From Saturn orbit, the Cassini spacecraft provides a perspective on the ringed planet that is never seen from Earth.
In our skies, Saturn's disk is always nearly fully illuminated by the sun. From this vantage point -- nearly in the ringplane, with the sun over to the right -- the Cassini spacecraft can see both lit and dark hemispheres, with the shadow of the rings on the northern hemisphere.
Saturn's low density and fast rotation cause its shape to deviate from spherical to a pronounced oblateness, very apparent here.
The image was taken using the Cassini spacecraft wide-angle camera and a filter sensitive to wavelengths of infrared light centered at 728 nanometers. The image was acquired on Sept. 30, 2005, at a distance of approximately 2.4 million kilometers (1.5 million miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 79 degrees. The mage scale is 139 kilometers (86 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