Space Shuttle orbiter its maiden flight in 1977. An unpowered glider, it was carried by a modified Boeing 747 airliner called the Shuttle Carrier Aircraft and released for a series of atmospheric test flights and landings. "Enterprise" was partially disassembled and retired after completion of critical testing. The remaining orbiters were fully operational spacecraft, and were launched vertically as part of the Space Shuttle stack. "Columbia" was the first space-worthy orbiter, and made its inaugural flight in 1981. "Challenger", "Discovery", and "Atlantis" followed in 1983, 1984 and 1985 respectively. In 1986, "Challenger" was destroyed in an accident shortly after launch. "Endeavour" was built
Space Shuttle Independence Space Center outside Houston, Texas. The replica shuttle was stripped of the name "Explorer" as part of the dismantling process. Upon arriving in the Houston area by barge on June 1, 2012, the shuttle was taken to the Johnson Space Center dock on Clear Lake, and preparations were made to move the shuttle to Space Center Houston during the early morning hours. As with Florida, several light poles along NASA Parkway were taken down and trees trimmed back to allow passage. The shuttle was moved by another 144-wheel trailer down the closed highway to the visitor center. Johnson Space Center