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 Independence display cases with shuttle program artifacts. On August 14, 2014, a heavy lift was completed to place "Independence" on top of NASA 905, which had been moved to Space Center Houston from Ellington Field on April 30, 2014. The combined exhibit, named "Independence Plaza", opened to the public on January 23, 2016, at an estimated cost of . Space Shuttle Independence Space Shuttle "Independence, formerly known as Explorer", is a full-scale, high-fidelity replica of the Space Shuttle. It was built by Guard-Lee in Apopka, Florida, installed at Kennedy Space Center Visitor Complex in 1993, and moved to Space Center Houston