Frank Watson Dyson

Sir Frank Watson Dyson
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Born	8 January 1868 (1868-01-08) Measham, Leicestershire, England
Died	25 May 1939 (1939-05-26) (aged 71) At sea
Nationality	British
Alma mater	Trinity College, Cambridge
Known for	Astronomer Royal
Notable awards	Royal Medal (1921)
Signature Sir Frank Watson Dyson's signature

Sir Frank Watson Dyson, KBE, FRS (8 January 1868 – 25 May 1939) was an English astronomer and Astronomer Royal who is remembered today largely for introducing time signals ("pips") from Greenwich, England, and for the role he played in proving Einstein's theory of general relativity.

Biography

Dyson was born in Measham, near Ashby-de-la-Zouch, Leicestershire, the son of the Rev Watson Dyson, but soon moved to Yorkshire. There he attended Heath Grammar School, Halifax, and subsequently won scholarships to Bradford Grammar School and Trinity College, Cambridge, where he studied mathematics and astronomy, being placed Second Wrangler in 1889.

In 1894 he was given the post of Senior Assistant at Greenwich Observatory and worked on the Astrographic Catalogue, which was published in 1905.

He was appointed Astronomer Royal for Scotland from 1905 to 1910, and Astronomer Royal (and Director of the Royal Greenwich Observatory) from 1910 to 1933. In 1928, he introduced in the Observatory a new free-pendulum clock, the most accurate clock available at that time and organised the regular wireless transmission from the GPO wireless station at Rugby of Greenwich Mean Time. He also, in 1924, introduced the distribution of the "six pips" via the BBC. He was for several years President of the British Horological Institute and was awarded their Gold Medal in 1928.

Dyson was noted for his study of solar eclipses and was an authority on the spectrum of the corona and on the chromosphere. He is credited with organising expeditions to observe the 1919 solar eclipse at Brazil and Principe, observations from which confirmed Einstein's theory of the effect of gravity on light.

Dyson died while travelling from Australia to England in 1939 and was buried at sea. He had married Caroline Bisset Best, the daughter of Palemon Best, with whom he had two sons and six daughters.

Honours and awards

• Fellow of the Royal Society – 1901
• President, Royal Astronomical Society – 1911–1913
• Vice-president, Royal Society – 1913–1915
• Knighted – 1915
• President, British Astronomical Association, 1916–1918
• Royal Medal of the Royal Society – 1921
• Bruce Medal of the Astronomical Society of the Pacific – 1922
• Gold Medal of the Royal Astronomical Society – 1925
• Knight Commander of the Order of the British Empire – 1926
• Gold medal of British Horological Institute – 1928
• President of the International Astronomical Union – 1928–1932
• Between 1894–1906, Dyson lived at 6 Vanbrugh Hill, Blackheath, London SE3, in a house now marked by a blue plaque.
• The crater Dyson on the Moon is named after him, as is the asteroid 1241 Dysona.

Eclipse photograph from 1919 expedition

Frank Dyson and Freeman Dyson

Frank Dyson and theoretical physicist Freeman Dyson are not related. However, the latter does credit Sir Frank with sparking his interest in astronomy: because they shared the same last name, Sir Frank's achievements were discussed by Freeman Dyson's family when he was a young boy. Inspired, Dyson's first attempt at writing was a 1931 piece of juvenilia entitled "Sir Phillip Robert's Erolunar Collision" – Sir Philip being a thinly disguised version of Sir Frank.

Selected writings

• Astronomy, Frank Dyson, London, Dent, 1910

External links

• Online catalogue of Dyson's working papers (part of the Royal Greenwich Observatory Archives held at Cambridge University Library)
• Bruce Medal page
• Awarding of Bruce Medal: PASP 34 (1922) 2
• Awarding of RAS gold medal: MNRAS 85 (1925) 672
• Astronomische Nachrichten 268 (1939) 395/396 (one line)
• Monthly Notices of the Royal Astronomical Society 100 (1940) 238
• The Observatory 62 (1939) 179
• Publications of the Astronomical Society of the Pacific 51 (1939) 336