It is one thing making wonders of engineering on earth and a whole different ballgame when you need to do it outside the planet in outer space. The International Space Station (ISS) is a research facility that is a joint project among the space agencies of the United States (NASA), Russia (RKA), Japan (JAXA), Canada (CSA) and eleven European countries. When completed in 2010, it will be the largest and grandest human endeavor away from home, and to build such a massive structure in such dangerous conditions is one magnificent tribute to both human will and skill.
The International Space Station (ISS) is a habitable artificial satellite in low Earth orbit. It follows the Salyut, Almaz, Skylab and Mir stations as the ninth space station to be inhabited. The ISS is a modular structure whose first component was launched in 1998. Like many artificial satellites, the station can be seen from Earth without any equipment (referred to as naked eye).] The ISS consists of pressurised modules, external trusses, solar arrays and other components. ISS components have been launched by American Space Shuttles as well as Russian Proton and Soyuz rockets. Budget constraints led to the merger of three space station projects with the Japanese Kibō module and Canadian robotics. In 1993 the partially built Soviet/Russian Mir-2, the proposed American Freedom, and the proposed European Columbus merged into a single multinational programme. The Russian Federal Space Agency (RSA/RKA) is using the ISS as a work site to assemble their next space station, called OPSEK. Modules and components for the new station began arriving on orbit in 2010, and the RSA plans to commission the new station before the remainder of the ISS is de-orbited.
The ISS serves as a microgravity and space environment research laboratory in which crew members conduct experiments in biology, human biology, physics, astronomy, meteorology and other fields. The station is suited for the testing of spacecraft systems and equipment required for missions to the Moon and Mars.
The station has been continuously occupied for 11 years and 286 days having exceeded the previous record of almost 10 years (or 3,644 days) held by Mir, in 2010. The station is serviced by Soyuz spacecraft, Progress spacecraft, the Automated Transfer Vehicle, the H-II Transfer Vehicle, and formerly the Space Shuttle. It has been visited by astronauts and cosmonauts from 15 different nations. On 25 May 2012, Space Exploration Technologies Corporation (or SpaceX) became the world's first privately held company to send a cargo load, the Dragon spacecraft, to the International Space Station.
The ISS programme is a joint project between five participating space agencies, the American NASA, the Russian Federal Space Agency, the Japanese JAXA, the European ESA, and the Canadian CSA.The ownership and use of the space station is established by intergovernmental treaties and agreements. The station is divided into two sections, the Russian orbital segment (ROS) and the United States orbital segment (USOS), which is shared by many nations. The ISS is maintained at an orbital altitude of between 330 km (205 mi) and 410 km (255 mi). It completes 15.7 orbits per day. The ISS is funded until 2020, and may operate until 2028.
Purpose
According to the original Memorandum of Understanding between NASA and RSA, the International Space Station was intended to be a laboratory, observatory and factory in space. 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
The ISS provides a platform to conduct scientific research that cannot be performed in any other way. While small unmanned spacecraft can provide platforms for zero gravity and exposure to space, 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. Kibō is intended to accelerate Japan's progress in science and technology, gain new knowledge and apply it to such fields as industry and medicine.
Expedition 8 Commander and Science Officer Michael Foale conducts an inspection of the Microgravity Science Glovebox
In order to detect dark matter and answer other fundamental questions about our universe, engineers and scientists from all over the world built the Alpha Magnetic Spectrometer (AMS), which NASA compares to the Hubble telescope, and says could not be accommodated on a free flying satellite platform due in part to its power requirements and data bandwidth needs. The Station simplifies individual experiments by eliminating the need for separate rocket launches and research staff. The primary fields of research include Astrobiology, astronomy, human research including space medicine and life sciences, physical sciences, materials science, Space weather and weather on Earth (meteorology). Scientists on Earth have access to the crew's data and can modify experiments or launch new ones; benefits generally unavailable on unmanned spacecraft. Crews fly expeditions of several months duration, providing approximately 160 man-hours a week of labour with a crew of 6.
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 solar wind, in addition to cosmic rays), high vacuum, extreme temperatures, and microgravity. Some simple forms of life called Extremophiles, including small invertebrates called Tardigrades can survive in this environment in an extremely dry state called Desiccation.
Comet Lovejoy photographed by Expedition 30 commander Dan Burbank
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 lengthy human spaceflight and space colonisation 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 travel to Mars. 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. 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.
Microgravity
Gravity is the most significant force acting upon the ISS, which is in constant freefall. This state of freefall, or perceived weightlessness, is not perfect however, being disturbed by four separate effects: One, the drag resulting 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 orbital decay. Two, vibration caused by mechanical systems and the crew (FARQ) on board the ISS. Three, orbital corrections by the on-board gyroscopes or thrusters. Four, the spatial separation from the real centre of mass of the ISS. Any part of the ISS not at the exact center of mass will tend to follow its own orbit. That is, parts on the underside, closer to the Earth are pulled harder, towards the Earth. Conversely, parts on the top of the station, farther from Earth, try to fling off into space. However, as each point is physically part of the station, this is impossible, and so each component is subject to small forces which keep them attached to the station as it orbits. This is also called the tidal force.
A comparison between the combustion of a candle on Earth (left) and in a microgravity environment, such as that found on the ISS (right).
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 microgravity's effects on the growth of three-dimensional, human-like tissues, and the unusual protein crystals that can be formed in space.
The investigation of the physics of fluids in microgravity will allow researchers to model the behaviour of fluids better. Because fluids can be almost completely combined in microgravity, physicists investigate fluids that do not mix well on Earth. In addition, an examination of reactions that are slowed by low gravity and temperatures will give scientists a deeper understanding of superconductivity.
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 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 aerosols, ozone, water vapour, and oxides in Earth's atmosphere, as well as cosmic rays, cosmic dust, antimatter, and dark matter in the universe.
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 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 Mars500 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 Mars500 may be carried out on the ISS.
A 3D plan of the Mars500 complex, used for ground-based experiments which complement ISS-based preparations for a manned mission to Mars
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." A manned mission to Mars, however, may be a multinational effort involving space agencies and countries outside of the current ISS partnership. In 2010 ESA Director-General Jean-Jacques Dordain stated his agency was ready to propose to the other 4 partners that China, India and South Korea be invited to join the ISS partnership. NASA chief Charlie Bolden stated in Feb 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
The ISS crew provide 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."[52] 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.
Susan J. Helms, Expedition Two flight engineer, talks to amateur radio operators on Earth from the Amateur radio workstation in the Zarya
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."
Amateur Radio on the ISS (ARISS) is a volunteer programme which 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 9 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.
A student speaks to crew using Amateur Radio, provided free by ARISS.
First Orbit is a feature-length documentary film about Vostok 1, 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 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, during Expedition 26/27, filmed the majority of the footage for this documentary film, and as a result is credited as its director of photography. The film was streamed through the website www.firstorbit.org in a global YouTube premiere in 2011, under a free license.
Origins
The International Space Station programme represents a combination of three national space station projects, the Russian/Soviet Mir-2, NASA's Freedom including the Japanese Kibō laboratory, and the European Columbus space stations. Canadian robotics supplement these projects. Mir-2 was originally authorised in the February 1976 resolution setting forth plans for development of third generation Soviet space systems and the first module, which would have served the same function as Zarya, was destroyed after launch. In the early 1980s, NASA planned to launch a modular space station called Freedom as a counterpart to the Soviet Salyut and Mir space stations. Freedom was never constructed and the remnants of the project became part of the ISS. 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 Rome in early 1985, science ministers from the European Space Agency (ESA) countries approved the Columbus program, the most ambitious effort in space undertaken by that organisation 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. The space station was also going to tie the emerging European and Japanese national space programmes closer to the U.S.-led project, thereby preventing those nations from becoming major, independent competitors too.[59] In September 1993, American Vice-President Al Gore, Jr., and Russian Prime Minister Viktor Chernomyrdin announced plans for a new space station, which eventually became the International Space Station.[60] They also agreed, in preparation for this new project, that the United States would be involved in the Mir programme, including American Shuttles docking, in the Shuttle-Mir Program.
Mir-2
The Russian Orbital Segment (ROS or RS) is the eleventh Soviet-Russian space station. Mir ("Peace") and the ISS are successors to the Salyut ("Fireworks") and Almaz ("Diamond") stations. The first MIR-2 module was launched in 1986 by an Energia heavy-lift expendable launch system. The launcher worked properly, however the Polyus payload fired its engines to insert itself into orbit whilst in the wrong position due to a programming error, and re-entered the atmosphere. The planned station changed several times, but Zvezda was always the service module, containing the stations critical systems such as life support. The station would have used the Buran spaceplane and Proton rockets to lift new modules into orbit. The spaceframe of Zvezda, also called DOS-8 serial number 128, was completed in February 1985 and major internal equipment was installed by October 1986.
The Soviet Buran shuttle would have carried modules up to 30 tons to MIR-2. 80–100 ton modules could have used its launcher without the shuttle
The Polyus module or spacecraft would have served as the FGB, a foundation which provides propulsion and guidance, but lacks life support. Polyus was a satellite interceptor/destroyer, carrying a 1 MegaWatt carbon dioxide laser. The module had a length of almost 37 m and a diameter of 4.1 m weighed nearly 80 t and included 2 principal sections, the smallest, the functional service block (FGB) and the largest, the aim module.
In 1983, the design was changed and the station would consist of Zvezda, followed by several 90 metric ton modules and a truss structure similar to the current station. The draft was approved by NPO Energia Chief Semenov on 14 December 1987 and announced to the press as 'Mir-2' in January 1988. This station would be visited by the Soviet Buran, but mainly resupplied by Progress-M2 spacecraft. Orbital assembly of the station was expected to begin in 1993. In 1993 with the collapse of the Soviet Union, a redesigned smaller Mir-2 was to be built whilst attached to Mir, just as OPSEK is being assembled whilst attached to the ISS.
Freedom with Kibō
Approved by then-president Ronald Reagan and announced in the 1984 State of the Union Address, "We can follow our dreams to distant stars, living and working in space for peaceful economic and scientific gain", the proposed Freedom changed considerably.
NASA's first cost assessment in 1987 revealed the 'Dual Keel' Station would cost $14.5 billion. This caused a political uproar in Congress, and NASA and Reagan Administration officials reached a compromise in March 1987 which allowed the agency to proceed with a cheaper $12.2-billion Phase One Station that could be completed after 10 or 11 Shuttle assembly flights. This design initially omitted the $3.4-billion 'Dual Keel' structure and half of the power generators. The new Space Station configuration was named 'Freedom' by Reagan in June 1988. Originally, Freedom would have carried two 37.5 kW solar arrays. However, Congress quickly insisted on adding two more arrays for scientific users. The Space Station programme was plagued by conflicts during the entire 1984–87 definition phase. In 1987, the Department of Defense (DoD) briefly demanded to have full access to the Station for military research, despite strong objections from NASA and the international partners. Besides the expected furore from the international partners, the DoD position sparked a shouting match between Defense Secretary Caspar Weinberger and powerful members of Congress that extended right up to the final Fiscal 1988 budget authorisation in July 1987. Reagan wanted to invite other NATO countries to participate in the U.S-led project, since the Soviet Union had been launching international crews to their Salyut space stations since 1971. At one point, then-anonymous disgruntled NASA employees calling themselves "Center for Strategic Space Studies" suggested that instead of building Freedom, NASA should take the back-up Skylab from display in the National Air and Space Museum in Washington and launch that.
Artist's conception of the proposed "Power Tower" space station with the Japanese Experiment Module attached
An agreement signed in September 1988 allocated 97% of the US lab resources to NASA while the Canadian CSA would receive 3% in return for its contribution to the programme. Europe and Japan would retain 51% of their own laboratory modules. Six Americans and two international astronauts would be permanently based on Space Station Freedom. Several NASA Space Shuttle missions in the 1980s and early 1990s included spacewalks to demonstrate and test space station construction techniques.
The Japanese Experiment Module (JEM), christened Kibō ("hope") in 1999, is Japan's first manned spacecraft. Kibō consists of a pressurised laboratory dedicated to advanced technology experiments, education and art, a cargo bay, an unpressurised pallet for vacuum experiments in space, a robotic arm, and interorbital communication system. While the proposed space station was redesigned many times around Kibō, the only significant change has been the placement of its ballistic shielding. Its final position at the front of the station increases the risk of damage from debris. The ESA and NASA, by contrast, both reduced the size of their laboratories over the course of the program. The Japanese National Space Development Agency (NASDA) formally submitted the JEM proposal to NASA in March 1986, and by 1990 design work began. Constructed in the Tobishima Plant of Nagoya Aerospace Systems Works, by Mitsubishi Heavy Industries, Ltd., Kibō made its way to the Tsukuba Space Center and in 2003 Kibō was shipped, first by river barge and then by ship, to America. In 2010, Kibō won the Good Design Award, a 55 year old consumer and industry award which identifies the best of Japanese craftsmanship.
A decade before Zarya was launched into orbit, Japan was working on the development of its own space shuttle, intended to use the H-II launcher. Depending on the configuration of the launcher, it would weigh between 10 and 20 metric tons and mix crew and cargo together. It would take off vertically on its booster and at the end of its mission re-enter and land just as the NASA and Soviet shuttles did. The program was terminated by JAXA in 2003 after scale mockup testing.
Columbus
The first elements of the Columbus program were expected to fly as early as 1992, to coincide with the 500th anniversary of Columbus' voyage to America. ESA and NASA clashed over the very concept of the Columbus program in 1986. America objected to ESA's using Columbus as building block of a future European space station, and were concerned that they would facilitate the creation of a potential competitor if the manned space outpost fulfilled its promise as supplier of commercially viable products, such as new materials and pharmaceuticals. Plans were scaled down as a result, and by 1988, Europe proposed to participate with three elements, the Columbus module, the Man-Tended Free Flyer (MTFF), and the Polar Platform (PPF), supported by the Ariane-5 launcher and the Hermes spaceplane.
The Columbus Man-Tended Free Flyer (MTFF) was an ESA programme to develop a space station that could be used for a variety of microgravity experiments while serving ESA's needs for an autonomous manned space platform.[74] The MTFF would be a space station without long term life support, visited by short term crews to replenish and maintain experiments in a Zero-G environment free of vibrations caused by a permanent crew. The project was canceled after budget constraints caused by German reunification. The Hermes spaceplane is comparable in function to the American and Soviet space shuttles, with a smaller crew of up to 6 (reduced to 3 with ejection seats after the Columbia disaster) and substantially smaller cargo capacity, 4,550 kg, comparable to ISS unmanned cargo ships.
By 1991 the Columbus and Hermes pre-development activities were good enough to progress into full development, however profound geopolitical changes prompted examining broader international cooperation, in particular with the Russian Federation. ESA Member States approved the complete development of the Attached Pressurised Module (APM) and the Polar Platform (PPF) for Columbus, but the Man-Tended Free-Flyer (MTFF) was abandoned. The Hermes programme was reoriented into the Manned Space Transportation Programme (MSTP), and a three-year period extending from 1993 to 1995 was agreed on in order to define a future manned space transportation system in cooperation with Russia, including joint development and use of Mir-2.
The ESA ATV robot spacecraft is a powerful 'space tug' that can be adapted to shuttle supplies into Mars orbit. Its propulsion is arranged with a central hollow section, to allow the possibility of a docking port at both ends. It could then form larger assemblies, strung together as a space station or allowing piggyback docking to Zvezda.
