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Astronomy

The Biological Potential of Subsurface Oceans on Icy Moons

Quick fact

Jupiter's moon Europa has a subsurface ocean with more liquid water than all of Earth's oceans combined, and it is kept warm by the gravitational pull of its planet—a process called tidal heating.

Why this is interesting

Imagine an ocean larger than all of Earth's oceans combined, locked beneath a shell of ice and cut off from sunlight. Could life be thriving there, unseen and powered by an energy source we hardly think about?