NASA, Japan Release Improved Topographic Map of Earth
NASA and Japan released a significantly improved version of the most complete digital topographic map of Earth on Monday, produced with detailed measurements from NASA's Terra spacecraft. The map, known as a global digital elevation model, was created from images collected by the Japanese Advanced Spaceborne Thermal Emission and Reflection Radiometer, or ASTER, instrument aboard Terra. So-called stereo-pair images are produced by merging two slightly offset two-dimensional images to create the three-dimensional effect of depth. The first version of the map was released by NASA and Japan's Ministry of Economy, Trade and Industry (METI) in June 2009. Read more