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abstraction > mathematical concept > number > quantity > radiation measurement > luminosity

luminosity
subject			fact

luminosity	has definition Brightness of a celestial body, measured in terms of (apparent) magnitude, absolute magnitude, or using the Sun's brightness as 1.0 on a solar scale. The luminosity of a star corresponds with its internal radiation pressure, which in turn depends on its mass.
	has definition The total amount of energy radiated by a star - that is, its true, or intrinsic, brightness.
	has definition The intrinsic brightness of a star. Usually defined in terms of absolute magnitude.
	has definition Total radiant energy output per second (absolute brightness, usually expressed in ergs s-1 or in magnitudes). L = 4πR2σT4 (see Stefan's law).
	is a kind of radiation measurement
radiation measurement	has unit radiation unit
number	has value

Kinds of luminosity :

• intrinsic luminosity (3 facts) - The amount of light an object actually emits, as opposed to how bright the object looks from Earth. An apparently bright star can be intrinsically bright and far away or intrinsically faint and nearby., The energy per second emitted by an astronomical object, analogous to the wattage of a light bulb.