Maria Mitchell

19th-century astronomer, Maria Mitchell.
Credit: Nantucket Historical Association

Born in Massachusetts in 1818, Maria Mitchell's thirst for knowledge and her interest in astronomy were stimulated by her father. He encouraged her to independently explore the mechanics of his telescope and also let her aide him with his work on chronometers (devices that allow ships to accurately measure time). Growing up, Mitchell and her father would conduct astronomical observations together. She became so well-versed with the night sky that by age 14, she had gained the respect of sailors who trusted her to do vital navigational computations for their long whaling journeys. Later in life, the U.S. Nautical Almanac asked her to track the position of Venus to help with navigation at sea.

From 1836 to 1856, Mitchell was a librarian at the Nantucket Atheneum, and during this time she continued observing the night sky. On one of these observing nights in October 1847, Mitchell spotted a curious object in the sky. Using a telescope on the roof of the Pacific National Bank on Nantucket's Main Street, Mitchell had discovered a new comet. This comet was later nicknamed Miss Mitchell's Comet (its official name is now C/1847 T1). This discovery lead to a newfound fame for Mitchell who reportedly did not appreciate all the attention as it distracted her from her work.

When Vassar College opened in 1865 in Poughkeepsie, NY, Mitchell was asked to be one of its first professors. Along with being a professor of astronomy, Mitchell became the director of the Vassar College Observatory. Her work focused primarily on planetary and solar astronomy, but she studied nebulae and double stars as well. In 1869, she brought her students on a trip across the country to observe a total solar eclipse in Burlington, Iowa. Talk about a dedicated educator! Mitchell was an avid solar observer and constructed an apparatus that allowed one to safely image the sun. From her observations, she was the first to uncover that sunspots (those dark spots one sees pop up on the solar surface) were vertical cavities rather than clouds.

The Hexagon, Mitchell's senior astronomy class at Vassar College, 1868. Mitchell's successor, Mary Whitney, is seated in the center.

Credit: Vassar College

In 1873, she co-founded the Association for the Advancement of Women which helped to improve the rights of women in the late 1800's. After retiring from Vassar College in 1888, Mitchell asked one of her former students, Mary Whitney, to take her place. The impact Mitchell left on the field of astronomy is evident by the fact that a lunar crater is named after her as well as an asteroid (discovered in 1937, it is named 1455 Mitchella). In addition, the Maria Mitchell Association was established in 1902 to preserve her extraordinary legacy (see post on Mary Albertson).