Posted: Fri, Aug 3, 2007, 8:19 AM ET (1219 GMT)
Scientists studying data from NASA's Cassini spacecraft have discovered what they believe is the origin for one of the more unusual rings surrounding the planet Saturn. In a paper published in this week's issue of the journal Science, scientists said Saturn's G ring is likely linked to an arc of relatively large ice particles in a part of the ring's inner edge. Collisions with micrometeoroids create smaller particles, which are then spread throughout the ring by plasma in Saturn's magnetic field. The origin of the G ring had previously puzzled scientists because, unlike some other rings, it is not linked to a moon that can supply it with source material.

Related Links:

•  SPACE.com article
•  New Scientist article
•  BBC article
•  NASA press release