嫦娥一号卫星太阳风离子探测器数据分析

探月航天器与月球周围等离子体环境相互作用,表面将出现充放电效应,给航天器带来很多不利影响.表面充电电位对充放电的影响至关重要.评估探月航天器的充放电效应,首先需获得月球周围等离子体环境数据.嫦娥一号上搭载的两台太阳风离子探测器SWIDA/B是用来观测月球200 km轨道附近等离子体环境的探测仪器,获得了月球附近的太阳风速度、密度和温度.本文对2008年6月一个月内太阳风离子探测器SWIDA机获得的离子微分通量进行统计平均,得到太阳风离子微分通量能谱,并计算得到了月球200 km附近的太阳风速度(300.00—600.00 km·s-1)、密度(1—10 cm-3)和温度(1—20 eV).最后采用等效电路模型的方法计算得到了探月航天器表面充电电位范围为-7—-70 V.

Analysis of data obtained by the solar wind ion detector onboard the Chang’E-1 Lunar orbiter

The interaction between lunar plasma and spacecraft may cause surface charging/discharging effects, and degrade the performance of spacecraft. The charging potential is a key factor for discharging process. In order to evaluate charging/discharging effects, it is necessary to obtain the Lunar plasma environment. SWIDA/B on Chang’E-1 are the two scientific instruments of solar wind ion detector which could explore the plasma environment in the 200 km Lunar orbit, thereby deducing the solar wind bulk speed, density and temperature. In this paper we select the data in June 2008 derived from SWIDA sensor. First, we figure out the solar wind ion differential flux and energy spectrum, and then calculate the solar wind parameters such as velocity (300.00–600.00 km/s), plasma density (1–10 cm^-3) and plasma temperature (1–20 eV). Finally, we adopt an equivalent circuit model to compute the Lunar spacecraft surface charging voltage which is -7–-70 V.
Keywords： Lunar mission plasma environment spacecraft charging charging/discharging effects