Andrew McKellar

Andrew McKellar, born on February 2, 1910, in Vancouver, British Columbia, was a pioneering Canadian astronomer renowned for his groundbreaking work in astrophysics. The son of Scottish immigrants, he was one of six children in the McKellar family. His academic journey began at the University of British Columbia, where he graduated in 1930 with a focus on mathematics and physics. He furthered his studies at the University of California, earning his M.S. in 1932 and a Ph.D. the following year, before embarking on a post-doctoral program at MIT.

In 1935, McKellar joined the Dominion Astrophysical Observatory, where he made significant contributions to the field of molecular spectroscopy. His most notable achievement came in 1940 when he became the first to identify molecular matter in the interstellar medium, specifically the organic cyano radical (CN) and the methylidyne radical (CH). His analysis revealed that the surrounding space was extremely cold, with a temperature of approximately -271 °C, a finding that would later be corroborated by the discovery of cosmic microwave background radiation.

During World War II, McKellar served in the Royal Canadian Navy, contributing to the Directorate of Operational Research. After the war, he held a visiting professorship at the University of Toronto and served as president of both the Astronomical Society of the Pacific and the Royal Astronomical Society of Canada. Despite his early death in 1960 due to lymphoma, McKellar's legacy in the scientific community endures, particularly through his work on the carbon-nitrogen nuclear cycle and the temperature estimation of interstellar gas.

Married to Mary Crouch in 1938, McKellar was a devoted family man, raising two children, Andrew Robert William and Mary Barbara. His prolific career included the authorship of seventy-three scientific publications, solidifying his status as a key figure in the field of astronomy.