Lyman Spitzer
The concept for a space-based telescope is credited to Lyman Spitzer when in 1946 he wrote a paper entitled: Astronomical Advantages of an Extra-Terrestrial Observatory. While teaching as Princeton University he was asked to head the National Academy of Science Ad Hoc Committee on Large Space Telescopes. This committee began the task of studying the feasibility of such an instrument. In 1969 they published their findings in a reports entitled Scientific Uses of the Large Space Telescope. NASA would embrace their findings becoming the lead agency in developing the project (Okolski, n.d.)
It was not until 1971 that NASA created a Large Space Telescope Science Steering Group to begin studying the feasibility of a three-meter diameter telescope with an estimated cost of $400 to $500 million. The large cost associated with the project which created difficulty in getting Congress to fund it. In 1975 the European Space Agency (ESA) became involved in the project and reduced the telescope to 2.4 meters which in turn reduced the cost to $200 million (Okolski, n.d.) .
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In 1977 Congress officially funded the project that had already completed the design stage. NASA awarded contracts to build the optical portion to Perkin-Elmer Corporation with Lockheed Missiles and Space to developing the telescopes' housing. Perkin-Elmer completed the telescopes' mirrors using computer-controlled lasers; however, a programming glitch would later be to blame for the blurred images that hampered HST from enjoying early success after its launch (O'Dell, 2008, p. 267).
Hubble's two mirrors were ground so that they do not deviate from a perfect curve by more than 1/800,000th of an inch. If Hubble's primary mirror were scaled up to the diameter of the Earth, the biggest bump would be only six inches tall. Image from: http://hubblesite.org/the_telescope/hubble_essentials/quick_facts.php
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Mirrors are at the heart of the Hubble's imaging capabilities. Here's a look at the primary mirror on the telescope, which is about 8 feet in diameter (2.4 meters) and weighs 1,820 pounds (826 kilograms). It's made of silica glass and coated with a thin layer of aluminum to reflect visible light. There's an even thinner layer of magnesium fluoride on top of that to reflect ultraviolet light and prevent oxidation ("Hubble Space Telescope Pictures", n.d.). See more pictures at the following web site: http://dsc.discovery.com/tv-shows/curiosity/topics/hubble-space-telescope-pictures.htm |
In 1992 NASA formed the Space Telescope Science Institute (STSI) which is a part of the Association of University for Research in Astronomy (AURA) who was tasked with the management of the telescopes' science programs. The spacecraft was named in 1983 after the famous astronomer Edwin P. Hubble ("A Chronology of the Hubble Space Telescope", n.d.).
Edwin Hubble Astronomer
Edwin Powell Hubble was an American astronomer who played a crucial role in establishing the field of extragalactic astronomy and is generally regarded as one of the most important observational cosmologists of the 20th century. Born: November 20, 1889, Marshfield, MO Died: September 28, 1953, San Marino, CA Spouse: Grace Burke (m. 1924) Awards: Legion of Merit, Franklin Medal, Gold Medal of the Royal Astronomical Society, Bruce Medal Education: University of Oxford, The Queen's College, Oxford, University of Chicago ("Edwin Hubble", n.d) |
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By 1984 the optical system portion of the project was complete with the final assembly of the spacecraft being completed by Lockheed in 1985. The first scheduled launch for Hubble was in 1986; however, it experienced several delays including the Challenger disaster. On April 24, 1994, Hubble was launched aboard Discovery on STS-31. It was later that scientists discovered the spherical aberration in the mirror that lead to the slightly blurred images (Okolski, n.d.) .
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A service mission to fix that problem was successfully undertaken in December, 1993. . Since that time, four additional service missions have been launched to further Hubble’s abilities to explore deeper into the universe and to prolong HST service life, all of which have been successfully completed. Because HST is the only one of the four Great Observation space platforms designed to be serviced by astronauts, it has allowed it to serve the scientific community far beyond its originally designed capabilities (Okolski, n.d.) .
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