The moon Dione is eclipsed here by the narrow band of Saturn's rings, which in this image display one of the interesting ways that they transmit light. Dione is 1,118 kilometers (695 miles) across.
Researchers using NASA's Hubble Space Telescope noticed during the 1995 Saturn ringplane crossing that the brightness of the rings when viewed nearly edge-on was dominated by the F ring. In this image, the near and far edges of the F ring form the bright upper and lower boundaries of the rings. The dark strip in between is not empty (otherwise Dione would likely be visible there), but rather represents the material in the A and B rings.
This view shows principally the Saturn-facing hemisphere on Dione.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera on March 13, 2005, at a distance of approximately 2.1 million kilometers (1.3 million miles) from Tethys. Resolution in the image 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 team is based at the Space Science Institute, Boulder, Colo.
For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov. For additional images visit the Cassini imaging team homepage http://ciclops.org.