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《美国空间6.5米望远镜在NASA休斯顿空间中心进行最后三个月低温试验》

  • 来源专题：天文仪器与技术信息
  • 编译者： zwg@niaot.ac.cn
  • 发布时间：2017-06-29

  • NASA’s James Webb Space Telescope was placed in Johnson Space Center’s historic Chamber A on June 20, 2017, to prepare for its final three months of testing in a cryogenic vacuum that mimics temperatures in space.

    Engineers will perform the test to prove that the telescope can operate in space at these temperatures. Chamber A will simulate an environment where the telescope will experience extreme cold -- around 37 Kelvin (minus 236 degrees Celsius or minus 393 degrees Fahrenheit).

    In space, the telescope must be kept extremely cold, in order to be able to detect the infrared light from very faint, distant objects. To protect the telescope from external sources of light and heat (like the sun, Earth, and moon), as well as from heat emitted by the observatory, a five-layer, tennis court-sized sunshield acts like a parasol that provides shade. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 185 degrees Fahrenheit) and a cold side (400 degrees below zero). The sunshield blocks sunlight from interfering with the sensitive telescope instruments.

    The James Webb Space Telescope is the scientific successor to NASA's Hubble Space Telescope. It will be the most powerful space telescope ever built. Webb is an international project led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.

  • 原文来源：https://www.nasa.gov/feature/goddard/2017/nasas-webb-telescope-gets-freezing-summertime-lodging-in-houston
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  • 《美国空间6.5米望远镜到达NASA休斯顿空间中心》
    • 来源专题：天文仪器与技术信息
    • 编译者：zwg@niaot.ac.cn
    • 发布时间：2017-05-12
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  • 《美国NASA对空间6.5米望远镜（JWST）进行新的振动试验》
    • 来源专题：天文仪器与技术信息
    • 编译者：zwg@niaot.ac.cn
    • 发布时间：2017-02-23
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