Work on China’s Tiangong Space Station began in earnest on Thursday, with the first of several modules sent into near-Earth orbit aboard a Long March 5 heavy rocket. The module Tianhe – which means “heavenly harmony” – was blasted off from the southern island province of Hainan at 11.23am local time. The 22 tonne component will serve as the core of the Tiangong, or “Heavenly Palace”, where astronauts will spend most of their time. “The successful launch of the Tianhe core module indicates that the construction of our country’s space station has entered the stage of full implementation and laid a solid foundation for subsequent missions,” President Xi Jinping said. “The construction of a space station and the establishment of a national space laboratory... is an important leading project for building a powerful country in science and technology and aerospace.” Two separate launches in the coming weeks will send cargo and three astronauts to the core module, which is about the size of a five-storey building and can accommodate up to six astronauts. Water on board will be fully recycled. The space station is expected to be completed next year and have a mass of about 100 tonnes. That would make it only about a quarter of the size of the International Space Station (ISS), built by a coalition of 16 countries. But at 15 years old, the ISS is ageing. Astronauts have had to spend more time finding and patching holes in the space station and Russia announced on Monday that it would quit the project in 2025. China approves bid to build fifth rocket launch site as Zhejiang province fires up for space boom The Tiangong is expected to be the only space station operating in near-Earth orbit by the end of the decade. China embarked on the project after the US rejected China’s request to join the ISS. “They said we were not up to the standard. They said we were thieves,” a senior Chinese space scientist involved in the negotiations in the 1990s said. “We could not swallow the humiliation, so we decided to build our own station.” Scientists from 16 other countries have joined the Tiangong programme, and will contribute engineering expertise or team up with Chinese scientists to conduct a wide range of experiments, according to China’s space authorities. China names its Mars rover Zhu Rong after mythical god of war A research team from the US had applied, but was rejected because the quality of their proposal was “not up to the standard”, according to Zhou Jianping, the Tiangong’s chief designer. A study commissioned by the Chinese government on international cooperation for the Tiangong found China and the US had “many opportunities to collaborate in space”, particularly in astronomy, climate change, space weather forecasting, and clearing space debris. But according to the study’s lead author Jiang Shengli, a space law researcher at East China University of Political Science and Law in Shanghai, there could be legal obstacles to these kinds of joint efforts because the US Congress had outlawed any state-funded cooperation between China and the US in space. “It remains highly uncertain whether China and the US, the two most important powers in space, can work together on the space station project,” he said in the study published in a domestic journal last year. “[This means] China’s model for international cooperation is not guaranteed to work as planned.” China had learned several lessons from the ISS, including the need to avoid confusion over ownership and management associated with building different parts of the ISS in different countries, Jiang said. China would maintain full control of the Tiangong’s construction, management and future development while allowing other countries, especially those from the developing world, to contribute hardware, technology or talent to the semi-open platform, he said. Chinese space authorities said the Tiangong station would give a boost to the Chinese economy , which depended increasingly on science and technology. Cutting-edge space technology developed for the Tiangong, including new materials, robotics and artificial intelligence could be used in wider commercial applications, they added.