| Citation | Martin Schwarzschild is one of the outstanding astrophysicists of this era. His researches have been distinguished by a a broad and imaginative creativity, supported by a keen physical insight and an insistence on precision in detail. He has published important papers in both observtion and theory, opening up new avenues of research that have developed into major subdisciplines of astrophysical inquiry. He is probably best known for his work on stellar structure and evolution, a central field of astronomy in which his contributions have been seminal. He was the first to capitalize on the power of the electronic digital computer for research in this area, developing imaginative techniques which are now standard. His work with Fred Hoyle explained the giant star phenomenon, with extended hydrogen envelopes around helium cores, as a natural consequence of stellar evolution. His systematic researches uncovered other important events in a stellar lifetime, such as shell flashes, and he redicovered "semi-convection" independently of its original discoverer Roger Tayler. His 1968 book has been a standard text for a generation of students entering this field. More recently he has been largely responsible for opening up the area of the dynamical equilibrium of galaxies. His emphasis on the importance of triaxial systems, and his skilled use of the computer for the construction of stellar orbits for such systems, and for the final use of these orbits for synthesizing self-consistent models for elliptical galaxies have changed our conception of these systems and led to much activity by others, with a variety of conferences and symposia on this topic now taking place. In observational astronomy he pioneered the use of space telescopes for precise imaging of the Sun, planets and stellar systems. His Stratoscope I, a 12-inch diameter solar telescope lifted to 80,000 feet altitude by balloon, was the first instrument to obtain sharp photographs above most of the earth's fluctuating atmosphere, and gave fascinating new information on dynamical processes in the solar atmosphere. His subsequent Stratoscope II, with a 36-inch diameter mirror, gave a similar first-of-a-kind results on the outer planets and galactic nuclei. This work blazed a trail for other diffraction-limited instruments, including the Hubble Space Telescope, which is now revolutionizing optical astronomy. The breadth of his interests is shown by his early observational research (with the Mt. Wilson 100-inch telescope) on variable stars, by one of the first theoretical papers on plasma instabilities, and by a theory for the heating of the solar corona. In a pioneering paper with Barbara Schwarzschild, he found differences in chemical composition between high- and low-velocity dwarf stars, crucial to our understanding of the chemical evolution of galaxies; and before the 21cm radio line measurements, he showed that optical measurements of the Andromeda galxy pointed towards the now omnipresent flat rotation curve. His versatility, combined with a tremendous enthusiasm for ideas and unusual skills in communicating has made him a very effective advisor on scientific matters, both national and international, and he has been particularly active in promoting international cooperation. Altogether, his election would be greeted with applause both at home and abroad. |