A question about the sun and blackbody

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The spectrum of sunlight closely resembles that of a blackbody because the sun acts as a good approximation of one. The distribution of photons emitted by the sun aligns with the Planck distribution, primarily due to its high temperature and size. Most of the sun's emission is continuous spectrum radiation generated in the photosphere, where photons are absorbed and reemitted in equilibrium. This process results in minimal absorption or emission lines, leading to a spectrum that is predominantly blackbody-like. Overall, the sun's characteristics contribute to its similar spectral output.
wenty
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Why is the spectrum of sunligt similar to that of a blackbody?
 
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wenty said:
Why is the spectrum of sunligt similar to that of a blackbody?

Because the sun is a reasonable approximation of a blackbody.
 
Because the observed wavelength (or frequency) distribution of photons from the Sun is the same as that of a blackbody, to the zeroth order (using total energy as the measure).
 
Because the sun is a big, hot thing, and the Planck distributed radiation swamps the line and band emissions.

Jerry Abbott
 
A little more detailed explanation is that most of the emmision from the sun is continuous spectrum radiation produced deeper in the photosphere where the photons are absorbed and reemitted about equally, so that the two processes are in equilibrium, which is what occurs in a blackbody. Very little of the radiation is absorbed (fraunhofer lines) or added to produce emission lines.
 
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