Preparations to facilitate the return of the Shenzhou XX astronauts, whose scheduled flight to Earth was postponed due to safety concerns over space debris, are proceeding in an orderly manner, according to the China Manned Space Agency.

After a decision was made to rearrange the crew's return, mission planners and engineers promptly started following emergency response measures based on the principle of "putting the safety of astronauts first", the agency said in a statement issued on Tuesday.

Comprehensive simulation analyses, tests and safety assessments pertaining to the Shenzhou XX spaceship are being conducted to ensure every piece of hardware is in good condition and all potential risks are eliminated, it said.

Detailed steps are being formulated to facilitate the crew's safe return to Earth, it added.

Meanwhile, ground personnel at the Dongfeng landing site in northern China are performing intensive drills to prepare for the return of the astronauts, the space agency said.

"At present, the Tiangong space station is in a good state and is capable of holding two mission crews. The Shenzhou XX astronauts are living normally aboard the space station and are working with the Shenzhou XXI crew members on scientific tasks," it said.

The Shenzhou XX team, comprising mission commander Senior Colonel Chen Dong and crew members Colonel Chen Zhongrui and Colonel Wang Jie, was originally scheduled to fly back on Nov 5 after staying at the space station for six months.

They represent China's 15th manned spaceflight and comprise the ninth group of residents aboard the Tiangong, which is currently the only operational space station independently run by a single nation.

Their return was deferred to an unspecified date after it came to light that the Shenzhou XX spaceship had possibly been hit by tiny pieces of space debris.

Such debris includes everything from spent rocket stages and old satellites to fragments from disintegration, erosion and collisions, and even paint flecks. Some pieces of debris may collide with operational spacecraft or cause hazards to manned spaceflights.

zhaolei@chinadaily.com.cn