Aerosol polarimetry sensor for the Glory Mission

This paper describes the Glory Mission Aerosol Polarimetry Sensor (APS) being built by Raytheon under contract to NASA's Goddard Space Flight Center. Scheduled for launch in late 2008, the instrument is part of the US Climate Change Research Initiative to determine the global distribution of aerosols and clouds with sufficient accuracy and coverage to establish the aerosol effects on global climate change as well as begin a precise long-term aerosol record. The Glory APS is a polarimeter with nine solar reflectance spectral bands that measure the first three Stokes parameters vector components for a total of 27 unique measurements. In order to improve the reliability and accuracy of the measurements, additional 9 redundant measurements are made, yielding a total of 36 channels. The sensor is designed to acquire spatial, temporal, and spectral measurements simultaneously to minimize instrumental effects and provide extremely accurate Raw Data Records. The APS scans in the direction close to of the spacecraft velocity vector in order to acquire multi-angle samples for each retrieval location so that the Stokes parameters can be measured as functions of view angle.