Saturn has more than 60 moons, including giants like Titan and Enceladus, whole worlds with complex geologies and atmospheres. But embedded in its rings are smaller, rocky bodies that are just as mysterious in their own ways. One of the persistent questions is whether the rings themselves are the shattered remnants of past moons. Or, perhaps instead, these small moons could be built up from the material in the rings.



Cassini’s new evidence hints that the ring moons it studied have low densities, meaning they likely formed from gently colliding ring material, which is now loosely stuck together.



Since coming together, the moons have suffered complex histories. Small as they are, these ring moons show grooves and cracks from tidal stresses. They’re caught between Saturn’s massive tug and the smaller but more complicated gravitational pull from many larger moons. All this pulling means they’re being heated and pulled apart by the forces surrounding them.