Today in the history of astronomy, the historic observatory in Williams Bay, Wisconsin, opens its doors.

| Published: October 21, 2026

The Yerkes Future Foundation has given Yerkes Observatory a new lease on life, aiming to preserve the historic facility and focus it on education and outreach. Credit: Astronomy: Samantha Hill

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.…