Three astronauts are stuck on China’s space station without a safe ride home

Spacecraft swapping in low Earth orbit

With their original spacecraft deemed unsafe, Chen and his companions returned to Earth aboard the new Shenzhou 21 spacecraft, which launched and arrived at Tiangong Station on October 31. The three astronauts who launched Shenzhou 21-Zhang Lu, Wu Fei, and Zhang Hongzhang-Stay aboard the nearly 100-metric-ton space station and have only the damaged Shenzhou 20 spacecraft available to bring them home.

China’s Shenzhou spacecraft not only provide transportation to and from low Earth orbit, but they also serve as lifeboats to evacuate astronauts from the Chinese space station in case of in-flight emergencies, such as major failures or medical crises. They serve a similar role to the Russian Soyuz and SpaceX Crew Dragon vehicles that fly from the International Space Station.

Another Shenzhou spacecraft, Shenzhou 22, “will be launched at a later date,” the China Manned Space Agency said in a statement. Shenzhou 20 will remain in orbit to “continue relevant experiments.” The Tiangong Laboratory is designed to support a crew of six for only short periods of time, with facilities for three astronauts for longer periods of stay.

Officials have not disclosed when Shenzhou 22 might launch, but Chinese officials usually have the Long March rocket and Shenzhou spacecraft on standby for a rapid launch if needed. Instead of astronauts, Shenzhou 22 will bring fresh food and equipment to maintain the three-man crew at Tiangong Station.

China’s state-run Xinhua news agency called Friday’s homecoming “the first successful implementation of the alternative return procedure in the history of the country’s space station program.”

The rescheduled return to Tiangong Station and the damaged spacecraft are a reminder of the risks of space junk, especially small pieces of debris that go undetected by tracking telescopes and radar. A small piece of space debris traveling at several miles per second can pack a punch. Tiangong outpost personnel went outside the station several times over the past few years to install a space debris shield to protect the outpost.

Shortly after landing on Friday, ground teams assisted the Shenzhou astronauts out of their landing module. The trio appeared to be in good health and cheerful after completing the longest-duration crewed mission in the history of China’s space program.

“Space exploration has never been easy for mankind,” mission commander Chen Dong said, according to Chinese state media.

“This mission was a true test and we are proud to have successfully completed it,” Chen said shortly after landing. “China’s space program has stood the test, all teams have performed excellently… This experience has deeply impressed upon us that the safety of astronauts is indeed a priority.”