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The Hubble Space Telescope. The Background. Even though the telescope has only been in orbit since 1990, the idea of a “space-based optical observatory” actually came after WWII in 1946
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The Background • Even though the telescope has only been in orbit since 1990, the idea of a “space-based optical observatory” actually came after WWII in 1946 • Lyman Spitzer, a professor at Yale University, argued that a telescope placed in outer space would give significant advantages to any telescope on the ground. • He believed that it would help scientists so much, he wrote a paper on its advantages called “Astronomical Advantages of an Extra-Terrestrial Observatory”
Astronomical Advantages of an Extra-Terrestrial Observatory • Describes how the Earth’s atmosphere distorts the images that even the most high quality telescopes on earth can produce. • A telescope in orbit can avoid this phenomena • The earth’s atmosphere also blocks X-ray emissions from stars. • A telescope in outer space, out of the earth’s atmosphere, can better detect these emissions from stars, planets, and other phenomena
The Background • A meeting held in 1966, National Academy of Science Ad Hoc Committee on the Large Space Telescope headed by Spitzer conducted comprehensive studies determining the pros and cons of having a telescope in outer space • This would determine if it was worth funding • It would also have to prove to NASA that it was worth funding • NASA would be the only organization that would be able to make this concept a reality because of funding and construction
Background • Werhner Von Braun had looked into a space telescope • World’s leading rocket scientists who came from Germany after WWII • Believed it would be too challenging • NASA itself had also looked into the advantages of a space telescope • Their original plan for the telescope had mirrors that were smaller than the ones proposed by Spitzer and his group
Coming Together • In 1971, NASA’s acting administrator, George Low, gave the go ahead for a Large Space Telescope Science Steering Group to conduct studies determining whether or not to slowly build up to a full space observatory, or to just leap to a full finished product. • Now with NASA onboard, the Next step would be funding the project…. A hefty $400-$500 million!
Coming Together • Because of its big price tag, NASA wanted to take advantage of it’s world wide sources to help reduce costs. • The project was originally rejected by the House Appropriations Subcommittee in 1975. • NASA asked the European Space Research Organization (ESRO) to help with making inexpensive solar panels and help with observations and research • ESRO the offer, knocking the project’s price tag down to around $200 million • The House Appropriations Subcommittee then approved funding for the program which would start in 1977
Coming Together • Perkin-Elmer Corporation • Designed mirrors and optical assembly for the telescope • Lockhead Missiles and Space Company • Designed shuttle and support system • The Europeans • Designed the solar array that powered the Hubble while in orbit
The Hold Up • The original plan was to launch Hubble in 1983, however, there was a slight delay • The Perkin-Elmer mirror was created in 1981, but the entire housing for the mirror wasn’t put together until 1984. • The entire telescope wasn’t fully assembled until 1985 • It was 43.5 feet long • Weighed 24,500 lbs • 14 ft in diameter
Tragedy Strikes • While anticipation for the Hubble Telescope was building and the Hubble was officially ready in December 1985, NASA planned an October launch. However, tragedy then strikes the nation on January 28th 1986….
Space Shuttle Challenger Explodes • The Space shuttle explosion causes NASA to cancel any scheduled shuttle flights until 1988
The Light at the End of the Tunnel • After all of these delays, the Hubble was launched into space aboard the space shuttle Discovery on April 24th, 1988 • Its original equipment included: Wide Field/Planetary Camera (WF/PC), Goddard High Resolution Spectograph (GHRS), Faint Object Camera (FOC), Faint Object Spectograph (FOS), and High Speed Photometer (HSP) • These are all types of camera lenses designed to capture different camera angles, depths, and perspectives
One Last Problem • Shortly after the telescope started returning images to earth from space, scientists discovered that the images were very blurry. • They came to the conclusion that something was wrong with the primary mirror • This was due to a miscallibrated measuring which caused the edges of the mirror to e ground too flat, causing distortion
The Problem Solvers • As a result, COSTAR was created • Corrective Optics Space Telescope Axial Replacement • This was created to be able to replace the Hubble’s optics so that all lenses and mirrors could function properly • In December of 1993, a team of STS-61 members safely completed the mission to replace the Hubble’s optics • Broke the world record with 5 back to back space walks • The Wide Field/Planetary Camera was replaced with the Wide Field/Planetary Camera 2, which was designed to compensate for the mirror problem. • The team also performed basic maintenance on the craft, installed new solar arrays, and replaced four of Hubble's gyroscopes