The Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument on the Earth Observing System (EOS)-AM1 and EOS-PM1 missions. It has 36 spectral bands with geometric instantaneous fields of view (GIFOV) of 0.25 km, 0.5 km, and 1.0 km at nadir. MODIS has completed system-level testing and is integrated onto the EOS-AM1 spacecraft, scheduled for launch in 1998. Raytheon Santa Barbara Remote Sensing (SBRS) has performed extensive characterization and calibration, demonstrating that MODIS meets or exceeds NASA's requirements. The MODIS Science Team has begun delivering algorithms to produce 42 standard data products post-launch, including atmospheric aerosols, snow cover, land and water surface temperatures, leaf area index, ocean chlorophyll concentration, and sea ice extent. MODIS system-level testing included measurements in ambient and thermal-vacuum environments to demonstrate specification compliance and enable post-launch radiometric calibration algorithms. These algorithms account for changes in response versus scan angle, response versus temperature, and response linearity. The onboard calibration systems, including the solar diffuser stability monitor (SDSM), blackbody (BB), and spectral radiometric calibration assembly (SRCA), were also tested to monitor MODIS performance post-launch. MODIS was originally conceived as two instruments, MODIS-N and MODIS-T, but MODIS-T was removed from development due to budget constraints. MODIS-N was placed on the EOS-PM platforms to enable morning and afternoon observations. MODIS has 36 bands, with three major band segments: seven for land cover and cloud/aerosol properties, nine for ocean color, and another set for atmospheric and surface properties. The MODIS design includes a double-sided, continuous rotation, paddle wheel scan mirror and a 10-km along-track field-of-view. The MODIS design includes four focal planes: visible (VIS), near infrared (NIR), shortwave and midwave infrared (SW/MWIR), and longwave infrared (LWIR). The SW/MWIR and LWIR focal plane assemblies are cooled to approximately 85 K by a passive radiative cooler. The MODIS electronics perform numerous tasks, including amplification and conversion of detector outputs, data formatting, command execution, control of twelve mechanisms, telemetry formatting, timing, focal plane temperature control, and power conditioning and distribution. MODIS has four onboard calibration modules, including a solar diffuser (SD), solar diffuser stability monitor (SDSM), spectral radiometric calibration assembly (SRCA), and blackbody (BB). These modules enable post-launch calibration and monitoring of MODIS performance. The MODIS has been tested extensively, with results showing excellent performance in terms of spatial, spectral, and radiometric characteristics. The MODIS has a dynamic range of over 7000, which is necessary to achieveThe Moderate Resolution Imaging Spectroradiometer (MODIS) is a key instrument on the Earth Observing System (EOS)-AM1 and EOS-PM1 missions. It has 36 spectral bands with geometric instantaneous fields of view (GIFOV) of 0.25 km, 0.5 km, and 1.0 km at nadir. MODIS has completed system-level testing and is integrated onto the EOS-AM1 spacecraft, scheduled for launch in 1998. Raytheon Santa Barbara Remote Sensing (SBRS) has performed extensive characterization and calibration, demonstrating that MODIS meets or exceeds NASA's requirements. The MODIS Science Team has begun delivering algorithms to produce 42 standard data products post-launch, including atmospheric aerosols, snow cover, land and water surface temperatures, leaf area index, ocean chlorophyll concentration, and sea ice extent. MODIS system-level testing included measurements in ambient and thermal-vacuum environments to demonstrate specification compliance and enable post-launch radiometric calibration algorithms. These algorithms account for changes in response versus scan angle, response versus temperature, and response linearity. The onboard calibration systems, including the solar diffuser stability monitor (SDSM), blackbody (BB), and spectral radiometric calibration assembly (SRCA), were also tested to monitor MODIS performance post-launch. MODIS was originally conceived as two instruments, MODIS-N and MODIS-T, but MODIS-T was removed from development due to budget constraints. MODIS-N was placed on the EOS-PM platforms to enable morning and afternoon observations. MODIS has 36 bands, with three major band segments: seven for land cover and cloud/aerosol properties, nine for ocean color, and another set for atmospheric and surface properties. The MODIS design includes a double-sided, continuous rotation, paddle wheel scan mirror and a 10-km along-track field-of-view. The MODIS design includes four focal planes: visible (VIS), near infrared (NIR), shortwave and midwave infrared (SW/MWIR), and longwave infrared (LWIR). The SW/MWIR and LWIR focal plane assemblies are cooled to approximately 85 K by a passive radiative cooler. The MODIS electronics perform numerous tasks, including amplification and conversion of detector outputs, data formatting, command execution, control of twelve mechanisms, telemetry formatting, timing, focal plane temperature control, and power conditioning and distribution. MODIS has four onboard calibration modules, including a solar diffuser (SD), solar diffuser stability monitor (SDSM), spectral radiometric calibration assembly (SRCA), and blackbody (BB). These modules enable post-launch calibration and monitoring of MODIS performance. The MODIS has been tested extensively, with results showing excellent performance in terms of spatial, spectral, and radiometric characteristics. The MODIS has a dynamic range of over 7000, which is necessary to achieve