基于“嫦娥一号”激光测高数据的月球极区光照条件研究

Lunar polar illumination based on Chang′ E-1 laser altimeter

月球极区光照模型为研究月球车着陆点选择和水冰存在的探测提供了依据.利用"嫦娥一号"探月卫星获取的激光测高数据,得到了全月面高精度的数字高程模型(DEM),特别是在月球两极地区,地形细节清晰可见,为极区光照模型的建立提供了精确的数据基础.本文通过由测高数据建立的DEM和月球轨道参数相结合,采用地形最大高度角法,对月球极区的光照条件及其应用进行了研究和分析.光照率的计算周期为19年,考虑了黄道和白道交点进动的影响(18.6年).计算结果表明:(1)未发现有持续光照区;(2)有长久阴影区存在;(3)在南极或北极的夏季,撞击坑边沿高地处可以享受到连续的光照;(4)Shackleton撞击坑可以作为月球车着陆的首选目标之一.

The illumination condition of the lunar polar regions can be used to analyze the choice of ideal landing sites and to conduct the investigation of possible water ice deposits. The laser altimeter data obtained by ＇ChangrE-1＇ can provide high accuracy digital elevation models （DEM） for polar illumination model. In this study, polar illumination condition, by combining we establish the mathematical model to study the ~ChangI E-1＇ altimeter data and known parameters related to lunar orbit. The calculation period of illumination rate is 19 years, which is longer than the node precession period （18.6 years）. In this paper, the horizon method is used instead of the ray-tracing method, and the results show： （1） We donrt find the areas that receive permanent illumination; （2） There are regions that are in constant darkness： （3） The odge of thecraters can be found to be as continuous illumination region in the north summer or the south summer; （4） The Shackleton crater is one of the main targets as landing sites of the lunar rover.