Tiangong-3
# Tiangong-3

Tiangong-3 (Chinese: 天宫三号; pinyin: Tiāngōng sānhào; lit. 'Heavenly Palace 3') was a proposed Chinese space station, part of the Tiangong program. The China National Space Agency (CNSA) was originally expected to launch Tiangong-3 around 2015, following the launch of the Tiangong-2 test laboratory, originally planned for 2013. The goals for the Tiangong-2 and Tiangong-3 laboratories were merged, and the latter was therefore not ordered. The first module of the third station of the Tiangong program, Tiangong space station, was eventually launched in 2021.

## Development

In 2008, the China Manned Space Engineering Office (CMSEO) published a brief description of Tiangong-2 and Tiangong-3, indicating that several crewed spaceships would be launched in the late 2010s to dock with Tiangong-3. The first Tiangong module, Tiangong-1, was launched in September 2011 and docked with the uncrewed Shenzhou 8 spacecraft in November 2011, marking China's first orbital docking.

## Specifications

Tiangong-3 was expected to provide:

* Unaided 40-day habitability for three astronauts.
* Testing for regenerative life-support technology, and verification of methods of orbital replenishment of propellant and air.
* A multi-docking berthing mechanism, allowing up to two spacecraft to dock with it simultaneously.
