<P> Absolute magnitude is a measure of the luminosity of a celestial object , on a logarithmic astronomical magnitude scale . An object 's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if were viewed from a distance of exactly 10 parsecs ( 32.6 light years ) , with no extinction ( or dimming ) of its light due to absorption by interstellar dust particles . By hypothetically placing all objects at a standard reference distance from the observer , their luminosities can be directly compared on a magnitude scale . As with all astronomical magnitudes , the absolute magnitude can be specified for different wavelength ranges corresponding to specified filter bands or passbands ; for stars a commonly quoted absolute magnitude is the absolute visual magnitude , which uses the visual ( V ) band of the spectrum ( in the UBV photometric system ) . Absolute magnitudes are denoted by a capital M , with a subscript representing the filter band used for measurement , such as M for absolute magnitude in the V band . </P>
<P> Absolute magnitude is a measure of the luminosity of a celestial object , on a logarithmic astronomical magnitude scale . An object 's absolute magnitude is defined to be equal to the apparent magnitude that the object would have if were viewed from a distance of exactly 10 parsecs ( 32.6 light years ) , with no extinction ( or dimming ) of its light due to absorption by interstellar dust particles . By hypothetically placing all objects at a standard reference distance from the observer , their luminosities can be directly compared on a magnitude scale . As with all astronomical magnitudes , the absolute magnitude can be specified for different wavelength ranges corresponding to specified filter bands or passbands ; for stars a commonly quoted absolute magnitude is the absolute visual magnitude , which uses the visual ( V ) band of the spectrum ( in the UBV photometric system ) . Absolute magnitudes are denoted by a capital M , with a subscript representing the filter band used for measurement , such as M for absolute magnitude in the V band . </P>
absolute magnitude is defined as the apparent magnitude that a star would have if
absolute magnitude is defined as the apparent magnitude that a star would have if
if were viewed from a distance of exactly 10 parsecs ( 32.6 light years )
if were viewed from a distance of exactly 10 parsecs ( 32.6 light years )