Obverse view in November 2021
|
|
International Space Station program emblem with flags of the original signatory states[1]
|
|
| Station statistics | |
|---|---|
| COSPAR ID | 1998-067A |
| SATCAT no. | 25544 |
| Call sign | Alpha, Station |
| Crew |
|
| Launch | 20 November 1998[b] |
| Launch pad | |
| Mass | 450,000 kg (990,000 lb)[4] |
| Length | 109 m (358 ft) (overall), 94 m (310 ft) (truss)[5] |
| Width | 73 m (239 ft) (solar array)[5] |
| Pressurised volume | 1,005.0 m3 (35,491 cu ft)[5] |
| Atmospheric pressure | 1 atm (101.3 kPa; 14.7 psi) 79% nitrogen, 21% oxygen |
| Perigee altitude | 413 km (256.6 mi) AMSL[6] |
| Apogee altitude | 422 km (262.2 mi) AMSL[6] |
| Orbital inclination | 51.64°[6] |
| Orbital speed | 7.67 km/s; 27,600 km/h; 17,100 mph[7] |
| Orbital period | 92.9 minutes[8] |
| Orbits per day | 15.5[6] |
| Orbit epoch | 16 August 16:19:30[9] |
| Days in orbit | 27 years, 7 months, 21 days as of 11 July 2026 |
| Days occupied | 25 years, 8 months, 9 days as of 11 July 2026 |
| No. of orbits | 157,366 as of 29 June 2026[9] |
| Orbital decay | 2 km/month (1.2 mi/month) |
| Statistics as of 22 December 2022 (unless noted otherwise) References:[5][6][10][11][12] |
|
| Configuration | |
Station elements as of 2023
(exploded view with the names of elements coloured by country) |
|
The International Space Station (ISS)[c] is a space station in low Earth orbit (LEO). It is the product of the International Space Station program and is operated by five partner space agencies: NASA (United States), Roscosmos (Russia), ESA (Europe), JAXA (Japan), and CSA (Canada).[13] It is the first space station built, maintained and crewed through international cooperation and the largest human spacecraft ever constructed.[14][15] It is an orbital research station, where scientific experiments in microgravity are conducted and the space environment is studied.[15] Since 2 November 2000, it has hosted the longest continuous presence of humans in space.[16] Alongside Tiangong, it is one of the only two currently operational space stations.[17]
The station orbits between 51.64° north and south, at about 400 kilometres (250 miles)[18] above Earth, below the Van Allen radiation belts and most space debris.[19] Its orbit takes it at 7.67 km/s (27,600 km/h; 17,200 mph) roughly every 93 minutes around Earth, 15.5 times a day.[20] Measuring 109 m (358 ft) (with solar arrays) by 73 m (239 ft),[21] it is as large as a full-sized football or soccer field,[22] and has a pressurised internal volume of 1,005 m3 (35,491 ft3), comparable to a Boeing 747 airliner.[21]
The station is a modular space station divided into two main sections: the Russian Orbital Segment (ROS), developed by Roscosmos, and the US Orbital Segment (USOS), built by NASA, ESA, JAXA, and CSA. The Integrated Truss Structure connects the station’s vast system of solar panels and radiators to its 16 major pressurized modules. These modules support scientific research, crew habitation, storage, spacecraft control, and airlock operations. The ISS has eight docking and berthing ports for visiting spacecraft. In total, the station consists of 43 different modules and elements.[23] Crews visit via the Soyuz and Crew Dragon spacecraft, and previously the Space Shuttle.[d] Cargo supply craft include Progress, Cargo Dragon, Cygnus, Automated Transfer Vehicle, and HTV-X.
The ISS is the political product of the development of international cooperation in space throughout the space age. The station combines two previously planned crewed Earth-orbiting stations: the United States’ Space Station Freedom and the Soviet Union’s Mir-2. The first ISS module was launched in 1998, with major components delivered by Proton, Soyuz and Space Shuttle launch vehicles. Long-term occupancy began with the arrival of the Expedition 1 crew on 2 November 2000. Since then, the ISS has remained continuously inhabited for 25 years and 251 days, the longest continuous human presence in space. As of August 2025, 290 individuals from 26 countries had visited the station.[24]
Future plans for the ISS include the addition of at least one module, the Payload Power Thermal Module by Axiom Space, forming the commercial segment of the station. The station is expected to remain operational until the end of 2030, by which parts of it are to be used for Axiom Station and the Russian Orbital Service Station. After this the ISS is planned to be de-orbited using the US Deorbit Vehicle,[25] but critique of this plan and the proposal of parking the station at a more stable higher orbit has gathered congressional support as of 2026.
Conception
Early into the space age and ensuing space race the US and USSR began to find opportunities for potential collaborations in outer space. This culminated in the 1975 Apollo–Soyuz Test Project, the first docking of spacecraft from two different spacefaring nations. The ASTP was considered a success, and further joint missions were also contemplated.
One such concept was International Skylab, which proposed launching the backup Skylab B space station for a mission that would see multiple visits by both Apollo and Soyuz crew vehicles.[26] More ambitious was the Skylab-Salyut Space Laboratory, which proposed docking the Skylab B to a Soviet Salyut space station. Falling budgets and rising Cold War tensions in the late 1970s saw these concepts fall by the wayside, along with another plan to have the Space Shuttle dock with a Salyut space station.[27]
In the early 1980s, NASA planned to launch a modular space station called Freedom as a counterpart to the Salyut and Mir space stations. In 1984 the European Space Agency (ESA) was invited to participate in Space Station Freedom, and the ESA approved the Columbus laboratory by 1987.[28] The Japanese Experiment Module (JEM), or Kibō, was announced in 1985, as part of the Freedom space station in response to a NASA request in 1982.
In early 1985, science ministers from the ESA countries approved the Columbus program, the most ambitious effort in space undertaken by that organization at the time. The plan spearheaded by Germany and Italy included a module which would be attached to Freedom, and with the capability to evolve into a full-fledged European orbital outpost before the end of the century.[29]
Increasing costs threw these plans into doubt in the early 1990s. Congress was unwilling to provide enough money to build and operate Freedom, and demanded NASA increase international participation to defray the rising costs or they would cancel the entire project outright.[30]
Simultaneously, the USSR was conducting planning for the Mir-2 space station, and had begun constructing modules for the new station by the mid-1980s. However the collapse of the Soviet Union required these plans to be greatly downscaled, and soon Mir-2 was in danger of never being launched at all.[31] With both space station projects in jeopardy, American and Russian officials met and proposed they be combined.[32]
In September 1993, American Vice-President Al Gore and Russian Prime Minister Viktor Chernomyrdin announced plans for a new space station, which eventually became the International Space Station.[33] They also agreed, in preparation for this new project, that the United States would be involved in the Mir program, including American Shuttles docking, in the Shuttle–Mir program.[34]
Purpose
The ISS was originally intended to be a laboratory, observatory, and factory while providing transportation, maintenance, and a low Earth orbit staging base for possible future missions to the Moon, Mars, and asteroids. However, not all of the uses envisioned in the initial memorandum of understanding between NASA and Roscosmos have been realised.[35] In the 2010 United States National Space Policy, the ISS was given additional roles of serving commercial, diplomatic,[36] and educational purposes.[37]
Scientific research
The ISS provides a platform to conduct scientific research, with power, data, cooling, and crew available to support experiments. Small uncrewed spacecraft can also provide platforms for experiments, especially those involving zero gravity and exposure to space, but space stations offer a long-term environment where studies can be performed potentially for decades, with ready access by human researchers.[38][39]
The ISS simplifies individual experiments by allowing groups of experiments to share the same launches and crew time. Research is conducted in a wide variety of fields, including astrobiology, astronomy, physical sciences, materials science, space weather, meteorology, and human research including space medicine and the life sciences.[40][41][42][43] Scientists on Earth have timely access to the data and can suggest experimental modifications to the crew. If follow-on experiments are necessary, the routinely scheduled launches of resupply craft allows new hardware to be launched with relative ease.[39] Crews fly expeditions of several months’ duration, providing approximately 160 man-hours per week of labour with a crew of six. However, a considerable amount of crew time is taken up by station maintenance.[44]
A notable ISS experiment is the Alpha Magnetic Spectrometer (AMS), which is intended to detect dark matter and answer other fundamental questions about the universe. According to NASA, the AMS is as important as the Hubble Space Telescope. It is docked on the station, and could not have been easily accommodated on a free flying satellite platform because of its power and bandwidth needs.[45][46] On 3 April 2013, scientists reported that hints of dark matter may have been detected by the AMS.[47][48][49][50][51][52] According to these scientists, “The first results from the space-borne Alpha Magnetic Spectrometer confirm an unexplained excess of high-energy positrons in Earth-bound cosmic rays”.[53]
The space environment is hostile to life. Unprotected presence in space results in exposure to intense radiation (consisting primarily of protons and other subatomic charged particles from the solar wind, in addition to cosmic rays), vacuum, extreme temperatures, and microgravity.[54] Some simple forms of life called extremophiles,[55] as well as small invertebrates called tardigrades,[56] can survive in this environment in an extremely dry state through desiccation.
Medical research improves knowledge about the effects of long-term space exposure on the human body, including muscle atrophy, bone loss, and fluid shift. This data will be used to determine whether long-lasting human spaceflight and space colonisation is feasible. In 2006, data on bone loss and muscular atrophy suggested that there would be a significant risk of fractures and movement problems if astronauts landed on a planet after a lengthy interplanetary cruise, such as the six-month interval required to travel to Mars.[57][58][needs update]
Medical studies are conducted aboard the ISS on behalf of the National Space Biomedical Research Institute (NSBRI). Prominent among these is the Advanced Diagnostic Ultrasound in Microgravity study in which astronauts perform ultrasound scans under the guidance of remote experts. The study considers the diagnosis and treatment of medical conditions in space. There is usually no physician on board the ISS and diagnosis of medical conditions is a challenge. It is anticipated that remotely guided ultrasound scans will have application on Earth in emergency and rural care situations where in-person access to a trained physician is difficult.[59][60][61]
In August 2020, scientists reported that bacteria from Earth, particularly Deinococcus radiodurans bacteria, which is highly resistant to environmental hazards, were found to survive for three years in outer space, based on studies conducted on the International Space Station. These findings supported the notion of panspermia, the hypothesis that life exists throughout the Universe, distributed in various ways, including space dust, meteoroids, asteroids, comets, planetoids or contaminated spacecraft.[62][63]
Remote sensing of the Earth, astronomy, and deep space research on the ISS have significantly increased during the 2010s after the completion of the US Orbital Segment in 2011. Throughout the more than 20 years of the ISS program, researchers aboard the ISS and on the ground have examined aerosols, ozone, lightning, and oxides in Earth’s atmosphere, as well as the Sun, cosmic rays, cosmic dust, antimatter, and dark matter in the universe. Examples of Earth-viewing remote sensing experiments that have flown on the ISS are the Orbiting Carbon Observatory 3, ISS-RapidScat, ECOSTRESS, the Global Ecosystem Dynamics Investigation, and the Cloud Aerosol Transport System. ISS-based astronomy telescopes and experiments include SOLAR, the Neutron Star Interior Composition Explorer, the Calorimetric Electron Telescope, the Monitor of All-sky X-ray Image (MAXI), and the Alpha Magnetic Spectrometer.[40][64]
Microgravity environment
Researchers are investigating the effect of the station’s near-weightless environment on the evolution, development, growth and internal processes of plants and animals. In response to some of the data, NASA wants to investigate microgravity‘s effects on the growth of three-dimensional, human-like tissues and the unusual protein crystals that can be formed in space.[40]
Investigating the physics of fluids in microgravity will provide better models of the behaviour of fluids. Because fluids can be almost completely combined in microgravity, physicists investigate fluids that do not mix well on Earth. Examining reactions that are slowed by low gravity and low temperatures will improve our understanding of superconductivity.[40]
The study of materials science is an important ISS research activity, with the objective of reaping economic benefits through the improvement of techniques used on Earth.[65] Other areas of interest include the effect of low gravity on combustion, through the study of the efficiency of burning and control of emissions and pollutants. These findings may improve knowledge about energy production and lead to economic and environmental benefits.[40]
Exploration
The ISS provides a location in the relative safety of low Earth orbit to test spacecraft systems that will be required for long-duration missions to the Moon and Mars. This provides experience in operations, maintenance, and repair and replacement activities on-orbit. This will help develop essential skills in operating spacecraft farther from Earth, reduce mission risks, and advance the capabilities of interplanetary spacecraft.[66] Referring to the MARS-500 experiment, a crew isolation experiment conducted on Earth, ESA states, “Whereas the ISS is essential for answering questions concerning the possible impact of weightlessness, radiation and other space-specific factors, aspects such as the effect of long-term isolation and confinement can be more appropriately addressed via ground-based simulations”.[67] Sergey Krasnov, the head of human space flight programs for Russia’s space agency, Roscosmos, in 2011 suggested a “shorter version” of MARS-500 may be carried out on the ISS.[68]
In 2009, noting the value of the partnership framework itself, Sergey Krasnov wrote, “When compared with partners acting separately, partners developing complementary abilities and resources could give us much more assurance of the success and safety of space exploration. The ISS is helping further advance near-Earth space exploration and realisation of prospective programs of research and exploration of the Solar system, including the Moon and Mars.”[69] A crewed mission to Mars may be a multinational effort involving space agencies and countries outside the current ISS partnership. In 2010, ESA Director-General Jean-Jacques Dordain stated his agency was ready to propose to the other four partners that China, India, and South Korea be invited to join the ISS partnership.[70] NASA chief Charles Bolden stated in February 2011, “Any mission to Mars is likely to be a global effort.”[71] Currently, US federal legislation prevents NASA co-operation with China on space projects without approval by the FBI and Congress.[72]
Education and cultural outreach
The ISS crew provides opportunities for students on Earth by running student-developed experiments, making educational demonstrations, allowing for student participation in classroom versions of ISS experiments, and directly engaging students using radio, and email.[73][74] ESA offers a wide range of free teaching materials that can be downloaded for use in classrooms.[75] In one lesson, students can navigate a 3D model of the interior and exterior of the ISS, and face spontaneous challenges to solve in real time.[76]
The Japanese Aerospace Exploration Agency (JAXA) aims to inspire children to “pursue craftsmanship” and to heighten their “awareness of the importance of life and their responsibilities in society”.[77] Through a series of education guides, students develop a deeper understanding of the past and near-term future of crewed space flight, as well as that of Earth and life.[78][79] In the JAXA “Seeds in Space” experiments, the mutation effects of spaceflight on plant seeds aboard the ISS are explored by growing sunflower seeds that have flown on the ISS for about nine months. In the first phase of Kibō utilisation from 2008 to mid-2010, researchers from more than a dozen Japanese universities conducted experiments in diverse fields.[80]
Cultural activities are another major objective of the ISS program. Tetsuo Tanaka, the director of JAXA’s Space Environment and Utilization Center, has said: “There is something about space that touches even people who are not interested in science.”[81]
Amateur Radio on the ISS (ARISS) is a volunteer program that encourages students worldwide to pursue careers in science, technology, engineering, and mathematics, through amateur radio communications opportunities with the ISS crew. ARISS is an international working group, consisting of delegations from nine countries including several in Europe, as well as Japan, Russia, Canada, and the United States. In areas where radio equipment cannot be used, speakerphones connect students to ground stations which then connect the calls to the space station.[82] Other licensed operators are able to contact the station freely via various methods, including NFM , APRS and SSTV (Only during events, and downlink only)[83]
First Orbit is a 2011 feature-length documentary film about Vostok 1, the first crewed space flight around the Earth. By matching the orbit of the ISS to that of Vostok 1 as closely as possible, in terms of ground path and time of day, documentary filmmaker Christopher Riley and ESA astronaut Paolo Nespoli were able to film the view that Yuri Gagarin saw on his pioneering orbital space flight. This new footage was cut together with the original Vostok 1 mission audio recordings sourced from the Russian State Archive. Nespoli is credited as the director of photography for this documentary film, as he recorded the majority of the footage himself during Expedition 26/27.[84] The film was streamed in a global YouTube premiere in 2011 under a free licence through the website firstorbit.org.[85]
In May 2013, commander Chris Hadfield shot a music video of David Bowie‘s “Space Oddity” on board the station, which was released on YouTube.[86][87] It was the first music video filmed in space.[88]
In November 2017, while participating in Expedition 52/53 on the ISS, Paolo Nespoli made two recordings of his spoken voice (one in English and the other in his native Italian), for use on Wikipedia articles. These were the first content made in space specifically for Wikipedia.[89][90]
In November 2021, a virtual reality exhibit called The Infinite featuring life aboard the ISS was announced.[91]
International co-operation
Involving five space programs and fifteen countries,[92] the International Space Station is the most politically and legally complex space exploration program in history.[92] The 1998 Space Station Intergovernmental Agreement sets forth the primary framework for international cooperation among the parties. A series of subsequent agreements govern other aspects of the station, ranging from jurisdictional issues to a code of conduct among visiting astronauts.[93]
Brazil was also invited to participate in the program, the only developing country to receive such an invitation. Under the agreement framework, Brazil was to provide six pieces of hardware, and in exchange, would receive ISS utilization rights. However, Brazil was unable to deliver any of the elements due to a lack of funding and political priority within the country. Brazil officially dropped out of the ISS program in 2007.[94][95]
Following the 2022 Russian invasion of Ukraine, continued cooperation between Russia and other countries on the International Space Station has been put into question. Roscosmos Director General Dmitry Rogozin insinuated that Russian withdrawal could cause the International Space Station to de-orbit due to lack of reboost capabilities, writing in a series of tweets, “If you block cooperation with us, who will save the ISS from an unguided de-orbit to impact on the territory of the US or Europe? There’s also the chance of impact of the 500-ton construction in India or China. Do you want to threaten them with such a prospect? The ISS doesn’t fly over Russia, so all the risk is yours. Are you ready for it?”[96] (This latter claim is untrue: the ISS flies over all parts of the Earth between 51.6 degrees latitude north and south, approximately the latitude of Saratov.) Rogozin later tweeted that normal relations between ISS partners could only be restored once sanctions have been lifted, and indicated that Roscosmos would submit proposals to the Russian government on ending cooperation.[97] NASA stated that, if necessary, US corporation Northrop Grumman has offered a reboost capability that would keep the ISS in orbit.[98]
On 26 July 2022, Yury Borisov, Rogozin’s successor as head of Roscosmos, submitted to Russian President Vladimir Putin plans for withdrawal from the program after 2024.[99] However, Robyn Gatens, the NASA official in charge of the space station, responded that NASA had not received any formal notices from Roscosmos concerning withdrawal plans.[100]
Participating countries:
Canada
European Space Agency
Japan
Russia
United States:
.
GOOGLE PRIVACY POLICY
Effective Date: 2026-06-02.
https://canadarms.com/ and https://ecommercesuperstore.ca/ is OWNED BY >17986815 CANADA COROPATION, https://canadarms.com/ and https://ecommercesuperstore.ca/ and its affiliates or “we” in this Google Privacy Policy) know how important privacy is to our customers. This Privacy Policy applies to all of our https://canadarms.com/ and https://ecommercesuperstore.ca/ that are under the 17986815 CANADA COROPATION PRIVACY POLICY and services where we process personal information, from mobile phones, tablets, and home appliances, to the customer services and online services we provide on our https://canadarms.com/ and https://ecommercesuperstore.ca/is under the 17986815 CANADA COROPATION OF CANADA Website PRIVACY POLICY . We will refer to these custoumers and services as the “Services” in this Privacy Policy.
It is important that you check back often for updates to the Privacy Policy. We may update this Privacy Policy periodically to reflect changes in our personal information practices with respect to the Services or changes in applicable law. We will post a notice on our website or on your device to notify you in advance of material changes to our Privacy Policy and indicate at the top of the Privacy Policy when it was most recently updated. The most current version of the Privacy Policy will always be available here: https://www. canadarms.com/account/privacy-policy. CANADARMS.COM is under the 17986815 CANADA COROPATION:
• HOW DO WE USE YOUR INFORMATION?WHAT THIRD-PARTY SERVICES DO WE USE?
Some of the content, advertising, and functionality in our Services is provided by third parties. These third parties may use cookies, beacons, tracking pixels, and other tools to collect information about your use of these Services. These third parties are not controlled directly by https://canadarms.com/ and https://ecommercesuperstore.ca/ is owned under the 17986815 CANADA COROPATION OF CANADA PRIVACY POLICY
Effective Date:2026-06-02>GOOGLE PRIVACY POLICY and services where we process personal information, from mobile phones, tablets, and home appliances, to the customer services and online services we provide . We will post a notice on our website or on your device to notify you in advance of material changes to our Privacy Policy and indicate at the top of the Privacy Policy when it was most recently updated. The most current version of the Privacy Policy will always be available here: https://www. canadarms.COM/account/privacy-policy.
For some apps and services, including social networks, we receive and store sign-in information, as well as other information that you allow us to receive when you connect with these apps and services.
We, along with certain third parties such as content providers and advertisers, use technologies called cookies, beacons, or pixels, as well as other tools (collectively known as “technologies”) that communicate information from your device to a server, including those owned by third parties. These technologies can be embedded in online content, videos, and advertisements.
Effective Date: 2026-06-02 , so we recommend that you check their privacy policies to understand how they use your data.
For some apps and services, including social networks, we receive and store sign-in information, as well as other information that you allow us to receive when you connect with these apps and services.Effective Date: 2026-06-02.
https://canadarms.com/ and https://ecommercesuperstore.ca/ is OWNED BY >17986815 CANADA COROPATION.
