Equatorial Troughs and Dark Material I
This Dawn FC (framing camera) image shows the equatorial troughs of Vesta running obliquely across the image. These troughs occur around most of Vesta's equatorial region and are one of its most striking features. They both overlie and are overlain by impact craters. A large linear structure seems to cut across these troughs in the bottom left side of the image. Also distinctive is the dark material which is associated with the troughs, impact craters (right side of image) and the dark hill (center of image). This dark hill remains dark from many different viewing angles in a selection of images, so its dark appearance is not just due to shadowing effects. Many possible formation mechanisms for this dark hill are currently under investigation.
NASA's Dawn spacecraft obtained this image with its framing camera on August 20th 2011. This image was taken through the camera's clear filter. The distance to the surface of Vesta is 2740km and the image resolution is about 260 meters per pixel.
The Dawn mission to Vesta and Ceres is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, Calif., for NASA's Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission science. The Dawn framing cameras were 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.