Characterization of Meter‐to Hectometer‐Scale Craters and Centimeter‐Sized Rocks in the Chang'e‐6 Landing Site Measured From Descent Imagery

Abstract China's Chang'e‐6 (CE‐6) probe successfully landed in the Apollo Basin within the South Pole‐Aitken Basin on 2 June 2024 (Beijing Time), and returned the first lunar farside samples in human history. The descent camera captured hundreds of high‐resolution images during the descending and landing. High‐resolution digital orthophoto map (DOM) and digital terrain model (DTM) were generated from these images. We created catalogs of meter‐to‐hectometer craters and centimeter‐sized rocks from the generated DOMs and DTMs of 0.03 m/pixel (Map‐1) and 0.3 m/pixel (Map‐2) resolutions. The distribution and morphological characteristics of craters and rocks were analyzed, including completeness diameter, spatial density, crater type, depth/diameter ratio, and rock abundance. By recognizing and measuring concentric craters, we estimated a median regolith thickness of 1.85 m in the Map‐2 area. The relatively thin lunar regolith resulted in most craters reaching the high‐strength substrate during the cratering process, which is the primary reason for the lower depth/diameter ratio (0.116) of the fresh CE‐6 crater compared with other landing areas (e.g., 0.15 at CE‐5 landing site). Size analysis of the rocks revealed that the CE‐6 landing site has a rock abundance of 0.179%, which is close to the value (0.21%) of the CE‐4 landing site. Based on the ejecta thickness model and diffusion function, we found that the ejecta from a relatively fresh 4.7 m diameter crater is likely to be present in the uppermost layer of the sampling location. The data set generated in this study is publicly available at https://doi.org/10.5281/zenodo.14920942 .