Analysis of Illumination Conditions in the Lunar South Polar Region Using Multi-Temporal High-Resolution Orbital Images

• Published in: Remote Sensing
• Main Authors: Yifan Zhang, Bin Liu, Kaichang Di, Shaoran Liu, Zongyu Yue, Shaojin Han, Jia Wang, Wenhui Wan, Bin Xie
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2023
• Subjects: moon; south polar region; Chang’E-7; illumination conditions; multi-temporal high-resolution orbital images; Science; Q; South Pole; South pole
• Online Access: https://doi.org/10.3390/rs15245691; https://doaj.org/article/5e410940b6524860b5b9b6efdf93dea7

The illumination conditions of the lunar south pole region are complex due to the rugged terrain and very low solar elevation angles, posing significant challenges to the safety of lunar landing and rover explorations. High-spatial and temporal-resolution analyses of the illumination conditions in the south pole region are essential to support mission planning and surface operations. This paper proposes a method for illumination condition analysis in the lunar pole region using multi-temporal high-resolution orbital images with a pre-selected landing area of Chang’E-7 as the study area. Firstly, a database of historical multi-temporal high-resolution (0.69–1.97 m/pixel) orbital images, with associated image acquisition time, solar elevation angle, and azimuth angle, is established after preprocessing and registration. Secondly, images with the nearest solar elevation and azimuth at the planned time for mission operations are retrieved from the database for subsequent illumination condition analysis and exploration support. The differences in the actual solar positions at the mission moments from that of the nearest sun position image are calculated and their impact on illumination conditions is evaluated. Experimental results of the study area demonstrate that the constructed image database and the proposed illumination analysis method using multi-temporal images, with the assistance of DEM in a small number of cases, can effectively support the mission planning and operations for the Chang’E-7 mission in the near future.