Did you know that Earth has an expiration date? Yes, it's Dec. 21, 2012. That's when life as we know it will end. Who says? The ancient Mayans predicted it, Chinese sages wrote of it and many Christians say it's foretold in the Bible.

Go ahead, Google 2012, search for it on YouTube and learn. Or buy "The Complete Idiot's Guide to 2012," now in bookstores. You could wait for the movie; "2012" will be in theaters this fall.

Meanwhile, look clued-in with a "2012 Doomsday" T-shirt (available in infant and toddler sizes, too). Basically, our days are numbered - to less than 1,300 - because a convergence of factors will result in the destruction of Earth: Extreme solar activity will peak just as Earth's protective magnetic shield is weakening, and there will be an alignment of planets that happens only once every 640,000 years. To top it off, the highly complex and accurate 5,000-year Mayan calendar comes to an abrupt end on winter solstice 2012. It all adds up to bad business for our planet.

"The odds of global destruction are projected at 94 percent," according to the Web site for the Institute for Human Continuity. It's working to ensure the survival of the human race beyond 2012. (More about that later.)

For those rolling their eyes, or maybe rolling in the aisles, harken to the words of science.

"There's no disaster coming," said Lawrence Rudnick, distinguished teaching professor of astronomy at the University of Minnesota, responding to fears of killer solar flares. Scientists aren't discussing 2012.

There's nothing there, Rudnick said. It isn't even interesting. "We have plenty of real issues to worry about on Earth," he said.

It seems "The end is near!" is heard every few years. What is it about the apocalypse that we can't stop worrying about it?

"It's fear of death," said Harvey Sarles, professor of Cultural Studies and Comparative Literature at the University of Minnesota. Doomsday anxiety goes way back. It's a product of Western thought and religious tradition, he said _ basically, the stories of Christianity and Islam and the focus on death and getting back to heaven.

In times of strife or pivotal calendar moments, Armageddon fears gain traction. They're actually very appealing and comforting to some people, Sarles added.

Indeed, cataclysm and destruction predictions fit well with some Christian interpretations of the Bible's Book of Revelation, according to Sarles. The current financial upheaval, natural disasters, flu epidemic - even the disappearance of honeybees - are seen as run-ups to the main 2012 event, according to some Christian Web sites. They see the four horsemen of the apocalypse closing in, and they welcome it. The second coming of Christ is near, they believe, and they'll soon be a pile of clothes on empty shoes after they're Raptured.

But not all 2012 devotees are of the same mind. New Agers, such as author and professor Jose Arguelles, predict that "the end of the world as we know it" means that there will be a universal spiritual awakening. It isn't the end of the world, they say, but the beginning of a new and better one, which is an interpretation closer to what the Mayans believed. From troubled times will rise a new consciousness. Events surrounding 2012 are but the birth pains of a new age, the Age of Aquarius, at last.

Some scoff at the whole 2012 idea and predict a Y2K-style fizzle. Natural calamities and human strife happen all the time, and the Mayan calendar ending has no significance. It's just a calendar, they write in their blogs and Web sites. Like any other calendar, it ran out; time to get a new one.

Meanwhile, there's money to be made before the drop-dead date. There are books to peddle, bunkers to sell and TV shows to produce - ABC's "Wife Swap" is looking for families that are preparing for 2012 for their "Wife Swap 2012 Special" - and a host of movies to promote. In a slick marketing move, Sony Pictures created a very realistic organization and Web site - the Institute for Human Continuity (www.instituteforhumancontinuity.org) - for its movie "2012."

It's fake, but you wouldn't know it by the Web site. Besides sophisticated interactive disaster scenarios, it tells visitors that the institute has been working 30 years on preparation strategies and is now running a random lottery "to give all humans an equal shot at surviving." Sign up now, the site urges, and since it's one ticket per person, get the family to sign up, too. (The lottery is probably for free movie tickets.)

If you still believe that maybe this time it's different, that 2012 really is the end, don't be tempted to run up the credit cards or spend your 401(k) thinking you'll be expiring instead of retiring. A safer bet for winter solstice 2012 is that autumn will end, winter will start and it'll be cold in Minnesota.

Distributed by McClatchy-Tribune Information Services.