Inside Tiangong: Crew Life on China’s Three-Module Space Station

China's Tiangong space station reached full operation when the third module, Mengtian, docked, and Shenzhou 15 then arrived for the first in-orbit crew handover, putting six taikonauts aboard at once. The station orbits around 400 kilometers above Earth.

Three modules in a T shape

Tianhe is the core command module, first launched in April 2021. Wentian, added in July 2022, combines crew quarters, a research lab and an airlock. Mengtian is a twin to Wentian and works purely as a research and experiment space.

More room than the ISS

The module diameter is about 4.2 meters (14 feet), nearly the same as ISS modules, but the interior feels more spacious. The ISS Destiny lab is 8.4 meters (28 feet) long, while Wentian and Mengtian are each 18 meters (59 feet). The video also notes that many Tiangong systems connect wirelessly rather than through a maze of cables, and much equipment is hidden behind plain white panels.

Spacewalks and robotic arms

Three Chinese-made EVA suits are kept in the Wentian airlock. The Tianhe module has a 10-meter arm and Wentian has a five-meter arm, and the two can combine into one 15-meter arm. The video compares this with the 17-meter Canadarm2 on the ISS. In a spacewalk in mid-November, the crew installed inter-module connection devices, essentially handrails for moving around the exterior of all three modules.

Daily life

Footholds are mounted on the floor, and the crew is usually strapped in rather than free-floating. They sleep upright in a bag in one of six alcoves with a curtain. The crew grows fresh lettuce and vegetables and receives fresh fruit such as apples.

The station has a space microwave oven, developed in China over 10 years and built to survive launch on the Long March 5B. It heats a meal for three in seven minutes. The ISS has never had one because the power draw would be too high, and uses a food warmer that takes 20 to 30 minutes.

For exercise, Tiangong has a treadmill and cycling station, and Mengtian came with a rowing machine for resistance training. ISS crews exercise at least two hours a day.

Research and what comes next

With Mengtian, Tiangong has 23 experiment racks and 50 platforms for exposed experiments outside. Research areas include ecology and biology, fluid physics, combustion, materials science and varying gravity. Mengtian has an airlock that automatically depressurizes experiments and sends them outside, where a robotic arm or a spacewalking crew member attaches them.

The next addition is planned to be the Xuntian telescope module, still under development, with a 2-meter primary mirror, a field of view around 300 times wider than Hubble's and a 2.5-gigapixel camera. China is also considering an extension module for the forward section, and a backup Tianhe core module exists that could create a cross-shaped station. Nine international research projects are due to arrive in 2023, in collaboration with the United Nations Office for Outer Space Affairs and the European Space Agency.