Schwarzschild was born in
Potsdam into a distinguished German Jewish academic family. His father was the physicist
Karl Schwarzschild and his uncle the astrophysicist
Robert Emden. His sister,
Agathe Thornton, became a classics scholar in New Zealand. In line with a request in his father's will, his family moved to
Göttingen in 1916. Schwarzschild studied at the
University of Göttingen and took his doctoral examination in December 1936. He left Germany in 1936 for Norway and then the United States. Schwarzschild served in the US army intelligence. He was awarded the
Legion of Merit and the
Bronze Star for his wartime service. After returning to the US, he married fellow astronomer Barbara Cherry (1914–2008). In 1947, Martin Schwarzschild joined his lifelong friend,
Lyman Spitzer at Princeton University. Spitzer died 10 days before Schwarzschild. Schwarzschild's work in the fields of
stellar structure and
stellar evolution led to improved understanding of pulsating stars, differential solar rotation, post-main sequence
evolutionary tracks on the Hertzsprung-Russell diagram (including how stars become red giants), hydrogen shell sources, the
helium flash, and the ages of
star clusters. Schwarzschild was also among the first to use digital computers in the study of astronomy. With
Fred Hoyle, he computed some of the first stellar models to correctly ascend the
red-giant branch by steadily burning hydrogen in a shell around the core. He and Härm were the first to compute stellar models going through thermal pulses on the
asymptotic giant branch and later showed that these models develop convective zones between the helium- and hydrogen-burning shells, which can bring nuclear ashes to the visible surface. Schwarzschild's 1958 book
Structure and Evolution of the Stars taught a generation of astrophysicists how to apply electronic computers to the computation of stellar models. In the 1950s and ’60s, responding to a challenge by fellow professor
James Van Allen, he headed the
Stratoscope projects, launching telescopes into the
stratosphere with high-altitude balloons. This allowed the photography of astronomical phenomena without atmospheric interference. The first Stratoscope produced high resolution images of
solar granules and
sunspots, confirming the existence of convection in the solar atmosphere, and the second obtained infrared spectra of planets,
red giant stars, and the nuclei of galaxies. In his later years he made significant contributions toward understanding the dynamics of elliptical galaxies. In the 1980s, Schwarzschild applied his numerical skills to building models for triaxial galaxies. Schwarzschild was the Eugene Higgins Professor Emeritus of Astronomy at
Princeton University, where he spent most of his professional life. ==Honors==