Giant Dust Ring Discovered Around Saturn

Explanation: What has created a large dust ring around Saturn? At over 200 times the radius of Saturn and over 50 times the radius of Saturn's expansive E ring , the newly discovered dust ring is the largest planetary ring yet imaged. The ring was found in infrared light by the Earth-trailing Spitzer Space Telescope . A leading hypothesis for its origin is impact material ejected from Saturn's moon Phoebe , which orbits right through the dust ring 's middle. An additional possibility is that the dust ring supplies the mysterious material that coats part of Saturn's moon Iapetus , which orbits near the dust ring 's inner edge. Pictured above in the inset, part of the dust ring appears as false-color orange in front of numerous background stars.