WHAT'S THE WORLD COMING TO? FIRST, ASTROPHYSIcists said comets killed the dinosaurs. Then they implicated asteroids in numerous other mass extinctions throughout the earth's history, setting the stage for the awful news in October that the comet Swift-Tuttle might crash into the planet in the year 2126.
The buildup to astronomical apocalypse grows ever more dramatic. At the American Geophysical Union's meeting in San Francisco, some respected researchers suggested that a large space rock 10 to 20 km (6 to 12 miles) in diameter slammed into the earth 250 million years ago and set whole continents adrift. The announcement by Michael...