Explain how the elements present on the surface of a star can be identified using bright line spectra

Certain elements (gases) have their own specific and unique brighline spectra, so to identify different gases on the surface of a star, all scientists have to do is to look at the brightline spectra that those gases emit and compare to the spectra of the known gases on earth. If the spectra from the gas on the star matches the spectra of the known gas on earth, then there is no problem in identifying the gas.