Although the sun is on the other side of Saturn in this dramatic image, some sunlight scatters through the uppermost part of the atmosphere to reach the Cassini spacecraft's cameras.
This image was taken at a high phase, or Sun-Saturn-spacecraft, angle of 172 degrees -- meaning Cassini was on the dark side of the planet at the time. Light passing through the atmosphere creates the bright arc seen from the top to the bottom of the image.
Saturn's rings, at middle right in the image, show the shadow of the planet being cast upon them. Just below the center of the image the light passing through Saturn's atmosphere is blocked from Cassini by the B ring.
The sun is now shining on the northern side of the rings, so the shadow of the rings on the lit side of the planet (away from Cassini) was cast down onto the southern limb of the planet, making the bright arc appear dark near the bottom middle of the image. The presence of the Cassini Division is illustrated in the small bit of scattered light it has allowed through near the bottom of the image.
For another dramatic view of Saturn in eclipse, see In Saturn's Shadow.
This view looks toward the northern, sunlit side of the rings from just above the ringplane.
The image was taken in visible green light with the Cassini spacecraft wide-angle camera on Feb. 13, 2010. The view was obtained at a distance of approximately 373,000 kilometers (232,000 miles) from Saturn. Image scale is 19 kilometers (12 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