Martin Schwarzschild, Higgins Professor of Astronomy, Emeritus, at Princeton University, died on 10 April 1997 following a heart attack, just ten days after the death of his close personal and scientific friend, Lyman Spitzer. They were together at Princeton for half a century; they made Princeton a truly unique place for astrophysics; and they kept it unique for decades. Their presence was strongly felt all the way to the end, and it is very hard to imagine how we shall continue without them. Martin would have been 85 on May 31.
Martin Schwarzschild was awarded posthumously the National Medal of Science by President Clinton. Just a few months earlier, Martin had become a Foreign Member of the Royal Society (London), and I had the privilege of hosting him in my office when, on 18 March, he signed a page of the "Charter Book," brought from London by the Astronomer Royal, Sir Martin Rees. Lyman Spitzer was the fourth person present at this ceremony.
Born in Potsdam, Germany, Martin Schwarzschild received his PhD from the Goettingen University in 1935. He barely knew his father, Karl Schwarzschild, who died in 1916. Karl was a famous scientist, best known for his Schwarzschild metric and the criterion for convective instability. Martin's uncle, Robert Emden, was the author of a fundamental book on the theory of self-gravitating gaseous spheres, the polytropic stellar models. Martin Schwarzschild was associated with Princeton University from 1947 onward and formally retired in 1979. He had previously been at Columbia University (1940-47), at Harvard (1937-1940), and Oslo (1936-37). During World War II, he served as a first lieutenant with the United States Army, after becoming a naturalized American citizen.
Schwarzschild was one of the most prominent astrophysicists of this century. He pioneered the application of modem computers to science and was a leader in the theory of stellar evolution, off-the-ground astronomy, and the dynamics of elliptical galaxies. He was a member of the National Academy of Arts and Sciences, National Academy of Sciences, Royal Society, and many other prestigious organizations. He received numerous awards, among them the Henry Draper Medal of the NAS, the Bruce Medal of the Astronomical Society of the Pacific, the Eddington and Gold Medals of the Royal Astronomical Society, and the Balzan Prize (shared with Sir Fred Hoyle). He was invited to give many honorary lectures, among them the Henry Norris Russell and Gibbs lectures at the AAS and American Mathematical Society, respectively, and the Darwin Lecture at the RAS.
Schwarzschild was Vice President of the International Astronomical Union for two terms (1964-70). As a Vice President and then President of the AAS from 1967 to 1972, he initiated and led an important reorganization of the Society and of the Astrophysical Journal.
Martin Schwarzschild was best known as a theorist. His remarkable book Structure and Evolution of the Stars, published in 1958, became the standard text for many decades. His landmark papers include the determination of the helium content of the sun (1946), an age estimate for globular clusters (1952 with Allan Sandage), the flat rotation curve of galaxies (1954), the large scale application of electronic computers to calculate stellar models (1955 with R. Harm), and the evolution of globular cluster stars up the red giant and supergiant branches (1955, with Hoyle). Upon his retirement, Schwarzschild invigorated a very different field, the dynamical structure of triaxial elliptical galaxies. In a series of fundamental papers, he developed a method of construction of self-consistent models made of a large number of stellar orbits.
While he was best known as a theorist, he made a major step in instrumentation and observations with the Stratoscope I and II programs, balloon-borne 12 inch and 36 inch telescopes respectively. These instruments provided the first images of solar atmospheric turbulence and of the core of M31 not blurred by the Earth's atmosphere. These were major steps in the lead-up to the Hubble Space Telescope.
Martin was not just a great scientist; he understood very well that scientific research is an activity done within a broader framework of a modem society. Let me quote from his address, "When to send your telescope afloat?," delivered on 5 October 1967, upon receiving the Albert A. Michelson award at Case Western University: "At the present time, however, many of us scientists are moving into research undertakings of such physical magnitude that our successes and failures, just as those of the politicians, are becoming accessible to public scrutiny, and since they consume large public funds, they should properly be under such public scrutiny."
Martin Schwarzschild was a wonderful teacher, and many of his students became leaders in various areas of astronomy. He had a remarkable talent for thinking a problem through, understanding what was most essential, and explaining this to any audience. It was a truly amazing experience to attend a colloquium with an average speaker presenting his or her case for a full hour and hear Martin give a one minute summary at the end. That summary seemed to contain more information than the full colloquium, and in many cases it was easier to understand.
With all his remarkable accomplishments, Martin was always a very kind and a very considerate person, providing support and inspiration to all around him, his colleagues as well as his students. He set the tone and the high standards for the thousands of daily lunch conversations at the New South cafeteria on the Princeton campus, and he was the ultimate person to ask for his opinion at weekly lunches at the Institute for Advanced Study, and at weekly seminars. We all feel that with Martin's and Lyman's departures a major era has come to an end.
More extended obituaries of Martin Schwarzschild will appear in the Biographical Memoirs of the NAS and in Publications of the Astronomical Society of the Pacific. Oral history interviews dating from 1975 to 1979 are available at the Center for the History of Physics of the American Institute of Physics. His scientific papers are archived at Princeton University.
Photo (available in PDF version) courtesy Robert Matthews, Princeton Communications Department.