Pluto
Dwarf planet Pluto may also harbor a subsurface ocean, according to research published in 2020. Data beamed back by NASA’s New Horizons spacecraft showed an unusually dynamic surface, which scientists have been studying since the probe’s historic 2015 flyby.
Pluto appears to have gotten off to a hot start when it formed, allowing it to support an early subsurface ocean. Over time, as this liquid gradually froze and expanded, Pluto’s crust began to swell and crack. Some liquid water could still exist beneath Pluto’s frozen surface to this very day, in a process similar to the one seen on Ceres.
