Space Shuttle Columbia that remained fitted to the avionics suite, and an internal airlock that, originally fitted into the other orbiters, was later removed in favor of an external airlock to facilitate Shuttle/Mir and Shuttle/International Space Station dockings. Due to its weight, "Columbia" could not have used the planned Centaur-G booster (cancelled after the loss of "Challenger"). The retention of the internal airlock allowed NASA to use "Columbia" for the STS-109 Hubble Space Telescope servicing mission, along with the Spacehab double module used on STS-107. Due to "Columbia's" heavier weight, it was less ideal for NASA to use it for missions to the
Hopkins Ultraviolet Telescope on Astro-2 (in 1995). HUT is on display at the Smithsonian National Air and Space Museum in Washington, D.C. in the United States. Hopkins Ultraviolet Telescope The Hopkins Ultraviolet Telescope (HUT) was a space telescope designed to make spectroscopic observations in the far-ultraviolet region of the electromagnetic spectrum. It was flown into orbit on the Space Shuttle and operated from the Shuttle's payload bay on two occasions: in December 1990, as part of Shuttle mission STS-35, and in March 1995, as part of mission STS-67. HUT was designed and built by a team based at Johns Hopkins University, led by