Youtor
Cosmic Distance Ladder Cepheid Variables
>> YOUR LINK HERE: ___ http://youtube.com/watch?v=iyisAjHdhas
An introduction to the class of variable stars known as Cepheid variables and their use as standard candles for measuring cosmic distances. Covers Henrietta Leavitt's discovery of the relationship between period and luminosity and an example of how this was used to measure the distance to the Andromeda galaxy which proved the existence of other galaxies. • Here are the links to Henrietta Leavitt's key papers on Cepheid variables: • http://adsabs.harvard.edu/abs/1908AnH... • http://adsabs.harvard.edu/abs/1912Har... • And a recent paper on V1 in the Andromeda galaxy including graphs of the light curves • http://arxiv.org/abs/1111.0262 • Just click on the pdf link to see the documents • Let us know what you think of these videos by filling out our short survey at http://tinyurl.com/astronomy-pulsar. Thank you!
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