What is the difference between first magnitude and 29th magnitude?

Answer 1

Brightness. A 1st magnitude star is one of the brightest stars in the sky. Things at 7th magnitude are just barely visible to the naked eye, and objects at 29th magnitude are barely detectable even with the largest telescopes.

Mathematically, as you move up a magnitude the next star is about 2.512 times

brighter. So you need to keep multiplying until you've gone from magnitude 29

right up to 1st magnitude.

In fact an increase in brightness of five magnitudes is an increase of exactly 100 times.

So, in this case the answer is :

100 x 100 x 100 x 100 x 100 x about 15.85

That's about: 158,500,000,000 times brighter.

Answer 2

First magnitude stars are the brightest stars visible to the naked eye, while 29th magnitude stars are extremely faint and require powerful telescopes to be detected. The brightness scale is logarithmic, with each magnitude representing a difference of about 2.5 times in brightness.