SURFACE IMAGING TECHNOLOGIES FOR NASAS EARTH OBSERVING SYSTEM

The Earth Observing System (EOS) is the major element in the National Aeronautic and Space Administration's Mission to Planet Earth. It will be a 15-year-long mission, employing space-based instrumentation and in situ measurements to provide a long-term, contiguous, calibrated, a nd validated data set that addresses geophysical and biochemical pheno mena occurring in the Earth system. The EOS suite of satellites includ es sun-synchronous, polar-orbiting spacecraft with morning or afternoo n equator-crossing times. The EOS-AM series, the first of which is sla ted for launch in June 1998, will address geophysical and biogeochemic al processes occurring at or near the Earth's surface; the EOS-PM plat forms will address atmospheric phenomena, including the interaction be tween clouds and radiation. Synergy and complementarity within and bet ween these and other platforms will play a major role in acquiring hig h-quality data. We discuss the following instruments: Moderate Resolut ion Imaging Spectroradiometer (MODIS), Advanced Spaceborne Thermal Emi ssion and Reflection Radiometer (ASTER), Multifrequency Imaging Microw ave Radiometer (MIMR), Multiangle Imaging Spectroradiometer (MISR), an d Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit/Microw ave Humidity Sounder) (AIRS/AMSU/MHS). Instrument heritage, design, ca pabilities, and realization are discussed in terms of satisfying scien tific requirements. We also discuss the synergy resulting from cross-c alibration of the instruments and validation of their resulting data p roducts.