Design challenges of ASTER in thermal infrared spectral region

The advanced spaceborne thermal emission and reflection radiometer (ASTER) to be mounted on the U.S.'s EOS-AM1 polar orbiting platform, scheduled for launch in 1998 by NASA, will be part of a remote sensing equipment complex whose purpose is to locate mineral resources and monitor the earth's environment. The ASTER, a Japanese mission, consists of three optical sensors -- the visible and near-infrared radiometer (VNIR), the short wavelength infrared radiometer (SWIR), and the thermal infrared radiometer (TIR), which has 5 spectral bands in the thermal infrared region (8 - 12 micrometers ). The TIR, which is the focus of this paper, is expected to provide high temperature and ground resolution in its acquisition of surface temperature information from the ground, oceans, and clouds. Such information will be useful in monitoring volcano activity, desertification, forestation and flora distribution, and the global climate as a whole. The TIR will also acquire information on the thermal radiation spectrum that will be useful in classifying rock formations and composition.