Hoffleit, Dorrit, 1907-2007

Ellen Dorrit Hoffleit was born on March 12, 1907, on her parents' farm in Florence, Alabama. Her parents, Fred and Kate Sanio Hoffleit, had emigrated from Germany, and her father worked intermittently as a bookkeeper for the Pennsylvania Railroad. While he preferred farm work, it was not possible to support the family this way, and they relocated from Alabama to New Castle, Pennsylvania. Fred Hoffleit later returned to the farm, while his wife opted to remain in New Castle, judging that the educational opportunities for Hoffleit and her brother Herbert were better there. Hoffleit thus spent most of her early childhood in New Castle, and her interest in astronomy began there, as she would watch the night skies in their back yard with her mother and Herbert. In 1920, Hoffleit and her mother moved to Cambridge, Massachusetts, accompanying Herbert, who enrolled at Harvard University.

Hoffleit received her B.A. in mathematics from Radcliffe College in 1928. Her original plan was to teach high school mathematics, but as no jobs in this field were available, she obtained work as a research assistant at the Harvard College Observatory, working on the discovery and light curves of variable stars and earning 40 cents an hour while men doing similar work were paid a dollar an hour. While working at the Observatory, she took graduate courses at Radcliffe, receiving her M.A. and Ph.D. in astronomy in 1932 and 1938, respectively. She was the fifth woman to receive a Ph.D. from Radcliffe and was awarded the Carolyn Wilby Prize for best original work in any department for her dissertation on the determination of spectroscopic absolute magnitudes of southern stars.

When the United States entered World War II, many of the men at the Observatory joined government research organizations, while Hoffleit initially took on additional tasks created by the men's absence. In 1943, she joined the Ballistic Research Laboratory at the Aberdeen Proving Ground in Maryland, where she calculated trajectories for missiles. The director of the laboratory did not permit women to hold professional ratings, but ultimately professional ratings were awarded to eligible women. After the war, Hoffleit deferred her full-time return to Harvard and remained at the Proving Ground for an additional three years, working on the determination of trajectories of captured V2 rockets. She remained a consultant for the Research Laboratory until 1961.

In 1948, she returned to full-time work at Harvard and remained there until 1956, when she was named director of the Maria Mitchell Observatory in Nantucket. (She did not actually begin work at the Observatory until 1957, as the previous director, Margaret Harwood, had requested an extension in order to complete a project. In the interim, Hoffleit taught astronomy part time at Wellesley College.) Her job at the Observatory was a half-year appointment, and for the remaining six months of each year she worked as a research associate in astronomy at Yale University, running its star cataloging program. In 1964, she edited the Catalogue of Bright Stars, which listed stars visible to the naked eye, and she also edited a 1983 supplement.

Upon beginning work in Nantucket, she developed a research program for female undergraduates, with two to six students a year spending the summer at the Observatory. (Towards the end of her tenure at Nantucket male students were also included.) The students conducted seminars and open nights for the general public and for school-age children, photographed and studied variable stars, and presented the results of their research at annual meetings of the American Association of Variable Star Observers. Several of her summer assistants became professional astronomers and many retained close friendships with Hoffleit. Her appointment at the Maria Mitchell Observatory continued until 1978.

Hoffleit officially retired from Yale in 1975, but even after retirement, she remained active in the field of astronomy, writing papers, frequently on women astronomers, and presenting at conferences. She was considered an expert on variable stars, the history of astronomy, and astrometry, a branch of astronomy which deals with the positions of stars and other celestial bodies. In 1987, the International Astronomical Union named an asteroid after her, in acknowledgment of her contributions to the field of astronomy.