Yerkes Observatory: A Wisconsin Science Temple

Did you know the world's largest refractor telescope is located in southern Wisconsin? The Yerkes Observatory was built in 1897 in Williams Bay, on the northern shore of Lake Geneva, Wisconsin.  Although it is now past its prime for making major astronomical discoveries, today it is a really neat museum and education center.  Danielle and I visited it last year, and I thought I would record a few interesting photographs and tidbits here that might not be found on Wikipedia (where you can go and learn that the Observatory and nearby Frozen Lake Geneva were used as filming locations for Chain Reaction (1996), starring Keanu Reeves and Morgan Freeman).  They typically only provide free tours of the observatory on Saturday mornings, so you have to plan ahead a little bit if you want to visit.

The main telescope itself is quite impressive in scale, as you can see compared to the spiral staircase in this photograph.  Don't leave your jacket in the car if it is a cold morning, because the dome is kept unheated.  This is both because it would be too expensive to heat the dome, and to improve the astronomical viewing conditions by avoiding the atmospheric turbulence that would be caused by warm air escaping the open dome by convection.

Even Albert Einstein (middle right) managed to make a pilgrimage to the Yerkes Observatory in 1921.  It is obvious by comparing this photograph to the previous one that the floor is at different levels with respect to the bottom of the dome.  The entire floor in the room is actually a giant elevator.  Depending on the angle of the telescope, the viewing end changes height.  The solution that the engineers devised is to raise and lower the floor to reach the business end.  The electric motors that lift the floor elevator are still in working condition, and you can ride it up and down on the tour.

Here is a picture of one of the massive counterweights and pulleys that helps raise and lower the floor of the observatory.  There are several of these distributed around the circumference of the room.

The architectural details are fantastic and full of astronomical symbolism, some of which will be described by the tour guide.  It is pretty neat how the lobby hasn't changed very much from how it was at the end of the 19th century.

If you take a tour, make sure to keep an eye out for Spiderman hanging out in the rafters of the dome!