Bethe, Hans Albrecht (1906-2005)

German-born US physicist who in 1938 worked out the details of how nuclear mechanisms power the Sun and other stars. He also worked on the first atom bomb but later became a peace campaigner. He was awarded the Nobel Prize for Physics in 1967 for his theory of nuclear reactions, and discoveries concerning production of energy in stars.

Bethe was born in Strasbourg (now in France), and educated at the universities of Frankfurt and Munich. He left Germany in 1933, moving first to the UK and then, in 1935, to the USA, where he became professor of theoretical physics at Cornell University; his research was interrupted by World War II and by his appointment as head of the theoretical division of the Los Alamos atom-bomb project. He has been a leading voice in emphasizing the social responsibility of the scientist and opposed the US government's Strategic Defense Initiative (Star Wars) programme.