Marshall Space Flight Center previous Spacelab missions were operated. The advent of the Space Shuttle made possible several major space programs in which MSFC had significant responsibilities. These were the International Space Station, the Hubble Space Telescope, the Chandra X-Ray Observatory, and the Compton Gamma-Ray Observatory. The latter three are part of NASA's series of Great Observatories; this series also includes the Spitzer Space Telescope, but this was not launched by a Space Shuttle and MSFC had no significant role in its development. A manned space station had long been in the plans of visionaries. Wernhar von Braun, in his widely read "Collier's Magazine"
Space Shuttle program for frequent flights. Various shuttle concepts had been explored since the late 1960s. The program formally commenced in 1972, becoming the sole focus of NASA's manned operations after the Apollo, Skylab, and Apollo-Soyuz programs in 1975. The Shuttle was originally conceived of and presented to the public in 1972 as a 'Space Truck' which would, among other things, be used to build a United States space station in low Earth orbit during the 1980s and then be replaced by a new vehicle by the early 1990s. The stalled plans for a U.S. space station evolved into the International Space Station