NASA declared that there are some planets beyond Saturn which are not known yet. In fact, NASA found one planet near SATURN which is approximately 100k miles away from SATURN. They named it PLANET X NIBIRU.
Its been scheduled by NASA that this will pass between JUPITAR and MARS on 21st December 2012. The main point behind the 21st Dec 2012 is that there is a danger that when this passes near the Earth on that scheduled date, it will release Asteriod which may hit the EARTH.
But fortunately, NASA and RUSSIA will launch a space shuttle equiped with NUCLEAR WEAPONS so that they can prevent that danger.
" As we know that, this incident will happen, but there is nothing to worry about. The world will end, but not in 2012. We still have several years to stay over here. We had researched everything and planned the cure of bad activities going to be happen."