On-orbit spectral characterization results for Terra MODIS reflective solar bands

The MODIS Protoflight Model (PFM), launched onboard the NASA s Earth Observing System (EOS) Terra spacecraft, has been in operation for more than three years. In addition to constant radiometric calibration activities, the sensor s on-orbit spectral bandpasses of the reflective solar bands (RSBs) with wavelengths from 0.41 to 2.2 micrometers have been measured (every three months) using the on-board Spectral Radiometric Calibration Assembly (SRCA). The spectral characteristics of the SRCA were calibrated pre-launch using the Spectral Measurement Assembly (SpMA). The MODIS on-orbit spectral characterization using the SRCA has been performing as designed and the key spectral parameters, with few exceptions, are well within the specification limits. This paper provides a brief review of the MODIS prelaunch spectral characterization. It focuses on the Terra MODIS instruments on-orbit spectral characterization activities, trending results, and comparisons with pre-launch characterizations and the specifications.