Three Chinese astronauts are currently stranded aboard the Tiangong space station after their designated return vehicle was damaged by space debris earlier this month. The crew of the Shenzhou 21 mission – Zhang Lu, Wu Fei, and Zhang Hongzhang – remains in orbit while Chinese authorities prepare a replacement spacecraft for launch on November 25.
Damage and Response
The incident occurred when a small piece of orbital debris collided with the return craft, cracking its viewing port. The China Manned Space Agency (CMSA) confirmed the damage but has released limited details about the extent of the impact.
While CMSA is working to launch a replacement vehicle, the astronauts will remain aboard Tiangong until then. A key question remains: why the entire six-person crew (including the returning astronauts from the previous mission) was not kept on the station until a safe return craft was secured, given that supplies would have been limited.
Increased Risk in Low Earth Orbit
This event highlights the growing threat of space debris in low Earth orbit. In 2021, the International Space Station (ISS) suffered damage from a debris strike, and the ISS has had to maneuver to avoid collisions with space junk on multiple occasions. The increasing congestion of orbital space elevates the risk of future incidents, potentially endangering both crewed and uncrewed missions.
Precedent and Expert Concerns
This is not the first recent case of astronauts facing extended stays in orbit due to technical issues. Earlier this year, NASA astronauts Butch Wilmore and Suni Williams spent nine months in orbit instead of the planned eight days after their return craft malfunctioned.
Jan Osburg, a senior engineer at the RAND Corporation, described the situation as “a massive wake-up call,” emphasizing the growing vulnerability of space missions to orbital debris.
The world now awaits the successful launch and docking of the replacement spacecraft, bringing the stranded astronauts safely back to Earth. The incident underscores the need for more robust space debris mitigation efforts to ensure the long-term sustainability of space exploration.
