Suppose a true nova has absolute magnitude Mv = -9. Suppose a kilo-nova is 1000 times more luminous. L(kilo-nova) --------------- = 1000 = -2.5 log10 [ mag(kilo-nova) - mag(nova) ] L(nova) ---> mag(kilo-nova) - mag(nova) = -7.5 ---> mag(kilo-nova) = -9 - 7.5 = -16.5