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Astronomy

Cepheid Variables as Distance Indicators

Quick fact

The American astronomer Henrietta Swan Leavitt discovered in 1908 that Cepheid variables' pulsation periods are directly linked to their intrinsic brightness, allowing astronomers to turn these stars into cosmic yardsticks for measuring distances to far-off galaxies.

Why this is interesting

You’ve probably seen a star twinkle, but imagine a star that swells and brightens, shrinks and dims, all in a reliable rhythm. What if that rhythm could tell you how far away the star is — even if it lies in another galaxy?

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Cepheid Variables as Distance Indicators

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