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What kind of person can be deemed as qualified to become a crew member of Shenzhou-11? And why were only two astronauts chosen for the mission this time?

50-year-old Jing Haipeng and 38-year-old Chen Dong were given the honors of conducting China's sixth manned spaceflight mission, Shenzhou-11.

Huang Weifen, deputy chief designer at the China Astronaut Center, says not only the astronauts' technical skills play a significant role for a great mission. The interpersonal coordination also means a lot.

So in the astronauts' comprehensive evaluation process, coordination ability was an important factor.

"We have paid more attention to assessing the astronauts' psychological coordination this time, as the two have to live together in a confined environment for a total of 33 days," Huang said.

"So when it comes to the coordination evaluation, we will choose those who are familiar with the candidates in making this assessment."

Huang also described the evaluation standards for selecting qualified astronauts. This includes qualities having to do with political thoughts, physical condition, psychological condition, professional knowledge and technical skills.

"We set up selection criteria especially for the Shenzhou-11 mission. We finally reached an agreement to choose one veteran and one relatively new one," she said.

"In this way, we can not only ensure the completion of the mission, but provide experienced astronauts for future aerospace missions."

When it comes to why two astronauts, but not three, were chosen, Huang says this made more sense for studying long spans of time in spaceflight.

"The flyability of the spacecraft is now 60 people per day, which means it can either carry two people for 30 days in the space, or three people for 20 days. 30 days is an extreme limit for an astronaut," she said.

"Many problems will appear in astronauts who stay in space for more than 30 days. So we choose to send two astronauts to space, as a testament to the effectiveness of our protection measures."

Huang also explains why a female astronaut was not selected for this Shenzhou mission. She says with this mission being the longest amount of time that Chinese astronauts will spend in space, it seemed wiser to go with two males instead of one male and one female.