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distance modulus




The difference between the apparent magnitude (m) of an astronomical object, such as star, and its absolute magnitude (M). The distance modulus is given by

m - M = 5 log d - 5

where d is the distance in parsecs.

Rearranging this enables d to be calculated from the formula

d = 10(m - M + 5)/5


Related category

   • ASTRONOMICAL QUANTITIES