Data from the Cassini spacecraft have provided astronomers with a likely source of Saturn's mysterious G ring, which was discovered by Voyager probe.
The new findings by an international team of astronomers is published in the Aug. 2 edition of journal Science.
The G ring is a faint and narrow ring lying beyond the main set of rings and its existence at this location has been a mystery. It is not flanked by moons that might shepherd it and carve it out or infuse it with vapor. The G ring is more than 15,000 kilometers from the nearest satellite and 168,000 kilometers from the center of Saturn.
Matthew Hedman from Cornell University and his collaborators got a new view of the ring from the Cassini spacecraft and found that it contains a bright arc of material composed of icy bodies ranging in size from centimeters to a meter.
The ring is in a co-rotation with the major moon Mimas. Dust from the bring debris arc trails out into the ring and is stirred by Mimas' gravity.
The finding is evidence of the complex interaction between Saturn's moons, rings and magnetosphere. Studying this interaction is one of Cassini's objectives.