Tributes to Prof Donald Lynden-Bell, of Cambridge’s Institute of Astronomy, who changed our understanding of the universe
Institute’s founding director dies at 82 - and Lord Martin Rees calls him “one of the greatest astronomers of his generation’
He tackled fundamental questions about the universe – with theories on super-massive black holes and on the formation of our own galaxy.
The astronomical community has paid tribute to Prof Donald Lynden-Bell, the first director of the Institute of Astronomy at the University of Cambridge, following his death at the age of 82.
A former president of the Royal Astronomical Society (1985-87) and winner of the 2008 Kavli Prize for Astrophysics, Prof Lynden-Bell died peacefully at home in Cambridge on February 6.
Lord Martin Rees, the Astronomer Royal and a fellow of Trinity College, worked with him at the Institute of Astronomy for 20 years and recalled “many zany digressions” during their conversations into the scientific puzzles on Prof Lynden-Bell’s mind.
Lord Rees told the Cambridge Independent: “It was a privilege and pleasure to be his colleague. He’s left an enduring scientific legacy – as one of the great astronomers of his generation and, more broadly, through those he mentored, through his influence on UK astronomy, and the friendships he forged around the world.”
Prof Lynden-Bell had a lifetime interest in stellar dynamics – exploring the motion of stars and their formation into clusters and galaxies – and won numerous medals and prizes, including the Gold Medal of the Royal Astronomical Society in 1993.
He was best known for being first to determine that super-massive black holes lurk at the centre of galaxies. This was critical to his theory, published in a 1969 paper in Nature, that explained the extraordinary power emitted by mysterious quasars – distant sources of radio-wave emission of astounding luminosity that had been discovered five years earlier by Maarten Schmidt in California.
Prof Lynden-Bell explained that quasars are powered by gravity, through the accretion of material into the black holes at the core of galaxies. The luminosity of quasars is caused by frictional heating, as gases rotate in discs around these extremely dense zones.
For this, he shared the 2008 Kavli Prize for Astrophysics with Prof Schmidt. The Kavli prize committee said: “Maarten Schmidt and Donald Lynden-Bell’s seminal work dramatically expanded the scale of the observable universe and led to our present view of the violent universe in which massive black holes play a key role.”
Born in Dover on April 5, 1935, Donald was one of two children of Lt Col Lachlan Arthur Lynden-Bell, a Military Cross recipient, and his wife Monica. Educated at Marlborough, he read mathematics and physics at Clare College, Cambridge, before the writings of Arthur Eddington inspired him to pursue a career in astronomy.
He studied for a doctorate under Leon Mestel on stellar and galactic dynamics at Cambridge and was elected to a research fellowship at Clare, before studying at the California Institute of Technology – as British astronomers simply didn’t have access to world-class optical telescopes at that stage.
He met Ruth Truscott, who was studying chemistry at Cambridge, at the university’s Natural Sciences Club. They married in 1962 and Ruth – who went on to become an eminent chemist and fellow of the Royal Society of Chemistry – also went to Caltech for a year.
It was there in the same year that Prof Lynden-Bell published research with Olin Eggen and Allan Sandage that proposed that the Milky Way probably originated through the dynamic collapse of a single large gas cloud 10 billion years ago. Evolved and debated ever since, this ‘ELS model’ – named after the researchers’ surnames – has been referred to as the “granddaddy of galactic-formation models”.
From 1965, he taught mathematics back in Cambridge, but found it left too little time for research, and he moved after three years to the Royal Greenwich Observatory, where he published work on quasars and black holes.
In 1971 he suggested, with Martin Rees, that the Milky Way had a super-massive black hole at its centre. The theory, published in in a paper titled ‘On quasars, dust and the galactic centre’, was confirmed within years by observations.
In 1972, he was appointed professor of astrophysics at Cambridge and became the founding director of the Institute of Astronomy in Madingley Road, formed from the amalgamation of three institutions – the Cambridge University Observatory established in 1823, the Solar Physics Observatory (1912) and the Institute of Theoretical Astronomy (1967).
He proposed in 1987 – as part of a group of astronomers nicknamed the ‘Seven Samurai’ – the existence of a ‘Great Attractor’, a giant and diffuse region of material about 250 million light-years away that results in the observed motion of our local galaxies towards an area of space in the constellation Centaurus.
In 1994, he and an international team of astronomers announced that they had discovered a galaxy of about 300 billion stars close to our own, which was named Dwingeloo 1 after the radio telescope in the Netherlands that detected it.
He was appointed CBE in 2000 and retired from the Institute of Astronomy a year later, having left a legacy that also included its many spring bulbs, not to mention a reputation for impish humour.
In 2015, Prof Lynden-Bell appeared in a documentary film called Star Men, which followed him and fellow British astrophysicists Roger Griffin, Nick Woolf and Wal Sargent as they retraced a road trip taken half a century earlier across the American South West.
He is survived by his wife, their son and daughter.
A statement from the Institute of Astronomy read: “We shall all miss his intellectual brilliance, which was combined with an interest in everything we do, as well as his positive enthusiasm for life and astronomy.”