I would be highly interested in learning how the scale height affects the spectrum from the observers point of view here on Earth. The center-to-limb variation (CLV) reveals a significant difference in temperature of about 1400K between limb and the central zone of the disk.
Normally, the solar spectral irradiance is the integral of all emissions from the disk. Due to the CLV, this will not result in a nice Planck distribution, albeit, it is pretty close -- the difference in effective temperature and Planck temperature is only about 70K, or so.
If, however, a spectral irradiance observation is obtained of only a small region of the Sun, then a much nicer Planck distribution should be found, right?
What is unclear to me is whether or not the central disk temperature of 6400K will produce a very nice Planck distribution for that temperature (ignoring the emission & absorption bands)? In other words, would scattering or other effects [observable to the bottom of the photosphere] complicate the Planck result?
The advancement of heliochromology appreciates all
scientific comments. [Reasonable fluff is acceptable as the textbook draft is still rather thin.
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