Beginner Telescopes

 

The ShortTube 80: ready to go to work.

In this age we live in, choosing a good beginner telescope can be a daunting task, what with all the models that are flooding the market. In this article, I  would like to discuss the potential of several telescopes that offer good value for money and will allow their owners to grow in the hobby.

 

Tune in soon for details…………………..

 

De Fideli.

A Brief Commentary on the Holy Scriptures; Tree of Life Version(TLV).

Seeing Scripture through Jewish eyes.

A song: a psalm of Asaph.
God, do not keep silent.
Do not hold Your peace, O God.
Do not be still.
For look, Your enemies make an uproar.
Those who hate You lift up their head.
They make a shrewd plot against Your people,
conspiring against Your treasured ones.
“Come,” they say, “let’s wipe them out as a nation!
Let Israel’s name be remembered no more!”
For with one mind they plot together.
Against You do they make a covenant.

                                                                                                                        Psalm 83: 1-5

 

Are you looking for a brand-new Bible experience? Are you searching for a translation of the Bible that restores some of the Hebrew names and terminology found in the original manuscripts? Perhaps you are looking for a Bible that will help you rekindle an interest in the sacred words of Scripture seen from a Messianic Jewish perspective? If so, I have just the recommendation for you; enter the Tree of Life Vesion(TLV).

The brain child of this ambitious project was Daniah Greenberg and her Rabbi husband, Mark Greenberg, who assembled a cadre of Messianic Jewish Bible scholars to create an all-new translation of the Holy Scriptures that gives the reader a solid flavour of the original Hebraic overtones of the Bible, with a decidely Jewish accent. But it was no small feat, given the proliferation of English Bible versions flooding the global market. Daniah had the courage and conviction to raise the funds to pay for soild scholarship within the Jewish cultural tradition, which culminated with the first edition of the TLV Bible in 2011. Daniah Greenberg now serves as President of the Messianic Jewish Family Bible Society. Greenberg is also CEO of the newly established TLV Bible Society.

It pays to remember that all the Biblical writers, with the possible exception of the author of the Book of Job, were Jews. Jesus Christ was Jewish. The earliest Christian meetings took place in synagogues and despite the attendant evils of anti-semitism throughout history, and its giving rise to unbiblical ideas such as replacement theology,  it is undoubtedly the case that unique insights into much of the Biblical narrative has come from the Jewish mindset. Seen in this light, it is not at all surprising that a new Bible translation made by the original people to which the Lord of all Creation first appeared should find a place on the bookshelves of many Christians in the 21st century.

The first thing you will notice about the TLV is the unfamiliar ordering of the books of the Bible, which have been re-presented in the order rendered in the Jewish tradition, which Christians refer to as the Old Testament. In Jewish parlance, these are the books of the Tanakh.

As you can see from the table of contents below, the Tanakh is further divided into three sections; the Torah (Law of Moses or Pentateuch), the Neviim (The Prophets) and the Ketuvim (The Writings).

 

The unique ordering of the books of the Old Testament(Tanakh), as experienced by Orthodox Jews.

The books of the New Testament(Good News) are presented in their traditional order. The reader will note that the Book of James is titled ‘Jacob,’ and Jude is titled ‘Judah, which  represent their transliterated Jewish names.

The New testament books are presented in their traditional order, with two transliterated names, Jacob(James) and Judah(Jude).

A sizeable number of words are presented in the original Hebrew. For example, YHWH God’s covenant name, is often referred to as Adonai,  but also as Elohim (Creator). Jesus is denoted as Yeshua, Mary(the mother of Jesus) is given her original name, Miriam; Spirit is presented as Ruach, the Levitical priests, Kohanim, the children of Israel, B’nei-Israel and Sabbath is translated as Shabbat. All Hebrew terminology can be referenced at the back of the Bible in the form of a tidy glossary. There is even a section which helps the reader pronounce these Hebrew words correctly. That said, once you get into the TLV, most of the terms sink in very easily and naturally and so provide the reader with an education in basic Hebrew religious terminology. The addition of original Hebrew words also adds to the poetic beauty of the language of the Scriptures, which are readily appreciated while reading through.

Each book of the Holy Scriptures is accompanied by a short introduction written by Messianic Jewish scholars, which provides a concise overview of the most important ideas developed in the texts. The translators intentionally chose to produce a translation that is at once respectful to more traditional translations of the Bible such as the Authorized King James Version (KJV), and more modern translations such as the English Standard Version (ESV) and New American Standard Bible (NASB), retaining some classic Biblical terminology such as “Behold“, “lovingkindness” and “Chaldeans.” For example, in the opening verses of the Book of Esther, the TLV refers to the Babylonian King as Ahasuerus and not Xerxes ,as you will find in looser translations such as the NIV and NLT.

This is what happened in the days of Ahasuerus, the Ahasuerus who reigned over 127 provinces from India to Ethiopia.

Esther 1:1

In keeping with the original customs of the first Christians, the word ‘baptism‘ does not appear in the TLV, being replaced by the more appropriate term, ‘immersion.’ This is entirely justified as infant baptism was not practiced by the earliest followers of Yeshua. Consider this passage from Acts 2;

Peter said to them, “Repent, and let each of you be immersed in the name of Messiah Yeshua for the removal of your sins, and you will receive the gift of the Ruach ha-Kodesh.

Acts 2:38

John the Baptist is likewise referred to as “John the Immerser”

Unlike virtually all other Bibles in the English language, the Adversary’s name is presented in lower case, ‘the satan‘; a most appropriate demotion to honour the ‘father of lies.’ Consider, for example, the opening passages of the Book of Job:

One day the sons of God came to present themselves before Adonai, and the satan also came with them.  Adonai said to the satan, “Where have you come from?”

The satan responded to Adonai and said, “From roaming the earth and from walking on it.

Adonai said to the satan, “Did you notice my servant Job? There is no one like him on the earth—a blameless and upright man, who fears God and spurns evil.”

Job: 1:6-8

Another interesting aspect of the TLV is that it quite often departs from the usual preterite, or imperfect tense one normally experiences in traditional translations. Consider this passage from the Gospel of Matthew Chapter 4 in the NASB:

Again, the devil took Him to a very high mountain and *showed Him all the kingdoms of the world and their glory;

Matthew 4:8

Now consider the same passage in the TLV:

Again, the devil takes Him to a very high mountain and shows Him all the kingdoms of the world and their glory.

Matthew 4:8

These occasional departures add to the immediacy of the situation as if it were happening right now! This is a powerful linguistic tool that the TLV scholars used to evince the poignancy of certain passages of Holy Scripture.

The poetic books of the Holy Scriptures, such as the Psalms, are most beautifully rendered and retain traditional  terms like Selah (an uncertain word thought to refer to an interlude in a musical performance). Consider, for example, Psalm 24 in the TLV:

A psalm of David.
The earth is Adonai’s and all that fills it—
the world, and those dwelling on it.
For He founded it upon the seas,
and established it upon the rivers.
Who may go up on the mountain of Adonai?
Who may stand in His holy place?
One with clean hands and a pure heart,
who has not lifted his soul in vain,
nor sworn deceitfully.
He will receive a blessing from Adonai,
righteousness from God his salvation.
Such is the generation seeking Him,
seeking Your face, even Jacob! Selah
Lift up your heads, O gates,
and be lifted up, you everlasting doors:
that the King of glory may come in.
“Who is this King of glory?”
Adonai strong and mighty,
Adonai mighty in battle!
Lift up your heads, O gates,
and lift them up, you everlasting doors:
that the King of glory may come in.
“Who is this King of glory?”
Adonai-Tzva’ot—He is the King of glory! Selah

Psalm 24

 

The reader of the TLV Holy Scriptures will note that the word “church” does not appear in this translation. Instead, the scholars chose to use the words “Messiah’s community.” This is an acceptable change, as the word they were probably translating was the Greek term ecclesia, which appears in the New Testament 115 times and was often associated with a civil body or council summoned for a particular purpose. The nearest the Greek language gets to “church” is kuriakos, which is best understood as “pertaining to the Lord,” which probably morphed into the Germanic “Kirche” or “Kirk,” which is still used in northern England and Scotland to this day.

An amusing aside: Has anyone ever referred to Kirk Douglas as ‘Church Douglas’, who just happens to be an orthodox Jew?

These translative nuances matter little in the scheme of things however. Acts 11 provides a good illustration of these translation choices:

Then Barnabas left for Tarsus to look for Saul, and when he had found him, he brought him to Antioch. For a whole year they met together with Messiah’s community and taught a large number. Now it was in Antioch that the disciples were first called “Christianoi.”

Acts 11:25-26

Note also that the TLV translation team used the Greek term for Christians, ‘Christianoi‘. This is also perfectly acceptable, as there was no Hebrew word for ‘Christian’ in those early days.

The scholars who created the TLV chose to use the latest manuscript evidence, which included much older texts found in the modern era compared with the King James or New King James, for example(which are based on the Textus Receptus). It thus follows a similar translation ethos to other popular Bibles in the English language such as the NIV and ESV.  On the spectrum of modern English Bible translations, which vary from the highly literal, so-called ‘word for word’ renderings, through the less literal ‘thought to thought’ translations, I would categorise the TLV as adopting a ‘middle of the road’ approach. Perhaps the best way to illustrate this is to look at the same passage of Scripture in a few translations. Consider, for example, the highly literal NASB rendition of Matthew 9, verses 1 through 8:

Getting into a boat, Jesus crossed over the sea and came to His own city. And they brought to Him a paralytic lying on a bed. Seeing their faith, Jesus said to the paralytic, “Take courage, son; your sins are forgiven.” And some of the scribes said to themselves, “This fellow blasphemes.” And Jesus knowing their thoughts said, “Why are you thinking evil in your hearts? Which is easier, to say, ‘Your sins are forgiven,’ or to say, ‘Get up, and walk’? But so that you may know that the Son of Man has authority on earth to forgive sins”—then He said to the paralytic, “Get up, pick up your bed and go home.” And he got up and went home. But when the crowds saw this, they were awestruck, and glorified God, who had given such authority to men.

Matthew 9:1-8(NASB)

 

Next consider the TLV equivalent:

After getting into a boat, Yeshua crossed over and came to His own town. Just then, some people brought to Him a paralyzed man lying on a cot. And seeing their faith, Yeshua said to the paralyzed man, “Take courage, son! Your sins are forgiven.” Then some of the Torah scholars said among themselves, “This fellow blasphemes!” And knowing their thoughts, Yeshua said, “Why are you entertaining evil in your hearts? For which is easier, to say, ‘Your sins are forgiven,’ or to say, ‘Get up and walk’? But so you may know that the Son of Man has authority on earth to pardon sins…” Then He tells the paralyzed man, “Get up, take your cot and go home.” And he got up and went home. When the crowd saw it, they were afraid and glorified God, who had given such authority to men.

Matthew 9:1-8(TLV)

 

Finally, consider the same passage from a thought for thought translation like the NIV:

Jesus stepped into a boat, crossed over and came to his own town. Some men brought to him a paralyzed man, lying on a mat. When Jesus saw their faith, he said to the man, “Take heart, son; your sins are forgiven.” At this, some of the teachers of the law said to themselves, “This fellow is blaspheming!” Knowing their thoughts, Jesus said, “Why do you entertain evil thoughts in your hearts? Which is easier: to say, ‘Your sins are forgiven,’ or to say, ‘Get up and walk’?  But I want you to know that the Son of Man has authority on earth to forgive sins.” So he said to the paralyzed man, “Get up, take your mat and go home.” Then the man got up and went home.  When the crowd saw this, they were filled with awe; and they praised God, who had given such authority to man.

Matthew 9:1-8(NIV)

I think it is reasonable to conclude that the TLV is a good compromise between both translation philosophies, distinguishing itself by means of introducing some Hebrew words and names but also in the way that the translators have chosen to alter the tense of some passages, as discussed previosuly.

The TLV  also follows many of the newer Bible versions in adopting a more gender neutral approach to terms such as ‘Brethern’ or ‘Brothers’. For example, the TLV renders Galatians 1:11 thus:

Now I want you to know, brothers and sisters, that the Good News proclaimed by me is not man-made.

Galatians 1:11 (TLV)

Compare this to the more conservative ESV:

For I would have you know, brothers, that the gospel that was preached by me is not man’s gospel.

Galatians 1:11 (ESV)

And the NIV:

I want you to know, brothers and sisters, that the gospel I preached is not of human origin.

Galatians 1:11(NIV)

Some commentators have expressed concern that the Bible should never be altered so as to express political correctness, as in this case, where ‘brothers’ is altered for the sake of inclusiveness to read, ‘brothers and sisters.’ I understand their concerns but I have no strong opinion either way on this issue, so long as the context of the particular verse is not altered.

The TLV does have a couple of errors which I picked up while reading through the translation. The first appears in Jeremiah 34:14

At the end of seven years you are to set free every man his brother that is a Hebrew who has been sold to you and has served you six years; you are [to] let him go free from you.’ But your fathers did not obey Me, nor inclined their ear.

I have inserted the missing word in bold brackets that makes the sentence comprehensible.

In addition there is a printing error in my Large Print Personal Size TLV on page 902 and 903, the heading of which reads “Obadiah 9” and “Obadiah 1,” respectively. Since these headings are meant to illustrate the chapter numbers, they are clearly unecessary as the Book of Obadiah only has a single chapter.

The typographical error niggled me at first (as an avid reader, I’m very tolerant of typos in general but view Holy Scripture in a more exalted light), but I understand that these things happen. I have written to the TLV Bible Society informing them of these issues which I hope they will be able to resolve in due course.

Some comments on the physical presentation of the TLV Holy Scriptures

The author’s TLV large print copy of the Holy Scriptures.

I was very impressed with the quality of the giant print personal size TLV that I acquired back in January 2018. It has a beautiful leathertex cover, which is soft and durable. Indeed, the current selection of faux leather Bibles(in many translations)are amazing value for money, and are superior to the cheap, bonded leather found on premium Bibles just a decade ago. The TLV also has a smyth-sewn binding for greater durability even with prolonged use.

The Personal Size Giant Print TLV is about 9 inches long and 2 inches thick.

It has a paste-down liner, a highly readable 12.5 font size, beautiful gold gilded pages and comes with a single ribbon marker. I especially like the paper used by Baker Books(the publisher of the TLV), which is a more creamy white than the usual white pages seen n many other of my Bibles.As seen below, the text is presented in a double column format and has a generous number of cross-references. The text is line matched and shows minimal ghosting, which annoys some people more than others.

The paper in the TLV is an off white(creamy), the text is double columned, shows little bleed-through, with clear 12.5 sized font.

The back of the TLV has an extensive concordance, a short glossary explaining the Hebrew terms used in the translation, as well as a short section of prayers (including the Aaronic benediction and the Lord’s Prayer) and other  blessings for those who wish to learn a little more Hebrew. A couple of maps show Yeshua’s travels in the 1st century AD as well as a modern map of Israel. Best of all, you can acquire all of this for a very modest price: I paid about £25 for my copy but you can also get it at discounted prices from smaller retailers. See here for just one example.

I would highly recommend the TLV to avid readers of the Bible. It will come in especially handy when witnessing to Jews but can be enjoyed by anyone who appreciates the deep Hebrew roots of the Christian faith.

 

Dr Neil English shows how the Christain faith has inspired visual astronomers over the centuries in his new historical work; Chronicling the Golden Age of Astronomy.

 

Post Scriptum: You can also read the TLV(or indeed any other Bible translation) online by visiting BibleGateway.com

 

De Fideli.

In Praise of Barlow Lenses.

Three fine, low-cost shorty Barlows, ideal for use with my Newtonian reflectors. From left to right: the Meade 3x, the Orion shorty Barlow 2x and the Astroengineering 1.6x Barlow.

In this day and age, where almost every item of equipment we use under the stars is taken for granted, it pays to remember that we have a lot to thank our astronomical forebears for. A case in point is the humble Barlow lens, which has enjoyed a very long and illustrious history with visual observers, where today it remains an indispensable tool as well as a cost-saving device for the amateur astronomer.

Contrary to popular belief, the concept of the Barlow lens does not reside entirely with the musings of the English mathematician Peter Barlow (1776-1862), but actually had its origination in the fecund mind of the 18th century German philosopher and mathematician, Christian Wolff (1679-1724), who first conceived of the idea of adding a concave lens ahead of the eyepiece but behind the objective of a telescope  in order to provide greater magnification and with a slight increase in focal length. The result had mixed fortunes however, in that the resulting images in an achromatic telescope, while certainly enlarging the image, also deteriorated the achromatism achieved by the combination of the crown & flint object glass.

Charistian Wolff(1679-1724) : the originator of the Barlow lens concept in the 18th century. Image credit; Wiki Commons.

The problem was once again studied with renewed vigour in the first half of the 19th century, when Peter Barlow, then a Professor of mathematics at the Royal Military Academy, Woolwich, England, computed the design of an achromatic concave lens which was made by the optician, George Dollond, and mounted in a telescope where it showed very promising results. Some of the earliest ‘guinea pigs’ to experiment on the new device included the Reverend William Rutter Dawes and the Admiral William H. Smyth, who both commented favourably on the new contraption as early as the late 1830s and early 1840s, reporting that the image was left just as colour free as when the telescope was used without the contrivance, even allowing them to vary the magnification at will by moving the doublet lens either towards or away from the ocular lens.

The device, now commonly known as the Barlow lens, enjoyed rapid success. This author is reminded of the work of the astronomers serving in the employ of the Victorian tycoon, George Bishop, who had set up a lavishly-equipped private observatory in 1836 at South Villa, Inner Circle, Regent’s Park, London, where the Barlow lens is vividly described:

An achromatic lens( the macro-micro lens), which slides into the tube of the micrometer, was frequently used by Mr. Dawes in his observations of double stars. The effect of the interposition of this lens is to increase the magnifying power nearly in the ratio of two to one, without any very serious diminution of light. It is, therefore, of great service in the measurement of difficult objects which require increase in power with considerable light.

xii-xiii Bishop, G., Astronomical Observations Taken at the Observatory , South Villa, Inner Circle, Regent’s Park, London, During the Years 1839-1851

How does a Barlow work? Because it is a negative(diverging) lens consisting in its most basic form as either an air-spaced or cemented crown-flint doublet, it changes the angle of convergence, making it longer, as though the beam were coming from an objective lens or primary mirror with a longer focal length. What this means in effect is that a 2x Barlow will double the effective f ratio of your telescope, turning an f/5 system into an f/10. And though the Barlow lens can introduce some additional errors into the optical train, if well made, it will almost certainly remove more aberrations than it generates. This is easy to see when using an ordinary eyepiece, such as a 20mm Plossl or some such, in a fast optical system like my two Newtonian reflectors. Used without a Barlow lens, the 20mm Plossl will give very good on-axis performance but less so off-axis. Now insert a 2x Barlow lens ahead of the eyepiece and the off-axis performance is considerably improved! That’s because the cone the eyepiece ‘sees’ looks like an f/10 optical system and not an f/5 system.

In the days before anti-reflection coatings, Barlow lenses caused a small but noticeable reduction in image brightness, as well as the odd ghost image due to internal reflections, especially on bright objects, but with modern multi-coatings appplied to all air-to-glass surfaces, this light loss is reduced to negligible levels(~3 per cent).

Barlows come in all shapes and sizes, offering magnification boosts in the range of 1.6x right up to 5x. That said, by far the most commonly used Barlow lenses offer powers of either 2x or 3x. In general, longer Barlow lenses tend to give greater magnification boosts than shorter ones, but there are always exceptions.What is more, the power printed on the barrel may not be the power you get in field use, but it’s normally quite close. In addition, with refractors that employ 90-degree star diagonals, a 2x Barlow used in normal mode can also give a 3x boost if screwed into the front of the same diagonal. Bear in mind though that most modern Barlow lenses are intended for use at the power they show on the barrel and may not perform quite so well when moved to provide a different magnification. One should always avoid models offering a range of magnifications by moving the optics in a sliding tube, for example.

The Barlow lens has the inherent property of increasing the eye relief of any eyepiece used in combination with it. This is of considerable advantage to those who enjoy very short focal length Plossl and orthoscopics, for example, which by nature offer amounts of eye relief broadly similar to the focal length of the ocular used and thereby improving the degree of viewing comfort experienced by the observer.

With my fast (f/5) Newtonian telescopes, I have found through experience that shorty Barlows are better than their longer counterparts, because they always reach focus with them.That said, shorty Barlows also increase eyerelief more than longer Barlows. I have used this to great effect in my study of double stars with a 130mm f/5 and a much larger 305mm f/5 Newtonian. For example, when combined with one of my favourite eyepieces used to resolve close binary systems; a Parks Gold 7.5mm ocular, a 3x Meade shorty Barlow provides a supremely comfortable field of view at 260x in the 130mm telescope with wonderful, edge-to edge-sharpness.

Another favourite with a Barlow lens is my old 4.8mm T1 Nagler. This high power eyepiece delivers a magnification of 135x in the 130mm f/5 by itself but the eye relief is quite tight. All that changes though when I use it in conjunction with my 2x or 3x Barlow lenses (yielding powers of 270x and 405x, respectively). Eye relief is much improved and the views that little bit more enjoyable!

When Barlowing longer focal length eyepieces, care must be taken to ensure it does not strongly vignette the outer part of the eyepiece field. If the field stop of the eyepiece is greater than the clear aperture of the Barlow, then it will cut off some of the light coming from the outer sections of the eyepiece, resulting in significant light loss and a reduction in the true field presented. Look at the two Barlows shown in the image below, for example. The Barlow shown on the left is the Orion 2x shorty Barlow and the one on the right is the 3x Meade Barlow. Note the larger clear aperture of the former, which makes it better suited for magnifying low-power, long focal length oculars.

The 2x Orion Shorty Barlow(left) is better suited to boosting the power in long focal length eyepieces.

In recent years, a number of firms have brought to market so-called “apochromatic” Barlow lenses with some kind of low dispersion glass included in the prescription. These can often be sold at higher prices than regular, “achromatic” Barlow lenses with the implication that they will perform better. This is nonsense however, as a good achromatic doublet with properly applied anti-reflection coatings will give essentially the same performance. Indeed, one of the first ‘apo’ Barlows this author has experienced; the Meade # 140; performed significantly worse in field tests than a standard achromatic system costing half as much! The truth of course, is that the introduction of apochromatic Barlows is yet another clever marketing gimmick that has caught more than a few tyros off guard. As proof of concept, consider the excellent Barlow lenses long offered by well established firms such as TeleVue, who make some of the best long Barlows money can buy. You won’t have to look long to see that all of the Barlows Albert Nagler has brought to market are well-made achromatic doublets. If there were an advantage of including low dispersion glass in their prescription, don’t you think Uncle Al would have done it long ago?

Nor will a Barlow lens improve the colour correction of an achromatic refractor, as some amateurs have claimed on the vulgar forums. The dispersion caused by the achromatic doublet is completely unchanged when using a Barlow lens. Neither will it increase the depth of focus of the telescope when used normally. That said, Barlows can certainly help achieve larger fields that are corrected for the Seidel aberrations such as coma, for example, which can be mildly annoying to those who use fast f/4 and f/5 relative apertures.

Consider a case in point: the coma free field of a Newtonian system in millimetres, scales directly as the cube of focal ratio. Specifically;

The coma free field = 0.022 x f^3.

So, for my f/5 Newtonian we obtain a coma free field = 0.022 x 5^3 = 2.75mm.

Next, consider how this translates into true field.

True field in radians is given by; coma free field/ focal length.

Thus, the true coma free field in the 650mm Newtonian will be:

(2.75/650) = 0.0042 radians, and then converting to angular degrees gives 0.0042 x 360/2pi = 0.24 degrees.

Consider next a typical high−power eyepiece used in double star divination. As mentioned above, one of my favourite combinations for close double star work is a 7.5mm Parks Gold coupled to a 3x Barlow lens, with an apparent filed of view of about 50 degrees. This yields a power of 260 diameters in the 130mm f/5, so the coma free field at this enlargement is: 260 x 0.24 = 62.6 degrees!

This means that there is no coma to worry about across the entire field of view using this particular configuration. Barlows will similarly reduce the effects of other Seidel aberrations in similar fashion(though to a varying degree corresponding with how those said aberrations fall off with focal ratio). This helps keep the images of the stellar disks nice and crisp as they move from one side of the telescopic field to the other.

Barlow lenses are cost-saving devices too. Indeed, a savvy telescopist can dispense with acquiring  a complete set of half a dozen eyepieces say, and instead choose just two or three oculars and a Barlow lens(or two) to achieve the range of magnifications one desires from the telescope. For example, if you have a 25mm and 8mm Plossl, as well as a 2x Barlow used with a telescope with a focal length of 800mm, you can get a nice range of powers;  32x, 64x, 100x and 200x.This is especially true since good Barlow lenses can be had for considerably less money than a fixed focal length eyepiece. My own Barlow lenses cost between £20 and £30 and perform handsomely with virtually all eyepieces I couple them to.

For those folk who dislike the change in eye relief caused by a Barlow lens they should consider telecentric devices like those marketed by TeleVue( the Powermate) and Meade. These will not increase the eye relief you get with a given ocular and also maintain the same focus position one enjoys when the eyepiece is used alone. They are however, considerably more expensive than regular Barlows.

Barlows also have a very important role to play in astro-imaging, particualrly high-resolution lunar and planetary photography, where they provide very effective focal length boosts and thus an appropriate image scale. They are also supremely useful in binoviewing, by decreasing the amount of in-focus travel necessary to achieve focus with many of these devices.

So, in summary, Barlow lenses serve as very important tools for the modern visual observer and imager alike, and are thus very unlikely to go out of fashion any time soon. Good ones can be had fairly inexpensively and will provide the user with a lifetime of applications.

 

Neil English is author of Choosing and Using a Dobsonian Telescope.

 

 

 

De Fideli.

For the Record: My Telescope & Binocular Collection.

Duodecim:

Duodecim: 12″ f/5 Newtonian.

12″ f/5 Revelation Dobsonian with ultra-high reflectivity coatings on original mirrors, 23 per cent central obstruction. Used regularly.

 

Octavius:

Octavius; optimus.

8″ f/6 Skywtacher Dobsonian wth ultra-high reflectivity coatings on both mirrors. Original Skywacher primary mirror, original secondary replaced by a 44mm semi-major diameter unit from Orion Optics, UK. 22 per cent central obstruction. Now retired to garden.

 

Plotina:

Plotina: 130mm f/5 Newtonian reflector.

130mm f/5 Newtonian reflector, with ultra-high reflectivity coatings, secondary mirror replaced by a slightly smaller (26.9 per cent central obstruction) by Orion Optics UK. Most frequently used grab ‘n’ go telescope.

 

Tiberius:

Tiberius: 5″ f/12 neoclassical achromat refractor.

5″ f/12 IStar sourced neo-classical refractor with R 30 objective. Subject of much former work. Now retired to garden.

 

Gaius:

Gaius, my 80mm f/5 short tube achromat.

80mm f/5 ShortTube achromatic refractor. Skywatcher objective in Opticstar tube assembly. This is the subject telescope of a new book dedicated to the ShortTube 80.

 

The Traveler:

The AstroPhysics Traveler; 80mm f/11 doublet achromat.

80mm f/11 Astrophysics labelled achromatic refractor. Orginally donated to local school but returned to me after it was found in a sad state of neglected use. School instrument replaced by a smaller, shockproof instrument. Now seeking a new home.

 

Achromatic Binoculars:

9 x 28mm roof prism Pentax DCF LV pocket binocular (2009 vintage).

The Pentax DCF 9 x 28mm LV pocket binocular.

 

8 x 42mm Barr & Stroud Savannah roof prism  super wide angle. Most used, general purpose binocular.

The Barr & Stroud 8 x 42 wide-angle binocular

 

10 x 50mm Barr & Stroud Sierra roof prism. General purpose, astronomy binocular.

The Barr & Stroud 10 x 50 roof prism binocular.

 

Pentax PCF 20 x 60 WP II: Large porro prism instrument, used on a monopod for specialised deep sky observing/solar viewing.

Pentax 20 x 60 PCF WP II porro prism binocular.

 

Future plans: converting my two Newtonian telescopes in active use to binoviewing mode. Currently investigating options.

 

De Fideli.

Resolving Close Double Stars in a 12″ f/5 Dob during Cold Winter Weather.

Doudecim: the author’s 12″ f/5 Dob with a 8 x 50 achromatic finder astride.

 

Description of the Instrument:

Revelation Dobsonian, 305mm aperture with a focal length of 1525mm ( f/5)

Secondary mirror: 70mm minor axis, corresponding to a central obstruction of 22.9%

Primary and secondary mirror origin:  GSO

Primary mirror thickness(measured): 36mm (1.5″)

Mirror cell design: 9 point floatation system.

Both primary and secondary mirrors re-coated with enhanced HiLux coatings each with 97 per cent reflectivity.

Tube: Rollled aluminium, internally lined with a thin layer of cork and overlaid with standard flocking material.

Focuser: 2 speed Crayford style

Length of acclimation from room temperature to ambient: ~2 hours.

Fans used: none.

Finder: standard, straight-through  Revelation 8 x 50 model.

Method of collimation: collimation cap and Chesire eyepiece, verified with Hotech laser collimator.

Time required for precise collimation: 2 minutes.

Introduction:

The reflecting telescope reigns supreme in the 21st century as the telescope of choice for serious students of nearly all disciplines of amateur and professional astronomy. The reason is simple; in the case of Newtonians in particular,  they are, far easier to fabricate and mass produce than any other kind of telescope on the market, and are offered at sensible prices, allowing many people to fruitfully engage with the hobby. Today, an amateur can acquire a truly large telescope thanks to great advances in material science, where a thin layer of aluminium is vacuum deposited onto a carefully figured parabolic glass substrate, avoiding the problem of chromatic and spherical aberrations almost completely.

These days, it is not uncommon for an amateur to own extremely large aperture reflectors – in the 12 to 30 inch aperture class – at prices that don’t cost the earth. The development of the refractor, in contrast, has been severely retarded by the great difficulty and huge expense in producing optics of even moderate aperture. How many amateurs own an 8, 10 or 12 inch refractor? A little researching will soon reveal that very few of us would be willing to shell out the relatively enormous sums of money demanded by the few opticians willing to make them and even professional astronomers would laugh at the suggestion of replacing a large Newtonian or Cassegrain reflector to fund the installation of say a 10 or 12-inch ‘state-of-the art’ apochromat. As a case in point, this author vividly remembers an especially zealous refractor nut who openly called for the alumni of Universities to fund the installation of one such refractor. Not surprisingly, his clarion call fell on deaf ears.

Folk ain’t stupid.

While the Newtonian reflector has deservedly enjoyed a huge following from dedicated planetary and deep sky observers, their use in double star study has been artificially stunted by three decades of nefarious propaganda, instigated by individuals who clearly have little clue about how they behave when properly adjusted and acclimated. Like I said before, it’s easy to get a small refractor to ‘beat’ a large Newtonian if the latter is not adjusted correctly or has not been given enough time to cool down to ambient temperatures, but that hardly constitutes a fair test. Worse still, a subsection of the amateur community dismiss the Newtonian merely because they don’t look as ‘sexy’ as a long, slender refractor. Such individuals have reduced the hobby to something more akin to pornography than anything else. And you don’t have to look long to find it; check out the hysteria over this peashooter, for example. Has anyone not told them that a good 130mm f/5 or 6″ f/8 Newtonian would leave it in the dust, and for about half the price? Like moths to a lamp, they always seem to attract the same motley crew.

As a keen student of the history of astronomy, I have come across many cases where large Newtonian reflectors were used productively to pleasurably observe, or in some cases, even discover new double and multiple star systems. One need only look at the work of such luminaries as Sir William Herschel, Warren De la Rue, Sir William Lassell, the Reverend T.W Webb, William Denning and T.H.E.C. Espin, to name but a few, to see that the Newtonian reflector has been a very productive telescope in the divination of double stars, both for pleasure and for scientific gain. The archives of these historical figures reveal many extraordinary feats of resolution achieved with the Newtonian telescope.  And it is to these individuals that this author has turned to for guidance and inspiration.

Having left the world of small refractors behind, apart from my fabulous achromatic binos and my little ShortTube 80, I set out on an ambitious program of field testing Newtonian reflectors of ever increasing size, having gained intimate experience with the behaviour of the said telescopes in the 3, 5 and 8 inch range, firmly establishing that they are excellent double star instruments. What is more, this author has found through his own experience that a good 8 inch f/6 Newtonian reflector is a much better double star telescope than an optically excellent long focus classical refractor of 5 inch aperture and f/12 relative aperture.

These personal discoveries have led me to more closely investigate the performance of an even larger Newtonian reflector, a standard 12-inch f/5 Dobsonian, which has not enjoyed nearly as much field use than it should have since it was first acquired a few years ago. The limelight was firmly stolen by the smaller instruments, which are easier to deploy in the field, acclimate faster and are less sensitive to the vagaries of the atmosphere, but no more so than with a refractor, or indeed, any other kind of telescope, of the same size. That being said, I have enjoyed many wonderful nights where the traditional bugs that attend Newtonians were either minimal or non-existent, allowing me to obtain truly spectacular views of a suite of double stars traditionally considered ‘tricky’ by my astronomical peers.

In this capacity, this short blog will exemplify the techniques used and the results obtained in observing double stars with such a large, fast telescope.

Method:

What follows is a report of one night- January 8 2019 – between 22:00 and 23:10 UT

Ambient temperature: 0C at 22:00 UT falling to -1C by the end of the vigil at 23:10UT

Conditions: Slightly hazy, no wind, steady atmosphere (Antoniadi II), very cold.

The telescope was brought out from a warm, dry, indoor environment and left to passively cool for 2 hours before the commencement of observations. Though it is fully acknowledged that cooling fans can accelerate the acclimation process and help scrub away the boundary layer on the primary mirror, no such fans were used in keeping with the procedures of the aforementioned historical figures, none of whom had access to (or knowledge of) such fans.

Observer; suitably attired for cold weather observing; several layers of clothing; vest, jumper, overcoat, hand gloves, hat( me ole beanie). No dew shield used.

The following systems were examined in the 12″ f/5 Dob:

Theta Aurigae; a greatly unequal double, primary (A) , magnitude 2.6, secondary (B) magnitude 7.2. Separation 4″.

Iota Cassiopeiae: Triple system: AB- magnitudes 4.6 and 4.9 separated by 2.6″

AC: magnitudes 4.6 & 9, separation 7.1″

Eta Orionis: AB: magntidues 3.6 and 4.9; separation: 1.6″

Eta Geminorum (Propus): AB: magntidues 3.1 and 6, separation ~1.7″

52 Orionis: Classic Dawes pairing; AB equal 6th magnitude components, 1″ separation.

All systems observed either naturally or using a Baader single polarizing filter which cuts glare and increases contrast without imparting a colour shift to the stellar components.

Power employed: 277x throughout (Meade Series 5000 5.5mm UWA ocular).

Results:

The telescope resolved all 5 systems beautifully. The enormous resolving power and light gathering capability of the 30.5cm Newtonian made observing them especially thrilling. While there were many moments during the observations where the stellar images broke up or swelled slightly, there were also many opportunities where the images came together, producing text-book perfect results. As aperture increases, the size of the Airy disk shrinks, allowing the faint, close in companions to be more readily seen.

Iota Cassiopiae was quite simply stunning! All three stars appeared very bright and round as buttons in the 12 inch telescope at 277x. I have not personally experienced a better view of this triple system. Unequal pairs were always more challenging owing to the glare of the primary components, but still readily observed.

Propus(Eta Geminorum); is a particularly difficult system to crack, but on this evening the faint close-in companion presented better than I have ever seen it in my 8″ f/6 Newtonian at any power; the sheer resolving superiority of the 12 inch instrument clearly strutting its stuff.

A polarizing filter screwed into the bottom of the 1.25″ ocular significantly improved the aesthetic of the images by reducing glare and increasing contrast (read darker sky hinterland) very reminscent of a large refractor. Indeed, the filter made it significantly easier to prize the faint companion of Propus and Theta Aurigae in the same instrument.

The closest pairing observed on this evening – 52 Orionis – produced an image that was in a completely different league to any of the smaller Newtonians I have enjoyed testing. The components were much brighter, easier to see with lots of dark space between the components.

All in all; a very good short session under the starry heaven!

Discussion:

The Newtonian reflector has clearly come along way since it was first conceived of by Isaac Newton in the late 1600s. And while speculum metal allowed great gains to be made in both amateur and professional astronomy circles, it may surprise some readers just how far the reflector has been intelligently re-designed ever since those glory days of the past. Did you know, for example, that according to the studies of Dr. Wolfgang Steinicke, an expert on the telescopes at Birr Castle, that the 72 inch Leviathan of Parsonstown had a light gathering power equivalent to a modern, state-of-the-art 25 inch Newtonian reflector [see my book Chronicling the Golden Age of Astronomy,  as well as chapter 7 of William Parsons, 3rd Earl of Rosse: Astronomy and the Castle in Nineteenth-Century Ireland (Charles Mullan ed. 2016)]. Seen in this light, this author considers himself very fortunate indeed to have acquired such a great telescope as the 12 inch f/5 Dob for just a few hundred pounds( it was second hand).

The reader should note that these results are not at all exceptional. Indeed, the author has clocked up many similar nights where the full power of the 12 inch can be pressed into service. Neither is the author out to set any records; the closest pair thus far resolved has only been ~ 0.7″ but the same instrument is fully capable of resolving significantly closer pairs should he wish to pursue them. These results are wholly consistent with the historical archives of many of the early observers mentioned in the introduction, who managed to split extraordinarily close pairs with telescopes of broadly equivalent aperture. For example, T.W. Webb was able to resolve the components of Eta Coronae Borealis using his silver-on-glass 9.5 inch f/8 With-Berthon Newtonian, which had a separation of 0.55″ in the 1870s. Such results make it patently clear that such work can be acheived with larger Newtonians, with excellent results.

Focusing is very challenging in such a fast telescope as the f/5 Reveation Dob. The author very much appreciates the fine focus on the dual-speed Crayford that came with the ‘scope. At f/5 it is a very worthwhile tool in attaining the most precise focus possible.

Filters, such as the Baader single polarizer, are very useful in attaining the right balance between image brightness and contrast. The advantage of using the latter filter is that it does not impart a colour shift to the stellar images, allowing the observer to record the pure colours of the component stars. Using a blue filter will also help resolve the very tightest pairs, as the resolving power of the telescope scales inversely as the wavelength of light used to probe the system. When you have access to such a large telescope, it collects so much light that productive work with even deeply coloured(read low transmittance) filters becomes very worthwhile.

As always, the author would encourage others who have access to such a large Dobsonian to give such systems a try. When careful attention is givien to both collimation and acclimation, the sky’s really the limit!

Thanks for reading and keep looking up!

 

If you liked this blog and wish to support the author, please consider buying a copy of his new book: Chronicling the Golden Age of Astronomy, newly published by Springer-Nature(available in both hardback or electronic formats).

 

De Fideli.

 

 

The Lockyer Sequence

New year’s Day 2019: Plotina starting well on a trail first blazed by Sir Norman Lockyer(1836-1920).

On the evening of January 1 2019, I set up my 130mm f/5 Newtonian astride its Vixen Porta II mount. Conditions were cold, still, and frosty, with temperatures between 0 C and -2C. Seeing was judged to be very good (Antoniadi II).

My purpose this evening was to examine a half dozen double and multiple stars in Orion, as suggested by the distinguished Romanian observer, Mircea Pteancu, who kindly alerted me to a reference made by Norman Lockyer et al in their book, Stargazing: past and present (1878). On page 164 of that book, the authors describe a sequence of double and muliple stars in Orion, which present systems of varying degrees of difficulty for the curious telescopist. After careful collimation and adequate acclimation, the 5.1″ reflector was turned toward the Celestial Hunter, beginning at about 22:00UT and the following systems examined at magnifications ranging from 118x to 566x. The results are shown below:

The Lockyer Sequence.

 

Notes:

The times and magnifications employed are displayed beside the drawings, which depict their orientation in the Newtonian reflector. For all sketches, south is up and west is to the left.

Teasing the close companion to Zeta Orionis apart from its brilliant primary did prove quite tricky, but with a concentrated gaze during the stiller moments, it did yield to the 130mm telescope. The reader will also note the much fainter(10th magnitude) shown at the lower right of the sketch.

The most challenging proved to be 52 Orionis(1″ separation), but with its decent altitude at 22: 43UT, I was able to resolve this classic Dawes pair ( twin 6th magnitude components)  using very high powers. Intriguingly, I first attempted this system by coupling a Meade 3x Barlow lens to a 4.8mm T1 Nagler yielding 405 diameters but without much success. The image was quite dim and very difficult to see the components distinctly. As an experiment, I switched to a Meade Series 5000 5.5mm ultra-wide angle ocular, coupling it to the same 3x Barlow but I also screwed in a 1.6x Astroengineering 1.6x amplifier yielding a power of 566x. To my great surprise, I found the image of the system to be significantly brighter than with the old Nagler and it was much easier to prize the components apart. I can only suggest that the better (read more modern) coatings on the Meade 5.5mm ultra-wide angle allowed greater light throughput, despite the higher powers employed.

566x represents a power of 111x per inch of aperture.

The 130mm f/5 Newtonian continues to surprise and delight me. It’s small, high-quality optics, thermally stable (cork-lined) closed-tube design, and ease of attaining perfect collimation all contribute to its efficacy as a medium-aperture double star instrument.

I would encourage others who have similar equipment to give these beautiful systems a visit. What better way to entertain and challenge a dedicated observer on a cold winter’s evening!

 

 

De Fideli.

A Winter Adventure with a 130mm f/5 Newtonian.

Plotina; the author’s 130mm f/5 Newtonian doing its stuff under a Christmas sky.

Sunday, December 23 2018

With the Christmas holidays now upon us, we were lucky enough to enjoy a beautiful  winter day, with clear blue skies illumined by a feeble Sun. This time of year, darkness falls very early, well before supper time, and as luck would have it, the sky remained clear after dark. I decided to field my trusty 130mm f/5 reflector, mounting the telescope on an old Vixen Porta II mount at about 4.00pm local time, and let it cool down to ambient temperatures, which had already reached 0 C by sunset. Accompanying the telescope was a 8 x 42 roof prism binocular, used for finding fainter objects more quickly than with the telescope and its finder alone.

The cold weather was never a concern though; afterall, the telescope has strutted its stuff many times in sub-zero temperatures, as I’ve described in many previous blogs. At 4.45pm I began my observations with a look at the Red Planet, Mars, which by now had greatly receded from the Earth, but at least had now reached a very decent altitude in the south. Inserting a Parks Gold 7.5mm eyepiece coupled to a Meade 3x achromatic Barlow lens yielding a power of 260 diameters, I was greeted by a tiny little salmon-pink orb, quite obviously gibbous in cast, with a few dark markings visible across its surface. The view was good and steady and very satisfying given the great distance to which it had receded to since its glory days during the summer, when the planet swelled to an enormous size as seen through the same telescope.

But what I was really after this evening was a suite of double stars, my staple observational targets for many years now. Having abandoned small refractors and Maksutovs for the greater efficacy of the 5.1 inch Newtonian reflector, I turned the instrument on Epsilon 1 & 2 Lyrae, a summer favourite, but still suitably placed for observation in the early evenings of December. Keeping the same eyepiece and Barlow in the focuser, I obtained a wonderful, text-book perfect split of all four components. And though I had seen such an apparition more times than I care to remember, it still brought a broad smile to my face to see these old friends in a Christmas sky.

From there, I moved over to Delta Cygni, a much better test of atmospheric turbulence than the four stars of Epsilon Lyrae. Carfeully centring and focusing the bright white luminary, I obtained an excellent and stable image of the faint, close-in companion at 260x. It was at that point I knew that conditions were good enough to attempt the trickier targets that were lining up in the sky.

Moving the telescope further west, I could see bright Altair, so I tried my hands at the difficult and faint Pi Aquliae nearby, which I first reconnoitred with the 8 x42, before centring it in the 6 x 30 finder ‘scope of the main telescope. Keeping the power at 260x, I achieved a reasonable split of these fairly closely matched components but I could see that it was noticeably inferior to how it looked in the late summer and early autumn, when it was higher up in southern skies. Still, I was well chuffed to have bagged this system so late in the season.

Moving several degrees east into the diminutive but lovely constellation of Delphinus, I immediately aimed for the jewel of the celestial Dolphin; Gamma Delphini. The 5.1″ reflector made light work of this easy but fetching double star which was best seen at 118x using my Meade 5.5mm Ultra-wide angle eyepiece. From there, I sped over to Cygnus again and quickly located the multiple star, o^1 Cygni using the 8 x 42. Training the telescope on the system brought another huge smile to my face, as the beautiful and wide colour constrast triple system came to a perfect focus, their tiny Airy disks and faint first diffraction rings calmly presenting themselves in the frigid air.

After that, I panned the telescope eastward until I centred Almach (Gamma Andromedae) in the 118x eyepiece and was greeted with a beautiful split of this comely, colour-contrast double star. Even after all these years of observing it, it never ceases to inspire me! “That was easy,” I said to myself, ” but let’s have a go at a much more tricky system.” With that thought I trained my binocular at a patch of sky in eastern Cygnus, specificially looking for a faint pair of stars, the brighter of which was Mu Cygni. Quickly aligning the telescope on the same patch of sky, I inserted the 260x eyepiece-Barlow combination described earlier and carefully focused. Voila! There it was; a wonderful text-book perfect split of this very close binary system, with the wider, fainter star visible in the same field comprising the triple.

Finally, I visited the endlessly lovely Albireo, now fairly low in the western sky. Needless to say, it was a sight for sore eyes. It’s true; some of the most beautiful objects in the night sky are the easiest to access!

So far, so good. I took a break for a few hours, enjoying a good, traditional Christmas roast with my family, keeping the telescope in an unheated outhouse all the while, so as to allow me to quickly engage with the night sky. Beginning again around 10:15pm, with the bright Moon having risen in the sky and the temperatures having dropped to -2C, I  started in Orion, which at the time of observation, had still not culiminated in the south. Hoping for a continuation of the steady skies experienced earlier in the evening, I trained the 130mm Newtonian on mighty Rigel. Slightly anxious, I carefully focused the bright white luminary in the 118x eyepiece and was relieved to see that the primary Airy disc was small, round and virtually free of turbulence. And there beside it was the tiny spark from its feeble, close-in companion. It was a beguiling sight!

From there I moved a wee bit to the northeast and centred Eta Orionis.This is a more difficult pair to resolve and so requires higher powers to tease apart. But at 260x it was easy; the two stars, plain white to my eye, appeared roughly east to west in orientation.

By now, mighty Auriga, the Charioteer, had risen to a great altitude, high in the east, and so I turned the telescope on its most prestigious double star; Theta Aurigae. The telescope made light work of this tricky system, the faint, steely grey companion being stably held in the frosty air.

A night of winter double star observing could never be complete without a quick look at Castor A & B in Gemini. Just east of the bright, near-full Moon, I had to battle with the glare a bit before centring the system in my 6 x 30 finder ‘scope. But at 260x, the twin white stars, pure as the driven snow, was a msemerizing sight in the telescope; the Airy disks small and round as buttons, each surrounded by a single, faint diffraction ring.

Finally, I thought I would try my hand at 36 Andromedae, which was first found with a bit of ferreting around using the 8 x 42 binocular. And sure enough, I was able to split this 1 arc second, near equally bright pair in the telescope without much effort at 260x. However, it was better seen using the higher power of a 4.8mm T1 Nagler eyepiece coupled to the same 3x Barlow yielding 408x. I was mightily impressed with just how good and stable the image remained as it shot across the field of view at this ultra-high power.

Vigil ended shortly before 11pm local time.

What a great night!

Simple pleasures with a simple telescope!

The stuff dreams are made of.

 

De Fideli.

The Year in Review

Plotina: the author’s 130mm f/5 travelling Newtonian sampling the beautiful autumnal skies of Dumfries & Galloway, southwest Scotland.

Anno Domini MMXVIII

We’ve reached the end of yet another year; and boy do they come round fast and furious! It seems like yesterday when the freezing Beast from the East was upon us, and that gave way to a unusually warm summer. Our family ventured across the waters to visit my brethern remaining in the south of Ireland and to catch up with old friends and acquaintances. But it was also a year where I made considerable progress establishing how good the British Isles are for doing all kinds of astronomy, having completed a survey of a dozen or so different sites across the British Isles. Despite the prognostications of casual observers, Britain and Ireland possess many prime locations to conduct visual astronomy, and in particular, high-resolution double star astronomy using small and medium-sized Newtonian reflectors.

In August, I conducted a month-long observational program to establish to what extent the Jet Stream affected my ability to resolve a variety of double stars ranging from between 1 and 2″ angular separation, finding no real evidence in support of its alleged effects and that it need not deter a determined observer to enjoy visual astronomy. It was, to my knowledge, the first such survey to be conducted on the subject.

My scepticism concerning the virtues of small, expensive refractors grew ever stronger throughout 2018, when I finally rid myself of the last remaining apochromatic refractor in my stable. As I have exhaustively shown, a much simpler and less expensive 130mm f/5 Newtonian proved superior to a 90mm ED glass on all sky targets. The former instrument has become my grab ‘n’ go telescope of choice, based solely on optical performance.

I will not be updating my book on refractors, as my conscience will not countenance the continued cultivation of untruths about their supposed virtues in the field.

I’m a Newtonian convert!

In another project, I tested a variety of optical devices that enable observers to use Newtonian reflectors during daylight hours, finding that the 130mm f/5 Newtonian coupled to a Vixen erect image adapter to be a fine, cost-effective alternative to large, expensive ED spotting ‘scopes.

Schmokin; the Vixen terrestrial image adapter.

My continuing blog entitled: the War on Truth: the Triumph of Newtoniasm, I have collated the opinions of a large volume of observers and authorities in the field from around the world, both historical and contemporary, which clearly show that Newtonian reflectors in the 8- to 12-inch aperture class will outperform smaller refractors at a fraction of the price, in sharp contradistinction to two decades of nefarious promotion by so-called ‘experienced’ amateurs. One of the key reasons for this blurring of the truth pertains to my suspicion that many refractor enthusiasts either don’t know, or are unwilling, to accurately collimate these instruments and/or are too lazy to allow adequate thermal acclimation of the same.

That being said, I have been very encouraged by the response of the amateur community to this legitimate protest. It seems many more former refractor onlyists are willing to consider the Newtonian once more and that’s a good thing!

2018 has also been a year where I have re-discovered the considerable virtues of binoculars. As a series of recent blogs showed, I have found a range of optically excellent roof prism binoculars that suit the budgets of many more amateurs, enabling the hobby to grow and not stagnate. Although I have certainly not spent a small fortune buying every other model, as others have done, I quickly gravitated towards two instruments, both made by Barr & Stroud, a 10 x 50 unit for dedicated binocular astronomy using a monopod, and a most excellent 8 x 42 Savannah wide-angle instrument for casual stargazing and nature observation. The latter has become a constant companion on my long country walks. I sincerely wish that others will test these binoculars themselves and spread the love.

An amazing, general purpose binocular; the Barr & Stroud  Savannah 8 x 42 wide angle.

I intend to drastically cull my current crop of astronomy equipment in 2019 as it has weighed heavy on my mind of late. I have retired mighty Octavius, my 8 inch f/6 Newtonian reflector, as it has achieved everything I intended for it and much more besides. My intention is to eventually gift it to some keen amateur who will use it productively. My 5 inch f/12 refractor is similarly retired. The little Orion SpaceProbe 3 alt-azimuth reflector and my old 7 x 50s were bequeathed to Gavin, a very enthusiastic young man of 8, who showed unusual interest in astronomy, and uses them regularly to stargaze from his home just outside our village.

I plan to use just three instruments in the coming year:

A 12″ f/5 Newtonian(Duodecim)

A 130mm F/5 Newtonian(Plotina)

Binoculars.

These three instruments will enable me to enagage with the full gamut of amateur astronomy. They are all I could possibly want!

Duodecim: a fine 12″ f/5 Newtonian reflector.

I would like to produce more blogs on binocular astronomy in the coming year, Lord willing, as well as produce new reports with both the 130mm f/5 and 12″ f/5 instruments.

2018 marked the end of a long slog to get my new book into shape; Chronicling the Golden Age of Astronomy. It’s been five years in the making, but it was an enjoyable and worthwhile project, bringing together the selected works of many amateur and professional astronomers across four centuries of time, who used their telescopes, both great and small, to create the wonderful hobby we enjoy today. What I learned from their diligent adventures under the stars is incalulable and I have tried hard to capture the essence of their life and researches in this large, historical work. It is my fondest hope that it will be well received by my peers. Please check out the reviews as they appear.

A work dedicated to the heroes & heroines of our hobby.

Finally, I am in the process of writing a new book dedicated to the ShortTube 80 achromatic telescope which ought to be available at the end of 2019. I have amassed a large body of notes from several years of using this quirky little telescope in the field, which I hope will be of interest to the many amateurs, young and old alike, who use or have used the instrument in the past.

So, there it is!

God bless you all!

Neil.

 

De Fideli.

A Visual Extravaganza Under Dark Scottish Skies.

Looking east: sunrise over Wigtownshire.

 

The heavens proclaim the glory of God.
The skies display his craftsmanship.

                                                                              Psalm 19:1

 

Contrary to what you may have heard in the past, the British Isles offer many outstanding places to observe the heavens. Sure, we don’t have vast deserts or majestic mountain ranges that ascend for miles into the sky, but we are truly blessed with many sparsely populated regions, where the activities of human civilisation are minimal. Having lived in Scotland for more than half of my life, I have been fortunate enough to discover many fine locations that offer both very dark skies and good seeing conditions. One such region lies in Wigtownshire, in the extreme southwest of Scotland, in the district known as Dumfries & Galloway.

Not far as the crow flies from the Scottish Dark Sky Observatory, situated to the north of the Galloway Forest Park, the site offers nearly unobstructed views of the heavens from zenith to horizon in all cardinal directions. The gardens are decorated with beautiful beech and cherry trees, the leaves of which vibrantly radiate the rich colours of autumn during sunny spells. By day, there are many places to visit nearby, including the little town itself, famous for having more bookshops than any other in Scotland, as well as rugged country walkways and picturesque seaside villages that adorn the coastline all around the peninsula.

The nearby fishing village of Portpatrick on the west coast of the Rhins of Galloway.

 

During the four nights we spent there in mid-October 2018, we were fortunate enough to encounter long clear spells every night, and with a low-lying harvest Moon setting early, the skies became wonderfully dark, allowing the full glory of the northern heavens to manifest itself. Owing to its location near the sea, the skies here are regularly swept clear of particulates, which makes for exceptionally transparent conditions, ideal for astronomy.

The shores of Loch Ken, near Castle Douglas.

I took along my best travel ‘scope; a modified 130mm f/5 Newtonian, which has proven superior to a string of other, more traditional, travel ‘scopes I have enjoyed in the past, including a TeleVue 76 & 102, a classic TeleVue Genesis Fluorite F/5,  a PrimaLuceLab ED 90 and a variety of smaller Maksutovs in the 90 to 102mm aperture class. With very generous light grasp and resolution, the 5.1” Newtonian has proven to be an enormously versatile instrument for exploring the landscape by day and by night. I also brought along my recently acquired Barr & Stroud 8 x 42 roof prism binocular to soak up ultra-wide field vistas of the northern heavens that perfectly complement the more restricted field offered up by the telescope.

Plotina: the 130mm f/5 Newtonian travel ‘scope used to explore the northern heavens.

 

To get an idea of how good the skies are here, 8 members of the Pleaides are clearly visible to my average eyes once it rises to a decent altitude, as is the North American Nebula in Cygnus. In addition, a string of Messier objects in Auriga, Perseus, Cassiopeia and Pegasus are much more easily discerned visually than at home. The glory of the Milky Way, snaking its way roughly from east to west, is intensely bright here, so much so that at times I considered it a form of light pollution lol.

The patch of land where most of the observations were conducted, looking northeastward.

 

Clear skies come and go here all the time. For a few hours, they remain resolutely clear, then the clouds roll in off the Irish Sea, occluding the celestial realm for a spell before being swept away to the east. Although many calm spells occur at this site, watching the direction of smoke billowing upwards from the chimney of the cottage’s wood-burning stove, indicates that the prevailing winds are gentle and southwesterly in direction. In addition, the site is very quiet and peaceful, naturally arousing deep spritual feelings from within. In the wee small hours, only the sound of gentle breezes whistling through the trees breaks the silence.

The first night proved profitable for outreach. Although this was our third trip to the cottage, a change of ownership occurred earlier in the Summer, when a married couple with a young family underwent a home-coming of sorts, returning to the land of their youth. Their two boys instantly struck up a friendship with our lads, and so the evening started by showing them the rugged beauty of the Moon, now at first quarter phase, through the little telescope. Nearby Mars proved a little underwhelming though, as by this time it had receded greatly from the Earth in comparison to how it looked in August last, but they were still thrilled to see its little pink disk broiling in the low altitude air close to the southern horizon.

After enjoying some supper, I ventured out later in the evening when the Moon had set to show our guests, which now included the boys’ father, some of the showpieces of the deep sky with the 8 x 42 binocular and the telescope. The Andromeda Galaxy and its spooky satellite systems – M32 and M101 – made a big impression on them. For these objects I used the 25mm Celestron X-Cel LX eyepiece delivering a clean 2.3 degree true field at 26x. The dad was deeply moved with the Perseus Double Cluster, as were his sons, but I also gave them an opportunity to see M57 in Lyra and the beautiful colour-contrast double star, Albireo, well positioned high in the northwest sky in Cygnus. The owner was very surprised to learn that the telescope I had brought was quite inexpensive and seemed genuinely interested in acquiring one for himself.

The telescopic views were complemented by carefree scanning of the heavens with the 8 x 42 binocular. Showing them where to point the instrument, they gasped with sheer delight as they beheld the riot of stars centred on Alpha Persei, now high in the southeast, as well the way the binocular broke up the frothy Milky Way into myriad pinpoint stars against a coal-black sky. I don’t think the father had realised just how good the skies over his farmstead could be. I made it clear to him that he was very fortunate indeed to have such outstanding natural beauty on his doorstep!

The second day of our trip (October 16) started cloudy with some light drizzle, but as the day progressed the rain ceased and the clouds began to break up to leave a fine evening. I waited until the Moon was out of the sky before setting up the 130mm f/5 to observe M 15 in Pegasus. Having the 8 x 42 binocular hanging around my neck at all times, I was able to quickly zoom in on this fairly bright Messier object, first with the binocular, which presented the structure as a reasonably bright fuzzy star. By using averted vision, the size of M15 nearly doubled in size to more than half the size of the full Moon. Using averted vision with binoculars is a new activity for me but it certainly pays dividends! The great darkness and transparency of the air at our observing site enabled the decent light grasp of the telescope to be used productively and I was able to resolve a few dozen of its outlying stars using a 4.8mm T1 Nagler yielding 135x; a very tiny eyepiece by modern standards but a true marvel of optical engineering. Much more compact than M 13, the core of M 15 remained very bright and highly condensed, but as it floated through the huge field of view of the eyepiece with its fairly tight eye relief, I brought to mind its prodigious distance; 34,000 light years, far out in the halo of our galaxy.

From there I sped eastwards into Perseus to see how an improved sky would present the large open cluster M 34. Again, the binocular was used to locate the cluster first before centring it in the field low power (26x) field of view of the telescope. Even at 26x, the view was very impressive, with a sprinkling of 60 or so stars haphazardly strewn across a field of view roughly the same as the full Moon. The view was immeasurably improved using my trusty Parks Gold 7.5mm eyepiece (87x) which framed the entire cluster with just a little room to spare.

At 22:36UT I recorded an extraordinarily bright fireball, which was extremely long-lived, darting across the sky from north to south. At its brightest it was maybe twice the size of the full Moon and took approximately 4 seconds to fizzle out.

The 8 x 42s also made light work of tracking down the rather elusive face-on spiral galaxy, M 33 in Triangulum. At 26x in the 5.1″ the galaxy took on a ghostly cast in an interesting field of mostly 8th and 9th magnitude stars. To my eye, it looked for all the world like a planetary nebula more than a galaxy, with a slight greenish hue. Still, the extra darkness and improved transparency of the Wigtwonshire sky certainly added to the enjoyment of the view. I was particularly delighted by how well the little roof prism binocular could pick it up, as this object has a notoriously large size and low surface brightness.

With the time rapidly approaching local midnight, it was time to have a closer look at the magnificent Pleiades asterism in Taurus. For this target, the binocular proved the superior instrument, with its low power and generously wide field of view (7.33 angular degrees). Riding high in the eastern sky, it was quite simply stunning! Much of the cluster appeared to be enveiled in a fog-like nebulosity which gave it a rather life-like translucent appearance to my eye. No words come close to describiing the full glory of this extraordinary natural beauty and I spent several silent minutes just enjoying the spectacle.

I ended the vigil that evening by examining just a few double stars in the telescope. My notes from earlier years showed how good the site is for conducting high-resolution double star observing during the Summer months, but I wasn’t out to break any records. Suffice it to say that systems that have traditionally been described as ‘difficult’ in more conventional grab ‘n’ go telescopes are beautiful and easily rendered in this instrument. For example, I achieved a most excellent split of the triple system, Iota Cassiopeiae, now very high overhead, using my favourite tools in this telescope for carrying out such work; a 7.5mm Parks Gold coupled to a Meade 3x achromatic Barlow yielding 260x. The three stars were pinpoint sharp (a result of precise collimation using my Cheshire) and the subtle colour differences easily discerned to my eye. Almach (Gamma Andromedae) was gorgeous too at the same power, as was Polaris A & B and  Delta Cygni A & B.

Simply superb for tight double stars; the author’s 7.5mm  Parks Gold eyepiece coupled to a 3x Meade achromatic Barlow lens.

 

Newtonian telescopes are excellent diviners of double stars, an attribute that still appears to be lost on many contemporary amateurs. I have cultivated a theory to explain this anomaly. I suspect that many refractor enthusiasts (onlyists?), accustomed to the hassle-free observing with small refractors, never properly learn how to collimate Newtonians(it does take a while to fully learn the skill!) and, as a result, they attribute their mediocre performance in this regard to other factors and not to badly aligned optics. It’s just a hunch, but I have good reasons to believe it!

With the Moon setting later in the evening of October 17, I gave the telescope a rest and just enjoyed the 8 x 42 binocular. Up until fairly recently, I had forgotten just how wonderful it is to use such a small and lightweight instrument on its own terms. My first target was the magnificent Double Cluster (Caldwell 14) now very high in the eastern sky, as well as the less well-known open clusters surrounding it including the fairly large Stock 2(~1 degree), found by following a curvy chain of stars northwards, away from the twin clusters, and the small and compact (~10’) NGC 957. The binocular view provides a unique perspective that just can’t be replicated in even the smallest rich field telescope.

From there I sought out Kemble’s Cascade, tucked away under Perseus in neighbouring Camelopardalis. A steady hand is a great virtue when deriving the most out of this remarkable linear arrangement of mostly 8th and 9th magnitude suns. Though the cluster is well seen from my home further north, the darker and more transparent skies here made it all the more thrilling to study. For me, binoculars are almost always about hand-held instruments, but I found it beneficial to steady the view on the wooden farm gate on the grounds, where I was able to distinctly make out the small foggy patch denoting the open cluster NGC 1502, where the cascade abruptly terminates.

A little achromatic pair.

 

Though not the best season to explore M 81 and M82 in Ursa Major (they are much higher in the sky in the Spring as seen from the UK), they were very easy to locate in the 8 x 42 binocular despite the constellation’s fairly low altitude in the northern sky at this time of year.  Considerably more challenging though was M51, the famous Whirlpool Galaxy, across the border in Canes Venatici, and even lower down in the sky, which presented in the binocular as a slightly elongated fuzzy patch.

Over in the west, about 8 degrees due south of golden Albireo and on the border with Sagitta, the Coathanger (Collinder 399) asterism was also a joy to observe with the 8 x 42, albeit ‘upside down’ in comparison with the low-power view in the 5.1” reflector. The sense of unity among the stars which comprise the asterism is a pleasant illusion however, as they are actually situated at varying distances from our Solar System. Also nearby, the binocular made light work of tracking down the large planetary nebula M27, which looked like a tiny, incandescent cloudlet against a sable background sky.

Later in the evening, the large and prominent constellation Auriga, represented by a great pentagon traced out on the sky, gained altitude in the east. At its heart, the 8 x 42 presented the three open clusters M 36, M 38 and NGC 1893 very well indeed as foggy patches in a beautiful, rich field glistening with myriad, faint Milky Way stars. M 37 was easy too, just east of the pentagon. About one third of the way in a line from M38 to brilliant yellow Capella, the binocular also swept up the small and faint open cluster, NGC 1857.

As local midnight approached, Taurus had risen to a decent height and it was the ideal time to examine it with the binocular. The generous 7.33-degree field of the 8 x 42 presented the Hyades asterism in all its wondrous detail. Brilliant orange Aldebaran(not a true member however) proved to be a mesmerizing sight, as did the many binocular doubles the instrument picked up immediately to its west. Again, telescopes can’t really do justice to this asterism, as its full glory is hopelessly lost in their much smaller field of view.

As a test, I tried my hand at locating the rather elusive M1 (Crab Nebula) centred on a spot roughly 1 degree to the northwest of the bright blue-white star, Zeta Tauri. I was unable to see anything of this Messier object just hand-holding the binocular, but I believe I achieved success by steadying the view a little on the wooden fence post. Considering that M 1 is a rather lacklustre telescopic object in small and medium aperture ‘scopes, just glimpsing the tiny, roughly 6’ x 4’ smudge was considered a notable visual achievement by this author!

I ended the binocular vigil by welcoming Gemini over the eastern horizon. Though not quite visible to the naked eye owing to its very low altitude at the time of observation, my tiny 42mm ‘double achromat’ made light work of picking up the lovely telescopic open cluster, M35, at the northwestern-most foot of the constellation, together with the fainter open cluster NGC 2158 just next door. This ‘double cluster’ of sorts will look far more impressive when the constellation gains altitude in the coming months.

By half past midnight local time, and with more of the lights from the small, sleepy town nearby having been extinguished, the sky became maximally dark. “The constellations look just like they do in my observing guide!“ I wrote in my logbook.  At the zenith stood majestic Cassiopeia, and ahead of it, Cygnus, now sinking low into the west. Behind it, as if in some kind of grand procession, came Perseus, Auriga, Taurus and mighty Orion looming large in the southeast. The view was so awe-inspiring that I set my binocular aside and just sat in silent contemplation of the lightshow presented to my weary eyes. This, I thought to myself, is the view of the heavens that was accessible to the vast majority of people who ever lived. It had a singular beauty all of its own; just the way the Creator intended it!

And that’s where it all ended on the penultimate night of our stay.

After spending our last day out at Portpatrick(October 18) and a nice family dinner at Bladnoch, we returned to the cottage after dark and to rather more overcast skies. I did venture out to have a look at the waxing gibbous Moon which culminated in the south about 20:00UT when the clouds began to break up once again. Though not a dedicated lunar observer by any measure,  the telescope delivered lovely high contrast images at low and medium powers (up to about 135x). The Moon would not be setting until much later this evening however, so I set the telescope up for work that would not in the least be affected by the encroach of lunar light; double stars.

Plotina; ready for a night of casual double star observing.

 

For this work, I charged the instrument with my Parks Gold 7.5mm eyepiece coupled to a good 3x achromatic Barlow lens yielding 260x and off I went to assess how well the telescope would do this evening. After obtaining lovely splits of Delta Cygni, Iota Cassiopeiae and Epsilon 1& 2 Lyrae, I knew conditions were very good indeed; as they are in many other places in the British Isles. The 1.5″ pair, Pi Aquilae, was a little bit more suspect though, owing to its much decreased altitude in the western sky at this time of year.

A little later, I enjoyed text-book perfect images of Gamma Andromedae, its beautiful colour contrast never faiing to bring a smile to my face. The stellar images in this telescope hardly ever fail to impress. It’s a combination of perfect collimation, modest aperture, good thermal management, adequate light baffling and high-quality optics, but it also requires clear and steady skies, which are accessible to far more observers than has been reported in the recent forum literature.

Two systems in Perseus also proved profitable; Epsilon Persei, with its very faint close-in companion which, of itself, acted as an excellent test of telescopic contrast, and Eta Persei, a lovely wide open, colour contrast double, with a magnitide +3.5 orange supergiant primary and turquoise secondary shining much more feebly at magnitude +8.5.

Finally, this was the evening that I also obtained my first clean split of the tricky system, Theta Aurigae, which was perfectly resolved in the 5.1″ reflector at 260x; my first such splitting of the new season! The difficulty with such a system is the great brightness differential between the components (+2.6/ +7.5) and close angular separation, but the 5.1″ f/5 Newtonian managed it perfectly well as it has done in previous seasons.

I made a quick sketch of how it appeared in the telescope at 22:25 UT (shown below).

An old friend: Theta Aurigae.

 

Note added in proof: On the frigid evening of October 29 at 22:15 UT, in an ambient temperature of -2C, this author took advantage of excellent seeing (Ant I) to obtain his second perfect split of Theta Aurigae of the season using the 130mm f/5 reflector at 260x from his home in rural central Scotland. The Airy disks were round as buttons with a single faint Fraunhofer diffraction ring. Almach (Gamma Andromedae) was spell-bindingly beautiful and calm in the same telescope when examined just a few minutes later.

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Concluding Comments:

The intensely curious & friendly little hens on the farmstead that cannot help but entertain the visitors!

 

It was good to get away.

The weather was settled and mild throughout, with only the occasional spot of rain. All four nights proved to be good and clear for long spells and the days were filled with worthwhile family activities out and about. This is a great place to observe the preternatural beauty of the night sky, tucked away as it is far from the cities and their horrendous light pollution.

We will certainly be visiting again!

We packed up the car early next morning with the intention of getting a good head start on the road back north. Inevitably on such trips, we always leave stuff behind. Sure enough, the owner emailed us later the same evening informing us that he had found a ” telescope cover” aka my flexi dew shield, and a set of earrings belonging to my wife. The boys were not immune to absent mindedness either, as a pair of ankle socks were found inside one of their beds. He kindly offered to post the items back in the week ahead. On Wednesday, October 24, a large yellow package arrived at our home with the said items inside. I emailed him back later the same evening, thanking him for his prompt attention to this matter but also with the offer to reimburse him fully for his efforts. He replied that there was no need:

“The astronomy lesson with the boys and myself was payment enough!”

Fair is fair I suppose lol!

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Appendix: Olber’s Paradox Redux: A Brief Mathematical Treatment of the Consequences of a Dark Sky at Night.

 

In 1823, the German physician and astronomer, Heinrich Wilhelm Olbers (1758-1840) considered an interesting question; why is the night sky dark? At the time, many scientists considered the Universe to be either infinitely old or large, or both. But Olbers considered the logical consequences of this pre-supposition. In an infinite Universe, Olbers reasoned, every line of sight should eventually meet up with the surface of a star. So, the night sky should actually look like the surface of a star. Indeed, the whole sky would appear the same; uniformly bright as a consequence of an infinitely large number of stars. This interesting conundrum is known as Olbers’ Paradox.

A system of stars (or galaxies) arranged in concentric shells with the Earth at the centre.

 

Words can only go so far though, so let us consider the problem from a simple, quantitative point of view.

Suppose we start dividing up the Universe into an infinite number of concentric shells, illustrated in the sketch I’ve made above(apologies for the crudeness of the sketch, as I’m no artist lol), centred on the Earth, with each shell having a uniform thickness, dr. Thus, the volume of each shell (dV) would be the surface area of a sphere of any considered radius r multiplied by its thickness(dr);

So dV = 4πr^2dr.

Now, if there are n stars per unit volume (denoted by asterisks in my sketch), then the total number of stars, N, in each shell will be:

N = 4nπr^2dr.

It is easy to see that the number of stars per shell will scale as r^2. However, the irradiance of each star will fall inversely as r^2, which has a cancelling effect on the overall brightness of each shell and so each shell ought to be uniformly bright.

We must slightly amend the above conclusion, as each star actually has a finite size, with the result that the nearer stars will eventually occlude the light from the more distant stellar members. Still, this would not happen until the entire sky looks as though it is covered with stars. And that returns us to the original conclusion.

Nota bene: The reader will note that each star in the diagram could be replaced by a galaxy with precisely the same consequences!

Let’s now look at possible ways to reconcile Olbers’ Paradox with what we actually witness when the Sun falls out of the sky.  For example, we might consider if the absorption of distant starlight by interstellar (or intergalactic) dust might provide a means of escaping the paradox. Unfortunately, if the Universe is infinitely old, or even existing for just a very long time (say for argument several orders of magnitude older than 13.87 Gyr), then we would expect that such dust particles would have absorbed enough radiant energy to raise their temperature to the same temperature as the surface of a star. And even if it became hotter than the surface of a star, it would merely radiate the excess energy, which the stars would absorb. The consequences are the same though; the sky would look uniformly bright in all directions.

Now consider an expanding Universe, where light is redshifted. In such a case, the energy of each photon of light would decrease as a function of radius, r, so this would help attenuate the brightness of each shell considered above. What happens when we add up individual contributions from each shell? At any fixed radius, the brightness would scale as ∫dr/r, which computes as the natural logarithm of r, i.e. ln(r). But one can readily see that if we choose an arbitrarily large radius, even the quantity ln(r) can become very large indeed, so not ultimately helping us to resolve the problem.

One way out is to consider a Universe that is not infinite in extent, so we can cut off our integral at that finite radius. But there is one other way to achieve the same result, by considering a Universe that has a finite age. Let this age be denoted by t. In this scheme of events, we will only observe stars that are close enough for their light to have traversed the Universe at the speed of light, c. Thus, the radius of that Universe is simply ct. In either scheme; a finite age or finite size, there will exist a limit to the number of concentric shells that could contribute to the brightness of the sky and so the paradox can be resolved!

I find it amazing that from the simple observation that the sky is dark at night, we can arrive at a rather profound conclusion. That said, this analysis cannot, by itself, distinguish which of those scenarios, finite size or finite age (or even both), is the ultimate reason for the darkness of the night sky, but its consequences raise other philosophic/theological questions; if the Universe had a beginning, which has long remained the consensus amongst cosmologists, who or what brought it into existence?

You can’t have an uncaused cause!

To my mind, there is little doubt that the God of the Bible provides the best and most complete answer.

 

In the beginning God created the heavens and the earth.

Genesis 1:1

 

Thus says the Lord who stretches out the heavens, lays the foundation of the earth, and forms the spirit of man within him.

Zechariah 12:1

 

Neil English discusses the work of hundreds of astronomers from the annals of history in his new book, Chronicling the Golden Age of Astronomy.

 

De Fideli.

The Venerable ShortTube 80 Refractor.

The author’s versatile ShortTube 80mm f/5 achromatic telescope.

 

In my next literary project, I’ll be dedicating my time to discussing the venerable ShortTube 80 f/5 achromatic refractor; an affordable, ubiquitous telescope that enjoys a 30 year + pedigree.

 

Tune in soon to find out why such an instrument deserves a book-length treatment……….

 

De Fideli.