It is impossible to imagine Saturn without its rings, but it appears that the planet didn’t always have them. More than that, it is very likely that the rings formed a lot later than the planet. Gravity science data from NASA’s Cassini spacecraft definitely seems to indicate that.
According to the research that analyzed the data, experts believe that the rings formed around 10 million to 100 million ago. To put things into perspective, this would mean that the rings formed around the time dinosaurs still roamed on Earth.
The Cassini mission
Cassini managed to accomplish its mission admirably. In order to collect all the needed data, the spacecraft had to get closer. However, it was also running out of fuel. Despite this, Cassini managed to dive between the rings and the planet 22 times.
“Only by getting so close to Saturn in Cassini’s final orbits were we able to gather the measurements to make the new discoveries,” said Cassini radio science team member and lead author Luciano Iess, of Sapienza University of Rome. “And with this work, Cassini fulfills a fundamental goal of its mission: not only to determine the mass of the rings, but to use the information to refine models and determine the age of the rings.”
The age of the rings is not the only thing that was discovered. Scientists also observed that the planet has layers, and the outer ones rotate faster than the inner ones and the core.
“The discovery of deeply rotating layers is a surprising revelation about the internal structure of the planet,” said Cassini Project Scientist Linda Spilker of JPL. “The questions are what causes the more rapidly rotating part of the atmosphere to go so deep, and what does that tell us about Saturn’s interior?”