How are masses of stars calculated

Question

How are masses of stars calculated

Answer 1

If u examine the light spectrum of a star you can determine the distance it is from Earth and it's composition.  Given the composition ,distance and brightness u can calculate the mass.

Answer 2

Yeah, well spectra.

But first, they had to figure out what each kind of star weighed. To do that, you find one with a companion.  With two objects you can figure out the mass of both, the distance between them, all sorts of good stuff.  And you get the spectra of it, and think about all of the above good stuff.

Then when you see a lone star (not just Texas) you can get it's spectra and say, you need to go on a diet!  Wait a minute.  That's me.

Answer 3

Basically, by looking at the color, the distance and the brightness.