The Active Cavity Irradiance Monitor Satellite, or AcrimSat, mission spent 14 years in orbit monitoring Earth's main energy source, radiation from the sun, and its impacts on our planet. The satellite's ACRIM 3 instrument was the third in a series of satellite experiments that have contributed to a critical data set for understanding Earth's climate: a 36-year, continuous satellite record of variations in total solar radiation reaching Earth, or total solar irradiance. Solar irradience creates winds, heats the land and drives ocean currents, and therefore contains significant data that climatologists can use to improve predictions of climate change and global warming.


Mission Events


Dec. 14, 2013: AcrimSat goes silent and attempts to reestablish contact are unsuccessful. The loss of contact is likely due to an expected, age-related battery failure. The mission officially comes to an end on Aug. 8, 2014.

Key Discoveries


Scientific Instrument(s)

- Active Cavity Irradiance Monitor 3 (ACRIM 3)