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The Cepheids Aren't Falling - Universe Today
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 investigate how … Continue reading "The Cepheids Aren’t Falling"