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Cepheid variable |
Also found in: Wikipedia, Hutchinson | 0.01 sec. |
Cepheid variableOne of a class of variable stars whose period of variation is closely related to its luminosity and is therefore useful in measuring the distances to clusters of stars and galaxies. Named for the prototype of this class found in the constellation Cepheus, classical Cepheids have periods from about 1.5 days to over 50 days and are Population I stars (see Populations I and II). The longer the period of such a star, the greater its natural brightness; this relationship was discovered in 1912 by the American astronomer Henrietta Leavitt (b. 1868—d. 1921). How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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| Feast of the University of Cape Town in South Africa reexamined the period-luminosity relationship for Cepheids, using Hipparcos to measure the distances to 26 of the nearest such stars. |
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