Galaxy_color–magnitude_diagram
Galaxy color–magnitude diagram
Chart depicting the relationship between brightness and mass of large star systems
The galaxy color–magnitude diagram shows the relationship between absolute magnitude (a measure of luminosity) and mass of galaxies. A preliminary description of the three areas of this diagram was made in 2003 by Eric F. Bell et al. from the COMBO-17 survey[1] that clarified the bimodal distribution of red and blue galaxies as seen in the analysis of Sloan Digital Sky Survey data[2] and even in de Vaucouleurs's 1961 analyses of galaxy morphology.[3]