The return capsule of the Shenzhou-21 spaceship, carrying the Shenzhou-20 astronauts Chen Dong, Chen Zhongrui and Wang Jie, touched down at the Dongfeng landing site in north China's Inner Mongolia Autonomous Region on Friday.

The team left their Shenzhou-20 spacecraft in orbit and came back using the recently arrived Shenzhou-21 that had ferried a three-person replacement crew to the station, the China Manned Space Agency (CMSA) said.

It wasn’t clear if the change in spacecraft would affect the timing of future missions to the Tiangong space station.

The CMSA has not specified when Shenzhou-22 would be launched.

The return capsule deployed a red and white striped parachute before coming down in the late afternoon at a remote site in the Gobi Desert, about five-and-a-half hours after leaving the space station.

The three Shenzhou-20 astronauts had been on a six-month rotation and were originally scheduled to return on November 5, four days after the new crew arrived.

Their return was delayed for nine days. The original return plan was scrapped because a window in the Shenzhou-20 return capsule had tiny cracks, most likely caused by impact from space debris.

There are millions of pieces of mostly tiny debris circling the Earth at speeds faster than a bullet flies. They can come from launches and collisions and pose a risk to satellites, space stations and the astronauts who operate outside them.

The temporarily stranded astronauts, who had travelled to the space station in April, conducted experiments with the new crew and were "in good condition, working and living normally,” the agency has said this week.

The latest mission brought four mice to study how weightlessness and confinement would affect them. The study will help master key technologies for breeding and monitoring small mammals in space, an engineer from the Chinese Academy of Sciences said. (Xinhua/Reuters)