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View Full Version : The Cepheids Aren't Falling



Fraser
2008-Sep-19, 09:20 PM
Cepheid variable stars have been used for years as a way to determine distance to other galaxies. The correlation between their period of variability and absolute luminosity provides a cosmic yardstick to measure distances out to a few tens of millions of light-years. Additionally, Cepheids closer to home are used as tools to [...]

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