High Quality Content by WIKIPEDIA articles! TerraSAR-X, a German Earth observation satellite, is a joint venture being carried out under a public-private-partnership between the German Aerospace Center DLR and EADS Astrium GmbH; the exclusive commercial exploitation rights are held by the geo-information service provider Infoterra GmbH. TerraSAR-X was launched on June 15, 2007 and has been in operational service since January 2008. Following the launch of a second sister satellite, TanDEM-X in early 2010, the two satellites act as a pair.