The rings of Saturn could have fashioned a lot later than the planet itself, in accordance with a brand new evaluation of gravity science information from NASA’s Cassini spacecraft.
The findings, led by scientists from Rome’s Sapienza College, point out that Saturn’s rings fashioned between 10 million and 100 million years in the past. From our planet’s perspective, meaning Saturn’s rings could have fashioned in the course of the age of dinosaurs.
Saturn fashioned 4.5 billion years in the past, within the early years of our photo voltaic system. There have been clues that its ring system is a younger upstart that hooked up to Saturn years afterward. However how lengthy afterward?
To determine the age of the rings, scientists wanted to measure the mass of the rings, or how a lot materials they maintain.
Researchers had the remote-sensing measurements from Cassini and each of NASA’s Voyager spacecraft within the early 1980s. Then got here Cassini’s unprecedented, up-close information from its closing orbits in 2017. Because the spacecraft was working out of gasoline, it carried out 22 dives between the planet and the rings.
The dives allowed the spacecraft to behave as a probe, falling into Saturn’s gravity area, the place it might really feel the tug of the planet and the rings.
Radio alerts despatched to Cassini from the antennas of NASA’s Deep Area Community and the European Area Company relayed the spacecraft’s velocity and acceleration.
As soon as scientists knew how a lot gravity was pulling on Cassini, inflicting it to speed up – all the way down to a fraction of a millimeter per second – they might decide how huge the planet is and the way huge the rings are.
“Solely by getting so near Saturn in Cassini’s closing orbits have been we in a position to collect the measurements to make the brand new discoveries,” mentioned Cassini radio science workforce member and lead creator Luciano Iess, of Sapienza College of Rome.
“And with this work, Cassini fulfills a elementary purpose of its mission: not solely to find out the mass of the rings, however to make use of the data to refine fashions and decide the age of the rings.”
The findings have been revealed within the journal Science.
The brand new proof of younger rings lends credence to theories that they fashioned from a comet that wandered too shut and was torn aside by Saturn’s gravity — or by an occasion that broke up an earlier era of icy moons.