From the DailyGalaxy:
It's official: the wingnut segment of American society is now so ignorant rocket scientists have to interrupt exploring the universe to tell them to pack it in. NASA's "Ask an astrobiologist" expert has been inundated with inquiries about the world ending in 2012, forcing Presidential-award-winning scientist Dr David Morrison to write an article explaining how "Hollywood sometimes makes things up."
The doomsday theories are as numerous as they are idiotic, i.e. astoundingly, but three main contenders dominate. The first is the idea that the Mayan calendar ends in 2012. First, no it doesn't - there's just a synchronization of a few of the many calendars they used for various religious, agricultural and social functions. Second, this coincidence of calendars did reset the numbers they used to describe the cycles, but it's about as apocalyptic as ending your Dilbert office calendar - the universe doesn't explode on Dec 31st every year either.
The second is the stunningly stupid concept of a conspiracy theory, the idea that not only has the government somehow suppressed knowledge of an extinction-level event, but that it's Hollywood - an organization which released "Vin Diesel in a car" on no less than four separate occasions - who broke the impenetrable web of secrecy and have decided the best use of knowledge of impending doom is to give John Cusack two and half hours of screentime.
The third is even dumber, if you can process that concept. Some say that a secret shadow planet is on a collision course with Earth, and while we don't want to prejudice you against the theory, it's the planet "Nibiru" as predicted by a woman who claims aliens from Zeta Reticuli had the technology to implant a receiver in her brain and believe the best way to warn Earth is a single screaming woman with a website which would embarrass GeoCities. And "Nibiru" comes from "We were made by ancient astronauts" fan-fiction writer Zecharia Sitchin. And even he says the 2012 theory is bullshit.
We are not even counting the usual Nostradamus bullshit as a legitimate bullshit theory...