Absolute Magnitude is a measure of the intrinsic brightness of a celestial object, such as a star or galaxy, as it would appear at a standard distance of 10 parsecs (about 32.6 light-years) from Earth. This allows astronomers to compare the true brightness of different objects without the effects of distance or interstellar dust. By using Absolute Magnitude, scientists can determine how much light a star emits and classify it accordingly. This measurement is crucial for understanding the life cycles of stars and the structure of the universe, as it helps in estimating distances and the composition of various celestial bodies.