Frank Watson Dyson

For the English rugby league footballer, seeFrank Dyson.

Sir Frank Dyson KBEFRSFRSE
Born	(1868-01-08)8 January 1868 Measham,Leicestershire, England
Died	(1939-05-25)25 May 1939 (aged 71) At sea
Alma mater	Trinity College, Cambridge
Known for	Astronomer Royal
Awards	Royal Medal(1921)
Signature

Sir Frank Watson Dyson,KBE,FRS,FRSE(8 January 1868 – 25 May 1939) was an Englishastronomerand the ninthAstronomer Royalwho is remembered today largely for introducing time signals ( "pips" ) from Greenwich, England, and for the role he played in proving Einstein's theory ofgeneral relativity.

Biography

Dyson was born inMeasham,nearAshby-de-la-Zouch,Leicestershire, the son of the Rev Watson Dyson, a Baptist minister, and his wife, Frances Dodwell.The family lived on St John Street inWirksworthwhile Frank was one- to three-years-old.They moved toYorkshirein his youth. There he attendedHeath Grammar School,Halifax,and subsequently won scholarships toBradford Grammar SchoolandTrinity College, Cambridge,where he studied mathematics and astronomy, being placedSecond Wranglerin 1889.

Dyson, fourth from the left, rides in an automobile; possibly during the Fifth Conference of the International Union for Co-operation in Solar Research, held inBonn,Germany, 1913

In 1894 he joined theRoyal Astronomical Society,theBritish Astronomical Associationand was given the post of Senior Assistant at Greenwich Observatory and worked on theAstrographic Catalogue,which was published in 1905.He was appointedAstronomer Royal for Scotlandfrom 1905 to 1910, and Astronomer Royal (andDirector of the Royal Greenwich Observatory) from 1910 to 1933. In 1928, he introduced in the Observatory a newfree-pendulum clock,the most accurate clock available at that time and organised the regular wireless transmission from the GPO wireless station at Rugby ofGreenwich Mean Time.He also, in 1924, introduced the distribution of the "six pips"via the BBC. He was for several years President of theBritish Horological Instituteand was awarded their gold medal in 1928.

Dyson was noted for his study ofsolar eclipsesand was an authority on thespectrumof thecoronaand on the chromosphere. He is credited with organising expeditions to observe the 1919 solar eclipse atBrazilandPríncipe,which he somewhat optimistically began preparing for prior to theArmistice of 11 November 1918.Dyson presented his observations of thesolar eclipse of May 29, 1919to a joint meeting of theRoyal Societyand Royal Astronomical Society on 6 November 1919. The observations confirmedAlbert Einstein's theory of the effect of gravity on light which until that time had been received with some scepticism by the scientific community.

Dyson died on board a ship while travelling from Australia to England in 1939, and was buried at sea.

Honours and awards

• Fellow of the Royal Society– 1901

• 

  Dyson at the Fourth Conference International Union for Cooperation in Solar Research atMount Wilson Observatory,1910

  Fellow of theRoyal Society of Edinburgh– 1906
• President,Royal Astronomical Society– 1911–1913
• Vice-president, Royal Society – 1913–1915
• Knighted – 1915
• President, British Astronomical Association, 1916–1918
• Royal Medal of theRoyal Society– 1921
• Bruce Medalof 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 ablue plaque.
• The craterDysonon theMoonis named after him, as is theasteroid1241 Dysona.

Eclipse photograph from1919 expedition

Family

In 1894 he married Caroline Bisset Best (d.1937), the daughter of Palemon Best, with whom he had two sons and six daughters.

Frank Dyson and Freeman Dyson

Although Frank Dyson and theoretical physicistFreeman Dysonwere not known to be related, their fathers Rev Watson Dyson andGeorge Dysonboth hailed fromWest Yorkshirewhere the surname originates and is most densely clustered.Freeman Dyson credited 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 ofjuveniliaentitled "Sir Phillip Robert's Erolunar Collision" – Sir Philip being a thinly disguised version of Sir Frank.

In popular media

ActorAlec McCowenwas cast as Sir Frank Dyson in the TV series,Longitudein 2000.

Selected writings

• Astronomy,Frank Dyson, London, Dent, 1910

See also

• Einstein and Eddington

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: PASP34(1922) 2
• Awarding of RAS gold medal: MNRAS85(1925) 672
• Astronomische Nachrichten268(1939) 395/396(one line)
• Monthly Notices of the Royal Astronomical Society100(1940) 238
• The Observatory62(1939) 179
• Publications of the Astronomical Society of the Pacific51(1939) 336