Security ... think about it!
The ISS is a synthesis of several space station projects that includes the American Freedom, the Soviet/Russian Mir-2, the European Columbus and the Japanese KibÅ. Budget constraints led to the merger of these projects into a single multi-national programme. The ISS project began in 1994 with the Shuttle-Mir programme, and the first module of the station, Zarya, was launched in 1998 by Russia. Assembly continues, as pressurised modules, external trusses and other components are launched by American space shuttles, Russian Proton rockets and Russian Soyuz rockets. As of November 2009[update], the station consisted of 11 pressurised modules and an extensive integrated truss structure (ITS). Power is provided by 16 solar arrays mounted on the external truss, in addition to four smaller arrays on the Russian modules. The station is maintained at an orbit between 278 km (173 mi) and 460 km (286 mi) altitude, and travels at an average speed of 27,724 km (17,227 mi) per hour, completing 15.7 orbits per day.