Three Chinese Taikonauts Temporarily Left Without a Return Capsule After Debonded Rescue

Three taikonauts left without an immediate ride home after replacement capsule was used for rescue

Zhang Lu, Wu Fei and Zhang Hongzhang, the Shenzhou-21 crew, have been aboard the Tiangong space station since Oct. 31 but currently lack a dedicated, docked return vehicle after their predecessors used the replacement capsule to return to Earth following a suspected debris strike.

The Shenzhou-20 team — Wang Jie, Chen Zhongrui and Chen Dong — were originally scheduled to come home on Nov. 5 after completing a handover. At the last minute, however, observers reported that a piece of suspected orbital debris struck the Shenzhou-20 return capsule. Subsequent inspections reportedly found a crack in the capsule's viewing port, prompting mission managers to use the capsule allocated to Shenzhou-21 for the emergency return. The Shenzhou-20 crew safely splashed down on Nov. 14, after setting a taikonaut single-flight endurance record of 204 days.

That timely rescue left the Shenzhou-21 crew without their assigned return vehicle docked to Tiangong. Unconfirmed tracking and media reports suggest the China Manned Space Agency (CMSA) may launch an empty replacement return capsule, informally referred to in press reports as Shenzhou-22, possibly as early as Nov. 24. Until such a replacement arrives, however, the three crew members would have limited immediate evacuation options if another serious anomaly or debris strike occurred.

"I'm very glad that they (the Shenzhou-20 crew) got home, but it is a bit disconcerting that the replacement crew apparently does not have a vehicle to come back to Earth," said Victoria Samson of the Secure World Foundation in comments to Scientific American.

When a replacement craft reaches Tiangong, Reuters reports the damaged Shenzhou-20 return capsule will likely be detached from the station and deorbited into the Pacific Ocean. Analysts currently expect the Shenzhou-21 crew to complete their planned roughly six-month mission, but the situation highlights potential weaknesses in crew-exchange procedures and contingency planning for debris events.

Observers have suggested several possible reasons for the decision to return Shenzhou-20 before launching a fresh return vehicle: Tiangong's smaller volume (roughly one-fifth that of the International Space Station) could impose limits on accommodating six crewmembers at once, though CMSA has previously denied that capacity would prevent short-term overlap.

There is also a remote contingency: Shenzhou spacecraft consist of three separable sections — a service module, a habitation module, and a parachute-assisted reentry capsule. If the observed crack is limited to an exterior viewing port and does not compromise the primary reentry section, the damaged Shenzhou-20 capsule might still be usable in an emergency. However, without full technical disclosure from CMSA, the outside world can only speculate about the vehicle's exact condition and mission planning considerations.

The episode echoes earlier temporary "strandings" on the ISS, where crews were delayed but still had docked return vehicles available. Notable examples include extended stays by NASA astronauts Suni Williams and Butch Wilmore, and Frank Rubio, whose mission stretching beyond a year highlighted the importance of reliable return-capable spacecraft being available at all times.

What to watch next

• Verification of any CMSA announcement about a launch of an empty replacement return capsule (referred to in some reports as Shenzhou-22).
• Official technical details from CMSA on the extent and location of the damage to the Shenzhou-20 capsule.
• Any changes to Tiangong crew schedules or station operations while the contingency is resolved.

Sources cited in reporting on this developing story include Space.com, Live Science, SpaceNews, Reuters, Scientific American and Ars Technica. Because China releases limited technical detail about its missions, some operational decisions and timelines may remain unclear to outside observers.