The Lowell Observatory was founded in 1894 By Percival Lowell. The first permanent telescope, a twenty-four-inch refractor built by Alvan Clark and Sons, was installed in 1896 and is still in use. There are other telescopes at the site, including the thirteen-inch refractor used to discover Pluto in 1930. The Slipher Building is named for V.M. Slipher, the Observatory's director after Lowell's death. It houses various pieces of equipment, including the spectrograph Slipher used to determine that the universe is ... (more)