Intrinsic brightness

Astronomers use the term intrinsic brightness to refer to how bright a star would be without the effects of distance or absorption due to interstellar dust or gas. While a bright distant star's apparent brightness might be less than a nearby dim star, due to the inverse square law for brightness, astronomers can discuss its intrinsic brightness meaning how bright the stars would be at a common distance. A star's intrinsic brightness is measured by its absolute magnitude.