强不规则天体引力场中的动力学研究进展

小行星探测与彗星探测是深空探测的重要方面。一般来说,小行星和彗星因质量都不足以使得万有引力克服应力达到流体静力学平衡,而具有强不规则的外形。研究强不规则天体引力场中的动力学行为及其内在机制,是探测器被不规则天体捕获并对其形成近距离探测轨道的基础。从引力场模型和动力学行为两个方面综述了强不规则天体引力场中动力学的研究进展,在引力场模型的研究方面介绍了强不规则天体引力场建模的球谐函数摄动展开模型、简单特殊体模型及多面体模型的研究现状,在动力学机制的研究方面介绍了强不规则天体引力场中的周期轨道和拟周期轨道、平衡点、流形、分岔与共振以及混沌运动的研究现状,指出了这些方面研究的重点与难点。分析了强不规则体引力场中动力学的研究趋势。

Research Trend of Dynamics in the Gravitational Field of Irregular Celestial Body

Both asteroid and comet exploration are important areas in the deep space exploration. The mass of an asteroid or a comet is not big enough, so its gravitational force is much smaller than the stress to satisfy the hydrostatic equilibrium, which makes the minor celestial body irregular-shaped. The research of dynamical behaviours and mechanisms in the gravitational field of irregular celestial body is the basis of minor celestial body exploration, including the catching of the explorer and the design of the orbit around the minor celestial body. This paper summarizes the research progress of the dynamics in the gravitational field of irregular celestial body through gravitational models and dynamical mechanisms. The research situation of gravitational models such as the Legendre polynomial model, the simple-shaped model and the polyhedron model are presented. In addition, the research situation of dynamical mechanisms such as the periodic orbits and quasi-periodic orbits, equilibrium points, manifolds, bifurcations and resonances, chaos, are also presented. Besides, we have analyzed key points and difficult points of these researches. Finally, the research trend of the dynamics in the gravitational field of irregular celestial body is discussed.