CICLOPS: Cassini Imaging Central Laboratory for OPerationS
Engulfing a Gap

The shadow of the moon Tethys is cast onto Saturn's A ring, almost blanketing the Enke Gap.

The novel illumination geometry created as Saturn approaches its August 2009 equinox allows moons orbiting in or near the plane of Saturn's equatorial rings to cast shadows onto 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. To learn more about this special time and to see a movie of a moon's shadow moving across the rings, see PIA11651 and PIA11660.

This view looks toward the sunlit side of the rings from about 29 degrees below the ringplane. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on May 25, 2009. The view was acquired at a distance of approximately 759,000 kilometers (472,000 miles) from Saturn and at a Sun-Saturn-spacecraft, or phase, angle of 56 degrees. Image scale is 4 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: July 20, 2009 (PIA 11539)
Image/Caption Information
  Engulfing a Gap
PIA 11539

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Alliance Member Comments
stowaway (Jul 20, 2009 at 4:45 PM):
Great Glooming Gap Engulfers Batman - this one's a ten
Red_dragon (Jul 20, 2009 at 8:25 AM):
Dramatic thanks to the perspective tricks of Cassini's NAC; another fine work from CICLOPS.