Yerkes Observatory

Yerkes Observatory went into operation in 1899 with the completion of the world's largest refracting telescope. This telescope has an objective lens with a diameter of one meter (40 inches). Due to problems inherent with lenses (difficulty in casting large disks of glass, chromatic aberration), this telescope remains the largest refractor ever built. The institution is named for Charles Yerkes, a Chicago industrialist of dubious character, who was persuaded by George Ellery Hale to finance the project. Many of the twentieth century's leading astronomical talents have worked at Yerkes. These include Edwin Hubble, Otto Struve, S. Chandrasekhar, and Carl Sagan.

The observatory is about 60 miles north of Chicago in the very pleasant rolling farmland of the upper Midwest. It is situated on the banks of Lake Geneva, a popular resort area in the summer and framed with intense multi-hued foliage in autumn. Unfortunately, its spectacular location presents observational problems, principally high humidity year round and snow in the winter.

Unfortunately, I was unable to see the telescope on my autumn visit. However, the exterior is so spectacular with its baroque facade that it was worth the trip just to see that. The dome housing the 40 inch refractor is shown in the picture on the left, while the dome in the second picture contains a 24 inch reflecting telescope.

As long as we are in the area, we might as well make a stop at the Adler Planetarium in Chicago. These two photographs were taken while the planetarium was undergoing renovation a few years ago The sundial has since been moved from the location shown here. As it was, the sundial nicely framed the Chicago skyline with the Sears Tower in the center. I attended a presentation after the renovations were complete and it is quite impressive. An interesting feature on Friday nights is "Friday Night Live" where images from a remote telescope are fed into the planetarium and projected on the dome.