1. The world will come to an end on December 21, 2012.
2. That is how New Agers, anticipating a rebirth of consciousness, interpret the Mayan calendar.
3. In reality, December 21 is the date on which the Mayans’ 1,872,000-day “long count” calendar is set to roll over, like the Gregorian year 1000. Remember how the world ended then? Exactly.
4. Baptist preacher William Miller, seeing through the Bible darkly, convinced 50,000 New Englanders that the rapture would happen by March 21, 1844.
5. Happily for Harold Camping, a nonagenarian broadcaster, Miller was mistaken, allowing Camping to announce that the Bible predicted the end of the world on May 21, 2011.
6. In 1806 a British con artist named Mary Bateman inscribed “Christ Is Coming” on eggs and stuffed them back up a chicken’s vent. She charged a penny to witness the feathered prophet. She was later executed for murder.
7. But apocalypses do happen. The biggest mass extinction, or Great Dying, was triggered by a volcanic eruption in Siberia 250 million years ago. Nearly 80 percent of all species were lost.
8. Siberian surface rock was loaded with carbon, resulting in runaway global warming as atmospheric CO2 levels more than doubled.
9. Dinosaurs were unlucky the asteroid that crashed to Earth 65 million years ago vaporized a mother lode of sulfur-rich rock, triggering acid rain and global cooling.
10. Today CO2 levels are the highest they’ve been in 800,000 years. Memo to Washington: It isn’t on account of a volcano or an asteroid.
11. That may change on February 5, 2040, when there’s a 1-in-500 chance that a 460-foot asteroid named 2011 AG5 will hit the planet and spell the end of a major city.
12. NASA reports that about 10,000 other asteroids are within striking distance.
13. Worse than getting hit by a chunk of cosmic debris is passing through a dust cloud of it, which, once in a billion years, could block the sun for a deadly cold 200,000 years.
14. In a few hundred thousand years, WR-104, a star about 8,500 light-years away, could explode and unleash the equivalent of two thousand billion billion billion megatons of TNT. Radiation from that blast would wipe out Earth’s ozone layer, and we’d be fried by the sun.
15. Speaking of the sun, it will expand into a red giant larger than Earth’s orbit in 7.6 billion years. Anything lucky enough to survive the oceans boiling dry will get vaporized by 4,000-degree plasma.
16. Today rumors continue to circulate about a Russian “doomsday machine.” If Russia was nuked, it would automatically launch a retaliatory nuclear strike.
17. If modern society is wiped out, head to Georgia. In Elbert County, you’ll find granite slabs erected in 1980 by an anonymous pious patriot, engraved with instructions for starting over, like “seeking harmony with the infinite.”
18. Easier said than done. Cosmologists tell us the universe could end in a Big Rip about 20 billion years from now, when the dark energy causing everything to race away from us will tear every atom apart.
19. Or there could be a Big Crunch, in which gravity overcomes dark energy, drawing the universe together into a single point of infinite mass.
20. Then again, everything might peacefully keep drifting apart. That would leave plenty of time for random quantum events, like a new Big Bang in 101056 years. That’s a 1 followed by one hundred million trillion trillion trillion trillion zeros—the ultimate long-count calendar.
Johathon Keats, a contributor to Wired, is the author of Virtual Words: Language on the Edge of Science and Technology.