it is known that the photoshere is closer to the core of sun than the chromosphere and the corona,but why is it that the chromosphere and then corona are of severe temperatures higher than the photosphere?pls help me

Hello my friend!
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The answer to your question is: nobody know in fact until now! This is an open problem in Astrophysics, but there are some hypothesis for the "Coronal Heating Problem" - Corona - Wikipedia, the free encyclopedia -, how the Alfvén Waves - Alfvén wave - Wikipedia, the free encyclopedia -, or solar nanoflares - http://www.scientificblogging.com/da...noflares_matte .
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It's a good, deep and vast question. Truthful food for thought!
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[]'s!

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