In fewer than 18 months, China plans to launch a third module to complete the Tiangong space station.

China's human spaceflight agency reported that the Mengtian experiment module landed at Wenchang spaceport in south China on Tuesday (Aug. 9) after being transported in containers from the northern port city of Tianjin.

Next, Mengtian will be put together and tested in Wenchang in anticipation of its scheduled launch on a Long March 5B rocket in October. The 58.7-foot-long (17.9-meter) module will join the Tianhe core module and Wentian experiment module to complete the T-shaped Tiangong space station by docking in orbit with a connecting hub at the space station then being transferred to a lateral port.

Mengtian, which means "Dreaming of Heavens," or officially the Mengtian Laboratory Cabin Module is a major module of the Tiangong Space Station. It will be the second Laboratory Cabin Module launched, and the second module to extend the existing Tianhe core module of the station.

In April 2021, China launched Tianhe ("Harmony of the Heavens"), which is the first module to launch the Tiangong space station. And last month it added the experiment module Wentian ("Quest for the Heavens") to the orbital complex. The massive first stage of their Long March 5B rockets reentered the atmosphere uncontrollably during both flights, which will probably happen once more following the Mengtian launch.

Mengtian will include several science cabinets where various experiments can be carried out. Additionally, it features a payload airlock that enables the small robotic arm of the station to take science payloads and place them on an experiment platform outside the module.

The country intends to keep the Tiangong space station operational for at least ten years and may allow commercial missions and tourist visits. The finished Tiangong will be nearly 20% larger than the International Space Station, which on Earth would weigh around 460 tons, with visiting cargo and the Shenzhou crewed spacecraft docked.

On June 5 this year, Shenzhou 14 astronauts Chen Dong, Liu Yang, and Cai Xuzhe launched from Earth and docked with Tianhe, the main module of the Tiangong space station that is still being built. So far, the crew has been exercising on treadmills and stationary bikes to reduce the impact of microgravity on their bodies. The crew will be in orbit for six months, supervising the arrival of the new modules that will complete the T-shaped orbital outpost.