
Rocky planets orbiting stars, often red dwarfs, with Earth-like composition but varied conditions.Terrestrial exoplanets are rocky worlds orbiting stars other than the Sun, with compositions dominated by silicates and metals, similar to Earth's. They range from scorching lava spheres to frigid ice-covered plains, and their conditions depend heavily on their distance from the host star, the star's type, and the planet's own geological activity. The study of these planets is central to understanding planetary formation, the potential for habitability beyond our solar system, and the diversity of planetary systems in the galaxy.
The first confirmed terrestrial exoplanet was discovered in 1992 around a pulsar, and the first around a Sun-like star, 51 Pegasi b, was found in 1995, though it is a hot Jupiter. The first truly rocky exoplanet, Kepler-10b, was confirmed in 2011 by NASA's Kepler mission.
These planets form from the accumulation of solid material in the protoplanetary disk around a young star, typically closer in than the ice line where volatile compounds remain solid. Their internal structure usually consists of a metallic core, a silicate mantle, and a thin crust, but the exact composition and thickness of these layers vary with the planet's mass and formation history. Surface conditions are shaped by stellar radiation, tidal forces, and internal heat, which can drive volcanism, plate tectonics, or a runaway greenhouse effect.
Terrestrial exoplanets are prime targets in the search for biosignatures, as their atmospheres can be analyzed with telescopes like the James Webb Space Telescope to look for gases that might indicate life.
Some terrestrial exoplanets, like the 'super-Earth' 55 Cancri e, may have surfaces covered in oceans of lava due to their extreme proximity to their host stars.






























