The Bruce Medalists


  Photo c. 1975, Royal Danish Academy of Sciences and Letters
Bengt Georg Daniel Strömgren
21 January 1908 1959 Bruce Medalist 4 July 1987

Bengt Strömgren, the son of the director of the Copenhagen University Observatory, had published many research papers—mostly in celestial mechanics— and coauthored one book by the time he received his Ph.D. from the University of Copenhagen at age 21. After working there and at the Yerkes Observatory he succeeded his father at Copenhagen in 1940. He was director of Yerkes and McDonald Observatories from 1951 to 1957 and spent ten years at the Institute for Advanced Study in Princeton before returning to Copenhagen University and the Nordic Institute for Theoretical Physics (NORDITA). Strömgren did important research in stellar structure in the 1930s, but he is best known for his theory of the ionized gas clouds around hot stars. He found relations between the gas density, the luminosity of the star, and the size of the “Strömgren sphere” of ionized hydrogen around it. He surveyed such H II regions in the Galaxy, and he also did important work on stellar atmospheres and ionization in stars. He calculated the relative abundances of the elements in the sun and other stars and worked on optical design and, for many years, on the development of photoelectric photometry.

Presentation of Bruce medal
Mayall, N.U., PASP 71, 79 (1959).

Other awards
American Astronomical Society, Henry Norris Russell Lectureship, 1965.
Association pour le Développement International de Astronomische Gesellschaft, Karl Schwarzschild Medal, 1969.
Royal Astronomical Society, Gold medal, 1962, presented by W.H. McRae, QJRAS 3, 81-83 (1962).

Some offices held
American Astronomical Society, President, 1966-67.
International Astronomical Union, President, 1970-73; General Secretary, 1948-52.

Biographical materials
Cayrel, Roger, “La vie et l’oeuvre de Bengt Strömgren,” Comptes Rendus de l’Académie des Sciences: La Vie des Sciences 6, 609-610 (1989).
Pedersen, Olaf, Bengt Strömgren.
Rebsdorf, Simon Olling, “Bengt Strömgren: Growing Up With Astronomy, 1908–1932,” Journal for the History of Astronomy 34, 171-99 (2003).
Rebsdorf, Simon Olling, The Father, the Son, and the Stars: Bengt Strömgren and the History of Twentieth Century Astronomy in Denmark and in the USA (Ph.D. dissertation, University of Aarhus, 2004; LAP Lambert Acad. Publ., 2010).
Rebsdorf, Simon Olling, “Bengt Strömgren: Interstellar Glow, Helium Content, and Solar Life Supply, 1932–1940,” Centaurus 49, 56-79 (2007).
Rebsdorf, Simon Olling, Bengt Strömgren’s life among the stars, Niels Bohr Institute website.
Strömgren, B., “Scientists I have Known and Some Astronomical Problems I Have Met,” Ann. Rev. Astron. Astrophys. 21, 1-11 (1983).

Spitzer, Lyman, Jr., Physics Today 41, no. 3, 112, 114 (1988).
Rudkjobing, M., QJRAS 29, 282 (1988).
Sky & Telescope 74, 348 (1987).

Library of Congress Prints and Photographs Division. New York World-Telegram and the Sun Newspaper Photograph Collection
Official website of Denmark

Named after him
Minor planet #1846 Bengt
Strömgren Sphere

More references

The Bruce Medalists

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