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Astronomy

Determining Stellar Masses and Radii from Binary Star Eclipses

Quick fact

By precisely timing the eclipses of a binary star system and measuring the tiny dimming of light, astronomers can determine the stars' radii to within a few percent and their masses to similar precision—without ever seeing the stars as more than point sources of light.

Why this is interesting

Imagine two stars dancing so close that they periodically block each other's light from our view. What if we could measure their masses and sizes just by watching that cosmic wink?

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Determining Stellar Masses and Radii from Binary Star Eclipses

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