Uncle of Andrew Common, Founder in 1848 Matthew Hall Engineering
South Bank, Regents Park, St. Johns Wood, 1868
Two years later on the 9th June 1876 he was elected a Fellow of the Royal Astronomical Society. His passion for Astronomy had not diminished and he was beginning to be recognised as someone who would make important contributions in the field. The other Fellows of the Royal Astronomical Society warmed to him not only for his ability but also for his larger than life personality. It was in their company that he felt most comfortable and where he gained a number of lifelong friendships. This is evident by the warmth and affection leading astronomers like the Sir Frank Dyson, Henry Hall Turner and others had for him.
Ealing
In about 1876, Andrew Common moved from his house near Regents Park, to No. 63 Eaton Rise, Ealing, where he remained for the rest of his life. His occupation at this time was given as Electrical Engineer and Lead Manufacturer. The later censuses of 1891 and 1901 show the transition between Andrew Common’s association with Matthew Hall & Co., and his passion for Astronomy. The 1891 Census gives his occupation as Building Contractor and Astronomer; whilst 10 years later his sole occupation has become that of a Telescope Maker and Employer of Workers.
Eaton Rise, Ealing, c1910
Sometime around 1890 Andrew Common had given up working for Matthew Hall to concentrate all his efforts towards the construction of telescopes. It is likely that Andrew Common’s son Thomas took over the control of his great uncle’s company. Both the 1901 and 1911 Censuses states that his occupation was that of a Sanitary Engineer with the status of Employer. Thomas Andrew Common died in 1912, the year after the death of his mother Ann Common (nee Hall).
Telescopes
In 1877 Andrew Common decided to upgrade his equipment - a characteristic exhibited by almost every amateur astronomer. He purchased two 17 inch Glass Discs with the intention of grinding his own mirror and using them in a Reflecting Telescope of his own design. This idea was soon abandoned; instead he purchased an 18 inch Reflector from Mr. George Calver and attached it to a mount designed and constructed by him.
He put his new instrument to good use and by the following year, he had communicated to the Royal Astronomical Society the results of his observations of the outer satellite of Mars (Deimos) and the satellites of Saturn; in a paper published in the Monthly Notices for January 1878. However it soon became apparent that Andrew Common wanted to use his new telescope for astrophotography.
In the April 1879 edition of the Monthly Notices of the Royal Astronomical Society, he published two papers related to Astrophotography.
The first entitled ‘On the desirability of photographing Mars and Saturn at the next conjunction’. In this paper which he presented to the society the following extract is of some importance:
‘In the December 1878 Number of the Notices of this Society the particulars of the conjunction of Saturn and Mars on June 30, 1879, are given by the Astronomer Royal.
I trust that those astronomers who can will take advantage of this excellent opportunity of testing the relative actinic intensity of light of the two planets.
As they can then be taken under the same conditions, and if differently prepared plates are used—that is the ordinary wet plate and iodised collodion, and those dry plates that are more sensitive to the red rays—the different effects of the colours of the planets might be made apparent.
Perfection of image would not be of so much importance as the effect in producing chemical action on the plate.
To show the possibility of doing this, I beg to lay before the Society two photographic plates, one with a row of pictures of Jupiter (showing the effect of a slight difference in the exposure on the image both as to size and density), and the other a picture of Saturn, all taken with an exposure of about 2 ½ seconds in the case of Saturn, and still less in the case of Jupiter, by an eighteen-inch silver-on-glass Newtonian telescope.
March 1879.’
It therefore seems that by before March 1879 Andrew Common had used his 18 inch Reflector to obtain photographs of Jupiter and Saturn using Dry Gelatin Plates, and not the Wet Collodion plates (developed by Frederick Scott Archer). The photographs he obtained were too small to show any detail on the planet’s surface.
His second paper of April 1879 dealt with a subject for which Andrew Common true claim to fame as a ‘Great Astrophotographer’ lies – ‘Note on Large Telescopes with suggestions for mounting Reflectors’.
In this paper he considers the mounting of Reflectors and how best such a mounting should be constructed.
‘Having, then, by this process of selection got the silver-on-glass reflector on the Newtonian principle, it becomes necessary to consider the mounting; and here we come to what may be regarded as the vital point; for on the proper mounting of the reflector, so as to point it to any object in the heavens, and follow that object in its diurnal motion, while retaining all the conditions that are favourable to the best performance of the optical part, a great deal depends. As far as I know, no endeavour has been made to really find out these favourable conditions and make the mounting suit them, except in a partial manner.
I have endeavoured to find them out, and propose to indicate how they ought to be attained. They are as follows:—
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No tube properly so called;
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No mass of metal either below or at the side of the line joining the large and small mirrors;
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An equatorial mounting capable of direction to any part of the visible heavens, and of continued observation past the meridian without reversal;
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An efficient means of supporting the mirror without flexure;
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Driving clock. Circles to find or identify an object and conditions taken to eye end;
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A collimator for the ready adjustment of the mirrors;
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Such, a construction of mounting as to give the greatest mount of steadiness with the least amount of Motion;
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An effectual means of re-silvering the mirrors and of protecting them from dew;
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A safe, steady, and easily adjusted platform for observer, allowing about two hours' continuous observation without the necessity of any motion, except that from the observer’s place, and of ready access;
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A suitable locality for the erection of the telescope.’
The suggestions made by Andrew Common in this paper are of fundamental importance and are instrumental to achieving success in Astrophotography. He was the first person to stress the need for a steady mount fitted with an accurate motor drive; and the need for well balanced and collimated optics free from flexure. Without these criteria being met the chances of obtaining well focussed photographs of any astronomical object are at best minimal.
Andrew Common heeded his own advice and by July of 1879 he had obtained a new 37 inch mirror from George Calver, which he then mounted according to the principles he had outlined in his paper. The mounting he designed was a radical departure from the norm. It showed great engineering skill, and paid particular attention for the need to reduce friction between the moving parts. For example his design required the polar axis to be partly floated in mercury in order to reduce friction between adjacent surfaces. He also planned (but did not implement) for the use of an electric clock to accurately follow the movement of the stars caused by the diurnal motion of the Earth.
With the 3-foot reflector Common made visual observations of the satellites of Mars and Saturn, and the nebulosity embedded in brightest stars of the Pleiades.
In the ‘Observatory’ Journal of 1880, Andrew Common published further photographs of Jupiter now taken with his new 3 foot reflector on the 9th September 1879. The Editor noted the following:
‘We are Indebted to Mr. Common for the enlarged prints from photographs of Jupiter (Plate III.), taken with his magnificent 3-feet silver-on-glass reflector. Small though these photographs are, they give us much valuable information; and they have this great merit, as compared with the drawings of most observers, that they can be relied upon as accurate. It is little to the credit of those who attempt to make astronomical drawings, that a photograph less than 1/20th of an inch in diameter should be sufficient to expose the inaccuracies of drawings on 300 or 400 times the scale. In this connexion we would invite our readers to compare Capt. Noble's representation of Jupiter in the ' Monthly Notices' for January with Mr. Common's photograph of Jupiter and the Red Spot. The photograph of Jupiter and his four satellites is important, as showing the relative brightness of the satellites’ EDITOR.
36 inch Reflector at Ealing
He also obtained a photograph of a Comet on the 24th of June 1881, on the same night that it was photographed by Henry Draper in America. It was one of the earliest successful photographs of a comet.
Andrew Common's energies with his new telescope were however mainly devoted to the imaging of the ‘Great Orion Nebula’ (M42). His first attempt was on the 20th of January 1880, and was a total failure, but he patiently improved the driving of his clock and took advantage of each increase of sensitiveness in photographic plates till on the 17th of March 1882 he obtained a photograph "which excited the admiration of all the astronomers who had an opportunity of inspecting it’.
He still further perfected the guiding of his telescope, and obtained on the 30th of January 1883, with an exposure of 37 minutes, the splendid photograph with which all astronomers are familiar. Of the merits of this photograph he modestly remarked:
"Although some of the finer details are lost in the enlargement sufficient remains to show that we are approaching a time when photography will give us the means of recording, in its own inimitable way, the shape of a nebula and the relative brightness of the different parts in a better manner than the most careful hand-drawings."
He later on the 28th February 1883 obtained a photograph of M42 with a longer exposure of 60 minutes.
In 1884 Andrew Common was awarded the Gold Medal of the Royal Astronomical Society for his work on Astrophotography and in particular his photographs of the ‘Great Orion Nebula’.
‘Great Orion Nebula’ M42 Photographed by Andrew Common 1883
Shortly after he received the Gold Medal he sold his 3 foot reflector to Mr. Edward Crossley, a Halifax businessman and passionate amateur astronomer.
In the annual report of his Observatory at Ealing for the year 1884, Andrew Common remarks:
“During the past year a small number of celestial photographs have been taken, including two of the Dumb-bell nebula, and a number of experiments have been made in stellar photography.
The 3-foot Reflector has passed into the hands of Mr. Crossley, of Halifax, at whose Observatory it is now erected. It is intended to replace this instrument with one of 5-foot aperture, made expressly for photography, with a mounting having for the polar axis a hollow iron cylinder floating in water, so as to reduce the friction and vibration of a merely mechanical mounting.
The disk of glass for the large mirror was obtained in 1883, and seems to be all that can be wished for.”
36 inch ‘Crossley’ Reflector, Lick Observatory, Mount Hamilton, California
It is apparent that shortly after he had successfully imaged the ‘Great Orion Nebula’ in the March of 1882, he had been thinking about building an even larger reflecting telescope, and by the following year the plans for its construction were in place and the glass blank for his ‘monster’ 60 inch reflector had been purchased.
Schematic Drawing of the 5 foot Reflector
The construction of the 60 inch Reflector was to be the great work of his life into which he would put months and years of patient effort, hard work and great skill into its completion. The annual reports of Royal Astronomical Society on the work carried out by the observatories of its members provide valuable insight into the progress made by Andrew Common on the construction his 60 inch Reflector.
Andrew Common wrote in his report on the Ealing Observatory for 1885:
“Experiments in stellar and astronomical photography with various kinds of telescopes have been made. The De La Rue polishing machine has been removed from the University Observatory, Oxford, and erected in the workshop, and a temporary mounting and house is in the course of erection for further experiments.
A comet was found on the night of Friday, the 4th of September, and change of position noticed that evening. This proved to be a comet already found a few days before by Brooks in America. A series of observations were made on the Nova in Andromeda immediately after the announcement from Dun Echt.”
So during 1885 there was no apparent progress made on the construction of the 5 foot reflector apart from setting up the mirror polishing machine.
The report for the year 1886 is more positive and indicates that considerable progress had been made:
“The last year has been entirely devoted to the construction of the 5-foot reflector. The machine for grinding was completed in September, and great progress has been made with the mirror. Photography has been used to obtain permanent records of the state of the surface by using the reflected light from a pinhole (illuminated by a lamp), as in the system of testing used by Foucault. It is found that so small a quantity of light as can come through a hole .004 inch placed at the centre of curvature can be photographed in a few seconds after reflection from the surface.
A series of photographs have been taken from the first rough polish to the present state, and will be continued.
The kind of mounting has been determined upon, and the heavy work put in hand. It is hoped that the whole may now be completed without further delay.
The telescope is to be devoted to photography, and the mounting has been designed to give the greatest amount of steadiness and perfection of movement.”
The following year’s report for 1887 indicates that the construction of the telescope is nearing completion:
“Considerable progress has been made in the construction of the 5-ft. reflector. The mirror has been polished and figured several times in order to gain experience in the art. There is evidence of internal strain in the glass, which may or may not affect the image, and it is contemplated to order another disc in case this one does not permit of a good final figure.
The mounting is in a forward state, the telescope tube being connected to the polar axis, this latter being a wrought-iron
cylinder about eight feet diameter which will float in a tank of water, so as to relieve the friction in the manner mentioned in vol. xliv. of the Monthly Notices, p. 367.
The house or covering for the telescope, which will also carry the platform for the observer when the telescope is used as a Newtonian, is framed together and partly erected. It is hoped that the whole will be ready to use in the autumn.”
The telescope was finally completed in the September of 1887, as stated in the report for 1888:
“The 5-foot reflector was practically completed last September, and is now ready for work. On the few occasions that the weather has permitted, some trial photographs have been obtained that show a very satisfactory advance on those taken in 1883 with the 3-foot. It is intended to devote this telescope to the direct photography of the more important nebulae and to spectroscopic work on such objects as can be best observed with such an aperture.
The 6-inch achromatic is in good order. The transit instrument has been dismounted, and the room in which it stood used for a battery-room for two batteries of E.P.S. cells, available for lighting or power in the Observatory.
In the making of the 5-foot mirror much work was done of an experimental character in order to acquire the art of working glass. Many kinds of grinding and polishing substances, both for tools and for grinding or polishing the surfaces were tried, as well as different lubricants and methods of testing. From the experience thus gained a definite plan of working and testing curved surfaces has been arrived at that is very certain, a mirror of 30 inches diameter having been since figured in a comparatively short time.
In addition to the machine made for the 5-foot’s mirror, on which mirrors of smaller size can be figured, another machine has been erected for grinding and polishing mirrors under 30 inches, both curved and plane, with means for figuring mirrors of very short focus. It is intended to prepare some mirrors of about 20 inches diameter, with a view of finding the shortest focus that will work; as such mirrors might be of great use on nebulae, comets, and the corona during eclipse.”
However by the time of the next report for 1889, progress had been halted and if anything had gone backwards, as Andrew Common explains:
“The 5-foot mirror not being found on trial to be quite satisfactory, owing to the slight ellipticity of the image of a star, probably duo to the fact that the disc of glass had been resting in a sloping position for some years, was taken out in the spring and refigured and re-silvered; the image now given is very much better; owing to the very bad weather very little work has however been done with it yet.
The 20-inch mirrors mentioned in the last, report have been made, and two of them sent out to the Eclipse of December 22. As far as trials made before they were sent enable one to judge, such short-focus mirrors are likely to be very efficient. One is now being erected for regular use in the house lately covering the 6-inch achromatic which has been dismounted.
A new disc for the 5-foot telescope has been ordered and is expected shortly, as well as several discs of large size for plane mirrors. In view of the much better results that may be hoped for from the use of such piano mirrors as siderostats, particularly in eclipse and spectroscopic work in future, the making of plane mirrors of very large size is next to be taken up.”
After over four years of labour the 60 inch telescope was still not completed and a new mirror had to be ground.
Finally during 1890 Andrew Common was able to use it for its intended purpose, although the new mirror had not been ground and the inclement English weather was as is usual a key factor in dampening any adventure requiring its cooperation:
“The weather during the past year has been very unfavourable for observation at Ealing. Advantage has been taken of every available night, but the 5-foot telescope has only been in use 48 nights since March 1890, and only 24 of these were suitable for nebula photography. In all 31 photographs of nebulae and clusters have been obtained.
The principal nebula photographs are Orion 6 (one with 2 hours 35 minutes exposure, and one with 2 hours' exposure on plates stained with erythrosin; the first mentioned is much the best hitherto obtained); the Dumb-bell nebula 5 (the best with 110 minutes exposure on July 24, showing a large amount of detail) ; M 77, 3 (one with 150 minutes exposure, showing the spiral structure very clearly); M 99, 2 (with exposures of 2 hours and 2 ¼ hours, with spiral structure clearly shown) ; M 96, 1 hour; M 88, 1 hour; M 59 and 60, 2 hours 5 minutes; Gen. Cat. 4045,2 hours; Gen. Cat. 2203, 2207, 2211, 1 hour; and the Pleiades, 1 hour; showing nebulae. Amongst the clusters photographed may be mentioned those of M 2 (four photographs) and of M 5 (four photographs), the latter showing some new variable stars near the cluster; see Monthly Notices, vol. 1., page 519, June 1890. Photographs of the Moon have been obtained on nine nights during the year, and Uranus and its satellites have been photographed on two occasions.
Observations have been made of the satellites and general appearances of Saturn, Uranus, and Neptune whenever possible, the observations of Mimas being communicated to the Society in May 1890, and published in the Monthly Notices, vol. 1. Page 404.
A double wire micrometer, with position-circle and electric light illumination, has been made for the 5-foot telescope, and also a star spectroscope (which was supplied at the end of 1890) fitted with special apparatus for watching the slit during the long exposures necessary for photographing the spectra of nebulae.
Up to the present time, owing to bad weather, only preliminary work on the Orion nebula has been possible with the spectroscope. The spectrum of this nebula has been observed on three occasions (the only three possible since November), but no new lines have been detected.
As mentioned in the last report, the figure of the 5-foot mirror is not perfectly satisfactory owing to a slight ellipticity of the star images seen under high magnification, this ellipticity being probably due to the fact that the disc of glass rested in a sloping position for some years. The new 5-foot disc has been obtained from France, and the grinding of this will be proceeded with at once. Both the grinding machines have been kept in constant work.
A 36-inch mirror of 11 feet 3 inches focal length has been made for the Science and Art Department, South Kensington, and two 30-inch mirrors of the same focal length have also been finished, one of these being made with a spherical instead of a parabolic curve to be used in the testing of flat mirror surfaces. Another 30-inch parabolic mirror is now in hand and nearly finished. Two 20-inch mirrors of 45 inches focal length have also been finished during the year, and have been thoroughly tested in the 20-inch telescope erected in place of the 6-inch refractor.
A series of photographs of the Pleiades, the Dumb-bell nebula, of various clusters, and several photographs of the Andromeda nebula were taken with this telescope during the testing of the 20-inch mirrors, but the photographs have not yet been compared and measured. An instrument for rapidly comparing and measuring photographs, as described in the "Observatory," in August 1890, is almost completed, and will be used for a full examination of these photographs as well as for those taken with the 5-foot reflector.
A long series of experiments on the photographic determination of the reflecting power of silver, speculum metal, and silvered-glass surfaces (prepared by different silvering processes), and on the reflecting and transmitting power of plain glass have been carried on, but are not yet completed. The results will be communicated to the Society as soon as the experiments are concluded. A number of trials have also been made of various silvering processes, and a new process has been adopted by means of which a perfect film of any required thickness can be formed with absolute certainty, and mirrors of any size can be silvered with ease and rapidity.
The scarcity of good nights, partly due to the nearness to London, limits the use of the large telescope very much, and it is in contemplation to remove it to some more suitable position.”
The above account given by Andrew Common clearly shows that his new telescope was beginning to become useful, and had been used to take photographs of a number of the more well known Deep Space Objects; exactly the sort of targets the modern imager would choose – the ‘Dumbbell’ Planetary Nebula M27 in Lyra; the Seyfert Galaxy M77 in Cetus; the ‘Pleiades’ Cluster M45 with its embedded nebulosity; and the Globular Clusters M2 in Aquarius and M5 in Serpens Caput. He was however becoming concerned about the suitability of the telescopes location near to the London metropolis – he had taken note of the advice given in item No. 10 of his paper of April 1879.
The year 1890 was the best the telescope was to ‘see’ during Andrew Common’s lifetime, for the report given to the Royal Society in 1891 was in stark contrast to the one given the previous year:
“During the past year a new 5-foot mirror has been made for the telescope. This piece of glass has proved to be almost if not quite—perfect, and the mirror is a most excellent one.
Some very fine photographs of nebulae and the Moon have been taken, that will be laid before the Society.
A new grating spectroscope has been fitted to the 5-foot. Work on plane mirrors has been carried on in the workshop.”
That was all he said and the telescope was never used again, Why? There a number of factors why this proved to be the case.
Firstly, it is known that Andrew Common narrowly escaped a fall from a high platform when he was using the telescope as a Newtonian Reflector. This must have shocked him as such a fall could easily have proved fatal. He made some attempts to convert the telescope to a Cassegrain system, but the prospect of drilling a hole through the centre of the mirror he had spent so much time on – seemed not to be a good idea. An attempt was made to avoid this catastrophe in the waiting by devising a system where the secondary mirror was inclined so that the image was clear of the primary mirror. Despite some initial success the method proved unsatisfactory and Andrew Common abandoned the idea altogether and the telescope he had lived with for so long.
Secondly, the reports he prepared during the years the 60 inch reflector was undergoing construction, showed that it was not the only project with which Andrew Common was involved in. He was making mirrors for other people and for other projects. Not only that, but he gave generously of his time, expertise and money. If someone wanted a mirror made, Andrew Common obliged. For example he made two 20 inch mirrors for the Solar Eclipse of 1889, which he presented to the Royal Society; two 16 inch mirrors for the eclipse expedition of 1896 followed; as did a 30 inch mirror for the Solar Physics Observatory and in 1900 a 20 inch mirror for the National Physical Laboratory. The additional effort required to complete these ‘extra projects’ must have had a delaying affect on completion of his 60 inch telescope.
Thirdly, the concerns Andrew Common had for the sighting of his 5 foot reflector amid the ever increasing glow of nearby London must have weighed heavily on his mind, as must the poor weather England always faced!
After his death the telescope was sold to Harvard College Observatory and later sent to Bloemfontein in South Africa.
Andrew Common’s 60 inch Reflector, at Harvard College Observatory, c1910
However, the final reason for abandoning the 5 foot reflector was that Andrew Common found something to do which he considered more important.
Andrew Common became interested in developing telescopic gun sights for use by the Army and the Royal Navy. His knowledge of optics together with his great practical skills made him the ideal person to successfully see such a project to fruition. It is not known how he became involved in such a project, but it was in his nature to do something for the common good and not just for himself.
As regards its national importance the following words of Captain Percy Scott, R.N., spoken at a dinner at the Savage Club on 22nd of November 1902, will suffice:
"The nation owed a deep debt of gratitude to Dr. Common for the great improvements that he had made in gun-sights. It mattered not how good the gun was, nor how good a man there was behind it; unless the sight was perfect good firing could not be made. The great stride by the British Navy lately in that direction was entirely due to Dr. Common. ... He had produced a telescope gun-sight which would, when properly used, quadruple the fighting efficiency of our battleships”.
60 inch Reflector, Boyden Observatory, Bloemfontein, South Africa
Andrew Ainslie Common died suddenly of a heart attack in his study at No. 63 Eaton Rise, Ealing on the 2nd June 1903; he was nearly 62 years old. He was survived by his widow Ann (1840 – 1911) and their four children – Thomas Andrew Common (1875 – 1912), Violet Mary Common (1869 – 1952), Lillian Martha Common and Ida Common (1880 – 1951).
He will be remembered not only for his magnificent images of the ‘Great Orion Nebula’, but more importantly for the guidelines he laid down for achieving successful astronomical images and of course the two great reflectors he had spent so many years of hard effort in their construction.
It is fitting and entirely appropriate that these two telescopes are not only still in use but are in Andrew Common’s own words situated in ‘a suitable locality for the erection of the telescope’ amid clear dark skies - now far away from the cloudy nights in Ealing where they first saw the occasional light of the stars - which so lit up the life of their creator.
Notes on Andrew Common's Two Great ReflectingTelescopes
36 inch Reflector
In 1884 Common sold his 36-inch reflecting telescope to Edward Crossley of Halifax, Yorkshire, England. The weather in Halifax proved totally unsuitable for a telescope of this size and little use was made of it. As a result Edward Crossley donated the telescope to the Lick Observatory shortly after his retirement from astronomy in 1893. The Crossley 36-inch reflector at the Lick Observatory was the first of a long line of metal-film-on-glass modern reflecting telescopes that have dominated major astronomical advances for the past century. In addition, the Crossley has produced more scientific results than any other telescope of its size, including several historically important studies in stellar evolution, the structure and spectra of planetary nebulae, and the discovery and spectral analysis of faint variable stars in young clusters. The Crossley also contributed to studies that confirmed the expansion of the universe. Within a short time the Crossley reflector was put to good use when James E. Keeler initiated a program of nebular photography with it. Keeler's photographs showed the existence of hundreds of spiral nebulae that are now known as galaxies. Neither Keeler nor anyone else at the time realized that nebulae were predominantly extragalactic, but Keeler, using Crossley photographs, was the first to realize that these objects were a major constituent of the universe. After Keeler's death, astronomer Charles Dillon Perrine completed Keeler's observational program, and in 1908 published a remarkable selection of Crossley photographs in memory of Keeler. Keeler's and Perrine's success with the Crossley reflector was probably more influential than any other single factor in convincing professional astronomers of the practical effectiveness of large reflectors. By the early 1900s, as a result of Keeler's and Perrine's work with the Crossley, it was apparent that the future of large telescopes lay with mirrors rather than lenses. A few years later, when George Ellery Hale began to plan for the establishment of a large observatory on Mount Wilson in California, the use of a large refracting telescope was not even considered. The Crossley had shown the way to the future of astronomy. Large reflecting telescopes would now dominate 20th-century astronomy. The Crossley 36-inch reflector is found a few hundred yards southwest of the Main Observatory Building of the Lick Observatory and is still in use as an operational scientific instrument for the study of the stars and galaxies. The Crossley 36-inch reflecting telescope, at the Lick Observatory, marked the first modern application of a reflecting telescope to astronomical studies.
60 inch Reflector
Shortly after his death Andrew Common’s 60 inch Reflector was purchased in 1904 for the Harvard University Observatory, by its Director Edward Charles Pickering. He intended to continue using it for the Harvard photometry survey down to as faint stars as possible with the instrument. It was found that the definition was far from satisfactory, and in fact very little use was indeed made of it as around that time there occurred the rapid development of photographic stellar photometry, making visual techniques less attractive. However, Harlow Shapley who became Director at the Harvard College Observatory in 1921 required access to a large telescope to further his researches on the limits of the visible universe. The telescope was refurbished and sent to the Harvard’s Boyden Station in Bloemfontein, South Africa. It became fully operational in 1933. The funds for the renovation had been obtained from the Rockefeller family, and the telescope was renamed the ‘Rockefeller Telescope’. The ‘Rockefeller Telescope’ had an inauspicious start to life, but following its move to the Boyden Observatory it began to become useful, befitting a telescope with a 60” mirror. It is still in use today and actively participates in collaborative research projects with other astronomical institutions.
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