Shuttle

The US Space Shuttle is the centerpiece of America's launch capabilities.  The only launch vehicle that the US currently has which is capable of lifting people into space, the shuttle is launched from NASA's Kennedy Space Center at Cape Canaveral in Florida. In operation since April 12, 1981 there are 4 orbiters in the shuttle fleet.  These are Columbia, Atlantis, Discovery and Endeavour.  Endeavour was built to replace the Space Shuttle Challenger which was destroyed in an accident on January 28, 1986, killing all seven on board. This was the twenty-fifth launch.  Since the shuttle program restarted in 1988, a further fifty flights have been successful.

The space shuttle consists of three main parts.  These are the orbiter, the external tank and the solid rocket boosters.  The orbiter is the only part of the system that goes all the way into space and comes back again.  It carries the crew, the cargo and the Space Shuttle's main engines.  The external tank contains the liquid hydgrogen and liquid oxygen that the main engines burn.  It is the only part of the Space Shuttle which is not reused.  The external tank is jettisoned over the Indian Ocean where it reenters the atmosphere and burns up. The solid rocket boosters are attached to the external tank and provide the initial lift needed to get the shuttle off the launch pad and started on its way into orbit. After their fuel is spent, the boosters separate from the external tank and parachute into the Atlantic Ocean where they are recovered by ship, refurbished and reused.
