The bad news is tens of millions of people along the eastern seaboard of the United States and Canada may drown if the slow slippage of a volcano off north Africa becomes a cataclysmic collapse. But the good news is the world is not likely to be destroyed by an asteroid any time soon.Scientist Bill McGuire told that some time in the next few thousand years the western flank of the Cumbre Vieja volcano on the Canary Island of La Palma will collapse, sending walls of water 100 meters high racing across the Atlantic. A chunk of the volcano [Cumbre...