Three million measurement points in one square kilometer: Prof. Xiaoxiang Zhu and her team have set a world record in information retrieval from satellite data. Thanks to new algorithms, the researchers from the Technical University of Munich (TUM) succeeded in making four-dimensional point clouds of Berlin, Las Vegas, Paris and Washington, D.C. from images stacks of the TerraSAR-X radar satellite. Next the scientists plan to create four-dimensional models of all cities in the world.