The Bruce Medalists


  Photo 1937, Yale University Astronomy Department Archives, courtesy Dr. Dorrit Hoffleit
Frank Schlesinger
11 May 1871 1929 Bruce Medalist 10 July 1943

Born in New York City, Frank Schlesinger earned his B.S. in 1890 at the College of the City of New York and his Ph.D. in 1898 at Columbia University. After three and one-half years measuring variations in latitude in Ukiah, California, he was hired by Yerkes Observatory, where, with the encouragement of director George E. Hale, he pioneered in the use of photographic techniques to determine stellar parallaxes. He soon showed that photographic methods could give more precise results than visual ones, and with less than one hundredth as much time at the telescope. Schlesinger served as director of Allegheny Observatory from 1905 to 1920 and of the Yale University Observatory from 1920 to 1941. He designed instruments and mathematical and numerical techniques to improve parallax measurements. He published ten volumes of zone catalogs, including some 150,000 stars. He compiled positions, magnitudes, proper motions, radial velocities, and other data to produce the first edition and, with Louise Jenkins, the second, of the widely-used Bright Star Catalogues, making Yale a leading institution in astrometry. He also did spectroscopic work, determining orbits of spectroscopic binary stars. He established a second Yale observatory in South Africa and personally supervised its construction. He was an influential leader in the astronomical community and held several offices, including president, in both the American Astronomical Society and the International Astronomical Union.

Presentation of Bruce medal
Moore, J.H., PASP 41, 8-15 (1929).

Other awards
French Academy of Sciences, Valz medal, 1926.
Royal Astronomical Society, Gold medal, 1927, presented by J.H. Jeans, MNRAS 87, 340-47 (1927).

Some offices held
American Astronomical Society, President, 1919-22.
International Astronomical Union, President, 1932-35.

Biographical materials
Brouwer, Dirk, Biographical Memoir of the National Academy of Sciences 24, 105 (1943-46).
Hoffleit, E. Dorrit, Dictionary of Scientific Biography 12, 176-77.
Smith, Horace A., Biographical Encyclopedia of Astronomers (Springer, NY, 2007), pp. 1024-25.
Tenn, Joseph S., “Frank Schlesinger: The Twenty-Fourth Bruce Medalist,” Mercury 23, 3, 26 (1994)
Tenn, Joseph S., “From Ukiah to Yale: Frank Schlesinger and the Measurement of Stellar Positions,” Griffith Observer 80, 1, 2-16 (2016).

Alden, H.L., “Dr. Frank Schlesinger, 1871-1943,” Monthly Notes of the Astronomical Society of South Africa 3, 16-17 (1944).
Barney, Ida, Popular Astronomy 51, 409-12 (1943).
Mitchell, S.A., PASP 55, 209-16 (1943).
Slocum, Frederick, Ap.J. 98, 241-43 (1943).
Spencer Jones, H., MNRAS 104, 94-98 (1944).

AIP Center for History of Physics
NASA Goddard Space Flight Center, photo, 1931 [with W. de Sitter]

Named after him
Lunar crater Schlesinger
Minor Planet #1770 Schlesinger

More references

The Bruce Medalists

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