Scientists Discover New Ring and Other Features at Saturn (JPL/SSI)

[eppur_se_muova]

eptember 19, 2006
(Source: Jet Propulsion Laboratory / Space Science Institute)

Saturn sports a new ring in an image taken by NASA's
Cassini spacecraft on Sunday, Sept. 17, during a
one-of-a-kind observation.

Other spectacular sights captured by Cassini's cameras
include wispy fingers of icy material stretching out tens of
thousands of kilometers from the active moon, Enceladus,
and a cameo color appearance by planet Earth.

The images were obtained during the longest solar
occultation of Cassini's four-year mission. During a solar
occultation, the sun passes directly behind Saturn, and
Cassini lies in the shadow of Saturn while the rings are
brilliantly backlit. Usually, an occultation lasts only about
an hour, but this time it was a 12-hour marathon.

Sunday's occultation allowed Cassini to map the presence of
microscopic particles that are not normally visible across
the ring system. As a result, Cassini saw the entire inner
Saturnian system in a new light.

The new ring is a tenuous feature, visible outside the brighter main rings of Saturn and inside the G and E rings, and coincides with the orbits of Saturn's moons Janus and Epimetheus. Scientists expected that meteoroid impacts on Janus and Epimetheus might kick particles off the moons' surfaces and inject them into Saturn orbit, but they were surprised that a well-defined ring structure exists at this location.


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http://saturn.jpl.nasa.gov/news/press-release-details.cfm?newsID=691