Members of the Astronomy Department standing in the Dearborn Observatory, Nov. 28, 1908. Courtesy of University Archives.
View more Observatory images >
Dearborn Observatory
One of the oldest landmarks on the Evanston campus is Dearborn Observatory, which traces its origins to pre-Civil War Mississippi.
University of Mississippi's Commission
In 1859, F.A.P. Barnard, president of the University of Mississippi, commissioned construction of an observatory lens that would surpass the 15-inch lenses at the Harvard College Observatory and the Pulkova Observatory in Russia. Lensmaker Alvin Clark of Cambridge, Massachusetts, crafted the 18-1/2-inch glass, which was made in Birmingham, England.
The lens, to be installed in an observatory structure erected at the Oxford, Mississippi campus, promised an image 50 percent brighter than Harvard and Pulkova, the two largest refractors in the world at the time. The lens would become the largest in the world, a distinction it held for many years.
But Mississippi's agreement fell through when the Civil War broke out. The lens never made it to the Mississippi observatory.
The World's Largest Lens Comes to Chicago
In 1863, the newly formed Chicago Astronomical Society bought the lens from Clark for $18,187. Because the society did not have an observatory, it promised the use of the lens to the original University of Chicago, which agreed to build an observatory.
Chicago lawyer J.Y. Scammon donated the money for the observatory tower and dome at 3400 S. Cottage Grove, Chicago. The lens was installed in 1864, and the facility was named for Scammon's late wife, Mary Ann Haven Dearborn, a descendant of Revolutionary War hero Henry Dearborn.
However, the original University of Chicago went bankrupt in 1887, and the Astronomical Society decided to move the telescope to Northwestern. It was installed in the new Dearborn Observatory on the Evanston campus in a building donated by J.B. Hobbs. It was built in 1889 on what is now the site of the Technological Institute. Henry Ives Cubb, who had designed the Newberry Library in Chicago, served as the observatory's architect.
Dearborn's refracting telescope was used by generations of astronomers to study the planets, discover hundreds of double stars and nebulae, and measure the precise rate of continental drift.
Moving and Renovating Dearborn Observatory
To make way for construction of the Technological Institute in 1939, the observatory was moved 664 feet southeast to its current location. The Herculean feat used 26 jackscrews to move the 2,500-ton stone structure. Horses were used with tractors to turn the winches.
The last major change to the observatory took place in 1997, when a new aluminum dome was installed atop the structure. Observa-DOME Laboratories in Jackson, Mississippi, fabricated the dome, completing a Mississippi-Northwestern connection that began 138 years earlier.
The new dome and other renovations to the observatory have enabled scientists and students to continue to use the telescope for teaching and research at a time when much astronomical study takes place on computer screens that are thousands of miles away from telescopes in remote sites or in outer space.