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有人操控宇宙飞行


 2006-8-27 16:02:36    

Human spaceflight

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    有人操控宇宙飞行是载有工作人员并和可能的乘客的太空探索飞行,其与机器化的空间探索或远程控制的非人类太空飞行相对。

    Human spaceflight is space exploration with a human crew and possibly passengers, which is in contrast to robotic space probes or remotely-controlled unmanned space missions.

    On occasion, passengers of other species have ridden aboard spacecraft, although not all survived the return to earth. Dogs, not humans, were the first large mammals launched from Earth. The first human spaceflight was Vostok 1 on April 12, 1961; Soviet cosmonaut Yuri Gagarin made one orbit around the earth. Perhaps the highest of Earth orbits was Gemini 11 in 1966, which reached a height of 1374 km. The Space Shuttle on the missions to launch and service the Hubble Space Telescope has also reached high earth orbit at an altitude of around 600 km.

    The destination of human spaceflight missions beyond Earth orbit has only been the Moon. On the first such mission, Apollo 8, the crew orbited the Moon. Apollo 10 was the next mission, and it tested the lunar landing craft in lunar orbit without actually landing. The six missions that landed were Apollo 11-17, excluding Apollo 13. On each mission, two of the three astronauts involved landed on the moon; thus, in the late 1960s and early 1970s NASA's Apollo program landed twelve men on the Moon¡ª¡ªreturning them all to Earth.

    As of 2005 piloted space missions have been carried out by Russia, the People's Republic of China, and the United States. Missions carried out by the United States are both governmental (NASA) and civilian (Scaled Composites, a California-based company). Brazil, Canada, Europe, India, Japan and Ukraine also have active space programs. The Indian Parliament recently sanctioned funds to the Indian Space Research Organization for a human spaceflight by 2008 (although the programme has now been scaled down to start with an unmanned orbiting satellite for surveying¡ª¡ªsee Chandrayan). Japan has announced a program to place a person on the moon by 2025.

    Currently the following spacecrafts and spaceports are used: International Space Station (includes Soyuz TMA as an emergency lander; normal crew transport with the following two spacecraft) Soyuz TMA with Soyuz launch vehicle - Baikonur Cosmodrome Space Shuttle - John F. Kennedy Space Center Shenzhou spacecraft with Long March rocket - Jiuquan Satellite Launch Center Scaled Composites SpaceShipOne with Scaled Composites White Knight (the latter does not enter space itself) - Mojave Spaceport

    In an attempt to win the $10 million X-Prize, numerous private companies attempted to build their own manned spacecraft capable of repeated sub-orbital flights. The first private spaceflight took place on June 21, 2004, when SpaceShipOne conducted a sub-orbital flight. With its second flight within one week, SpaceShipOne captured the prize on October 4, 2004.

    NASA uses the term "human spaceflight" to refer to its programme of launching people into space. Traditionally, these endeavours have been referred to as "manned space missions". The term "manned" is accurate in terms of gender when speaking of all U.S. spaceflight programs before the Space Shuttle program and Soviet spaceflights before Vostok 6. Although it only denotes gender in one of several definitions of the word, the term "manned" is considered sexist by some, and they may prefer to use the term "crewed"' or "piloted space missions."

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