yeah there will probably be some big war, but more certain is that our sun will die. part of the death process of a sun involves it explanding, our planet is close enought to our sun so that, when, in a few million years [cant remember the exact date -- but its along long way away!] the sun dies, we will die with it, if mankind has managed to escape to another planet, still inside the solar system, they will find darkness and eternal coldness, our solar system would freeze, so humans have no chance of survival unless they fly to another solar system, and at the moment, it would take soooo long to get there, you'd be dead of old age before you got anywhere near your destination!