Per NASA, between 1655 and 1980, 13 moons of Saturn were discovered during ring plane crossings. For now, the disappearance of Saturn's rings is just a temporary, visual phenomenon.

New Hubble Space Telescope imagery of the Saturn show it's 'ring spokes' in orbit around the gas giant planet. Credit: ...

Our current view of Saturn means we're looking at the gas giant's famous rings edge on, making it impossible for telescopes on Earth to see them. This phenomenon is called a "ring plane crossing ...