In astronomy, luminosity is the amount of energy a body radiates in unit time.
Stellar luminosities are usually expressed in solar luminosities, sometimes the absolute bolometric magnitude is given instead, what is related to the luminosity.
In X-ray and radiowavelengths, luminosity is sometimes expressed in watts.
... this is seen by some as influential (to a certain limited extent) in promoting the take-up of digital television.
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