Luminosity

Measurement of radiant electromagnetic power emitted by an object

Luminosity is an absolute measure of radiated electromagnetic energy per unit time, and is synonymous with the radiant power emitted by a light-emitting object. In astronomy, luminosity is the total amount of electromagnetic energy emitted per unit of time by a star, galaxy, or other luminous astronomical object. In SI units, luminosity is measured in joules per second, or watts.

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