Space Shuttle Columbia facility beginning in January 1984, undergoing modifications that removed the Orbiter Flight Test hardware and bringing it up to similar specifications as those of its sister orbiters. At that time the shuttle fleet was expanded to include "Discovery" and "Atlantis". "Columbia" returned to space on January 12, 1986, with the launch of STS-61-C. The mission's crew included Dr. Franklin Chang-Diaz, as well as the first sitting member of the House of Representatives to venture into space, Bill Nelson. The next shuttle mission, STS-51-L, was undertaken by "Challenger". It was launched on January 28, 1986, ten days after STS-61-C had landed,
Space Shuttle Pathfinder cost of US$1 million and hired Teledyne Brown Engineering to refurbish it to more closely resemble an actual Space Shuttle. It was named "Pathfinder" and displayed at the Great Space Shuttle Exposition in Tokyo from June 1983 to August 1984. After the exhibit, "Pathfinder" returned to the United States. The U.S. Space & Rocket Center in Huntsville, Alabama designed the display and built a stand. NASA provided MPTA-ET and two filament-wound Solid Rocket Booster casings, which had been designed for polar-orbit launches from Vandenberg Air Force Base. On February 16, 1988, NASA shipped MPTA-ET, a external tank, which had been