Answer:
My Dear Friend
It's seen storms being generated in Saturn's clouds, it's recognized that Saturn's blue haze fades a bit in the hemisphere receiving less sunlight. It's identified about 8 new moons (Probably more, now...) and has measured the mass & density of it's moons. Some of them are very light - for their size, some appear to be composed of just empty space.
It solved the riddle of Japetus - for almost 300 years, astronomers have seen that it's 8 to 10 times more reflective on one side than the other - and, it's due to dark, sun-melted material collecting on it's leading edge, while bright ice crystals remain on the trailing side.
It was Voyager that first spotted the hexagon-shaped structure at Saturn's poles, but it was Cassini that sent us detailed photos of it - and, it's thought to be due to Saturn's rapid rotation coupled with the winds in it's atmosphere.
Cassini also flew through the water geysers of Encelaudus, and detected simple amino acids in the spray; and radar-mapped Titan, detecting flat areas that are thought to be liquid methane and ethane lakes - the first body besides Earth with liquid on the surface.
I hope this answer helps you