Cassini Sees Saturn Rings. As of July, 1st 2004 (June, 60th EDT), NASA/European ESA/Italian Space Agency Cassini-Huygens mission successfully entered Saturn orbit setting the stage for a four-year study of Saturn's system. The craft just grazed the outermost part of the ring, coming to its closest to Saturn and the rings of the whole mission. This view in the ultraviolet is further confirming what Cassini saw. Rings are made of very pure water ice, with other parts, and the divisions, being made of a yet unidentified material, dubbed "dirt" by Cassini team. In this ultraviolet view this translates in red and turquoise. Red is for "dirty" and smaller ice particles as turquoise for cleaner and larger ones. The more distant from Saturn, the cleaner the ice. This pattern is seen here for the outer portion of C ring and inner portion of B ring, the latter beginning a little beyond picture center. The same would be visible further, with the A ring bright and pure ice, and the Cassini Division and the Encke gap redder as thinner and "dirtier". The unidentified material qualified "dirt" is similar in composition to material which was seen at Phoebe, this moon of Saturn which Cassini flew by and found being a planetesimal dating back 4.5 billion years, to the very origins of the solar system. Saturn rings might be the result of such a primordial planetesimal smashed at Saturn. picture courtesy NASA/JPL/University of Colorado