Two Pakistani pilots are spinning in centrifuge drills and learning to eat, sleep and repair equipment while weightless, as a decision nears on which one will become the first foreign astronaut aboard China's Tiangong space station.
The voyage into space would be a first for the South Asian nation.
It is part of broader cooperation with Beijing that includes a joint satellite-navigation system and a Pakistani-built rover due to fly on China's Chang'e 8 lunar mission around 2028.
Pilots Zeeshan Ali and Khurram Daud have spent months training at the China Astronaut Research and Training Centre in Beijing for a mission the two countries conceived in 2019, said Amer Gilani, who oversees human spaceflight cooperation at Pakistan's space agency, SUPARCO.
China has not said which of the two will fly or when, but Gilani said a final astronaut selection decision is expected in mid-to-late October.
Whoever is chosen will not return to Pakistan before launch, setting off into space directly from training in China and returning home after a recovery period following the return to Earth, Gilani told Reuters in an interview.
Training includes intensive Chinese-language instruction, learning spacecraft systems, and adapting to both the microgravity of orbit and the g-forces of liftoff, he added.
The two men beat out roughly 20 finalists culled from an initial pool of pilots and scientists, screened for medical fitness, psychological resilience and, according to SUPARCO's director of artificial intelligence Uzair Ansari, a tolerance for g-forces that few scientists possess.
"You cannot easily find scientists who are familiar with travelling and facing high-level g-forces," he said, explaining this is why the two men with backgrounds in high-speed flying were chosen.
The details shared by Gilani and Ansari are the first insight SUPARCO has provided to foreign media since the pilots were selected and deployed to China.
China's space agency did not respond to a request for comment about the selection process.
Modest payload
Once in space, the chosen pilot will carry the title of "payload specialist", which is astronaut-speak for someone whose job in orbit is running Pakistan's science experiments rather than flying the ship, Ansari said.
Of more than 300 proposals SUPARCO fielded from universities in Karachi, Lahore and Islamabad after a year-long campaign, Gilani said Chinese institutes picked four for this flight: biotechnology experiments that will help combat food insecurity and climate change.
Every experiment is built and pre-tested in SUPARCO's own labs before Chinese engineers sign off — a rare case, Ansari said, where Pakistani technology gets validated on an international platform.
The scientific payload is modest next to a station that has already hosted more than 180 experiments and produced over 500 research papers and 150 patents, Ansari added.
Tiangong's three modules — Tianhe, Wentian and Mengtian — weigh about 77 metric tons combined and house roughly 14 experiment racks spanning life sciences, materials, fluid physics, combustion and radiation exposure, Gilani said, including some mounted outside the station and exposed directly to space for materials and biotechnology payloads.
The Pakistani astronaut is due to return with two members of a Chinese crew that arrived at the space station in May because the third member is expected to stay for a year to enable the study of long-duration human physiology in space.
Since Yuri Gagarin's 1961 first flight, citizens of about 50 countries have flown in space, but only three nations — Russia, the US, and China — have launched their own crewed spacecraft.
Asked whether Islamabad had secured any promise to send an astronaut to the moon under the same partnership, Gilani said "there is no official commitment or discussion on this matter," adding that what comes next will depend on how "our maiden mission" turns out.
The Pakistani-built lunar rover that is due to fly on China's Chang'e 8 lunar mission around 2028 is a separate strand of that cooperation: it will use AI-based stereo imaging to detect obstacles, judge depth and plan its own path across the lunar surface, since Earth-based controllers cannot guide it in real time, Ansari said.
Still, Ansari was clear that the mission is a "once-in-a-lifetime opportunity" for Pakistani scientists.
