TanDEM-X Mission Status

In 2010 the first formation flying radar system was built by extending the TerraSAR-X synthetic aperture radar mission by a second, TerraSAR-X-like satellite called TanDEM-X. The resulting large single-pass radar interferometer features flexible baseline selection. This enables the acquisition of highly accurate cross-track interferograms not impacted by temporal decorrelation and atmospheric disturbances. The primary objective of the mission – the generation of a global digital elevation model with unprecedented accuracy – was achieved in 2016. Up to 2020 the mission acquired data for a global change layer (TanDEM-X DEM 2020) revealing the height changes relative to the first dataset. After so many years in orbit both spacecraft show aging effects. There are already several redundant units in operation on both satellites, but they are still fully functional and have enough consumables for several additional years. Repeated height measurements allow the observation and quantification of dynamic processes on the Earth’s surface such as deforestation or melting of glaciers and ice sheets. Therefore, bistatic operations continue in the TanDEM-X 4D Phase with a focus on changes in the cryosphere, biosphere and densely populated areas and regions with larger height changes.