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This image shows examples of straighter, shorter, wider gullies that scientists on NASA's Dawn mission have found on the giant asteroid Vesta. The crater shown here is called Fonteia. The gullies in Fonteia -- called "Type-A" gullies -- are different from longer, more sinuous gullies that scientists have called "Type-B" gullies. Scientists think these gully varieties have different formation mechanisms.
This image was obtained by Dawn's framing camera on Feb. 7, 2012. North is up in this image.
An annotated version highlights the gullies with white lines.
The Dawn mission to Vesta and Ceres is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington D.C. UCLA is responsible for overall Dawn mission science. The Dawn framing cameras have been developed and built under the leadership of the Max Planck Institute for Solar System Research, Katlenburg-Lindau, Germany, with significant contributions by DLR German Aerospace Center, Institute of Planetary Research, Berlin, and in coordination with the Institute of Computer and Communication Network Engineering, Braunschweig. The framing camera project is funded by the Max Planck Society, DLR, and NASA/JPL.
More information about Dawn is online at http://www.nasa.gov/dawn and http://dawn.jpl.nasa.gov.