars, what we today call star clusters. He states that the average eye can make out 6 members of the Pleaides and a seventh, though more elusive, “is occasionally remarked.”  Denning claims that in 1877 he “distinctly made out 14 stars in this group.” That’s quite a feat of visual acuity and perhaps an indicator of darker, clearer skies in the late Victorian period than of late. His telescope revealed Tempel’s nebula enveloping Merope, a not so trivial visual target in the early 21st century, even with a moderately sized instrument.

Denning also provides some brief notes on some of the more celebrated star groupings including Praesepe in Cancer, a delightful sight in small telescope, Coma Berenices and a most wonderful description of Chi Persei, known to us today as the Double Cluster (Caldwell 14):

Perceptible to the eye as a patch of hazy material lying between the constellations of Cassiopeia and Persei. In the telescope it calls a double cluster, and is one of the richest and beautiful objects that the sky affords. The tyro who first beholds it is astonished at the marvellous profusion of stars. It can be fairly well seen in a good field glass, but its chief beauties only come out in a telescope, and the larger the aperture the more striking they will appear. It is on groups of this character that the advantage of large instruments is fully realized. The power should be very low, so that the whole of the two clusters may be seen in the field. An eyepiece of 40, field 65′, on my 10 inch reflector, presents this object in its most imposing form.

pp 317/8

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Author’s note: From August right through to early Spring, one of the objects this author visits routinely, even religiously,  on every clear evening when the Moon is out of the sky is the Double Cluster. I simply never tire of beholding the majesty of this stately grouping of stars; corruscating jewels of diamond, sapphire, topaz and ruby, assault the eye, and induces feelings of pure, unadulterated joy. Small wonder it is the stuff of poetry!

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Chapter XVII Nebulae and Star Clusters

Covering Pages 324 to 346

These objects, though classed together in catalogues, offer some great distinctions which the observer will not be long in recognizing. It was thought at one period that all nebulae were resolvable into stars, and that their nebulous aspect was merely due to the confused light of remote star clusters. But modern telescopes, backed up by the unequivocal testimony of the spectroscope, has shown that nebulous matter really exists in space.The largest instruments cannot resolve it into stars, and it yields a gaseous spectrum.The conjecture has been thrown out that it may be considered as the unformed material of which suns and planets are made.

pp 324

William Denning penned his great treatise on visual astronomy at the crossroads between new and old worlds. Advances in astronomy were revealing a cosmos far grander and more complex than anyone had dared to imagine just a few decades before. Spectroscopy, photography and the rise of giant telescopes provided new ways of reading the book of nature. Yet all the while, Denning kept on doing what he did best; quietly going about his solitary vigils of the heavens, his simple telescope ever ready to carry him to distant worlds. In this, the final chapter of the book, he presents a distillation of what was known about the most distant objects in the heavens, the mysterious nebulae, star clusters and Island Universes and how the ordinary man could engage in a systematic study of these magnificent objects.

Denning opens this interesting chapter by setting forth a summary of the progress made in discovering and classifying the various nebulae; gaseous, elliptical and spiral, as well the various open and globular star clusters characterised at the time of writing. Such was the rate of discovery of new nebulae that D’Arrest considered the real possibility that their number would turn out to be “infinite.” A new edition of Sir John Herschel’s catalogue of deep sky objects had been published by the Royal Astronomical Society in 1888, listing some 7840 items and which collated the works of the great pioneers in this arena of observational astronomy, including the Herschels, Lord Rosse, D’Arrest, Marth, Tempel, Stephan and Swift. The success of these astronomers, Denning points out, was largely due to the employment of larger aperture telescopes that could collect more light to bring fainter and fainter objects into view. What’s more, only with large telescopes could any real structure be delineated within many of these objects. Concerning celebrated targets such as the Whirlpool Galaxy, the Dumbbell, Horsehoe and Crab Nebula, for example, he states:

An instrument of smaller diameter is quite inadequate to deal with them. They can be seen, it is true, and the general shape recognized in the most conspicuous examples, but their details of structure are reserved for the greater capacity of larger apertures.

pp 325

Ever fond of quoting statistics, Mr. Denning informs us that the distribution of nebulae is far from uniform, being highly concentrated toward the constellations of Leo, Coma Berenices and Virgo, but much more sparsely toward Perseus, Taurus and Auriga, for example. Curiously, because of a lack of knowledge concerning the nature and distance of many of the nebulae, some astronomers formed the opinion that they underwent changes in form and even position! Denning himself is inclined to agree in principle:

It is in the highest degree probable that changes occur in the visible appearance of certain nebulae, though the opinion is not perhaps supported by a suffiecient number of instances.

pp 327

Indeed, he presents a series of curious historical accounts of alleged “variable nebulae” phenomena in pages 327 through 330, which the reader may find interesting.

When it comes to nebulae, there appears to be a great range of acuities among astronomers as to what is and is not actually seen. Consider the intriguing story of the Merope Nebula recounted by Denning on page 329 and 330:

On Oct. 19, 1859, Tempel discovered a faint, large nebula attached to the star Merope, one of the Pleaides, and at first mistook it for a diffused comet….An impression soon gained ground that this object was variable; for while Schmidt, Chacornac, Peters, and others saw it with small instruments, it could not be discerned by D’Arrest and Schjellerup with the large refractor at Copenhagen. Swift saw the nebula easily in 1874 with a 4.5 inch refractor, and has observed it with the aperture contracted to 2 inches. Backhouse reobserved it in 1882 with a 4.5 inch refractor. Yet in March 1881 Hough and Burnham sent a paper to the Royal Astronomical Society with an endeavour to prove that the nebula did not exist! They had frequently searched for it during the preceeding winter, but not a vestige of the object could be seen in the 18.5 inch refractor at Chicago, and they regarded the supposed nebula as due to the glow proceeding from Merope and neighbouring stars. But photography has entirely refuted this negative evidence, and has shown, not only Tempel’s nebula, but others involving the stars Maia, Alcyone, and Electra, belonging to this cluster.

pp 329/30

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Author’s note: What a remarkable story! The reader will recall how Mr. Burnham (mentioned previously), arguably the most keen eyed double star observer in history, couldn’t see the Merope Nebula even with such a large telescope! It would indeed appear to be the case that the ability to perceive faint objects is not at all related to the eye’s ability to resolve details. Some folk will be better deep sky observers than others! Perhaps the episode might have been entirely avoided had E.E. Barnard been assigned to the project instead of Burnham!

Different strokes for different folks!

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Pages 334 through 340 contain interesting summaries of the most celebrated deep sky objects visited by amateurs in any age, including the Great Nebula in Orion, the Andromeda Galaxy (nebula in Denning’s day), the Dumbbell, Ring and Crab Nebula. Spiral nebulae such M51 and M91 and what Denning refers to as “elliptical nebulae” including M81 & M82. He also discusses the prominent globular clusters, such as M13 in Hercules, as well as M2, M3, M5, M15 and M80. Denning also mentions the magnificent Omega Centauri, the delight of antipodean skies, which Sir Hohn Herschel referred to as, “beyond all comparison the richest and largest object of the kind in the heavens”. In the final pages of the book, Denning presents a much more extensive list of deep sky objects, together with some brief descriptive notes. He also includes 10 nebulae on page 342, all discovered as a result of his own comet sweeps near the north pole, between 1889 and 1890.

Denning provides us with some details of the techniques he used while sweeping the sky for nebulae. Again he stresses the considerable advantages of decent aperture:

Those who sweep for nebulae must have the means of determining positions, and a small telescope will be inadequate to the work involved. A reflector of at least 10 inches, or a refractor of 8 inches, will be require; and  a still larger instrument is desirable, for to cope successfully with objects of this faint character needs considerable grasp of light. The power employed should be moderate; it must be high enough to reveal a very small nebula, but not so high as to obliterate a large, diffused, and faint nebula………With a low power a very extensive field will be obtained , and a large part of the sky may soon be examined, but it will be done ineffectively. It is better to use  a moderately high power, and thoroughly sweeping a small region. The work is somewhat different to comet sweeping; it must proceed more slowly and requires greater caution, for every field has to be attentitively and steadily scanned. If the telescope is kept in motion, a faint nebula will pass unseen. Some of these objects are so feeble that they are only to be glimpsed by averted vision. When the eye is directed, say to the E. side, a faint momentary glow comes from the west side of the field; but the observer discerns nothing on looking directly on the object.

pp 339/40.

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Author’s note: The reader will note that Denning clearly understood the concept of using averted vision to detect objects on the precipice of invisibility, the oldest unambiguous reference this author has thus far come across, and clear evidence that he was indeed a highly skilled and accomplished deep sky observer. In addition, Denning places a 10 inch reflector (presumably of the silver on glass variety) on par with a 8 inch refractor for deep sky work.

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Denning ends this chapter with an encouraging note to other amateurs:

The discovery of new nebulae offers an inviting field to amateurs. Vast numbers of these objects have escaped previous observation, for though the sky has been swept again and again, its stores have not been nearly exhausted…..The region immediately outlying known objects may also be regarded as prolific ground for new discoveries.

pp 341

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Afterword: The Significance of Denning’s Literary Work for the Contemporary Amateur.

Not for Public Viewing.

If you’ve enjoyed this commentary and wish to read more about these and other historical issues, please consider my up and coming book: Tales from the Golden Age of Astronomy.

Sincerely,

Neil English

De Fideli.

Tales from the Golden Age: The German Selenographers.

Lunar Day by Henry White Warren’s Recreations in Astronomy (1879). Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Do the words of a poem lose their poignancy once its author departs this world?

Can the limp of ‘progress’ outshine the ‘grand procession’ of great accomplishment?

Can a culture, basking in the glory of its own achievement, be made mute by a faithless generation of technocrats?

Can an optical bench test inspire more than a night spent behind the eyepiece of a grand old telescope?

Let us venerate that which is deserving of veneration!

Whose crown shall we adorn with a laurel wreath?

Let us sing again of old dead men.

And clear the cobwebs from their medals.

For they have no equal in the present age;

No muse to light their way.

 

After the publication of Hevelius’ universally celebrated Selenographia in 1647, as well as J.D Cassini’s improvements of 1670, progress with mapping the lunar surface telescopically was painfully slow, entering as it did, a very ‘long night.’ But by the end of the 18th century and throughout much of the 19th century, several German astronomers, amateur and professional alike, using modest telescopes by today’s standards, heralded a golden era of lunar cartography that ushered in the Space Age.

Tune in soon to read the whole story…………………

De Fideli.

The Pioneers of Parsonstown.

Birr Castle, Co. Offaly, Ireland, as it appears today.

Birr Castle, Co. Offaly, Ireland, as it appears today.

Dedicated to the memory of Peter Grego (1966-2016).

The picturesque, rural town of Birr in the County of Offaly, lies at the geographic centre of the Irish Republic. Inhabited in some capacity since the Bronze Age, a monastic settlement was established there by St. Brendan the Elder, which probably dates to the 7th century AD, and in the centuries that followed, Birr became the ancestral home of the O’ Carroll clan, the ruling Gaelic family of the northern territory of the ancient kingdom of Éile. In the aftermath of the Norman invasion of the 12th century, a castle was built there and continued to be administered by the O’Carroll’s, who were required to pay tribute to the Butlers of Ormonde, overlords of the district, whose capital was established in the neighbouring county of Kilkenny. In the aftermath of the English Plantation of Ireland in the 17th century, Birr Castle became the seat of the Parsons dynasty, the Earls of Rosse, beginning in 1620, when the civic areas were annexed to it, subsequently becoming known as Parsonstown.

From the 17th century onwards the Gaelic Irish were reduced to the status of tenants and landless peasants on their ancestral lands. Members of the O’Carroll clan were however, granted new lands in the colonies of Maryland and one family descendant, James Carroll of Carrolltown, went on to become the sole Catholic signatory of the American Declaration of Independence.

Evidence of British colonial rule can still to be seen in the elegant Georgian architecture of the modern town, with its tree-lined malls, and well-planned avenues, which still have the power to delight the eye. A railway, printing works and distillery provided employment to local families and a workhouse offered some relief to the starving peasants, a million of whom lost their lives during the famine years. A garrison of English soldiers was also established in the town. But like all Irish municipalities once administered by the iron fist of British Imperialism, the political winds of change swept rapidly through the region, as agrarian agitation by the Fenians, Land League and the Irish Parliamentary Party led to the dissolution of the landlord system, which also included the estate of the Earls of Rosse. As a symbolic act of the new order, the Gaelic Athletic Association also held the first All-Ireland Hurling Final at Birr in 1888. Remarkably, though its population was decimated in the mid-19th century owing to the ravages of the Irish potato famine (1845-52), the modern town of Birr, the inhabitants of which number about 6,000, has scarcely grown in size from its pre-famine population, making it one of the most pristine Irish heritage towns in existence.

After Birr Castle became Crown property in 1620, the Parsons family held several key offices in the administration of Ireland. William Parsons became Commissioner of Plantations and Surveyor-General of Ireland. His brother, Sir Laurence Parsons, became Attorney-General for the province of Munster and in the years that followed, the Castle was considerably enlarged and a successful glass works established which further aided the local community with employment opportunities. In the aftermath of William Parsons’ death in 1628, Birr became the epicentre of conflict between Catholics and Protestants. In 1641, a rebellion by Irish Catholics broke out. In January 1642, the castle itself was besieged by the Molloys, Coghlands and Ormonders , the factions engaging in brutal combat for five days. In some desperation, the noble incumbent, William Parsons, son of Sir Laurence, fled to the English army stationed at Dublin, and never returned. He died in 1653.

The troubles escalated during the time William’s son, Laurence, took up residence at Birr Castle after he father’s passing. This time, England was faced with the prospect of crowning a Catholic King, the Duke of York, who became James II in 1685. Laurence Parsons and his family departed for London leaving an unscrupulous heathen in charge of running the family estate at Birr, a one Colonel Heward Oxburgh, who, in 1689, seized complete control of the castle and its garrison, using it as a base for the forces loyal to William of Orange. Sir Laurence together with two of his confidants, were placed on trial by Oxburgh, accused of being traitors to King James II, the last Catholic King to rule the British Isles,  but were later granted a reprieve and rescued by William’s men.

More turmoil followed, when in 1690, the Castle was once again besieged by an army led by the Duke of Berwick, an illegitimate son of James II, who himself was not long deposed in the Glorious Revolution of 1688. During the exchange of fire, cannon balls flew through the parlour window, leaving marks in the walls of the north flanker which can still be seen to this day. Lady Parsons was even forced to relinquish the lead cistern she used for salting beef so that it could be melted down for bullets. Eventually though, the besieging army was finally repulsed, and the Parsons family returned to relative peace thereafter. The bloody events of the 17th century marked a watershed in the history of the castle, as well as the family who made it their home. A new dynasty of Parsons were to emerge from the ashes.

Throughout the 18th century, Birr castle became a popular haunt for some of the must cultivated individuals in Europe. Sir William Parsons, the 2nd baronet(in the new regime), was a close friend of the gifted composer, Georg Frideric Handel, who gave him an engraved walking stick in appreciation of the patronage which led to his magnum opus – Messiah – being first performed in Dublin. His grandson, another Sir William, the 4th baronet, began an ambitious project of landscaping the grounds of Birr Castle. Transforming bog land into an ornate lake, he planted beech trees and demolished the last of the ancient towers of the original fortress so as to complete the sweeping view of the demesne.

Sir William also devoted much of his time to the Volunteer movement, which sprang up towards the end of the eighteenth century, ostensibly to defend Ireland from the threat of French invasion, but effectively to force the English government to give concessions to the Irish Parliament. His son, Sir Lawrence, 5th baronet, became well-known as a patriot statesman, whose friend and colleague, the Irish revolutionary, Theobald Wolfe Tone(1763-98), referred to him as ‘one of the very very few honest men in the Irish House of Commons’. This personal integrity led him not only to oppose the Union with all his strength, but also to expose the bribery the British used to push it through. Evidently disgusted with the passing of the Act of Union in 1800, Sir Laurence retired from politics at the beginning of the 19th century, though he later accepted the post of Joint Postmaster General and attended the laying of the foundation stones of Dublin’s magnificent General Post Office build during his term of office. He devoted the autumn years of his life to literature.

The ornate Georgian facade of Dublin's General Post Office, famous for the staging of the 1916 Easter Rising which led to Irish independence from Britain. Image credit: Kaihsu Tai.

The ornate Georgian facade of Dublin’s General Post Office, famous for the staging of the 1916 Easter Rising, which led to Irish independence from Britain. Image credit: Kaihsu Tai.

Sir Laurence, the second Earl of Rosse, had three sons, the eldest of whom, William (also known as Lord Oxmantown), succeeded his father as third baronet upon his death in 1841. Unlike his father before him, the third Earl had a penchant for all things scientific, especially astronomy, and we learn of his first forays in the art of telescope making as early as 1827. The illustrious career of Sir William Herschel (1738-1822) proved to be a huge influence on the young William Parsons (1800-67), inspiring him to read mathematics at Trinity College, Dublin, where he graduated with a first class honours degree in 1822. And although he resolved to embark on a scientific career, his baronial status required that he take part in public life. To that end, he entered Parliament for King’s County (later renamed Offaly) in 1823, where he enjoyed a reasonably successful career, which he brought to an end in 1834. Two years later he married Mary Wilmer-Field, who hailed from Heaton, Yorkshire. The marriage was a long and happy one, and together they had four sons, all of whom displayed considerable intellect in adult life. Lady Mary was also a gracious host for all the scientists who were to work at Birr, and took an active interest in the work of her husband. The couple took up residence at Birr castle after William’s parents retired to Brighton, England, in search of milder climes. As master of his own baronial home, William was free to pursue his scientific career.

William Parsons ( Lord Oxmantown), Third Earl of Rosse ( 1800-67).

William Parsons ( Lord Oxmantown), Third Earl of Rosse ( 1800-67). Image credit: Wiki Commons.

William Parsons lived in a singularly interesting time for telescopic astronomy. Refracting telescopes were justifiably popular, especially after the innovations heralded by the genius of Joseph von Fraunhofer(1787-1826) in Germany, who had brought high quality achromatic refractors to market astride state-of-the-art clock-driven mounts that gracefully tracked celestial objects as they moved across the sky. But Parsons was a scientist, and he was compelled to pursue reflectors rather than refractors owing to the very limited aperture of the latter. He wanted to see the nebulae of Messier and Herschel better than anyone before him. Perhaps he had seen too many of his astronomical acquaintances follow the fashions of the time; which almost invariably involved double star mensuration with small aperture refractors. Indeed, according to the late Sir Patrick Moore, he completely abandoned the refractor early in his astronomical career. Parsons had clearly decided to go after bigger fish, and was convinced that mirrors were the way to go. And to that end, he set about grinding his own.

Like many astronomers of his day, Lord Oxmantown had to learn the noble art of casting and grinding mirrors to the required geometrical shape from scratch. He was vociferous about making the details of the construction of fine optical wares public knowledge, condemning the often secretive culture of telescope makers who came before him. As was the custom in those days before silver-on-glass reflectors, he had to use speculum metal mirrors consisting of an alloy of copper and tin as the reflective surface (discussed in much greater detail in this author’s up-and-coming book). To this end, he employed his considerable inventiveness to construct a steam-powered grinding machine with a power output of 2 horse power (~1.5KW). The mirror blank, placed in a vat of water to prevent its over-heating and expansion, was rotated slowly by the contrivance whilst the polishing ‘tool’ was made to move to and fro across the metal surface by a couple of cranks placed at right angles to each other. By considerable trial and error, Oxmantown was able to construct a series of increasingly large specula, first a 15-inch and then a larger 24-inch, both of which proved to be of very high quality.

Unlike Herschel before him, who had dispensed with the use of a secondary flat mirror in order to conserve the amount of light reaching his eye, and which gave rise to the tilted mirror of the Herschelian design, Lord Oxmantown returned to the closed-tube Newtonian configuration, finding out by experiment, that it reduced turbulence on account of the observer being located at a large enough distance from the mouth of the open tube. He also showed that tilting the mirror in the Herschelian fashion introduced unwanted aberrations to the images that were much less manifest in the Newtonian design. His mounting strategy, however, was quintessentially Herschelian in form, with all its attendant weaknesses.

After many false starts and setbacks, he managed to cast and figure a fine 36-inch speculum with a focal length of 27 feet (f/9 relative aperture) in 1839. The mirror was an alloy of 126.4 parts copper with 58.9 parts tin which produced a fine, white metal. The optical flat mirror was tested by comparing a distant object in daylight, first with a fine achromatic telescope and then using the same telescope that had formed an image after its reflection in the mirror. Any distortions would have been readily seen and adjustments accordingly made.  After mounting the optics, Oxmantown’s friend, the distinguished mathematician (a pioneer in vector algebra), William Rowan Hamilton(1805-1865), whom he became acquainted with during his time at Trinity College, was the first to turn it on celestial targets, and later pronounced it as excellent. Lord Oxmantown also invited the distinguished astronomers, Sir James South (of double star fame) and Thomas Romney Robinson, to his estate at Birr Castle in order that they might test the telescope and pronounce assessments of its quality. Having just spent a considerable amount of time performing similar tests on the 13.3-inch (with an objective by Cauchoix) refractor at Markree Castle, Co. Sligo, first dedicated in 1834, the gentlemen astronomers stayed at Birr between October 29 and November 8 1840. The guest astronomers were duly impressed with Lord Oxmantown’s newly erected 36-inch, pronouncing it “the most powerful telescope that has ever been constructed,” and declaring it superior even to the late Sir William Herschel’s 48-inch behemoth. On all objects studies, which included, the Moon, double stars, open stellar clusters and nebulae, the 36-inch showed its optical excellence. Indeed, according to Robinson (who became the first Director of Armagh Observatory in 1823):

“It [was] scarcely possible to preserve the necessary sobriety of language, of speaking of the Moon’s appearance with this instrument, which discovers a multitude of new objects at every point of its surface.”

The venerable 36-inch reflector designed and built by Lord Rosse on a quintessentially Herschelian type alt-azimuth mounting.

The venerable 36-inch reflector designed and built by Lord Rosse on a quintessentially Herschelian type alt-azimuth mounting.

Robinson observed lunar features at a power of 900 diameters with the 36-inch reflector that were scarcely seen again for another 60 years, including the appearance of “two black parallel stripes in the bottom of Aristarchus,” which are now known to be depressions, and a series of “extremely minute craters” on the ridges of the crater Ptolemaeus.

Robinson also observed M31 in Andromeda and the Great Nebula in Orion (M42) in the hope that the great telescope at Birr might resolve them into stars. Examination of the Dumbbell Nebula (M 27) in Vulpecula and the Ring Nebula (M57) in Lyra showed that they remained wholly nebulous in the 36-inch.  Alas, while he detected the tell-tale signs of individual stars on the edges of M31, the results were at best ambiguous and only served to strengthen his conviction that these objects were fundamentally non-stellar in origin. Star clusters such as M13 and M92 in Hercules were reportedly breathtaking at high powers though the same instrument.

Lord Oxmantown was satisfied that he had indeed created a first-rate telescope that would contribute to scientific knowledge, and in the spirit of the age, warmly welcomed the finest observers across Europe to use the telescope for their researches:

Although the instrument and the laboratory where it was constructed are in the centre of Ireland,” he wrote, “the facilities of communication are such that those who desire further information can easily obtain it on the spot, and from their own estimate of the performance of the instrument”.

His invitation was enthusiastically accepted, and in due course, distinguished scientists and observers of the ilk of Sir John Herschel, George Johnstone Stoney, William Lassell, Otto Struve, George Bidell Airy, Franz Friedrich Brünnow and George Gabriel Stokes, all enjoyed time at the great telescopes designed by Lord Rosse.

Yet, as soon as the 36-inch was completed, Oxmantown had made plans for an even greater instrument that would remove the still pervasive ambiguity concerning the nature of the celestial nebulae:

“I think that a speculum of 6 feet aperture could be made to bear a magnifying power more than sufficient to render the whole pencil of light, and that in favourable states of the atmosphere it would act efficiently, without having recourse to the expedient, which Newton pointed out at the last resort, that of observing from the vantage of a high mountain…… an instrument even of the gigantic dimensions I have proposed might, I think, be commenced and completed within one year.”

In making the 72-inch reflector a reality, Oxmantown was faced with a daunting task. A mirror twice as large would have four times the area of the smaller 36-inch and would be much more difficult to successfully cast, grind and polish. Its much greater weight would make it considerably more challenging to mount stably as well. As Robinson later pointed out in a paper presented in 1845; it was not possible to melt down the appropriate quantities of copper and tin in the crucible used to create the 36-inch speculum. Indeed, three such crucibles would be called for, each 24 feet in diameter and weighing half a ton apiece. Oxmantown had to construct a giant chimney-shaped furnace to accommodate the three crucibles. To achieve the necessary temperatures to create the liquid alloy, 2000 cubic feet of turf cut from a local peat bog had to be combusted for ten hours before the melt was ready. It must have been quite an apparition to catch sight of the thick yellow smoke billowing upwards from the giant furnace, its eerie yellow and orange glow being clearly visible for miles around. The cylindrical metal blank, weighing in at a whopping 4 tons, was successfully cast, but an accident of some unknown nature occurred one month into figuring the giant metal slab with the result that a large crack rendered it useless. Undeterred, a plan was made to recast the same metal, and this time it was accomplished, though it was slightly thinner than the original, weighing a half ton less. The subsequent grinding and polishing phases also went well, and by April 13 1842, the mirror was completed.

Lord Rosse had to tread very carefully in considering the mounting for this giant telescope. The tube would be 58 feet long and as a result, it would not be possible to mount it in the way the 36-inch telescope was. If a Herschelian type mount were to be employed, the slightest breeze would set the giant telescope- which would  weigh over 150 tons when completed – swinging wildly from side to side, not only making observations impossible, but putting the lives of the observers and workmen operating the instrument in jeopardy. After much deliberation and consultation, Oxmantown settled on a mounting system set between two massive walls. These would be 70 feet long and 50 feet high, running parallel with the north-south line, so that celestial objects could only be examined as they crossed the local meridian. Indeed, for an object located on the celestial equator, the total viewing time would be restricted to an hour at most. But at least the great telescope would be able to view its target when it was highest in the sky and so less affected by atmospheric turbulence.

Construction started on the Parsons demesne at the end of 1842 and continued right the way through 1843 and 1844. A cast iron joint – similar to a modern universal joint – occupied the base of the mount, and upon it was bolted an 8 foot wooden box that would carry the giant mirror. Around this was placed the telescope tubing, fashioned from inch-thick staves, and held in position by a series of iron clamp rings. The tube tapered down to 7 feet at its extremities, making it a rather odd, cigar shape. Movement in declination was undertaken via a series of thick metal cables fastened to the top of the telescope, and maneuvered by a system of elaborate pulleys. Right ascension (to and fro) motion was accomplished with a manually-operated steering wheel. In addition to these course movements in both right ascension and declination, provision was made to allow fine adjustments in both axes to centre the object under study. Oxmantown also had the presence of mind to install finely meshed screens under the telescope, so as to protect workers from the accidental fall of eyepieces and other items of equipment. The financial outlay of the Leviathan was very considerable: £12,000 in the currency of the day!

The 72-inch aperture 'Leviathan of Parsonstown' c. 1860. Image credit: Wiki Commons

The 72-inch aperture ‘Leviathan of Parsonstown’ c. 1860. Image credit: Wiki Commons

Observing with the great telescope was never a solitary affair. Indeed, its operation always required a well-trained team of operators, who had to follow verbal instructions from the astronomer assigned to it on any night. Nor was the telescope ever fitted with a finder telescope! Instead, Oxmantown employed a low power, wide field ocular of his own design, with a magnification of 216 and possessing a generous true field of 31 arc minutes (so just large enough to show the full Moon) to centre objects to be studied. And while he had intended to install a clock drive to move the instrument in right ascension, in the end, this never came to fruition, neither under the Third Earl’s watch or that of his son, the Fourth Earl. After undertaking a series of mechanical trials over the winter of 1844, the instrument was deemed ready for operation in February 1845, when both Robinson and South were once again invited to Birr Castle to provide an assessment of its efficacy.

Alas, the weather didn’t cooperate and opportunities to test the Leviathan were few and far between. First light came for an hour or so on the evening of February 15, when the telescope was turned on Castor, a famous double star in the constellation of Gemini. To the delight of all in attendance, the system was easily and cleanly split, the components appearing more brilliant than any other telescope in existence. Next, the great light bucket was directed at M67, a small open cluster situated across the border into Cancer. Robinson and South reported that the faint stars in the cluster were magnificently rendered. Then the clouds rolled in again. And with further inclemencies in the weather occurring over the next  couple of weeks, it was decided to remove the primary mirror for further polishing – no mean task in itself as it required the combined effort of 25 or 30 workmen!

The working telescopes at Birr:, based on a portrait by Henrietta Crompton. Image credit: Wiki Commons.

While it is unquestionably the case that the 72 inch Leviathan of Parsonstown was very unwieldy by modern standards, Sir James South reported that he could uncap the telescope, have its position adjusted by the assistants on both axes and have a star centred for observing in about eight minutes! Second light occurred on March 4, where a spell of settled weather made observations possible up until March 13. No opportunities were missed to turn the great telescope on a suite of double stars, open clusters and nebulae that hugged the meridian at that time. It was over this period that Robinson and South declared the instrument optically excellent and capable of doing first class astronomical research. Shortly thereafter, the telescope was officially inaugurated by Dean Peacock, head of the (Protestant) Church of Ireland, who is said to have walked through the giant tube, inspecting it from one end to the other whilst donning a top hat with a raised umbrella above his head. In the milder months that followed, the Leviathan was turned on the nebula listed as number 51 in Messier’s famous catalogue (see the author’s previous chapter on Charles Messier), located in the Canes Venatici, was examined and its spiral structure clearly seen; a momentous discovery for sure, but one that was overshadowed by more terrible events.

A sketch of the Whirlpool Galaxy ( M51), as drawn by Lord Rosse in 1845 using the 72-inch Leviathan. Imahe credit: Wiki Commons.

A sketch of the Whirlpool Galaxy ( M51), as drawn by Lord Rosse in 1845 using the 72-inch Leviathan. Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

 

 

The summer of 1845 marked an atrocious turning point in the history of this small nation. By now, the potato famine was palpably showing its devastating effects (with 50 per cent of the crop having being infected with blight), and the peasants who worked the land throughout the county were beginning to starve. Lord Rosse was by now a peer in the British House of Lords, and still served as Lord Lieutenant and Colonel of Militia of Kings County. Admirably though, he put the needs of his countrymen first and after consulting with the British Prime Minister, Sir Robert Peel, and his panel of appointed scientific experts, provisions were made to import cheaply purchased maize and cornmeal from the New World, which helped somewhat but could not fully ameliorate the human disaster.

It was not until January of 1848 that Lord Rosse would resume active research with the great telescope. But when it was uncapped after a three year hiatus, the mirrors were found to have tarnished owing to the excessively damp weather that characterised the worst of the famine years. And though a second mirror had by then been successfully cast, it had not been polished to the required degree. But by February 16 both specula were ready for action and by month’s end, astronomical observations were in full swing once again. Indeed the great telescope remained in active service for many years thereafter. The magnificent instrument became the centrepiece of international attention, and tourists flocked to see it from all around the world. And it was all the more remarkable that its creator did it all off his own back, with no financial assistance from governments or monarchs, quite unlike the situation with Sir William Herschel (discussed in another chapter of the book).

According to research conducted by the late Sir Patrick Moore, the defining power of the Leviathan was called into question by a number of individuals, mostly casual observers, but affirmed by those who had been given the opportunity to observe with it on a regular basis. One such tyro is reported to have remarked:

They showed me something which they said was Saturn, and I believed them….

But the reader should note that such a monstrous telescope, with such a large aperture as it possessed, was much more sensitive to atmospheric turbulence than instruments of much smaller aperture, particularly the equatorially mounted classical refractors, which by now were adorning the observatories across Europe and North America.

Consider, if you will, the remarks of the distinguised Irish physicist and astronomer, George Johnstone Stoney (1826–1911), himself a native of the town of Birr, whose reputation as an observer was unquestioned and who carried out careful tests on the 72 inch instrument over an extended period of time (four years to be precise, over the period 1848-52):

The test usually applied was the performance of the mirror on the star of the 8th or 9th magnitude, magnification 750. Such stars are bright in the great telescope. They are usually seen as balls of light, like small peas, violently boiling in consequence of the atmospheric disturbance. If the night is good there will be moments now and then when the atmospheric disturbance will abruptly seem to cease for a fraction of a second, and the star is seen for an instance as the telescope really presents it. It is by the opportunities of such moments  that the performance of the telescope must be judged. With the best of your father’s* mirrors that I saw, the appearance at such opportunities was that of the light shining through a minute needle hole in a card placed in front of a flame. I think any practical astronomer will agree with me in the opinion that mirrors of 6 feet in diameter that bore the test bordered very closely indeed on theoretical perfection.

* Stoney is referring here to the third Earl of Rosse, but the communication was to his son, who succeeded to the title of fourth Earl by the time the scientific correspondence was published on April 2 1878.

As King Solomon of old knew, there is really nothing new under the Sun. Then, as now, casual observations are not likely to reveal any great truth but rather have the greater potential to disseminate untruth.

Indeed Moore, in his book, The Astronomy of Birr Castle, provides still more evidence that the mirrors made by the third Earl of Rosse were of high quality. In February of 1848, shortly after the Leviathan was dedicated, Romney Robinson described a fine night in which Jupiter presented with a ” remarkable appearance… full of faint striae running nearly parallel to them, and seemingly belonging to the brighter zones on each side.” And in 1889, a series of published drawings of Jupiter made by a later assistant of Lord Rosse, Dr. Otto Boeddicker between 1881 and 1886, show that they compared well with modern instruments of the same size, according to the noted planetary observer, Stanley Williams, who conducted such a study in 1935.

Still more evidence of its optical quality can be gleaned from a discussion of the telescope in Henry C. King’s classic tome, The History of the Telescope, where he notes that the Leviathan was capable of resolving very tight double stars. On one occasion, Robinson, South and Lord Oxmantown managed a clean split of gamma 2 Andromedae with a power of 828 diameters and a then separation of 0.5″.

Such testimonies show that while the telescopes of Lord Rosse were not ‘planetary’ instruments in the traditional sense (for they were seldom employed in this arena), they were more than capable of doing first rate science.

The enormous light gathering power of the Leviathan added to the tally of spiral nebulae. Indeed, by the end of 1850, a total of 14 such structures were positively identified by Lord Rosse and his astronomical assistants. These included M33, M31, M77, M95 and M99. It was even possible for Lord Rosse to begin to subclassify these spiral nebulae into a variety of classes, including barred, diffuse and irregulars. He also suspected that many of the elliptical and lenticular nebulae the surveys showed up must be spiral also but that they were seen ‘edge on’ rather than ‘face on’. The spiral nature also strongly suggested to him that their complex shapes could only be maintained by motion, although he recognised that making any such measurements was hopelessly beyond his means, as they were so far away.

One enduring mystery concerning the discovery of the spiral nebulae pertains to why the  keen eye of Sir William Herschel was unable to detect them as such. It is most certainly true that the brighter spiral nebulae should have been visible in his largest telescope; the celebrated 40 foot reflector outfitted with a 49.5 inch primary speculum. One explanation, advanced by this author, may lie in Hercshel’s decision to adopt his off axis (Herschelian) design, which, as we have learned, introduced some aberrations to the images which reduced the instrument’s defining power enough to render the faint and delicate spiral arms all but invisible. Evidence in support of this comes from Herschel’s failure to detect the E and F stars of the theta Orionis complex,  as well as the fact that he almost invariably employed low powers with this instrument (much of his fine planetary work was conducted with a much smaller instrument; a conventional long focus Newtonian of 6.3 inch aperture) Yet another possibility is that Herschel may have observed such objects when his mirrors were in a more advanced state of tarnishing. In a work published by William F. Denning, we are made aware that slight tarnishing (of a silver substrate) could often be useful in improving planetary images, acting in much the same way as a modern neutral density filter, which can reduce glare and improve contrast. But this would not be the case with deep sky objects, where even slight tarnishing will apprecibaly reduce the so called “space penetrating power,” as Herschel referred to it, helping to explain why he did not see the spiral structures which were so obvious to Lord Rosse and his assistants. That said, without some form of reconstructive experimentation, we shall probably never know the precise reasons for this anomaly.

One of the most important questions still to be resolved(excuse the pun) was the nature of nebulae in general. Sir John Herschel (discussed at length in another chapter) had formed the opinion that all nebulae would eventually be resolved into stars, but Lord Rosse was more open minded about this. Telescopic scrutiny of many objects with the Leviathan, including M1 (the Crab Nebula, as coined by Lord Rosse himself), M27, M56 and M97 did not show stellar constituents, so the jury was still out concerning this question. But there was always nagging doubts that the mirror might not have been gathering the amount of light it was capable of due to rapid tarnishing in the humid, southern Irish climate. Concerning this possibility, Lord Rosse wrote:

We have had perhaps two or three specula as perfect as the first one; but the mass of observations has been made with specula considerably inferior to it, and, I am sorry to say, very often not as bright  as they should have been…..While the telescope was in constant use in all weathers, it would have been a hopeless task to attempt to keep in a state fit for the resolution of nebulae, and the attempt was not made. I may, perhaps, mention that with the 3 feet speculum in fine order I have often detected resolvability when there was no trace of it with the 6 feet speculum in its ordinary working state.

That said, Lord Rosse’s caution concerning the universality of stellar nebulae was vindicated just over two decades later, when in 1864 William Huggins employed spectroscopy to show that some nebulae were distinctly different from those of stars.

As discussed previously, Lord Rosse did not employ a finder with the telescope, relying instead on the 31 arc minute field in the ‘low power’ setting.  Oculars of various focal length were placed on an elegant sliding mechanism so that the observer could move from low to high power with little or no delay. The Leviathan was also fitted with a micrometer, the proper operation of which was a necessity for making the elaborate drawings of deep sky objects with their correct scale.

Records show that the instrument could be used about 60 nights per year, but in retrospect, it seems rather odd that Lord Rosse would choose to erect the great telescope so close to the Bog of Allen (from which the turf was derived to power the furnaces for the molten optical metal), which encouraged fog banks to form on still evenings, further reducing its utility. But at least it served to warn later generations of giant telescope makers to pay closer attention to the observing site before committing to some ambitious project. Indeed, nearly all later telescopes of grand esate were erected upon sites that were carefully field tested prior to the commencement of any building.

The great telescope and the opulent milieu in which it was erected became a Jerusalem of learning for two generations of astronomers, many of whom made their astronomical debuts observing with the great telescope. In 1852, Oxmantown hosted a meeting of the British Lunar Committee in the grounds of Birr Castle. As a general rule, Lord Rosse employed many young observers (no doubt owing to their enthusiasm for astronomical work and keen vision), who served at the telescope for a number of years before moving on to other observatories in order to further their careers. For example, Robinson served as the first Director of Armagh Observatory (a post he held until he was 90!), and a young Sir Robert Stawell Ball, who served as an astronomical assistant at Parsonstown between 1865 and 1867, as well as an academic tutor to Lord Rosse’s children, would be a future Astronomer Royal for Ireland (based at Dunsink Observatory, Dublin, between 1874 and 1892), before being appointed to the prestigious position of Lowdean Professor of Astronomy at Cambridge University in 1893. Of Lord Rosse, Sir Robert graciously observed, “personally and socially, [he] endeared himself to all with whom he came in contact.”

The distinguished Irish astronomer, Sir Robert Stawell Ball (1840 –1913), one of the great popularisers of astronomy during the Victorian Period. Image credit: Wiki Commons.

Lord Oxmantown, the third Earl, maintained an active role as an observer until failing health in the early 1860’s forced him to give up routine astronomical work, entrusting all research to the assistants whom he assiduously trained. In the summer of 1867, on the advice of his physicians, the ageing peer retired to the seaside residence of Monkstown, overlooking Dublin Bay, in the hope that the fresh, maritime air would improve his condition. But it was to no avail. He passed away peacefully on October 31 of the same year.

It was at about the same time that Lord Rosse’s eldest son (1840–1908), the fourth Earl, began to take on more of an active role in his father’s work. Born and raised in Birr, he was educated at Trinity College, Dublin, and Oxford University, before returning to Ireland to serve in various high profile roles in the administration of Ireland. Though largely considered to be overshadowed by the achievements of his father, Lawrence Parsons embraced the new technologies that were coming to the fore, having first experimented with a newly erected 18 inch reflector of ten feet focus, which was ingeniously powered by a water wheel in 1866. In the years that followed, the fourth Earl managed to construct partially successful clock drives for both the 36 inch and 72 inch telescopes.

The provision of crude clock drives on the two great telescopes enabled more sophisticated science to be performed and, in this capacity, crude spectroscopic analyses of a variety of deep sky objects was carried out. Much of this important work was carried out by a young Dane, John Louis Emil Dreyer (1852–1926), who had put down roots by marrying a lassie from County Limerick, serving as assistant astronomer at Birr between 1874 and 1878.  All the spectra obtained on the spiral nebulae were shown to be stellar in character, while all those obtained from the planetary nebulae showed quite distinctive line spectra, further advancing the notion that there were fundamental differences in the nature of nebulae.

Dreyer used the Leviathan to add a considerable number of newly discovered nebulae to the tally already discovered by his illustrious predecessors (particularly Messier and the Herschels). Many of these new objects were recorded in a catalogue compiled by the fourth Earl covering the three decades between 1848 and 1878. Another notable discovery was made by the English astronomer, Ralph Copeland (1837–1905), who served as assistant astronomer at Birr between 1871 and 1876, used the enormous light gathering power of the Leviathan to discover 35 new NGC objects, most famous of which is a grouping of seven large galaxies in Leo – Copeland’s Septet as it is known today, that include NGC 3745, 3746, 3748, 3750, 3751, 3753, and 3754.

Lawrence Parsons, the fourth Earl of Rosse (1840 –1908). Image credit: Wiki Commons.

The fourth Earl of Rosse is perhaps best known for his work in determining the surface temperature of the sunlit face of the Moon. For decades, astronomers such as Piazzi Smyth and Macedonio Melloni ( inventor of the first infrared thermopile in 1831, which transduced thermal energy into electrical energy) had wondered whether the Moon would have an equable temperature like the Earth, and to this end had carried out the first crude experiments in its determination with results which turned out to be mostly inconclusive.

Determining the temperature of the Moon is far from trivial however, as a moment’s reflection (excuse the pun once again) will reveal. Lord Rosse correctly concluded that the contribution of thermal energy from lunar vulcanism was negligible. That leaves two principal sources of heat. First, there will be that which is reflected. This will be largely independent of the temperature of the moon’s surface, but rather will depend only upon its power of reflection (its albedo). The second contributor to lunar heat is that which she emits as a consequence of her natural heat which is mainly, but not entirely, due to solar irradiance. The amount of this heat will depend upon the temperature of the Moon’s surface and its radiating power. Though the thermopile could not readily distinguish between these two sources of heat, Lord Rosse realised that they would vary differently in accordance with the development of the lunar phase, with the former increasing steadily from thin crescent and reaching a maximum at full Moon, whilst the latter ought to lag behind the former, as a consequence of the time it takes for the surface to heat up (in much the same way as daytime summer temperatures reach their maximum several hours after noon). Thus, this ‘dark’ (infrared) heat ought to be at its maximum after full Moon.

Lord Rosse begun such measurements using the 36 inch reflector in 1868 and the careful work continued for several years. His first estimates showed that the lunar surface temperature near the equator could reach 500 degrees Fahrenheit (260C), but with subsequent refinements made by his fellow physicists, he later revised this down to just over 200 degrees Fahrenheit (or about the boiling point of water at sea level). The latter measure agrees well with the modern accepted maximum value of 253 Fahrenheit.

Of course, the temperatures arrived at by Lord Rosse referred to the equator, in the middle of a long lunar day. Naturally, the further away from the equator one moves, the cooler the surface becomes. He peformed similar experiments during a lunar eclipse, when its surface is cut off from all direct sunlight. Indeed, he was able to monitor a rapid drop in lunar surface temperature as a ‘wave of cold’ moved across its surface. Indeed, he was able to record enormous temperature swings in the course of an hour. This provided further proof that the Moon is an airless world, incapable of holding onto heat as it moves from direct sunlight into darkness.

By the 1880s, the Leviathan was most definitely showing its age and many astronomers felt that its best days were well behind it. Indeed, from the late 19th century onwards the 72 inch was mostly used in sporadic observations of interesting objects. For example, on the night of September 17 1877, Lord Rosse was able to confirm the existence of the tiny Martian satellites, Deimos and Phobos, discovered by Professor Asaph Hall, just a few short months before using the great Washington refractor. The last and longest serving assistant assigned to the Leviathan was the aforementioned Dr. Boeddicker, who concerned himself with detailed visual observations of the northernly Milky Way, which culminated with an extraordinarily detailed drawing of the vast stellar archipleagos within its confines, taking him no less than five years to complete, beginning in 1885 and coming to an end in 1890. Doubtless, it was a work of outstanding artistic beauty but alas, photography was now all the rage, and as a consequence, its significance was of questionable scientific value. And while the venerable 36 inch was now equatorially mounted with a smootly operating clock drive, and even in the hope that it might be used as an astrograph, the declining relevance of the antiquated Leviathan weighed heavy on the fourth Earl’s mind:

Can the pencil of the draughtsman be any longer profitably employed upon nebulae as seen through the 6 foot reflector when photography, to say the least the least, follows so closely on his heels?

The metal mirrors making up the telescopes of the Rosse estate were possibly as good as they could be, but new technology made them living dinosaurs. In particular, the advent of much lighter silver on glass mirrors rendered the construction of large, observatory class reflectors much more easy to fashion, owing to their vastly reduced mass and higher reflectivity. In addition, glass substrates, with their lower thermal coefficients of expansion (and, to a lesser degree, their higher specific heat capacities) than the old speculum metals rendered them considerably less sensitive to small changes in temperature, allowing more stable images to be maintained in the course of a night’s work.

Lord Rosse passed away on August 30 1908 and with him all work with the Leviathan of Parsonstown ceased. With his brothers becoming the executors of his estate, the great telescope was dismantled  because of growing concerns that it had become a working concern. In 1912, the 6 foot mirror was removed and despatched to the Science Museuem in London for preservation. The 36 inch was also left idle. Dr. Boeddicker, remained in the employ of the fifth Earl, though not it seems, in a scientific capacity. He was entrusted with gathering together the historical archives of the family. And when the First World War broke out in 1914, Boeddicker, a native of Germany, was considered an enemy of the state (which was still under British rule) and was forced to return to his own country. He died aged 84 in 1937, under Hitler’s Third Reich.

The next decade of Irish history proved very turbulent, with the result that the Rosse family had to leave the castle for extended periods of time. By the time the political climate settled down in the late 1920s, the great infrastructures that once boasted the largest telescopes on the face of God’s Earth were in a very sad state of delapidation, though according to Sir Charles Parson, the 36 inch was ‘nearly intact’ as late as 1927. That said, it’s whereabouts today is unknown.

One of the original 72 inch speculum mirrors used in the Leviathan, now housed in the Science Museum, London. Image credit: Wiki Commons.

 

A final twist in the story of the Leviathan occurred after a TV programme, lecture, and book by the late Sir Patrick Moore appeared on the great telescope in the 1970s. This resulted in a renewed interest in the 72-inch telescope, with the restoration of its wooden tube between 1971 and 1975, and soon it became a tourist attraction. But it was not before the 1990s that plans to actually rebuild the telescope came to fruition. In 1994, the retired structural engineer and amateur astronomer, Michael Tubridy, was commissioned to research and re-design the Rosse Leviathan. Unfortunately, the original plans were lost, and so it took a considerable amount of detective work which included re-examining the remains of the telescope, together with old observing logs and contemporary photographs taken by Mary Rosse, wife of the 3rd Earl. Reconstruction work lasted from early 1996 until the beginning of 1997. It had been planned to include a working mirror, but owing to budget constraints, this had to be left for a separate project.

A faithful rainbow appearing over the reconstructed Leviathan, in the modern  grounds of Birr Castle. Image credit: Wiki Commons.

 

 

 

 

 

 

 

 

 

 

The new mirror was installed in 1999. Unlike the speculum original, and in a historically respectful departure from modern aluminium- or silver-coated glass mirrors, the replica was cast from solid aluminium, thus acting as a compromise between authenticity and utility in astronomical observation.

The great technical achievements of the Rosse family,  their friendship to the people of Ireland, as well as to the wider international astronomical community, will not easily be erased from memory. Once the brain and glory of all that was held dear in astronomical enquiry, their telescopes continue to be remembered in the mind’s eye as emblems of the indefatiguable spirit of the human imagination; to peer farther into space than anyone had ever seen before; to bring the heavenly creation closer to the earth, as well as to understand something more of its mysteries. And we’ve been doing that ever since.

References & Links

Mollan, C., William Parsons, 3rd Earl of Rosse: Astronomy and the Castle in Nineteenth-century Ireland (Royal Dublin Society – Science and Irish Culture), Manchester University Press, 2014.

Moore, P., The Astronomy of Birr Castle, Quack Books, 1992.

King, H.C., The History of the Telescope, Dover, 1955.

Ball, R.S., The Story of the Heavens, Casell, 1893.

Denning, W. F., Telescopic Work for Starlight Evenings (1891), HardPress Publishing, 2013.

Bell, L. The Telescope (1922), HardPress Publishing, 2013.

Professor Paul Callanan of University College Cork, explains the significance of Lord Rosse’s Leviathan.

Some History of Birr, Ireland.

Links to historical works on the subject of the astronomy of Lord Rosse and Birr Castle.

More about Birr Castle for the Astronomical Tourist.

 

Read more about the telescopes and personalities that inspired four centuries of telescopic astronomy in my up and coming book, Astronomy Tales from the Golden Age.

 

 

 

 

De Fideli.