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The Space Shuttle has been the primary U.S. spacecraft for manned missions since 1981. Five shuttles have been built, with 118 successful missions and two failures. It was the first reusable launch vehicle, but failed to lower the cost of spaceflight. The shuttle will be phased out in 2010 and replaced by the Orion vehicle.
The Space Shuttle, officially called the Space Transportation System, or STS, has been the primary U.S. spacecraft used for manned missions since 1981. Five Space Shuttles have been built at a total cost of approximately $2.2 billion USD: Columbia, Challenger, Discovery, Atlantis, and Strive. An additional Shuttle, the Enterprise, was not fit for space and built only for test purposes.
As of December 2007, there have been 118 successful shuttle missions and two failures. The two failures, of Challenger in 1986 and Columbia in 2003, were due respectively to catastrophic rocket failure and rupture during re-entry. On both occasions, all seven astronauts on board were killed.
The Space Shuttle has had an illustrious history as the first reusable launch vehicle. The concept of a reusable launch vehicle was initially introduced as a way to lower the cost of spaceflight, though it failed in this regard, being instead the most expensive project in NASA history. Notable Space Shuttle payloads include the Hubble Space Telescope, the Galileo spacecraft (which went on to study the moons of Jupiter), the Magellan spacecraft, the Chandra X-ray Observatory, and components of the International Space Station, the largest space project in history.
The Space Shuttle is powered by three different means: two solid-propellant rockets, a large external tank fueled by liquid oxygen and hydrogen at cryogenic temperatures, and an orbital maneuvering system. The two solid rocket boosters lift the Space Shuttle off the pad and eject from the orbiter two minutes after launch. Boosters descend by parachute for subsequent recovery.
The specifications of the orbiter are as follows:
• Length: 122.17 feet (37.24 m)
• Wingspan: 78.06 feet (23.79 m)
• Height: 58.58 feet (17.86 m)
• Curb weight: 151.205 lbs (68.585 kg)
• Gross Takeoff Weight: 240,000 lbs (109,000 kg)
• Maximum Landing Weight: 230,000 lbs (104,000 kg)
• Maximum Payload: 55,250 lbs (25,061 kg)
• Payload bay dimensions: 15 ft × 60 ft (4.6 m × 18.3 m)
• Operating altitude: 100 to 520 nautical miles (185 to 960 km)
• Speed: 25.404 ft/s (7.743 m/s, 27.875 km/h, 17.321 mi/h)
The Space Shuttle will be phased out in 2010, to be replaced by the Orion vehicle, designed to carry crews to the Moon and beyond.
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