What nations may send astronauts to Tiangong?

China is currently operating its Tiangong Space Station in low Earth orbit. So far the station has only been home to Chinese astronauts (taikonauts).

Despite only flying taikonauts to Tiangong, China is open to flying foreign astronauts to the station and has been since the development stage of the modular space station. Offers as low as free have recently been made to potential foreign partners, this offer massively undercuts the current for-profit services from Axiom space and future commercial space stations.

So, where could Tiangong's international astronauts come from?

Europe

The European Space Agency (ESA) already has a strong astronaut corps, alongside this the agency has also conducted joint training with the China Manned Space Agency.

The first joint training between the two agencies had Ye Guangfu head to Italy to join ESA's Cooperative Adventure for Valuing and Exercising human behavior and performance Skills (CAVES) underground training course back in July 2016. This training course had Ye working with astronauts from Japan, Russia, Spain, and the United States to complete climbing, exploration, and surveying.

A little over a year later in August 2017 two ESA astronauts, Samantha Cristoforetti and Matthias Maurer, head to China to train alongside over a dozen taikonauts for sea survival training. Cristoforetti and Maurer worked alongside two taikonauts each to practice sea-based rescue procedures, which would occur after a relatively late abort during launch in the real world. Speaking on the training, Cristoforetti said:

"Importantly, we were welcomed as colleagues and friends by the ‘taikonauts’ and the instructors. Language and cultural differences are obviously a challenge, but also adds value, as we are all focused on the common goal of space exploration."

Both joint training activities came from a 2015 agreement to boost collaboration between ESA and the China Manned Space Agency with the eventual goal of flying European astronauts to the Tiangong Space Station. By 2023 however, ESA's Director General, Josef Aschbacher, disclosed that there was neither the budget nor political will to send astronauts to Tiangong. At the time of writing it is unclear if the potential offer of a free mission to Tiangong has rekindled ESA's interest.

ESA has also provided two instruments for the Chang'e lunar mission, which returned the first lunar samples from the far side. The instruments provided were Negative Ions on Lunar Surface (NILS) and INstrument for landing-Roving laser Retroreflector Investigations (INRRI). France, ESA's second largest funding contributor, is also currently conducting a joint scientific mission with China called SVOM, which is dedicated to studying gamma-ray bursts.

Brazil

Brazil is one of China's oldest space partners, with both nations signing the China-Brazil Earth Resources Satellite program (CBERS) in July 1988. Since the program's establishment five satellites have been placed into operational orbits for use in surveying natural resources, agriculture, forestry, geology, water resources, as well as for urban planning and environmental protection. Two more CBERS satellites are currently under development too.

In April 2023 China and Brazil signed a supplementary protocol on cooperation for a 2023-2032 space cooperation plan between both nation's space programs, this agreement is expected to materialize in collaboration around the Moon and in deep space. Brazil was also the first country to sign an agreement allowing for one of China's internet mega-constellations, Qianfan (千帆), to provide services.

So far Brazil has had one astronaut, Marcos Cesar Pontes. Pontes flew to space in 2006 aboard the Soyuz TMA-8 mission and proceeded to spend nine days and twenty-one hours in space before returning to Earth with the Soyuz TMA-7 crew.

Pakistan

Pakistan and China have been cooperating in space since the 1980s, making them another one of China's oldest space partners, and are both members of the Asia-Pacific Space Cooperation Organization. This cooperation was initially focused on technical assistance, personnel training, and infrastructure development.

In the opening months of the 1990s, Pakistan's first satellite, Badr-1 (بدر-۱), was sent into orbit by a Long March 2E. Since then the two countries have worked together on PakSAT-1R, launched by a Long March 3B/E, PaksSAT-MM1R, also launched by a Long March 3B/E, as well as PakTES-1A and PRSS-1, launched together by a Long March 2C. Pakistan also contributed to the Chang'e 6 mission with the ICUBE-Q satellite, designed to verify nanosatellite technologies for deep space exploration.

To date Pakistan has one astronaut, Namira Salim (نمیرا سلیم). Salim spent approximately fifteen minutes in space as part of the suborbital Galactic 04 mission, before which she visited the North Pole in 2007, the South Pole in 2008, and participated in a Mount Everest Skydive in 2008.

What does China get out of this?

With the potential of offering free missions to Tiangong, some eyebrows have been raised about what China is possibly getting out of flying international astronauts to its space station.

A possibility is that China may be hoping to make Tiangong an unofficial successor to the International Space Station project, which has conducted science collaboratively in orbit since 1999. International science experiments have already been conducted aboard Tiangong, with plans to send experiments from Poland, India, Switzerland, Germany, Kenya, Italy, Japan, Mexico, Spain, Russia, Saudi Arabia, and Peru to the station via the United Nations Office for Outer Space Affairs in the coming years. A nation sending an astronaut up to Tiangong would be a likely next step for a country already conducting several experiments onboard.

In return for flying international experiments, and possibly people soon, to Tianong, China gets part of the results from the experiments as well as prestige in the international community, both political and scientific. This prestige may make Tiangong a premier destination for science in Earth orbit until its decommissioning in the 2040s.

What is the Tiangong Space Station?

The Tiangong Space Station, also called the Chinese Space Station, is a permanently crewed space station in low Earth orbit operated by the China Manned Space Agency and China National Space Administration.

The space station consists of the Tianhe core module, the Wentian laboratory module, and the Mengtian laboratory module. With these modules, the station has three docking ports for visiting spacecraft to dock located on the Tianhe module, one port is located at the aft end of the module, and two and the forward end with one facing Earth. The combined habitable volume of the space station is believed to be 122 cubic meters, with a total pressurized volume of 340 cubic meters.

Each of the three modules were launched by the Long March 5B, with Tianhe launching on the 29th of April 2021, followed by Wentian on the 24th of July 2022, with the latest edition being Mengtian on the 31st of October 2022. China currently plans to launch the Xuntian space telescope which will co-orbit with the space station for periodic docking for servicing and maintenance by crews onboard.

For more about the space station and its future click here.