The shadow of the moon Tethys stretches across Saturn's A ring before fading into the B ring as the shadow extends towards the lower right of this image.
This view looks toward the unilluminated side of the rings from about 27 degrees above the ringplane. The shadow appears truncated by the dense B ring. Tethys (1062 kilometers, or 660 miles across) is not shown.
As Saturn approaches its August 2009 equinox, the planet's moons cast shadows onto the rings. To learn more about this special time and to see an earlier movie of a moon's shadow moving across the rings, see Moon Shadow in Motion. To watch a movie of Tethys's shadow seen from a similar viewing geometry, see Shadow from the Dark Side.
This image was taken in visible light with the Cassini spacecraft wide-angle camera on May 20, 2009. The view was acquired at a distance of approximately 1.4 million kilometers (870,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 128 degrees. Image scale is 82 kilometers (51 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