A hidden ocean on Titan

The Cassini has shown that Titan, a satellite of Saturn, experiences significant tidal effects on its surface. In the course of its orbit, which lasts 16 days, changes shape: the closer is the gas giant tends to of a rugby ball while closer to a sphere at the farthest point from Saturn. This variation leads to a redistribution of mass and a change in the gravitational field. This is what Cassini measured, thanks to whose data has been concluded that in order to explain the tides experienced, Titan must have a liquid ocean, probably water under the surface.

Artist's vision the possible internal structure of Titan, one of the satellites of Saturn. Includes an underground ocean under an ice layer, as deduced from the data from the Cassini spacecraft.