The two moons are constantly exchanging orbits. This makes them seem to revolve around each other as they orbit Saturn. Whichever of the two moons is in the orbit closer to Saturn is moving faster because of Saturn's gravity. The gravities of the two moons also pull them toward each other. The moon in the closer, faster orbit is drawn outward into a farther orbit, and the moon in the farther, slower orbit is drawn into the closer orbit. This cycle of switching orbits continues over and over, as the two moons move together around Saturn.
Why do rings exist?
This question was answered in 1848 by a French mathematician named Edouard Roche. He
