This movie shows a bright arc of material flashing around the edge of
Saturn's G ring, a tenuous ring outside the main ring system.
The arc is the same feature identified in images of the G ring taken in
May 2005 (see PIA07718). Scientists have seen the arc a handful of times
over the past year, and it always appears to be a few times brighter than
the rest of the ring and very tightly confined to a narrow strip along the
inside edge of the G ring.
Imaging team members believe that this feature is long-lived and may be
held together by resonant interactions with the moon Mimas of the type
that corral similar ring arcs around Neptune.
The movie consists of 15 frames acquired every half hour over a period of
seven-and-a-half hours. The version in the lower panel is vertically
stretched by a factor of five to make the arc easier to see.
The clear-filter images in this movie sequence were acquired by the
Cassini spacecraft narrow-angle camera on April 25, 2006, at a distance
of 2 million kilometers (1.2 million miles) from Saturn. The image scale
on the sky at the distance of Saturn is about 24 kilometers (15 miles) per
pixel.
The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the mission for NASA's Science Mission Directorate, Washington, D.C. The
Cassini orbiter and its two onboard cameras were designed, developed and
assembled at JPL. The imaging operations center is based at the Space
Science Institute in Boulder, Colo.
For more information about the Cassini-Huygens mission visit
http://saturn.jpl.nasa.gov/. The Cassini imaging team
homepage is at http://ciclops.org.