A Tiny Moon Amidst Saturn's Rings

As promised last week, Cassini has delivered its best photos yet of the tiny moon Daphnis, the ringmoon that is responsible for carving out the skinny Keeler gap at the outer edge of Saturn's A ring. In addition to carving out the gap, its slight up-and-down motions, coupled with the fact that the particles in the ring that are closer to Saturn move faster in their orbits than Daphnis does, Daphnis excites vertical wave structures in the edge of the gap that make the sawtooth patterns visible in this image. …

See Planetary Society Weblog for links to further info.

Also see Space.com, NASA JPL, and Universe Today.