There is currently a growing number of doomsday believers who believe the world will end in December 2012. They explain that prophecies stemming from sources as diverse as the Mayan calendar and Nostradamus predict that human civilization will either be destroyed or dramatically changed at that time because a comet will strike the planet. Biblical numerologist Harold Camping has made a similar prediction, except that he places the date at October 21, 2011. Astronomers tracking comets, however, have found no evidence that any of the comets in our solar system are heading our way any time soon.