THE INTERNATIONAL SPACE STATION

INTERNATIONAL SPACE STATION (ISS)

The International Space Station (ISS) is a 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 around 2015.^[6] As of 2009^[update], the ISS is the largest artificial satellite in Earth orbit, larger than any previous space station.^[7]

The ISS programme 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).^[8][b] The Brazilian Space Agency (AEB) participates through a separate contract with NASA.^[9] 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).^[10] China has reportedly expressed interest in the project, especially if it would be able to work with the RKA, although as of 2009^[update] it is not involved.^[11][12]

The space station is in a Low Earth Orbit, and can be seen from Earth with the naked eye. It orbits at an altitude of approximately 350 kilometres (220 mi; 190 nmi) above the surface of the Earth,^[13][14][15] travelling at an average speed of 27,724 kilometres (17,227 mi) per hour, completing 15.7 orbits per day.^[13]

The ISS has been continuously staffed since the first resident crew, Expedition 1, entered the station on 2 November 2000. This has provided a permanent human presence in space for the last &0000000000000008.0000008 years, &0000000000000213.000000213 days.^[16] Prior to May 2009, the station had the capacity for a crew of three. However, to fulfil an active research programme, since the arrival of Expedition 20, it has been staffed by a resident crew of six. The crew of Expedition 20 is currently aboard.^[17][18]

Early crew members all came from the Russian and American space programmes until German ESA astronaut Thomas Reiter joined the Expedition 13 crew in July 2006, becoming the first crew member from another space agency. The station has been visited by astronauts from 16 different nations, and it was the destination of the first six space tourists.

The International Space Station serves primarily as a research laboratory and is the largest 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. Long-term expedition crews conduct science daily (approximately 160 man-hours a week),^[20] 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^[update], 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.

The ISS also provides a testing location for efficient, reliable spacecraft systems that will be required for long-duration missions to the Moon and Mars, allowing for equipment to be evaluated in the relatively safe location of Low Earth Orbit. This provides experience in maintaining, repairing, and replacing systems on-orbit, which will be essential in operating spacecraft further from Earth. This aspect of ISS operations reduces mission risks, and advances the capabilities of interplanetary spacecraft.

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.