Light from the star Beta Crucis (Mimosa) breaks through the plane of the A ring in the center of this image of a stellar occultation.
Several of Cassini's remote-sensing instruments use occultations like this to measure the opacity of the ring system. Occultations involving Titan and Saturn are also used to study upper atmospheric haze layers.
The image was taken in visible light with the Cassini spacecraft wide-angle camera on Dec. 24, 2008. The view, which looks toward the unilluminated side of the rings from about 58 degrees above the ringplane, was obtained at a distance of approximately 825,000 kilometers (513,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 69 degrees. Image scale is 54 kilometers (34 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.