It has been 12 long years; that’s 4,380 days for you & me, or in Saturn terms, not even a year has passed. (It takes Saturn 10,832 Earth days to complete one orbit around the Sun so one year on Saturn is really 29.7 years here on Earth.)
The Cassini spacecraft has accomplished tons in that space of time now it’s time for a final mission. After a death defying series of moves of close fly-bys of the rings and then actually inserting itself in between the rings that will provide the rare opportunity of directly sampling the ring material, then Cassini will pass Saturn’s swirling cloud tops, but then next September is when it get really exciting. Next September Cassini will dive through Saturn’s clouds, recording all the while, and disintegrate much like a meteor. Why are the scientists doing this? Besides the cool data to be obtained, this is to make sure that Casini when it runs out of fuel doesn’t just bounce around like a pinball and contaminate Titan or Enceladus – two worlds of particular interest. The Saturn system is of tremendous interest to us. From the resources throughout the entire system to the awesome architecture one could design on a world such as Titan (while its atmosphere is thick, its gravity is lower than that of the Moon.) Titan with its climate which includes winds and rain, has dunes and rivers, lakes, and seas although its liquid oceans, rivers, and lakes are likely Methane and Ethane. Another Earth-like feature, Titan has seasons.
But back to Cassini.
Cassini has accomplished much in its ten years - from 1) the Huygens probe landing on Titan,
2) the discovery of active and icy plumes on the Moon Enceladus. (Geysers, possibly a sub-surface ocean),
3) the rings of Saturn which were found to be a genuine laboratory for teaching us how planets form,
4) recent data from the radio & plasma wave instrumentation have shown that the changes in radio waves is not tied to the interior rotation of Saturn as thought and that the planet's rotation is different in the northern and southern hemispheres,
5) we got to study prebiotic chemistry on Titan (Definition is existing or occurring before the origin of life. In this case having beginning with sunlight and methane, ever more complex molecules form until they become large enough to form the smog that covers the giant moon.)
6) We got to study the great storm of 2010-2011(A storm that grew so big as to encircle the planet with a swirling band. It had the largest temperature increases ever recorded for any plane. Molecules never before seen in Saturn’s upper atmosphere were detected. The storm diminished shortly after its head collided with its tail, a little less than a year after it began.)
7) We saw vertical structures in Saturn’s rings,
8) the mystery of the frozen wastelands of lapetus were solved. (OK, I’ll explain: Dark, reddish dust in Iapetus's orbital path is swept up and lands on the leading face of the moon. The dark areas absorb energy and become warmer, while uncontaminated areas remain cooler. The moon’s long rotation period contributes to the yin-yang effect.)
9) We obtained our first ever complete view of the north polar hexagon and discovery of giant hurricanes at both of Saturn’s poles. And so much more.
Back to Cassini’s suicidal plunge; the pictures from these close flybys should be spectacular. It would be quite a view riding along with Cassini as it approaches the broad expanse of the rings from above, watching them disappear for an instant as you see them edge on, then get a completely different view from the undersides with the sun shining through the icy particles making all kinds of rainbow effects.