British astrophysicist who studied the motions, equilibrium, luminosity, and atomic structure of the stars. In 1919 his observation of stars during a solar eclipse confirmed Albert Einstein's prediction that light is bent when passing near the Sun, in accordance with the general theory of relativity. In The Expanding Universe 1933 Eddington expressed the theory that in the spherical universe the outer galaxies or spiral nebulae are receding from one another.
Eddington discovered the fundamental role of radiation pressure in the maintenance of stellar equilibrium, explained the method by which the energy of a star moves from its interior to its exterior, and in 1924 showed that the luminosity of a star depends almost exclusively on its mass - a discovery that caused a complete revision of contemporary ideas on stellar evolution.
Eddington was born in Kendal, Cumbria, and studied at Cambridge. Working for the Royal Observatory, Greenwich, London, he was sent to Malta 1909 to determine the longitude of the geodetic station there, and in 1912 he went to Brazil as the leader of an eclipse expedition. In 1913, Eddington returned to Cambridge as professor, and was director of the university's observatory from 1914.
Eddington became a leading exponent of Einstein's relativity theory, and from 1930 he worked on relating the theory of relativity and quantum theory.
Eddington's first book, Stellar Movements and the Structure of the Universe 1914, introduced the subject of stellar dynamics. The Internal Construction of the Stars 1926 became one of the classics of astronomy.