PASADENA, Calif., March 7 (UPI) -- U.S. scientists said NASA's Cassini spacecraft has detected what appears to be a ring surrounding Rhea, one of Saturn's largest moons.
It is the first time rings may have been found around a moon, the National Aeronautics and Space Administration said Thursday in a release.
Rhea, which is about 950 miles in diameter, is Saturn's second-largest moon.
"Until now, only planets were known to have rings, but now Rhea seems to have some family ties to its ringed parent Saturn," Cassini scientist Geraint Jones said in a report published in the journal Science.
NASA said Cassini detected an apparent debris disk that measured several thousand miles from end to end. Researchers said the particles that make up the disk probably range from the size of small pebbles to boulders.
