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Earth's emission spectrum

  1. Nov 29, 2009 #1

    Does anybody know if there has ever been an emission spectrum of earth recorded by one of our spacecrafts after launch from outer space? When we directly image extrasolar planets we are able to determine their atmospheric properties, etc, so can someone point me to a link which describes the Earth's emission spectrum as recorded from outer space.
  2. jcsd
  3. Nov 29, 2009 #2
    I do not think anyone ever to record such kind of spectrum. For distant planets, we don't know the compositions of , say , atmosphere so we do that job. For Earth, we are inside it so we know more without measuring from outer space.
    They may take pictures from the orbit helping drawing maps or looking for ores etc..
  4. Nov 29, 2009 #3


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    We know that there is a reflected component which resembles the emission spectrum of the sun. In addition to that, if you take the average temperature of the earth, you can find the resulting blackbody spectrum. This should be centered in the infra red. I do not know of any measurements that have been made. My lack of knowledge does not mean it has not been done.
  5. Nov 29, 2009 #4

    D H

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    NASA has been doing just that since 1975, when they launched the first Earth Radiation Budget experiment on the Nimbus 6 satellite. Instruments based on this first ERB experiment have been flown on several satellites since then.
  6. Nov 30, 2009 #5
    The EPOXI team is currently performing just such observations of the Earth, for use in exoplanet characterisation. They are using the Deep Impact spacecraft (originally used to make a close encounter with a comet), which is currently about 50 million miles from Earth. The measurements have been time-resolved imaging in several wavebands in order to observe variations as the Earth rotates. Combined, these observations may be considered to constitute a low-resolution spectrum.



    for the published data
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