Ground Characterization of the Scanner for Radiation Budget (ScaRaB) Flight Model 1

Abstract

The Scanner for Radiation Budget (ScaRaB) is a satellite-based radiometer for measurements of the planetary radiation budget. It was launched in January 1994 on a Russian METEOR-3 platform and provided excellent data from February 1994 to March 1995. The radiometer is briefly described. Onboard calibration is performed by tungsten filament lamps and blackbody simulators. The onboard sources were characterized on ground, as well as the spectral response function of the instrument and the linearity of the channels. The ground measurements are described and the results are presented. The error in the blackbody calibration is estimated to 0.4% and to less than 1.5% for the various lamp sources. The lamp sources showed significant drifts during ground testing that could be corrected.