Star Bright

In a previous posting we looked at the fact that not all stars are the same colour, this time we’ll take a look at their brightness. You will have noticed (I hope) that when looking at Orion, not all the stars are of the same brightness. Betelgeuse (top left) and Rigel (bottom right) are much brighter than the stars top right and bottom left which are in turn brighter than the three stars that make up the “belt”!

So, why are some brighter than others? Are they closer? Are they Bigger? Are they hotter? Are they all three? Take some time to think about it (and maybe look at some other stars) and we’ll talk about it in the next posting.

Image credit: Wikipedia - Mouser Williams