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 Center 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 9:22 am (0122 GMT) 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. 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.
The Tianhe builds on experience China gained from operating two experimental space stations earlier in its increasingly ambitious space program. Chinese astronauts spent 33 days living on the second of the previous stations, carried out a spacewalk and taught science classes that were beamed down to students across the country.
China landed a probe, the Tianwen-1, on Mars last month that carried a rover, the Zhurong. It also has brought back lunar samples, the first by any country’s space program since the 1970s, and landed a probe and rover on the moon’s less explored far side.
Beijing doesn’t participate in the International Space Station, largely due to US concerns over the Chinese program’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.