Annie Jump Cannon

Annie Jump Cannon's mother taught her the constellations from an old astronomy textbook, pointing them out from the attic of the family home in Dover, Delaware, where her father built ships and sat in the state senate. She studied physics at Wellesley under Sarah Frances Whiting and graduated valedictorian in 1884, then spent roughly a decade away from the field before scarlet fever left her almost completely deaf in her early thirties. Rather than retreat, she went back to school, enrolling at Radcliffe in 1894 specifically to get access to Harvard's telescopes. Two years later, Edward Pickering, running the Harvard College Observatory, hired her as one of his assistants, one more woman on a staff of women doing calculation work the observatory would not pay a man to do.

Cannon joined a Harvard staff of women nicknamed the computers, hired at 25 cents an hour to work through photographic plates the men upstairs would not touch. She simplified an existing letter-based scheme into the sequence O, B, A, F, G, K, M, ranking stars by the strength of their hydrogen lines rather than alphabetically, and the system was fast enough that by 1913 she could classify roughly two hundred stars an hour. Over her career she classified some 350,000 stars for the Henry Draper Catalogue, work the International Astronomical Union made the official standard on May 9, 1922. Harvard named her Curator of Astronomical Photographs in 1911 and, near the end of her life, gave her a named title, William C. Bond Astronomer, in 1938, recognition that arrived only after four decades of unpromoted work.

Doing the observatory's most reproduced astronomical work did not buy Cannon equal footing. She and the other computers earned a fraction of a male assistant's wage for tasks that required as much judgment as clerking, and contemporaries who found intelligent, unmarried working women unsettling said so in print, criticizing her cohort for stepping outside a woman's proper place. Cannon never married, worked essentially without institutional rank for four decades, and received her one named Harvard title, William C. Bond Astronomer, in 1938, three years before she died. In 1935 she used her own Henry Draper Medal prize money to establish the Annie J. Cannon Award for women astronomers, a prize that exists precisely because the field she had spent her life in kept its top honors for men.

Cannon died in Cambridge, Massachusetts, on April 13, 1941, having kept classifying stars almost until the month she died. The system she built, O, B, A, F, G, K, M, is still how astronomers sort stars, adjusted only at the edges since 1922. Recognition kept arriving after her death: induction into the National Women's Hall of Fame in 1994, a Google Doodle on her birthday in 2014, a place on Delaware's American Innovation dollar coin in 2019, and a lunar crater and an asteroid carrying her name. The Annie Jump Cannon Award she funded still goes out every year to a woman early in an astronomy career, the need for it as evident now as when she set it up.

Annie Jump Cannon's life against the full span of the corpus.

• Stellar spectral classification system (O, B, A, F, G, K, M) discovery
  Adopted as the international standard by the IAU in 1922 1901
• Henry Draper Catalogue classifications discovery
  Roughly 350,000 stars classified over her career 1918
• Annie J. Cannon Award other
  Endowed by Cannon for women astronomers 1935

• December 11, 1863 aged 0 Born in Dover, Delaware
• 1884 aged ~21 Graduates valedictorian from Wellesley College with a degree in physics
• 1893 aged ~30 Loses most of her hearing to scarlet fever
• 1894 aged ~31 Enrolls at Radcliffe College to gain access to Harvard's telescopes
• 1896 aged ~33 Hired by Edward Pickering at the Harvard College Observatory
• 1911 aged ~48 Named Curator of Astronomical Photographs at Harvard
• May 9, 1922 aged 58 Her O, B, A, F, G, K, M system is adopted as the international standard
• 1931 aged ~68 Becomes the first woman awarded the Henry Draper Medal
• April 13, 1941 aged 77 Dies in Cambridge, Massachusetts

• Maria Mitchell 1818–1889
  First American woman professional astronomer who discovered a comet and taught at Vassar College. predecessor as a pioneering American woman astronomer
• Henrietta Swan Leavitt 1868–1921
  Discovered the Cepheid period-luminosity relation that made measuring cosmic distances possible. fellow Harvard College Observatory computer
• Vera Rubin 1928–2016
  Measured galaxy rotation curves that provided the main observational evidence for dark matter. later astronomer honored in the tradition Cannon helped buil
• Edwin Hubble 1889–1953
  Astronomer whose discovery of expanding galaxies provided the foundation for the Big Bang theory. used Harvard's spectral classification system in his own wor