Titan is Hiding a Global OceanScientists have discovered that the most interesting moon of Saturn, Titan, is hiding a global ocean 100km underneath its surface.
Possible scenario for the internal structure of Titan
The evidence comes courtesy of Cassini, which has flown past Titan more than 80 times. We've already observed plenty of strange behavior on the moon--it rains and snows there, for example, and has an atmosphere denser than our own, giving it the honor of the only moon with an appreciable atmosphere--so it shouldn't be surprising that a thorough analysis of the moon would reveal further weirdness.
By getting so close to the moon so often, scientists can closely observe how Titan orbits Saturn, how it spins, how strong its gravitational pull is and the topography of the surface. Essentially, what the team did is look for tides. See, as Titan spins around Saturn in an elliptical orbit. That orbit means that the gravitational pull is greater at some points than others. The research team used this data to look for tidal flexing, which is the stretching and pulling of a moon due to a core that isn't non-dense core. The less dense, the more the rock flexes.
Using data from 6 flybys, Cassini was able to determine that Titan has an underground sea of liquid water. Which is remarkable considering how cold it is way out there in space. Other moons have water ice; very few are thought to have it in liquid form.
Scientists hope that the water can explain how Titan's atmosphere is made up largely of gaseous methane, despite the fact that it is quickly destroyed.
Said team member Jonathan Lunnine,
"The presence of a liquid water layer in Titan is important because we want to understand how methane is stored in Titan's interior and how it may outgas to the surface. This is important because everything that is unique about Titan derives from the presence of abundant methane, yet the methane in the atmosphere is unstable, and will be destroyed on geologically short timescales."