Asteroids and comets have been the focus of several missions conducted by a number of space agencies. These bodies are often irregularly shaped making their gravitational fields irregular as well. Accurate models of these irregular gravitational fields are required if probes are to be confidently maneuvered in their vicinity. The polyhedral model is one such model which has been used for this purpose and works by approximating the bodies surface with a finite set of polygonal facets. The closed set of facets form a polyhedron from which the gravitational potential and acceleration can be determined analytically. In the present study, a hybrid model is proposed which utilizes a faster approximate model for the majority of facets and the more accurate polyhedral model near theoretical landing-sites. Results indicate that, though the approximate model is highly inaccurate near the surface, the polyhedral model patch creates a low-error window through which probe trajectories could be integrated.
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