Spacelab was not designed for independent orbital flight, but remained in the Shuttle's cargo bay as the astronauts entered and left it through an airlock. On June 18, 1983 Sally Ride became the first American woman in space, on board the Space Shuttle "Challenger" STS-7 mission. Another famous series of missions were the launch and later successful repair of the Hubble Space Telescope in 1990 and 1993, respectively. In 1995, Russian-American interaction resumed with the Shuttle–Mir missions (1995–1998). Once more an American vehicle docked with a Russian craft, this time a full-fledged space station. This cooperation has continued with Russia and the United States as two of the biggest partners in the largest space station built: the International Space Station (ISS). The strength of their cooperation on this project was even more evident when NASA began relying on Russian launch vehicles to service the ISS during the two-year grounding of the shuttle fleet following the 2003 Space Shuttle "Columbia" disaster. The Shuttle fleet lost two orbiters and 14 astronauts in two disasters: "Challenger" in 1986, and "Columbia" in 2003. While the 1986 loss was mitigated by building the Space Shuttle "Endeavour" from replacement parts, NASA did not build another orbiter to replace the second loss. NASA's Space Shuttle program had 135 missions when the program ended with the successful landing of the Space Shuttle "Atlantis" at the Kennedy Space Center on July 21, 2011. The program spanned 30 years with over 300 astronauts sent into space. The International Space Station (ISS) combines NASA's "Space Station Freedom" project with the Soviet/Russian "Mir-2" station, the European "Columbus" station, and the Japanese Kibō laboratory module. NASA originally planned in the 1980s to develop "Freedom" alone, but US budget constraints led to the merger of these projects into a single multi-national program in 1993, managed by NASA, the Russian Federal Space Agency (RKA), the Japan Aerospace Exploration Agency (JAXA), the European Space Agency (ESA), and the Canadian Space Agency (CSA). The station consists of pressurized modules, external trusses, solar arrays and other components, which were manufactured in various factories around the world, and have been launched by Russian Proton and Soyuz rockets, and the US Space Shuttles. It is currently being assembled in Low Earth Orbit. The on-orbit assembly began in 1998, the completion of the US Orbital Segment occurred in 2019 and the completion of the Russian Orbital Segment is expected by 2020s.