“Cassini provided detail on the mass of Saturn’s moons and the physical characteristics of the rings. So mathematically speaking, we concluded that the moon Janus alone cannot keep the rings from spreading out,” said lead author of the new research Radwan Tajeddine from Cornell University in New York. The scientists discovered that confinement of the A ring is shared among the moons Pan, Atlas, Prometheus, Pandora, Epimetheus, Mimas and Janus. “All of these moons work as a group to contain the ring. Together they are strong. United they stand,” said Tajeddine.