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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.
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The Geoffrey Beene Foundation Alzheimer’s Initiative (GBFAI) is launching the 2013 Geoffrey Beene Global NeuroDiscovery Challenge whose
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This is a Reduction-to-Practice Challenge that requires written documentation and&
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