This weekend, I was in Williams Bay, Wisconsin at a “campout” with my two sons. We didn’t actually camp (we stayed in dorms at the George Williams College campus of Aurora University), and our times out consisted of going back and forth between buildings on the campus (mostly the dining hall and the gym) and a few hikes.

Two of the hikes took us to the Yerkes Observatory, a beautiful and historic building on an adjoining property owned by the University of Chicago.

Yerkes Observatory

The building dates back to the late 1890s and was built shortly after the university was founded. The large dome houses a 40-inch refractor telescope, once the largest telescope in the world and still the largest refractor.

We weren’t able to go into the observatory either of the times we were there: a notice on entrance said it wasn’t open Saturday night because of poor viewing conditions (there were a few scattered clouds, but I’m guessing it was the full moon that made the conditions poor), and it’s generally not open to the public on Sundays. The notice did give the address of the observatory’s web site, which I wrote down in my HPDA and visited this evening. It has a wonderful history section and a (90s era) “virtual tour.”

(Photo from the University of Chicago.)