a German physicist noted for his discovery of the reactions that supply the energy in stars. After the rise of the Nazis in Germany, Bethe emigrated to England in 1933 where he held teaching positions at the University of Manchester and the University of Bristol. In 1935, Bethe received the position of Assistant Professor at Cornell University. During 1935-1939, Bethe's main achievement in astrophysics was the exclusion of many possible interactions than can happen inside the stars, leaving just two possibilities: the carbon-nitrogen cycle for massive stars and proton-proton reaction that powers fainter stars like the Sun. Bethe was awarded the Nobel Prize for Physics in 1967.