The Sun currently shines because H is being burned to He, and it has been doing this for about 4.57 Ga. But when we analyze the Sun's atmosphere, we do not find unusually large amounts of He. Why not? ...
Determining effective temperature of a star is in general a non-trivial task. Simple reason for this is that we can only study the electromagnetic radiation from a star, but not the temperature ...
This is a question about the basics of astronomy, which I have never happened to see a good discussion for. It is about how well would we be able to measure effective temperature of a star, if we had ...