the differences between the different spectral types of stars are primarily due to ionization state.
the differences between the different spectral types of stars are primarily due to ionization state.
the differences between the different spectral types of stars are primarily due to?
ionization state
in astronomy, stellar classification is the classification of stars based on their spectral characteristics. electromagnetic radiation from the star is analyzed by splitting it with a prism or diffraction grating into a spectrum exhibiting the rainbow of colors interspersed with spectral lines. each line indicates a particular chemical element or molecule, with the line strength indicating the abundance of that element. the strengths of the different spectral lines vary mainly due to the temperature of the photosphere, although in some cases there are true abundance differences. the "spectral class" of a star is a short code primarily summarizing the ionization state, giving an objective measure of the photosphere's temperature.
stellar classification
the relative numbers of blue, yellow, and red supergiants is an indicator of the speed of stellar evolution and is used as a powerful test of models of the evolution of massive stars.









































section::::properties.:luminosity.









































the supergiants lie more or less on a horizontal band occupying the entire upper portion of the hr diagram, but there are some variations at different spectral types. these variations are due partly to different methods for assigning luminosity classes at different spectral types, and partly to actual physical differences in the stars.
supergiant star