English: With the help of the double satellite formation, TerraSAR-X/TanDEM-X, it will now be possible to measure the entire land surface of the Earth, an area of some 150 million square kilometres, within a period of just three years and with high accuracy. The German radar satellite TerraSAR-X was launched on 15 June 2007. Launch of TanDEM-X is scheduled for October 2009. At present, this process is entirely free of competitors, and enjoys considerable respect around the globe, especially in the USA. These two satellites constitute a key project, which is intended to demonstrate, refine and further develop German expertise and ability to compete in the field of satellite-assisted radar technology.