On 17 June 2021,China's spacecraft Shenzhou 12 took three Chinese astronauts into the Earth's orbit and docked with the assembly of Tianhe and Tianzhou,the core module and cargo ship of the Chinese Space Station (CSS),which had been launched and assembled in orbit earlier this year.The three astronauts became the first visitors of the CSS and would stay in orbit for about three months.In 2022,two laboratory cabin modules,Wentian and Mengtian,will be launched and assembled into Tianhe,completing the basic structure of the CSS.The CSS is designed to be used for at least 10years,and will provide an outer space experimental platform for researchers from multiple disciplines.