How many times brighter is a star with apparent magnitude 6 than a star with apparent magnitude 21?
A) 10,000 times brighter
B) 1,000 times brighter
C) 1,000,000 times brighter
D) It is not brighter

Question

Quizplus · Accepted Answer

The brightness difference between each magnitude is 2.512 (Pogson's Ratio). To find the brightness difference over 15 magnitudes (21 - 6 = 15), you calculate 2.512^15, which is approximately 1,000,000 times brighter.

How Many Times Brighter Is a Star with Apparent Magnitude