The six Orbiters built by NASA for the Space Transportation System are:
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<b>Enterprise</b> (OV-101): built as a test vehicle in 1977. Enterprise was originally supposed to be called ÒConstitution,Ó to mark the 200th anniversary of the founding of the U.S. However, fans of the television series Star Trek conducted a letter-writing campaign to the White House. The campaign urged the President to have the first shuttle named after the Enterprise on the TV show. Enterprise was used in landing tests, but was never sent to space. In 1985, it was sent to the National Air and Space Museum at the Smithsonian Institute in Washington as an exhibit piece.
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<b>Columbia</b> (OV-102): is the oldest Orbiter in the STS fleet. Columbia was named after an American ship that, in 1792, travelled through dangerous inland waters to explore British Columbia, Washington, and Oregon. It was the Orbiter used in the first Shuttle flight to space on April 12, 1981. On its second mission on November 12, 1981, Columbia became the first vehicle ever to fly to space twice.
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<b>Challenger</b> (OV-99): was the second Orbiter to travel to space. It was named after a British naval research ship that sailed the Pacific and Atlantic Ocean in the late 19th century. Its airframe was originally built as a test vehicle, but was later modified for use in space. Its first mission was on April 4, 1983. On January 28, 1986, it was destroyed due to a SRB malfunction during its tenth flight.
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<b>Discovery</b> (OV-104): had its first flight on August 30, 1984. It was named after one of the ships sailed by British explorer Captain James Cook when he explored the northwest coast of North America in the late 1700s.
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<b>Atlantis</b> (OV-104): first flew to space on October 3, 1985. It was named after the first U.S. sailing vessel used for <a href="Glossary">oceanographic</a> research.
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<b>Endeavour</b> (OV-105): was built as a replacement vehicle for Challenger. It was named after the first ship captained by James Cook, who sailed the South Pacific on it and discovered Hawaii. Endeavour had its first mission on May 8, 1992.
