New clues are helping to answer the origin of the hidden ocean of Mimas, Saturn's small moon. The force exerted by the planet may have melted the ice.
This new information could have a major impact on the search for life within the Solar System. The first signs that this small moon could hide an ocean date back to 2022, and its existence was confirmed in February 2024. The hidden ocean should be about 20 to 30 kilometers below the surface and should be 40 to 45 kilometers deep. This means that the ocean occupies about half the volume of Saturn's moon, and it is precisely this characteristic that causes the oscillations detected during its rotation. The researchers led by Alyssa Rose Rhoden are now pointing the finger at the phenomenon known as 'tidal heating,' which also plays a fundamental role, for example, for Jupiter's moons. This phenomenon occurs when a body is distorted or stretched due to changes in the gravitational forces it experiences following an elliptical, therefore very elongated, orbit. The variations cause the moon to heat up by drawing energy from its orbit.