Yes. If starlight passes through realtively cool hydrogen gas, the light that makes it through will have dark lines corresponding to the emission spectrum for hydrogen. The reason is that the photons that correspond to the difference in energy levels of the hydrogen atom will be absorbed (to bump the electrons up to the higher level) whereas others will not be absorbed. The actual mechanism that causes this to occur requires an understanding of quantum mechanics and is not simple.convict11 said:An emission spectrum can contain wavelengths produced when an electron goes from the third to the second leve. So could you see this like in the absorption spectrum? Why?