Here's a rundown of the seven most likely ways our world could crumble right on schedule.
For what it's worth, it's thought the dinosaurs were wiped out by an asteroid six miles across. On the off-chance that NASA's failed to spot a rock that size hurtling towards the planet, physcists have worked out that it would be impossible to nuke an Earth-killing asteroid—so it really would be curtains.
Now might be good time to point out that more countries than ever have nuclear weapons at their disposal: currently, nine countries are known to have nuclear capabilities, but only five of them are members of the safeguarding Nuclear Non-Proliferation Treaty. With North Koreathrowing rockets into the air like confetti, the nuclear threat is as present as ever.