Birth: December 11, 1863
Death: April 14, 1941
Stellar Classification System
Discovery of 300 Variable Stars
First woman officer in the American Astronomical Society
Image Source: Wikimedia Commons
Cataloging around 400,000 stars, including 300 variable stars she discovered, Annie Jump Cannon was a pioneering astronomer responsible for creating the classification system that was adopted as the universal standard.
She studied physics and astronomy at Wellesley College, graduating in 1884, and spent two years studying astronomy at Radcliffe College. Limited by the opportunities for her in physics and astronomy she branched out into new fields like photography, traveling Europe and having a book of her prose and photographs given away at the Chicago World’s Columbian Exposition of 1893. Working as a junior physics teacher at Wellesley afforded her the chance to study spectroscopy which led her to take classes at Radcliffe to obtain access to Harvard Observatory.
Hired in 1896 as an assistant to the staff at Harvard Observatory she was assigned to catalog bright stars in the southern hemisphere. Finding the current classification systems did not meet her needs, she combined two and created her own, that used the pneumonic “Oh, Be A Fine Girl – Kiss Me!” that became the standard used the world over. She used the strength of the Balmer absorption lines, later understood in terms of stellar temperatures, to structure her system.
Between 1881 and 1924 her work was published in nine volumes of the Henry Draper Catalogue. In 1922 the International Astronomical Union formally adopted Cannon’s classification system and it is still being used today with minor changes.
In honor of her hard work and dedication to astronomy, many accolades have been bestowed upon Cannon, including having a lunar crater and an asteroid named in her honor. Cannon was the first woman to hold an officer position in the American Astronomical Society, which now awards the Annie J. Cannon award to a distinguished female astronomer at the beginning of her career. In reflection of her work she stated, “My success, if you would call it that, lies in the fact that I have kept at my work all these years. It is not genius, or anything like that, it is merely a patience.”
Written by Angela Goad