Albrecht Unsöld

Albrecht Otto Johannes Unsöld ( born April 20, 1905 in Bolheim (Württemberg ), † 23 September 1995) was a German astrophysicist with prägendem impact on the physics of stellar atmospheres.

Life and work

Unsöld was the son of a pastor and studied physics in Tübingen and Munich, where Arnold Sommerfeld Theoretical Physics, and especially quantum mechanics taught. There he completed his doctoral dissertation in 1927 contributions to quantum mechanics of atoms. After living in Potsdam, Munich, Hamburg Pasadena and he was in 1932 Professor and Director of the Institute for Theoretical Physics at the University of Kiel. 1958/59 he was its rector. In 1973 he became Professor Emeritus.

Early Unsöld began to apply quantum- physical methods to the study of stellar atmospheres. He won the first detailed analyzes of stellar atmospheres and their abundances and described formation and broadening of lines in the spectra of the sun and other stars. Unsölds analysis of the spectrum of the B0 star Tau Scorpii, taken in 1939 during a visit to the Yerkes and McDonald observatories, provided the first detailed analysis of a star other than the sun. Unsöld and his Kiel School developed basic principles of determining the physical conditions in stellar atmospheres.

In addition to his influential work on the physics of stellar atmospheres and the standard textbook of astronomy, the new cosmos, he published the magazine for Astrophysics, until it merged with other European magazines in the Astronomy and Astrophysics.

Awards

Works (selection)

• Physics of stellar atmospheres, with particular reference to the sun. Springer, Berlin, 1938.
• The new cosmos. Springer, Berlin 1967.
• Evolution of cosmic, biological and mental structures. Scientific Publishing Company, Stuttgart 1981.