Brightness and Magnitude
Brightness and Magnitude
The brightness ratio between two celestial objects, the flux ratio, is defined as =, where and are the apparent magnitudes of the objects. The magnitude scale is a much more convenient way to express brightness measurements than using actual brightness measurements that use much larger numbers. Brightness and magnitude are important introductory topics in basic astronomy.
ϕ
1
ϕ
2
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m
1
m
2
2.5
10
m
1
m
2