|Mass||22,000 kilograms (49,000 lb)|
|Length||18.1 meters (59 ft)|
|Diameter||4.2 meters (14 ft)|
Tiangong-3 (Chinese: 天宫三号; pinyin: Tiāngōng sānhào; lit. 'Heavenly Palace 3') was a proposed Chinese space station, part of the Tiangong space station program. The China National Space Agency 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 eventually merged, and the latter was therefore not ordered.
In 2008, the China Manned Space Engineering Office 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.
Tiangong-3's 22-metric-ton core module was expected to be around 18.1 metres (59 ft) long and have a maximum diameter of 4.2 metres (14 ft). It was expected to provide:
China is ready to carry out a multiphase construction program that leads to the large space station around 2020. As a prelude to building that facility, China is set to loft the Tiangong-1 module this year as a platform to help master key rendezvous and docking technologies.
China often chooses poetic names for its space projects, such as Chang'e – after the moon goddess – for its lunar probes; its rocket series, however, is named Long March, in tribute to communist history. The space station project is currently referred to as Tiangong, or "heavenly palace".