What Can the Brightness Ratio of Stars Tell Us?

If light from one star is 251 times brighter (has 251 times more flux) than light from another star, what is their difference in magnitude?

A) 2.51

B) 5.14

C) 251

D) 50,000

Answer:

The magnitude difference between two stars that have a brightness ratio of 251 is approximately 5.14.

Understanding the brightness ratio of stars can provide valuable insights into their magnitudes and relative brightness. In astronomy, the magnitude difference between two stars can be calculated using a logarithmic expression that relates the ratio of their brightness (or flux).

The formula to calculate the magnitude difference between two stars is: m1 - m2 = -2.5 log (b1/b2), where m1 and m2 are the apparent magnitudes of the stars, and b1 and b2 are their brightness ratios. Therefore, if one star is 251 times brighter than another, the difference in magnitude would be approximately 5.14.

Magnitude is an inverse measure of brightness, where lower numerical values indicate brighter objects. This scale allows astronomers to compare the brightness of stars and celestial bodies more easily across different wavelengths.

By understanding and utilizing the concept of magnitude difference, astronomers can gain deeper insights into the relative brightness and properties of stars in the night sky.