The Shenzhou-14 is the first and will be the toughest manned mission during the construction of China's space station and has great significance, according to Huang Weifen, chief astronaut system designer of the China Manned Space Program.

Huang said that the crew – Chen Dong, Liu Yang and Cai Xuzhe – all selected from the second cohort of Chinese astronauts, are the most suitable.

"The three are all very diligent and careful and they have great team spirit and friendship among them," she said.

Huang told CGTN reporter Zheng Yibing that the crew received intensive training in more than 100 subjects in eight categories before their mission.

She unveiled the details of the Shenzhou-14 mission, saying that the three astronauts will test nine different formations for the assembly of the space station, will change the capsule position twice, and conduct five dockings and three separations and evacuations.

The chief astronaut system designer said that the crew will do two to three space walks using a combination of the airlock module, and big and small robot arms.

"They will for the first time enter the Wentian and the Mengtian space labs to unlock and test more than a dozen experimental boxes and many others," Huang said.

During their six-month stay, the trio will welcome the two lab modules, Wentian in July and Mengtian in October, and then the Tianzhou-5 cargo spacecraft. They will also rotate with the crew of the Shenzhou-15 manned spaceship in orbit before returning to Earth in December 2022.

She also praised the previous Shenzhou-12 and -13 missions, saying the crews are in very good condition. 

"Their excellent performances in orbit proved our effectiveness in selecting, training, and helping astronauts stay in space for a long time," said Huang, who earlier this year released the information that the Shenzhou-14 and -15 crews will live and work together in China's space station for a short period.

When asked about when international astronauts could join the missions at the China Space Station, the chief designer said that China has long been working with others, for example, the European Astronaut Centre, in selecting and training, medical monitoring and support and space foods.

"So, we've been making relevant technical preparations and discussing how we should select and train," she said.

"And many other countries, for example Pakistan, expressed willingness to join flight missions on the China Space Station. I believe there will certainly be a time for international astronauts to come," Huang Weifen said.

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