Hello people, I was wondering, why the absence of certain frequencies in the sun spectrum (fraunhofer lines) is so strong? In all pictures I have seen so far these lines are very dark, so there is nothing reaching us at these frequencies. Why is that? The absorption occurs in the solar atmosphere. But also, there must be a re-emission of these missing frequencies, and the re-emission occurs in all spatial directions equally. Therefore some of the light should be able to exit the solar atmosphere, because the probability of going back to the sun equals the probability of going the other way around.