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This mosaic of images from NASA's Cassini spacecraft shows the trail of a great northern storm on Saturn raging in full force. The contrast in the images has been enhanced to make the turbulent parts of the storm (in white) stand out without losing the details of the surrounding regions.

The head of the storm is the set of bright clouds near the left of the image. A clockwise-spinning vortex spawned by the storm shortly after it erupted in early December 2010 can be seen in the middle. The head of the storm moved very swiftly westward, while the vortex drifted more slowly westward.

Cassini's imaging camera obtained the images that went into this mosaic on March 6, 2011. The image is centered at about 0 degrees longitude and 35 degrees latitude.

In this image, scientists assigned red, green and blue channels to those visible-light colors. However, this view is not what a human eye would see at Saturn -- in enhancing the contrast, the natural color balance was not preserved. To human eyes, storm would have appeared more like a bright feature against a yellow background with less color variation, as is seen in PIA16724. In this color scheme, the brightness generally corresponds to the altitude of the cloud features. Bright white indicates highest cloud tops in the troposphere, and dark places indicate holes in the cloud layer. The subtle colors that become apparent in this enhanced-contrast view are probably produced by variation in the composition of clouds. However, the coloring agents responsible for producing these subtle hues remain unidentified.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. 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.

For more information about the Cassini-Huygens mission, visit http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov/.