An introduction to exoplanets
An introduction to exoplanets

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3  Wobbling stars

Because stars are so much bigger and brighter than planets, they are much easier to study. Astronomers work with light, and the most successful methods used to find planets rely on astronomers doing clever analysis of starlight. 51 Peg b was found by clues in the light astronomers collected from its host star, 51 Peg. The light revealed that the star ‘wobbles’ because it has a planet orbiting around it. The wobbles are far too small to see directly but they can be inferred. Let’s see how this works.

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