... Cassini Spacecraft Crosses Saturn's Ring Plane . ... Credit: Cassini Imaging Team , ISS , JPL , ESA , NASA Explanation: If this is Saturn, where are the rings? ... Later that century, it became understood that Saturn 's unusual protrusions were rings and that when the Earth crosses the ring plane , the edge-on rings will appear to disappear. ... In modern times, the robot Cassini spacecraft orbiting Saturn now also crosses Saturn's ring plane. ... Moons appear as bumps in the rings. ...