The Bruce Medalists


  Portrait Photo 1970, courtesy Prof. Oort
Jan Hendrik Oort
28 April 1900 1942 Bruce Medalist 5 November 1992

Jan Oort began studying stellar dynamics under Jacobus C. Kapteyn at the University of Groningen, where he completed his Ph.D. under Pieter van Rhijn in 1926. While a graduate student he spent two years at Yale University with Frank Schlesinger, after which he worked at the University of Leiden from 1924 until his death. In 1927 Oort confirmed Bertil Lindblad’s hypothesis of galactic rotation by analyzing motions of distant stars. Oort found evidence for differential rotation and founded the mathematical theory of galactic structure. During World War II Oort started Hendrik C. van de Hulst on the successful search for a radio spectral line. Following the war Oort led the Dutch group which built a 25-m radio telescope at Dwingeloo and used the 21-cm line to map hydrogen gas in the Galaxy. They found the large-scale spiral structure, the galactic center, and gas cloud motions. In 1950 Oort proposed the now generally accepted model for the origin of comets. He later showed that light from the Crab Nebula is polarized, confirming Iosif S. Shklovskii’s suggestion of synchrotron radiation. He continued researching the Milky Way and other galaxies and their distribution until shortly before his death at 92. Oort was a leader in European astronomy and played a major role in the rise of the European Southern Observatory and other international organizations.

Presentation of Bruce medal
King, Arthur S., PASP 58, 229-32 (1946).

Other awards
American Astronomical Society, Henry Norris Russell Lectureship, 1951.
Association pour le Développement International de l’Observatoire de Nice, ADION medal, 1978
Astronomische Gesellschaft, Karl Schwarzschild Medal, 1972.
Vetlesen Foundation, Vetlesen Prize, 1966.
Inamori Foundation, Kyoto Prize, 1987.
International Balzan Foundation, Balzan Prize, 1984.
National Radio Astronomy Observatory, Jansky Prize, 1967.
Royal Astronomical Society, Gold medal, 1946.

Some offices held
International Astronomical Union, President, 1958-61; General Secretary, 1935-48.

Biographical materials
Blaauw, Adriaan, Biographical Encyclopedia of Astronomers (Springer, NY, 2007), pp. 853-55.
Chapman, David M.F., “Reflections: Jan Hendrik Oort—- Swirling Galaxies and Clouds of Comets,” JRASC 94, 53-54 (2000).
ESA Space Science, “Comet Pioneer: Jan Hendrik Oort,” 27 February 2004.
Oort, J.H., “Some Notes on My Life as an Astronomer,” Annual Reviews of Astronomy & Astrophysics 19, 1 (1981).
Katgert-Merkelijn, J., University of Leiden, Jan Oort, Astronomer
van de Hulst, H.C., Biographical Memoirs of the Royal Society of London 40, 320-26 (1994). van der Kruit, Pieter C., Jan Hendrik Oort: Master of the Galactic System (Springer, 2019). [About this book] .
van Woerden, Hugo, Willem N. Brouw, and Henk C. van de Hulst, eds., Oort and the Universe: A Sketch of Oort’s Research and Person (D. Reidel, Dordrecht, 1980).

Blaauw, Adriaan, Zenit jaarg, 196-210 (1993).
Blaauw, Adriaan & Maarten Schmidt, PASP 105, 681 (1993).
Blaauw, Adriaan, “Oort im Memoriam,” in Leo Blitz & Peter Teuben, eds., 169th IAU Symposium: Unsolved Problems of the Milky Way, (Kluwer Acad. Publishers, 1996), pp. xv-xvi.
Pecker, J.-C., ”La Vie et l’Oeuvre de Jan Hendrik Oort,” Comptes Rendus de l’Acadèmie des Sciences: La Vie des Science 10, 5, 535-540 (1993).
van de Hulst, H.C., QJRAS 35, 237-42 (1994).
van den Bergh, Sidney, “An Astronomical Life: J.H. Oort (1900-1992),” JRASC 87, 73-76 (1993).
Woltjer, L., J. Astrophys. Astron. 14, 3-5 (1993).
Woltjer, Lodewijk, Physics Today 46, 11, 104-05 (1993).

American Institute of Physics Emilio Segrč Visual Archives.
Friedman, Jon R., Portrait Sketch.
University of Leiden: Jan Oort, Astronomer (many).
University of Leiden Observatory (six photos).
Weisstein, Eric W

Named after him
Minor Planet #1691 Oort
Oort Cloud of comets around the Sun.
Oort Constants of galactic structure
J.H. Oort Building, Leiden University

More references

The Bruce Medalists

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