China is set to send the first three crew members to its new space station on Thursday morning.
Two of the astronauts flew in previous missions while the third is going to space for the first time, China Manned Space Agency Assistant Director Ji Qiming told reporters at the Jiuquan Satellite Launch Centre in northwestern China on Wednesday.
The main section of the Tianhe, or Heavenly Harmony, station was launched into orbit on April 29.
The three men heading to the space station on Thursday plan to live there for three months, conducting spacewalks, maintenance work and science experiments.
The astronauts will be traveling in the Shenzhou-12 spaceship launched by a Long March-2F Y12 rocket set to blast off at 9.22am local time (2.22am UK time) on Thursday.
The mission would be the third of 11 that are planned through the end of next year to build and maintain the station and send up crew members and supplies, and the station’s other two modules are due to be launched next year.
It is the first crewed Chinese mission in five years.
China has sent 11 astronauts into space since becoming only the third country to do so in 2003, all of them pilots from the ruling Communist Party’s military wing, the People’s Liberation Army.
Though the first Tianhe crew will be all male, women will be part of future crews on the station, officials have said.
Beijing does not participate in the International Space Station (ISS), largely due to US concerns over the Chinese programme’s secrecy and its military connections.
Despite that, foreign science missions and possibly foreign astronauts are expected to visit the Chinese station in future.
Once completed, the Tianhe will allow for stays of up to six months, similar to the much larger International Space Station.
The Chinese station reportedly is intended to be used for 15 years and may outlast ISS, which is nearing the end of its functional lifespan.
The launch of Tianhe was considered a success although China was criticised for allowing the uncontrolled re-entry to Earth of part of the rocket that carried it into space. Usually, discarded rocket stages re-enter the atmosphere soon after lift-off, normally over water, and don’t go into orbit.
The rocket blasting off on Thursday is of a different type, and Ji dismissed concerns about it or the models used for cargo missions posing a threat when they re-enter. China published their trajectories and they are expected to burn up long before they could be a danger, he said.