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:
“In the cold of Europe, under prudish northern fogs, except when slaughter is afoot, you only glimpse the crawling cruelty of your fellow men. But their rottenness rises to the surface as soon as they are tickled by the hideous fevers of the tropics.”
—Louis-Ferdinand Céline (1894–1961)
“Awareness of the stars and their light pervades the Koran, which reflects the brightness of the heavenly bodies in many verses. The blossoming of mathematics and astronomy was a natural consequence of this awareness. Understanding the cosmos and the movements of the stars means understanding the marvels created by Allah. There would be no persecuted Galileo in Islam, because Islam, unlike Christianity, did not force people to believe in a “fixed” heaven.”
—Fatima Mernissi, Moroccan sociologist. Islam and Democracy, ch. 9, Addison-Wesley Publishing Co. (Trans. 1992)