The end of the world is near--December 21, 2012, to be exact--according to theories based on a purported ancient Maya prediction and fanned by the marketing machine behind the soon-to-be-released 2012 movie. (See "2012 Prophecies Sparking Real Fears, Suicide Warnings
.")
In some 2012 doomsday prophecies, the Earth becomes a deathtrap as it
undergoes a "pole shift," courtesy of an asteroid impact (illustrated
above), a rare alignment with the center of the Milky Way, and/or
massive solar radiation destabilizing the inner Earth by heating it.
The planet's crust and mantle will suddenly shift, spinning around
Earth's liquid-iron outer core and sending cities crashing into the
sea. (Interactive: pole shift theories illustrated.)
Princeton University geologist Adam Maloof has extensively studied pole shifts, and tackles this 2012 myth in 2012: Countdown to Armageddon, a National Geographic Channel documentary airing Sunday, November 8.
Maloof says magnetic evidence in rocks confirms that continents have
undergone such drastic rearrangement, but the process took millions of
years--slow enough that humanity wouldn't have felt the motion (quick guide to plate tectonics).
(The National Geographic Society owns National Geographic News and part-owns the National Geographic Channel.)
Source : http://news.nationalgeographic.com/news/2009/11/photogalleries/2012-movie-end-of-the-world-pictures/index.html