It's the end of the world as we know it. Again. This time it's the Mayan Apocalypse, which could supposedly see the planet Nibiru emerge from its hiding place behind the sun to crash into Earth on Dec. 21. If you're feeling nervous, take a look back at six other doomsday predictions from years past, and take comfort in knowing that no such prediction has ever come to pass. At least not yet.

The Rapture, May 2011
What was predicted: Harold Camping, an 89-year-old Christian fundamentalist and fringe radio host, predicted that 1994 was the year the Rapture would begin. When that didn't happen, he concluded that he must have messed up his numbers, which were based on decoded messages in the Bible. After some recalculation, Camping announced that the world would actually end on May 21, 2011. Thousands of his followers left their lives behind to help spread word of the coming apocalypse.

What actually happened: On May 22, the world still stood, and Camping was "flabbergasted." His followers, many of whom had drained their savings to promote the message, reacted with anger and confusion. But Camping quickly reassured them that the real end of the world was coming on Oct. 21, 2011. In case you're wondering, that didn't happen, either. 

Y2K, 2000
What was predicted: Chaos, widespread panic, and a shortage of food and goods — all because of a little computer bug. In the years leading up to the millennium, computer programmers used only two digits to represent years. It was theorized that when the clocks struck 12:00 a.m. on January 1, 2000, the machines would not be able to read the year "00." The Y2K panic was born, and billions of dollars were spent fixing the original source code in older computers. By 1998, 34 percent of Americans anticipated the Y2K bug would cause major problems, and the Independent newspaper even warned that the glitch could spark a nuclear war. 

What actually happened: Midnight struck with no major outages. A few glitches were reported, but for the most part "1999 passed into history with barely a whimper." Experts remain divided over whether Y2K was a legitimate threat or an exercise in mass paranoia.

The Jupiter Effect, March 1982
What was predicted: In 1974, John Gribbin and Stephen Plagemann wrote a best-selling book called The Jupiter Effect. In it, they argued that the planets of the solar system would align in March 1982, triggering massive natural disasters on Earth, including an earthquake on the San Andreas Fault that would wipe out Los Angeles. Nervous residents panicked, and many considered selling their homes and leaving L.A. 
What actually happened: March came and went peacefully. One year later, the two authors released The Jupiter Effect Reconsidered, which also became a bestseller.   

Halley's Comet, 1910
What was predicted: When Halley's Comet reappeared in 1910, the Chicago Yerkes Observatory made the poorly calculated decision to announce that it had detected a poisonous gas in the comet's tail. The New York Times added fuel to the fire by quoting a French astronomer as saying this gas "would impregnate that atmosphere and possibly snuff out all life on the planet." Panic ensued, gas masks were purchased, and people began loading up on "comet pills," which promised to counter the effects of the noxious gas. In an attempt to keep the fumes at bay, homeowners placed pieces of paper over their locks. 
What actually happened: The planet remained undisturbed. Once the comet had passed, The Chicago Tribune announced to readers, "We're still here."

The Great Flood, 1524
What was predicted: In 1499, German-born astronomer Johannes Stoeffler predicted that the world would be engulfed in a massive flood in February of 1524. The planets would align, he said, in the constellation of Pisces, the sign of the fish, dooming the entire world to a watery death. Because of Stoeffler's position as a well-known astronomer and mathematician, his words weren't taken lightly. German Count von Iggleheim was so determined to survive the coming storm, he built a massive three-story ark. And when it did actually start to rain, panicked crowds stormed the ark and stoned the count to death when he refused to let them in. 
What actually happened: When the rain stopped, Stoeffler insisted that he'd miscalculated (sound familiar?), and that the real flood would come in 1528. Stoeffler died shortly thereafter, in 1531, of the plague. 

Author-mania, 2800 B.C.
What was predicted: It appears that mankind's fear of the apocalypse goes way back. An unearthed clay tablet thought to date back to 2800 B.C. reads, "Our earth is degenerate in these latter days. There are signs that the world is speedily coming to an end." What kinds of signs? Bribery and corruption. Disobedient children. Plus, "Every man wants to write a book, and the end of the world is evidently approaching."
What actually happened: Our understanding of this time period is limited, but we know the human race still thrives, kids are still mouthing off, and basically everyone still aspires to become a renowned author.