When accounting for the earth's peculiar velocity, the redshift that would pertain in that case should be used for d M , but the factor ( 1 + z ) should use the measured redshift, and another correction should be made for the peculiar velocity of the object by multiplying by ( 1 + v / c ) / ( 1 − − v / c ) , where now v is the component of the object's peculiar velocity away from us. In this way, the luminosity distance will be equal to the angular diameter distance multiplied by ( 1 + z ) 2 , where z is the measured redshift, in accordance with Etherington's reciprocity theorem (see below).