Each of the little Space eggs resides within its own ring arc--which is a fragmentary ring of Saturn. One hypothesis states that glittering ice crystals swarming around in the ring arc might be floating down to the surface of Methone, filling in its impact craters or other rough topography. This is something that is thought to have occurred on two other small, icy moons of Saturn--Atlas and Pan. Icy stuff swarming around in Saturn's rings apparently piled up around each moonlet's equator.
"Cassini's seven-plus years... have shown us how beautifully dynamic and unexpected the Saturn system is," commented project scientist Dr. Linda Spilker of NASA's JPL to Time Magazine's online edition on March 23, 2012.
Tracing our Moon's changing porosity may ultimately help astronomers to track the trajectory of the invading army of a multitude of lunar impactors, that occurred during the Late Heavy Bombardment, 4 billion years ago.