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radiation measurement comparison table
Subject has specie has width has wavelength occurs in has definition
color     
luminosity    Total radiant energy output per second (absolute brightness, usually expressed in ergs s-1 or in magnitudes). L = 4πR2σT4 (see Stefan's law).
magnitude    A measure. on a logarithmic scale, used to indicate the brightness of a celestial object. A 1-magnitude difference in brightness between two stars corresponds to a difference in luminosity by 100.4 or 2.51; 5 magnitudes corresponds to factor of 100 in luminosity.
spectral feature    A feature in the spectra of a celestial object which occurs at a specific wavelength or range of wavelengths

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