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• and • ≈ 419,455 kg (924,740 lb) Length 72.8 m (239 ft) Width 108.5 m (356 ft) Height ≈ 20 m (66 ft) nadir–zenith, arrays forward–aft (27 November 2009) [ ] Pressurised 931.57 m 3 (32,898 cu ft) (28 May 2016) 101.3 (29.9; 1.0 ) 401.1 km (249.2 mi) 408.0 km (253.5 mi) Orbital 51.64 Orbital speed 7.67 km/s (27,600 km/h; 17,200 mph) 92.65 minutes Orbits per day 15.54 Orbit 7 July 2017, 13:10:09 UTC Days in orbit 19 years, 1 month, 4 days (24 December 2017) Days occupied 17 years, 1 month, 22 days (24 December 2017) No. Of orbits 102,491 as of July 2017 2 km/month Statistics as of 9 March 2011 (unless noted otherwise) References: Configuration. Station elements as of June 2017 () The International Space Station ( ISS) is a, or a habitable, in. Its first component launched into orbit in 1998, the last pressurised module was fitted in 2011, and the station is expected to be used until 2028. Development and assembly of the station continues, with components scheduled for launch in 2018 and 2019. The ISS is the largest human-made body in low Earth orbit and can often be seen with the from Earth. The ISS consists of pressurised modules, external trusses,, and other components.

ISS components have been launched by Russian and rockets, and American. The ISS serves as a and research laboratory in which crew members conduct experiments in,,,,, and. The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars.

The ISS of between 330 and 435 km (205 and 270 mi) by means of reboost manoeuvres using the engines of the module or visiting spacecraft. It completes 15.54 orbits per day.

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The is a joint project among five participating space agencies:,,,, and. The ownership and use of the space station is established by intergovernmental treaties and agreements. The station is divided into two sections, the (ROS) and the (USOS), which is shared by many nations. As of January 2014, the American portion of ISS is being funded until 2024. Roscosmos has endorsed the continued operation of ISS through 2024 but has proposed using elements of the Russian Orbital Segment to construct a new Russian space station called.

The ISS is the ninth space station to be inhabited by crews, following the Soviet and later Russian,, and stations as well as from the US. The station has been continuously occupied for 000000000♠17 years and 52 days since the arrival of on 2 November 2000. This is the longest continuous human presence in, having surpassed the previous record of 000000000♠9 years and 357 days held by Mir. The station is serviced by a variety of visiting spacecraft: the Russian and, the American and, the Japanese, and formerly the and the European. It has been visited by astronauts, cosmonauts and space tourists from.

After the U.S. Programme ended in 2011, Soyuz rockets became the only provider of transport for astronauts at the International Space Station, and Dragon became the only provider of bulk cargo return to Earth (called ). Soyuz has very limited downmass capability. On 28 March 2015, Russian sources announced that Roscosmos and NASA had agreed to collaborate on the development of a replacement for the current ISS. NASA later issued a guarded statement expressing thanks for Russia's interest in future co-operation in space exploration but fell short of confirming the Russian announcement. Are deployed by the attached to the end of the Japanese robotic arm According to the original Memorandum of Understanding between NASA and Rosaviakosmos, the International Space Station was intended to be a laboratory, observatory and factory in.

It was also planned to provide transportation, maintenance, and act as a staging base for possible future missions to the Moon, Mars and asteroids. In the 2010 United States National Space Policy, the ISS was given additional roles of serving commercial, diplomatic and educational purposes. Scientific research. Main article: The ISS provides a platform to conduct scientific research.

Small unmanned spacecraft can provide platforms for zero gravity and exposure to space, but space stations offer a long-term environment where studies can be performed potentially for decades, combined with ready access by human researchers over periods that exceed the capabilities of manned spacecraft. The ISS simplifies individual experiments by eliminating the need for separate rocket launches and research staff.

The wide variety of research fields include,, including and,,,, and weather on Earth (). Scientists on Earth have access to the crew's data and can modify experiments or launch new ones, which are benefits generally unavailable on unmanned spacecraft.

Crews fly of several months duration, providing approximately 160-man-hours per week of labour with a crew of 6. To detect dark matter and answer other fundamental questions about our universe, engineers and scientists from all over the world built the (AMS), which NASA compares to the, and says could not be accommodated on a free flying satellite platform partly because of its power requirements and data bandwidth needs. On 3 April 2013, scientists reported that hints of may have been detected by the Alpha Magnetic Spectrometer. According to the scientists, ' from the space-borne Alpha Magnetic Spectrometer confirm an unexplained excess of high-energy positrons in Earth-bound cosmic rays.' The space environment is hostile to life. Unprotected presence in space is characterised by an intense radiation field (consisting primarily of protons and other subatomic charged particles from the, in addition to ), high vacuum, extreme temperatures, and microgravity. Some simple forms of life called, including small invertebrates called can survive in this environment in an extremely dry state called.

Medical research improves knowledge about the effects of long-term space exposure on the human body, including,, and fluid shift. This data will be used to determine whether lengthy and are feasible. As of 2006, data on bone loss and muscular atrophy suggest 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. Medical studies are conducted aboard the ISS on behalf of the (NSBRI). Prominent among these is the 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. Usually, there is 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 access to a trained physician is difficult. A comparison between the combustion of a candle on (left) and in a microgravity environment, such as that found on the ISS (right) The Earth's gravity is only slightly weaker at the altitude of the ISS than at the surface, but objects in orbit are in a continuous state of, resulting in an apparent state of weightlessness. This perceived weightlessness is disturbed by five separate effects: • Drag from the residual atmosphere; when the ISS enters the Earth's shadow, the main solar panels are rotated to minimise this aerodynamic drag, helping reduce. • Vibration from movements of mechanical systems and the crew. • Actuation of the on-board attitude. • firings for attitude or orbital changes. •, also known as effects.

Items at different locations within the ISS would, if not attached to the station, follow slightly different orbits. Being mechanically interconnected these items experience small forces that keep the station moving as a. ISS crew member storing samples 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 this data, NASA wants to investigate 's effects on the growth of three-dimensional, human-like tissues, and the unusual that can be formed in space. 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. In addition, examining reactions that are slowed by low gravity and low temperatures will improve our understanding of.

The study of is an important ISS research activity, with the objective of reaping economic benefits through the improvement of techniques used on the ground. Other areas of interest include the effect of the low gravity environment on combustion, through the study of the efficiency of burning and control of emissions and pollutants. These findings may improve current knowledge about energy production, and lead to economic and environmental benefits. Future plans are for the researchers aboard the ISS to examine,,, and in Earth's atmosphere, as well as,,, and in the universe.

A 3D plan of the Russia-based complex, used for ground-based experiments which complement ISS-based preparations for a 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 and. This provides experience in operations, maintenance as well as repair and replacement activities on-orbit, which will be essential skills in operating spacecraft farther from Earth, mission risks can be reduced and the capabilities of interplanetary spacecraft advanced. Referring to the experiment, ESA states that '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'. Sergey Krasnov, the head of human space flight programmes for Russia's space agency, Roscosmos, in 2011 suggested a 'shorter version' of MARS-500 may be carried out on the ISS. 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 programmes of research and exploration of the Solar system, including the Moon and 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.

NASA chief stated in February 2011, 'Any mission to Mars is likely to be a global effort'. Currently, American legislation prevents NASA co-operation with China on space projects. Education and cultural outreach. Japan's berthing 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, videolink and email.

ESA offers a wide range of free teaching materials that can be downloaded for use in classrooms. In one lesson, students can navigate a 3-D model of the interior and exterior of the ISS, and face spontaneous challenges to solve in real time. JAXA aims both to 'Stimulate the curiosity of children, cultivating their spirits, and encouraging their passion to pursue craftsmanship', and to 'Heighten the child's awareness of the importance of life and their responsibilities in society.' Through a series of education guides, a deeper understanding of the past and near-term future of manned space flight, as well as that of Earth and life, will be learned. In the JAXA Seeds in Space experiments, the mutation effects of spaceflight on plant seeds aboard the ISS is explored.

Students grow sunflower seeds which flew on the ISS for about nine months as a start to 'touch the Universe'. 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.

Original Jules Verne manuscripts displayed by crew inside Jules Verne ATV Cultural activities are another major objective. Tetsuo Tanaka, director of JAXA's Space Environment and Utilization Center, says 'There is something about space that touches even people who are not interested in science.'

(ARISS) is a volunteer programme which encourages students worldwide to pursue careers in science, technology, engineering and mathematics through communications opportunities with the ISS crew. ARISS is an international working group, consisting of delegations from nine countries including several countries 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 station. Is a feature-length documentary film about, the first manned space flight around the Earth.

By matching the orbit of the International Space Station 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 were able to film the view that 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, during Expedition 26/27, filmed the majority of the footage for this documentary film, and as a result is credited as its.

The film was streamed through the website firstorbit.org in a global YouTube premiere in 2011, under a free license. In May 2013, commander shot a music video of 's ' on board the station; the film was released on YouTube. It was the first music video ever to be filmed in space. ISS in 2009, with S6 truss added The assembly of the International Space Station, a major endeavour in, began in November 1998. Russian modules launched and docked robotically, with the exception of.

All other modules were delivered by the Space Shuttle, which required installation by ISS and shuttle crewmembers using the (SSRMS) and (EVAs); as of 5 June 2011, they had added 159 components during more than 1,000 hours of EVA (see ). 127 of these spacewalks originated from the station, and the remaining 32 were launched from the airlocks of docked Space Shuttles. The of the station had to be considered at all times during construction, as it directly affects how long during its orbit the station (and any docked or docking spacecraft) is exposed to the sun; the Space Shuttle would not perform optimally above a limit called the 'beta cutoff'. Many of the modules that launched on the Space Shuttle were at the to find and correct issues prior to launch. The first module of the ISS,, was launched on 20 November 1998 on an autonomous Russian. It provided propulsion,, communications, electrical power, but lacked long-term life support functions.

Two weeks later, a passive NASA module was launched aboard Space Shuttle flight and attached to Zarya by astronauts during EVAs. This module has two (PMAs), one connects permanently to Zarya, the other allows the Space Shuttle to dock to the space station. At that time, the Russian station Mir was still inhabited.

The ISS remained unmanned for two years, while Mir was de-orbited. On 12 July 2000, was launched into orbit. Preprogrammed commands on board deployed its solar arrays and communications antenna.

It then became the passive target for a rendezvous with Zarya and Unity: it maintained a station-keeping orbit while the Zarya- Unity vehicle performed the rendezvous and docking via ground control and the Russian automated rendezvous and docking system. Zarya 's computer transferred control of the station to Zvezda 's computer soon after docking. Zvezda added sleeping quarters, a toilet, kitchen, CO 2 scrubbers, dehumidifier, oxygen generators, exercise equipment, plus data, voice and television communications with mission control. This enabled permanent habitation of the station.

The first resident crew,, arrived in November 2000 on. At the end of the first day on the station, astronaut Bill Shepherd requested the use of the radio call sign ' Alpha', which he and cosmonaut Krikalev preferred to the more cumbersome ' International Space Station'.

The name ' Alpha' had previously been used for the station in the early 1990s, and following the request, its use was authorised for the whole of Expedition 1. Shepherd had been advocating the use of a new name to project managers for some time. Referencing a in a pre-launch news conference he had said: 'For thousands of years, humans have been going to sea in ships. People have designed and built these vessels, launched them with a good feeling that a name will bring good fortune to the crew and success to their voyage.'

, the President of at the time, disapproved of the name ' Alpha'; he felt that Mir was the first space station, and so he would have preferred the names ' Beta' or ' Mir 2' for the ISS. Arrived midway between the flights of and. These two Space Shuttle flights each added segments of the station's, which provided the station with Ku-band communication for US television, additional attitude support needed for the additional mass of the USOS, and substantial supplementing the station's existing 4 solar arrays. Over the next two years, the station continued to expand. A rocket delivered the. The Space Shuttles Discovery,, and Endeavour delivered the and, in addition to the station's main robot arm, the, and several more segments of the Integrated Truss Structure.

The expansion schedule was interrupted by the in 2003 and a resulting two-year hiatus in the. The space shuttle was grounded until 2005 with flown by Discovery. Assembly resumed in 2006 with the arrival of with Atlantis, which delivered the station's second set of solar arrays.

Several more truss segments and a third set of arrays were delivered on,, and. As a result of the major expansion of the station's power-generating capabilities, more pressurised modules could be accommodated, and the node and Columbus European laboratory were added. These were soon followed by the first two components of Kibō. In March 2009, completed the Integrated Truss Structure with the installation of the fourth and final set of solar arrays. The final section of Kibō was delivered in July 2009 on, followed by the Russian module.

The third node,, was delivered in February 2010 during by the Space Shuttle Endeavour, alongside the, followed in May 2010 by the penultimate Russian module,. Rassvet was delivered by Space Shuttle Atlantis on in exchange for the Russian Proton delivery of the Zarya module in 1998 which had been funded by the United States. The last pressurised module of the USOS, Leonardo, was brought to the station by Discovery on her final flight,, in February 2011.

The was delivered by Endeavour on the same year. As of June 2011, the station consisted of 15 pressurised modules and the.

Five modules are still to be launched, including the with the, the, and two power modules called and NEM-2. As of August 2017, Russia's future primary research module Nauka is set to launch in the first quarter of 2018, along with the European Robotic Arm which will be able to relocate itself to different parts of the Russian modules of the station. After the Nauka module is attached, the Uzlovoy Module will be attached to one of its docking ports. When completed, the station will have a mass of more than 400 tonnes (440 short tons). The gross mass of the station changes over time. The total launch mass of the modules on orbit is about 417,289 kg (919,965 lb) (as of 3 September 2011). The mass of experiments, spare parts, personal effects, crew, foodstuff, clothing, propellants, water supplies, gas supplies, docked spacecraft, and other items add to the total mass of the station.

Hydrogen gas is constantly vented overboard by the oxygen generators. Station structure. The ISS is a third generation modular space station. Modular stations can allow the mission to be changed over time and new modules can be added or removed from the existing structure, allowing greater flexibility. Below is a diagram of major station components. The blue areas are pressurised sections accessible by the crew without using spacesuits.

The station's unpressurised superstructure is indicated in red. Other unpressurised components are yellow. Note that the Unity node joins directly to the Destiny laboratory. Wavelab 5 Windows 7 Fix Download.

For clarity, they are shown apart.,, robotic arm robotic arm External payloads Comparison The ISS follows and series,, and as the 11th space station launched, as the prototypes were never intended to be manned. Other examples of modular station projects include the Soviet/Russian Mir and the planned Russian and.

First generation space stations, such as early Salyuts and NASA's Skylab were not designed for re-supply. Generally, each crew had to depart the station to free the only docking port for the next crew to arrive, Skylab had more than one docking port but was not designed for resupply.

And had more than one docking port and were designed to be resupplied routinely during crewed operation. Pressurised modules.

Also known as Node 2, is the second of the station's node modules and the utility hub of the USOS. The module contains four racks that provide electrical power, bus electronic data, and acts as a central connecting point for several other components via its six Common Berthing Mechanisms (CBMs). The European Columbus and Japanese Kibō laboratories are permanently berthed to the starboard and port radial ports respectively. The nadir and zenith ports can be used for docking visiting spacecraft including HTV, Dragon, and Cygnus, with the nadir port serving as the primary docking port. American Shuttle Orbiters docked with the ISS via PMA-2, attached to the forward port.

Tranquility, also known as Node 3, is the third and last of the station's US nodes, it contains an additional life support system to recycle waste water for crew use and supplements oxygen generation. Like the other US nodes, it has six berthing mechanisms, five of which are currently in use. The first one connects to the station's core via the module, others host the, the #3, the and the. The final zenith port remains free.

Columbus module in 2008, the primary research facility for European payloads aboard the ISS, provides a as well as facilities specifically designed for, and. Several mounting locations are affixed to the exterior of the module, which provide power and data to external experiments such as the (EuTEF),,, and. A number of expansions are planned for the module to study and. ESA's development of technologies on all the main areas of life support has been ongoing for more than 20 years and are/have been used in modules such as Columbus and the ATV. The German Aerospace Center manages ground control operations for Columbus and the ATV is controlled from the French.

Not large enough for crew using spacesuits, the airlock on Kibō has a sliding drawer for external experiments. (: きぼう, ') is a laboratory and the largest ISS module. It is used for research in space medicine, biology, Earth observations, materials production, biotechnology and communications, and has facilities for growing plants and fish. During August 2011, the observatory mounted on Kibō, which uses the ISS's orbital motion to image the whole sky in the X-ray spectrum, detected for the first time the moment when a star was swallowed by a black hole. The laboratory contains 23 racks, including 10 experiment racks, and has a dedicated airlock for experiments. In a 'shirt sleeves' environment, crew attach an experiment to the sliding drawer within the airlock, close the inner, and then open the outer hatch. By extending the drawer and removing the experiment using the dedicated robotic arm, payloads are placed on the external platform.

The process can be reversed and repeated quickly, allowing access to maintain external experiments without the delays caused by EVAs. Remote Manipulator System A smaller pressurised module is attached to the top of Kibō, serving as a cargo bay. The dedicated Interorbital Communications System (ICS) allows large amounts of data to be beamed from Kibō 's ICS, first to the Japanese KODAMA satellite in geostationary orbit, then to Japanese ground stations.

When a direct communication link is used, contact time between the ISS and a ground station is limited to approximately 10 minutes per visible pass. When KODAMA relays data between a LEO spacecraft and a ground station, real-time communications are possible in 60% of the flight path of the spacecraft. Japanese ground controllers use to remotely conduct onboard research and experiments, thus reducing the workload of station astronauts.

Ground controllers also use a free-floating autonomous to photodocument astronaut and space station activities, further freeing up astronaut time. The cancelled Habitation module under construction in 1997 Cancelled components Several modules planned for the station were cancelled over the course of the ISS programme. Reasons include budgetary constraints, the modules becoming unnecessary, and station redesigns after the 2003.

The US would have hosted science experiments in varying levels of. The US would have served as the station's living quarters.

Instead, the sleep stations are now spread throughout the station. The US and would have replaced the functions of Zvezda in case of a launch failure. Two were planned for scientific research. They would have docked to a Russian. The Russian would have supplied power to the independent of the ITS solar arrays. Unpressurised elements. ISS Truss Components breakdown showing Trusses and all ORUs in situ The ISS has a large number of external components that do not require pressurisation.

The largest of these is the (ITS), to which the station's main solar arrays and thermal radiators are mounted. The ITS consists of ten separate segments forming a structure 108.5 m (356 ft) long. The station in its complete form has several smaller external components, such as the six robotic arms, the three (ESPs) and four (ELCs). While these platforms allow experiments (including, the STP-H3 and the ) to be deployed and conducted in the vacuum of space by providing electricity and processing experimental data locally, their primary function is to store spare (ORUs). ORUs are parts that can be replaced when they fail or pass their design life. Examples of ORUs include pumps, storage tanks, antennas and battery units.

Such units are replaced either by astronauts during EVA or by robotic arms. Spare parts were routinely transported to and from the station via Space Shuttle resupply missions, with a heavy emphasis on ORU transport once the NASA Shuttle approached retirement. Several shuttle missions were dedicated to the delivery of ORUs, including, and. As of January 2011, only one other mode of transportation of ORUs had been utilised – the Japanese cargo vessel – which delivered an FHRC and CTC-2 via its Exposed Pallet (EP). Construction of the over New Zealand. There are also smaller exposure facilities mounted directly to laboratory modules; the Kibō serves as an external ' for the Kibō complex, and a facility on the European Columbus laboratory provides power and data connections for experiments such as the and the.

A instrument,, was delivered to the station in 2014 aboard a, and the experiment is scheduled to be delivered in 2016. The largest such scientific payload externally mounted to the ISS is the (AMS), a particle physics experiment launched on in May 2011, and mounted externally on the ITS. The AMS measures to look for evidence of and. Robotic arms and cargo cranes. The interactions between the components of the ISS Environmental Control and Life Support System (ECLSS) The atmosphere on board the ISS is similar to the. Normal air pressure on the ISS is 101.3 (14.7 ); the same as at sea level on Earth.

An Earth-like atmosphere offers benefits for crew comfort, and is much safer than the alternative, a pure oxygen atmosphere, because of the increased risk of a fire such as that responsible for the deaths of the crew. Earth-like atmospheric conditions have been maintained on all Russian and Soviet spacecraft. The system aboard Zvezda and a similar system in Destiny generate oxygen aboard the station.

The crew has a backup option in the form of bottled oxygen and (SFOG) canisters, a system. Carbon dioxide is removed from the air by the system in Zvezda. Other by-products of human metabolism, such as methane from the intestines and ammonia from sweat, are removed by filters.

Part of the ROS atmosphere control system is the oxygen supply. Triple-redundancy is provided by the Elektron unit, solid fuel generators, and stored oxygen. The primary supply of oxygen is the Elektron unit which produces O 2 and H 2 by of water and vents H2 overboard. The 1 kW system uses approximately one litre of water per crew member per day. This water is either brought from Earth or recycled from other systems. Mir was the first spacecraft to use recycled water for oxygen production.

The secondary oxygen supply is provided by burning O 2-producing cartridges (see also ). Each 'candle' takes 5–20 minutes to decompose at 450–500 °C, producing 600 litres of O 2.

This unit is manually operated. The US Orbital Segment has redundant supplies of oxygen, from a pressurised storage tank on the Quest airlock module delivered in 2001, supplemented ten years later by ESA-built Advanced Closed-Loop System (ACLS) in the Tranquility module (Node 3), which produces O 2 by electrolysis. Hydrogen produced is combined with carbon dioxide from the cabin atmosphere and converted to water and methane. Power and thermal control. Double-sided solar, or, arrays provide for the ISS.

These bifacial cells are more efficient and operate at a lower temperature than single-sided cells commonly used on Earth, by collecting sunlight on one side and light the Earth on the other. The Russian segment of the station, like the Space Shuttle and most spacecraft, uses 28 from four rotating solar arrays mounted on Zarya and Zvezda. The USOS uses 130–180 V DC from the USOS PV array, power is stabilised and distributed at 160 V DC and converted to the user-required 124 V DC.

The allows smaller, lighter conductors, at the expense of crew safety. The ROS uses; the two station segments share power with converters.

The USOS solar arrays are arranged as four wing pairs, for a total production of 75 to 90 kilowatts. These arrays normally track the sun to maximise power generation.

Each array is about 375 m 2 (4,036 sq ft) in area and 58 m (190 ft) long. In the complete configuration, the solar arrays track the sun by rotating the alpha once per orbit; the beta gimbal follows slower changes in the angle of the sun to the orbital plane.

The aligns the solar arrays parallel to the ground at night to reduce the significant aerodynamic drag at the station's relatively low orbital altitude. The station uses rechargeable (NiH 2) for continuous power during the 35 minutes of every 90-minute orbit that it is eclipsed by the Earth. The batteries are recharged on the day side of the Earth. They have a 6.5-year lifetime (over 37,000 charge/discharge cycles) and will be regularly replaced over the anticipated 20-year life of the station. As of 2017, the nickel–hydrogen batteries are being replaced by, which are expected to last until the end of the ISS program. The station's large solar panels generate a high potential voltage difference between the station and the ionosphere. This could cause arcing through insulating surfaces and sputtering of conductive surfaces as ions are accelerated by the spacecraft plasma sheath.

To mitigate this, plasma contactor units (PCU)s create current paths between the station and the ambient plasma field. ISS External Active Thermal Control System (EATCS) diagram The station's systems and experiments consume a large amount of electrical power, almost all of which converts to heat. Little of this heat dissipates through the walls of the station. To keep the internal ambient temperature within comfortable, workable limits, is continuously pumped through pipes throughout the station to collect heat, then into external radiators to emit infrared radiation, then back into the station. Thus this passive thermal control system (PTCS) is made of external surface materials, insulation such as MLI, and heat pipes.

If the PTCS cannot keep up with the heat load, an External Active Thermal Control System (EATCS) maintains the temperature. The EATCS consists of an internal, non-toxic, water coolant loop used to cool and dehumidify the atmosphere, which transfers collected heat into an external liquid ammonia loop that can withstand the much lower temperature of space, and is circulated through radiators to remove the heat. The EATCS provides cooling for all the US pressurised modules, including Kibō and Columbus, as well as the main power distribution electronics of the S0, S1 and P1 trusses. It can reject up to 70 kW. This is much more than the 14 kW of the Early External Active Thermal Control System (EEATCS) via the Early Ammonia Servicer (EAS), which was launched on and installed onto the P6 Truss. Communications and computers.

The communications systems used by the ISS * Luch satellite and the Space Shuttle are not currently in use Radio communications provide and scientific data links between the station and. Radio links are also used during and for audio and video communication between crew members, flight controllers and family members. As a result, the ISS is equipped with internal and external communication systems used for different purposes. The Russian Orbital Segment communicates directly with the ground via the mounted to Zvezda. The Lira antenna also has the capability to use the data relay satellite system.

This system, used for communications with Mir, fell into disrepair during the 1990s, and so is no longer in use, although two new Luch satellites— Luch-5A and Luch-5B—were launched in 2011 and 2012 respectively to restore the operational capability of the system. Another Russian communications system is the, which enables internal telephone communications between Zvezda, Zarya, Pirs, Poisk and the USOS, and also provides a VHF radio link to ground control centres via antennas on Zvezda 's exterior.

The (USOS) makes use of two separate radio links mounted in the structure: the (used for audio) and (used for audio, video and data) systems. These transmissions are routed via the United States System (TDRSS) in, which allows for almost continuous real-time communications with (MCC-H) in. Data channels for the Canadarm2, European Columbus laboratory and Japanese Kibō modules are routed via the S band and K u band systems, although the and a similar Japanese system will eventually complement the TDRSS in this role. Communications between modules are carried on an internal digital. Laptop computers surround the Canadarm2 console. Is used by astronauts and cosmonauts conducting. UHF is used by other spacecraft that dock to or undock from the station, such as Soyuz, Progress, HTV, ATV and the Space Shuttle (except the shuttle also makes use of the S band and K u band systems via TDRSS), to receive commands from Mission Control and ISS crewmembers.

Automated spacecraft are fitted with their own communications equipment; the ATV uses a attached to the spacecraft and equipment attached to Zvezda, known as the Proximity Communications Equipment, to accurately dock to the station. The ISS is equipped with approximately 100 and model A31 and T61P laptop computers. Each computer is a purchase which is then modified for safety and operation including updates to connectors, cooling and power to accommodate the station's 28V DC power system and weightless environment. Heat generated by the laptops does not rise but stagnates around the laptop, so additional forced ventilation is required. Laptops aboard the ISS are connected to the station's via and to the ground via K u band. This provides speeds of 10 to and 3 Mbit/s from the station, comparable to home connection speeds.

The operating system used for key station functions is the. The migration from was made in May 2013 for reasons of reliability, stability and flexibility.

Station operations Expeditions and private flights. Expeditions have included crew members from many nations See also the (professional crew), (private travellers), and the (both). Each permanent crew is given an expedition number. Expeditions run up to six months, from launch until undocking, an 'increment' covers the same time period, but includes cargo ships and all activities. Expeditions 1 to 6 consisted of 3 person crews, Expeditions 7 to 12 were reduced to the safe minimum of two following the destruction of the NASA Shuttle Columbia.

From Expedition 13 the crew gradually increased to 6 around 2010. With the arrival of the American vehicles in the middle of the 2010s, expedition size may be increased to seven crew members, the number ISS is designed for., member of and Commander of, has spent more time in space than anyone else, a total of 803 days and 9 hours and 39 minutes. His awards include the,,, and 4 NASA medals.

On 16 August 2005 at 1:44 am EDT, he passed the record of 748 days held by, who had 'time travelled' 1/50th of a second into the future aboard. He participated in psychosocial experiment SFINCSS-99 (Simulation of Flight of International Crew on Space Station), which examined inter-cultural and other stress factors affecting integration of crew in preparation for the ISS spaceflights. Has spent the most time in space of any American. Kelly returned from the ISS on 1 March 2016 having spent 340 consecutive days in orbit. Travellers who pay for their own passage into space are termed spaceflight participants by Roscosmos and NASA, and are sometimes referred to as space tourists, a term they generally dislike.

All seven were transported to the ISS on Russian Soyuz spacecraft. When professional crews change over in numbers not divisible by the three seats in a Soyuz, and a short-stay crewmember is not sent, the spare seat is sold by MirCorp through Space Adventures. When the space shuttle retired in 2011, and the station's crew size was reduced to 6, space tourism was halted, as the partners relied on Russian transport seats for access to the station. Soyuz flight schedules increase after 2013, allowing 5 Soyuz flights (15 seats) with only two expeditions (12 seats) required.

The remaining seats are sold for around US$40 million to members of the public who can pass a medical exam. ESA and NASA criticised private spaceflight at the beginning of the ISS, and NASA initially resisted training, the first man to pay for his own passage to the ISS.

Became the first Iranian in space and the first self-funded woman to fly to the station. Officials reported that her education and experience make her much more than a tourist, and her performance in training had been 'excellent.' Ansari herself dismisses the idea that she is a tourist. She did Russian and European studies involving medicine and microbiology during her 10-day stay. The documentary follows her journey to the station, where she fulfilled 'an age-old dream of man: to leave our planet as a 'normal person' and travel into outer space.' In 2008, spaceflight participant placed a aboard the ISS during his flight. This is currently the only non-terrestrial geocache in existence.

At the same time, the, an electronic record of eight digitised human DNA sequences, was placed aboard the ISS. The ISS is maintained in a nearly circular orbit with a minimum mean altitude of 330 km (205 mi) and a maximum of 410 km (255 mi), in the centre of the, at an of 51.6 degrees to Earth's equator, necessary to ensure that Russian and spacecraft launched from the may be safely launched to reach the station. Spent rocket stages must be dropped into uninhabited areas and this limits the directions rockets can be launched from the spaceport.

It travels at an average speed of 27,724 kilometres per hour (17,227 mph), and completes 15.54 orbits per day (93 minutes per orbit). The station's altitude was allowed to fall around the time of each NASA shuttle mission. Orbital boost burns would generally be delayed until after the shuttle's departure. This allowed shuttle payloads to be lifted with the station's engines during the routine firings, rather than have the shuttle lift itself and the payload together to a higher orbit. This trade-off allowed heavier loads to be transferred to the station.

After the retirement of the NASA shuttle, the nominal orbit of the space station was raised in altitude. Other, more frequent supply ships do not require this adjustment as they are substantially lighter vehicles.

Orbits of the ISS, shown in April 2013 Orbital boosting can be performed by the station's two main engines on the service module, or Russian or European spacecraft docked to Zvezda 's aft port. The ATV has been designed with the possibility of adding a to its other end, allowing it to remain at the ISS and still allow other craft to dock and boost the station. It takes approximately two orbits (three hours) for the boost to a higher altitude to be completed.

Maintaining ISS altitude uses about 7.5 tonnes of chemical fuel per annum at an annual cost of about $210 million. In December 2008 NASA signed an agreement with the which may result in the testing on the ISS of a plasma propulsion engine. This technology could allow to be done more economically than at present. The Russian Orbital Segment contains the Data Management System, which handles Guidance, Navigation and Control (ROS GNC) for the entire station.

Initially, Zarya, the first module of the station, controlled the station until a short time after the Russian service module Zvezda docked and was transferred control. Zvezda contains the ESA built DMS-R Data Management System.

Using two fault-tolerant computers (FTC), Zvezda computes the station's position and orbital trajectory using redundant Earth horizon sensors, Solar horizon sensors as well as Sun and star trackers. The FTCs each contain three identical processing units working in parallel and provide advanced fault-masking by majority voting.

Orientation Zvezda uses gyroscopes and thrusters to turn itself around. Gyroscopes do not require propellant, rather they use electricity to 'store' momentum in flywheels by turning in the opposite direction to the station's movement. The USOS has its own computer controlled gyroscopes to handle the extra mass of that section. When gyroscopes, thrusters are used to cancel out the stored momentum. During, an incorrect command was sent to the station's computer, using about 14 kilograms of propellant before the fault was noticed and fixed. When attitude control computers in the ROS and USOS fail to communicate properly, it can result in a rare 'force fight' where the ROS GNC computer must ignore the USOS counterpart, which has no thrusters. When an ATV, NASA Shuttle, or Soyuz is docked to the station, it can also be used to maintain station attitude such as for troubleshooting.

Shuttle control was used exclusively during of the S3/S4 truss, which provides electrical power and data interfaces for the station's electronics. Mission controls The components of the ISS are operated and monitored by their respective space agencies at across the globe, including: • Roscosmos's at, Moscow Oblast, controls the which handles Guidance, Navigation and Control for the entire Station., in addition to individual Soyuz and Progress missions. • ESA's, at the (CST) in, France, controls flights of the unmanned European.

• JAXA's and at (TKSC) in, Japan, are responsible for operating the Kibō complex and all flights of the 'White Stork' HTV Cargo spacecraft, respectively. • NASA's at in Houston, Texas, serves as the primary control facility for the United States segment of the ISS and also controlled the Space Shuttle missions that visited the station. • NASA's at in, coordinates payload operations in the USOS. • ESA's at the (DLR) in, Germany, manages the European Columbus research laboratory. • CSA's at, Canada, controls and monitors the, or Canadarm2. Spare parts are called; some are externally stored on pallets called and. ( ORUs) are spare parts that can be readily replaced when a unit either passes its design life or fails.

Examples of ORUs are pumps, storage tanks, controller boxes, antennas, and battery units. Some units can be replaced using robotic arms. Many are stored outside the station, either on small pallets called (ELCs) or share larger platforms called which also hold science experiments. Both kinds of pallets have electricity as many parts which could be damaged by the cold of space require heating. The larger logistics carriers also have computer local area network connections (LAN) and telemetry to connect experiments.

A heavy emphasis on stocking the USOS with ORU's occurred around 2011, before the end of the NASA shuttle programme, as its commercial replacements, and, carry one tenth to one quarter the payload. Mike Hopkins on his Christmas Eve spacewalk Unexpected problems and failures have impacted the station's assembly time-line and work schedules leading to periods of reduced capabilities and, in some cases, could have forced abandonment of the station for safety reasons, had these problems not been resolved. During in 2007, following the relocation of the P6 truss and solar arrays, it was noted during the redeployment of the array that it had become torn and was not deploying properly. An EVA was carried out by, assisted. The men took extra precautions to reduce the risk of electric shock, as the repairs were carried out with the solar array exposed to sunlight. The issues with the array were followed in the same year by problems with the starboard Solar Alpha Rotary Joint (SARJ), which rotates the arrays on the starboard side of the station.

Excessive vibration and high-current spikes in the array drive motor were noted, resulting in a decision to substantially curtail motion of the starboard SARJ until the cause was understood. Inspections during EVAs on STS-120 and showed extensive contamination from metallic shavings and debris in the large drive gear and confirmed damage to the large metallic race ring at the heart of the joint, and so the joint was locked to prevent further damage. Repairs to the joint were carried out during with lubrication of both joints and the replacement of 11 out of 12 trundle bearings on the joint. 2009 saw damage to the S1 radiator, one of the components of the station's cooling system. The problem was first noticed in imagery in September 2008, but was not thought to be serious.

The imagery showed that the surface of one sub-panel has peeled back from the underlying central structure, possibly because of micro-meteoroid or debris impact. It is also known that a Service Module thruster cover, jettisoned during an EVA in 2008, had struck the S1 radiator, but its effect, if any, has not been determined. On 15 May 2009 the damaged radiator panel's ammonia tubing was mechanically shut off from the rest of the cooling system by the computer-controlled closure of a valve. The same valve was used immediately afterwards to vent the ammonia from the damaged panel, eliminating the possibility of an ammonia leak from the cooling system via the damaged panel. Early on 1 August 2010, a failure in cooling Loop A (starboard side), one of two external cooling loops, left the station with only half of its normal cooling capacity and zero redundancy in some systems. The problem appeared to be in the ammonia pump module that circulates the ammonia cooling fluid. Several subsystems, including two of the four CMGs, were shut down.

Planned operations on the ISS were interrupted through a series of EVAs to address the cooling system issue. A first EVA on 7 August 2010, to replace the failed pump module, was not fully completed because of an ammonia leak in one of four quick-disconnects. A second EVA on 11 August successfully removed the failed pump module. A third EVA was required to restore Loop A to normal functionality. The USOS's cooling system is largely built by the American company, which is also the manufacturer of the failed pump. An air leak from the USOS in 2004, the venting of fumes from an oxygen generator in 2006, and the failure of the computers in the ROS in 2007 during left the station without thruster, Elektron, and other environmental control system operations, the root cause of which was found to be condensation inside the electrical connectors leading to a short-circuit.

[ ] The four Main Bus Switching Units (MBSUs, located in the S0 truss), control the routing of power from the four solar array wings to the rest of the ISS. In late 2011 MBSU-1, while still routing power correctly, ceased responding to commands or sending data confirming its health, and was scheduled to be swapped out at the next available EVA. In each MBSU, two power channels feed 160V DC from the arrays to two DC-to-DC power converters (DDCUs) that supply the 124V power used in the station. A spare MBSU was already on board, but 30 August 2012 EVA failed to be completed when a bolt being tightened to finish installation of the spare unit jammed before electrical connection was secured. The loss of MBSU-1 limits the station to 75% of its normal power capacity, requiring minor limitations in normal operations until the problem can be addressed. On 5 September 2012, in a second, 6 hr, EVA to replace MBSU-1, astronauts Sunita Williams and Akihiko Hoshide successfully restored the ISS to 100% power. On 24 December 2013, astronauts made a rare Christmas Eve space walk, installing a new ammonia pump for the station's cooling system.

The faulty cooling system had failed earlier in the month, halting many of the station's science experiments. Astronauts had to brave a 'mini blizzard' of ammonia while installing the new pump.

It was only the second Christmas Eve spacewalk in NASA history. Fleet operations. Dragon and Cygnus cargo vessels were docked at the ISS together for the first time in April 2016. A wide variety of manned and unmanned spacecraft have supported the station's activities.

More than 60 Progress spacecraft, including and which installed modules, and more than 40 Soyuz spacecraft have flown to the ISS. 35 flights of the retired NASA Space Shuttle were made to the station. There have been five European, five Japanese, eight and four Orbital ATK flights. Currently docked/berthed See also the list of,, or just. Crewed spacecraft are in light green Spacecraft and mission Location Arrival () Departure (planned) Progress 67 cargo aft 16 June 2017 7 December 2017 / zenith 12 September 2017 27 February 2018 Progress 68 cargo nadir 16 October 2017 March 2018 Dragon CRS-13 cargo nadir 17 December 2017 mid January 2018 / nadir 19 December 2017 3 June 2018 Scheduled missions • All dates are. Dates are the earliest possible dates and may change.

• Forward ports are at the front of the station according to its normal direction of travel and orientation (). Aft is at the rear of the station, used by spacecraft boosting the station's orbit. Is closest the Earth, is on top. • Spacecraft operated by government agencies are indicated with 'Gov' and under commercial arrangements are indicated with 'Com'. Launch date ( NET) Launch vehicle Launch site Launch service provider Payload Spacecraft Mission Docking / berthing port Ref. The resupply vehicle as it approaches the ISS in 2012. Over 50 unpiloted spacecraft have been sent with supplies during the lifetime of the station.

All Russian spacecraft and self-propelled modules are able to rendezvous and dock to the space station without human intervention using the docking system. Radar allows these vehicles to detect and intercept ISS from over 200 kilometres away. The European ATV uses star sensors and GPS to determine its intercept course. When it catches up it uses laser equipment to recognise Zvezda, along with the Kurs system for redundancy. Crew supervise these craft, but do not intervene except to send abort commands in emergencies.

The Japanese parks itself in progressively closer orbits to the station, and then awaits 'approach' commands from the crew, until it is close enough for a robotic arm to grapple and berth the vehicle to the USOS. The American Space Shuttle was manually docked, and on missions with a, the container would be berthed to the Station with the use of manual robotic arms. Berthed craft can transfer.

Japanese spacecraft berth for one to two months. Russian and European Supply craft can remain at the ISS for six months, allowing great flexibility in crew time for loading and unloading of supplies and trash. NASA Shuttles could remain docked for 11–12 days. And docked to the ISS, as seen from the departing The American manual approach to docking allows greater initial flexibility and less complexity. The downside to this mode of operation is that each mission becomes unique and requires specialised training and planning, making the process more labour-intensive and expensive.

The Russians pursued an automated methodology that used the crew in override or monitoring roles. Although the initial development costs were high, the system has become very reliable with standardisations that provide significant cost benefits in repetitive routine operations. An automated approach could allow assembly of modules orbiting other worlds prior to crew arrival.

Soyuz spacecraft used for crew rotation also serve as lifeboats for emergency evacuation; they are replaced every six months and have been used once to remove excess crew after the. Expeditions require, on average, 2,722 kg of supplies, and as of 9 March 2011, crews had consumed a total of around 22,000 meals. Soyuz crew rotation flights and Progress resupply flights visit the station on average two and three times respectively each year, with the ATV and HTV planned to visit annually from 2010 onwards. [ ] and were contracted to fly cargo to the station after retirement of the NASA Shuttle.

From 26 February 2011 to 7 March 2011 four of the governmental partners (United States, ESA, Japan and Russia) had their spacecraft (NASA Shuttle, ATV, HTV, Progress and Soyuz) docked at the ISS, the only time this has happened to date. On 25 May 2012, became the world's first privately held company to send cargo, via the, to the International Space Station. Launch and docking windows Prior to a ship's docking to the ISS, navigation and attitude control (GNC) is handed over to the ground control of the ships' country of origin. GNC is set to allow the station to drift in space, rather than fire its thrusters or turn using gyroscopes. The solar panels of the station are turned edge-on to the incoming ships, so residue from its thrusters does not damage the cells. When a NASA docked to the station, other ships were grounded, as the Shuttle's wing leading edges, cameras, windows, and instruments were too much at risk from damage or contamination by thruster residue from other ships' movements.

Approximately 30% of NASA shuttle launch delays were caused by poor weather. Occasional priority was given to the Soyuz arrivals at the station where the Soyuz carried crew with time-critical cargoes such as biological experiment materials, also causing shuttle delays.

Departure of the NASA shuttle was often delayed or prioritised according to weather over its two landing sites. Whilst the Soyuz is capable of landing anywhere, anytime, its planned landing time and place is chosen to give consideration to helicopter pilots and ground recovery crew, to give acceptable flying weather and lighting conditions.

Soyuz launches occur in adverse weather conditions, but the cosmodrome has been shut down on occasions when buried by snow drifts up to 6 metres in depth, hampering ground operations. Life aboard Crew activities.

Crewmember peers out of a window A typical day for the crew begins with a wake-up at 06:00, followed by post-sleep activities and a morning inspection of the station. The crew then eats breakfast and takes part in a daily planning conference with Mission Control before starting work at around 08:10. The first scheduled exercise of the day follows, after which the crew continues work until 13:05. Following a one-hour lunch break, the afternoon consists of more exercise and work before the crew carries out its pre-sleep activities beginning at 19:30, including dinner and a crew conference. The scheduled sleep period begins at 21:30.

In general, the crew works ten hours per day on a weekday, and five hours on Saturdays, with the rest of the time their own for relaxation or work catch-up. The time zone used aboard the ISS is (UTC). The windows are covered at night hours to give the impression of darkness because the station experiences 16 sunrises and sunsets per day.

During visiting space shuttle missions, the ISS crew mostly follows the shuttle's (MET), which is a flexible time zone based on the launch time of the shuttle mission. The station provides crew quarters for each member of the expedition's crew, with two 'sleep stations' in the Zvezda and four more installed in Harmony. The American quarters are private, approximately person-sized soundproof booths. The Russian crew quarters include a small window, but provide less ventilation and sound proofing.

A crew member can sleep in a crew quarter in a tethered sleeping bag, listen to music, use a laptop, and store personal items in a large drawer or in nets attached to the module's walls. The module also provides a reading lamp, a shelf and a desktop. Visiting crews have no allocated sleep module, and attach a sleeping bag to an available space on a wall. It is possible to sleep floating freely through the station, but this is generally avoided because of the possibility of bumping into sensitive equipment. It is important that crew accommodations be well ventilated; otherwise, astronauts can wake up oxygen-deprived and gasping for air, because a bubble of their own exhaled carbon dioxide has formed around their heads.

See also: Most of the food aboard is vacuum sealed in plastic bags. Cans are rare because they are heavy and expensive to transport. Preserved food is not highly regarded by the crew, and taste is reduced in microgravity. Therefore, effort is made to make the food more palatable, such as using more spices than in regular cooking. The crew looks forward to the arrival of any ships from Earth, as they bring fresh fruit and vegetables. Care is taken that foods do not create crumbs. Sauces are often used to avoid contaminating station equipment.

Each crew member has individual food packages and cooks them using the on-board galley. The galley features two food warmers, a refrigerator added in November 2008, and a water dispenser that provides both heated and unheated water. Drinks are provided as dehydrated powder that is mixed with water before consumption. Drinks and soups are sipped from plastic bags with straws. Solid food is eaten with a knife and fork attached to a tray with magnets to prevent them from floating away. Any food that floats away, including crumbs, must be collected to prevent it from clogging the station's air filters and other equipment.

Space toilet in the service module Showers on space stations were introduced in the early 1970s on Skylab and Salyut 3.: 139 By Salyut 6, in the early 1980s, the crew complained of the complexity of showering in space, which was a monthly activity. The ISS does not feature a shower; instead, crewmembers wash using a water jet and wet wipes, with soap dispensed from a toothpaste tube-like container. Crews are also provided with rinseless shampoo and edible toothpaste to save water.

There are two on the ISS, both of Russian design, located in and. These Waste and Hygiene Compartments use a fan-driven suction system similar to the Space Shuttle Waste Collection System. Astronauts first fasten themselves to the toilet seat, which is equipped with spring-loaded restraining bars to ensure a good seal. A lever operates a powerful fan and a suction hole slides open: the air stream carries the waste away.

Solid waste is collected in individual bags which are stored in an aluminium container. Full containers are transferred to Progress spacecraft for disposal. Liquid waste is evacuated by a hose connected to the front of the toilet, with anatomically correct 'urine funnel adapters' attached to the tube so that men and women can use the same toilet. Is collected and transferred to the Water Recovery System, where it is recycled into drinking water. Crew health and safety. Video of the taken by the crew of on an ascending pass from south of to just north of Australia over the Indian Ocean.

Subatomic charged particles, primarily from and solar wind, are normally absorbed by Earth's atmosphere. When they interact in sufficient quantity, their effect is visible to the naked eye in a phenomenon called an. Outside Earth's atmosphere, crews are exposed to about 1 each day, which is about a year of natural exposure on Earth. This results in a higher risk of cancer for astronauts. Radiation can penetrate living tissue and damage the and of. These cells are central to the, and so any damage to them could contribute to the lower experienced by astronauts. Radiation has also been linked to a higher incidence of in astronauts.

Protective shielding and drugs may lower risks to an acceptable level. Radiation levels on the ISS are about five times greater than those experienced by airline passengers and crew. Earth's electromagnetic field provides almost the same level of protection against solar and other radiation in low Earth orbit as in the stratosphere. For example, on a 12-hour flight an airline passenger would experience 0.1 millisieverts of radiation, or a rate of 0.2 millisieverts per day; only 1/5 the rate experienced by an astronaut in LEO. Additionally, airline passengers experience this level of radiation for a few hours of flight, while ISS crew are exposed for their whole stay. Cosmonaut at work inside service module crew quarters There is considerable evidence that stressors are among the most important impediments to optimal crew morale and performance.

Cosmonaut wrote in his journal during a particularly difficult period on board the space station: 'All the conditions necessary for murder are met if you shut two men in a cabin measuring 18 feet by 20 and leave them together for two months.' NASA's interest in caused by space travel, initially studied when their manned missions began, was rekindled when astronauts joined cosmonauts on the Russian space station Mir. Common sources of stress in early American missions included maintaining high performance under public scrutiny and isolation from peers and family. The latter is still often a cause of stress on the ISS, such as when the mother of NASA Astronaut died in a car accident, and when Michael Fincke was forced to miss the birth of his second child. A study of the longest spaceflight concluded that the first three weeks are a critical period where attention is adversely affected because of the demand to adjust to the extreme change of environment.

Skylab 's three crews remained one, two, and three months respectively, long term crews on Salyut 6,, and the ISS last about five to six months and Mir 's expeditions often lasted longer. The ISS working environment includes further stress caused by living and working in cramped conditions with people from very different cultures who speak a different language. First-generation space stations had crews who spoke a single language; second and third-generation stations have crew from many cultures who speak many languages. The ISS is unique because visitors are not classed automatically into 'host' or 'guest' categories as with previous stations and spacecraft, and may not suffer from feelings of isolation in the same way. Crew members with a military pilot background and those with an academic science background or teachers and politicians may have problems understanding each other's jargon and worldview. Astronaut is attached to the with bungee cords aboard the International Space Station Medical effects of long-term weightlessness include, deterioration of the skeleton, fluid redistribution, a slowing of the cardiovascular system, decreased production of red blood cells, balance disorders, and a weakening of the immune system. Lesser symptoms include loss of body mass, and puffiness of the face.

Sleep is disturbed on the ISS regularly because of mission demands, such as incoming or departing ships. Sound levels in the station are unavoidably high; because the atmosphere is unable to, fans are required at all times to allow processing of the atmosphere which would stagnate in the freefall (zero-g) environment. To prevent some of these adverse effects, the station is equipped with two treadmills (including the ), and the aRED (advanced Resistive Exercise Device) which enables various weightlifting exercises which add muscle but do not compensate for or raise astronauts' reduced bone density, and a stationary bicycle; each astronaut spends at least two hours per day exercising on the equipment. Astronauts use bungee cords to strap themselves to the treadmill.

Microbiological environmental hazards. See also: Hazardous moulds which can foul air and water filters may develop aboard space stations. They can produce acids which degrade metal, glass, and rubber. They can also be harmful for the crew's health. Microbiological hazards have led to a development of the that can identify common bacteria and moulds faster than standard methods of, which may require a sample to be sent back to Earth. As of 2012, 76 types of unregulated micro-organisms have been detected on the ISS. Reduced humidity, paint with mould-killing chemicals, and antiseptic solutions can be used to prevent contamination in space stations.

Telugu Tv Serial Actors Income. All materials used in the ISS are tested for resistance against fungi. Threat of orbital debris. At the low altitudes at which the ISS orbits, there is a variety of space debris, consisting of different objects including entire spent rocket stages, defunct satellites, explosion fragments—including materials from tests, paint flakes, slag from solid rocket motors, and coolant released by nuclear-powered satellites.

These objects, in addition to natural, are a significant threat. Large objects could destroy the station, but are less of a threat because their orbits can be predicted. Objects too small to be detected by optical and radar instruments, from approximately 1 cm down to microscopic size, number in the trillions.

Despite their small size, some of these objects are a threat because of their and direction in relation to the station. Spacesuits of spacewalking crew could puncture, causing. Ballistic panels, also called micrometeorite shielding, are incorporated into the station to protect pressurised sections and critical systems. The type and thickness of these panels depends on their predicted exposure to damage.

The station's shields and structure have different designs on the ROS and the USOS. On the USOS, a thin aluminium sheet is held apart from the hull and causes objects to shatter into a cloud before hitting the hull, thereby spreading the energy of impact.

On the ROS, a carbon plastic honeycomb screen is spaced from the hull, an aluminium honeycomb screen is spaced from that, with a screen-vacuum thermal insulation covering, and glass cloth over the top. It is about 50% less likely to be punctured, and crew move to the ROS when the station is under threat. Punctures on the ROS would be contained within the panels which are 70 cm square. Example of: A NASA model showing areas at high risk from impact for the International Space Station. Space debris is tracked remotely from the ground, and the station crew can be notified.

This allows for a (DAM) to be conducted, which uses thrusters on the Russian Orbital Segment to alter the station's orbital altitude, avoiding the debris. DAMs are not uncommon, taking place if computational models show the debris will approach within a certain threat distance. Eight DAMs had been performed prior to March 2009, the first seven between October 1999 and May 2003. Usually, the orbit is raised by one or two kilometres by means of an increase in orbital velocity of the order of 1 m/s. Unusually, there was a lowering of 1.7 km on 27 August 2008, the first such lowering for 8 years. There were two DAMs in 2009, on 22 March and 17 July.

If a threat from orbital debris is identified too late for a DAM to be safely conducted, the station crew close all the hatches aboard the station and retreat into their, so that they would be able to evacuate in the event the station was seriously damaged by the debris. This partial station evacuation has occurred on 13 March 2009, 28 June 2011, 24 March 2012 and 16 June 2015. End of mission. Many ISS resupply spacecraft have already undergone, such as According to a 2009 report, is considering methods to remove from the station some modules of the Russian Orbital Segment when the end of mission is reached and use them as a basis for a new station, called the (OPSEK). The modules under consideration for removal from the current ISS include the (Nauka), currently scheduled to be launched in mid-2018, and other Russian modules which are planned to be attached to Nauka afterwards.

Those modules would be within their useful lives in 2016 or 2020. The report presents a statement from an unnamed Russian engineer that, based on the experience from Mir, a 30-year life should be possible, except for micrometeorite damage, because the Russian modules have been built with on-orbit refurbishment in mind. According to the the United States and Russia are legally responsible for all modules they have launched. In ISS planning, NASA examined options including returning the station to Earth via shuttle missions (deemed too expensive, as the USOS is not designed for disassembly and this would require at least 27 shuttle missions ), natural orbital decay with random reentry similar to, boosting the station to a higher altitude (which would delay reentry) and a controlled targeted de-orbit to a remote ocean area. A controlled deorbit into a remote ocean was found to be technically feasible only with Russia's assistance. The Russian Space Agency has experience from de-orbiting the,,, and space stations; NASA's first intentional controlled de-orbit of a satellite (the ) occurred in 2000.

As of late 2010, the preferred plan is to use a slightly modified Progress spacecraft to de-orbit the ISS. This plan was seen as the simplest, cheapest and with the highest margin., the only space station built and launched entirely by the US, decayed from orbit slowly over 5 years, and no attempt was made to de-orbit it using a. Remains of Skylab hit populated areas of without injuries or loss of life.

The, a discussion by NASA and Boeing at the end of 2011, suggested using leftover USOS hardware and ' 2' [ ] as a refuelling depot and service station located at one of the Earth-Moon, L1 or L2. The entire USOS cannot be reused and will be discarded, but some Russian modules are planned to be reused., the, two science power platforms and Rassvet, launched between 2010 and 2015 and joined to the ROS, may be separated to form. Nauka will be used in the station, whose main goal is supporting manned deep space exploration. OPSEK will orbit at a higher inclination of 71 degrees, allowing observation to and from all of the Russian Federation. In February 2015, Roscosmos announced that it would remain a part of the ISS programme until 2024.

Nine months earlier—in response to US sanctions against Russia over the —Russian Deputy Prime Minister had stated that Russia would reject a US request to prolong the orbiting station's use beyond 2020, and would only supply rocket engines to the US for non-military satellite launches. A proposed modification that would reuse some of the ISS American and European segments is to attach a drive module to the vacated Node with its own onboard power source.

This would allow long-term reliability testing of the concept for less cost than building a dedicated space station from scratch. On 28 March 2015, Russian sources announced that Roscosmos and NASA had agreed to collaborate on the development of a replacement for the current ISS., the head of Russia's Roscosmos, made the announcement with NASA administrator Charles Bolden at his side. Komarov said 'Roscosmos together with NASA will work on the programme of a future orbital station', 'We agreed that the group of countries taking part in the ISS project will work on the future project of a new orbital station', 'The first step is that the ISS will operate until 2024', and that Roscosmos and NASA 'do not rule out that the station's flight could be extended'.

In a statement provided to SpaceNews on 28 March, NASA spokesman David Weaver said the agency appreciated the Russian commitment to extending the ISS, but did not confirm any plans for a future space station. On 30 September 2015, Boeing's contract with NASA as prime contractor for the ISS was extended to 30 September 2020.

Part of Boeing's services under the contract will relate to extending the station's primary structural hardware past 2020 to the end of 2028. Regarding extending the ISS, on 15 November 2016 General Director Vladimir Solntsev of RSC Energia stated 'Maybe the ISS will receive continued resources. Today we discussed the possibility of using the station until 2028,' and 'Much will depend on the political moments in relations with the Americans, with the new administration. It will be discussed.' Cost The ISS has been described as the most expensive single item ever constructed. In 2010 the cost was expected to be $150 billion. This includes NASA's budget of $58.7 billion (inflation-unadjusted) for the station from 1985 to 2015 ($72.4 billion in 2010 dollars), Russia's $12 billion, Europe's $5 billion, Japan's $5 billion, Canada's $2 billion, and the cost of 36 shuttle flights to build the station; estimated at $1.4 billion each, or $50.4 billion in total.

Assuming 20,000 person-days of use from 2000 to 2015 by two- to six-person crews, each person-day would cost $7.5 million, less than half the inflation-adjusted $19.6 million ($5.5 million before inflation) per person-day of Skylab. International co-operation. Naked eye The ISS is visible to the as a slow-moving, bright white dot because of reflected sunlight, and can be seen in the hours after sunset and before sunrise, when the station remains sunlit but the ground and sky are dark. The ISS takes about 10 minutes to pass from one horizon to another, and will only be visible part of that time because of moving into or out of the. Because of the size of its reflective surface area, the ISS is the brightest artificial object in the sky, excluding, with an approximate maximum of −4 when overhead (similar to Venus).

The ISS, like many satellites including the, can also produce flares of up to 8 or 16 times the brightness of as sunlight glints off reflective surfaces. The ISS is also visible during broad daylight conditions, albeit with a great deal more effort. Tools are provided by a number of websites such as (see below) as well as applications that use and the observer's longitude and latitude to indicate when the ISS will be visible (weather permitting), where the station will appear to rise, the altitude above the horizon it will reach and the duration of the pass before the station disappears either by setting below the horizon or entering into Earth's shadow.

In November 2012 NASA launched its 'Spot the Station' service, which sends people text and email alerts when the station is due to fly above their town. The station is visible from 95% of the inhabited land on Earth, but is not visible from extreme northern or southern latitudes. The as it the sun during an (4 frame composite image) Using a telescope-mounted camera to photograph the station is a popular hobby for astronomers, whilst using a mounted camera to photograph the Earth and stars is a popular hobby for crew. The use of a telescope or binoculars allows viewing of the ISS during daylight hours. Some amateur astronomers also use telescopic lenses to photograph the ISS while it the sun, sometimes doing so during an (and so the Sun, Moon, and ISS are all positioned approximatelly in a single line).

One example is during the, where at one location in Wyoming, images of the ISS were captured during the eclipse. Similar images were captured by NASA from a location in Washington. Parisian engineer and astrophotographer Thierry Legault, known for his photos of spaceships transiting the Sun, travelled to Oman in 2011 to photograph the Sun, Moon and space station all lined up. Legault, who received the Marius Jacquemetton award from the in 1999, and other hobbyists, use websites that predict when the ISS will transit the Sun or Moon and from what location those passes will be visible.