Yeah, I often wondered what would happen when our sun ran out of hydrogen and consumed the earth. Perhaps we'd have the technology to leave by then, but doesn't the bible say "the earth will endure forever" or was that not true? What happens to us when our galaxy collides with andromeda? Or when the universe has expanded to the point where stars can no longer exist? Sure, that's all a long way off, but not as far off as forever. It was deeply unsatisfying to imagine that god would have to intervene periodically to keep things running.
The funny thing is that the 2nd law of thermodynamics (the same one that they love to use to "prove" that life cannot form without divine intervention - forgetting that the earth is not a closed system) proves that nothing can last forever. Eventually everything will reach a state of maximum entropy.