In The Saturn Rings, the New Sculpting Has Been Revealed By Nasa's Cassini

As NASA’s Cassini dove close to Saturn in its final year, the spacecraft gave complex detail on the workings of Saturn’s complex rings, new analysis shows.

Although the mission ended in 2017, science continues to flow from the data collected. A new paper published June 13 in Science describes results from four Cassini instruments taking their closest-ever observations of the main rings.

Findings include fine details of features sculpted by masses embedded within the rings. Textures and patterns, from clumpy to strawlike, pop out of the images, raising questions about the interactions that shaped them. New maps reveal how colors, chemistry and temperature change across the rings.

Like a planet under construction inside a disk of protoplanetary material, tiny moons rooted in Saturn’s rings (named A through G, in order of their discovery) interact with the particles around them. In that way, the paper provides further evidence that the rings are a window into the astrophysical disk processes that shape our solar system.

The observations also deepen scientists’ understanding of the complex Saturn system. Scientists conclude that at the outer edge of the main rings, a series of similar impact-generated streaks in the F ring have the same length and orientation, showing that they were likely caused by a flock of impactors that all struck the ring at the same time. This shows that the ring is shaped by streams of material that orbit Saturn itself rather than, for instance, by cometary debris (moving around the Sun) that happens to crash into the rings.

“These new details of how the moons are sculpting the rings in various ways provide a window into solar system formation, where you also have disks evolving under the influence of masses set within them,” said lead author and Cassini scientist Matt Tiscareno of the SETI Institute in Mountain View, California.