Asteroid/Meteor/Comet - ancient, advanced civilizations have one distinct advantage over us - they may have observed the skies for longer, and may have spotted an orbit that will culminate in a collision with Earth in 2012. This is easily the most predictable disaster for 2012. With recent discussion of "dark comets", we have become aware of the possibility of our planet being struck with little or no warning.
Coronal Mass Ejection (CME) from our Sun - a CME was behind the solar storm of 1859. It occurred in September of that year, causing the failure of telegraph systems across North America and Europe. Accompanying the storm were auroras that are normally only seen in the Arctic and Antarctic, but were visible as far south as the Caribbean. Typically we would expect a storm of 1859's magnitude cause power blackouts and wreck satellites. But do we really know how big they can get? In 2009 NASA told us to be wary of solar storms, and warned of the dangers to America's ancient overloaded power grid. Being without power for a few months, in the developed world, is a lot more serious than most people realize.
Magnetic Pole Shift - pole reversals have been happening on average once every 400,000 years, with the most recent one being 730,000 years ago - so we are well overdue. Not only do we not know much about reversals, scientists are still unsure about how our magnetic field is generated. Long thought to be a by-product of the movements of liquid iron in our planet's core, recent studies are suggesting that our salty oceans might be the cause. Scientists suggest a geomagnetic reversal takes thousands of years and does no harm. They are wrong - it could just as easily happen overnight. No mechanism is known for the cause of the magnetic poles swapping places. Our magnetic field is known to be rapidly declining (10% in the last 150 years), and the magnetic North pole is moving around at an accelerating pace - it has been predicted it will move from Canada to Siberia in the next 50 years. These changes could be indicating an imminent reversal.
Explosion from the black hole at the center of our galaxy - in 1983 Dr Paul LaViolette described the dangers of a Galactic core explosion. He explained that it would generate a cosmic ray superwave, and it would be signalled by a gamma ray burst (see below). He also warned us that a gravity wave might travel ahead of the superwave. If seems likely that the 2004 tsunami was caused by a gravity wave, because the accompanying GRB arrived just 21 hours later, and was the brightest ever observed, 100 times brighter than any other seen in recorded history. This gravity wave did not come from our galactic center, but if it had, perhaps the effects would have been much worse.
Religious Apocalypse - or rapture, or "judgement day". Most religions predict such a day. Conspiracy theorists suggest that many world leaders have apocalyptic beliefs, and may even be attempting to cause Biblical prophecy to be fulfilled in 2012 via their actions. If it helps, the Bible says “But of that day and hour knoweth no one, not even the angels of heaven, neither the Son, but the Father only.” But then again, maybe God changed his mind since the Bible was written, and told some people the date of the apocalypse? Maybe he told the ancient Mayans? Possibilities could be argued ad infinitum.
Gamma Ray Burst (GRB) - a 2004 study told us that a GRB from a distance of just one kiloparsec could destroy half of Earth's ozone layer. It suggests that historical mass extinctions may have been caused by GRBs. NASA explains how "gamma-ray radiation from a relatively nearby star explosion, hitting the Earth for only ten seconds, could deplete up to half of the atmosphere's protective ozone layer. Recovery could take at least five years. With the ozone layer damaged, ultraviolet radiation from the Sun could kill much of the life on land and near the surface of oceans and lakes, and disrupt the food chain."
Crustal Displacement - a physical pole shift. The mechanism is not understood, and most theories are just wild guesses. However it seems quite likely we had one 12,000 years ago, and what goes around, comes around. Charles Hapgood provided substantial evidence for a pole shift at that time, and Allan and Delair have added to it in their book Cataclysm!: Compelling Evidence of a Cosmic Catastrophe in 9500 B.C. Take into account that Albert Einstein endorsed Hapgood's ideas, and we have something to worry about.
Cosmic Rays - scientists have yet to work out where most high-energy cosmic rays come from. Either an increase striking our atmosphere, or a weakening of our shields, will let in more cosmic rays. They are already zipping through your body every second, and they could end up being our silent killers. As one example of their danger, airlines do not let pregnant women work on their inter-continental routes, because of the increased exposure to cosmic rays at those heights.
Nuclear War / WW3 / Biological War - although the Cold War is over, and fewer bunkers are being built, the threat is still very real. Tensions between the Koreas, and India & Pakistan are worrisome, as are the huge bunkers that the Russians have built. The Yamantau complex is large enough to protect 60,000 people!
Supervolcano - these are real, they have caused great catastrophes in the past, and we have no idea when the next eruption will be. Some believe Yellowstone could explode again soon, as it has been exhibiting signs of unrest, with earthquake swarms, ground deformation and considerable heat and gas emissions. It it did erupt, expect half of the USA to be wiped out, and major variations in global climate for many years
The Nibiru collision is a supposed disastrous encounter between the earth and a large planetary object (either a collision or a near-miss) which certain groups believe will take place in the early 21st century. Believers in this doomsday event usually refer to this object as Planet X or Nibiru. The idea that a planet-sized object could possibly collide with or pass by Earth in the near future
