The International Space Station (ISS) is a habitable, artificial satellite in low Earth orbit. The ISS follows the Salyut, Almaz, Cosmos, Skylab, and Mir space stations, as the 11th space station launched, not including the Genesis I and II prototypes. The ISS serves as a research laboratory that has a microgravity environment in which crews conduct experiments in many fields including biology, human biology, physics, astronomy and meteorology.[7][8][9] The station has a unique environment for the testing of the spacecraft systems that will be required for missions to the Moon and Mars.[10] The station is expected to remain in operation until at least 2020, and potentially to 2028.[11][12] Russia's next planned space station OPSEK, is to be separated prior to the ISS's deorbit to form a new, separate space station, intended to support deep space exploration.[13] Like many artificial satellites, the ISS can be seen from Earth with the naked eye.[14][15] The ISS is operated by Expedition crews, and has been continuously staffed since 2 November 2000—an uninterrupted human presence in space for the past 10 years and 351 days.[16] As of September 2011, the crew of Expedition 29 is aboard.
The ISS combines the Japanese Kibō laboratory with three space station projects, the Soviet/Russian Mir-2, the American Freedom, and the European Columbus.[18] Budget constraints led to the merger of these projects into a single multi-national programme. The station consists of pressurised modules, external trusses, solar arrays and other components which have been launched by Russian Proton rockets, American space shuttles, and Russian Soyuz rockets.[18] The station is maintained in orbit between 278 km (173 mi) and 460 km (286 mi) altitude, and travels at an average ground speed of 27,724 km (17,227 mi) per hour, completing 15.7 orbits per day.[19]
The ISS is a joint project between the five participating space agencies, the American NASA, the Russian RKA, the Japan Aerospace Exploration Agency JAXA, the European ESA, and the Canadian CSA.[20][21] The ownership and use of the space station is established in intergovernmental treaties and agreements[22] which divide the station into two areas and allow the Russian Federation to retain full ownership of Russian Orbital Segment (ROS)/(RS),[23] with the US Orbital Segment (USOS) allocated between the other international partners.[22] The station is serviced by Soyuz spacecraft, Progress spacecraft, the Automated Transfer Vehicle and the H-II Transfer Vehicle,[21] and has been visited by astronauts and cosmonauts from 15 different nations
Expedition 29 Launch 1998–2012 Launch pad Baikonur LC-81/23, LC-1/5
KSC LC-39,
Mass approximately 450,000 kg (990,000 lb) Length 51 m (167.3 ft)[citation needed]
from PMA-2 to Zvezda Width 109 m (357.5 ft)[citation needed]
along truss, arrays extended Height c. 20 m (c. 66 ft)
nadir–zenith, arrays forward–aft
(27 November 2009)[dated info] Pressurised volume 837 m3 (29,600 cu ft)
(21 March 2011) Atmospheric pressure 101.3 kPa (29.91 inHg, 1 atm) Perigee 376 km AMSL
(1 Oct 2011) Apogee 398 km AMSL
(1 Oct 2011) Orbital inclination 51.6 degrees Average speed 7,706.6 m/s
(27,743.8 km/h, 17,239.2 mph) Orbital period 91 minutes Days in orbit 4716
(19 October) Days occupied 4003
(19 October) Number of orbits 74025
From: Official International Space Statio
