Tang Hongbo, Nie Haisheng and Liu Boming are expected to set foot on Earth again soon.
The three Chinese astronauts completed this Thursday a record three-month mission in space, on the construction site of the Chinese space station (CSS), also called Tiangong, announced the news agency China news.
The three men had left Earth in June aboard the Shenzhou-12 spacecraft.
Their 90-day mission is the longest ever carried out in space by Chinese astronauts, the official news agency said, without specifying when their return to Earth is expected.
According to New China, the vessel separated from the Tiangong station to which it had been docked for three months at 8:56 a.m. Beijing time (0:56 a.m. GMT).
On site, the three astronauts tested the station's equipment, carried out scientific experiments, raised public awareness and monitored their health, according to the details of the mission described in June New China.
2022 target for CSS
Before them, eleven Chinese, men and women, left for space.
From now on, the presence of taikonauts on board the final station should be continuous from spring 2022. It is also during the year 2022 that the CSS must be completed, after sending two laboratories.
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In a context of tension with the West, the success of the mission is a matter of prestige for Beijing, which on July 1 celebrated the centenary of the Chinese Communist Party (CCP).
The Chinese space station, when completed, will be similar in size to the former Soviet Mir station (1986-2001).
Its lifespan will be at least ten years.
China resolved to build its own space station after the United States refused to let it participate in the ISS, the international space station.
The latter - which brings together the United States, Russia, Canada, Europe and Japan - is due to retire in 2024, even though NASA has mentioned a possible extension beyond 2028.