The oldest material on Earth which has yet been dated by man is a zircon mineral of 4.4 billion years old from a sedimentary gneiss in the Jack Hills of the Narre Gneiss Terrane of Australia. It is the most ancient fragment of the earthâ€™s crust so far identified, formed approximately 150 million years after the planet itself. In August of 2007, scientists reported finding the worldâ€™s oldest diamond crystals, encased inside the zircon crystals.
The image was acquired October 12, 2004, covers an area of 26.6 x 34.2 km, and is located near 26.2 degrees south latitude, 117.1 degrees east longitude.
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 December 18, 1999, on NASA's Terra satellite. 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 the 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.
More information about ASTER is available at http://asterweb.jpl.nasa.gov/.