CICLOPS: Cassini Imaging Central Laboratory for OPerationS
Spotty Iapetus

At high resolution, terrain in the transition region between bright and dark hemispheres on Iapetus reveals a spotty appearance reminiscent of a Dalmatian. The bright material on the frozen surface of Iapetus (1,471 kilometers, 914 miles across) is water ice and the dark material is likely carbonaceous in composition.

The dark material is preferentially found at the bottoms of craters. Bright water ice forms the "bed rock" on Iapetus, while the dark, presumably loose material apparently lies on top of the ice.

The terrain seen here is also visible in PIA08383, but is viewed here at higher resolution.

The mosaic consists of two image footprints across the surface of Iapetus. The view is centered on terrain near 42 degrees south latitude and 209.3 degrees west longitude, on the anti-Saturn facing hemisphere. Image scale is approximately 32 meters (105 feet) per pixel.

The clear spectral filter images in this mosaic were obtained with the Cassini spacecraft narrow angle camera on Sept. 10, 2007 at distances ranging from 5,363 to 5,884 kilometers (3,332 to 3,656 miles) from Iapetus.

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 Cassini-Huygens mission for NASA's Science Mission Directorate, Washington, D.C. 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-Huygens mission, visit and the Cassini imaging team home page,

Credit: NASA/JPL/Space Science Institute
Released: October 8, 2007 (PIA 08382)
Image/Caption Information
  Spotty Iapetus
PIA 08382

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