According to the National Space Administration, at 6:23 am on June 2nd, the Chang'e-6 lander and ascent combination (hereinafter referred to as the "combination") successfully landed in the pre selected landing area of the South Pole Aitken Basin on the far side of the Moon with the support of the Queqiao 2 relay satellite. At 6:9 pm on the same day, the combination began to implement a power descent, and the 7500 Nm variable thrust main engine started. During this time, the combination underwent rapid posture adjustments and gradually approached the lunar surface. Afterwards, automatic obstacle detection is carried out through a visual autonomous obstacle avoidance system. A visible light camera is used to select a rough safety point based on the brightness of the moon, hover 100 meters above the safety point, and use laser 3D scanning for precise photography to detect lunar obstacles. Finally, the landing point is selected, and the engine is turned off when it is about to reach the moon. The buffer system is used to ensure that the combination reaches the moon in a free fall manner, and finally lands smoothly. The reporter learned from the Fifth Academy of China Aerospace Science and Technology Corporation that the Chang'e-6 lunar landing mission is the fifth soft landing of extraterrestrial celestial bodies, the fourth soft landing on the lunar surface, and the second soft landing on the lunar back implemented by China. The hospital's multiple "hardcore technologies" have supported the successful implementation of this lunar landing mission. The location selection of the lunar backside land area faces new challenges. The mission goal of Chang'e-6 is to achieve the first automatic sampling and return of the lunar backside by humans. The selection of the landing area is directly related to the risk control of engineering implementation and the scientific output of sampling samples. Compared to the front of the moon, the terrain on the far side of the moon is more rugged, especially in the Antarctic Aitken Basin area on the far side of the moon where the overall terrain is lower and there are more impact craters distributed, making lighting and measurement more susceptible to terrain obstruction. These factors have posed challenges to the site selection work for the Chang'e-6 lunar landing. In order to ensure the stable landing of Chang'e-6 on the lunar back, the research and development team of the Fifth Academy conducted in-depth discussions and analysis on the site selection difficulties and characteristics of the lunar back sampling task, fully drawing on the site selection experience of previous models of deep space exploration, and establishing a set of site selection methods suitable for lunar back landing. Using remote sensing data from previous models, the development team conducted in-depth analysis and confirmation of the complex terrain and landforms in the land area, in order to find areas on the lunar surface that meet the needs of safe landing, lunar work, and lunar takeoff for the combination. After confirming the landing area, the development team conducted multiple rounds of review and research on the terrain, geological conditions, etc. of the land area, further reducing landing risks, ensuring complete analysis of the site selection area, comprehensive consideration of site selection constraints, and reliable and usable site selection results. The GNC system independently implements "coarse and fine relay obstacle avoidance". This Chang'e-6 lunar landing mission fully draws on the successful experience of multiple soft landings of extraterrestrial celestial bodies in China, once again demonstrating China's unique "coarse and fine relay obstacle avoidance" technology. The GNC (Guided Navigation and Control) system used by the Chang'e family was developed by the 502 Institute of the Fifth Academy of Engineering. The system needs to know in real-time where I am, where I am going, and how I am going. It is like a pilot during the process of landing on the moon, responsible for completing three core tasks: flight trajectory control, safe landing point selection, and precise control. During the descent process, the Chang'e-6 GNC system needs to autonomously select a landing point that meets both landing requirements and lunar takeoff conditions for the ascent, creating favorable conditions for subsequent soil retrieval and takeoff. For this purpose, the GNC system will autonomously control the combination body to quickly adjust its posture while landing, take photos and analyze the predetermined landing area, and fly towards the selected area. This is the first obstacle avoidance, also known as "rough obstacle avoidance". When closer to the lunar surface, the combination performs a brief hover, takes another photo of the lunar surface, accurately avoids obstacles, and selects the final landing point. This is the second obstacle avoidance, also known as "precise obstacle avoidance". Afterwards, the combination drifts directly above the landing point and descends vertically. When reaching a specific height, the main engine is turned off and a soft landing is achieved using the landing leg's cushioning mechanism. Compared to Chang'e-5, Chang'e-6 consumes more propellant, and researchers have made targeted adjustments, optimizations, and upgrades to the GNC system to ensure lunar landing accuracy while also considering the economic use of resources. Parking radar makes landing more precise. The lunar landing process can be said to be intertwined and full of dangers. The support of distance and speed information is an important factor in determining the success or failure of the mission. The microwave ranging and velocity sensor developed by the Xi'an branch of the Fifth Academy of Sciences is like a "parking radar" installed on the Chang'e-6 lander. It starts working as the lander approaches the lunar surface, meticulously measuring various data and accurately transmitting them, allowing the lander to accurately determine the landing point and landing speed, providing reliable guarantees for safe and accurate landing. To cope with the impact of the landing moment, Factory 529 of the Fifth Academy of Engineering has customized four lightweight and high-strength landing legs for the lander, commonly known as the landing buffer mechanism. Each landing leg consists of one main leg, two auxiliary legs, and one foot pad, which work together to make it safer and more comfortable for Chang'e-6 to land on the moon. The reporter learned from the National Space Administration that the payload carried by the Chang'e-6 lander will continue to work as planned and carry out scientific exploration missions. The international payload of the Chang'e-6 mission, the China Europe Space Agency lunar surface negative ion analyzer and the French lunar radon detector, are about to start operation, and the Italian laser corner reflector has been deployed. It is reported that after the successful landing of the combination, the lander will conduct status checks and settings such as the deployment of solar wings and directional antennas under ground control through the Magpie Bridge 2 relay satellite. After that, the lunar backsampling work will officially begin for about 2 days. Lunar soil samples and lunar surface rocks will be collected separately through drilling tools and mechanical arm surface sampling, achieving multi-point and diversified automatic sampling. At the same time, on-site investigation and analysis of the landing area on the far side of the moon, analysis of lunar soil structure, and other scientific explorations will be carried out to deepen research on the genesis and evolutionary history of the moon. (Lai Xin She)