John Mellish and the craters of Mars
Rodger W. Gordon
Throughout the past decade or two I have seen a large increase in attacks either in print or via the Internet, by various amateur astronomers, on various past astronomers. Almost always their targets are deceased and therefore unable to respond. These self appointed experts (who won't be named here, but who will recognize themselves) are to be found on both sides of the Atlantic. Much of their barbs revolve around a theme of, "If I can't see it, neither can you," or, "he must have been mistaken." Sometimes the person on the receiving end is still alive but mostly their venom is directed at those who have passed on. When one examines the accusers they tend to cloak their missiles in "astro-gobbledegook" which might fool most beginners or intermediates, but seldom fools those more advanced. They usually lack a basic knowledge of image formation and how it applies to astro-optical imagery and physiological optics, as for example, variation of an individual's eyesight, or even the fact that variations occur on the moon and planets either through the interplay of light and shadow (moon) or actual physical changes on the surface or in the atmospheres of the planetary bodies themselves.
One of the things this writer learned early on is the remarkable variation of individual eyesight. The following instance is a case in point. Even at my present age (61) my opthamologist has told me, "Gordon, except for your loss of accommodation, you have the eyes of a jet pilot." Flattering, but my eyesight was not as good as my mother's, even in my teens. She had, until later in her life, 10/20 vision. She could read the smallest letters on the Snellen eye chart with ease. She seldom looked through a telescope though. My first telescope (age 11) was a 30 x 40mm erect image spotting 'scope. Through this she had seen the phases of Venus, Jupiter's moons, Saturn's ring (barely) and lunar craters. In 1956, at age 15, I was able to purchase a 2.4-inch refractor which came with 40x; 64x; 88x; and 132x oculars plus a prismatic star diagonal and an erecting prism, the latter for terrestrial use. One evening after sunset, but before darkness set in, I observed Jupiter at 40x. Three moons were on one side of the planet and one was invisible. My mother came outside to hang up the washing, and I asked her if she'd care to take a look. She looked through the 'scope and then looked up at Jupiter without optical aid and then looked at Jupiter again through the 'scope and said, "Why are the moons on this side in the 'scope but when I look up I see them on the other side?" It took me a few seconds to realize she could see three of Jupiter's moons without any optical aid! I told her that she wasn't supposed to be able to see them that way, but she could. So I explained to her that the star diagonal, whilst giving an erect image also reversed the view. The best I've been able to do with the naked eye, on the few occasions when Ganymede and Callisto were at greatest elongation, but close together, is to see them as a single point of light.
Some supposedly good observers out there should remember that some individuals have far better eyesight than others!!
In the March 2002 issue of Sky & Telescope, Sue French, a very practical double star observer, tells how she was able to see Sirius B in her 4.1-inch apochromatic refractor. This observation, while unusual, is not as rare as one might suppose. French states that Sirius B was 5".5 arc from A. S.W. Burnham saw Sirius B in his 6-inch Clark refractor at a separation of 4".5 arc. In 1954; '55 & '56, C.J. Smith saw Sirius B with a 6-inch f/17 Witherspoon refractor, sometimes with the objective stopped down to 4 1/2-inches. In the latter part of 1953, H.M. Jeffers at Lick Observatory measured Sirius B with the great 36-inch refractor, at 6".4 arc. At least five colleagues of his, all amateur astronomers, also saw Sirius B with his 6-inch f/17 OG.
Rigel's companion is considered a test for a 2-inch telescope (Norton's Star Atlas - 1957 edition) and I've seen it several times at 90x and once at 78x in a 2-inch refractor with a Zeiss 50/540 objective, yet some recent observers have had problems seeing it in a 4-inch or even larger aperture! It's separation has altered little in the past 45 years. One has to surmise that, assuming reasonably good seeing, differences in eyesight account for the failure to see it using apertures with which it should easily be resolved.
We know that perception of contrast can differ markedly between individuals. We also know that contrast differences can be seen that are as little or less than 5%. Yet a colleague who is an optical engineer by profession, who performs laboratory tests on the optics of diffraction limited government surveillance instruments, tells me none of his staff can detect contrast differences on the test charts they employ, below 10%.
These illustrations should serve as reminders just how widely individual eyesight can vary. The average observer is lucky to see seven stars in the Pleiades with the naked eye. In 1962, while aboard a US Navy boat in the Atlantic Ocean, I saw 13, possibly 14, once the skies had cleared after the passage of a hurricane. Allowance has to be made for somewhat exceptional atmospheric conditions.
Laboratory experiments have shown that lines on a high contrast sine target can be seen at 1/100th Dawes' limit. Under good atmospheric conditions the limit is usually 1/10 to 1/20th Dawes' limit. Low contrast targets reduce detection. This however is detection, not resolution.
Another example of detail visibility versus invisibility is the variation in contrast on the planet Mars. A major dust storm will blot out all, or almost all surface features. After the dust clears, contrast of the more prominent features appears greatly reduced. At those times when the atmosphere is most transparent surface features seem enhanced. Formations like crater rims can also appear enhanced when temporarily covered in either carbon dioxide or water frost. Another well known example are the variations in colour and detail within Jupiter's Great Red Spot.
Lunar variations are almost always caused by the changing illumination (except in the rare instances of a verifiable TLP). Examples of detail easily visible or invisible a few nights later are the tiny craterlets on the floors of Plato & Deslandres, the Treisnecker rhille system, and the saucer shaped depressions within Ptolemaeus. Many other examples could be cited. The earth - moon distance can vary from as little as 216,000 miles to as much as 253,000 miles, a not inconsiderable difference. Detail detectable at the limit at perigee may well become undetectable at apogee. When the observations of others are analyzed it is necessary to be aware of all the factors appertaining, and yet many are overlooked.
The case of Percival Lowell is a most interesting one. Lowell claimed to see a Martian canal network with his 24-inch Clark refractor and the photographs taken using this and similar aperture telescopes tended to support his view. But Eugene M. Antoniadi, using the great 33-inch refractor at Meudon, and Barnard and Mellish using the great 40-inch Yerkes refractor, all claimed to have resolved Lowell's canal network into discrete detail. It is noteworthy that Lowell's hypotheses of intelligent life on Mars were based upon incompletely resolved details, but which his telescope "seemed" to resolve. Lowell was wrong in his interpretation of those details, but he should not be vilified for his opinions.
The case of sub-divisions in Saturn's ring system is even more interesting. Throughout all of the C19th and most of the C20th, professional astronomers insisted there was only one or possibly two true divisions; Cassini's and Encke's, despite voluminous visual evidence that many other sub-divisions had been seen by amateurs. In 1954 G.P. Kuiper observed Saturn with the Hale 200-inch reflector at 1,100x and pronounced no real divisions existed except Cassini's! We now know that veiling glare due to Kuiper being able to employ only 5.5x per inch of aperture, reduced image contrast, and that so brilliant was the image due to the relatively low power (exit pupil 4.6mm), that it would have been impossible to detect anything other than the Cassini division in Saturn's ring in any case. By 1962, the Shane 120-inch reflector had been used to photograph Encke's division with hints of others in ring B. Ironically Richard A. Proctor had, as long ago as 1859, in his book "Saturn", postulated that the shading on the interior ansae of ring B could only be due to innumerable sub-divisions. Now of course we know there are literally hundreds if not thousands of sub-divisions, and the professionals have been left with egg on their faces. Such is the fate of dogmatic and preposterous pronouncements.
Even nowadays resolving power and its dependence on contrast levels is imperfectly understood. We can measure it on test charts for example, but how the eye-brain system interprets lunar and planetary detail is a complex and incompletely investigated field. There is a common misconception that Dawes' limit applies to extended objects. It does not. Dawes' limit is applicable only to brilliant points of light seen against a black background. Lunar, solar and planetary detail frequently entails the detection of dark spots seen against a light background. A single dark spot can be seen against a light background at less than half Dawes' limit (Sidgwick 1955 A.A.H.). Jovian satellite shadows are an example of seeing dark spots below Dawes' limit. There are reliable observations of these shadows with as small as 2-inches to 2.4-inches aperture. Dark 'shadows' seen inside lunar craters before the terminator has reached them can be seen well below the Rayleigh limit. Large professional telescopes seldom reach their diffraction limit due to atmospheric factors. When they do, seeing is described as "extraordinarily good" or "near perfect".
Some time ago there was a discussion on the 'astro-chat rooms' about naked eye visibility of lunar craters. One can argue about what exactly is meant by visibility. In Wilkins and Moore 'The Moon' - p310, 1955, it is stated, "So large is Clavius that when on the terminator, it appears as a great bay filled with black shadow which perceptibly blunts the south cusp to the naked eye." This statement is open to differing interpretations, but it does seem that in this instance a lunar crater can be seen without optical aid. A 2 1/2x to 3x opera glass will show several, especially around first and third quarter.
In June 1901, T.J.J. See using the 26-inch U.S. Naval Observatory refractor observed Mercury in daylight. Mercury was near half phase, and its angular diameter was only 6".6 arc. See made a drawing that no one can doubt depicts crater like details and which looks remarkably similar to far encounter images transmitted by Mariner 10. See has had a lot of abuse hurled at him, no doubt much of it well deserved because of his abrasive and egotistical personality. But his observation and drawing should not be dismissed. See does not show any lunar type maria, though he compared his view as similar to lunar views. See's drawing proves beyond any reasonable doubt that craters can be seen on Mercury. In so doing it lays the ground for a strong case for Mellish's claim to have detected craters on Mars when using the great 40-inch Yerkes refractor during November 1915. Mellish described them as "crater pits" leaving little doubt that he had an extraordinarily good view (he used 750x and 1,100x). Mellish's eyesight by all accounts was in the extraordinary category too (Eugene Cross 1970-71).
Other astronomers purported to have seen craters on Mars were E.E. Barnard and H.P. Wilkins, again using the Yerkes 40-inch OG. Barnard made his observation during 1892 & 1894, and Wilkins in 1954 whilst on a lecture tour. There is an intriguing drawing of Mars made by Eugene M. Antoniadi in 1926 which gives his idea of what Mars would look like from one of its moons. Antoniadi depicts several lunar-like craters that interestingly enough (given the positional accuracy involved) coincide with several craters discovered subsequently by the Mariner spacecraft.
Did Antoniadi guess there were craters on Mars? Or perhaps had he previously observed them but decided not to reveal he had done so for fear of ridicule? We know Barnard was reluctant to discuss his own observations of Aerian craters and we also know that Barnard and Antoniadi had professional contact. Did they perhaps discuss their unusual observations, and mutually agree to withold their findings? This is speculation of course, yet it gives cause for reflection.
That craters were known to exist on Mars is clearly shown in an article in the Philadelphia Inquirer, October 15th. 1933. George W. Ritchey, who made the glass primaries for the 60-inch and 100-inch reflectors on Mt. Wilson, was investigating the use of metal mirrors in his quest to produce a giant 300-inch reflector. If the experiment had worked, Ritchey, in collaboration with C.H. Lutz, planned to locate five such telescopes at different sites and 'interconnect' them. Speaking about Mars, Ritchey states, "With my mirrors, photographs will be made that will show craters 70 feet in diameter and any object on Mars two miles in diameter will be well defined." Preceding this paragraph it was stated, "The new peeping tube will be able to descry a pit 70 feet in diameter in the planet's crimson surface." Ritchey indeed had a metal mirror telescope constructed as a test, but metal mirrors did not pan out.
In 1957, Max B. Miller wrote about Mars. Miller was a member of A.L.P.O., American Rocket Society; British Interplanetary Society, and the Meteoritical Society. Miller's article refers briefly to Mellish's observations, describing the oases as, "merely volcanic crater pits on the planet's surface."
In the early 1990's two observers, one a staff member of Sky & Telescope, the other an astronomical historian, observed Mars with the 42-inch Cassegrain reflector at the Pic di Midi. The planet's aspect was roughly similar to that during Mellish's observations 75 years earlier. They used 800x and 1000x, similar magnifications to Mellish's. Mellish observed from sunup to about two hours after dawn, and stated that the contrast improved as the sky brightened. This is a well known effect. Observing Mars and Jupiter in the early dawn or dusk, and Venus during the day, greatly reduces glare. However the two observers in question reported that contrast greatly diminished and they were unable to duplicate Mellish's findings. The article was written in a manner which indicated their negative results cast serious doubt on Mellish's claim. However, neither observer, despite their alleged observational skills and knowledge of telescope optics, bothered to question why contrast deteriorated in a fashion distinctly at variance with what Mellish (and others) reported. I queried one of them within a few days and asked him if they had checked to see if the 42-inch Cassegrain was effectively baffled, so as to prevent sky flooding? Guess what? They hadn't!!
Now here we have a case whereby two supposedly skilled observers, ignorant of a Cassegrain's need to be baffled for daylight observing, and who made no allowance when judging image contrast. As it turned out, the 42-inch Cassegrain was (& is) not baffled for daytime use, rendering their experiment completely and utterly meaningless!
The final word on Mellish comes from someone who perhaps knew him better than any other; the late Walter Leight. Leight and Mellish corresponded via hundreds of letters for almost four decades. Early in his career Leight was the eager pupil and Mellish his mentor concerning telescope optics. Mellish told Leight of his Mars observations in a letter in the 1930's. Leight purchased optics from Mellish over a span of years including an 11-inch f/14.6 objective that he built into a folded refractor for his private observatory. Several years before his death, I showed Leight a couple of articles that attacked Mellish's claims, including one in the Journal of the British Astronomical Association. Leight was a Quaker and a deeply religious man. In the 42 years I knew him (we were both members of the Lehigh Valley Amateur Astronomy Society for 38 years), I never heard him utter any profanity. After reading the articles and rereading them he turned to me and said, "they are entitled to their opinion but I think they are full of horse feathers!" That is the closest I ever heard him come to uttering a profanity. Leight stated that Mellish was one of the most honest men he knew.
Leight was for a time a professional optician at the Frankford Arsenal during WWII, working firstly on flats and later on reticles, becoming supervisor of the reticle department. To appreciate Leight's skepticism with Mellish's detractors, it is necessary to learn something of his background. Leight was perhaps the most remarkable amateur astronomer this writer has ever known. He observed Mars through five oppositions, 1924; '39; '56; '71 & '88. He built 19 telescopes; 21 if one counts two that used professionally made optics. He amassed three huge scrapbooks filled with observations and astronomical material dating from 1924 until well into his 90's. In the late 1950's he built a 19-inch reflector weighing over 500 lbs. He also made 116 violins and was cited in the book, "Violin Makers of America." He extensively used the 18-inch Brashear refractor at the Flower and Cook Observatory in Upper Darby in the 1930's, and carried his own eyepieces to use with it, as the observatory had only two oculars giving 150x and 225x. He manufactured many of his own eyepieces including Huyghenians, Ramsdens, Kellners, Symmetricals, Coddingtons, Tolles, and Hastings triplets (a Monocentric type). During his stint at the Frankford Arsenal he taught reticle making to Eastman Kodak optical engineers and received an offer from Eastman Kodak to head up their reticle department, which he declined. He was an amateur movie maker who built his own sets including miniature ones; did cartoon animation good enough to be offered a job with the Walt Disney studios in California, which he also declined. He joined the Sandurs Corps. near Allentown around 1950 in their photo-engraving department, eventually becoming supervisor. He did amateur astrophotography extensively, wrote several articles on photography for various photography magazines. His detailed drawings of telescopes and mounts show clearly that he hit upon the idea of the Dobsonian mount long before John Dobson. He developed a working model disc camera decades before Eastman Kodak, but never bothered to patent it. He wrote several articles for the L.V.A.A.S. "Observer" and had a feature article on his 8-inch f/26 Cassegrain (now owned by the author) and other Cassegrains in Sky & Telescope Jan. 1946. He was modest and never sought publicity. Had he chosen to do so he would have outshone every other amateur of his era. He made a movie entitled, "a matter of gravity" that had the audience practically rolling in the aisles, helpless with laughter at the L.V.A.A.S. - A.L.P.O. 1976 Convention. His lunar and planetary drawings are models of exactness and beauty. He had a wry sense of humour, yet it was never directed at anyone other than on occasion himself.
He built a large private observatory which housed his 8-inch f/26 Cassegrain, 11-inch refractor and several smaller 'scopes. He used solar telescopes of his own design which had focal lengths of 90 feet and 180 feet, in his yard. From the 1930's, his favourite ocular was a modified Zeiss orthoscopic with a 64° apparent f.o.v. It gave 972x on the 18-inch Brashear and 762x on his 8-inch f/26 Cass. Using it on the Brashear he told me that, "We often saw things (like numerous sub-divisions in Saturn's rings) we weren't supposed to see and we didn't mention them."
Walter Haas, founder of the Association of Lunar and Planetary Observers, also used the 18-inch Brashear and stated on several occasions that it gave him the best views of Saturn as he'd had in any telescope.
Leight was a devoted husband and father, a family man in the true sense of the word. He was an ATM in the tradition of Albert Ingalls, Russell Porter, Henry Paul, and Ralph Dakin. He wrote one book (non-astronomical) about a kidnapped Egyptian princess which is uncannily similar. and by far predates Hollywood movies with a similar theme.
When I first met Leight at the L.V.A.A.S. in the late 1950's we hit it off immediately despite the difference in our ages. He was a quiet unassuming person who seldom spoke at club meetings but when he did everyone paid attention. He had the unique ability to look at an optical or mechanical problem and derive a solution to it within minutes, and usually made detailed drawings on the solutions before attempting to put them into practice. If anyone can speak with authority on John Mellish it would be Walter Leight.
The following is a transcript of a letter from Mellish to Leight dated the 18th. January 1935:
In 1965 Mellish received a telephone call from E. P. Marty Jr. at JPL, congratulating him on having his Mars crater observations confirmed. Marty was the designer of the camera optics on the Mariner IV 1965 Mars flyby mission. Mellish was contacted the following year by Daniel H. Harris, via JPL, to which he replied on 25th. November 1966:
"Carpenter" is Claude Carpenter, who was a well known amateur and a long time member of the A.A.V.S.O. Mellish made his largest mirror for Carpenter - a 36". "Cave" is of course Tom Cave. Note too that Mellish was not quite certain of the Nov. 13th. 1915 date. That date has been used by the author, and others, when discussing the subject. In addition note that Mellish stated in 1966 that Barnard did not see the craters as craters like Mellish did. This does confirm Sheehan's discovery of Barnard's drawings and clearly indicates Mellish has the better view.
But other evidence points to Mellish's correctness in his Mars crater observations. Others, besides myself have investigated Mellish. One spent time interviewing Mellish's surviving children. That Mellish saw Mars in an extraordinary light is exemplified by the following: his children stated that their father didn't talk much about "shop" at mealtimes, but told his story of seeing craters on Mars to them so often they got tired of hearing it. They also said that they felt their father, "worked too cheap." In fact Otto Struve used Mellish to build astro-optics because, "he worked cheaper than anyone else." You could buy a Mellish refractor at half to a third the price of a comparable aperture Clark or Mogey, similarly equipped. A 5-inch f/15 refractor out of Mellish's shop during the 1930's was $275; far less than a 5-inch Clark or Mogey.
Mellish lost his Mars drawings in 1964 after a fire that destroyed his optical business. Tom Cave as a teenager saw those drawings during a visit to Mellish's shop around 1937. Cave produced a sketch from memory of them with the caution he had seen the originals only briefly. Interestingly Mellish's drawings were sectional, despite the disc being a mere 7".7 arc. Now sectional drawings of Jupiter are not uncommon, but they are of Mars, even at perihelic oppositions. But I know of no other sectional drawings of Mars when the disc was this small and when Mars was gibbous (approx. 89%). The mere fact that he made use of a sectional drawing surely testifies to the extraordinary amount of detail he must have seen? Tom Cave, who has probably observed Mars more often than anyone else during the C20th does not take a stance for or against Mellish's claims. But in several letters to me, Cave stated, "Stick to your guns, Rodger, on John Mellish and don't let them grind you down."
One of Mellish's detractors, though not doing an about face, has conceded Mellish may well have seen the rims of craters enhanced by CO2 or H2O hoar frost. The view might be similar to the bright rims of lunar craters within the lunar terminator. Mellish's view may have been imperfectly resolved yet sufficient to grasp their true nature. Even Percival Lowell may have seen the summit caldera of Ascraeus Lacus (now known as Ascraeus Mons) for his description tallies with the view of Mars at 450,000km by a Viking spacecraft. Lowell of course failed to recognize its true nature.
In 1944 Ronald Lee Cyn correctly assumed that many of the oases on Mars were actually craters. He then checked Mars drawings that showed dark spots and stated they were craters, even producing maps ("Life on Mars" - 1944). A later book, "Mars Revisited" reiterated his opinions in even greater detail, going so far as to compare crater sizes on Mars and the moon.
The late Frank Goodwin was a professional astronomer for a time and a long time member of the Chicago Astronomical Society. Later, a professional advertising agent for the medical and cosmetics industry. He is best known for the "Goodwin Barlow lens" of the 1950's & '60's. He was instrumental in getting US amateurs to adopt the use of the Barlow lens at a time they were almost unknown in the States. Goodwin referred to Mellish as , "One of the big four in amateur optics," the others being Ingalls, Porter and John Pierce. Mellish bought barlows from Goodwin and stated in a letter to Goodwin he did so because "Yours are better than mine." Rather unusual for a manufacturer complementing a rival on the quality of his product and an indication of Mellish's honesty. Goodwin was obviously aware of Mellish's Mars crater observations and in a rather extravagant advertisement in Sky & Telescope Aug. 1952, alluded that you might not see the craters on Mars without using a Goodwin barlow!
The following was written in 1952 by Frank Goodwin, to quote: "In view of the fovourable coming oppositions of Mars in 1954 and 1956, mirror and objective makers have been somewhat swamped with orders from advanced observers and professional astronomers for long focal lengths with which to see the finest details clearly such as the canals, large craters and mountain ranges on Mars. Hence mirrors are now being figured to f/20 and objectives to f/25.
At the age of 67 Goodwin wrote that he was formerly a professor of astronomy at a large university, a frequent guest observer at Yerkes, courtesy of E.E. Barnhard.
On Mellish, Goodwin wrote: "..one of the last of the famopus galaxy of telescope makers which include Clark, Brashear, Fechner, Lundin, McDowell. Close friend of the late Russell Porter, a close friend of Professor Hubble, now at Mt. Palomar. I met him at Yerkes many years ago when he was there along with Professor Barnhard.
That Mellish's optical skills were excellent is shown by the following comments: Tom Cave's 2 1/2-inch Mogey refractor was loaned to a relative. When it was returned one of the elements was broken. Cave took it to Mellish and Mellish made a new element for it and said it performed better than the original. Anyone who can improve a Mogey is a craftsman to be reckoned with. Cave stated to me that Mellish made excellent optics under primitive working conditions, using primitive equipment and only lost his touch later in life. Probably due to failing eyesight. A 5-inch lens of Mellish's is at the Questar Corps. It was tested by professional optician Paul Shenkle while employed by Questar (now Davro Optical Systems). Shenkle stated it tested perfect - no zones, excellent figure and polish. Mellish's largest lens was 12-inches and his largest mirror 36-inches diameter. Another example of the high regard with which Mellish was held is that Professor Anderson of CalTech, in overall charge of the Hale Telescope project, invited Mellish to work on the 200-inch mirror. Mellish turned the offer down (although there are indications he may have later regretted doing so) stating he wished to remain independent and his own boss.
The following comments will conclude this reflection on Mellish. In correspondence dated 2nd. Feb. 1997, William Sheehan to whom I provided copies of Mellish's letters to Walter Leight some years before, states, and I quote, "There can be no doubt that Mellish was convinced he saw craters on Mars, nor is there any reason to impugn his honesty. Your explanation of the circumstances giving rise to his conviction - the perception of the variously mottled albedo features - is probably as good as any." Sheehan went on to comment that he hoped at a future opposition observers might get as good a view of Mars as Stephen James O'Meara had with the Mt. Wilson 60-inch reflector. Richard Berry, writing in Telescope Making magazine, #44 p31, stated that O'Meara awed his audience at the 1991 Florida "Winterfest" convention with his description of craters he had observed on Mars using the 60-inch.
And today that is where matters rest. Those who browse this web page are of course free to form their own opinions. It should always be remembered that allowances must be made for exceptional observers using excellent telescopes under exceptionally favourable conditions.
This page was created by SimpleText2Html 1.0.2 on 25-Feb-102.