Suppose that you're on board a small space station orbiting the Earth and you learn that an Asteroid of mammoth size is about to collide with the planet. No one can stop because it is too close and coming too fast. You can't be rescued because there is no way to get a launch vehicle ready in time. All you can do is monitor the destruction and watch as civilization collapses as everything that had been built is ruined.
So there you are, safe, on the space station... except, your supplies are limited. You air is limited. And you won't be going home soon. How do you handle the problem of survival?