Dearborn Observatory,
Life Span: 1865-1886, 1889-Present (Evanston)
Location: Chicago University, 3400 S Cottage Grove
Architect: W. W. Boyington
University of Chicago and Observatory
Chicago Tribune, February 23, 1864
Astronomy is the first and last of the exac sciences. The earliest efforts of inquirers were directed towards te heavens, and the first records of civilizations are of celestial observations. Without instruments, destitute even of a knowledge of the geometrical elements, the heavens were mapped out and the courses of the stars rudely determined. The study has been prosecuted in all succeeding ages, and each new development gained in the other departments of scientific research, has been eagerly pressed into the service of the astronomer, until now the proper and accurate determination of astronomical problems involves an acquaintance with the sciences of chemistry, optics, the abstruse domains of the mathematics, geodesy. topography, meteorology, with many branches of higher mechanical art. It is this higher sphere of research that astronomical investigations become the ultimate object with our most distinguished savants, as it is also daily becoming more and more apparent that all the sciences are mutually dependent for their perfection; hence it is not only as it satisfies a vulgar curiosity or enables us to talk largely about unfathomable depths and the measureless void, but that it certifies and verifies our knowledge of the other physical sciences, and promises to aid us most materially in that least of all understood branch—meteorology. It is from this superior stand point that it comes last. The founding of an observatory involving all the points above mentioned, invariably and necessarily falls last in the march of intellectual activities. In England, France, Russia and America, this order os observable. Other educational institutions, other scientific discoveries and manipulative processes have first to attain a respectable magnitude ere the observatory can be founded, or the value of its silent watchings appreciated. It is thus that astronomy is at once the avant courier of civilization and brings up its rear guard. At first the shepherd’s picket was its only station. Then as Egypt rose, her pyramids were built with a view to astronomical observation, for we have lately discovered that the position of A Draconis—the then pole star—at the time of its erection. And now we see the very same order observed—the magnificently complete structure known as the modern observatory is the top stone, the crowning work of scientific civilization.
The citizens of Chicago may point with just pride to the fact that, although scarcely more than thirty years old, our city will soon be in possession of an observatory, and one which the peoples of any of the older cities might be proud to claim. It is one of the best possible proofs of her solid advancement in all the ennobles and elevates humanity. And true to her already earned character she is satisfied with no inferior instrument. The one now secured and in process of construction as the principal piece—the grand equatorial, is not only the largest but the best in the world. The building is already under way, and the year 1865 will not have passed before we have in full operation an astronomical observatory, not perhaps so complete in its appointments as some others but possessing the essentials of superior efficiency.
The History of the Movement.
The present movement, so magnificent in its design, is like many other great results—traceable to a very small beginning. It was proposed simply to provide an appendage to the University of Chicago, with which students there could gain an acquaintance with practical astronomy. The friends of the institution formed a Committee, and showed themselves willing to aid in the project, but were near being stranded by the puffing of a very inferior instrument—almost worthless—by some who sought to be interested in its sale. Fortunately, the contemplated foray was discovered in time, and the Committee, now reorganized on a better basis, determined to found an Observatory, on a scale commensurate with the educational standing of Chicago, and looked around for the best instruments. The plan of connection with the University retained, and the architect—W. W. Boyington—was dispatched East to examine the similar structures at Cambridge and Washington, while Messrs. J. Y. Scammon and Thos. Hoyne, secured the grand equatorial telescope. This instrument is nearly finished. It was commenced by Alvan Clarke & Sons, of Boston, for a Southern University (University of Mississippi), but when the war broke out the contract was annulled, and the telescope had lain for some time waiting a purchaser. The Boston savants were already partially negotiating for it, and had they supposed it possible that the prize would have been snatched from their grasp they would have secured it long before. They were much chagrined at losing it. Professor Mixer meanwhile was indefatigable in raising subscriptions, devoting all his spare time to that object, and through his exertions and the liberality of our citizens the money was raised in time for the first payment, and afterwards the whole of the money required for its purpose was procured. The building was then decided on. It was at first thought to place the telescope in the University tower, but the idea was soon abandoned when it was considered that sufficient stability could not be attained. The site chosen was on the west side of, and a few feet removed from, the main building, the two being connected by a corridor. The following is a section of the observatory tower.
Description of the Tower.
The tower consists essentially of two independent portions—the central pier, and the outer-building. Being near the lake shore, there is a deep layer of sand and clay which is unfitted for a foundation. To remedy this, one hundred and five oak piles have been driven twenty-seven feet into the earth, penetrating the clay and hard pan. An excavation is made to the depth of fifteen feet, or ten feet below water, and the piles are sawed off and capped with twelve inch square oaken timbers, well bolted to the piles and to each other, after which the interstices will be filled with concrete, and the entire surface floored over with oak timbers. On this will be commenced the masonry, composed of large solid blocks of stone, from four to five feet square, and twelve to eighteen inches thick, laid in a circular manner with the joists radiating from the center. This will be carried up solid to a height of twelve feet above the timber platform.
On this will be built the pier, or column, built like the frustrum of a hollow cone; twenty-seven feet in diameter at the base, eighty-two feet high to the top, or floor of the astronomer’s room, where it is ten feet in diameter. It is surmounted by a circular cap stone, sixteen inches in thickness, and on this will be the pedestal, or tripod, nine feet high, carrying the telescope, with its mountings, the instrument for whose proper working and preservation all the work is done. The foundations will be completed by the first of April.
The outside building or enclosure, will rest also on piles. It will be octagonal in shape, thirty-five feet in diameter, and one hundred feet high to the top of the semi-globular roof. This roof will be made to rotate on balls, and will be provided with a vertical cut of about twenty-two inches in width., so that the telescope can be pointed to any desired altitude as well as azimuth, while, by means of shutters, the building is kept perfectly closed, except just opposite the object end of the tube. The floors shown in the diagram will not touch the pier; they will be kept away some distance so as to avoid contact when the outer walls are shaken by the wind, or deflected from the perpendicular by the heating influence of the solar rays.
Further to the westward of this tower, will be erected another, much lower, in which will be placed the meridian circle—an instrument designed exclusively for taking observations in the plane of the meridian, as for the determination of latitude, and noting the transit of stars across the meridian.
The Site.
The site thus chosen entails several disadvantages, which will require much care both now and in the future, to correct. The usual location of an observatory is a hill, or at least a rising ground where a low building will secure a good horizon. and obviate those deflections from the perpendicular which are so troublesome to the observer where that is not the case. Every precaution appears to have been taken thus far, but beyond this the process of observations needed to determine from a mean of several data the true quantity as uninfluenced by electric disturbance in the ground, by the vibration due to washing of waves, on the lake shore, and other elements of insecurity which are much magnified at great altitudes. We apprehend but little danger from shifting of the foundation.
The Telescope.
The telescope will be twenty-three feet in length, and have eighteen and three-quarters inches of aperture, fully two and a half inches greater than that of any other in the known world. Its total weight will be about six tons, or twice as great as that of the equatorial at Cambridge, Massachusetts. The tune will be of wood, veneered. Its cost, including transportation and mounting, will be $18,187, and it will be finished in June next, some time before the tower is ready for its reception. No extended description of its powers is necessary; they have already been published in our columns. Suffice it now to say that it will be mounted in a style worthy of its great defining powers, and fitted with a larger variety than usual of eye-pieces and micrometric appliances.
The instrument when finished and put in place will be not only the ornament of Chicago or Illinois, but of the whole American continent. Still it will require the presence of many accessories to develop its full efficiency. Other observing telescopes will be needed, much of apparatus, many books, tables and maps, a corps of observers. But no one can doubt that these will be long unsupplied. The genius of the West requires a little stimulus to exertion where the object to be attained is a proper one, and the public once awakened to a sense of the high results to be achieved, the prominent position to be attained by its use, will pour out money like water should that be needed to bring out the climax of its usefulness.
The University.
The University of which this is to be a part will be much increased in efficiency and value by the addition. The size of the building already erected and now in use is 560 by 90 feet on the ground floor, and known as the south wing and corridor; it is five stories high, and is designed for the dormitory department of the University, although now used in part for recitation and Professors’ rooms. It is now proposed to erect the entire set of University buildings during the coming season in accordance with the orignal plans, and proposals for the work are now invited. The size of the main building will be 120 by 90 feet; the north wing and corridor 66 by 90 feet; the north wing and corridor 66 by 90 feet, all four stories high except the corridor, which will be only three. The main tower on the east point will be 24 feet square and 152 feet high. The observatory on the west front will stand 100 feet from the main building. The entire set of buildings—like the portion already constructed, will be of stone, in the Norman style of architecture, quite irregular in its outline, with a sufficient number of towers and turrets to relieve the exterior from a stern plainness, forming, when finished, one of the finest sets of University buildings in the United States, both for its completeness of appointment and architectural appearance.
Western Monthly, March, 1869
The astronomical observatories of the world, about one hundred in number, are divided into three classes. The first class includes government institutions proper, like those of Washington, Greenwich, Paris and Pulcova, near St. Petersburg. Many-indeed, most of these— are on a very large scale; have very many instruments of the first class, especially meridian instruments , and employ the services of a numerous staff of astronomers. The second class is of observatories, like our own, attached to universities, or governed by boards of trustees, similarly constituted. These institutions are both scientific and educational, and have in fact, as a class, taken the lead in advancing the technical part of astronomy, in training observers, and preparing men to undertake the duties of astronomers in the richer and more extensive, but generally less progressive, establishments under government patronage. The rule is, without exception, that no observatory which is not at the same time an astronomical university—which does not teach both the principles of higher mathematics and the general outlines of astronomy itself, together with the special modes of using instruments–will be permanently celebrated by anything more than a mere accumulation of facts, and these, too, generally ill worked up.
For instance, the whole present system of observing astronomy grows out of the work done since 1814 by Bessel and Struve, at the two universities of Koenigsberg, in Prussia, and Dorpat, in the German province of Russia. The most celebrated astronomers now living-Airy, Argelander, the younger Struve, Hansen, Le Verrier-have studied in the school or after the methods of the two great men mentioned above; while in a similar manner the higher mathe matics of astronomy is largely due to the celebrated Gauss, formerly con nected with the university-observatory of Goettingen, in Hanover.
In our own country, the two colleges, Harvard and Yale, have trained up the majority of our astronomers; and in the West the University of Michigan called some years ago from Germany the distinguished astronomer Bruennow, who is now waking into a new life the old observatory of Trinity College in Dublin, but who has left with us pupils not un worthy of their teacher’s fame. Of the third class of observatories, those be longing to private individuals, little need be said here. They have very often accomplished brilliant work, but always sooner or later pass either into the hands of trustees, and thus become of essentially the same class as our own institution, or else their instruments are dispersed and their buildings dismantled, when the property passes into the hands of heirs who care little for astronomy. Sir William Herschel and the late Earl of Rosse were fortunate in having sons who have inherited their fathers’ taste for astronomy, and who have followed in their fathers’ steps; but there are other private observatories no longer heard of.
Any university in this country which is to really be worthy of the name should have an observatory attached to it ; for the very idea of a university requires that none of the sciences should be neglected or taught merely theoretically; and the science of astronomy has an exceedingly wide bearing. No first-class mathematician should be without something of an observatory training; and the very introduction of the higher mathematics into this country has been through the interest awakened in astronomical subjects. Mathematics, without its applications, is a noble science indeed, but seems foreign to the genius of the American people; the highest and and best of its applications, the one that requires the most of it and the deepest parts, is to astronomy. Newton and his contemporaries desired to solve the great astronomical problem of the solar system. One result was the differential calculus, which every good engineer employs now-a-days, at least in the more difficult questions. And so with the gradual improvements which have been introduced from time to time into mathematical science; they have generally come through astronomy; and from these elevated applications the problems of the universe have gradually come down.
It is very fit that the growing University of Chicago should have connected with it an observatory of the first class. The metropolis of the Northwest, great, and growing greater every day, is a most excellent center for the diffusion of ideas, as well as of agricultural products and manufactures; and the peculiar genius of the people of Chicago, combining the most active elements from many nations, is extremely favorable to the success of all well-judged attempts at higher culture.
Among the leaders of Chicago culture stands, quite prominent, the distinguished citizen, whose portrait is the frontispiece of this number, and his name is closely connected with the whole history of the Dearborn Observatory. It was decided, in 1862, that an Observatory should be attached to the University. It was found that a telescope by Fitz, of rather moderate dimensions, could be procured, and Mr. Scammon determined to build the tower for its reception, whose estimated cost then was less than ten thousand dollars. But shortly Prof. A. H. Mixer was sent to consult with Bruennow, then at Ann Arbor, and it was found that the great object-glass by Clark, the greatest refractor then existing, and with which the companion of Sirius had just been discovered, was for sale; and that other instruments, especially a first class meridian circle, were needed to complete the equipment of the Observatory. The Hon. Thomas Hoyne, also a distinguished trustee of the University, was sent to Cambridge, to negotiate for the purchase of the object-glass. He succeeded in this, by his energy and perseverance, in spite of considerable obstacles, as the Observatory of Harvard College wished to purchase the glass, and a subscription for that purpose had been set on foot; and the citizens of Chicago came forward and subscribed liberally for the glass and its equatorial mounting. The increased size of the instrument made the tower for its reception necessarily of larger size, and more costly; an additional increase in cost to nearly $30,000 was caused by the rise in the cost of materials and labor, and by unexpected difficulties in the working of the dome machinery. All this was paid by Mr. Scammon, and in addition he has continually supplied means for the carrying on of the Observatory, and advanced money necessary for other apparatus.
The principal building of the Observatory is the great Dearborn Tower, attached to the West side of the University. (The institution bears the family name of Mr. Scammon’s first wife, Mary Ann Haven Dearborn.) It is ninety-six feet high, and thirty
feet in diameter; it is founded upon piles driven into the blue clay to a depth of nearly thirty feet. Similar piles sustain the central pier for the instrument, so that, though not founded on a rock, the whole structure possesses the necessary degree of firmness and solidity, though elevated to a considerable height.
In addition to this, a small but very neat building has been erected for the meridian circle, a first- class instrument, made by the Repsolds, of Hamburg, and bought with funds largely presented by Hon. W. S. Gurnee of New York City; funds which have become insufficient for the purpose only by the effects of the war in raising the cost of exchange, and in impelling our government to tax the instrument nearly a thousand dollars in gold as duties. The institution now possesses the main instruments necessary for a complete equipment on a grand scale. It still lacks some minor apparatus, especially a sidereal clock and a chronograph, also spectroscopic apparatus. It is under the control of the Chicago Astronomical Society, composed of the contributors, with a board of directors, comprising the principal contributors, and some other gentlemen selected from the general body on account of special qualifications or interest in science. Of this board and of the society Mr. Scammon is president, and Hon. Thos. Hoyne, secretary. Its independence from the immediate control of the Board of Trustees of the University, while yet the two institutions work harmoniously together, appeared desirable from general considerations suggested by experience. There are several examples in Europe of such arrangements, which have in general so worked that the mutual relations of the bodies are harmonious, while the details can be arranged by each for itself.
What the work of the Observatory has been was, in part, hinted at previously; otherwise, the subject of sidereal astronomy, on a large scale, has been the principal one studied, and in this the nebulae are included. The beginning of any institution of the kind requires the training of assistants and young astronomers; the forming of definite plans of work, and their steady and regular execution; and in that manner, after a time, the effectiveness of the observatory can grow steadily from year to year.
A revision of the nebulae has been begun with the Great Equatorial, since it came in 1866, which has brought to light a good many new ones before unknown, together with interesting facts about the old ones, which have escaped the notice of former observers provided with less powerful telescopes, or with the more cumbrous great reflectors, which take so much time to direct to any point. With the same instrument over 3,000 stars in the Milky Way have been catalogued with great accuracy, and there can hardly be set a boundary to its usefulness in both these directions, if it is employed steadily and consistently.
The meridian circle, on the other hand, has also been steadily worked since its arrival in October last, and the preliminary observations necessary at first, upon a scheme for cataloguing the brighter stars originated by Argelander, and adopted by the German Astronomical Society; a society whose members are scattered all over the world, at least from Chicago to the eastern extremity of Europe, whose object is to combine the efforts of all astronomers in one grand whole. They will, it is hoped, take up the subjects which have employed the Great Equatorial in such a manner that those, too, may be pursued regularly in several observatories, dividing up the labor appropriately for each. In this case, the work which we can best do will be assigned to us; at present, the subjects of observation would require a lifetime to complete.
In conclusion of the present article which is to be followed by others more in detail-it may be stated that not merely the liberality which has equipped the Dearborn Observatory so munificently is to be commended, but that the breadth of the views which have brought forth the fruit of permanent institutions of higher culture in this city, is a most cheering sign that Chicago will continue to advance as well intellectually as in its material prosperity, as long as she can so proudly boast of such men at the masthead of her various institutions as J. Young Scammon.
Chicago Tribune, November 10, 1887
The Dearborn Observatory Dismantled.
The Dearborn Observatory was dismantled Tuesday by Profs. Colbert and Hough, the equatorial telescope being taken down. It was removed yesterday morning to the Home safety vaults at the corner of La Salle and Adams streets for safekeeping. The transit instrument has not yet been removed.
Chicago Tribune, April 22, 1888
The Dearborn Observatory
A joint committee representing the Chicago Astronomical Society and the Northwestern University was busy at Evanston yesterday examining plans and proposed locations for the Dearborn Observatory, in which is to be placed the big telescope formerly located at the Chicago University. The society was represented by Dr. H. A. Johnson, Prof. Mixer, J. Young Scammon, and Prof. Hough. The committee for the university was President Cummings, the Hon. J. B. Hobbs, Orlington Lunt, Prof. E. D. Sheppard, and Dr. Bonbright. It was agreed to locate the observatory on the bluffs about 400 feet north of the Swedish Seminary, and about midway between Chicago avenue and the lake. The observatory will be about 250 feet from the beach, experiments made by Prof. Hough having demonstrated that the waves made no impression at that distance. The plans as submitted by Cobb & Frost were adopted as a whole. Mr. Hobbs has donated the sum of $25,000, and at least that amount will be spent on the observatory building. The plans provide for a building 79×65 feet, facing the west. The observer will be twenty-seven feet above the ground, and the top of the dome will be about forty-five feet, the telescope rising fourteen feet ten inches above the floor. There will also be a library 20×30 feet inside and a room of similar dimensions over it, in addition to four large working rooms. It will take at least six months after the contracts are let to finish the dome.
Chicago Tribune, May 12, 1889
The Dearborn Observatory has just been completed. It is built of stone and in the most substantial manner. When viewed from the drive, with the lake for its background, it stands out in bold relief, and presents a singularly grand and beautiful appearance. The building includes a dome for the great reflecting telescope, which is one of the largest in the world. The observatory supplies time signals each day in the year by telegraph to Chicago and points throughout the West.
Dearborn Observatory
Evanston
1890
Chicago Tribune, September 12, 1897
Chicago has the singular distinction of having twice possessed an astronomical instrument admitted to be the biggest refractor and justly entitled to be called the best telescope of any class in the world. The “equatorial” of eighteen and a half inches aperture and twenty-three feet focal length which was mounted in the Dearborn Observatory in this city in March, 1866, “led all the rest” from that time till 1873, when two larger instruments by the same maker were finished for the National Observatory in Washington and for the University of Virginia respectively. Now the lost lead is retaken by the building of the Yerkes Observatory of the University of Chicago, near the northern extremity of Lake Geneva, in Wisconsin. The structure is equipped in part with a monster glass having a clear aperture of forty inches, mounted in a steel tube sixty-two feet long. The diameter of the opening
Chicago Tribune, March 23, 1939
Aerial view of Patten gymnasium of Northwestern university in Evanston and surrounding territory. Photo diagram shows how the gymnasium will be cut into three pieces and moved piece by piece to Lincoln street and Sheridan road to make room for the new institute of technology. The Phi Kappa Psi fraternity house and the Dearborn observatory also will be moved to new locations.
Daily Northwestern, April 5, 2022
Dearborn Observatory Reopens to Public After Two-year Closure
Jacob Wendler, Reporter
After going dark for two years, Dearborn Observatory will once again give amateur astronomers the opportunity to see space’s brightest stars in detail. The observatory reopened to the public Friday night after shutting down in March 2020 because of the pandemic and remaining closed throughout this past fall and winter for construction.
According to astronomy and physics Prof. Michael Smutko, observatory director, Dearborn is pursuing a “soft reopening” with public tours available on a reservation-only basis through June.
Beverly Lowell, a fourth-year astronomy and physics graduate student, said she enjoys connecting with the community as a host and tour guide at the observatory, which she has been doing since 2019.
“When someone sees Saturn or Jupiter through the telescope for the first time, even if they know what it looks like, seeing it with their own eyes is so special,” Lowell said. “The look on their face is priceless.”
Students and faculty in the physics and astronomy department often use the observatory, and classes like Astronomy 120: Highlights of Astronomy and Astronomy 321: Observational Astrophysics use the Dearborn telescope for observing sessions.
Beginning this summer, Smutko said the observatory plans to open for walk-in tours, which were held weekly before the pandemic and attracted over 1500 visitors each year. Undergraduate and graduate students host tours in all weather conditions, although visitors are advised to dress appropriately because the dome does not have heat or air conditioning.
Weinberg junior Jay Zou, who began hosting tours at the observatory in 2020 and now studies physics and astronomy, said he was inspired to get involved with Dearborn after participating in astronomy research in Colorado as a high-school student.
“I really love mentorship and teaching and just the thought of being able to potentially inspire young scientists from a diverse set of backgrounds,” Zou said. “I feel like it’s something that every scientist should do — you don’t just do science, but you also do outreach to the community.”
The tour experience includes a brief overview of Dearborn’s history and a chance to look through the observatory’s refracting telescope, which features an 18½ inch lens, which was the largest in the world from 1862 to 1868. The lens, built in Massachusetts for the University of Mississippi in the early 1860s, was first used by the University of Chicago in 1866 when the Civil War prevented it from being transported to Mississippi. After the original University of Chicago went bankrupt following the Great Chicago Fire of 1871, the telescope landed at NU in 1887, and it was originally housed at the modern-day site of the Technological Institute.
To make room for the Technological Institute, in 1939 the observatory was moved to its current location over the course of three months. The observatory’s current dome was installed in 1997 and refurbished the following year.
In its 135 years at NU, Dearborn has been the site of research on UFOs and continental drift as well as facilitated the discovery of over 100 binary stars and the first white dwarf.
Smutko said the upcoming total lunar eclipse that will be visible from Chicago on the evening of May 15 is an astronomical event community members can anticipate. The observatory plans to host an outdoor observing session for the event depending on weather and visibility, he said.
The observatory offers free tours every Friday night at 9 p.m. and 10 p.m. and members of the public can make reservations on the observatory’s website. While the observatory has already reached capacity for April tours, NU students, faculty and members of the community at large can make reservations for May and June.
“People can stay home in Google Images on the computer from Hubble Space Telescope and things like that,” Smutko said. “But coming and looking through an actual telescope is something that actually most of our visitors have never done, so we’re happy to give them the opportunity to do that.”
Dearborn Observatory reopens to public after two-year closure
The 18½ inch lens in Dearborn Observatory’s refracting telescope was the largest in the world when it was built in the 19th century.