Absolute Magnitude of a Star - with luminosity distance

Description

Absolute magnitude is the measure of a celestial object’s intrinsic brightness. It is the hypothetical apparent magnitude of an object at a standard luminosity distance of exactly 10.0 parsecs or about 32.6 light years from the observer, assuming no astronomical extinction of starlight. This allows the true energy output of astronomical objects to be compared without regard to their variable distances. As with all astronomical magnitudes, the absolute magnitude can be specified for different wavelength intervals; for stars the most commonly quoted absolute magnitude is the absolute visual magnitude, which is the absolute magnitude in the visual (V) band of the UBV system.

For a negligible extinction, one can compute the absolute magnitude of an object given its apparent magnitude and luminosity distance, as shown.