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AsteriaStar
Astronomer · 1900 CE – 1979 CE

Cecilia Payne-Gaposchkin

History of AstronomyModern Astronomy

Biography

Cecilia Payne-Gaposchkin discovered what stars are made of. Her 1925 doctoral thesis applied new atomic physics to stellar spectra and concluded that the Sun and stars are composed almost entirely of hydrogen and helium — a result so unexpected she was pressured to downplay it, but which proved correct and transformed our understanding of the universe.

Scientific contributions

  • Showed that stars are made overwhelmingly of hydrogen and helium
  • Wrote one of the most brilliant doctoral theses in astronomy (1925)
  • First woman promoted to full professor at Harvard's Faculty of Arts and Sciences

Major discoveries

Knowledge connections

Sources & references

The primary and reference sources this topic draws on.

  • NASANational Aeronautics and Space Administration

    Mission data, planetary science, space telescopes, and public-domain imagery.

    Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.

  • BritannicaEncyclopaedia Britannica

    General reference for the history of astronomy, biographies, and cultural context.