International Space Station

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**History and Purpose**:
– US and USSR contemplated collaborations post-space race.
– 1975 Apollo-Soyuz Test Project led to further joint missions.
– Various concepts like International Skylab and Skylab-Salyut Space Laboratory were proposed.
– In the early 1980s, NASA planned to launch Space Station Freedom.
– In 1993, plans for the ISS were announced by American Vice-President Al Gore and Russian Prime Minister Viktor Chernomyrdin.
– ISS intended as a laboratory, observatory, and factory.
– Serves as a staging base for future missions to the Moon, Mars, and asteroids.
– Additional roles include commercial, diplomatic, and educational purposes.
– US National Space Policy in 2010 expanded the ISS’s roles.

**Scientific Research and Exploration**:
– ISS provides a platform for scientific research.
– Offers power, data, cooling, and crew support for experiments.
– Allows for long-term studies potentially lasting decades.
– Facilitates research in various fields like astrobiology, astronomy, and materials science.
– Enables human research in space medicine and life sciences.
– ISS tests spacecraft systems for long-duration missions to the Moon and Mars.
– Experience gained in operations, maintenance, and repair activities on-orbit.
– ISS helps develop essential skills for operating spacecraft farther from Earth.
– Partnerships and collaborations in space exploration enhance success and safety.

**Construction and Manufacturing**:
– ISS assembled and maintained in low Earth orbit by five space agencies.
– Divided into Russian and US Orbital Segments.
– Features the Integrated Truss Structure connecting modules.
– Specialized pressurized modules for research, habitation, and storage.
– Visiting spacecraft dock at the station via eight ports.
– ISS components were manufactured in various countries for in-orbit assembly.
– U.S. components like Destiny and Unity were fabricated at Marshall Space Flight Center.
– Russian modules Zarya and Zvezda were manufactured at the Khrunichev Center in Moscow.
– ESA’s Columbus module was manufactured in Bremen, Germany.
– Japanese Experiment Module Kibō was fabricated in Japan.

**Life in Space and Cultural Activities**:
– Extremophiles and tardigrades can survive in space.
– Medical research on ISS studies effects of long-term space exposure on the human body.
– Advanced Diagnostic Ultrasound in Microgravity study helps diagnose medical conditions.
– Bacteria like Deinococcus radiodurans can survive in outer space.
Research supports the panspermia hypothesis of life in the Universe.
– ISS program includes cultural activities.
– ARISS encourages students to pursue STEM careers.
– Music video Space Oddity by Chris Hadfield was the first filmed in space.
– Documentary First Orbit recreated Yuri Gagarin’s view during Vostok 1.
– Paolo Nespoli made spoken voice recordings for Wikipedia in space.

**Modules and Components**:
– Zarya Module: First module launched for ISS assembly.
– Unity Module: First U.S.-built component connecting Russian and U.S. segments.
– Zvezda Module: Provides life support systems and living quarters for two crew members.
– Destiny Module: Primary operating facility for U.S. research payloads on ISS.
– Poisk Module: Launched on 10 November 2009, used as the Russian airlock module.
– Harmony Module: Utility hub of the ISS providing electrical power and electronic data.
– Tranquility Module: Contains environmental control systems and a toilet, launched on STS-130 in February 2010.

The International Space Station (ISS) is a large space station assembled and maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United States), Roscosmos (Russia), JAXA (Japan), ESA (Europe), and CSA (Canada). The ISS is the largest space station ever built. Its primary purpose is to perform microgravity and space environment experiments.

International Space Station (ISS)
A forward view of the International Space Station with limb of the Earth in the background. In view are the station's sixteen paired maroon-coloured main solar array wings, eight on either side of the station, mounted to a central integrated truss structure. Spaced along the truss are ten white radiators. Mounted to the base of the two rightmost main solar arrays pairs, there are two smaller paired light brown-coloured ISS Roll-out Solar Arrays. Attached to the centre of the truss is a cluster of pressurised modules arranged in an elongated T shape. A set of solar arrays are mounted to the module at the aft end of the cluster.
Oblique underside view in November 2021
International Space Station program insignia, with flags of the original signatory states.
Station statistics
COSPAR ID1998-067A
SATCAT no.25544
Call signAlpha, Station
Launch20 November 1998 (25 years ago) (1998-11-20)
Launch pad
Mass450,000 kg (990,000 lb)
Length109 m (358 ft) (overall length), 94 m (310 ft) (truss length)
Width73 m (239 ft) (solar array length)
Pressurised volume1,005.0 m3 (35,491 cu ft)
Atmospheric pressure101.3 kPa (14.7 psi; 1.0 atm)
79% nitrogen, 21% oxygen
Perigee altitude413 km (256.6 mi) AMSL
Apogee altitude422 km (262.2 mi) AMSL
Orbital inclination51.64°
Orbital speed7.67 km/s; 27,600 km/h; 17,100 mph
Orbital period92.9 minutes
Orbits per day15.5
Orbit epoch16 August 16:19:30
Days in orbit25 years, 6 months, 25 days
(14 June 2024)
Days occupied23 years, 7 months, 12 days
(14 June 2024)
No. of orbits141,117 as of August 2023
Orbital decay2 km/month
Statistics as of 22 December 2022
(unless noted otherwise)
The components of the ISS in an exploded diagram, with modules on-orbit highlighted in orange.
Station elements as of December 2022
(exploded view)

Operationally, the station is divided into two sections: the Russian Orbital Segment (ROS) assembled by Roscosmos, and the US Orbital Segment, assembled by NASA, JAXA, ESA and CSA. A striking feature of the ISS is the Integrated Truss Structure, which connects the large solar panels and radiators to the pressurized modules. The pressurized modules are specialized for research, habitation, storage, spacecraft control, and airlock functions. Visiting spacecraft dock at the station via its eight docking and berthing ports. The ISS maintains an orbit with an average altitude of 400 kilometres (250 mi) and circles the Earth in roughly 93 minutes, completing 15.5 orbits per day.

The ISS programme combines two prior plans to construct crewed Earth-orbiting stations: Space Station Freedom planned by the United States, and the Mir-2 station, planned by the Soviet Union. The first ISS module was launched in 1998. Major modules have been launched by Proton and Soyuz rockets and by the Space Shuttle launch system. The first long-term residents, Expedition 1, arrived on November 2, 2000. Since then, the station has been continuously occupied for 23 years and 225 days, the longest continuous human presence in space. As of March 2024, 279 individuals from 22 countries have visited the space station. The ISS is expected to have additional modules (the Axiom Orbital Segment, for example) before being de-orbited by a dedicated NASA spacecraft in January 2031.

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