Tiangong (Chinese: 天宫; pinyin: Tiāngōng; lit.: 'Heaven's Palace') is a space station program of the People's Republic of China, with the goal of creating a modular space station, comparable to Mir. This program is independent and unconnected to any other international space-active countries. The program began in 1992 as Project 921-2. As of January 2013[update], China moved forward on a large multiphase construction program that will lead to a large space station around 2020.
China launched its first space laboratory, Tiangong-1, on September 29, 2011. Following Tiangong-1, a more advanced space laboratory complete with cargo ship, dubbed Tiangong-2, was launched on September 15, 2016. The project will culminate with a large orbital station, which will consist of a 20-ton core module, 2 smaller research modules, and cargo transport craft. It will support three astronauts for long-term habitation and was scheduled to be completed by 2020 just as the International Space Station was at that time scheduled to be retired, but this has since slipped to 2024.
After the United States threatened to use nuclear weapons during the Korean War, Chairman Mao Zedong decided that only a nuclear deterrent of its own would guarantee the security of the newly founded PRC. Thus, Mao announced his decision to develop China's own strategic weapons, including associated missiles. After the launch of mankind's first artificial satellite, Sputnik 1 by the Soviet Union on 4 October 1957, Chairman Mao decided to put China on an equal footing with the superpowers ("我们也要搞人造卫星"), using Project 581 with the idea of putting a satellite in orbit by 1959 to celebrate the 10th anniversary of the PRC's founding. However, it would not be until 24 April 1970 that this goal would become a reality.
Mao and Zhou Enlai began the PRCs crewed space program on 14 July 1967. China's first crewed spacecraft design was named Shuguang-1 (曙光一号) in January 1968. Project 714 was officially adopted in April 1971 with the goal of sending two astronauts into space by 1973 aboard the Shuguang spacecraft. The first screening process for astronauts had already ended on 15 March 1971, with 19 astronauts chosen. The program was soon cancelled due to political turmoil.
The next crewed space program was even more ambitious and was proposed in March 1986 as Project 863. This consisted of a crewed spacecraft (Project 863-204) used to ferry astronaut crews to a space station (Project 863-205). Several spaceplane designs were rejected two years later and a simpler space capsule was chosen instead. Although the project did not achieve its goals, it would ultimately become the 1992 Project 921, encompassing the Shenzhou program, the Tiangong program, and the Chinese space station.
On the 50th anniversary of the PRC's founding, China launched the Shenzhou 1 spacecraft on 20 November 1999 and recovered it after a flight of 21 hours. The country became the third country with a successful crewed space program by sending Yang Liwei into space aboard Shenzhou 5 on October 15, 2003 for more than 21 hours. It was a major success for Chinese space programmes.
In 1999, Project 921-2 was finally given official authorization. Two versions of the station were studied: an 8-metric ton "space laboratory" and 20-metric ton "space station".
In 2000, the first model of the planned space station was unveiled at Expo 2000 in Hanover, Germany. This was made up of modules derived from the orbital module of the Shenzhou spacecraft. Overall length of the station would be around 20 m, with a total mass of under 40 metric tons, with possibility of expansion through addition of further modules.
In 2001, Chinese engineers described a three-step process toward the realization of Project 921. The original target date for the fulfillment of the project was 2010.
Originally, China planned to simply dock Shenzhou 8 and Shenzhou 9 together to form a simple space laboratory. However, it was decided to abandon that plan and launch a small space laboratory instead. In 2007, plans for an 8-metric ton "space laboratory" being launched in 2010 under the designation of Tiangong-1 were made public. This would be an eight-ton space laboratory module with two docking ports. Subsequent flights (Shenzhou 9 and Shenzhou 10) will dock with the laboratory.
On September 29, 2008, Zhang Jianqi (张建启), Vice Director of China crewed space engineering, declared in an interview of China Central Television it is Tiangong-1 (i.e. not Shenzhou 8) that will be the 8-ton "target vehicle", and Shenzhou 8, Shenzhou 9, and Shenzhou 10 will all be spaceships to dock with Tiangong-1 in turn.
On October 1, 2008, Shanghai Space Administration, which participated in the development of Shenzhou 8, stated that they succeeded in the simulated experiments for the docking of Tiangong-1 and Shenzhou 8.
On June 16, 2012, Shenzhou 9 was launched from Jiuquan Satellite Launch Center in Inner Mongolia, China, carrying a crew of three. The Shenzhou craft successfully docked with the Tiangong-1 laboratory on June 18, 2012, at 06:07 UTC, marking China's first crewed spacecraft docking.
The Chinese docking target consists of a propulsion (resource) module and a pressurized module for experiments, with a docking mechanism at either end. The docking port of the experiment section supports automated docking. Its length is 10.5 metres (34 ft), diameter is 3.4 metres (11 ft), with a mass of 8,000 kilograms (18,000 lb). Launched on September 29, 2011, it was intended for short stays of a crew of three. The second docking port, on the propulsion module, was kept screened from press photography inside and outside the module. It re-entered and burned up in the atmosphere on April 2, 2018, at 00:16 UTC.
A second and a third test station were originally planned to precede the eventual modular station. These would be 14.4 metres (47 ft) long, with a diameter of 4.2 metres (14 ft), and weigh up to 20,000 kilograms (44,000 lb). The second one would provide life support for a crew of 2 for 20 days, and the third one a crew of 3 for 40 days. However, all the objectives of these two stations were later merged into one project, and the size scaled down to less than 10,000 kilograms (22,000 lb).
A third space station proposed but later cancelled in favor of advancing to the new large modular station.
Drawing of Shenzhou and Cargo ship docked to the large orbital station
|Length||~ 20.00 m|
|Diameter||~ 3.00 m|
China plans to build the world's third multi-module space station, to follow Mir and the ISS. This was dependent upon the date of OPSEK's separation from the ISS but after a statement in September 2017, the head of Roscosmos Igor Komarov said that the technical feasibility of separating the station to form OPSEK had been studied and there were now "no plans to separate the Russian segment from the ISS”. The previous separate components will be integrated into a space station, arranged as:
The larger station will be assembled in 2020–2022 and have a design lifetime of ten years. The complex will weigh approximately 60,000 kilograms (130,000 lb) and will support three astronauts for long-term habitation. The public is being asked to submit suggestions for names and symbols to adorn the space station and cargo ship. "Considering past achievements and the bright future, we feel that the crewed space program should have a more vivid symbol and that the future space station should carry a resounding and encouraging name", Wang Wenbao, director of the office, said at the news conference. "We now feel that the public should be involved in the names and symbols as this major project will enhance national prestige, and strengthen the national sense of cohesion and pride", Wang said.
After the success of China's crewed space launch, a Chinese official expressed interest in joining the International Space Station program. In 2010, ESA Director-General Jean-Jacques Dordain stated that his agency was ready to propose to the other 4 partners that China, India, and South Korea be invited to join the ISS partnership. China has indicated a willingness to cooperate further with other countries on crewed exploration.
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".
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.
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