论文标题：Descent trajectory reconstruction and landing site positioning of Chang’E-4 on the lunar farside

期刊：Nature Communications

作者：Jianjun Liu, Xin Ren, Wei Yan, Chunlai Li, He Zhang, Yang Jia, Xingguo Zeng, Wangli Chen, Xingye Gao, Dawei Liu, Xu Tan, Xiaoxia Zhang, Tao Ni, Hongbo Zhang, Wei Zuo, Yan Su, Weibin Wen

发表时间：2019/09/24

数字识别码： 10.1038/s41467-019-12278-3

微信链接：https://mp.weixin.qq.com/s/_wOhmiRkGhCGNZjOWSURng

《自然-通讯》本周发表的一篇论文Descent trajectory reconstruction and landing site positioning of Chang’E-4 on the lunar farside精确定位了“嫦娥四号”的着陆位置，并对“嫦娥四号”的落月过程进行了重构。

图1：嫦娥四号的着陆点 图源: Liu等

2019年1月3日，中国的“嫦娥四号”探测器成功着陆在月球背面的冯•卡门撞击坑内。整个着陆过程没有来自地球的无线测控和遥测数据，全部依靠自主控制。

“嫦娥四号”降落相机拍摄的影像图会在着陆后通过“鹊桥”中继卫星传回地球。中国科学院国家天文台的李春来和同事利用这些图像对“嫦娥四号”的着陆轨迹进行了重构。根据降落相机和“玉兔二号”巡视器传回的影像图，作者指出“嫦娥四号”着陆在一个退化撞击坑的缓坡上，距离北边一个直径25米的撞击坑边缘很近，且着陆点周围共有五个撞击坑。随后，作者根据另一台导航相机拍摄的图像，精确计算出“嫦娥四号”的着陆点为东经177.5991°，南纬45.4446°，高程-5935米。

该研究为将来航天器在太阳系内的自主着陆（比如在小行星表面着陆）提供了依据。

摘要：Chang’E-4 (CE-4) was the first mission to accomplish the goal of a successful soft landing on the lunar farside. The landing trajectory and the location of the landing site can be effectively reconstructed and determined using series of images obtained during descent when there were no Earth-based radio tracking and the telemetry data. Here we reconstructed the powered descent trajectory of CE-4 using photogrammetrically processed images of the CE-4 landing camera, navigation camera, and terrain data of Chang’E-2. We confirmed that the precise location of the landing site is 177.5991°E, 45.4446°S with an elevation of −5935 m. The landing location was accurately identified with lunar imagery and terrain data with spatial resolutions of 7 m/p, 5 m/p, 1 m/p, 10 cm/p and 5 cm/p. These results will provide geodetic data for the study of lunar control points, high-precision lunar mapping, and subsequent lunar exploration, such as by the Yutu-2 rover.

（来源：科学网）