History of Yerkes Observatory

There is a lot more history in our Virtual Museum.

Hale and Yerkes

The Yerkes 40-inch Refractor owes its existence to George Ellery Hale (1868-1938), a pioneer in astrophysical research.

From childhood, Hale was fascinated by astronomy; he was particularly interested in learning about the Sun and developed new instruments for photographing it. Following graduation from the Massachusetts Institute of Technology, Hale was accepted as a faculty member at the newly founded University of Chicago.

In 1890 Hale learned that the University of Southern California planned to build the world's largest telescope, using glass disks cast by Mantois of Paris and polished into 40-inch lenses by Alvan Clark and Sons in Cambridgeport, Massachusetts.

When the University of Southern California abandoned the project for lack of funding, Hale urged the University of Chicago to acquire the lenses and construct the telescope and an observatory. He and William Rainey Harper, president of the University, approached transit tycoon Charles Tyson Yerkes, who agreed to fund the facility.

Charles Tyson Yerkes, and William Rainey Harper.

Selecting a site

Hale sought a location close to the University but beyond Chicago smoke and haze. In addition to studying traditional night-time objects, Hale and his colleagues wished to do solar research. John Johnston, Jr., had given the University a 53-acre tract of land, about half a mile north of Geneva Lake. Observing conditions were equally good day and night, and a railroad line already ran from Chicago to Williams Bay, offering easy access to the University of Chicago. The site was chosen and construction began in 1895.

Building the Observatory

Warner and Swasey of Cleveland built the mounting for the telescope and a 90-foot diameter dome to house it. They also constructed a 75-foot diameter movable floor that raises astronomers to the telescope eyepiece.

Hoisting the polar axis for the 40-inch Refractor, 1896.

The Observatory nears completion, October 1896.

Yerkes Observatory was completed and dedicated in 1897. It was built in the shape of a cross, with two smaller domes for additional telescopes at the end of each arm.

The building and its contents constitute a fascinating example of the architecture and technological accomplishments of the late 19th century. Pictures of some of the detailed architecture can be found on the page dedicated to such detail.

Many famous scientists have worked at Yerkes or with collaborators here. This Observatory staff picture from 1914 includes several notable astrophysicists, including Edwin Hubble, who got his PhD while at Yerkes Observatory.

The Astrophysical Journal was founded at Yerkes by Hale and James Keeler in 1895, and it is even still an important journal in astrophysics -- as well as still published by the University of Chicago Press. For a nice article on the history of ApJ, see this article, by Donald Osterbrock.

This page concludes the section of the tour that most closely represents what you'd see if you came for a real tour. The advantage of this virtual tour, however, is that it can let you see a little behind the scenes! This Observatory has been a working research facility for more than 100 years.

You can learn about some of the science at Yerkes by checking out the overview of famous research done at Yerkes in the past, as well as an overview of research being done at Yerkes today.


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Content originally generated in March 1995.
This file was last modified on 20 April 1999.