luminosity

What Is The Relationship Between Luminosity And Period Of Variability?

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What Is The Relationship Between Luminosity And Period Of Variability? The longer the variability period, the more luminous the Cepheid. Through observations of Cepheid variables, astronomers have determined the distances to other galaxies. They compare the Cepheid variable’s apparent brightness with its intrinsic brightness. What is the relationship between period and luminosity of a Cepheid

Does Luminosity Decrease With Distance?

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Does Luminosity Decrease With Distance? Does luminosity decrease with distance? Notice that as the distance increases, the light must spread out over a larger surface and the surface brightness decreases in accordance with a “one over r squared” relationship. The decrease goes as r squared because the area over which the light is spread is