As the people of Earth set about building new floating cities to survive above the devastation, scientists studying the impacts realized that Earth had not encountered the asteroids naturally; we'd been attac. Much of the world was turned into an inhospitable wasteland by the sudden onset of impact winter. It was soon followed by a second, then a third, then more falling in a cascade of burning death and destruction. The nations of Earth were on the verge of war when the first asteroid struck.
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