For Matthias Maurer, an astronaut at the European Space Agency, the experience of training with Chinese spaceflight experts was overall pleasant.

In an interview with BBC Future, Maurer said his sea survival training in Yantai was far from his expectations. The Chinese bonded "like brothers and sisters" even when the training sessions are over like going on vacations together.

"It felt like being part of a family — it was completely different to being in Houston, where I rent an apartment and see my colleagues only during a two or three-hour training session," Maurer said, adding that he stayed in the same building together with his Chinese peers.

Maurer said his stay at ESA's training facility in Houston, Texas is completely different. They only get to see their colleagues during their two- or three-hour training sessions. Compared to the Russian sea survival training, China's had inflatable rubber boats which make jumping into the water easier.

Europe-China Collaboration

In August 2017, Maurer and fellow ESA astronaut Samantha Cristoforetti joined 16 Chinese astronauts in nine-day sea survival training. ESA said their primary goal is to establish a long-term relationship for future space missions.

"The training was superbly planned and conducted. It was a great opportunity to refresh my skills and a first time [practicing] capsule egress in the ocean with decent waves. Most importantly, we were welcomed as colleagues and friends by the 'taikonauts' and the instructors," Cristoforetti said.

The Shenzhou spacecraft, which carried the first Chinese astronaut into the Earth's orbit in 2003, is modeled largely on Russia's Soyuz. Maurer said the difference is that Shenzhou took the good hardware from Soyuz and followed through the improvements.

Language became the single most challenging aspect of their training, but it was overcome since the crew spoke both Chinese and English. Currently, ESA is in cooperation with 23 nations, including the United States and Russia.

Building The Chinese Space Station

In its efforts to join the new space race, China is building its own space habitat, which is expected to become functional by 2023. Meanwhile, China's Queqiao spacecraft is preparing for a lunar rover mission slated by the end of this year.

China is also inviting other United Nations member states to submit applications for future space experiments. Approved proposals shall allow researchers to use the facilities inside the China Space Station.

Ambassador to the UN Shi Zhongjun cited the UN's 50-year-old Outer Space Treaty, which stated that space exploration should be harmonious and beneficial to all countries.