A new terminal guidance sensor system for asteroid intercept or rendezvous missions

This paper presents the initial conceptual study results of a new terminal guidance sensor system for asteroid intercept or rendezvous missions, which explores the use of visual, infrared, and radar devices. As was demonstrated by NASA׳s Deep Impact mission, visual cameras can be effectively utilized for hypervelocity intercept terminal guidance for a 5 kilometer target. Other systems such as Raytheon׳s EKV (Exoatmospheric Kill Vehicle) employ a different scheme that utilizes infrared target information to intercept ballistic missiles. Another example that uses infrared information is the NEOWISE telescope, which is used for asteroid detection and tracking. This paper describes the signal-to-noise ratio estimation problem for infrared sensors, minimum and maximum range of detection, and computational validation using GPU accelerated simulations. Small targets (50-100 m in diameter) are considered, and scaled polyhedron models of known objects, such as the Rosetta mission׳s Comet 67P/Churyumov-Gerasimenko, 101,955 Bennu, target of the OSIRIS-REx mission, and asteroid 433 Eros, are utilized. A parallelized ray tracing algorithm to simulate realistic surface-to-surface shadowing of a given celestial body is developed. By using the simulated models and parameters given from the formulation of the different sensors, impact mission scenarios are used to verify the feasibility for intercepting a small target.