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B The Stefan-Boltzmann Law and Sunspots

  1. Jul 13, 2018 #1
    The Stefan-Boltzmann Law

    Question: Is this law proven to be true? If so, then what about sunspots?

    The surface of the sun is roughly double the temperature of an umbra which means it should be 16 times brighter according to this law. It isn't.

    The luminosity of the photosphere is 10,000 times the luminosity (1,000,000%) of a sunspot umbra. That seems like a huge discrepancy. Could something else be at play? Could sunspots be a different element and/or a different state of matter?

    I know current theory blames magnetism. In order for that to be the mitigating factor wouldn't sunspots have to generate their own magnetic field? Can hydrogen do that?
    Just asking.

    Doc Holiday
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  3. Jul 13, 2018 #2


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    In science you never ”prove” anything. You test your theory by checking whether the predictions it makes match your experimental result. In the case of the Stefan-Boltzmann law, it has been extremely well tested and found accurate.

    What about them? The physics of sunspots are also well understood. I suggest reading a textbook on stellar physics rather than making assumptions.
  4. Jul 13, 2018 #3


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    @K. Doc Holiday could you please provide sources for those numbers so we can tell if you have properly interpreted what you are reading.
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