Astronauts Chen Dong, Chen Zhongrui and Wang Jie attend a see-off ceremony on April 24 for the Shenzhou-20 spaceflight mission at Jiuquan Satellite Launch Center near Jiuquan, Gansu province, China.
A Long March-2F rocket carrying the Shenzhou-20 spacecraft takes off April 24 from the Jiuquan Satellite Launch Center for a crewed mission to China's Tiangong space station.

Three Chinese astronauts have returned to Earth after they were briefly stranded at the nation's space station when space debris struck the vehicle they were meant to travel aboard.

The delay may remind some of the unexpected lengthy stay two NASA astronauts recently experienced when they reached the International Space Station in June 2024 aboard the Boeing Starliner capsule. But while NASA's Butch Wilmore and Suni Williams remained at the space station for 286 days, China's spacefarers remained stuck in orbit for just nine days beyond their mission's scheduled end.

The crew departed China's Tiangong space station on another spacecraft, landing Friday in northern China, the nation's human spaceflight agency announced.

The situation also highlights the growing threat that space debris, also called space junk, poses to spacefarers and key orbital infrastructure.

Here's everything to know about the Chinese astronauts who returned to Earth after being stranded in space.

Astronauts stranded at Tiangong space station after space debris strike

The astronauts – Chen Dong, Chen Zhongrui and Wang Jie – were due to return Nov. 5 to Earth after completing a six-month mission on China's Tiangong space station.

But tiny chunks of space debris reportedly struck the crew's return vehicle before they were able to depart.

The China Manned Space Agency (CMSA), which investigated the incident, said Friday, Nov. 14, that "tiny cracks" were found in a small window of the Shenzhou-20 spacecraft's return capsule, Reuters reported.

"The capsule does not meet the safety requirements for a crewed return, Shenzhou-20 will remain in orbit and conduct relevant experiments," the agency said in a statement quoted by Reuters.

3 Chinese astronauts return to Earth

In line with existing protocols, the astronauts returned to China aboard the vessel their replacements crewed to the Tiangong space station.

The crew departed Tiangong on the Shenzhou-21 spacecraft, according to CMSA, touching down at the Dongfeng landing site in north China's Inner Mongolia Autonomous Region at 4:40 p.m. local time, or 3:40 a.m. ET.

Shenzhou-20 mission launched in April

The spacecraft hit by the space junk was the Shenzhou-20 capsule, which in April transported the crew of three astronauts to the space station. The mission is part of China's Shenzhou program, which takes trios of Chinese astronauts to and from Tiangong for six-month stays, where they perform a variety of tasks.

The mission's replacements, part of the Shenzhou-21 mission, docked with the station Saturday, Nov. 1. The crews of both vessels were in the midst of a handover period as the new arrivals spent a few days familiarizing themselves with the outpost before the Shenzhou-20 was to depart Wednesday, Nov. 5.

Now that the Shenzhou-20 astronauts have departed on the Shenzhou-21 vehicle, the Shenzhou-21 crew now find themselves in need of a replacement spacecraft for their own voyage home. A backup Shenzhou spacecraft will be sent from the Jiuquan Satellite Launch Centre in northwest China at "an appropriate time in the future," Reuters reported.

What is Tiangong? What to know about China's space station

Because China is not among the partners on the International Space Station, the nation operates its own outpost in orbit.

Named Tiangong, the three-module space station became fully operational in 2022 in low-Earth orbit, according to the nonprofit Planetary Society.

China plans to expand Tiangong in the coming years by adding more modules, along with plans to launch a space telescope similar to NASA's Hubble that will orbit nearby and be able to dock for repairs.

Contributing: Reuters

Eric Lagatta is the Space Connect reporter for the USA TODAY Network. Reach him at elagatta@gannett.com

This article originally appeared on USA TODAY: 3 Chinese astronauts return to Earth after space junk strands them in orbit

Reporting by Eric Lagatta, USA TODAY / USA TODAY

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