China will launch a spacecraft carrying three astronauts on a scheduled flight to the core module of the unfinished Chinese space station, where they will work and live for six months.
China is preparing to launch a three-person mission to complete work on its permanent orbiting space station.
China Manned Space Agency said its spaceship is due to blast off from the Jiuquan Satellite Launch Centre on the edge of the Gobi Desert on Sunday morning at around 10:44 am local time (0244 GMT).
The Shenzhou-14 crew will spend six months on the Tiangong station, during which they will oversee the addition of two laboratory modules to join the main Tianhe living space that was launched in April 2021.
Commander Chen Dong and fellow astronauts Liu Yang and Cai Xuzhe will assemble the three-module structure joining the existing Tianhe with Wentian and Mengtian, due to arrive in July and October.
"All preparations for the launch are basically ready," said Lin Xiqiang, an agency official.
Another cargo craft, the Tianzhou-3, remains docked with the station.
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China’s space programme
China’s space programme launched its first astronaut into orbit in 2003, making China only the third country to do so on its own after the former Soviet Union and the US.
It has landed robot rovers on the moon and placed one on Mars last year. China has also returned lunar samples and officials have discussed a possible crewed mission to the moon.
China's space programme is run by the ruling Communist Party's military wing, the People's Liberation Army, prompting the US to exclude it from the International Space Station.
Chen, Liu and Cai will be joined at the end of their mission for three to five days by the crew of the upcoming Shenzhou 15, marking the first time the station will have had six people aboard.
The space station will have a designed lifespan of a decade. At 180 tonnes, it will be slightly heavier than Russia's decommissioned Mir, and about 20 percent of the International Space Station by mass.
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