UV-IR Robust, Accurate Earthshine and Skyshine (RAES) Model

Target detection, classification and tracking by missile defense sensor systems from post boost phase through mid-course to reentry is affected not only by background contrast but also by the irradiance contributing to the target signature by extended sources including direct and reflected sunshine, earthshine, airglow, moonshine and other celestial sources. The total irradiance on the target from Earthshine/Skyshine and Airglow emissions is important for predicting signature during dawn, dusk and night time conditions. In addition, external sources, including solar heating, earth reflected solar and earth thermal emissions, make important contributions to target heating. The earthshine/skyshine external sources are difficult to model accurately and have not received adequate attention in existing signature models. To fulfill MDA needs, Spectral Sciences, Inc. (SSI) proposes in this SBIR Phase I to provide a first principles detailed model for accurate determination of earthshine and skyshine radiance in the ultraviolet, visible and infrared spectral regions. To develop this model, dubbed Robust Accurate Earthshine Skyshine (RAES), we will build on SSI’s extensive experience in atmospheric radiance models, and team with Photon Research Associates (PRA) to incorporate their terrain and cloud models, and with Teledyne Solutions Inc. (TSI), the developer of the OSC target model.