Core Viewpoint - The article commemorates the life and contributions of Du Heng, a pioneer in China's space environment and space debris protection field, who passed away on November 24, 2025, at the age of 90 [1][3]. Group 1: Personal Background - Du Heng was born in March 1935 in Shanghai and enrolled in Peking University in 1954, majoring in geophysics, later transitioning to space physics [3]. - He graduated with a master's degree in 1965 and worked at the Chinese Academy of Sciences National Space Science Center from 1965 to 1995, focusing on space physics and environmental research [3]. Group 2: Contributions to Space Research - Du Heng was a key founder of China's space environment research, leading over ten national projects, including the "863" program [3][4]. - He played a significant role during the "Two Bombs, One Satellite" project, conducting research on high-altitude nuclear explosions and missile-related physics, laying a foundation for national defense technology [3]. - In 1966, he led radiation protection research for the "Dongfanghong-1" satellite, making it one of the first satellites globally to consider radiation protection [3]. - He was responsible for the first top-level design report on space environment in China, completed in 1989, and led the development of several balloon satellites and the "Shijian-4" satellite [3][4]. Group 3: Space Debris Research - Du Heng was a foundational figure in China's space debris research, initiating it as a specialized research direction in 1987 during the "863" program [4]. - In 2000, he became the first head of the National Defense Science and Technology Commission's Space Debris Action Plan Expert Group, establishing a systematic and forward-looking framework for space debris research [4]. - His proposed three major engineering development goals for space debris in 2005 became a milestone core program, providing a clear direction for the long-term development of this field in China [4]. Group 4: Legacy and Recognition - Du Heng was recognized for his loyalty to the country and the Party, innovative spirit, and dedication to advancing China's aerospace industry [4]. - His contributions were significant in the development of China's first artificial Earth satellite and manned spaceflight missions [4].

Core Points - The Shenzhou-20 astronaut team successfully completed their second extravehicular activity (EVA) lasting approximately 6.5 hours [1][9] - The installation of an automatic foot limit adapter and interface connector was a key task, which is expected to reduce future EVA times by about 40 minutes [5][7] - The team also installed a space debris protection device and conducted inspections of external equipment during the EVA [9][16] Group 1 - The Shenzhou-20 mission has been ongoing for over two months, focusing on various space science experiments [13] - The space debris issue has become increasingly prominent due to the rise in human space activities, posing risks to the space station [14][16] - The Chinese space station has improved its collision warning and avoidance processes to enhance its ability to prevent collisions [16][18] Group 2 - The Shenzhou-20 mission has completed a total of seven installations of space debris protection devices, providing reinforcement for critical components of the space station [16] - The research team has developed a monitoring and positioning system for potential leaks due to impacts, increasing the astronauts' response time to emergencies [18] - International cooperation has been established to share information and maintain the safety of spacecraft in orbit [18]