ANNIE JUMP CANNON Born: Dover, Delaware, December 11, 1863 Died: Cambridge, Massachusetts, April 13, 1941
ANNIE JUMP CANNON • ELDEST DAUGHTER TO WILSON CANNON, SHIPBUILDER AND DELAWARE STATE SENATOR, AND HIS SECOND WIFE, MARY JUMP • MOTHER FUELED HER INTEREST IN ASTRONOMY BY TEACHING HER THE CONSTELLATIONS
EXTENSIVE EDUCATIONAL BACKGROUND • graduated from Wellesley College in 1884. • became a "special student" of astronomy at Radcliffe College in 1894 • received an M.A. from Wellesley College in 1907 • received an honorary doctorate from the University of Delaware in 1918 • was the first woman to receive a doctor of astronomy degree from Groningen University, in 1921. • was the first woman to receive an honorary degree from Oxford in 1925 • received an honorary doctorate from Wellesley College in 1925 • received an honorary doctorate from Oglethorpe University in 1935 • received an honorary doctorate from Mount Holyoke College in 1937 <http://www.wellesley.edu/Astronomy/annie/education.html>
CAREER ASTRONOMER THEORIST OF STAR SPECTRA
CAREER • “In 1896 Annie Jump Cannon was hired by Professor Edward Charles Pickering, director of the Harvard College Observatory to catalogue variable stars and classify the spectra of southern [hemisphere] stars.” • “Pickering conceived the Henry Draper Memorial as a long-term project to obtain optical spectra of as many stars as possible and to index and classify stars by their spectra.” <http://www.wellesley.edu/Astronomy/annie/education.html>
ACCOMPLISHMENTS • She devised the "arbitrary" division of stars into the spectral classes O, B, A, F, G, K, M. (mnemonically recognized as Oh Be AFine Girl Kiss Me) • It was far simpler than existing divisions. Her Draper Catalogues ultimately listed over 400,000 stars
ACCOMPLISHMENTS • Cannon also published catalogs of variable stars (including 300 she discovered). • One notable variable star that Cannon discovered is the dwarf nova, SS Cygni which repeated its outburst cycle about every 60 days.
ADDITIONAL INFORMATION ABOUT CANNON’S WORK • The Variable Star– “Variable stars are stars that change brightness. The brightness changes of these stars can range from a thousandth of a magnitude to as much as twenty magnitudes over periods of a fraction of a second to years, depending on the type of variable star.” <http://www.aavso.org/vstar/>
ADDITIONAL INFORMATION ABOUT CANNON’S WORK TYPES OF VARIABLE STARS EXTRINSIC– “variability is due to the eclipse of one star by another or the effects of stellar rotation.” INTRINSIC– “variation is due to physical changes in the star or stellar system.” <http://www.aavso.org/vstar/types.shtml>
ADDITIONAL INFORMATION ABOUT CANNON’S WORK • EXTRINSIC VARIABLES INCLUDE; ECLIPSING BINARY AND ROTATING VARIABLES • INTRINSIC VARIABLES INCLUDE; ERUPTIVE [CATACLYSMIC] AND PULSATING VARIABLES
ADDITIONAL INFORMATION ABOUT CANNON’S WORK • Research on variable stars is important because it provides information about stellar properties, such as mass, radius, luminosity, temperature, internal and external structure, composition, and evolution. • Stellar Spectroscopy uses the absorption lines of stellar emissions/radiations to classify stars.
OBAFGKM • There are new spectral types that expand on the OBAFGKM template, cataloging some rare spectral types. • Here are a few mnemonics fromhttp://www.geocities.com/SummerDale33/Mnemonic.html O B A F G K M L T : • Officially, Bill Always Felt Guilty Kissing Monica Lewinsky Tenderly O B A F G K M : • Only Boys Accepting Feminism Get Kissed Meaningfully
WORKS CITED • http://www.sdsc.edu/ScienceWomen/cannon.html • http://scienceworld.wolfram.com/astronomy/topics/Stars.html • http://www.wellesley.edu/Astronomy/annie/education.html • http://www.aavso.org/vstar/ • http://www.geocities.com/SummerDale33/Mnemonic.html