August 13, 2010
The Cassini spacecraft captures here one of its closest views of Saturn's ring-embedded moon Daphnis.
This image was taken July 5, 2010, at a distance of only about 75,000 kilometers (47,000 miles) from Daphnis. Seen at the upper left of this image, Daphnis (8 kilometers, or 5 miles across) appears in the Keeler Gap near the edge waves it has created in the A ring. The moon's orbit is inclined relative to the plane of Saturn's rings. Daphnis' gravitational pull perturbs the orbits of the particles of the A ring that form the Keeler Gap's edge, and sculpts the edge into waves having both horizontal (radial) and out-of-plane components. Material on the inner edge of the gap orbits faster than the moon so that the waves there lead the moon in its orbit. Material on the outer edge moves slower than the moon, so waves there trail the moon. See Wavy Shadows to learn more about this process.
Daphnis can also be seen casting a short shadow on the A ring.
This view looks toward the northern, sunlit side of the rings from about 14 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera at a sun-Daphnis-spacecraft, or phase, angle of 58 degrees. Image scale is 452 meters (1,483 feet) 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