I was thinking of a situation, in which a band of hunter gatherers goes into a cave, and while they are in the cave an asteroid crashes into the Earth, causing the rock that the cave is in to be ejected at not only the escape velocity of the Earth, but also the escape velocity of the solar system.
During the brief period of time that the rock is still in Earths Atmosphere a smaller rock gets knocked into the entrance of the cave, sealing the atmosphere of the cave off from the outside universe, so that the atmosphere does not escape into space during the time the rock is in space.
For many generations the hunter gatherers survive by eating the organisms in the cave, until eventually the rock that the cave is in crashes into another planet that happens to have Earth like conditions, and has life.
The rocks that sealed the hunter gathers in the cave for many generations are ejected from the entrance to the cave when the rock crashes into the planet, allowing the hunter gatherers to leave the cave, and colonize the planet.
Would this situation be possible?