1. Every 30 million years, the sun's orbit around the core of the milky way causes the solar system to pass through the spiral arms of the galactic plane; within these arms, in contrast to the emptiness of deep space, lie the vast clouds of loose cosmic matter from which comets are born. Billions of these objects are captured by the sun's gravitational field during its oscillation through the spiral arms, ranging in size from the tiniest dust mote to objects the size of our own moon. In their inert state, between the outgassings that give the comet its distinctive tail, these can be some of the blackest objects in the solar system, reflecting as little as 4 percent of the sun's light. It was during one such period that the apocalypse took place. The collision happened almost without warning, the object having only been detected half an hour before impact. Astronomers at the obscure mountain observatory of ---- elected to say nothing. The comet crashed into the warm waters of the Indian Ocean, instantly sending half its volume into the atomsphere as water vapour, drowning those who did not succumb to earthquakes and tsunamis. Most of those who did survive, and they were few, were soon disheartened and died out, much in the way indigenous societies are devastated by the swift destruction of ways of life they have known for millennia. In any case, dense fogs rendered agriculture and hunting almost impossible. The exception were the bog dwellers of remote northern Europe. A hardy people, used to sodden atmospheric conditions and marginal existence, they hardly noticed the apocalypse.