<h2>AAS 95-303</h2><h2>In-Flight Calibration of the Field of View Distortion for Spacecraft Attitude Sensors</h2><h4>W. S. Davis, J.A. Hashmall, A. R. Garber, H. K. Kang, and J. L. Moore, Computer Sciences Corporation, Lanham-Seabrook, MD</h4><h2> Abstract </h2>Star tracker and Sun sensor performance on recent space missions supported by the Goddard Space Flight Center Flight Dynamics Division has benefited from the combined calibration of the alignment and field of view distortion.  This paper presents the background and results of such calibrations for attitude sensors on the Compton Gamma Ray Observatory (GRO), Upper Atmosphere Research Satellite (UARS), and Extreme Ultraviolet Explorer.  This calibration has recovered the required performance of malfunctioning star trackers on GRO and UARS.  For UARS, this calibration has improved the performance of a normally functioning Sun sensor significantly beyond the manufacturer's specifications.<br><br>