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This paper presents preliminary results on the characterization of DirecTV-10 satellite with photometric observations during a glint season from 04:00 – 08:00 UTC on 23 February 2021 with U.S. Air Force Academy’s USAFA-16 telescope and simulations of the scene with the physics-based simulator; Digital Imaging and Remote Sensing Image Generation (DIRSIGTM) developed by the Rochester Institute of Technology (RIT). The objective of this work is to find the best set of operator-tuned parameters needed by the simulator to match as close as possible to observations. To accomplish this, the parameters of the optical system, the latitude/longitude and altitude of the telescope, the two-line element (TLE) set of the satellite, and atmospheric conditions at the time of the observation are input into DIRSIGTM to carry out the simulations. Furthermore, it is assumed that all parameters remain constant throughout the observations. The optical system USAFA-16 is a small aperture telescope equipped with a filter wheel which provides photometric, spectroscopic, and polarimetric images of the satellite. The results reported in this paper consist of an effort to correlate wide-band photometric images of the satellite with simulated images of these same wavebands. We use a high-fidelity CAD model of the satellite, and material properties such as pristine reflectance values, and BRDF measurements of the many components of the model which are provided by the Air Force Research Laboratory (AFRL), and ancillary information. We show preliminary results that demonstrate that DIRSIGTM may be used to characterize the satellite to some degree through the process of correlating calibrated magnitude patterns observed on photometric images. Further investigation is required to do the search of parameters in a systematic way, and move towards better agreement between observed and simulated data.
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