A Pair of Shepherds
September 28, 2009
A pair of moons, Pandora and Prometheus, continue their shepherding duties near Saturn's thin F ring.
Pandora (81 kilometers, or 50 miles across) orbits outside the F ring and, with the inner shepherd moon Prometheus, helps to keep the narrow lanes of the F ring in check. The gravity of potato-shaped Prometheus (86 kilometers, or 53 miles across) periodically creates the streamer-channels seen here in the F ring. See Soft Collision to learn more.
This view looks toward the northern, sunlit side of the rings from about 10 degrees above the ringplane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Aug. 20, 2009. The view was obtained at a distance of approximately 2.3 million kilometers (1.4 million miles) from Saturn. Image scale is 13 kilometers (8 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.
Credit: NASA/JPL/Space Science Institute