Irregular Pair

The oddball shapes of Saturn's small ring moons Prometheus and Epimetheus are discernible in the view from Cassini. Saturn's shadow carves a dark, diagonal swath across the ring plane, even occulting the outer edge of thin, knotted F ring. Prometheus is 102 kilometers, or 63 miles across, while Epimetheus is 116 kilometers, or 72 miles across.

Prometheus is visible inside the F ring near center, and Epimetheus is seen near the lower right corner. North on Saturn is to the upper right. The view is from beneath the ring plane.

The image was taken in visible light with the Cassini spacecraft narrow angle camera on Jan. 22, 2005, at a distance of approximately 2.6 million kilometers (1.6 million miles) from Saturn. The image scale is 15 kilometers (9 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 team is based at the Space Science Institute, Boulder, Colo.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.