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 the Planetary Patrol project, which helped determine Mercury's rotation period and monitored Jupiter's Great Red Spot while developing new photographic techniques for satellite searches. After retiring in 1973, he kept building telescopes and advocating for the study of unidentified flying objects until his death in 1997.