Solar Spectrum

On Wednesday, April 5, 2006 2:38:02 AM UTC-7, Gautham Ram wrote:
We know that the sun emits a line absorption spectrum(certain
wavelengths of light are absorbed by the sun's atmosphere and so are
not emitted by the sun) Well that's fine but the elements in the Sun's
atmosphere(hydrogen and helium atoms) absorb the wavelength and hence
the energy contained with the particular wavelength... So they must be
heated to incandescence and thus emit light corresponding to their own
wavelength(which is the same as the one that they absorbed).. Following
this line of reasoning, we come to the conclusion that there must not
be any absorbtion lines in the spectrum of the sun which is not
true..So can anybody explain this to me?

I certainly can't explain it, but it'll be interesting to see what the next
close encounter probe can help deduce as to what makes the atmosphere of t
hat sun so much hotter than its highly problematic photosphere surface.

"The coolest layer of the Sun is a temperature minimum region about 500 km
above the photosphere, with a temperature of about 4,100 K.[63] This part o
f the Sun is cool enough to allow simple molecules such as carbon monoxide
and water, which can be detected by their absorption spectra.[69]"

Large dark spots and especially those vast gaping dark areas of relative th
ermal darkness can fall below 3300 K.