1782 - John Goodricke[?] notices that the brightness variations of Algol are periodic and proposes that it is partially eclipsed by a body moving around it
1964 - Subrahmanyan Chandrasekhar and Richard Feynman develop a general relativistic theory of stellar pulsations and show that supermassive stars are subject to a general relativistic instability
... 2000 and the 2003 U.S. Department of State website.
External Links
Brasil.gov.br (http://www.brasil.gov.br) - Official governmental portal (in Portuguese)
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