Terra and Aqua MODIS Instrument Status

Since launch, Terra MODIS has successfully operated for more than 10 years and Aqua MODIS for more than 8 years. Together, they have produced an unprecedentedly large amount of data products from their complementary morning and afternoon observations, over a wide spectral range from visible (VIS) to long-wave infrared (LWIR), and significantly benefited the science community for studies of changes in the Earth’s system and environment. On-orbit changes in sensor radiometric responses, spectral, and spatial characteristics are constantly monitored by a set of on-board calibrators (OBC), which include a solar diffuse, a solar diffuser stability monitor, a blackbody, and a spectroradiometric calibration assembly. In addition to using the OBC, lunar observations have been regularly scheduled and implemented in order to independently monitor changes in sensor radiometric responses. The MODIS Characterization Support Team (MCST) at NASA/GSFC is responsible for the operation and calibration of both MODIS instruments, including their Level 1B algorithm maintenance and improvements. This paper reports current status of both Terra and Aqua MODIS on-orbit operation and calibration activities and summaries their long-term radiometric, spectral, and spatial performance. Existing challenges, lessons learned, and future calibration efforts are also discussed.