Martin Schwarzschild (May 31, 1912 – April 10, 1997) was a

German-American German Americans (german: Deutschamerikaner, ) are Americans who have full or partial German ancestry. With an estimated size of approximately 43 million in 2019, German Americans are the largest of the self-reported ancestry groups by the Unite ...

astrophysicist.

Biography

Schwarzschild was born in

Potsdam Potsdam () is the capital and, with around 183,000 inhabitants, largest city of the German state of Brandenburg. It is part of the Berlin/Brandenburg Metropolitan Region. Potsdam sits on the River Havel, a tributary of the Elbe, downstream of ...

into a distinguished German Jewish academic family. His father was the physicist

Karl Schwarzschild Karl Schwarzschild (; 9 October 1873 – 11 May 1916) was a German physicist and astronomer. Schwarzschild provided the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-r ...

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 Göttingen (, , ; nds, Chöttingen) is a university city in Lower Saxony, central Germany, the capital of the eponymous district. The River Leine runs through it. At the end of 2019, the population was 118,911. General information The ori ...

in 1916. Schwarzschild studied at the

University of Göttingen The University of Göttingen, officially the Georg August University of Göttingen, (german: Georg-August-Universität Göttingen, known informally as Georgia Augusta) is a public research university in the city of Göttingen, Germany. Founded ...

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 The Legion of Merit (LOM) is a military award of the United States Armed Forces that is given for exceptionally meritorious conduct in the performance of outstanding services and achievements. The decoration is issued to members of the eight u ...

and the

Bronze Star The Bronze Star Medal (BSM) is a United States Armed Forces decoration awarded to members of the United States Armed Forces for either heroic achievement, heroic service, meritorious achievement, or meritorious service in a combat zone. W ...

for his wartime service. After returning to the US, he married fellow astronomer Barbara Cherry. In 1947, Martin Schwarzschild joined his lifelong friend,

Lyman Spitzer Lyman Spitzer Jr. (June 26, 1914 – March 31, 1997) was an American theoretical physicist, astronomer and mountaineer. As a scientist, he carried out research into star formation, plasma physics, and in 1946, conceived the idea of telesco ...

at Princeton University. Spitzer died 10 days before Schwarzschild. Schwarzschild's work in the fields of

stellar structure Stellar structure models describe the internal structure of a star in detail and make predictions about the luminosity, the color and the future evolution of the star. Different classes and ages of stars have different internal structures, reflec ...

and

stellar evolution Stellar evolution is the process by which a star changes over the course of time. Depending on the mass of the star, its lifetime can range from a few million years for the most massive to trillions of years for the least massive, which is cons ...

led to improved understanding of pulsating stars, differential solar rotation, post-main sequence

evolutionary track In astronomy, the main sequence is a continuous and distinctive band of stars that appears on plots of stellar color versus brightness. These color-magnitude plots are known as Hertzsprung–Russell diagrams after their co-developers, Ejnar Hert ...

s on the Hertzsprung-Russell diagram (including how stars become red giants), hydrogen shell sources, the

helium flash A helium flash is a very brief thermal runaway nuclear fusion of large quantities of helium into carbon through the triple-alpha process in the core of low mass stars (between 0.8 solar masses () and 2.0 ) during their red giant phase (the S ...

, and the ages of

star cluster Star clusters are large groups of stars. Two main types of star clusters can be distinguished: globular clusters are tight groups of ten thousand to millions of old stars which are gravitationally bound, while open clusters are more loosely cl ...

s. With

Fred Hoyle Sir Fred Hoyle FRS (24 June 1915 – 20 August 2001) was an English astronomer who formulated the theory of stellar nucleosynthesis and was one of the authors of the influential B2FH paper. He also held controversial stances on other sci ...

, 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 The asymptotic giant branch (AGB) is a region of the Hertzsprung–Russell diagram populated by evolved cool luminous stars. This is a period of stellar evolution undertaken by all low- to intermediate-mass stars (about 0.5 to 8 solar masses) lat ...

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 he headed the

Stratoscope The Stratoscopes were two balloon-borne astronomical telescopes which flew from the 1950s to the 1970s and observed in the optical and infrared regions of the spectrum. Both were controlled remotely from the ground. Stratoscope I possessed a 12-i ...

projects, which took instrumented balloons to unprecedented heights. The first Stratoscope produced high resolution images of

solar granule A granule is a convection cell in the Sun's photosphere. They are caused by convection currents of plasma in the Sun's convective zone, directly below the photosphere. The grainy appearance of the solar photosphere is produced by the tops of ...

s and

sunspot Sunspots are phenomena on the Sun's photosphere that appear as temporary spots that are darker than the surrounding areas. They are regions of reduced surface temperature caused by concentrations of magnetic flux that inhibit convection. S ...

s, confirming the existence of convection in the solar atmosphere, and the second obtained infrared spectra of planets,

red giant A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses ()) in a late phase of stellar evolution. The outer atmosphere is inflated and tenuous, making the radius large and the surface temperature around o ...

stars, and the nuclei of galaxies. In his later years he made significant contributions toward understanding the dynamics of elliptical galaxies. Schwarzschild was renowned as a teacher and held major leadership positions in several scientific societies. 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 Princeton University is a private research university in Princeton, New Jersey. Founded in 1746 in Elizabeth as the College of New Jersey, Princeton is the fourth-oldest institution of higher education in the United States and one of the ...

, where he spent most of his professional life.

Honors

Awards

Karl Schwarzschild Medal The Karl Schwarzschild Medal, named after the astrophysicist Karl Schwarzschild, is an award presented by the Astronomische Gesellschaft (German Astronomical Society) to eminent astronomers and astrophysicists. Recipients SourceGerman Astronomica ...

(1959) * Henry Norris Russell Lectureship (1960) *

Henry Draper Medal The Henry Draper Medal is awarded every 4 years by the United States National Academy of Sciences "for investigations in astronomical physics". Named after Henry Draper, the medal is awarded with a gift of USD $15,000. The medal was established ...

of the

National Academy of Sciences The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the Nat ...

(1960) *

Eddington Medal The Eddington Medal is awarded by the Royal Astronomical Society for investigations of outstanding merit in theoretical astrophysics. It is named after Sir Arthur Eddington. First awarded in 1953, the frequency of the prize has varied over the year ...

(1963) *

Bruce Medal The Catherine Wolfe Bruce Gold Medal is awarded every year by the Astronomical Society of the Pacific for outstanding lifetime contributions to astronomy. It is named after Catherine Wolfe Bruce, an American patroness of astronomy, and was fi ...

(1965) * Rittenhouse Medal (1966) *

Gold Medal of the Royal Astronomical Society The Gold Medal of the Royal Astronomical Society is the highest award given by the Royal Astronomical Society (RAS). The RAS Council have "complete freedom as to the grounds on which it is awarded" and it can be awarded for any reason. Past awar ...

(1969) * Brouwer Award (1992) *

Balzan Prize The International Balzan Prize Foundation awards four annual monetary prizes to people or organizations who have made outstanding achievements in the fields of humanities, natural sciences, culture, as well as for endeavours for peace and the br ...

(1994, with

) *

National Medal of Science The National Medal of Science is an honor bestowed by the President of the United States to individuals in science and engineering who have made important contributions to the advancement of knowledge in the fields of behavioral and social scienc ...

(1997)

Memberships

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...

(1954) * United States

(1956) *

American Philosophical Society The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communit ...

(1981)

Named after him

Asteroid An asteroid is a minor planet of the inner Solar System. Sizes and shapes of asteroids vary significantly, ranging from 1-meter rocks to a dwarf planet almost 1000 km in diameter; they are rocky, metallic or icy bodies with no atmosphere. ...

4463 Marschwarzschild

References

External links

*Published papers of Martin Schwarzschild o
SAO/NASA Astrophysics Data System
*D. Merritt
Martin Schwarzschild's Contributions to Galaxy Dynamics

Oral history interview with Martin Schwarzschild, 4 sessions, 1977
Niels Bohr Library,

American Institute of Physics The American Institute of Physics (AIP) promotes science and the profession of physics, publishes physics journals, and produces publications for scientific and engineering societies. The AIP is made up of various member societies. Its corpora ...

, College Park, MD.
Oral history interview with Martin Schwarzschild, 1986

Charles Babbage Institute The IT History Society (ITHS) is an organization that supports the history and scholarship of information technology by encouraging, fostering, and facilitating archival and historical research. Formerly known as the Charles Babbage Foundation, ...

, University of Minnesota, Minneapolis. {{DEFAULTSORT:Schwarzschild, Martin 1912 births 1997 deaths 20th-century American astronomers American astrophysicists Foreign Members of the Royal Society Members of the United States National Academy of Sciences German astrophysicists 20th-century German physicists Jewish emigrants from Nazi Germany to the United States Jewish American scientists Jewish physicists National Medal of Science laureates Scientists from Potsdam Recipients of the Gold Medal of the Royal Astronomical Society Recipients of the Legion of Merit 20th-century American Jews Members of the American Philosophical Society