Andrew McKellar

Andrew McKellar, MBE, FRSC (February 2, 1910 – May 6, 1960) was a Canadian astronomer who first detected the presence of molecular matter in interstellar space, and found the first evidence of the cosmic radiation left over from the Big Bang. He was born in Vancouver, British Columbia, Canada, to Scottish parents, one of six children of John H. and Mary Littleson McKellar. He studied mathematics and physics at the University of British Columbia, graduating in 1930. He began graduate studies at the University of California, being awarded his M.S. in 1932 and a Ph.D. the following year. Applying to the United States National Research Council, he was awarded a post-doctoral study program for two years at MIT. In 1935 he joined the Dominion Astrophysical Observatory, where he performed research into astrophysics. He was married to Mary Crouch (b. June 3, 1911, d. Nov. 30, 2000) in 1938, and the couple bore two children, Andrew Robert William (Bob) (b. March 28, 1945), and Mary Barbara (b. Nov. 1, 1946) (McKellar) Bulman-Fleming. During World War II he served with the Royal Canadian Navy, in the Directorate of Operational Research. In 1940, McKellar made the first detection of molecular matter in the interstellar medium, identifying the spectrum of the organic compounds cyanogen ("CN") and methyne. ("CH"). The following year, his analysis of the spectra of the cyanogen molecules showed that the surrounding space was very cold with a temperature of approximately -271 °C. At the time, the significance of this was not appreciated; the distinguished Canadian chemist and future Nobel Laureate Gerhard Herzberg said that the temperature measurement "...has of course a very restricted meaning". Almost 25 years later Arno Penzias and Robert Woodrow Wilson detected microwave radiation coming from all regions of the sky corresponding to the same temperature of -271 °C found by McKellar, thus revealing its ubiquity and relation to the radiation left over from the Big Bang. McKellar'