International Space Station program out of 28 flights have not been to the ISS, and only the planned Hubble Space Telescope servicing mission in 2009 will not be ISS-related out of 13 planned missions until the end of the Space Shuttle program in 2010). The Space Shuttle was retired from service upon the conclusion of Atlantis' final flight on July 21, 2011. NASA was reliant even at the time on some of the resupply contracts being fielded out to Soyuz and Progress and the other unmanned tugs, but it had launched a few years earlier into a program of aggressive development of commercial US
Spitzer Space Telescope into a more extended mode of operation, possibly in association with a future space platform or space station. SIRTF would be a 1-meter class, cryogenically cooled, multi-user facility consisting of a telescope and associated focal plane instruments. It would be launched on the Space Shuttle and remain attached to the Shuttle as a Spacelab payload during astronomical observations, after which it would be returned to Earth for refurbishment prior to re-flight. The first flight was expected to occur about 1990, with the succeeding flights anticipated beginning approximately one year later. However, the Spacelab-2 flight aboard STS-51-F showed that the Shuttle