Subscription Center
Mar 3, 2009
Saturn's G ring, a faint band of material near the outer bounds of the planet's famed ring system, hosts a bright arc about 90,000 miles (150,000 kilometers) long. The arc, or partial ring, which stretches through about a sixth of the G ring's length, is believed to provide the rest of the ring with dust and ice, but its evolution has remained a mystery.
Recent images from the Cassini spacecraft (at left) point to a moonlet embedded in the G ring. The moonlet, the Cassini team speculates, might help to repopulate the arc, and then the ring as a whole, with material as it suffers collisions with meteoroids or other small bodies within the ring.
See what we're tweeting about
Deadline: Jul 30 2013
Reward: $100,000 USD
The Seeker desires a method for producing pseudoephedrine products in such a way that it will be extremely difficult for clandestine che
Deadline: Jul 25 2013
Reward: Varies
This challenge provides an opportunity for Solvers to build a web-based or mobile “app” to explore data relationships in scholarly conte
Powered By: 
YES! Send me a free issue of Scientific American with no obligation to continue the subscription. If I like it, I will be billed for the one-year subscription.
