Story : http://www.astronomy.com/en/News-Observing/News/2012/04/Cassini sees objects bla
Scientists working with images from NASA's Cassini spacecraft have discovered strange half-mile-sized objects punching through parts of Saturn's F ring, leaving glittering trails behind them. These trails in the rings, which scientists are calling "mini-jets," fill in a missing link in astronomers’ story of the curious behavior of the F ring.
"I think the F ring is Saturn's weirdest ring, and these latest Cassini results go to show how the F ring is even more dynamic than we ever thought," said Carl Murray from Queen Mary University in London, England. "These findings show us that the F ring region is like a bustling zoo of objects from a half mile (0.8 kilometer) in size to moons like Prometheus that are 100 miles (160 km) in size, creating a spectacular show."
Scientists have known that relatively large objects like Prometheus - as long as 92 miles (148 km) across - can create channels, ripples, and snowballs in the F ring, but scientists didn't know what happened to these snowballs after they were created, Murray said. Some were surely broken up by collisions or tidal forces in their orbit around Saturn, but now scientists have evidence that some of the smaller ones survived, and their differing orbits mean they go on to strike through the F ring on their own.