Annie Jump Cannon
||This article includes a list of references, but its sources remain unclear because it has insufficient inline citations. (November 2012)|
|Annie Jump Cannon|
Annie Jump Cannon
December 11, 1863|
|Died||April 13, 1941(aged 77)|
|Known for||Stellar classification|
|Notable awards||Henry Draper Medal (1931)|
Annie Jump Cannon (December 11, 1863 – April 13, 1941) was an American astronomer whose cataloging work was instrumental in the development of contemporary stellar classification. With Edward C. Pickering, she is credited with the creation of the Harvard Classification Scheme, which was the first serious attempt to organize and classify stars based on their temperatures.
The daughter of shipbuilder and state senator Wilson Lee Cannon and his second wife, Mary Elizabeth Jump, Cannon grew up in Dover, Delaware. Cannon's mother had a childhood interest in star-gazing, and she passed that interest along to her daughter. She had four older step-siblings from her father's first marriage, as well as two brothers, Robert and Wilson. Cannon never married but was happy to be an aunt to her brother's children.
At Wilmington Conference Academy, Cannon was a promising student, particularly in mathematics. In 1880 Cannon was sent to Wellesley College in Massachusetts, one of the top academic schools for women in the U.S. The cold winter climate in the area led to repeated infections, and in one Cannon was stricken with scarlet fever. As a result, Cannon became almost completely deaf.
She graduated with a degree in physics in 1884 and returned home. Uninterested in the limited career opportunities available to women, she grew bored and restless. Her partial hearing loss made socializing difficult, and she was generally older and better educated than most of the unmarried women in the area. She had made a trip to Europe in 1892 to photograph the solar eclipse, but returned with her situation little improved.
In 1894, however, her mother died. Life in the home grew more difficult, and she finally wrote to her former instructor at Wellesley, Professor of Physics and Astronomy Sarah Frances Whiting, to see if there was a job opening. Whiting hired her as her assistant, which allowed Cannon to take graduate courses at the college. The school had started offering a course in astronomy, which became her true calling. While at Wellesley, Professor Whiting inspired her to learn about spectroscopy. Also during those years, Cannon developed her skills in the new art of photography.
She returned to Wellesley in 1894 for graduate study in physics and astronomy. In order to gain access to a better telescope, she decided to enroll at Radcliffe Women's College at Harvard, which had access to the Harvard College Observatory. In 1896, Edward C. Pickering hired Cannon as his assistant at the Harvard observatory. By 1907 she had received a MA from Wellesley.
Professional history 
In 1896 Cannon became a member of Pickering’s women, the women hired by Harvard Observatory director Edward Charles Pickering to complete the Draper Catalog mapping and defining every star in the sky to photographic magnitude of about 9.
Anna Draper, the widow of Henry Draper, who was a wealthy physician and amateur astronomer, set up a fund to support the work. Pickering made the Henry Draper Catalog a long-term project to obtain the optical spectra of as many stars as possible, and also to index and classify stars by spectra. If making measurements was hard enough, the development of a reasonable classification was at least as difficult.
Not long after the work on the Draper Catalog began, a disagreement developed as to how to classify the stars. Antonia Maury, who was also Henry Draper's niece, insisted on a complex classification system while Williamina Fleming, who was overseeing the project for Pickering,  wanted a much more simple, straightforward approach. Cannon negotiated a compromise. She started by examining the bright southern hemisphere stars. To these stars she applied a third system, a division of stars into the spectral classes O, B, A, F, G, K, M. Her scheme was based on the strength of the Balmer absorption lines. After absorption lines were understood in terms of stellar temperatures her initial classification system was rearranged to avoid having to update star catalogues. The mnemonic of "Oh Be A Fine Girl, Kiss Me" has developed as a way to remember stellar classification.
The female astronomers doing this groundbreaking work at Harvard Observatory earned 25 cents per hour, which was less than what the secretaries at the university earned. 
Cannon’s work was “theory-laced” but simplified. Her observation of stars and stellar spectra was extraordinary. Her Henry Draper Catalogue listed nearly 230,000 stars, all the work of a single observer. Cannon also published other catalogues of variable stars, including 300 that she discovered. Her career lasted more than 40 years, during which time women gained acceptance within the scientific community.
Annie Jump Cannon died April 13, 1941 after receiving a regular Harvard appointment as the William C. Bond Astronomer. She also received the Henry Draper Medal, which only one other female has won, Martha P. Haynes (who shared it with a male colleague).
Awards and honors 
- In 1925 received the first honorary doctorate Oxford University ever awarded to a woman.
- In 1929 the National League of Women Voters listed her as one of the 12 "greatest living American women".
- In 1931 awarded the Henry Draper Medal from the National Academy of Sciences.
- In 1932 awarded the Ellen Richards Prize.
- First woman elected an officer of the American Astronomical Society.
- In 1938 named the William Cranch Bond Astronomer at Harvard.
- The lunar crater Cannon is named after her.
- She was nicknamed "Census Taker of the Sky" for classifying 230,000 stellar bodies, more than any other person, male or female.
- The Annie Jump Cannon Award in Astronomy is named in her honor. It has been awarded annually to a woman astronomer in North America since 1934.
- Cannon Hall, a residence dormitory at the University of Delaware is named in her honor.
- Reynolds, Moira Davison (2004). American Women Scientists: 23 Inspiring Biographies, 1900-2000. McFarland. p. 18. ISBN 978-0-7864-2161-9.
- Shteynberg, Catherine (8 May 2009). "Pickering's Women". Smithsonian Institution Archives.
- "Star classification". Astrophysical.org.
- Johnson, George (2005). Miss Leavitt's Stars. W. W. Norton & Company, Incorporated. ISBN 0-393-32856-2.
- "Henry Draper Medal". National Academy of Sciences. Retrieved 19 February 2011.
Further reading 
- Greenstein, George (1993). "The Ladies of Observatory Hill". American Scholar 62: 437–446.
- Nancy J. Veglahn, Women Scientists, 1991 in literature, Facts on File, ISBN 0-8160-2482-0
- Wellesley College Astronomy Department: Annie Jump Cannon
- Bibliography from the Astronomical Society of the Pacific
- Annie Jump Cannon Audio Talk with Colleagues