The Bruce Medalists


  Portrait Photo University of California, Santa Cruz, courtesy AIP Emilio Segrè Visual Archives
Robert Paul Kraft
16 June 1927 2005 Bruce Medalist 26 May 2015

Bob Kraft was was born in Seattle and earned his bachelor’s and master’s degrees at the University of Washington. He taught mathematics and astronomy for two years at Whittier College and then entered the University of California, Berkeley, where he worked for Otto Struve and earned his Ph.D. in 1955 under George Herbig. After short stays at Mt. Wilson Observatory, Indiana University, and Yerkes Observatory, he was on the staff of the Mt. Wilson & Palomar Observatories for seven years. In 1967 he joined the University of California, Santa Cruz as professor and almost immediately became acting director of the Lick Observatory. He served as acting director for a total of five years and later as director from 1981 to 1991. During the last three years of his directorship, he also led the University of California Observatories, which included the University of California’s share of the Keck Observatory. A stellar spectroscopist, he used Cepheid variable stars to measure interstellar absorption and obtain distances to clusters, and he made a definitive study of stellar rotations. He showed that all dwarf novae and ordinary novae are close binary stars, some with orbital periods little more than an hour. As early as 1962 he considered gravitational radiation as the cause of the evolution of a close binary. He worked with many collaborators to determine the chemical composition of different types of evolved stars in the galactic halo and globular clusters in an effort to determine the evolution of baryonic matter in the Galaxy. He was widely respected as both an administrator and a teacher.

Other awards
American Astronomical Society, Helen B. Warner Prize, 1962; Henry Norris Russell Lectureship, 1995.

Some offices held
American Astronomical Society, President, 1974-76.
International Astronomical Union, President, 1997-2000.

Biographical materials
Kraft, Robert P., “Thoughts on Receiving the Bruce Medal,” Mercury 34, 6, 32-34 (Nov/Dec 2005).
Kraft, Robert P., “An Astronomical Life Salted by Pure Chance,” Ann. Revs. Astron. Astrophys. 47, 1-26 (2009).

Santa Cruz Sentinel, 30 May 2015.
Stephens, Tim, University of California, Santa Cruz, 28 May 2015.
Woo, Elaine, Los Angeles Times, 1 June 2015

2005, courtesy of Dr. Kraft
AIP Center for History of Physics (several)

Named after him
Minor Planet #3712 Kraft

More references

The Bruce Medalists

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