In the far southeast corner of Libya, in the Libyan Desert, lie the uplifted massifs of Jebel Awenat and Jebel Arkenu. Both expose ancient Precambrian rocks, intruded by granites, and then overlain with sandstones. Folding and doming have produced these interesting shapes, rising above the surrounding sand sea. Presently, the area receives less than one inch of rain per year. Thousands of years ago, rainfall was more plentiful, and the Jebels were occupied by people, as attested by the numerous rock drawings. The images were acquired July 19, 2012, and July 31, 2013, cover an area of 66 by 67 kilometers, and are located at 22.1 degrees north, 24.8 degrees east.

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products.

The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying crop stress; determining cloud morphology and physical properties; wetlands evaluation; thermal pollution monitoring; coral reef degradation; surface temperature mapping of soils and geology; and measuring surface heat balance.

The U.S. science team is located at NASA's Jet Propulsion Laboratory, Pasadena, Calif. The Terra mission is part of NASA's Science Mission Directorate, Washington, D.C.

More information about ASTER is available at http://asterweb.jpl.nasa.gov/.