Cassini spacecraft’s last observation of Saturn’s rings

Twenty-one months have passed since NASA's Cassini-Huygens spacecraft to study Saturn and its system made its fateful plunge into Saturn’s atmosphere on September 15, 2017. During its last several months, the spacecraft focused on observing Saturn’s trademark rings.

The results of the Cassini spacecraft’s final and closest observation of Saturn’s rings and the movements of its satellites were published on journal Science on Thursday (local time). The study revealed the detailed structure and the surface of Saturn.

The results verified that the materials rotating around Saturn were affecting the ring. There is a thin and dark furrow called “Keeler Gap” almost at the outer edge of the bright and outermost A ring. Daphnis, a small moon which is 8 kilometers in diameter, plows through the empty space. Cassini’s observation shows in detail that Daphnis sweeps components of the ring, causing them to undulate towards the outer edge.

The final observation also performed close measurements of the sizes and traits of propellers. It has also been revealed that Saturn’s rings that seem sleek when seen from afar are actually uneven and have combed patterns, which were created as the ring’s particles are more densely lumped or elongated depending on their sizes or traits.


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