Is There a Balance Between Gravity and Explosion?

Pulsating stars swing back and forth between squishing andexploding. People are building models to try to explain this kind of thing. And it's a great way to probe what's going on inside the star also. In extreme cases, it can be really dramatic. One example is called a flare star. These kinds of stars can grow in brightness by a factor of six and then fade back down. That's huge.