1401 Observatory Dr. Built 1878-81 National Register of
Historic Places David R. Jones
15.6-inch lens
The observatory was a gift from former Gov. Cadwallader Washburn, who stipulated that the
telescope had to be larger than Harvard University's 15-inch instrument.
Over the years, the Washburn Observatory was a means for important discoveries. One amateur
researcher used it to judge the weight and size of stars in the 1920s. Later, a UW researcher
determined the size of the Milky Way galaxy and judged the sun's location within it. Modern
astronomers still use those calculations.