Prometheus pulls away from an encounter with Saturn's F ring, leaving behind a reminder of its passage.
Prometheus (102 kilometers, or 63 miles across) approaches closely to the F ring once during each circuit around Saturn, disturbing the orbits of the small particles in the ring and creating a streamer of material that then shears out, following the moon as it speeds off.
This view looks toward the unilluminated side of the rings from about 37 degrees above the ringplane. Prometheus is brightly lit by the Sun on one side and lit more modestly by Saturn's reflected light on the other side.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 18, 2007 at a distance of approximately 2 million kilometers (1.2 million miles) from Prometheus and at a Sun-Prometheus-spacecraft, or phase, angle of 87 degrees. Image scale is 12 kilometers (7 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/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.