 Janus is a small inner moon of Saturn notable for having an orbit nearly identical to the orbit of the moon Epimetheus; the two swap orbital positions every four years.Mimas is a small, icy moon orbiting close to Saturn, notable for being scarred by Herschel crater, whose diameter is very wide compared to the total circumference of the moon.Enceladus is a small, icy moon orbiting close to Saturn, with an extremely bright surface and the geyser-like plumes of ice and water vapor that erupt from its southern polar region.