Person Seaton; Michael John (1923 - 2007) Seaton Michael John 1923 - 2007 British Male Bristol, Gloucestershire, England 16/01/1923 19230116 29/05/2007 20070529

Physicist Education: His academic career was almost stillborn. Shocked by Chamberlain’s speech on his return from Munich and by the civil war in Spain, he joined the Young Communist League in 1938. He soon found himself in trouble with the police because of his political activities, and expulsion from school followed, but he was fortunately allowed to sit matriculation exams. The war intervened, and he volunteered for air crew and served as a navigator in Bomber Command until 1945. After the war he studied physics at UCL where he took his BSc and his PhD. Career: By 1951 he had published a research paper, which established the density of the gas in interstellar space; this was the the first of his nearly 300 research papers. The controversial conclusions of that first paper were later proved to be correct. During the 1950s, as a lecturer at UCL and during sabbatical leave at the Institut d’Astrophysique in Paris, he laid the foundations of his later work on collisions between electrons and atoms. His first calculations were done on mechanical calculators, but he adopted electronic computers as soon as they became available in the 1960s. In collaboration with observational astronomers, notably Don Osterbrock, of Lick Observatory, California, he applied the results of his calculations to interpreting astronomical spectra, providing powerful new tools for measuring temperatures and densities in distant astronomical objects; these techniques remain in use today. The interplay between theoretical atomic physics and astronomy was to remain a central theme of his work. He was certainly not an amateur stargazer: when challenged one winter evening after a dinner party to locate the Orion nebula – on which he had written a seminal paper – he was unable to identify even the constellation of Orion. Foreseeing the crucial role that digital computers would play in science, he oversaw the procurement by UCL of what was, at the time, the most powerful computer in Europe. He formulated ambitious plans to implement on the new computer the quantum mechanical methods that he and others had developed. Many computer codes written by Seaton and his students and collaborators in the 1960s and 1970s are still in use today. His former students recall with affection Seaton’s eccentricities. During scientific discussions, he would often fall silent for long periods, head inclined and in deep reflection. Those who knew him would simply wait until, reflection over, he would return to life and frequently be able to give the solution to the problem in hand. It was very rare for a student to leave his office without a clear idea of how to advance his research project. In the late 1970s he was drawn further into astronomy when the International Ultraviolet Explorer satellite was launched. From space the spectra of astronomical objects can be measured at ultraviolet wavelengths, which are not transmitted through the Earth’s atmosphere, and a host of discoveries resulted. The project that was to occupy much of his last 25 years – and long into formal retirement – began in 1982, during one of his summer visits to the University of Colorado. It had become apparent that there were deep flaws in the understanding of the transmission of light through the outer atmospheres of stars. New atomic physics calculations were needed, and Seaton assembled a team of two dozen people, many of them former students, in laboratories all around the world. It is a testament to the respect and affection in which he was held that so many were willing to follow his lead in this project. In terms of intellectual power and breadth of scientific knowledge, Seaton had few peers. He continued to publish the results from the project right up to his death; the data produced will form the basis for interpreting the spectra of stars for years to come. President of the Royal Astronomical Society in 1978. Honours: Hughes Medal 1992 Married twice; first to Olive Singleton, who died in 1958. Second to Joy Balchin. A son and daughter from first marriage, a son by the second. Royal Society roles: Council: 1974-1976 Medals and prizes: Hughes Medal 1992 Fellow 16/03/1967 44 References: 'Address of the President, Sir Michael Atiyah, OM, Given at the Anniversary Meeting on 30 November 1992' in NR 1993 vol 47 pp 109-118 Obituary in 'The Times' 7 June 2007 International Standard Archival Authority Record for Corporate Bodies, Persons and Families - ISAAR(CPF) - Ottawa 1996 ISBN 0-9696035-3-3 National Council on Archives, Rules for the Construction of Personal, Place and Corporate Names, 1997 16 Jan 1923 - 29 May 2007 NA355 21/11/2001 Andyg Martind 28/03/2023 RS_NET\JonathanB Yes http://viaf.org/viaf/113439 107883fb-886e-4fc5-86a2-6baef9c5480e