When describing the brightness of celestial objects, what does 'absolute magnitude' signify?

'Absolute magnitude' refers to the intrinsic brightness of a celestial object, such as a star, as measured at a standardized distance of 10 parsecs (approximately 32.6 light-years) from Earth. This measurement provides a way to compare the true brightness of different stars without the influence of distance or atmospheric effects that can alter their apparent brightness when viewed from Earth. By using this standardized distance, astronomers can ascertain how bright a star would appear if it were placed at this reference point, enabling more accurate comparisons among celestial objects.

This concept is crucial in understanding the properties of stars, as it helps distinguish between how bright a star looks from Earth (apparent magnitude) and how bright it really is intrinsically. Thus, 'absolute magnitude' provides a clear understanding of a star's true luminosity independent of its distance from the observer.