|Our sun in comparison to just a small section of this enormous|
star. If you were to carry it out past the edge of the screen, you'd
see how ridiculously huge this star happens to be.
So the thing that keeps a star from just flying apart is gravity. In the case of VY Canis Majoris, there is so much mass that when the fusion stops going, gravity is just going to kind of take over and crush the core of the star into a black hole. Black holes are things that our brightest physicists don't really understand. Places where infinite gravity takes over and time stops and light can't even escape.