“双小行星重定向测试”任务分析与小行星防御任务总体设计

Analysis of the“Double Asteroid Redirection Test”Mission and Overall Design of Asteroid Defense Mission

2022年9月27日,美国“双小行星重定向测试”(DART)任务对Didymos双小行星系统中的次星Dimorphos实施6.2km/s高速撞击,撞击使次星绕主星运行周期缩短32min。DART任务首次实现了人类对近地小行星偏转在轨演示,验证了深空高速撞击高精度制导控制、高速撞击偏转效果数值仿真和评估等实用化小行星防御关键技术,证明了动能撞击方式对小行星偏转的可行性。此次任务对人类未来主动应对小行星撞击威胁具有里程碑意义。本文对DART任务目标选择、任务设计、制导控制、偏转评估等方面进行分析,在此基础上提出了两种形式的小行星处置任务总体设计,并对任务轨道、地面可观测性、偏转效果等进行分析。

On 27 September 2022 CST,the Double Asteroid Redirection Test(DART)Mission implemented a kinetic impact into asteroid named Dimorphos,the secondary star in the Didymos binary asteroid system,at a speed of about 6.2 km/s,which shortened the substar’s orbital period by 32 minutes.The DARTmission realized the first in-orbit demonstration of Near Earth Asteroid Deflection.It verified the key technologies of practical asteroid defense such as high-precision guidance and control technology for high-speed impact in deep space,numerical simulation and evaluation of the deflection effect,and proved the feasibility of kinetic impact for asteroid deflection.This mission is a milestone for mankind to proactively deal with the threat of asteroid in the future.In this paper,the DART’s target selection principle,mission design,guidance and control technology,deflection evaluation method and other aspects are analyzed.On this basis,the overall design of two forms of asteroid disposal mission is proposed,and the mission orbit,ground observability and deflection effect are analyzed.