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I Temperature in space

  1. Jul 20, 2016 #1
    The Kelvin scale states that the temperature is a measure of the kinetic energy of the particles(molecules) of the system. But what is the temperature of a system where there are no particles...for example free space, far away from the stellar civilisation...
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  3. Jul 20, 2016 #2


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  4. Jul 20, 2016 #3


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    hi there

    for a start have a read of some better definitions of the Kelvin scale compared to what you wrote


    you will discover that temperature isn't just based on kinetic energy of the particles

  5. Jul 20, 2016 #4


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    That definition of temperature in terms of the kinetic energy of the particles in a system is incomplete; we also have to include a contribution from whatever radiation, like the cosmic microwave background, is out there. And even intergalactic space is not completely devoid of matter - there are a few stray atoms floating around, and the occasional highly energetic cosmic ray coming through.
  6. Jul 27, 2016 #5
    I have tried to think about the some thing but 'in the gaps' at molecular level of the atmosphere.
  7. Jul 27, 2016 #6


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    The temperature "in the gaps" between molecules does not exist. Temperature is a statistical property of large collections of things such as atoms and molecules. If you restrict your attention to a setting with a collection of zero objects, temperature is no longer an attribute of that collection.

    Apologies if I've misunderstood your posting.
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