 The apparent brightness of a star is expressed in terms of its apparent magnitude . It is a function of the star 's luminosity , its distance from Earth , and the altering of the star 's light as it passes through Earth 's atmosphere . Intrinsic or absolute magnitude is directly related to a star 's luminosity , and is what the apparent magnitude a star would be if the distance between the Earth and the star were 10 parsecs ( 32 @.@ 6 light @-@ years ) . 
 The apparent brightness of a star is expressed in terms of its apparent magnitude . It <a href='drop_aux' title='1'><mark>is</mark></a>a function of the star <a href='null_genetive' title='2'><mark>'s</mark></a>luminosity , its distance from Earth , and the altering of the star <a href='null_genetive' title='3'><mark>'s</mark></a>light as it <a href='uninflect' title='4'><mark>passes</mark></a> through Earth <a href='null_genetive' title='5'><mark>'s</mark></a>atmosphere . Intrinsic or absolute magnitude is directly related to a star <a href='null_genetive' title='6'><mark>'s</mark></a>luminosity , and is what the apparent magnitude a star would be if the distance between the Earth and the star <a href='uninflect' title='7'><mark>were</mark></a> 10 parsecs ( 32 @.@ 6 light @-@ years ) . 
Da apparent brightness of a star is expressed in terms of its apparent magnitude . It a function of the star  luminosity , its distance from Earth , and the altering of tdastar  light as it pass through Earth  atmosphere . Intrinsic or absolute magnitude is directly related to a star  luminosity , and is what the apparent magnitude a star would b if thdaistance between thedarth and the star was 10 parsecs ( 32 @.@ 6 light @-@ years ) .