The Bruce Medalists


  portrait Photo 1948, Special Collections Research Center, University of Chicago Library.
Alfred Harrison Joy
23 Sep1882 1950 Bruce Medalist 18 April 1973

After earning his bachelor’s degree at Greenville College in Illinois and his M.A. at Oberlin College, Alfred Joy taught ten years at the American University of Beirut, where he photographed Halley’s Comet in 1910. He spent several summers and one year at Yerkes Observatory and also studied for short periods at Princeton (under Henry Norris Russell) and several European observatories. When World War I prevented his return to Beirut in 1915 he joined the staff of Mt. Wilson Observatory. He remained active there nearly sixty years, although officially retired after 1948. After early solar work with G.E. Hale’s team, Joy applied Walter S. Adams’s method of spectroscopic parallax to determine the distances of thousands of stars. When he retired nearly half of all published radial velocities of stars had been found at Mt. Wilson, largely through his efforts. He measured radial velocities of Cepheid variable stars and confirmed the distance and direction of the Galactic center and the sun’s rate of revolution about it. He specialized in the spectroscopy of variable stars, and also studied spectra of comets and novae. He invented the classification of T Tauri stars and made extensive studies of them. He edited the popular Leaflets of the Astronomical Society of the Pacific from 1945 to 1968.

Presentation of Bruce medal
Trumpler, Robert J., PASP 62, 33-36 (1950).

Some offices held
American Astronomical Society, President, 1949-52.
Astronomical Society of the Pacific, President, 1931, 1939.

Biographical materials
Bitterman, Jay, Lake County Astronomical Society
Huntington LIbrary, with Finding Aid to papers
Wilson, O.C., Biographical Memoirs of the National Academy of Sciences 47, 225-47 (1975).

Abt, Helmut A., Mercury 2, 3, 15 and 2, 5, 9-10 (1973).
Herbig, George H., QJRAS 15, 526-31 (1974).

AIP Center for History of Physics
90th birthday photo, 1972, courtesy Observatories of the Carnegie Institution of Washington

Named after him
Lunar crater Joy
Minor Planet #11769 Alfredjoy

More references

The Bruce Medalists

Please send comments, additions, corrections, and questions to