The Lake County Astronomical Society

Astronomy Bio...Frank Dyson

Jay Bitterman

Frank Watson Dyson was born on January 8, 1868 in Ashby-de-la-Zouch, Leicestershire. He went to Trinity College and graduated from Cambridge in 1889. In 1891 he became a Fellow of Trinity and in 1894 he became chief assistant at the Greenwich Observatory. In 1906 he left to become Astronomer Royal for Scotland and in 1910 returned to Greenwich to serve as Astronomer Royal for England. His early research focussed on problems with gravity theory. He collaborated with William Thackeray at the Greenwich Observatory on a lengthy study of stellar proper motion. In 1906 he published a book on the spectrum of the solar chromosphere based on spectra he had obtained while on several expeditions to study total eclipses of the Sun.

Dyson was among a number of astronomers that confirmed the observations of Jacobus Kapteyn on the proper motions of stars. They suggested that the stars in our galaxy seemed to be moving in two great streams; this was later realized to be the first evidence for the rotation of our Galaxy.

The important function of the Greenwich Observatory was the measurement of time, and Dyson was extremely interested in this aspect of his work. In 1924, Dyson initiated the public broadcasting of the familiar six-pip radio signal by the British Broadcasting Corporation.

Another important area of research at the Greenwich Observatory was the study of solar eclipses, and Dyson played an important part in the organization of the observational expeditions. In 1919 he coordinated the two most significant of these expeditions for that years eclipse. On this occasion, Arthur Eddington confirmed the gravitational deflection of light by the Sun as predicted by Einstein's General Theory of Relativity.

Dyson also made important contributions to the study of the Sun's corona and of stellar parallaxes. He was a talented astronomer and a skilled administrator. In 1933 he retired but continued to be active in research and writing. Dyson authored many research publications and several general books on astronomy. On May 25, 1939, while on a sea voyage from Australia to the coast of South Africa he died.