Three Chinese astronauts have begun a six-month mission, to work on the country’s new space station.

It is China’s latest step towards making itself a leading space power for the decades ahead.

Last year, China put into orbit the first module of its Tiangong or “Heavenly Palace” space station. It plans to add more modules, such as Mengtian science lab, by the end of the year.

Next year, it will launch a space telescope, called Xuntian. This will fly close to the space station, and dock with it for servicing and refuelling.

Tiangong will have its own power, propulsion, life support systems and living quarters.

China is only the third country in history to have put both astronauts into space and to build a space station, after the Soviet Union (and now Russia) and the US.

It has big ambitions for Tiangong and hopes it will replace the International Space Station (ISS), which is due to be decommissioned in 2031.

Chinese astronauts are excluded from the ISS because US law bans its space agency, Nasa, from sharing its data with China.