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What evidence suggests that Europa has an ocean below its surface?
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extraterrestrial life
An illustration of the Earth-size planet TOI 700e orbiting within the habitable zone of its star. The habitable zone is the area around a star where liquid water, and thus possibly life, can survive on a planet's surface. Its Earth-size sibling, TOI 700d, can be seen in the distance.
Evidence suggesting that Europa harbors a subsurface ocean includes several key observations:
- Magnetic Field Data: Europa possesses an induced magnetic field that requires the presence of an electrically conducting fluid layer beneath the surface, likely a salty liquid water ocean.12
- Surface Geology: The moonâs surface is exceptionally smooth with very few impact craters, indicating it is geologically young and subject to ongoing resurfacing. High-resolution images show regions where the icy crust has fractured, rotated, and tilted, suggesting the presence of a semifluid layer beneath.12
- Surface Composition: Spectroscopic analysis has identified salt deposits and other compounds on the surface, which may have originated from liquids or plumes erupting from a subsurface reservoir.12
- Tidal Heating: Models suggest that tidal energy generated by Jupiterâs gravity provides sufficient heat to maintain a liquid ocean beneath the icy crust.12
The Europa Clipper mission aims to further investigate these findings to confirm the ocean's existence and assess the moon's potential habitability.3