How long do you think humans will be around? The answer will be subjective of course, as it's not knowable, but you can consider some factors which are objective. The Sun should have a (main sequence) life of around 10 billion years. We are already 4.5 billion years along that time frame. In another 5.5 billion years or so the Sun will become a Red Giant. It will run out of hydrogen and start burning helium. It will be cooler than it currently is but it will still be very hot. Its diameter will increase greatly and will approach the orbit of Earth. If humans haven't killed each other off or otherwise extinguished themselves by then, this should do it...unless we manage to move under water. I'm not sure how long it would take for all the waters of the oceans to evaporate. Maybe some here do know? In about 4 billion years the Andromeda Galaxy will merge with our Milky Way Galaxy. Most stars will just pass though given the vast distances. Still, there would be the potential for that to end life on Earth as well. A billion or so years after the Sun becomes a Red Giant, it will burn though the helium becoming a White Dwarf, eventually cooling off and life on Earth would freeze to death at that point. If we have gotten a handle on fusion, it's possible that we could survive without the Sun. What are your predictions for how long humans will be around on Earth (as opposed to leaving Earth)?