Seth Barnes Nicholson

Seth Barnes Nicholson (November 12, 1891 – July 2, 1963) was an American astronomer. He worked at the Lick observatory in California, and is known for discovering several moons of Jupiter in the 20th century. Nicholson was born in Springfield, Illinois, and was raised in rural Illinois. He was educated at Drake University, where he became interested in astronomy. On May 29, 1913, he was married to Alma Stotts, a fellow student at Drake then the University of California at Berkeley. They would have three children: Margaret, Donald, and Jean. In 1914, at the University of California's Lick Observatory, while observing the recently discovered Jupiter moon Pasiphaë, he discovered a new one, Sinope, whose orbit he computed for his Ph.D. thesis in 1915. He spent his entire career at Mount Wilson Observatory, where he discovered three more Jovian moons: Lysithea and Carme in 1938, and Ananke in 1951. While at the Palomar Observatory in 1957, he discovered 1647 Menelaus, an asteroid near Jupiter. Other work included computing the orbits of several comets and also that of Pluto.