Yerkes Observatory

Operated by the University of Chicago at Williams Bay, Wisconsin

One of many astronomical observatories throughout the world, it claims to be "the birthplace of modern astrophysics". Completed in 1895 with a lens diameter of 40 inches, the Yerkes remains to this day the largest achromatic refracting telescope used for scientific purposes.

The 40-inch Diameter Refracting Telescope

                                         1897 Photo                                              2006 Photo

     

In addition to its distinction as the largest it may also be the one with the most colorful history. It was financed by a known criminal, Charles Tyson Yerkes. Astronomer George Ellery Hale convinced the convicted but wealthy embezzler to finance the telescope, regardless of cost, providing that it be the world's largest. Which, indeed, it was. And so it bears his name.