From just above the plane of Saturn's rings, Cassini snapped this shot of Saturn showing that the shadow of its rings as a narrow band on the planet two months after Saturn's August 2009 equinox.
Cassini is looking toward the sunlit side of the rings from about 1 degree above the ringplane.
The novel illumination geometry that accompanies equinox lowers the sun's angle to the ringplane, significantly darkens the rings, and causes out-of-plane structures to look anomalously bright and cast shadows across the rings. These scenes are possible only during the few months before and after Saturn's equinox which occurs only once in about 15 Earth years. Before and after equinox, Cassini's cameras have spotted not only the predictable shadows of some of Saturn's moons (see PIA11657), but also the shadows of newly revealed vertical structures in the rings themselves (see PIA11665).
The image was taken with the Cassini spacecraft wide-angle camera on Oct. 16, 2009 using a spectral filter sensitive to wavelengths of near-infrared light centered at 752 nanometers. The view was obtained at a distance of approximately 1.5 million kilometers (932,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 83 degrees. Image scale is 86 kilometers (54 miles) per pixel.
The Cassini Equinox Mission is a joint United States and European endeavor. 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 was designed, developed and assembled at JPL. The imaging team consists of scientists from the US, England, France, and Germany. The imaging operations center and team lead (Dr. C. Porco) are based at the Space Science Institute in Boulder, Colo.