Question: How big is an average star in our galaxy?

Zsolt Keszthelyi answered on 20 Nov 2020:

It turns out that average stars are smaller than the Sun. This has to do with how stars form. They originate from the collapse of a cloud, which then falls into small clumps, and these clumps will become stars. Sometimes, clumps can lead to massive stars (the ones that explode by the end of their lives) but more generally the clumps form Sun-like stars. It seems that in nature it is easier to form these kinds of stars. So the average star would be just a little bit less massive than the Sun. But for 1 in every 100 or so clumps, you could also find a star forming which is 40 times more massive than the Sun. Then the evolution of these stars is shaped by many factors, including their winds which will remove some of the mass (or in some cases, most of the mass).