Sir Frank Watson Dyson

Sir Frank Watson Dyson , 1868-1939, English astronomer, b. Ashby-de-la-Zouch, grad. Cambridge. He was astronomer royal of Scotland (1905-10) and of England (from 1910). As director (1910-33) of Greenwich Observatory he greatly expanded its research activities and inaugurated (1928) the wireless transmission of Greenwich time. Noted for his study of solar eclipses, he was an authority on the spectrum of the corona and on the chromosphere; his observations of an eclipse (in Brazil, 1919) confirmed Einstein's theory of the effect of gravity on light. Dyson plotted the motions of many previously uncharted stars. A fellow of the Royal Society from 1901, he was knighted in 1915. His publications include Astronomy: A Handy Manual (1910) and Eclipses of the Sun and Moon (with Richard Woolley, 1937).

Dyson, FrankWatson (1868–1939)Englishastronomer. He became the ninth Astronomer Royal in 1910. His main concern was with the accurate measurement of star positions and proper motions, which revealed the distribution of stars in our part of the Galaxy. From observations at several eclipses he identified elements in the solar chromosphere from lines in its spectrum; this success motivated the Greenwich eclipse expedition of 1919 which confirmed Einstein's prediction that a gravitational field bends starlight. Dyson introduced the broadcasting of radio time signals from Greenwich in the 1920s.