"What is the fate of the world as we know it?"Tsunamis, earthquakes, volcanoes, hurricanes, pandemics, cosmic radiation, gamma bursts from space, colliding comets, and asteroids--these things used to worry us from time to time, but now they have become the background noise of our culture. Are natural calamities indeed more probable, and more frequent, than they were? Are things getting worse? Are the boundaries between natural and human-caused calamities...