Thanks to Jack F. for this one:
The spacecraft Cassini was sent to Saturn to gather data about its
moons, specifically Titus and Enceladus. These voyages are groundbreaking because these moons have very active ground systems, some even with tectonic plates. For example, on Titus, there are lakes of what they believe to be methane in the -300 degree temperature. Possibly one of the most ground breaking achievements was the finding of great jets of ice on the southern pole of Enceladus. The
temperature is a lot warmer there, and they believe there might be
liquid water beneath the surface. This and the fact that there is organic material on the southern pole could mean that life could possibly be supported there. Which would be a tremendous breakthrough for mankind.