The Bruce Medalists


  Photo ©Royal Astronomical Society, courtesy Peter Hingley
Harold Spencer Jones
29 March 1890 1949 Bruce Medalist 3 November 1960

Educated at the University of Cambridge, Harold Spencer Jones was successively astronomical assistant at the Royal Observatory, Greenwich, His Majesty’'s Astronomer at the Cape of Good Hope, and, from 1933 to 1955, director of the Royal Observatory and Astronomer Royal. His work was devoted to fundamental positional astronomy. At the Cape he worked on proper motions and parallaxes and the publication of catalogues. Later he showed that small residuals in the apparent motions of the planets are due to the irregular rotation of the earth. He led the worldwide effort to determine the distance to the sun by triangulating the distance of the asteroid Eros when it passed near the earth in 1930-31: he photographed Eros more than 1200 times and reduced the data from other observers. He worked on all aspects of timekeeping and showed that the Earth’s rotation period was no longer adequate as a precise clock. After World War II he supervised the move of the Royal Observatory to Herstmonceux, where it was renamed the Royal Greenwich Observatory. Note: Some sources list his surname as Jones. He preferred Spencer Jones.

Presentation of Bruce medal
Bowen, Ira S., PASP 61, 61 (1949).

Other awards
Royal Astronomical Society, Gold medal, 1943, presented by S. Chapman, MNRAS 103, 116-17 (1943).
Royal Society of London, Royal medal, 1943.

Some offices held
International Astronomical Union, President, 1943-48.
Royal Astronomical Society, President, 1937-39.
United Kingdom, Astronomer Royal, 1933-55.

Biographical materials
Anonymous, “Sir Harold Spencer Jones,” Popular Astronomy 53, 503-06 (1945).
Jackson, J., “Sir Harold Spencer Jones, K.B.E.,” Observatory 76, 15-16 (1956) [on his retirement].
Kopal, Zdenek, Dictionary of Scientific Biography 12, 573-74.
Oxbury, H.F., Great Britons: Twentieth-Century Lives (Oxford Univ. Press, Oxford, UK, 1955)
Ronan, Colin A., Their Majesties’ Astronomers (Bodley Head, London, 1967).
Snedegar, Keith, Biographical Encyclopedia of Astronomers, 2nd ed. (Springer, NY, 2014), pp. 2036-38.
Wooley, R.v.d.R., Biographical Memoirs of the Royal Society 7, 136-45 (1961).

Anonymous, Monthly Notes of the Astron. Soc. Southern Africa 19, 146-149 (1960).
Jackson, J., Observatory75, 15-16 (1956).
Sadler, D.H., QJRAS 4, 113-25
Smart, W.M., JRASC 55, 117-19 (1961).

Caltech Archives
Christmas Island postage stamp
Encyclopedia Brittanica

Named after him
Lunar crater Spencer Jones
Martian crater Jones
Minor planet #3282 Spencer Jones
The Spencer Jones Group of Meridian Instruments at Herstmonceux (now closed)

More references

The Bruce Medalists

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