INTERNATIONAL SPACE STATION:
The International Space Station (ISS) is an internationally developed research facility currently being assembled in Low Earth Orbit. On-orbit construction of the station began in 1998 and is scheduled to be complete by 2011, with operations continuing until at least 2015. The ISS orbits at an altitude of approximately 350 kilometres (220 mi) above the surface of the Earth, travelling at an average speed of 27,724 kilometres (17,227 mi) per hour, completing 15.7 orbits per day.The station can be seen from the Earth with the naked eye, and, as of 2009, is the largest artificial satellite in Earth orbit, with a mass larger than that of any previous space station.
The ISS is a joint project among the space agencies of the United States (National Aeronautics and Space Administration—NASA), Russia (Russian Federal Space Agency—RKA), Japan (Japan Aerospace Exploration Agency—JAXA), Canada (Canadian Space Agency—CSA) and ten European nations (European Space Agency—ESA).The Brazilian Space Agency (AEB) participates through a separate contract with NASA.The Italian Space Agency (ASI) similarly has separate contracts for various activities not done within the framework of ESA's ISS projects (where Italy also fully participates).China has reportedly expressed interest in the project, especially if it would be able to work with the RKA, although as of 2009 it is not involved due to objections from the United States.
The station consists of a number of pressurised modules and unpressurised components, which have been launched by Space Shuttle, Soyuz rocket or Proton rocket. The ISS is serviced by a wide variety of manned and unmanned spacecraft, including the Soyuz spacecraft, Progress spacecraft, Space Shuttle and Automated Transfer Vehicle, and has been visited by astronauts from 16 different nations. The various sections of the station are controlled by several mission control centres on the ground, including MCC-H, TsUP, Col-CC, ATV-CC, JEM-CC, HTV-CC and MSS-CC.
PURPOSE:
The International Space Station serves primarily as a research laboratory and is the largest satellite ever launched into orbit.The station offers an advantage over spacecraft such as NASA's Space Shuttle because it is a long-term platform in the space environment, allowing long-duration studies to be performed, both on specific experiments and on the human crews that operate them. The presence of a permanent crew also means that the station offers benefits over other unmanned spacecraft as experiments can be monitored, replenished, repaired or replaced as required by the crew, as can various other components of the spacecraft itself. This means that scientists on the ground have swift access to their data and can modify experiments or fly new ones as and when required, benefits generally unavailable on specialised unmanned spacecraft.
Crews flying long-term expeditions, lasting several months, conduct science daily (approximately 160 man-hours a week)across a wide variety of fields, including human research, life sciences, physical sciences, and Earth observation, as well as education and technology demonstrations.As of June 2006, 90 science investigations had been conducted on the ISS over 64 months of continuous research. In addition, there have been nine research racks and more than 7,700 kg (17,000 lb) of research equipment and facilities launched to the station. Scientific findings, in fields ranging from basic science to exploration research, are being published every month
Finally, in addition to the scientific and research aspects of the station, there are numerous opportunities for educational outreach and international cooperation. The crews of the ISS provide educational opportunities for students back home on Earth, including student-developed experiments, educational demonstrations, student participation in classroom versions of ISS experiments, NASA investigator experiments, and ISS engineering activities. The ISS programme itself, and the international cooperation that it represents, allows 14 nations to live and work together in space, providing important lessons that can be taken forward into future multi-national missions
SCIENTIFIC RESEARCH:
One of the main goals of the ISS is to provide a place to conduct experiments that require one or more of the unusual conditions present on the station. The main fields of research include biology, physics, astronomy, and meteorology.The 2005 NASA Authorization Act designated the US segment of the International Space Station as a national laboratory with a goal to increase the use of the ISS by other Federal entities and the private sector.
One research goal is to improve the understanding of long-term space exposure on the human body. Subjects currently under study include muscle atrophy, bone loss, and fluid shift. The data will be used to determine whether space colonisation and lengthy human spaceflight are feasible. As of 2009, 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 following a lengthy space cruise.
The effect of near-weightlessness on non-human subjects is being considered as well. Researchers are investigating the relation of the near-weightless environment of outer space to evolution, development and growth, and the 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.
Researchers are investigating the physics of fluids in microgravity, enabling them to better model the behaviour of fluids in the future. Due to the ability to almost completely combine fluids in microgravity, physicists are interested in investigating the combinations of fluids that will not normally mix well on Earth. In addition, by examining reactions that are slowed down by low gravity and temperatures, scientists hope to gain new insight regarding superconductivity
One component assisting in these various studies is the ExPRESS Logistics Carrier (ELC). Developed by NASA, four of these units are set to be launched to the ISS. As currently envisioned, the ELCs will be delivered on three separate Space Shuttle missions. They will allow experiments to be deployed and conducted in the vacuum of space, and will provide the necessary electricity and computing to process experimental data locally. Delivery is currently scheduled for STS-129 in November 2009, STS-133 in May 2010 and STS-134 in September 2010.
The Alpha Magnetic Spectrometer (AMS), a particle physics experiment, is also scheduled to be added to the station. This device will be launched on STS-134 in 2010, and will be mounted externally on the Integrated Truss Structure. The AMS will search for various types of unusual matter by measuring cosmic rays. The experiments conducted will help researchers study the formation of the universe, and search for evidence of dark matter and antimatter.
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