Eddington proposed that hydrogen fusion powers stars; that is, it
powers what are called “main sequence” stars. Bethe
and von Weizsäcker provided the math for the fusion process,
showing that stars release heat according to E = mc2.
Hertzsprung and Russel graphed the brightness and temperature of
stars, showing their normal life-cycles. The eventual states of
some stars is speculative because the age of the observable
universe is shorter than the time it should take for them to reach
Eventually, when a star burns up all its fuel, it becomes a
white or black dwarf, a neutron star, or a black hole; however,
this part of the theory was not completed until the brilliant
Subrahmanyan Chandrasekhar published his doctoral work in 1931.
See also in The book of science:
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