Abstract：This paper investigates the influence of a variety of mascon properties on the positions, topological conditions, and stability of the equilibria of minor bodies with application to asteroid 2867 Steins. Four types of mascon models are considered, the single-layer similar mascon, single-layer spherical mascon, multi-layer similar mascon, and multi-layer spherical mascon. The results show that the mascon may change the stability and topological conditions of the equilibrium points. For asteroid 2867 Steins, the topological condition and stability of external equilibrium point E4 differ between the mascon and the non-mascon cases. If the asteroid has no mascon, E4 is unstable and the topological condition is Case 5. If the asteroid has a mascon with the assumed density, E4 is stable and the topological condition becomes Case 1. The mascon case has larger distances between the external equilibrium point and the center-of-mass than the non-mascon case and smaller distances between the inner equilibrium point and the center-of-mass. If the position, density, and volume of two mascons are essentially the same, the shape has little effect on the equilibrium point position and no influence on the topological condition and stability of the equilibrium point. This study provides further understanding of the influence of the internal asteroid structure on the gravitational field around asteroids and provides a reference for gravitational field reconstruction, orbit design, and reliability analyses of asteroid exploration missions.
姜宇. 考虑质量瘤的小天体平衡点位置与稳定性[J]. 清华大学学报（自然科学版）, 2020, 60(3): 227-232.
JIANG Yu. Positions and stability of equilibrium points of minor celestial bodies with mascon. Journal of Tsinghua University(Science and Technology), 2020, 60(3): 227-232.
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2020, Vol. 60 
