Astrophysics (Index)About

magma ocean

(presumed to occur early in Earth history and potentially on exoplanets)

A magma ocean, i.e., liquid rock on all or on a significant portion of surface of a planet, is expected on a rocky planet of sufficiently high temperature. Early in Earth's history, they are presumed to have occurred due to energy from accretion, impacts, and/or due to radioactive heating.

As such, in the study of extra-solar planets, they can be inferred from temperature estimates (based on the stellar class and orbital size, and/or information from a light curve near a secondary eclipse), along with the estimates of the density of the planet (from the combination of radial velocity and transit data), if the density estimates suggest a rocky composition. Models of atmosphere formation take into account the presence of magma oceans.

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