Clyde Tombaugh

Born in Illinois in 1906 and raised on Kansas farms, Tombaugh taught himself astronomy and optical engineering, grinding lenses by hand and building his own telescopes from spare parts. His homemade work earned him a position at Lowell Observatory in Flagstaff, Arizona, where photographic surveys of the night sky led to the detection of Pluto in 1930 — the first object discovered in what would later be recognized as the Kuiper belt. Over the following decades he identified hundreds of asteroids, star clusters, galaxies, and variable stars. As a professor at New Mexico State University, he led…