At this point David Schramm at UC called me up and asked me if I would be interested in a professorship, so I came back to Chicago in 1982. By 1983 there was a move to do something that would strengthen the astronomy being done at the University of Chicago, such as building a telescope. And the Dean, Stuart Rice, encouraged us to enlarge our vision. We said we would be happy building instruments and letting other people use them in exchange for their telescope time. He said, “Why don’t you just build a telescope?” So he became a principal board member in setting up the 3.5 meter telescope at Apache Point, near Sunspot, New Mexico, the construction of which I led.

Apache Point Observatory Model: Astronomer Donald G. York and David Cole pictured with an architectural model of Apache Point Observatory.
Credit: University of Chicago Photographic Archive, apf6-04345, Special Collections Research Center, University of Chicago Library

Spectrograph: Shawn Callahan, a Yerkes Observatory engineer, with the Echelle spectrograph at Apache Point Observatory.
Credit: University of Chicago Photographic Archive, apf6-04343, Special Collections Research Center, University of Chicago Library

The building of the telescope took some time because of problems building mirrors and such. We were building something completely new and it just took time. During this time we formed a cadre of people who worked well together including Rich Kron, an astronomer at the University of Chicago; Jim Gunn, an astronomer at Princeton University; and me. We started having discussions about a new project that would take advantage of what we had learned on the 3.5 meter but would open up a new way of asking questions.

This discussion led to the SDSS Project which started observations in the year 2000. While SDSS was not a part of the original vision for Apache Point Observatory, the experience and technology we developed led directly to the SDSS project.