Europa's Hidden Ocean Could Surpass Earth's Seas, Fueled by Jupiter's Tidal Rhythm
Europa, though smaller than Earth’s Moon, may hide a global ocean tens to about 150 km deep beneath an ice shell and could contain more liquid water than all Earth's oceans; the ocean remains liquid due to tidal heating from Jupiter, amplified by the Io–Europa–Ganymede Laplace resonance, plus radiogenic heat and an insulating ice shell. Evidence comes from magnetic induction data and surface geology, and NASA’s Europa Clipper (launched 2024) will fly by 49 times to measure ice thickness, ocean depth, salinity, and possible chemical gradients to assess habitability.