Spacecraft shows Saturn moon might have rings

1. Cassini spacecraft detected what might be a large debris disk around Rhea
2. If confirmed, would mark first time rings were found around a moon
3. Flyby pictures were taken in 2005
4. Findings were published March 7 issue of the journal Science

PASADENA, California (AP) -- New observations by a spacecraft suggest Saturn's second-largest moon may be surrounded by rings.

If confirmed, it would the first time a ring system has been found around a moon.

The international Cassini spacecraft detected what appeared to be a large debris disk around the 950-mile-wide moon Rhea during a flyby in 2005. Scientists proposed that the halo likely contained particles ranging from the size of grains to boulders.

The finding was described in a study published in the March 7 issue of the journal Science.

Unlike the rings around Saturn, Jupiter, Uranus and Neptune, the apparent arcs around Rhea remain invisible and have not been directly seen. Scientists inferred their existence based on measurements by Cassini, which detected a drop in electrons on both sides of the moon, suggesting the presence of rings was absorbing the electrons.

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Rhea with rings? what next are we gonna find in and around Saturn?

[edit on 7-3-2008 by Enceladus]

Saturn's Moon Rhea Also May Have Rings

PASADENA, Calif. - NASA's Cassini spacecraft has found evidence of material orbiting Rhea, Saturn's second largest moon. This is the first time rings may have been found around a moon.

A broad debris disk and at least one ring appear to have been detected by a suite of six instruments on Cassini specifically designed to study the atmospheres and particles around Saturn and its moons.

Evidence for a debris disk in addition to this tenuous dust cloud came from a gradual drop on either side of Rhea in the number of electrons detected by two of Cassini's instruments. Material near Rhea appeared to be shielding Cassini from the usual rain of electrons. Cassini's Magnetospheric Imaging Instrument also detected sharp, brief drops in electrons on both sides of the moon, suggesting the presence of rings within the disk of debris. The rings of Uranus were found in a similar fashion, by NASA's Kuiper Airborne Observatory in 1977, when light from a star blinked on and off as it passed behind Uranus' rings.

Link to Nasa web site