近地小行星轨道演化的数值研究与辛算法有效性的探讨

本文采用改进的显式辛算法（symplecticalgorithm）和嵌套的RKF7（8）积分器对43颗已命名（或编号）的近地小行星的轨道演化进行数值研究．在力学模型上，除考虑各大行星的引力振动外，还增加了后牛顿效应，而在算法上则着重探索辛算法在近地小行星轨道演化研究中的应用前景，特别是当小行星与某一大行星靠近时辛算法的有效性．本文的结果可为了解近地小行星的轨道演化状况和对它们进行监测提供可靠的信息．

A NUMERICAL RESEARCH ON THE ORBITAL EVOLUTION OF THE NEAs AND INVESTIGATION ABOUT THE EFECTIVENESS OF SYMPLECTIC ALGORITHM

In this paper a numerical research on the orbital evolution of 43 numbered NEAs has been made by adopting the improved explicit symplectic algorithm and the RKF7(8) integrator. For the mechanical model, the post-Newtonian effect has also been taken into account apart from considering the gravitational perturbations of major planets.The prospect that the symplectic algorithm might be suitable for studying the orbital evolution of NEAs is inveshgated, especially for the effectiveness of this algorithm in the case that the NEAs closely approach a major planet. The results of the paper can provide us with reliable information so that we might understand and obeerve the orbital evolutionary stage of NEAs.