Dearborn Observatory

Circumstances that led eventually to the establishment of the Dearborn Observatory at Northwestern were initiated in December, 1862, when the Reverend M. R. Forey visited Chicago to deliver a public lecture entitled “The Sidereal Heavens.” The lecture convinced a group of prominent Chicagoans that the city’s cultural aspirations required the acquisition of a telescope. In 1867 these men founded the Chicago Astronomical Society and learned about a high-quality lens that might be available.

Before the outbreak of the Civil War in 1861, Frederick A. P. Barnard, the chancellor of the University of Mississippi (later president of Columbia University and founder of Barnard College), decided to establish an observatory. He commissioned the firm of Alvan Clark and Sons of Cambridge, MA, to construct an 18½” lens, which would make it the largest in the world. Clark crafted the lens, but war broke out before it could be delivered to Mississippi. The lens remained in the Clark workshop and Clark himself used it to verify that the star Sirius had a companion star, a discovery that won Clark world-wide recognition.

When the Chicagoans learned that the lens was for sale, they had to act quickly, because Harvard was already trying to acquire it. In January, 1863 the Chicago agent, Thomas Hoyne, arrived at Alvan Clark’s home to find that the lens had been packed for shipment and Clark gone to finalize the deal with Harvard. Hoyne jumped into a carriage, intercepted Clark, and, taking advantage of Harvard’s lack of cash, induced Clark to part with the lens for $11,187, with an initial $1500 in cash to seal the deal.

The committee was intent upon affiliating the nascent observatory with the original University of Chicago (1857-1886), located on South Cottage Grove Avenue. J. Young Scammon funded the tower to house the new telescope, in exchange for having the facility named for his deceased wife, Mary Ann Haven Dearborn. Construction began in 1863, and when completed two years later Dearborn Observatory was a medieval-like structure with crenellated walls and a tapering tower to hold the telescope, a walnut-veneered tube poised on an equatorial mount.

The committee appointed Truman H. Safford, University of Chicago professor of astronomy, as the observatory’s first director in December, 1865. For over ten years from its installation, the lens remained the largest and best in the world, and even today it is considered one of the finest astronomical lenses. Although it was chronically short of funds, the observatory contributed greatly to the United States’ growing reputation in astronomy. The Chicago Fire (1871) bankrupted most of the observatory’s chief backers and the panic of 1873 further compromised funding. In 1875 Dearborn bolstered its revenues by supplying precise readings of the time to a number of important local entities like the Board of Trade and the Elgin Watch Co.

The University of Chicago, however, was unable to put its financial affairs in order. In 1881 it opted to sell its astronomical equipment to the Chicago Astronomical Society. The University was finally compelled to declare bankruptcy in 1886, and the following year the Chicago Astronomical Society sought a new home for its equipment. On August 10, 1887, the Society signed a deal with Northwestern University to bring the telescope to Evanston. Northwestern Trustee James B. Hobbs volunteered to fund a new building for $25,000; the architecture firm of Cobb & Frost designed the building under the supervision of the Society and Northwestern president Joseph Cummings. The cornerstone for the new Dearborn Observatory was laid on June 21, 1888, and the dedication took place on June 19, 1889. The eminent astronomer George Washington Hough, who had been appointed director of Dearborn Observatory in 1879, continued in that capacity at Northwestern until his death in 1909. The affiliation between Northwestern and the Chicago Astronomical Society continued until 1930, when the Society relinquished all title to the equipment.

In the summer of 1939, Dearborn Observatory had to be moved to make way for the construction of the Technological Institute. Twenty-six men using 600 jacks hoisted the massive structure three feet off its foundation; the building was placed on rollers and pulled over tracks 664 feet south by a tractor and two teams of horses. The move to the new location took three months. The Observatory experienced another metamorphosis in August, 1997, when it was crowned with a new, 38-foot aluminum dome. It was also equipped with a new electronic gear system to manipulate the dome and telescope, which had previously been moved by a hand crank.

The building at the base of Dearborn Observatory’s dome, renovated in 1985, holds a research and historical library, with a reading room on the first floor, and on the second a storage annex with more stacks and classroom space. There are also offices on the first and second floors.

Dearborn Observ., Exterior: Postcard
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Quick Facts

Date: 1889

Architect: Cobb & Frost

Named for: Mary Ann Haven Dearborn

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