COUNCIL CHRONICLE – On Monday, October 16, mission team members revealed fresh findings from Cassini’s Grand Finale or, more exactly, its death dive.
NASA’s Cassini spacecraft was active for almost two decades in space with 13 of those years being spent orbiting Saturn and studying its planetary system. However, a little over a month ago, the spacecraft took one last daring dive between the rings of the gas giant. September 15 marked Cassini’s last day as, upon coming into contact with the planet’s upper atmosphere, it burned up.
Cassini’s Death Dive Reveals Fresh Findings about Saturn’s Rings and Moonlets
On October 16, the Cassini mission team revealed a series of new findings based on the data gathered by the spacecraft. Although scientists still have a lot more information to process, they believe to be closer to discovering some of the secrets behind Saturn’s rings.
Namely, research indicates that the planet’s rings may be held together with some help from the many moons of Saturn. Also, new moonlets may have the opposite effect, as they might be creating gaps in the rings.
Currently, observations detected 62 moons around Saturn, some of them having been noted to orbit within the gaps between its rings. However, those “holes” are also the home of several moonlets, which are smaller space bodies, no more than 500 meters in diameter.
Albeit small, the moonlets are still very efficient at clearing out space for themselves. This process was noted to be similar to the action of new and forming planets which clear out space for themselves in the dust rings around a star.
These ring features, caused by the moonlets, have been named propellers. Now, the Cassini team revealed its surprise at finding such elements in the last image of Saturn’s rings ever taken by Cassini.
Also, the team has a new theory as to why Saturn’s rings aren’t spreading out and dissipating into space. Namely, they believe that the B ring (Saturn’s third) is being kept in place by the gravity of Mimas. Also, the outer edges of the A ring are being controlled by Janus’s gravitational pull. Both Mimas and Janus are among Saturn’s more known moons.
As it is, Cassini’s death dive is expected to come with even more new data and answers, but very likely some further questions as well.
“There are whole careers to be forged in the analysis of data from Cassini,” states Linda Spilker, the Cassini project scientist at the NASA Jet Propulsion Laboratory. “In a sense, the work has only just begun.”
— CassiniSaturn (@CassiniSaturn) October 16, 2017
Image Source: NASA/JPL