A pair of Chinese taikonauts have completed an eight-hour spacewalk repairing damage to the Tiangong Chinese Space Station’s solar panels. It’s believed the damage was caused by tiny pieces of space debris, which impacted the solar wings and degraded their function. They performed a first repair spacewalk in December 2023 and completed the repairs with their second trip outside in March 2024. The Shenzhou 17 crew were the sixth group living in Tiangong and were relieved by the Shenzhou-18 team in late April.
The Shenzhou-18 mission, launched prior to the conclusion of Shenzhou-17, will last approximately six months. The crew, consisting of Ye Guangfu, Li Cong, and Li Guangsu, launched from the Jiuquan Satellite Launch Center aboard a Long March 2F rocket at 20h59 Beijing Time. Their spacecraft docked with the station’s Tianhe core module approximately six and a half hours after liftoff. On May 28, 2024, Ye Guangfu and Li Guangsu executed China’s longest spacewalk to date, lasting eight and a half hours, installing a space debris protection device on the station.
Senior Colonel Tang Hongbo and Lieutenant Colonel Jiang Xinlin completed nearly eight hours of extravehicular activity to repair damage to the Tianhe core module’s solar wings caused by impacts from tiny space debris. Lieutenant Colonel Tang Shengjie provided internal support throughout the operation, which marked the first instance of such a repair by Chinese taikonauts. This event, the 15th spacewalk conducted by Chinese astronauts, underscores the critical nature of maintaining the station’s integrity and safety. These operations are complex, but vital and require precise coordination and planning between the astronauts and ground control.
Although the term “spacewalk” is commonly used, the official term for when an astronaut ventures outside a spacecraft is Extravehicular Activity (EVA). The definition of an EVA can vary depending on the country conducting the operation. For instance, Russian and Soviet spacecraft designates an EVA as any instance where a cosmonaut spends time in a vacuum while in a space suit, using specialized airlocks for this purpose. In contrast, the American definition requires at least the astronaut’s head to be outside the spacecraft. Regardless of the definition, an EVA involves leaving the protective environment of the spacecraft and entering outer space, the area outside of Earth’s atmosphere. China made history as the third country to independently perform an Extravehicular Activity (EVA) on September 27, 2008, during the Shenzhou-7 mission. During this mission, Chinese taikonaut Zhai Zhigang completed a 22-minute spacewalk, fully exiting the spacecraft while wearing the Chinese-developed Feitian space suit. Taikonaut Liu Boming, dressed in the Russian-derived Orlan space suit, assisted Zhai by standing by at the airlock and straddling the portal.
The vacuum of space presents significant dangers due to its near complete lack of gas pressure. On Earth, our atmosphere, a mix of nitrogen, oxygen, and hydrogen gases, exerts a pressure of about 101 kilopascals at sea level, which our bodies are accustomed to. In space, however, the absence of pressure means that without a proper space suit, the air in an astronaut’s lungs would rapidly escape, and gases in body fluids would expand, causing severe internal damage. Additionally, astronauts face extreme temperatures, with sunlit objects reaching over 248 degrees Fahrenheit (120 degrees Celsius) and shaded areas dropping below negative 212 degrees Fahrenheit (negative 100 degrees Celsius). Furthermore, radiation from the sun, ultraviolet rays, and tiny meteoroids pose additional hazards.
To mitigate these risks, space suits are designed to maintain life support in the vacuum of space while allowing for sufficient mobility to perform tasks. These suits are essential for EVAs, providing the necessary protection against the harsh conditions of outer space. This advanced technology enables astronauts like those from the Shenzhou-17 crew to conduct critical repair operations and scientific experiments, ensuring the continued functionality and safety of missions aboard the Tiangong space station.
Since 2021, China has significantly advanced its space capabilities by conducting numerous extravehicular activities, each lasting several hours. These EVAs have been crucial for the construction and maintenance of the Tiangong space station.
During their time on the station, the Shenzhou-17 crew continued with planned space science experiments, technical tests, planned maintenance, and the installation of extravehicular payloads. Their tenure concluded with a handover to the incoming Shenzhou- 18 crew, ensuring the continuous operation of the Tiangong space station.
The recent repair and continued maintenance operations by both crews not only demonstrate China’s growing expertise in manned spaceflight but also highlight the collaborative and technical challenges of sustaining life and functionality in the harsh environment of space. The Tiangong space station is an important platform for research and technological advancement. The dedication of the Shenzhou crews, and the ongoing operational improvements in orbit pave the way for long term and sustained human activities far beyond our atmosphere.