Shenzhou (spacecraft)
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This article may require cleanup to meet Wikipedia's quality standards. Please improve this article if you can. (September 2009) |
A model of the Shenzhou spacecraft |
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| Organization | CNSA |
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| Mission type | Orbiter |
| Satellite of | Earth |
| Launch vehicle | Long March 2F launch vehicle |
| Launch site | Jiuquan Satellite Launch Center |
Shenzhou (Chinese: 神舟; pinyin: Shén Zhōu) is a spacecraft developed and operated by the People's Republic of China to support its manned spaceflight program. The name is variously translated as "Divine Craft," "Divine Vessel of the Gods," "Magic Boat" or similar, and is identically pronounced, though differently written, with a literary name for China (神州; literally "Divine Land").[citation needed] Its design resembles the Russian Soyuz spacecraft, but it is larger in size and all-new in construction. Moreover, unlike the Soyuz, the orbital module of the Shenzhou is equipped with its own propulsion, solar power, and control systems, allowing autonomous flight. The first manned launch was on October 15, 2003. In March 2005, an asteroid was named 8256 Shenzhou in honor of the spacecraft.
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[edit] History
China's first efforts at human spaceflight started in 1968 with a projected launch date of 1973.[1] Although China did launch an unmanned satellite in 1970 and has maintained an active unmanned program since, this attempt was canceled due to lack of funds and political interest.
The current Chinese human spaceflight program was authorized on April 1, 1992 as Project 921/1, with work beginning on January 1, 1993. The initial plan had three phases:
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- Phase 1 would involve launch of two unmanned versions of the manned spacecraft, followed by the first Chinese manned spaceflight, by 2002.
- Phase 2 would run through 2007, and involve a series of flights to prove the technology, conduct rendezvous and docking operations in orbit, and operate an 8-tonne spacelab using the basic spacecraft technology.
- Phase 3 would involve orbiting of a 20-ton space station in the 2010-2015 period, with crews being shuttled to it using the eight-ton manned spacecraft.
The chief designers of the Shenzhou include Qi Faren and Wang Yongzhi.
The first four unmanned test flights happened in 1999, 2001, and 2002. These were followed by manned launches on October 15, 2003, October 12, 2005, and September 25, 2008. It would be launched on the Long March 2F from the Jiuquan Satellite Launch Center. The command center for missions is the Beijing Aerospace Command and Control Center.
The first unmanned flight of the spacecraft was launched on November 19, 1999 after which Project 921/1 was renamed Shenzhou, a name reportedly chosen by Jiang Zemin. A series of three additional unmanned flights ensued. The Shenzhou reentry modules used to date are 13 percent larger than Soyuz reentry modules, and it is expected that later crafts will be designed to carry a crew of four instead of Soyuz's three, although physical limitations on astronaut size, as experienced with earlier incarnations of Soyuz, will likely apply.
While the Shenzhou orbital module could be used for military reconnaissance there appears to be no military reason for incorporating such as system in a manned mission, as China could use purely unmanned satellites for these purposes. The experience during the 1960s of both the United States with the Manned Orbiting Laboratory and the Soviet Union with the Almaz space station suggests that the military usefulness of human spaceflight is quite limited and that practically all military uses of space are much more effectively performed by unmanned satellites. Yet, the nature of space exploration, with different nations trying successively to achieve the same goals (e.g., the original "space race," current efforts to duplicate GPS and GLONASS with Galileo), implies that China may well be walking down this route as others have before them.
The fifth launch, Shenzhou 5, was the first to carry a human (Yang Liwei) and occurred at 9:00 CST (UTC +8) on October 15, 2003.
[edit] Missions launched
- Shenzhou 1 - November 19, 1999 - unmanned test flight
- Shenzhou 2 - January 9, 2001 - carried animals
- Shenzhou 3 - March 25, 2002 - carried a test dummy
- Shenzhou 4 - December 29, 2002 - carried a test dummy and several science experiments
- Shenzhou 5 - October 15, 2003 - 14 Earth orbits carrying Yang Liwei
- Shenzhou 6 - October 12, 2005 - five day mission with Fei Junlong and Nie Haisheng
- Shenzhou 7 - September 25, 2008 - three man crew with Zhai Zhigang, Liu Boming, and Jing Haipeng; spacewalk performed by two crew members
[edit] Planned missions
- Shenzhou 8 - 2010 (?) - unmanned mission, will rendezvous and dock with Tiangong 1.
- Shenzhou 9 - 2010 (?) - unmanned mission, will dock with Tiangong 1 after Shenzhou 8.
- Shenzhou 10 - 2010 (?) - three person crew, will dock with Tiangong 1 after Shenzhou 8 and Shenzhou 9 to form a space station or space laboratory.
- Shenzhou 11 - 2012 (?) - manned mission carrying the second space laboratory crew to Tiangong 2.[2]
This is similar to the process used by the Soviet Union in their early Soyuz program which was intended to test procedures for future lunar flights. The Shenzhou spacecraft closely resembles Soyuz, although it is substantially larger,[3] and unlike the Soyuz, it features a powered orbital module capable of autonomous flight.
The similarity in outward appearance between Shenzhou and Soyuz arises partially from basic constraints on space flight.[4] Like Soyuz, Shenzhou consists of three modules: a forward orbital module (轨道舱), a reentry module (返回舱) in the middle, and an aft service module (推进舱). This division is based on the principle of minimizing the amount of material to be returned to Earth. Anything placed in the orbital or service modules does not require heat shielding, and this greatly increases the space available in the spacecraft without increasing weight as much as it would if those modules were also able to withstand reentry. Thus both Soyuz and Shenzhou have more living area with less weight than the Apollo CSM.
[edit] Orbital module
The orbital module (轨道舱) contains space for experiments, crew-serviced or operated equipment, and in-orbit habitation. Without docking systems, Shenzhou 1-6 carried different kinds of payload on the top of their orbital modules for scientific experiments.
Unlike the Soyuz, the Shenzhou orbital module is also equipped with its own propulsion, and control systems, allowing autonomous flight. It is possible for Shenzhou to leave an orbital module in orbit for redocking by a later spacecraft, something which the Soyuz cannot do since the hatch enabling it to function as an airlock is part of its reentry module. In the future it is possible that the orbital module(s) could also be left behind on the planned Chinese project 921/2 space station as additional station modules. The fact that China has yet to deploy a space station (e.g., something equivalent to Salyut such as a module that has been re-docked with after deployment) implies an equivalent stage of progress to Russia pre-1970.[4]
In the unmanned test flights launched to date, the orbital module of each Shenzhou was left functioning on orbit for several days after the reentry modules return, and the Shenzhou 5 orbital module continued to operate for six months after launch.
Orbital module data
- Design Life: 200 days.
- Length: 2.80 m (9.10 ft).
- Basic Diameter: 2.25 m (7.38 ft).
- Maximum Diameter: 2.25 m (7.38 ft).
- Span: 10.40 m (34.10 ft).
- Habitable Volume: 8.00 m³.
- Mass: 1,500 kg (3,300 lb).
- RCS Coarse No x Thrust: 16 x 5 N.
- RCS Propellants: Hydrazine.
- Electrical System: Solar panels, 12.24 m².
- Electric System: 0.50 average kW.
- Electric System: 1.20 kWh.
[edit] Reentry module
The reentry module (返回舱) is located in the middle section of the spacecraft and contains seating for the crew. It is the only portion of Shenzhou which returns to Earth's surface. Its shape is a compromise between maximizing living space while allowing for some aerodynamic control upon reentry.
Reentry module data
- Crew Size: 3.
- Design Life: 20 days.
- Length: 2.50 m (8.20 ft).
- Basic Diameter: 2.52 m (8.26 ft).
- Maximum Diameter: 2.52 m (8.26 ft).
- Habitable Volume: 6.00 m³.
- Mass: 3,240 kg (7,140 lb).
- Heat Shield Mass: 450 kg (990 lb)
- RCS Coarse No x Thrust: 8 x 150 N.
- RCS Propellants: Hydrazine
[edit] Service module
The aft service module (推进舱) contains life support and other equipment required for the functioning of Shenzhou. Two pairs of solar panels, one pair on the service module, the other pair on the orbital module, have a total area of over 40 m² (430 ft²), indicating average electrical power over 1.5 kW (Soyuz have 1.0 kW).
Service module data
- Design Life: 20 days.
- Length: 2.94 m (9.65 ft).
- Basic Diameter: 2.50 m (8.20 ft).
- Maximum Diameter: 2.80 m (9.10 ft).
- Span: 17.00 m (55.00 ft).
- Mass: 3,000 kg (6,600 lb).
- RCS Coarse No x Thrust: 8 x 150 N.
- RCS Fine No x Thrust: 16 x 5 N.
- RCS Propellants: N2O4/MMH, unified system with main engine.
- Main Engine: 4 x 2500 N.
- Main Engine Thrust: 10.000 kN (2,248 lbf).
- Main Engine Propellants: N2O4/MMH.
- Main Engine Propellants: 1,000 kg (2,200 lb).
- Main Engine Isp: 290 sec. L/D Hypersonic: 0.30.
- Electrical System: Solar panels, 24.48 + 12.24 m², 36.72 m² total.
- Electric System: 1.00 average kW.
- Electric System: 2.40 kWh.
[edit] Shenzhou "space laboratory module"
It has been stated by some sources [2][5][6][7][8] that Shenzhou 8 would be an "8-ton small space laboratory" or "8-ton space station," and Shenzhou 9 and Shenzhou 10 will dock with it; but at 29 Sept. 2008, Zhang Jianqi (张建启), Vice Director of China manned space engineering, declared in an interview of China Central Television [9] 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.
According to China Daily (2008-09-29) Zhang Bainan, chief designer of the spacecraft system of China's manned space program, has declared that Shenzhou 8 will be a final, improved version of earlier Shenzhou spacecraft.
[edit] See also
- Long March rocket
- Project 921-2
- Tiangong
- Space program of China
- China National Space Administration
- Harbin Institute of Technology
- Beijing University of Aeronautics and Astronautics
[edit] References
| Wikimedia Commons has media related to: Shenzhou |
- ^ Mark Wade (2009). "Shuguang 1". Encyclopedia Astronautica. http://www.astronautix.com/craft/shuuang1.htm. Retrieved March 4, 2009.
- ^ a b "神八2010年首飞 运载火箭将有重大变化(组图)". 凤凰资讯. June 26, 2008. http://news.ifeng.com/mil/2/200806/0626_340_617870_3.shtml. Retrieved July 8, 2008.
- ^ Spacecraft - Shenzhou
- ^ a b "Russian capabilities circa 1970 - as a comparison to current Chinese space capabilities". http://www.russianspaceweb.com/spacecraft_manned_salyut.html. Retrieved 30 June 2007.
- ^ "神七挑战前所未有 “神八”飞船开始研制". 人民网. March 3, 2008. http://scitech.people.com.cn/GB/25892/6948873.html. Retrieved September 9, 2008.
- ^ "神七太空行走或着"中国制造"出舱服". 解放网. April 10, 2008. http://www.jfdaily.com/gb/jfxww/xinwen/node1221/node45536/userobject1ai2002217.html. Retrieved April 24, 2008.
- ^ "我国现役和研制中的卫星与飞船谱系图". 虚幻天空. June 4, 2008. http://www.war-sky.com/forum/attachment/Day_080607/18_119674_65305d9e5a8ed68.jpg. Retrieved June 7, 2008.
- ^ "中国航天器太空对接效果图". 虚幻天空. June 21, 2008. http://i0.sinaimg.cn/jc/p/2008-06-19/U1335P27T1D505932F3DT20080619081931.jpg. Retrieved June 23, 2008.
- ^ "China will launch small space station in 2010-2011 (in Chinese)". 2008-09-29. http://news.sina.com.cn/c/2008-09-29/145316381853.shtml.
- "Shenzhou". http://www.astronautix.com/craft/shenzhou.htm. Retrieved 21 July 2005.
- "China's first astronaut revealed". BBC. March 7, 2003. http://news.bbc.co.uk/1/hi/sci/tech/2829349.stm.
- "Brief history of Russian aid to Chinese space program". http://www.cns.miis.edu/pubs/week/031006.htm. Retrieved 7 June 2007.
- "Details on purchase of Soyuz descent capsule by China, Space.com". http://www.space.com/news/china_russia_991122.html. Retrieved 7 June 2007.
[edit] External links
- Flickr: Photos tagged with shenzhou, photos likely relating to Shenzhou spacecraft
- Mission highlights of Shenzhou 7
- Subsystems and Project management of Shenzhou 7
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