Sun spectra and Doppler shift

Has someone ever truly questioned how some dark line appear in the Sun spectra ?
As far in solar atmosphere the temperature is never under 3700 K, how is possible to have the absorption line of neutral hydrogen?
How is possible to have the neutral line of Sodium, Iron, etc.
Is there a cloud of neutral matter between Sun and Earth and astronomer did not observe it? Is it such cloud at 3700 K a cold cloud of gas?
Maybe is there some dark matter which generate our dark lines in solar spectra …

When Doppler effect and the measurements of solar rotation are analyzed the situation is even more strange ….
If this neutral matter is somewhere in solar atmosphere .. what has this to do with Sun rotation movement ?
Can I infer the rotation of Earth based on the movements of clouds?
More info at :

http://elkadot.com/index.php/en/books/astrophysics/solar-spectra-and-doppler-shift

Best regards,

Sorin Cosofret

Last edited by sorincosofret; 10/24/15 02:42 PM.