Thursday, February 11, 2010

Perspective View of Layered Mound in Gale Crater, Mars

This oblique view shows geological layers of rock exposed on a mound inside Gale Crater on Mars. This is a lower portion of the mound, with the crater floor at the left (and lowest) edge of the image. Layers near the bottom of the mound contain clay and sulfate minerals that indicate wet conditions. Overlying rock layers contain sulfates with little or no clay, consistent with these layers forming in an environment in which water was evaporating and Mars was drying out.

This view was created from a three-dimensional topographic model of the mound. The U.S. Geological Survey generated the model from a stereo pair of images taken by the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter. Observations of the site by the Compact Reconnaissance Imaging Spectrometer for Mars, on the same orbiter, yielded information about composition. The vertical dimension is exaggerated three-fold relative to the horizontal dimensions. The view is toward the southeast. The width of the area included in the image is about 1.5 kilometers (about 5,000 feet). The scale bar in the labeled version is 200 meters (656 feet).

1 comment:

電信 said...

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