Tropical Rainfall Measuring Mission Program

Joint NASA–JAXA Earth-observation program launched on 27 November 1997 to measure rainfall over the tropical and subtropical regions, where much of Earth’s precipitation occurs. TRMM carried the first precipitation radar flown in space together with the TRMM Microwave Imager and Visible/Infrared Scanner, producing three-dimensional storm and rainfall observations that supported climate research, numerical weather prediction, tropical-cyclone forecasting, flood and drought monitoring, and the later GPM mission. Science operations ended in April 2015 after fuel depletion.