Donald
Lynden-Bell

Donald Lynden-Bell (1935-2018) studied astronomy at the University of Cambridge in the UK, to which, after periods at the California Institute of Technology and the Royal Greenwich Observatory, he returned in 1972 to become Professor of Astrophysics and the first Director of the Institute of Astronomy.

He was best known in the field for work on the motion of stars, the formation of the galaxy, spiral structures and chemical evolution of galaxies, and the distributions and motions of galaxies and quasars. His 1962 paper, published with Olin Eggen and Allan Sandage, argued that our galaxy originated from the collapse of a single large gas cloud and stimulated huge interest and further research in the area. In 1969, Lynden-Bell proposed that quasars are able to generate the vast quantities of energy that make them visible thousands of millions of light years away thanks to the presence of black holes at their centers. He argued their extreme luminosity arose from frictional heating in a gaseous disk rotating around the black holes.

He was a senior member of a group of astronomers known as the Seven Samurai, which has investigated the motions of nearby galaxies, and which postulated the existence of the Great Attractor - a huge, diffuse region of material around 250 million light years away with a mass equivalent to tens of thousands of Milky Ways, which causes the observed motion of our local galaxies.

Lynden-Bell, a fellow of the UK’s Royal Society, served as the President of the Royal Astronomical Society from 1985-87. He has also worked with his wife Ruth, a chemist, on the thermodynamic equilibrium in clusters of stars and galaxies.