What is the magnitude scale?
Magnitude scale is used in astronomy to classify stars brightness as seen fro earth..
In 124 Bc Hipparchus classified stars from 1 to 6 magnitude..He defined brightest stars as 1st magnitude and the most faint star we can see by naked eye as 6th magnitude.
In 1856 Norman Pogson gave it a scientific explanation
First magnitude stars are 100 times brighter tha n 6th magnitude star.. So each magnitude the difference is 5th Root of 100. THat is 2.512.
Picture explains the magnitude of commom objects.
Picture credit ces lisc ernet.in