Hubble Space Telescope by the time it was due to be observed. Engineering support for HST is provided by NASA and contractor personnel at the Goddard Space Flight Center in Greenbelt, Maryland, south of the STScI. Hubble's operation is monitored 24 hours per day by four teams of flight controllers who make up Hubble's Flight Operations Team. By early 1986, the planned launch date of October that year looked feasible, but the "Challenger" accident brought the U.S. space program to a halt, grounding the Space Shuttle fleet and forcing the launch of Hubble to be postponed for several years. The telescope had to
Spitzer Space Telescope obscuring effects of Earth's atmosphere. In 1979, a report from the National Research Council of the National Academy of Sciences, "A Strategy for Space Astronomy and Astrophysics for the 1980s", identified a Space Infrared Telescope Facility (SIRTF) as "one of two major astrophysics facilities [to be developed] for Spacelab", a Shuttle-borne platform. Anticipating the major results from an upcoming Explorer satellite and from the Shuttle mission, the report also favored the "study and development of ... long-duration spaceflights of infrared telescopes cooled to cryogenic temperatures." The launch in January 1983 of the Infrared Astronomical Satellite, jointly developed by the United