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Astronomy

How Binary Star Systems Help Measure Stellar Masses

Quick fact

About half of all stars in the Milky Way are part of binary or multiple systems, making this mass-measurement technique one of the most widely used in astronomy.

Why this is interesting

Did you know that most stars are not alone but have companions? Binary star systems are nature’s gift to astronomers—they provide a direct way to weigh stars, something that is impossible for isolated stars.