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Planetary Science

Exoplanet

Definition

A planet orbiting a star outside our solar system. Thousands have been found since the first confirmed discovery in 1992, primarily by NASA's Kepler and TESS missions. Exoplanets show a wide variety of sizes, compositions, and orbital configurations.

Related Terms

Habitable Zone

The region around a star where liquid water could exist on a planet's surface, often called the Goldilocks zone. It vari...

Transit Method

A technique for detecting exoplanets by measuring a star's dimming as a planet passes in front. The most successful dete...

Star

A massive, luminous sphere of hot gas held together by gravity, generating energy through nuclear fusion. Stars range fr...

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Surface imagery from Curiosity and Perseverance.

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