New developments in Earth Observation: using TerraSAR-X satellite data for monitoring geophysical parameters Petar Marinkovic and Ramon F. Hanssen TerraSAR-X is a new german X-band radar satellite launched on June 15, 2007. In this mission an operational spaceborne synthetic aperture radar (SAR) system with very high spatial resolution is set up, producing remote sensing products for commercial and scientific use. TerraSAR-X is a scientific and technological continuation of the successful Space Shuttle missions SIR-C/X and SRTM. Due to its polarimetric and interferometric capabilities as well as the high spatial resolution of up to 1m, the TerraSAR-X sensor is a very interesting tool for deformation monitoring using InSAR. Here we give an overview of first results using this sensor for geophysical applications, focusing mainly on subsidence monitoring, atmospheric parameter estimation and data quality evaluation. We focus on data acquired in the Groningen area. The potential as well as limitations of the X-band data will be summarized and compared to other sensors.