Twilight Realm

Dark shadows are an ever-present part of Saturn's already twilit world, where the Sun's rays are a hundred times more feeble than at Earth.

Here, the rings cast their silhouette upon the planet, which reciprocates with its own shade upon the rings at upper right. The moon Tethys also casts a dark spot onto Saturn's clouds.

This view looks toward the unilluminated side of the rings from about 21 degrees above the ringplane. The image was taken with the Cassini spacecraft wide-angle camera on Feb. 25, 2008 using a spectral filter sensitive to wavelengths of infrared light centered at 728 nanometers. The view was acquired at a distance of approximately 1.6 million kilometers (1 million miles) from Saturn. Image scale is 94 kilometers (58 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 . The Cassini imaging team homepage is at http://ciclops.org .

Credit: NASA/JPL/Space Science Institute