Space Shuttle gliding and landing; it was originally intended to be outfitted for orbital operations after the test program, but it was found more economical to upgrade the structural test article STA-099 into orbiter "Challenger" (OV-099). An additional test article, dubbed "Pathfinder" (OV-098), was built for form and fit tests, and is on display at the Alabama Space and Rocket Center in Huntsville, AL. "Challenger" disintegrated 73 seconds after launch in 1986, and "Endeavour" was built as a replacement from structural spare components. Building "Endeavour" cost about US$1.7 billion. "Columbia" broke apart over Texas during re-entry in 2003. A Space Shuttle launch
Space Shuttle program contractor for the program was North American Rockwell (later Rockwell International, now Boeing), the same company responsible for building the Apollo Command/Service Module. The contractor for the Space Shuttle Solid Rocket Boosters was Morton Thiokol (now part of Northrop Grumman Innovation Systems), for the external tank, Martin Marietta (now Lockheed Martin), and for the Space Shuttle main engines, Rocketdyne (now Aerojet Rocketdyne). The first orbiter was originally planned to be named "Constitution", but a massive write-in campaign from fans of the "Star Trek" television series convinced the White House to change the name to "Enterprise". Amid great fanfare, "Enterprise" (designated