by Douglas Messier
In a few short weeks, the International Space Station (ISS) will no longer be the only station in Earth orbit.
China plans to launch the Tianhe core module core module of its first permanent space station aboard a Long March 5B rocket from the Wenchang Spacecraft Launch Site. Spaceflight Now‘s launch calendar has the flight taking place on April 29.
The three-section Tianhe module includes living quarters for the crew as well as the station’s power, propulsion, life support, guidance, navigation and orientation control. There is also a docking hub that includes ports for visiting vehicles and additional modules.
Tianhe is 16.6 meters long with a diameter of 4.2 meters and a launch weight of 22,000 kg. It is longer than the core module of the Soviet Union’s Mir space station, which had a length of 13.13 meters, a diameter of 4.15 meters and a weight of 22,400 kg.
Launch of the core module will begin a busy two-year period that will see additional modules attached to Tianhe and the launch of multiple Shenzhou crew vehicles and Tianzhou cargo ships.
Spaceflight Now‘s launch calendar indicates that the Tianzhou-2 cargo ship aboard a Long March 7 rocket in May. The booster for the flight recently arrived at Wenchang.
The first crew to occupy the new station will likely be launched in June aboard the Shenzhou-12 spacecraft. A Long March 2F will launch the astronauts to the station.
Later crew flights will be aboard China’s next-generation crewed spacecraft, which will be capable of carrying six or seven astronauts. The new vehicle is being designed for trips to the moon.
In 2022, China will launch the Wentian and Mengtian experiment modules aboard Long March 5 rockets from Wenchang. The modules are each 14.4 meters long with diameters of 4.2 meters and masses of 20,000 kg.
When fully assembled, the space station will be similar in size to the Soviet Mir station. It will have a mass of about one quarter that of the ISS.
Tianhe will be China’s third space station and the first one to be permanently crewed. The nation previously launched smaller single module Tiangong-1 and Tiangong-2 that were occupied for relatively brief periods of time.
Launched in September 2011, Tiangong-1 was occupied for a total of nearly 21 days by the crews of Shenzhou-9 and Shenzou-10. Tiangong-2 was launched in 2016 and occupied for more than 26 days by the crew of Shenzhou-11.
In April 2017, the Tianzhou-1 cargo ship docked with the Tiangong-2 and refueled the uncrewed space station. The freighter later twice undocked and redocked with the station.