Alexander Dalgarno

Alexander Dalgarno FRS (5 January 1928 – 9 April 2015) was a British physicist who was a Phillips Professor of Astronomy at Harvard University.

Alexander Dalgarno was born in London in 1928, and spent his childhood there. He was educated in mathematics and atomic physics at University College, London. He was an academic at the Queen's University, Belfast where he worked with Sir David Bates. He married Barbara Kane, from whom he was later divorced, and the marriage produced four children. He moved to Harvard in 1967.

He made contributions in theoretical chemistry, scattering theory, atmospheric physics & chemistry and astrophysics.

Known as the "father of molecular astrophysics", Dalgarno was also a physicist at the Smithsonian Astrophysical Observatory and was formerly the editor of the Astrophysical Journal Letters. He received his education at University College, London, earning a Ph.D. in theoretical physics in 1951. From 1951 through 1967, he rose from assistant lecturer to professor at Queen's University, Belfast, and then joined the Harvard department of astronomy in 1967.

He held the positions of acting director of Harvard College Observatory, chairman of the department of astronomy, associate director of the Harvard-Smithsonian Center for Astrophysics and director of the Institute for Theoretical Atomic and Molecular Physics. Dalgarno's research covered three main areas: theoretical atomic and molecular physics, astrophysics and aeronomy (the study of the upper atmosphere). He was the author of more than 600 publications. Sir David Bates wrote in 1988 that "There is no greater figure than Alex in the history of atomic physics and its applications." In the 1950s, he laid the foundations for long-range atomic interaction studies which are of critical importance for today's interest in Bose–Einstein condensates.

Dalgarno was also cited in the Nebula Award winning novel The Quantum Rose by Catherine Asaro, a science-fiction novel based on Asaro's doctoral work while she was a Ph.D student with Dalgarno.

His work was recognized by many awards, including the prize of the International Academy of Quantum Molecular Sciences, the Davisson-Germer Prize of the American Physical Society, the William F. Meggers Award of the Optical Society of America (1986), the Gold Medal of the Royal Astronomical Society (1986) and the Benjamin Franklin Medal in Physics from the Franklin Institute (2013). He was a Fellow of the American Geophysical Union and the American Physical Society and a member of the U.S. National Academy of Sciences. In 1998, Asteroid 6941 was named Asteroid Dalgarno.

He was a Fellow of the Royal Society and a member of the International Academy of Quantum Molecular Science.