The Bruce Medalists


  portrait Photo 1964, courtesy Hale Observatories
Ira Sprague Bowen
21 December 1898 1957 Bruce Medalist 6 February 1973

“Ike” Bowen studied at the Houghton Seminary and Oberlin College. As a graduate student at the University of Chicago he worked with Robert A. Millikan, whom he accompanied to the California Institute of Technology. There he served as Millikan’s assistant, taught physics, researched cosmic rays, and earned his Ph.D. with an important dissertation on heat losses in the evaporation of water from lakes. His investigation of the ultraviolet spectra of highly ionized atoms led to his identification of the mysterious “nebulium” spectral lines of gaseous nebulae as forbidden lines of ionized oxygen and nitrogen. He soon explained most of the lines of gaseous nebulae. During World War II he was in charge of photographic work on the rocket project at the Jet Propulsion Laboratory. As director of the Mt. Wilson Observatory from 1946 to 1948 and of the combined Mt. Wilson and Palomar Observatories from 1948 to 1964, he directed the completion of the 200-inch Hale telescope and 48-inch Schmidt telescope and designed many of their instruments, including a novel spectrograph. He also initiated baking photographic plates to improve their sensitivity. He continued designing astronomical instruments after his official retirement.

Presentation of Bruce medal
McKellar, Andrew, PASP 69, 105-08 (1957).

Other awards
American Academy of Arts & Sciences, Rumford Medal, 1949.
American Astronomical Society, Henry Norris Russell Lectureship, 1964.
Franklin Institute, Potts Medal, 1946.
National Academy of Sciences, Henry Draper Medal, 1942.
Optical Society of America, Frederic Ives Medal, 1952.
Royal Astronomical Society, Gold medal, 1966, presentation by T.G. Cowling, QJRAS 7, 114-16 (1966).

Some offices held
Astronomical Society of the Pacific, President, 1948.

Biographical materials
Anonymous, “Dr. Ira S. Bowen New Director of the Mount Wilson Observatory,” PASP 58, 12-13 (1946).
Babcock, H.W., Biographical Memoirs of the National Academy of Science 53, 82-119.
Huntington Library, Biography accompanying inventory of scientific papers.
Osterbrock, D.E., Dictionary of Scientific Biography, 17, 95-96.
Wilson, O.C., “Retirement of Dr. Ira S. Bowen,” PASP 76, 193-96 (1964).

Aller, Laurence Hugh, QJRAS 15, 193-96 (1974).
Greenstein, Jesse L., Mercury 2, 3, 3-5 (1973).
Vaughan, Arthur H., Jr., Physics Today 26, 5, 77 & 79 (1973).
Wilson, O.C., Sky & Telescope 45, 212-214 (1973).
More obituaries

Caltech Archives (many)
AIP Center for History of Physics

Named after him
Bowen ratio
Lunar crater Bowen
Minor Planet #3363 Bowen

More references

The Bruce Medalists

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