TerraSAR- X and TanDEM-X: Global Mapping in 3D using Radar M. Weber Infoterra GmbH, Germany Email: marco.weber@infoterra-global.com TerraSAR- X and TanDEM-X: Global Mapping in 3D using Radar The German Aerospace Center funded a study of a radar satellite system for mapping the Earth with unprecedented precision. Consisting of two high-resolution imaging radar satellites, TanDEM-X (TerraSAR-X add-on for Digital Elevation Measurement) will generate digital maps from any part of the world for a wide spectrum of research topics, as well as for commercial exploitation and security applications. A second TerraSAR-X satellite will be launched to orbit besides one presently under construction, forming a huge radar interferometer capable of measuring terrain height with 2 m accuracy, surpassing any technology available today. As radar is independent of sunlight and weather, the TanDEM-X will operate night and day, mapping the earth's surface even beneath clouds.