Chen Dong and Liu Yang complete the 5th spacewalk for Tiangong Space Station
At 16:33 UTC on September 1, 2022, 00:33 Beijing time, after about 6 hours of outboard activities, Shenzhou 14 astronauts worked closely together to complete all the scheduled tasks during the outboard activities. He has returned to the Wentian experimental cabin safely, and the Extra Vehicular activity was a complete success.
The 5th Spacewalk of Tiangong Space Station began at 18:26 on September 1, 2022, Beijing time (12:26 UTC), Mission commander of Shenzhou-14 Chen Dong and crew member Liu Yang were assigned to conduct the spacewalk mission this time, while their teammate Cai Xuzhe was responsible for various support work inside the cabin,
Chen Dong donned the Feitian spacesuit and successfully opened the exit hatch of the Wentian experimental cabin airlock at 19:09 (13:09 UTC).
During the astronaut's Extra Vehicular activities, the station and earth cooperated closely, and the inside and outside of the cabin cooperated closely, and successively completed tasks such as the installation of the extended pump set in the Wentian cabin, the lifting of the panoramic camera in the Wentian cabin, and the autonomous emergency return verification outside the cabin. The whole process was smooth and successful.
The inspection and ability of the astronauts to work together with the small robotic arm have been verified, and the functional performance of the Wentian experimental cabin airlock and related support equipment for exit activities has been verified.
Unlike previous times when the Shenzhou-12 and 13 crews exited the space station through the Tianhe core cabin, the Shenzhou-14 crew for the first time ventured out through the airlock cabin in the Wentian lab module, which just arrived at the space station on July 25.
The node cabin for the astronauts' exit in the Tianhe has a hatch width of 85 centimeters, while the airlock cabin in the Wentian is one meter wide, allowing astronauts with space suits on and equipment in hand to walk more "freely" into space, developer and manufacturer of the cabin the China Academy of Space Technology (CAST)
Therefore, the airlock cabin of the Wentian will become the main exit-entry point for extravehicular activities, while the previous one in the Tianhe will serve as backup. The two exit-entry cabins will greatly boost the reliability and better ensure the safety of astronauts in case of an emergency during extravehicular work, according to Li Jinlin, a chief designer of extravehicular suits at the Astronaut System at the China Manned Space Agency.
Exiting from the Wentian lab module instead of the Tianhe means that the astronauts must take different routes and that requires a number of technical adjustments, Wang Ya'nan, chief editor of Beijing-based Aerospace Knowledge magazine, said. The successful mission has verified the feasibility of using the Wentian as the main exit-entry hatch.
Thursday's mission also verified the functions of the five-meter-long small robotic arm installed outside the airlock cabin. With seven degrees of freedom, the set has a higher precision and flexibility to "grasp" small and medium-sized pieces of equipment, and is capable of more delicate operations than the bigger robotic arm with the Tianhe module.
During the construction stage of the space station, astronauts have to complete equipment installation, maintenance, and other tasks outside the cabin. With a greater range of movement needed for a more challenging extravehicular activity, safety requirements have also become more stringent.
Therefore, research teams have developed a longer and retractable safety rope, allowing more than 10 meters of connection between the astronauts and the module. This will not only pose little interference to spacesuits or the movement of the astronauts but will also withstand the test of the space environment with a 200 C temperature gap, space irradiation, and other harsh conditions, the CAST noted.
Over more than three years, ground research teams have independently developed 238 outboard maintenance tools in 36 categories for the core module and the Wentian lab module, with a total weight of 509 kilograms, it added.
China has been making steady progress in planning extravehicular activities. The first batch of astronauts entering the Tianhe, the Shenzhou-12 crew, carried out one spacewalk mission, while for their successor, the Shenzhou-13 crew, two missions were successfully completed. The Shenzhou-14 squad is expected to conduct two to three spacewalk missions.
Experts said that compared with previous times, which were more focused on technology verification, Shenzhou-14's extravehicular activities are more task-oriented.
With extravehicular activity becoming more regular, related technologies have also become more mature. The Shenzhou-12 and -13 missions were mainly for technical verification but now with the Shenzhou-14, these technologies will enter the application stage, as our Wentian module has arrived, and a lot of basic work needs to be done. Song Zhongping, a TV commentator who closely follows China's space program.
"Meanwhile, a large amount of preparation work is also needed for the upcoming Mengtian launch and docking, so now we are following the actual needs of building the space station to arrange extravehicular activities, and that's very different from the previous mission," Song said.
Since they arrived at China's space station on June 5, the three crew members of Shenzhou-14 have spent 88 days in orbit. They have completed multiple tasks including the transfer of materials from the cargo spacecraft, in-orbit testing of the Wentian lab module, unlocking the science experiment cabinets, functional tests of the small robotic arm, and the management of the space station assembly, according to the CMSA.