The International Space Station in 2007

A space station is an artificial structure designed for humans to live in outer space. Human beings, humans or man (Origin 1590–1600 L homō man OL hemō the earthly one (see Humus Outer space, often simply called space, comprises the relatively empty regions of the Universe outside the escape velocities of Celestial bodies. So far only low earth orbit (LEO) stations are implemented, also known as orbital stations. A Low Earth Orbit (LEO is generally defined as an Orbit within the locus extending from the Earth’s surface up to an altitude of 2000 km A space station is distinguished from other manned spacecraft by its lack of major propulsion or landing facilities — instead, other vehicles are used as transport to and from the station. A spacecraft is a Vehicle or machine designed for Spaceflight. Spacecraft propulsion is any method used to change the velocity of Spacecraft and artificial Satellites There are many different methods Landing is the last part of a Flight, where a flying Animal, Aircraft, or Spacecraft returns to the ground Space stations are designed for medium-term living in orbit, for periods of weeks, months, or even years. In Physics, an orbit is the gravitationally curved path of one object around a point or another body for example the gravitational orbit of a planet around a star A week (also called sennight or sevennight) is a unit of Time longer than a Day and shorter than a Month. The month is a unit of Time, used with Calendars which is approximately as long as some natural period related to the motion of the Moon; A year (from Old English gēr) is the time between two recurrences of an event related to the Orbit of the Earth around the Sun The only space station currently in use is the International Space Station. Previous ones are the Almaz, Salyut series, Skylab and Mir. The Almaz (Алмаз - "Diamond" program was a series of military Space stations (or "Orbital Piloted Station" - OPS launched by the Soviet Union The Salyut program (Салют lit  Salute or Fireworks) was the first Space station program undertaken by the Soviet Union, which consisted Skylab was the first Space station the United States launched into orbit and the second space station ever visited by a human crew Mir (Мир which can mean both Peace and World, and was the name given to peasant communes in pre-revolutionary Russia was a Soviet (and

Space stations are currently (as of 2007) used to study the effects of long-term space flight on the human body as well as to provide platforms for greater number and length of scientific studies than available on other space vehicles. Since the ill-fated flight of Soyuz 11 to Salyut 1, all manned spaceflight duration records have been set aboard space stations. Soyuz 11 was the first successful visit to the world's first Space station, Salyut 1. Salyut 1 (DOS-1 ( Салют-1; English translation Salute 1) was the first space station of any kind and the first Soviet Space station The duration record of 437. 7 days was set by Valeriy Polyakov aboard Mir from 1994 to 1995. Valeriy Vladimirovich Polyakov (Валерий Владимирович Поляков Valeriy Vladmirovich Polyakov) (born April 27, 1942) is a Russian Mir (Мир which can mean both Peace and World, and was the name given to peasant communes in pre-revolutionary Russia was a Soviet (and As of 2008, three astronauts have completed single missions of over a year, all aboard Mir. 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common

Uses

Space stations have been used for both military and civilian purposes. The last military-use space station was Salyut 5, which was used by the Almaz program of the Soviet Union in 1976 and 1977. Salyut 5 (OPS-3 (Салют-5 Salute V/5 was launched on June 22, 1976 from the Baikonur Cosmodrome aboard a Proton 8K82K rocket. The Almaz (Алмаз - "Diamond" program was a series of military Space stations (or "Orbital Piloted Station" - OPS launched by the Soviet Union The Union of Soviet Socialist Republics (USSR was a constitutionally Socialist state that existed in Eurasia from 1922 to 1991 ^[1]

Types of space stations

Monolithic

Broadly speaking, the space stations so far launched have been of two types; the earlier stations, Salyut and Skylab, have been "monolithic", intended to be constructed and launched in one piece, and then manned by a crew later. The Salyut program (Салют lit  Salute or Fireworks) was the first Space station program undertaken by the Soviet Union, which consisted Skylab was the first Space station the United States launched into orbit and the second space station ever visited by a human crew As such, they generally contained all their supplies and experimental equipment when launched, and were considered "expended", and then abandoned, when these were used up.

Starting with Salyut 6 and Salyut 7, a change was seen; these were built with two docking ports, which allowed a second crew to visit, bringing a new spacecraft with them (for technical reasons, a Soyuz capsule cannot safely spend more than a few months in orbit, even powered down). Salyut 6 (Салют-6 lit  Salute 6) was a Soviet orbital space station, the eighth flown as part of the Salyut programme. Salyut 7 (Салют-7 Salute 7 was the final Space station launched into Low Earth orbit as part of the Soviet Union 's Salyut Program Design A Soyuz spacecraft consists of three parts (from front to back A Spheroid Orbital module, which provides accommodation for the crew during This allowed for a crew to man the station continually. Skylab was also equipped with two docking ports, like second-generation stations, but the extra port was never utilized. Skylab was the first Space station the United States launched into orbit and the second space station ever visited by a human crew The presence of a second port on the new stations allowed Progress supply vehicles to be docked to the station, meaning that fresh supplies could be brought to aid long-duration missions. This concept was expanded on Salyut 7, which "hard docked" with a TKS tug shortly before it was abandoned; this served as a proof-of-concept for the use of modular space stations. Design The TKS spacecraft is composed of TKS SAS TKS SAS for "Sistema avariynogo spaseniya" or "Emergency escape system" The later Salyuts may reasonably be seen as a transition between the two groups.

Modular

The second group, Mir and the ISS, have been modular; a core unit was launched, and additional modules, generally with a specific role, were later added to that. Mir (Мир which can mean both Peace and World, and was the name given to peasant communes in pre-revolutionary Russia was a Soviet (and (On Mir they were usually launched independently, whereas on the ISS most are brought by the Shuttle). This method allows for greater flexibility in operation, as well as removing the need for a single immensely powerful launch vehicle. These stations are also designed from the outset to have their supplies provided by logistical support, which allows for a longer lifetime at the cost of requiring regular support launches.

Habitability issues

These stations have various issues that limit their long-term habitability, such as very low recycling rates, relatively high radiation levels and a lack of gravity. Some of these problems cause discomfort and long-term health effects. In the case of solar flares, all current habitats are protected by the Earth's magnetic field, and are below the Van Allen belts. The Van Allen radiation belt is a Torus of energetic Charged particles ( plasma) around Earth, held in place by Earth's Magnetic

Future space habitats may attempt to address these issues, and are intended for long-term occupation. A space habitat, also called space colony, orbital colony, space city, or space settlement is a Space station intended as a Some designs might even accommodate large numbers of people, essentially "cities in space" where people would make their homes. A city is an Urban area with a large Population and a particular Administrative, Legal, or Historical status No such design has yet been constructed, because even for a small station, the extra equipment is too expensive to place in orbit at current (2008) launch costs.

Possible ways to deal with these costs would be building lots of rockets (economies of scale), reusable rockets, In Situ Resource Utilisation or if space elevators are ever able to be constructed. In Space exploration, In-Situ Resource Utilization (ISRU describes the proposed use of resources found or manufactured on other planetary bodies (the Moon Mars etc A space elevator is a proposed structure designed to transport Material from a celestial body 's Surface into space.

Architecture

A space station is a complex system with many subsystems. These subsystems are interrelated in a medium or large sense; thus, each subsystem is designed considering the others. All of these subsystems should be safe and function reliably.

The main subsystems of a space station are:

1. Structure
2. Electric energy
3. Termical control
4. Navigation and orientation control
5. Propulsion
6. Automation and robotics
7. Informatics and communications
8. Environmental control and fluids distribution
9. Lodging and other services for crew
10. Crew and loads transport

Past and present space stations

(dates refer to periods when stations were inhabited by crews)

• Salyut space stations (USSR, 1971-1986)
  • Salyut 1 (1971, 1 crew and 1 failed docking)
  • DOS-2 (1972, launch failure)
  • Salyut 2/Almaz (1973, failed shortly after launch)
  • Cosmos 557 (1973, re-entered eleven days after launch)
  • Salyut 3/Almaz (1974, 1 crew and 1 failed docking)
  • Salyut 4 (1975, 2 crews)
  • Salyut 5/Almaz (1976-1977, 2 crews and 1 failed docking)
  • Salyut 6 (1977-1981, 16 crews (5 long duration, 11 short duration and 1 failed docking)
  • Salyut 7 (1982-1986, 10 crews (6 long duration, 4 short duration and 1 failed docking)

• Skylab space station (USA, 1973-1974, 3 crews)

• Mir space station (USSR/Russia, 1986-2000, 28 long duration crews)

• International Space Station (ISS) (USA, Russia, Japan, European Space Agency, Canada, Brazil, Italy 2000-ongoing, 17 long duration crews to date)

Following the controlled deorbiting of Mir in 2001, the International Space Station is the only one of these currently in orbit; it has been continuously occupied since October 30, 2000. The Salyut program (Салют lit  Salute or Fireworks) was the first Space station program undertaken by the Soviet Union, which consisted Salyut 1 (DOS-1 ( Салют-1; English translation Salute 1) was the first space station of any kind and the first Soviet Space station Salyut 2 (OPS-1 (Салют-2 Salute 2 was launched April 4, 1973. The Almaz (Алмаз - "Diamond" program was a series of military Space stations (or "Orbital Piloted Station" - OPS launched by the Soviet Union The Salyut space station that Almaz had substituted for designated DOS 3, was launched on May 11, 1973, three days before the launch of Skylab Salyut 3 (OPS-2 (Салют-3 Salute 3 was launched on June 25, 1974. Salyut 4 (DOS 4 (Салют-4 English translation Salute 4) was a Salyut Space station launched on December 26, 1974 Salyut 5 (OPS-3 (Салют-5 Salute V/5 was launched on June 22, 1976 from the Baikonur Cosmodrome aboard a Proton 8K82K rocket. Salyut 6 (Салют-6 lit  Salute 6) was a Soviet orbital space station, the eighth flown as part of the Salyut programme. Salyut 7 (Салют-7 Salute 7 was the final Space station launched into Low Earth orbit as part of the Soviet Union 's Salyut Program Skylab was the first Space station the United States launched into orbit and the second space station ever visited by a human crew Mir (Мир which can mean both Peace and World, and was the name given to peasant communes in pre-revolutionary Russia was a Soviet (and This is a list of expeditions to the Mir Space Station. Unless otherwise stated crew members are from the bloc of countries comprising the former Soviet Union This is a list of a permanent crews assigned to the International Space Station (ISS. Events 637 - Antioch surrenders to the Muslim forces under Rashidun Caliphate after the Battle of Iron bridge. 2000 ( MM) was a Leap year that started on Saturday of the Common Era, in accordance with the Gregorian calendar. As of 9 September 2006, it was 44. Events 1000 - Battle of Svolder, Viking Age. 1379 - Treaty of Neuberg, splitting the Austrian Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. 5 metres (146 ft) in length along the core between the Destiny and Zvezda modules or 52 metres (171 ft) long when a Progress is attached, and has a mass of 183. 3 metric tons (202. This article is about the tonne or metric ton For other tons see Ton. 1 short tons). The short ton ( S/T) is a unit of mass equal to 2000 lb (around 907

List of occupied space stations, with statistics

Space station	Image	Launched	Reentered	Days in use		Total crew and visitors	Visits		Mass (kg)
				In orbit	Occupied		Manned	Unmanned
Salyut 1		Apr 19, 1971 01:40:00 UTC	Oct 11, 1971	175	24	3	2	0	18,425 kg (40,620 lb)
Skylab		May 14, 1973 17:30:00 UTC	Jul 11, 1979 16:37:00 UTC	2,249	171	9	3	0	77,088 kg (169,950 lb)
Salyut 3		Jun 25, 1974 22:38:00 UTC	Jan 24, 1975	213	15	2	1	0	18,500 kg (40,786 lb)
Salyut 4		Dec 26, 1974 04:15:00 UTC	Feb 3, 1977	770	92	4	2	1	18,500 kg (40,786 lb)
Salyut 5		Jun 22, 1976 18:04:00 UTC	Aug 8, 1977	412	67	4	2	0	19,000 kg (41,888 lb)
Salyut 6		Sep 29, 1977 06:50:00 UTC	Jul 29, 1982	1,764	683	33	16	14	19,000 kg (41,888 lb)
Salyut 7		Apr 19, 1982 19:45:00 UTC	Feb 7, 1991	3,216	816	26	12	15	19,000 kg (41,888 lb)
Mir		Feb 19, 1986 21:28:23 UTC	Mar 23, 2001 05:50:00 UTC	5,511	4,594	137	39	68	124,340 kg (274,123 lb)
ISS		Nov 20, 1998	Currently in orbit Projected 2016	†3,429	†2,753	†158	†41	†32	†286,876 kg (632,453 lb)

Crew and visitors counting is non-distinct. Salyut 1 (DOS-1 ( Салют-1; English translation Salute 1) was the first space station of any kind and the first Soviet Space station Skylab was the first Space station the United States launched into orbit and the second space station ever visited by a human crew Salyut 3 (OPS-2 (Салют-3 Salute 3 was launched on June 25, 1974. Salyut 4 (DOS 4 (Салют-4 English translation Salute 4) was a Salyut Space station launched on December 26, 1974 Salyut 5 (OPS-3 (Салют-5 Salute V/5 was launched on June 22, 1976 from the Baikonur Cosmodrome aboard a Proton 8K82K rocket. Salyut 6 (Салют-6 lit  Salute 6) was a Soviet orbital space station, the eighth flown as part of the Salyut programme. Salyut 7 (Салют-7 Salute 7 was the final Space station launched into Low Earth orbit as part of the Soviet Union 's Salyut Program Mir (Мир which can mean both Peace and World, and was the name given to peasant communes in pre-revolutionary Russia was a Soviet (and

• †ISS stats as of April 10, 2008. Events 879 - Louis III becomes King of the Western Franks. 1407 - the lama 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common
• †ISS stats as of April 10, 2008. Events 879 - Louis III becomes King of the Western Franks. 1407 - the lama 2008 ( MMVIII) is the current year in accordance with the Gregorian calendar, a Leap year that started on Tuesday of the Common _{25 shuttles, 16 Soyuz, 28 Progress, 1 ATV, 3 automated modules}

Canceled space stations

Gemini B reentry module separates from the MOL. 1967 conceptual drawing using Gemini reentry spacecraft. (USAF)

Space Station Freedom Concept (1984)

• A second Skylab unit (Skylab B) was manufactured, as a backup article; due to the high costs of providing launch vehicles, and a desire by NASA to cease Saturn and Apollo operations in time to prepare for the Space Shuttle coming into service, it was never flown. Skylab B was a concept for a second US Space station similar to Skylab that was planned to be launched by NASA for different purposes mostly NASA 's Space Shuttle, officially called the Space Transportation System ( STS) is the Spacecraft currently used by the United States The hull can now be seen in the National Air and Space Museum, in Washington DC, where it is a popular tourist attraction. The National Air and Space Museum (NASM of the Smithsonian Institution is a museum in Washington D

• A number of additional Salyuts were produced, as backups or as flight articles that were later canceled. The Salyut program (Салют lit  Salute or Fireworks) was the first Space station program undertaken by the Soviet Union, which consisted

• The U. S. Space Station Freedom program, which - despite being under development for ten years - was never launched, evolved into the International Space Station

• The Soviet/Russian Mir-2 station, which was never constructed, had some of its elements incorporated into the International Space Station. Original proposal In the early 1980s with the Space shuttle completed NASA proposed the creation of a large permanently manned space station which then-NASA-Administrator Mir -2 was a Space station project begun in February 1976 Some of the modules built for Mir -2 have been incorporated into the International Space Station

• The Industrial Space Facility was a station proposed in the 1980s that was to be privately funded. Space Industries Incorporated was a company formed in the 1980s for the purpose of building a privately owned Space station, which was to be called the Industrial Space Facility The project was canceled when the company created to build it, Space Industries Incorporated, was unable to secure funding from the United States government. Space Industries Incorporated was a company formed in the 1980s for the purpose of building a privately owned Space station, which was to be called the Industrial Space Facility The federal government of the United States is the central United States Governmental body established by the United States Constitution. ^[2]

• United States Air Force Manned Orbiting Laboratory project, canceled in 1969 about a year before the first planned test flight; this was unusual in being an explicitly military project, as opposed to the Soviet Almaz program, which was heavily intertwined with - and concealed by - the contemporaneous Salyut program. The Manned Orbital Laboratory ( MOL) was part of the United States Air Force 's Manned spaceflight program a successor to the cancelled X-20 Dyna-Soar The Almaz (Алмаз - "Diamond" program was a series of military Space stations (or "Orbital Piloted Station" - OPS launched by the Soviet Union

• The European Columbus project planned to create a small space station serviced by the Hermes shuttle. Hermes was a proposed mini-shuttle designed by the French Centre national d'études spatiales ( CNES) in 1975, and later by the European Space Agency It evolved into the ISS Columbus module. Columbus is a science laboratory that is part of the International Space Station (ISS and is the largest single contribution to the ISS made by the European

Future developments

• Currently, Bigelow Aerospace is developing commercial inflatable habitat modules, derived from the earlier NASA Transhab concept, intended to be used for space station construction and for a space prize they are funding and operating, America's Space Prize. Bigelow Aerospace is a North Las Vegas Nevada space technology Startup company that is pioneering work on expandable Space station modules Transhab was a concept pursued by NASA to develop the technology for expandable habitats inflated by air in space America's Space Prize is a US$ 50 million Space competition in Orbital spaceflight established and funded by hotel entrepreneur Robert Bigelow Genesis I and Genesis II are ⅓-scale unmanned prototype modules orbited to test the feasibility of inflatable structures and other systems in space. Genesis I is an experimental space habitat designed and built by the private American firm Bigelow Aerospace and launched in 2006 Genesis II is the second experimental space habitat designed and built by the private American firm Bigelow Aerospace, and was launched in 2007 Future modules include the Galaxy, Sundancer and BA 330, each being progressively larger and more complicated, with the BA 330 intended as the full-scale manned production model for Bigelow's expandable space habitation module program. Galaxy (previously Guardian) is a canceled prototype Space habitat designed by the American firm Bigelow Aerospace Sundancer is the proposed third prototype Space habitat to be launched by Bigelow Aerospace and the first human-rated inflatable module based on the The BA 330 (previously known as the Nautilus space complex module) is the complete full-scale production model of Bigelow Aerospace 's expandable space habitation
• Project 921-2 is the working name given by the People's Republic of China for plans to create a manned space station by 2012. Project 921 is the working name given by the People's Republic of China in 1992 for plans to create a manned Space station. Talk People's Republic of China) PEOPLE'S REPUBLIC OF CHINA ARTICLE GUIDELINES
• In April 2008, the Russian space agency has proposed the construction of an orbital construction yard for spacecraft too heavy to launch from Earth directly. It would not begin construction or be finished until after the decommission of the International Space Station^[3].

References

Bibliography

See also

• Kerim Kerimov, lead architect behind earliest space stations
• Lunar space elevator
• Space colonization
• Space stations in popular culture
• Space habitat

External links

• Read Congressional Research Service (CRS) Reports regarding Space Stations
• Space Station Newsgroup - sci.space.station
• List of Science Fiction Space Stations
• Associated Press International Space Station Timeline Interactive