Our Pick
Posted on @rawstates
Yerkes, the last of the great refractors
1897
Williams Bay, Walworth County, Wisconsin
Public domain · Wikimedia Commons
The 40-inch lens here is the largest refractor ever successfully used for astronomy, and it always will be: a lens that size sags under its own weight, so every telescope built after it uses mirrors instead. George Ellery Hale founded the place in 1892 on money from a Chicago streetcar magnate who wanted his name on something, and it called itself the birthplace of modern astrophysics with some justification. It sits on a bluff over Geneva Lake because the air was steady and the railway from Chicago was convenient.
That was 1 of the hidden places.
Location: documented spot
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