Comparative analysis of gravitational potential modeling methods for irregularly shaped bodies: Application to asteroid (25143) Itokawa

Abstract

 Accurately modeling the gravitational potential of irregularly shaped celestial bodies, such as asteroids, is crucial for mission planning and orbital analysis. This study evaluates three prominent methods: the classical polyhedral approach, the Mascon gravitational model using a shaped polyhedral source, and the potential series expansion method (PSEM). The Classical Polyhedral Approach, noted for its precision near irregular surfaces, provides detailed gravitational field calculations but at a high computational cost due to its reliance on numerous triangular facets. The Mascon Model offers computational efficiency by approximating mass distributions with discrete point masses centered within tetrahedral elements, though accuracy declines close to the surface. Finally, PSEM introduces an analytical approach by representing the gravitational potential through a series expansion, offering a balance between accuracy and execution time suitable for dynamic orbital studies. Applying these models to asteroid (25143) Itokawa, we assess their performance in terms of accuracy, computational efficiency, and applicability for mission-critical scenarios. This comparative analysis provides insights into selecting appropriate modeling techniques based on mission requirements and computational constraints.