In 2009 NASA and the Japanese Ministry of Economy, Trade, and Industry (METI) released the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) global digital elevation model (DEM), which covers about 99% of the Earth's surface. The global DEM was built from 1.5 million individual scene-based ASTER DEMs. The global DEM is in GeoTIFF format with lat/long coordinates and a 1 arc-second (30 m) grid. It is referenced to the WGS84/EGM96 geoid. Accuracy is estimated to be 20 meters for elevations and 30 meters for horizontal data.
Based on measurements from NASA’s Terra spacecraft, a new 3D topographic map has been released, again as a joint effort by NASA and Japan. An additional 260,000 additional stereo-pair images were added to enhance the latest version of the DEM.