火星电离层探测

Detection of Martian Ionosphere

火星已经成为深空探测的重要目标之一,登陆火星并在火星生存是人类探测火星的终极目标,因此电离层是必须了解的火星电磁环境.火星电离层探测包括直接探测和间接探测.直接探测精度高,有较高的空间分辨率,但是观测时间短,无法提供长期稳定的探测结果.对火星电离层的间接探测结果主要来自无线电掩星探测和顶部雷达探测.无线电掩星探测可实现对火星电离层整个电子密度剖面的长期稳定探测,但其空间水平分辨率较低,且可探测的电离层太阳天顶角范围受到地球与火星轨道的限制.顶部雷达探测对火星电离层的探测具有很高的时间分辨率和空间分辨率,且同样可进行长期稳定探测,为火星电离层研究提供了最新的支持.通过对火星电离层探测的基本方法及典型观测结果的分析,提出通过几种探测方法适当结合的方式,同时对火星电离层进行观测,能够大大推进对火星电离层的研究.

The exploration of Mars began in the early 1960s and has become the main subject of the space exploration recently.The Chinese deep space project（mainly focused on Mars）is developing.＂Land on Mars and live on Mars＂is the ultimate object for the Mars exploration and the Martian ionosphere is one of the environments to be understood necessarily.In this paper the basic methods of the Martian ionospheric detection and the typical results are introduced.The direct detection has the advantages of high precision,good spatial resolution,but it can not provide a long-term stable observation due to the short measuring time.The main indirect detection results of the Martian ionosphere come from the radio occultation method and the topside sounder.The radio occultation measurement provides a long-term stable detection of the whole profile of Martian ionosphere,but its horizontal resolution is not good and the Solar Zenith Angle（SZA）range of the measurement is limited by the orbits of Earth and Mars.The topside sounder can also provide a long-term stable measurement with high temporal and spatial resolutions,which gives new support for Martian ionospheric exploration.The combination of these detection methods will greatly improve the research of Martian ionosphere.