Distance modulus

The distance modulus is a way of expressing distances that is often used in astronomy. It describes distances on a logarithmic scale based on the astronomical magnitude system.

The distance modulus ${\displaystyle \mu =m-M}$ is the difference between the apparent magnitude ${\displaystyle m}$ (ideally, corrected from the effects of interstellar absorption) and the absolute magnitude ${\displaystyle M}$ of an astronomical object. It is related to the distance ${\displaystyle d}$ in parsecs by:

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