SPACE SHUTTLE

This video shows a takeoff and landing of a manned U.S. space shuttle. The shuttle's main reusable rocket-launched vehicle designed to go into Earth orbit, to transport people and cargo between Earth and orbiting spacecraft, and to glide to a landing on Earth. The first such vehicle, formally called the Space Transportation System (STS), was developed by the National Aeronautics and Space Administration (NASA) of the United States. The shuttle was first launched on April 12, 1981. The STS consists of three major components: (1) a winged orbiter that carries both crew and cargo; (2) an external tank containing liquid hydrogen (fuel) and liquid oxygen (oxidizer) for the orbiter's three main rocket engines; and (3) a pair of large, solid-propellant, strap-on booster rockets. At lift-off, the entire system weighs 4,400,000 pounds (2,000,000 kilograms) and stands 184 feet (56 metres) high. During launch the boosters and the orbiter's main engines fire together, producing 7,000,000 pounds (31,000,000 newtons) of thrust. The boosters are jettisoned about two minutes after lift-off and are parachuted to Earth for retrieval and eventual reuse. After the orbiter has exhausted the propellants in the external tank upon attaining 99 percent orbital velocity, it releases the structure, which disintegrates while falling through the atmosphere. Although it is launched vertically like conventional manned spacecraft (for example, Apollo or Soyuz), the orbiter differs from the latter in that it glides to a runway landing in the manner of an ordinary jet airplane. The orbiter is designed to reduce the high cost of space flights, and it can be reused as many as 100 times. The STS can transport applications satellites and probes in the orbiter cargo bay for deployment in space. It also can carry astronauts out to inoperative orbiting satellites in order to retrieve or repair them. Moreover, the shuttle orbiter serves as an orbiting space laboratory; on certain missions, it carries a special research facility called Spacelab in which a variety of scientific experiments can be performed. See also space exploration. By the mid-1980s four shuttle orbiters had seen serviceColumbia, Challenger, Discovery, and Atlantis. In 1986 the Challenger, with seven astronauts aboard, exploded shortly after lift-off. In 1991 the shuttle Endeavour was put into service.