BackForward Satellite Programme: Gravity Recovery and Climate Experiment 

Programme details
Programme description
  • Series of dual-satellite systems with satellite-to-satellite ranging for observation of the gravity field.
  • Joint USA-Germany programme: NASA responsible of overall satellite development and large part of the payloads, DLR provider of the platform and the launch.  Shared system operations.
  • The platforms are actively stabilised over 3 axes.
  • The design life time of the satellites is 5 years.
  • Drifting orbits, the two satellites separated by 170 to 270 km.
  • The replacement policy is based on launching satellites couples at some 10-year intervals.
  • See detailed description here
Data circulation
  • Onboard data storage and downlink to Svalbard and several NASA and DLR acquisition stations.
  • Data are concentrated to the German Space Operations Center (GSOC) in Oberpfaffenhofen (Munich) in Germany and processed by DLR and the Center for Space Research (CSR) of the University of Austin (Texas).
Agencies NASA , DLR
Programme lifetime 2002 - 2026
Associated satellites and instruments

Note: red tag => no longer operational , green tag => operational , blue tag => planned