Obituary: Michael Seaton

31 August 2007

Professor Mike Seaton, who has died aged 84, was one of the most outstanding atomic physicists and theoretical astrophysicists of his generation.

His association with UCL, as student and teacher, lasted for six decades, and his research influenced a large part of the international scientific community. …

His scientific output is remarkable for its precision and rigour and comprises nearly 300 publications. …

Seaton graduated with a BSc (1948) and a PhD (1951) from UCL. His early research was conducted under the guidance of professors Sir Harrie Massey and Sir David Bates. In 1951 he published his first research paper, in which he gave an estimate of the density of the interstellar gas. Although contested at the time, his finding proved correct and remains valid today.

By then a member of staff at UCL, Seaton embarked on ground-breaking studies of collisions between electrons and atoms. …

Numerical computing was always essential to his work, and he became as expert in programming electronic computers, which first made their appearance in the 1960s, as he had been in using mechanical hand calculators. Indeed, he played a major role in their procurement by UCL, thereby ensuring that state of the art equipment was available to all the staff. …

He became professor of physics at UCL in 1963 and was emeritus from 1988.

He was one of the greatest specialists in the field of atoms in astrophysics of the last century. He gained great satisfaction from the knowledge that the human mind is capable of deducing detailed information on astronomical objects that cannot be subjected to direct experiments. …

The value of his contributions to theoretical atomic physics and astrophysics was widely recognised. He was elected a fellow of the Royal Society in 1967, became president of the Royal Astronomical Society in 1978, and was made doctor honoris causa of the Observatoire de Paris in 1976.

His last major project was one of the most important and demanding. By 1982, serious flaws were suspected in our understanding of the transmission of light through stellar atmospheres, resulting in major discrepancies in stellar mass estimates. Seaton recognised that the atomic data used in the astrophysical models had to be improved. He established a kind of international task force, comprising many of his former research students, and under his expert and determined leadership, an impressive body of new atomic data emerged. …

Seaton was an awe-inspiring scientist. A meeting with him was always an enriching and sometimes puzzling experience. Great attention to his explanations and patience with his mildly eccentric ways were required, but the reward was in proportion to his intellectual powers. He was an example and an inspiration to many generations of PhD students. His legacy is one of scientific rigour, intellectual courage and uncompromising honesty. …

Claude Zeippen, ‘The Guardian’