Hi pf. As I understand we know what a star is made of by looking at the absorption spectrum from a star. Since a star is a black-body it gives out a continuous spectrum of light but as this light passes through the Sun's atmosphere, certain wavelengths are absorbed depending on what the star is made of. My question is, how do we know what the rest of the star is made of? Surely from this method you only know what elements are in the atmosphere of the star?