GRACE and GRACE-FO

The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of its science mission in October 2017. The two satellites were sometimes called Tom and Jerry, a nod to the famous cartoon. The GRACE Follow-On (GRACE-FO) is a continuation of the mission on near-identical hardware, launched in May 2018. On March 19, 2024, NASA announced that the successor to GRACE-FO would be Gravity Recovery and Climate Experiment-Continuity (GRACE-C), to be launched in or after 2028.