In the solar system, Saturn's rings continue to be a mystery. Experts and scientists have been particularly interested in their ages. A new study conducted at the University of Colorado Boulder under the supervision of physicist Sascha Kempf has provided an estimate of the age of Saturn's rings. This discovery might offer an explanation for an issue that has confounded scientists for more than a century.
Saturn's rings are estimated to be no older than 400 million years old, according to research published in the journal Science Advances. As a result, the rings are significantly more recent than Saturn, which is thought to be roughly 4.5 billion years old.
According to Kempf, an associate professor in CU Boulder's Laboratory for Atmospheric and Space Physics (LASP), "In a way, we've gotten closure on a question that started with James Clerk Maxwell."
The researchers arrived at that conclusion by studying what might seem like an unusual subject: dust.
Kempf explained that tiny grains of rocky material wash through Earth's solar system on an almost constant basis. In some cases, this flux can leave behind a thin layer of dust on planetary bodies, including on the ice that makes up Saturn's rings.
In the new study, he and his colleagues set out to put a date on Saturn's rings by studying how rapidly this layer of dust builds up-a bit like telling how old a house is by running your finger along its surfaces.
"Think about the rings like the carpet in your house," Kempf said. "If you have a clean carpet laid out, you just have to wait. Dust will settle on your carpet. The same is true for the rings."
It was an arduous process: from 2004 to 2017, the team used an instrument called the Cosmic Dust Analyzer aboard NASA's late Cassini spacecraft to analyse specks of dust flying around Saturn. Over those 13 years, the researchers collected just 163 grains that originated from beyond the planet's close neighbourhood. But it was enough. Based on their calculations, Saturn's rings have likely been gathering dust for only a few hundred million years.
In other words, the planet's rings are new phenomena, arising (and potentially even disappearing) in what amounts to a blink of an eye in cosmic terms.
"We know approximately how old the rings are, but it doesn't solve any of our other problems," Kempf said. "We still don't know how these rings formed in the first place."
(With inputs from agencies)
