Monday, December 13, 2010
The rings of Saturn (which we science writers are required by law to describe as "majestic" - but that's OK, because they are) are 95 percent ice. That posed a problem for scientists tyring to figure out how they formed. If they were bits from colliding moons (the planet has 63), there should be a lot more rock in there. A new theory says that a single, large, ice-covered moon was drawn in by Saturn's gravity, which stripped off the ice layers. The remnants in the rings have actually coalesced to make some of the small rock-and-ice moons we see today. One scientist refers to this as "cosmic recycling."