Using the Moon for MODIS On-orbit Spatial Characterization

The moon is a very stable reference source that has been used for the space-borne sensors’ radiometric calibration and/or radiometric stability monitoring. In this paper, we present an approach that uses the sensors’ on-orbit lunar observations for their spatial characterization and apply the method to the MODIS instruments that are currently operating onboard NASA EOS Terra and Aqua satellites. Both MODIS instruments perform monthly lunar observations. The spatial characterization results derived from the lunar observations using this algorithm are compared with those obtained from the MODIS Spectro-Radiometric Calibration Assembly (SRCA), which is an on-board calibrator capable of performing spatial characterizations for all MODIS spectral bands. The new approach can be applied to other remote sensing instruments.