Space cooperation : Gravity Recovery and Climate Experiment (GRACE) Mission : Memorandum of understanding between the United States of America and Germany signed November 13 and December 10, 1998, and agreement amending and extending the memorandum of understanding signed February 26 and 27 and March 16, 2009, and agreements extending the memorandum of understanding, as amended and extended signed December 16, 17, and 18, 2009, signed June 10, 2010.