https://www.newscientist.com/article/mg23531430-400-cassinis-grand-finale-the-spacecraft-that-unveiled-saturn/

TITAN’S methane lakes. Icy Enceladus spouting geysers of hot water. Sponge-like Hyperion. Ravioli-shaped Pan and Atlas. Iapetus with its equatorial ridge battered by ancient craters. Close-ups of those iconic rings engirdling the gas-giant planet itself, and gigantic hurricanes around its poles.

The Cassini probe, launched in 1997, has orbited the Saturn system for 13 years. What it has revealed is astounding – and challenges our understanding of planets and their satellites everywhere, says planetary scientist Julien Salmon of the Southwest Research Institute in Boulder, Colorado. “If everything comes from the same processes, should we get so much diversity?” he asks. “It seems like every moon has a part of the story to tell.”