Sep 15, 2022 - Science

Saturn's rings may be the remnant of a destroyed moon

Saturn seen in natural light
Saturn seen in 2010. Photo: NASA/JPL-Caltech/Space Science Institute

A large moon destroyed by Saturn may be responsible for the planet's distinctive rings, a new study suggests.

Why it matters: Understanding how a planet like Saturn and its moons work could help scientists piece together how our solar system — and perhaps others — evolved over the course of billions of years.

What they found: The new study in the journal Science this week models a large moon the researchers are calling Chrysalis being ripped apart about 160 million years ago, forming Saturn's rings.

  • According to the researchers, the moon broke apart after it grazed Saturn, with 99% of the moon falling into the planet's atmosphere and the other 1% creating the planet's rings.
  • The study also suggests Saturn's tilt today was created when the moon broke apart.
  • “It’s a pretty good story, but like any other result, it will have to be examined by others,” MIT's Jack Wisdom, one of the authors of the study said in a statement. “But it seems that this lost satellite was just a chrysalis, waiting to have its instability.”

Background: Scientists have long known that Saturn's rings were much younger than the planet itself. Saturn is about 4.5 billion years old. Its rings are thought to be about 100 million years old, but until now, it wasn't clear exactly why.

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