Saturn's Rings Are Ancient

gardenermike writes "Analysis of data from the Cassini probe suggests that Saturn's rings may be billions of years old, rather than the previously surmised millions. Previous research suggested that the rings were young, because of the lack of dark dust accumulation on their surfaces. However, the latest data suggests that the ring surfaces are even younger than previously thought, meaning, ironically, that the rings themselves are much older: they are not static enough to collect dust, but rather are continuously recycling material, with clumps continuously forming and disintegrating."

Re:Shouldn't this have been the default assumption

[CheshireCatCO]

There are many things in the solar system that are younger than 4.55 Gyr; a lot of asteroids, for example, are the results of more recent breakups. You have impact craters and other geologic features on practically all bodies. Honestly, assuming that anything you look at is primordial is a pretty daft assumption unless you can make *some* argument as to why it should be.

As for Saturn's rings, a modicum of research would tell you that there are both dynamical reasons to think that rings are younger (models say that they should grind down to dust relatively fast) as well as observational evidence: the amount of meteoric dust that they've accumulated is smaller than should be there if they were as old as the planet itself. In fact, had you read the article, you would have learned that.