If doomsday soothsayers are to be believed, the world has less than a year to exist because everything's going to end on December 21, 2012.

There are many theories floating around the Internet about how the world will end next year. The most popular being the Mayan prediction from 1,300 years ago. According to the Mayan Long Count Calendar, December 21, 2012 will mark the end of a b'ak'tun, a 144,000-day cycle. The b'ak'tun that will end on December 21 is the 13th cycle, a number that started all the apocalypse predictions. The truth is that the Mayan never predicted any cataclysms. The end of the Long Count calendar was just a measure of time for the ancient Mayan. It was Franciscan missionaries who actually attached the end of the world myth to the end of the 13th b'ak'tun.

Another doomsday scenario for 2012 is that a supervolcano will erupt to kill off all life on the planet. Supervolcanoes are capable of spewing out thousands of times more magma and ash than regular volcanoes. A supervolcano eruption could wipe out millions of people and blot out the sun with ash. The largest supervolcano explosion happened 74,000 years ago in Sumatra. The explosion of Mount Toba released 700 cubic miles of magma and a thick layer of ash that covered all of South Asia. There are a dozen supervolcanoes today, most of them lying at the bottom of the sea but researchers agree that chances of a super-eruption happening next year are miniscule. Geologists think there is a super-eruption every 700,000 years or so and there is no sign that a super-eruption is going to happen anytime soon.

Most popular doomsday scenarios involve astronomical phenomenon. The theories are getting so prevalent that NASA has been spending a lot of time debunking them and assuring the public that a rogue planet, a black hole and a supernova isn't going to smash our planet into smithereens. One theory has a mysterious Planet X or Nibiru crashing into Earth in 2012. That's one theory that was easily disproven because Nibiru doesn't exist. NASA would have seen that planet years ago. Likewise there is absolutely no chance that a cosmic alignment between the Earth, the Sun, the Milky Way's black hole and the dark cosmic dust will send the Earth into the black hole. The galactic center is 165 quadrillion miles from the Milky Way's black hole much too far for Earth to travel.

As for a supernova exploding next December? Not a chance. Francis Reddy of NASA's Goddard Spaceflight Center said on Friday that there is no threatening star close enough to hurt Earth.

"Astronomers estimate that, on average, about one or two supernovae explode each century in our galaxy," says Reddy. "But for Earth's ozone layer to experience damage from a supernova, the blast must occur less than 50 light-years away."

One doomsday theory that's somehow rooted in science involves our solar system's Sun. Doomsday theorists are saying that a massive solar flare will burn Earth next year.

While it's true that the Sun will experience more solar flares in 2012 to 2013 it doesn't necessarily mean that the Apocalypse is upon us. The Sun naturally goes through 11-year cycles of activity and non-activity. The upcoming maximum peak is expected to occur in 2013 but it doesn't mean that solar storms will mean the end of all life on Earth. Humans should be concerned about solar storms because they can disrupt electronics on the planet but industries can prepare for them and government agencies can predict these storms' coming.

Another doomsday theory is the magnetic pole reversal theory. Believers think that the Earth's magnetic field will switch next year to destroy life on the planet by dropping the magnetic-field barrier and exposing life to dangerous radiation from space. According to NASA the planet has survived magnetic field reversals before without a scratch. The flips happen every 200,000 to 300,000 years and they occur over hundreds of thousands of years not in one year.

In the end doomsday scenarios are just theories. 2012 will come and go and end-of-the-world believers will have to think up new ways the world can end in 2013.