It's odd the little bits GLPers get right. I had one come up with the concept of a space elevator from something I posted a little while ago. The sun is gravitationally contained, mostly. Occasionally a streamer snaps loose and causes the nation of Canada to stop working but that's another story.

Once I saw a calculation of how long it could burn given it's energy output and mass (I'm too lazy to google) and it would only be a few hundred years before it's just a ball of steam. Furthermore oxygen is a very rare thing in the universe; there are no plants in space and left to it's own devices oxygen will combine with something (anything) and stay there indefinitely.