IF you're reading this, it hasn't happened yet. But some time today, according to the ancient Mayan prophecy, the world is going to end.
And while scientists say the apocalypse is not nigh, just in case they're wrong they've come up with a raft of bloody and catastrophic possible scenarios, including dark comets, famine, super-volcanoes, catastrophic climate change and a plague of cancers, the Daily Telegraph reports.
Astrophysicist Professor Jocelyn Bell Burnell, who discovered pulsars, believes the most likely disaster to put doomsday into today's diary is a black comet.
Such an end would match that of the dinosaurs who, after walking the planet for about 165 million years, were killed off when a 10km-wide asteroid or comet slammed into the planet. Homo sapiens have been around for just 200,000 years.
Dark comets have little of the ice and snow of most comets and have a lot more dust, making it much more difficult to spot them as they speed through space.
The collision, except for those near the impact, would unlikely be fatal to the world's population. But it would throw up so much dust that billions of people could expect a slow death.
Huge quantities of dust would bring an "eternal winter" in which the sun would be obscured and crops would fail, leading to mass famine.
Dr Dave Rothery, a vulcanologist, foretells a similar end, but thinks the dust would be spewed into the atmosphere by a super-volcano.
If one erupted, around 400cu km of molten rock and debris would be blasted into the sky, much of it remaining in the atmosphere as volcanic dust.
"It would put so much ash and sulphur dioxide into the atmosphere that photosynthesis may break down," he warned. A similar, though less devastating, eruption took place in 1816 when a volcano in Indonesia put so much dust into the atmosphere it became known as "the year of no summer".
The favourite doomsday scenario of Bryan Lovell, former president of London's Geological Society, is a vast escape of methane gas caused by an undersea landslide.
Methane is a greenhouse gas, but it is about 20 times more powerful in warming the world than carbon dioxide.
Dr Lovell said a huge release of sub-sea methane would lead to "catastrophic climate change not too many Fridays from now".
The doomsday prophecy is based on an ancient calendar from the Mayan civilisation in what is now Guatemala in Central America. The calendar lasts for more than 5000 years but comes to an end today, which has prompted fears it forecasts the end of the world.
It is not just scientists putting forward theories as to how the world will end. Among the favourites is that a rogue planet, Nibiru, which has long been inhabiting the solar system beyond Pluto, is now on a collision course with Earth. Scientists have dismissed the theory as ridiculous because if such a large object was heading this way it would have been spotted.
Other favourite doomsday scenarios include a vast solar storm which will flare out from the sun and engulf Earth, a rogue black hole that will swallow the Earth, or a quirk of galactic alignments that triggers a disastrous reverse of the Earth's magnetic field.
Scepticism on the part of experts, however, hasn't dimmed some people's determination to take action - mostly in the form of parties.
While there's a $1000-a-head party planned for Moscow and a barge party on London's Thames, The Canteen at Bondi is charging $60 for its party which includes a complimentary armageddon cocktail. The Shelbourne Hotel will host an end of the world party from 9pm.
Read more at the Daily Telegraph.
