International Space Station
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International Space Station(ISS) An internationally managed permanently crewed spacecraft providing an Earth-orbiting platform intended to function as an observatory, laboratory, manufacturing facility, assembly facility, and staging post. The ISS began as an ambitious program originated by the USA in 1984 under the name Freedom. The project went through several revisions of its design in order to reduce costs and meet Congressional budgetary limitations. Meanwhile Russia, with its considerable experience in building and running its Salyut and Mir space stations, was contemplating the development of a successor to Mir, Mir-2. Following the break-up of the Soviet Union in 1991, however, the Russians too faced budgetary restrictions. In September 1993 the USA and the Russian Federation signed an agreement to merge the Freedom and Mir-2 projects, resulting in the birth of the ISS. Since then, the project has been widened to embrace contributions from 16 countries in all: the USA, Russia, Japan, and Canada; the ESA member countries Italy, Belgium, the Netherlands, Denmark, Norway, France, Spain, Germany, Sweden, Switzerland, and the UK; and Brazil.
Assembly of the ISS in space began Nov. 20 1998, when the first module, Zarya (Sunrise), was carried into orbit by a Russian Proton rocket from the Baikonur Cosmodrome in Kazakhstan. Zarya was the first of several elements originally intended by the Russians for incorporation into Mir-2. It served as the power and propulsion unit of the ISS. In Dec. 1998 the US space shuttle Endeavour lifted the US-made Unity module into orbit and linked it to Zarya. With the fifth ISS assembly mission, which took place in July 2000, the Russian-made Zvezda (Star) module was installed, providing living accommodation for the crew and housing the station's control room.
There followed two more missions to install supplies and equipment, including batteries and communications facilities as well as the US-made Z1 Truss, which among other things served as a framework for the attachment of early US solar arrays. Then on Oct. 31 2000, in the eighth mission to the ISS, the three-member Expedition 1, consisting of US Commander William Shepherd, Russian Commander Yuri Gidzenko and Russian Flight Engineer Sergey Krikalyev, blasted off from Baikonur aboard a Russian Soyuz launch vehicle. On Nov. 2 2000 these astronauts boarded the ISS to commence humanity's ongoing residence in Earth orbit. Their stay lasted four months, at the end of which they handed over to the newly arrived Expedition 2.
Assembly and maintenance of the space station continues, with each country in the ISS team making an important contribution. For example, the US-made Destiny Laboratory was delivered Feb. 2001 to provide a comfortable environment for year-round research in many fields. Canada's robotic arm, Canadarm2, was delivered Apr. 2001 and was used to install the US-made airlock, Quest. The tragic loss of the space shuttle Columbia in 2003 meant that for more than two years US participation in the ISS had to rely on Russia for transportation to and from the station. ESA's main contribution to the ISS is the Columbus program, due for installation in 2006.
By the end of 2004, Expedition 10 had taken up residence aboard the ISS. Each crew had added greatly to the sum of human experience about living in space.