China launched Tianhe, the core cabin module of its Tiangong space station, on April 29, 2021, thus kicking off a series of key missions to complete construction of the station. 

Tianhe acts as the management and control hub of Tiangong (“Heavenly Palace” in Chinese), with a node that can dock with up to three spacecraft at a time for short stays, or two for long stays. 

Tianhe has a total length of 16.6 meters, a maximum diameter of 4.2 meters and a takeoff mass of 22.5 tonnes, making it the largest spacecraft ever developed by China. 

The space station has a T-shape with the core module at the center and a lab capsule on each side. Each module is over 20 tonnes. When the station docks with both manned and cargo spacecraft, its weight can reach nearly 100 tonnes. 

The station operates in low-Earth orbit at an altitude of 340–450 km. It has a design life of 10 years, but experts believe it could last more than 15 years with appropriate maintenance and repairs. 

China launched Tianzhou-2 on May 29, 2021 and the cargo craft docked with Tianhe on May 30. 

Less than three weeks later, on June 17, the manned spaceship Shenzhou 12 was successfully launched and performed a fast autonomous rendezvous and docking with the front docking port of Tianhe, forming a three-module complex with Tianzhou-2. This was the first time Tianhe had docked with a manned spacecraft since it went into orbit. 

The three astronauts aboard Shenzhou 12—NIE Haisheng, LIU Boming and TANG Hongbo—then entered the Tianhe module. They stayed in the core module for three months and carried out a series of space science and technology experiments. 

Key technologies for the construction and operation of the space station were verified in orbit, including those related to long-term astronaut residence, regeneration and health care, space supply, extravehicular activities and operations, and in-orbit maintenance. 

On Oct. 16, about a month after the return of the Shenzhou 12 astronauts, the crewed spaceship Shenzhou 13 was launched and subsequently docked with the radial port of Tianhe. The mission’s three Chinese astronauts—ZHAI Zhigang, WANG Yaping and YE Guangfu—then entered the orbital capsule from the spaceship’s return capsule. 

During the astronauts’ six-month stay in orbit, they operated its mechanical arm and carried out extravehicular activities and work related to translocation of the station’s modules. They also conducted space science experiments and technology tests, including verifying a series of key technologies related to long-term in-orbit residence of astronauts and regeneration and life support systems, etc.