双小行星系统内碎片演化的动力学机制研究

Dynamical mechanisms of ejecta evolution in binary asteroid systems

小行星表面风化层和附近空间碎片环境在撞击作用下会发生改变,部分小天体因此表现出活跃性,这为人类了解行星演化的动力学机制提供了关键线索.针对撞击作用下双小行星系统内碎片演化的动力学机制研究,本文建立了一个考虑具有不规则形状和非均质内部结构的双小行星的引力以及太阳系多种作用力的碎片演化的动力学模型,用于对碎片进行动力学仿真.在该模型中,本文开发了一个非结构化表面快速碰撞检测技术,用于检测碎片与小行星表面发生的接触碰撞.模型综合考虑了太阳光压力、行星引力、碎片在小行星表面的复杂反弹过程等因素的影响.本文设计了大规模碎片在双小行星系统内演化的仿真实验,分析了直径从0.01 mm到10 m的碎片的演化过程及其动力学机制.

The surface regolith layers of asteroids and their nearby space ejecta will change under impacts.As a result,some small bodies show increased activity,which provides key insights into the dynamics of planetary evolution.The paper focuses on the dynamical mechanisms of ejecta evolution in binary asteroid systems under impact effects.A dynamical model is established,considering the gravitational influence of binary asteroids with irregular shapes and heterogeneous internal structures,as well as various forces in the solar system,to simulate the dynamics of the ejecta.In this model,a non-structured surface rapid collision detection technique is developed for detecting contact collisions between the ejecta and the asteroid surface.The model comprehensively accounts for factors such as solar radiation pressure,planetary gravity,and complex features on the asteroid’s surface during the ejecta rebound process.Large-scale simulations of ejecta evolution in binary asteroid systems are conducted,analyzing the evolution processes and dynamical mechanisms of ejecta ranging from 0.01 mm to 10 m in diameter.