Joseph Algernon Pearce

Joseph Algernon Pearce

Joseph Algernon Pearce, astrophysicist (b at Brantford, Ont 7 Feb 1893; d at Victoria, BC 8 Sept 1988). Together with J.S. PLASKETT, the first director of the Dominion Astrophysical Observatory in Victoria, BC, Pearce published the first detailed spectroscopic analysis of the structure of our Milky Way Galaxy in 1935. Using radial velocities of the very luminous hot stars visible from Victoria, they demonstrated that the sun is two-thirds out from the centre of our galaxy and rotates in 220 million years. Pearce studied radial velocities of O- and B-type stars, catalogued the observable B stars and found that 40% are double stars, and estimated the temperatures and dimensions of representative giant eclipsing double stars. Director of the Dominion Astrophysical Observatory 1940-51, Pearce was active in the International Astronomical Union, the Royal Astronomical Society of Canada (president, 1940) and the American Astronomical Society (vice-president, 1944-46). Elected a fellow of the Royal Society of Canada in 1931, he was president in 1949. Pearce was a major in the Canadian forces in WWI, and also a Freemason and an enthusiastic philatelist. Shortly before his death, Minor Planet no. 3304 was named Pearce in his honour.