Depth of Field
Cassini puts the enormous distances in the Saturn system in perspective with this view of Rhea and Prometheus.
Rhea (1,528 kilometers, or 949 miles across) sits in the foreground, while Prometheus (102 kilometers, or 63 miles across) lingers barely visible near the rings about 400,000 kilometers (250,000 miles) beyond. Saturn's cloud tops are about 80,000 kilometers (50,000 miles) farther still.
This view looks toward the unilluminated side of the rings from less than a degree above the ringplane.
The image was taken with the Cassini spacecraft narrow-angle camera on Aug. 13, 2007 using a spectral filter sensitive to wavelengths of infrared light centered at 750 nanometers. The view was acquired at a distance of approximately 4.1 million kilometers (2.5 million miles) from Saturn. Image scale is 24 kilometers (15 miles) per pixel on Saturn and 21 kilometers (13 miles) per pixel on Rhea.
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/home/index.cfm. The Cassini imaging team homepage is at http://ciclops.org.