CICLOPS: Cassini Imaging Central Laboratory for OPerationS
In Her Wake

Daphnis leaves a path of disturbance on either side of her as she moves in her orbit within the Keeler Gap.

The gravity of the small moon (8 kilometers, 5 miles across) is enough to carve wavelike perturbations into the material of the outer A ring. The bright object to the right of the rings is a star, not a moon.

This view looks toward the unilluminated side of the rings from about 59 degrees above the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Jan. 31, 2009. The view was acquired at a distance of approximately 856,000 kilometers (532,000 miles) from Daphnis and at a Sun-Daphnis-spacecraft, or phase, angle of 63 degrees. Image scale is 5 kilometers (3 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.

For more information about the Cassini Equinox Mission visit, and

Credit: NASA/JPL/Space Science Institute
Released: March 10, 2009 (PIA 10595)
Image/Caption Information
  In Her Wake
PIA 10595

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Alliance Member Comments
Red_dragon (Mar 24, 2009 at 3:47 PM):
Thanks; I didn't remember that
CheshireCat (Mar 24, 2009 at 3:12 PM):
Red_dragon: The only other known moon to orbit within the rings (Pan) also creates these kinds of waves. It's how both moons were discovered, in fact.
Red_dragon (Mar 12, 2009 at 9:44 AM):
It would be interesting to know why Daphnis is able to create those features, while other moons that orbit within the rings not.