Saturn's Rings Could be Disappearing 48
fenimor writes "Saturn, the sixth planet from the Sun, is probably best known for its famous planetary rings. They extend from 6,630 km to 120,700 km above Saturn's equator, and are composed of silica rock, iron oxide, and ice particles. A massive eruption of atomic oxygen from Saturn's outer rings, seen by Cassini's ultraviolet camera, may be an indication that the planet's wispy E ring is eroding so fast that it could disappear within 100 million years if not replenished."
Re:What, it takes that long? (Score:4, Interesting)
Rings aren't really what I'd call "turbulent". Collisions speeds are very, very small. Eccentricities are practically non-existant by planetary standards. Things are pretty orderly, on the whole.
Worse, Larry Esposito (the real head of the UVIS team, despite what the article indicates) has floated the idea that rings might recycle themselves. It's a good idea, and his initial (crude) models indicate ring ages that are much too long. So it's not wholly clear that rings can't be primordial.
Still, the concensus remains that rings probably aren't an original feature of the solar system and that there is a source of ringy-goodness somewhere in the systems. So you're probably right overall: replenishment is likely occuring.
On an seperate note, what does the formation of icey planetesimals from the protosolar disk have to do with ring ages?