The Hubble Space Telescope is a cooperative program of the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA) for the operation of a long lived space based observatory for the benefit of the international astronomical community. The idea was first developed in the 1940s, designed and built in the 1970s and 80s, and made operational only in the 1990s. This was to be a different type of mission for NASA, to create a long term space based observatory. In order to accomplish this goal and to protect the spacecraft against instrument and equipment failures, NASA had always planned on regular servicing missions. The Hubble has special grapple fixtures, 76 handholds, and is stabilized in all three axes. The Hubble is a 2.4 meter reflecting telescope which was deployed in low Earth orbit at 600 kilometers by the crew of the space shuttle Discovery on 25 April 1990. Responsibility for conducting and coordinating the science operations of the Hubble Space Telescope rests with the Space Telescope Science Institute on the Johns Hopkins University Homewood Campus in Baltimore, Maryland, which in turn is operated for NASA by the Association of Universities for Research in Astronomy, Inc. ("General Overview of the Hubble Space Telescope," 1999). Since its deployment, the Hubble has returned thousands of phonographs and other data and has been instrumental in a number of important discoveries and in testing and confirming various theories.
The current complement of science instruments on the Hubble include three cameras, two spectrographs, and fine guidance sensors (primarily used for astrometric observations). Because of the Hubble's placement above the Earth's atmosphere, these science instruments can produce high resolution images of astronomical objects such as would be impossible through the atmosphere. Ground based telescopes can seldom provide resolution better than 1.0 arc seconds, while t...