Bright Duo

The moon Prometheus and a bit of Saturn's northern hemisphere are both brilliantly lit by the sun here, making the A ring seem dim in comparison.

The bright limb of Saturn's northern hemisphere can be seen through the A ring in the lower left of the image. Prometheus (86 kilometers, or 53 miles across) orbits in the Roche Division between Saturn's A and F ring.

For a similar view of Pandora, another of the F ring's shepherding moons, see The Shepherd and Saturn.

This view looks toward the sunlit side of the rings from about 20 degrees below the ringplane. The image was taken in red light with the Cassini spacecraft narrow-angle camera on May 25, 2009. The view was acquired at a distance of approximately 694,000 kilometers (431,000 miles) from Prometheus and at a Sun-prometheus-spacecraft, or phase, angle of 49 degrees. Image scale is 3.6 kilometers (2.2 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 .

Credit: NASA/JPL/Space Science Institute