Dinsmore Alter (March 28, 1888 – September 20, 1968) was an American astronomer, meteorologist, and United States Army officer. He is known for his work with the Griffith Observatory and his creation of a lunar atlas. Early life He was born in Colfax, Washington, and attended college at Westminster College in Pennsylvania. After graduating in 1909 with a B.S. degree, he married Ada McClelland. The couple had one child, Helen. Career Dinsmore performed his graduate studies at the University of Pittsburgh, and earned a master's in astronomy with additional studies in the field of meteorology. In 1911, he became an instructor at the University of Alabama, teaching physics and astronomy. The following year he became an assistant professor, then an adjunct professor in 1913. In 1914, he moved to the University of California in Berkeley, teaching astronomy while also studying for his doctorate. He gained his Ph.D. in astronomy in 1916. By 1917, he became an assistant professor of astronomy at the University of Kansas. However, when the United States entered World War I, he took time off to serve as a major in the United States Army. After returning home following the war, he rejoined the University of Kansas and remained at that institution for nearly 20 years. He was promoted to assistant professor in 1919, then professor in 1924. From 1925 until 1927, he served as the vice-president of the American Meteorological Society. He was then awarded a Guggenheim Fellowship scholarship and spent two years studying astronomy in Britain. In 1935, he took a leave from the University of Kansas and became director of the Griffith Observatory. A year later he resigned his professorship to remain director at the observatory. He also served as a research associate at Caltech in Pasadena during the same period. After the U.S. entered the Second World War, Dr. Alter took a leave from his position to serve in the armed forces for four years. He became a colonel and served in a transport division. He remained a member of the army reserve following the war, training at Fort MacArthur, Los Angeles. His earlier studies had focused on solar observation, but after the war he concentrated on the Moon. As his expertise increased, he became an authority on the geology of the Moon, including its surface and history. He also remained involved in astronomy research, and in 1950 he served a term as