Astronomer cecilia payne-gaposchkin (1900-1979)

Cecilia Payne was a British-born American astronomer and astrophysicist. She was the first to discover that stars were composed primarily of hydrogen and helium. When her mother refused to fund her college education, she applied for and received a scholarship at Cambridge College. Even though Cecilia completed her studies at Cambridge, she was refused a degree because she was a woman.

Cecilia decided to leave England for the United States to accept a graduate fellowship from Harlow Shapley, the new director of the Harvard College Observatory. At the time, Harvard was renowned for its comprehensive study of the stellar spectrum. Cecilia earned her Ph.D. (~1925) in astronomy from Radcliffe College. Her thesis involved measuring the absorption lines in stellar spectra and was described by Russian-American astronomer Otto Strauve as “the most brilliant Ph.D. thesis ever written in astronomy.”

“She showed that the wide variation in stellar spectra is due mainly to the different ionization states of the atoms and hence different surface temperatures of the stars, not to different amounts of the elements. She calculated the relative amounts of eighteen elements and showed that the compositions were nearly the same among the different kinds of stars. She discovered, surprisingly, that the Sun and the other stars are composed almost entirely of hydrogen and helium, the two lightest elements. All the heavier elements, like those making up the bulk of the Earth, account for less than two percent of the mass of the stars.” - Steven Soter and Neil deGrasse Tyson

Later, she converted her thesis into a book titled “Stellar Atmospheres.”

In 1934 she married the Russian astronomer Sergei Gaposchkin. Their professional collaboration contributed widely to the physical understanding of the chemical elements in the stars.

Although it took until 1956, Cecilia Payne became the first woman to be promoted to full professor from within Harvard,

Cecilia Helena Payne-Gaposchkin was a British–American astronomer associated with the Women Astronomical Computers, a group of female astronomers and analysts at Harvard College Observatory (HCO). She discovered the chemical composition of stars and, in particular, that hydrogen and helium are the most abundant elements in stars. From star spectra, she determined stellar temperatures and chemical abundances using the thermal ionization equations of Meghnad Saha. Her work was of fundamental importance in the development of the field of stellar atmospheres, and her observations and analyses of variable stars laid the foundation for their use as indicators of galactic structure.

Read on for stories about Cecilia's life, work process, and contributions to science!

Archival Resources

See here for Oral history interviews from four women astronomers at the Harvard College Observatory, including Payne-Gaposchkin.

A Search of “Cecilia Payne-Gaposchkin” in Hollis for Archival Discovery:

Papers of Cecilia Helena Payne-Gaposchkin, 1924, circa 1950s-1990s, 2000

COLLECTION Identifier: HUGB P182.XX

“Cecilia Helena Payne-Gaposchkin (1900-1979), Phillips Professor of Astronomy at Harvard University (1956-1966) was a pioneer in astrophysics and a leading authority on variable stars.”

Papers of Margaret Harwood, 1902-1974

COLLECTION Identifier: 79-M62--2007-M228

Correspondence, family papers, photographs, etc., of Margaret Harwood, astronomer.

Correspondence: Gaposchkin, Cecilia Payne

ITEM — Carton: 2 Identifier: 79-M62--2007-M228, 50.

Correspondence between Harwood and Payne-Gaposchkin. 

Papers of Dorrit Hoffleit, 1906-2005

COLLECTION Identifier: MC 529

Papers of Dorrit Hoffleit, astronomer at Harvard and Yale Universities and at the Maria Mitchell Observatory in Nantucket.

Payne-Gaposchkin, Cecilia H.: articles and correspondence, 1961-1996 (scattered)

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British and American astronomer (1900–1979)

Cecilia Payne-Gaposchkin (born Cecilia Helena Payne; (1900-05-10)May 10, 1900 – (1979-12-07)December 7, 1979) was a British and American astronomer and astrophysicist. In her 1925 doctoral thesis she proposed that stars were composed primarily of hydrogen and helium.

Her groundbreaking conclusion was initially rejected by leading astrophysicists, including Henry Norris Russell, because it contradicted the science of the time, which held that no significant elemental differences distinguished the Sun and Earth. Independent observations eventually proved that she was correct.

Overcoming barriers for female scientists – Payne did not receive a degree from Cambridge despite completing her studies – her work on the cosmic

Cecilia Payne-Gaposchkin (1900 - 1979)

Having met Harlow Shapely of Harvard College observatory, she left England for the US to persue a graduate program in astronomy. Payne was the second student, after Adelaide Ames, to join a fellowship program at the Observatory to encourage women to study there. She became the first person to earn a PhD in astronomy from Radcliffe for her thesis "Stellar Atmospheres, A Contribution to the Observational Study of High Temperature in the Reversing Layers of Stars". Astronomer Otto Struve characterized it as "undoubtedly the most brilliant Ph.D. thesis ever written in astronomy". Her work allowed her to relate the spectal classes of stars into actual temperatures. She also showed that the variation in stellar absorption lines was due to differing amounts of ionization that occurred at different temperatures, and not due to the different abundances of elements. She also correctly suggested that silicon, carbon, and other common metals seen in the Sun were found in about the same relative amounts as on Earth but the helium and particularly hydrogen were vastly more abundant, by about a factor of one million in the case of hydrogen, concluding that hydrogen was the main constituent of stars. However, she is not fully credited with the discovery because her male superiors convinced her to retract her findings on stellar hydrogen and publish a far less definitive statement. By the time she was aw