Surface Brightness
The overall brightness of an extended astronomical object such as a galaxy, star cluster, or nebula, can be measured by its total magnitude, integrated magnitude or integrated visual magnitude; a related concept is surface brightness, which specifies the brightness of a standard-sized piece of an extended object.
Read more about Surface Brightness: General Description, Calculating Surface Brightness, Relationship To Physical Units
Famous quotes containing the words surface and/or brightness:
“Voluptuaries, consumed by their senses, always begin by flinging themselves with a great display of frenzy into an abyss. But they survive, they come to the surface again. And they develop a routine of the abyss: “It’s four o’clock ... At five I have my abyss.””
—Colette [Sidonie Gabrielle Colette] (1873–1954)
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