The bolometric magnitude of a star is a measure of the total radiation of a star emitted across all wavelengths of the electromagnetic spectrum.

The absolute bolometric magnitude ( abm) is the bolometric magnitude the star would have if it was placed at a distance of 10 parsecs from Earth.

Visible light makes up a very small part of the entire electromagnetic spectrum. To determine the bolometric magnitude of a star, we must consider the radiation from all wavelengths.