Liquid water discovered on Saturn's moon

The Cassini probe, sent to the moons of Saturn back in 1997, recorded the wobble of the axis of Mimas before deorbiting in 2017. After analyzing this libration, scientists from the Southwestern Research Institute in Colorado suggestedThe case for an ocean-bearing Mimas from tidal heating analysisthat this satellite has a subglacial ocean.

Researchers assume that the water under the ice remains liquid due to tidal deformations. They, in turn, arise under the influence of Saturn's gravity.

The planet is much larger and more massive than the satellite. Diameter Mimasa - about 400 km, and weight - 3.7⋅10¹⁹ kg, y Saturn - about 116 thousand people km and 5.7⋅10²⁶ kg respectively.

Saturn creates a powerful attraction, as a result, the surface of the satellite is periodically deformed. But in such a scenario, the bumps on Mimas, including the huge Herschel impact crater that makes it look like the Death Star, would have to smooth out.

The scientists simulated how Saturn's interior warps under Saturn's gravity to understand how this affects its ice-covered surface. They came to the conclusion that both craters and liquid water on Saturn's moon can exist simultaneously if the thickness of its ice shell is 20–32 km.

At the same time, enough thermal energy remains inside the satellite to keep the salt water under the ice in a liquid state. But large relief irregularities remain noticeable, and no cracks form in the ice shell.

If scientists find new evidence for the existence of liquid water on Mimas, this could lead to the emergence of a new class of space objects. They will not have outward signs of oceans, such as cracks in the surface. But by libration (axis oscillation) and other astronomical data, it will be possible to judge the internal geological activity.