NASA’s Cassini spacecraft ended its historic exploration of Saturn in 2017 and, slowly but surely, scientists are learning more about the ringed planet. Data from the 13-year mission helped scientists determine Saturn’s rings are much newer than the planet itself – and they’re disappearing.
In a report published in June, NASA revealed Cassini was able to collect data on the makeup of Saturn’s rings. Scientists studied the masses embedded in the rings and saw a wide variety of textures and patterns, from clumpy to straw-like.
“New maps reveal how colors, chemistry and temperature change across the rings,” NASA’s recent report notes. “Like a planet under construction inside a disk of protoplanetary material, tiny moons embedded in Saturn’s rings (named A through G, in order of their discovery) interact with the particles around them.”
The rings are a window into the astrophysical disk processes that shape our solar system, evidence in the report shows. Composed of gas and dust, those disks can help form new planets.
In December, new NASA research confirmed Saturn’s rings were being pulled into the planet by gravity. Saturn’s magnetic field was pulling in a dusty rain of ice particles from the rings, also known as “ring rain.”
“We estimate that this ‘ring rain’ drains an amount of water products that could fill an Olympic-sized swimming pool from Saturn’s rings in half an hour,” NASA’s James O’Donoghue, said in a 2018 report.
“From this alone, the entire ring system will be gone in 300 million years,” O’Donoghue said. However, the Cassini spacecraft also detected even more ring matter was falling into Saturn’s equator. That means the rings likely have less than 100 million years to live.
This is a short amount of time compared to the fact that Saturn is over 4 billion years old – much older than its rings. That’s another bit of information Cassini was able to collect: Saturn’s rings are much younger than the planet itself. The planet’s rings formed between 10 million and 100 million years ago.
An artist created a mockup of what Saturn might look about 100 million years from now as its rings disintegrate. “The innermost rings disappear as they rain onto the planet first, very slowly followed by the outer rings,” NASA writes.