color-magnitude diagram
(CMD)
(diagram relating color to luminosity)
A color-magnitude diagram (CMD) is a diagram analogous to an
H-R diagram, but plotting color against absolute magnitude
(luminosity). It is often used for galaxies
and groups of stars such as globular clusters.
(stars,galaxies,astrophysics,wavelength,luminosity,diagram,color,magnitude)
http://en.wikipedia.org/wiki/Galaxy_color-magnitude_diagram
http://coolwiki.ipac.caltech.edu/index.php/Color-Magnitude_and_Color-Color_plots
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