The Shenzhou-20 mission has delayed its mission to Earth while damage to the return capsule is assessed

The return of three Chinese astronauts back to Earth from the Tiangong space station has been delayed after their spacecraft was reportedly damaged by debris.

The Shenzhou-20 crew - led by commander Chen Dong, a veteran astronaut and former Chinese fighter pilot, Chen Zhongrui, and Wang Jie - were scheduled to depart the station and land in Inner Mongolia on Wednesday. However, the China Manned Space Agency (CMSA) announced the cancellation in a brief online statement, instructing the trio to remain aboard. The astronauts have been in orbit since launching on April 24.

The agency said the spacecraft is "suspected of being struck by small space debris" and is conducting an impact analysis, declining to provide a new return timeline.

The CMSA did not detail the circumstances of the suspected impact or mention the presence of the Shenzhou-21 craft, which docked with Tiangong last week for a planned crew handover. Under standard spaceflight protocols, if a return vehicle is deemed unsafe, a backup spacecraft such as Shenzhou-21 can be used to bring astronauts home.

The Shenzhou program is tasked with ferrying crews to and from Tiangong for six-month rotations, during which astronauts conduct scientific experiments and perform station maintenance.

The Shenzhou-20 astronauts conducted four spacewalks during their mission outside the Tiangong space station to install debris shields and other external equipment, according to official reports from China.

The incident underscores the growing threat that space debris poses to orbital activities. Space junk, consisting of defunct satellites, spent rocket stages, and other fragments, orbits the Earth at high speeds, creating a collision risk for vital space station modules and other spacecraft.

While a prior Shenzhou mission was delayed by adverse weather, the current situation marks the first time a Chinese crewed return has been postponed due to a suspected debris strike.

The incident echoes other recent mission extensions. Technical issues with a Boeing Starliner last year forced two NASA astronauts to remain at the International Space Station for nine months before they could secure a ride home on a different vessel.