This false color image of two density waves in Saturn's A ring was made
from the stellar occultation observed by Cassini's ultraviolet imaging
spectrograph when the spacecraft was 6.3 million kilometers (4 million
miles) from Saturn.
Bright areas indicate the denser regions of the rings. The bright bands
in the left part of the image are the "peaks" of a density wave caused by
gravitational stirring of the rings by Saturn's moon, Janus. A smaller
density wave in the right half of the image is produced by the moon
Pandora. The ultraviolet imaging spectrograph observed the brightness of
the star Xi Ceti as the rings passed in front of it, and the flickering
of the starlight was converted into the ring density depicted by the
image. The image represents a distance of about 724 kilometers (450
miles), and the smallest features are about one-half mile across.
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 Cassini-Huygens mission for NASA's Science Mission
Directorate, Washington, D.C. The Cassini orbiter was designed, developed
and assembled at JPL. The ultraviolet imaging spectrograph was built at,
and the team is based at the University of Colorado, Boulder.
For more information about the Cassini-Huygens mission, visit
http://saturn.jpl.nasa.gov and the ultraviolet imaging
spectrograph team home page, http://lasp.colorado.edu/cassini.