Question

What does the absolute magnitude of a star depend on?

A. Brightness
B. Energy output
C. Distance from Earth
D. Color of a star

Answer 1

C. Distance from Earth

The observed brightness of a star (the apparent magnitude) to an absolute magnitude, you need to know the distance [d], to the star. Alternatively, if we know the distance and the apparent magnitude [m] of a star, we can calculate its absolute magnitude [d].

*paraphrased from "COSMOS.com"