Location and Accuracy Validation of Lunar Landing Point Based on Multi-source Imagesormalsize

High-precision positioning of the landing site is a critical step in the mission and an important prerequisite for surface operations of the lander and rover. In this paper, a high-precision positioning method of the landing site was designed based on image feature matching and multiple image localization methods. And the positioning experiment and accuracy validation were carried out in Chang'E-3 landing site. On the basis of high-precision image matching and geometric transformation, the matching precision between the sequent descent images reached sub-pixel, and the matching accuracy between LRO NAC image and medium-resolution descent image was better than 1 pixel. The landing position was calculated to be (44.1196°N, 19.5148°W). This method comprehensively utilized multi-source images, and didn't entirely depend on the mapping accuracy of the landing base map. It was a further refinement of the matching results between the images and landing base map. So, this high-precision positioning method can be applied in future deep space exploration missions.