GRACE (Gravity Recovery and Climate Experiment) mission was a joint project between the National Aeronautics and Space Administration (NASA) and Deutsches Zentrum für Luft- und Raumfahrt (DLR). The twin satellites were built by Astrium and launched together with a Rockot in 2002, the mission was operated by the German Satellite Operations Centre and after fifteen years the mission was still producing outstanding results.
GRACE mission lasted three times as long as originally planned. The spacecraft ran out of fuel and the mission finished on 27 October 2017.
The primary science objective of GRACE was to measure the Earth's gravity field and its time variability with unprecedented accuracy. The secondary science objective was to obtain approximately 150 very precise globally distributed vertical temperature and humidity profiles of the atmosphere per day using the GPS radio occultation technique.
03 July 2017
The GRACE-A and B Microwave Assemblies (MWA) have been switched-off on 29 June 2017 13:40 UTC (GRACE-A) and 30 June 2017 18:37 UTC (GRACE-B), respectively. The GRACE-B Accelerometer Instrument Control Unit (ICU) on GRACE-B is off since 24 May 2017, the GRACE-A ICU has been switched-off on 29 June 2017 13:40 UTC.
Both activities are related to battery load reduction.
The switch-on of both MWAs is planned for approximately mid-August 2017.
07 June 2017
The GRACE-B Accelerometer Instrument Control Unit (ICU) has been switched-on again on 02 May 2017 at 12:08 and switched-off on 24 May 2017 at 18:40.
Mission Facts and Figures