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Mega-Earth

A mega-Earth is a massive terrestrial exoplanet that is at least ten times the mass of Earth. Mega-Earths are substantially more massive than super-Earths (terrestrial and ocean planets with masses around 5–10 Earths). The term "mega-Earth" was first coined in 2014, when Kepler-10c was revealed to be a Neptune-mass planet with a density considerably greater than that of Earth.