Absolute Magnitude (Absolute Brightness)
Absolute Magnitude is a measure of the true brightness of an object. The absolute magnitude or brightness of an object is the apparent magnitude or brightness it would have if it were located exactly 10 parsecs (32.6 light-years) away from an observer. It allows the true brightness of objects to be compared to each other as though they were the same distance away. This corrects for a very bright distant object looking dimmer than an object that is much closer.