Saturn’s Shiny Rings May Be Pretty Young

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https://eos.org/articles/saturns-shiny-rings-may-be-pretty-young

By Kimberly M. S. Cartier, Eos/AGU. 

Excerpt: ...Data from NASA’s Cassini mission showed how fast dust has been pelting the Saturnian system, revealing that for the rings to have remained as shiny and dust-free as they are, they can be only as much as 400 million years old, much younger than the planet itself. ...The Sun and its planets formed around 4.5 billion years ago, and many of the planets’ moons, including ours, followed not long after. Astronomers initially thought that Saturn’s rings formed during that early dynamical period, when large collisions were common. ...The rings’ orbits and compositions support the idea they are old. ...Measurements of the rainfall rate and the total mass of the rings from NASA’s Cassini spacecraft, which orbited Saturn for 13 years, suggested that the rings must be far younger than the planet; otherwise, they would have disappeared already. Cassini also revealed that the rings are fairly shiny, having accumulated only a small amount of cosmic dust—tiny silicate particles that come from the far reaches of the solar system or beyond.... 

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