and the wavelength shifts of the lines tell us the motion of gas. If the Sun consisted only of pure hydrogen, there would be no absorption line. This would mean that the researchers could not study the temperature or the motion of the Sun...
The depths of the absorption lines provide information about temperature, and the wavelength shifts of the lines tell us the motion of gas. If the Sun consisted only of pure hydrogen, there would be no absorption line. This would mean that the researchers could not study the temperature or ...