The Tiangong space station is a space station placed in Low Earth orbit between 340 and 450 km above the surface. It will be roughly one-fifth the mass of the International Space Station and about the size of the Mir space station.
The China Aerospace Science and Technology Corporation (CASC) is the main contractor for the Chinese space program. It is state-owned and has a number of subordinate entities which design, develop and manufacture a range of spacecraft, launch vehicles, strategic and tactical missile systems, and ground equipment. It was officially established in July 1999 as part of a Chinese government reform drive, having previously been one part of the former China Aerospace Corporation. Various incarnations of the program date back to 1956.