In 1892, George Ellery Hale, a professor of astrophysics at the University of Chicago, convinced the university president to acquire two 40-inch telescope lens blanks. With funding from Charles Yerkes, a Chicago mass-transit tycoon looking to refurbish his image, Hale spearheaded the creation of an observatory to house the Great Refractor made with these blanks. Part of the terms of Yerkes’ financial backing was that the observatory be built within 100 miles (161 kilometers) of Chicago, so a location in Williams Bay, Wisconsin, 90 miles (145 km) north of Chicago, was selected and construction began in 1895. Parklike grounds were designed by the famous Olmstead brothers, and the building itself is ornately Romanesque. A 90-foot-diameter dome houses the famous 40-inch Great Refractor, which remains the largest refracting telescope in the world.
On Oct. 21, 1897, the observatory was formally dedicated. Over the next century, work done at Yerkes led to its recognition as the birthplace of astrophysics and a home for great astronomers, including Edwin Hubble, Edward Barnard, Gerard Kuiper, Carl Sagan, and Nancy Grace Roman. Although the University of Chicago’s attempts to sell the observatory in the first part of 21st century led to a long period of uncertainty, the Yerkes Future Foundation took ownership of the facility in 2020, with a focus on restoration, public outreach and education, and preservation of the historic site.
