What is the magnitude scale in astronomy?

1 Answer

a logarithmic scale to tell brightness of a star.


about 2000 years back Hipparchus made the idea of a scale.
brightest stars were called magnitude 1. Most faint stars were called magnitude 6..So a magnitude of 1 means brightness increase of 2.5..THis scale works out i n reverse order.More the number less the brightness.
modern electronic instruments came and the scale was extended i nto minus side for brightener objects.
So sun is -26.73
Sirius -1.46
Canpopus(Carina) -0.72
Venus -4.