The 2012 phenomenon comprises a range of eschatological beliefs which posit that cataclysmic or transformative events will occur on December 21 or December 23, 2012, is said to be the end-date of a 5,125-year-long cycle in the Mayan Long Count calendar. These beliefs may derive in part from archaeoastronomical speculation, alternative interpretations of mythology, numerological constructions, or alleged prophecies from extraterrestrial beings.
A New Age interpretation of this transition posits that, during this time, the planet and its inhabitants may undergo a positive physical or spiritual transformation, and that 2012 may mark the beginning of a new era. Conversely, some believe that the 2012 date marks the end of the world or similar catastrophe. Both ideas have been disseminated in numerous books and TV documentaries, and have spread around the world through websites and discussion groups.
Scholars of various stripes have disputed the idea that a catastrophe will happen in 2012, suggesting that predictions of impending doom are found neither in classic Maya accounts nor in contemporary science. Mainstream Mayanist scholars argue that the idea that the Long Count calendar "ends" in 2012 misrepresents Maya history. To the modern Maya, 2012 is largely irrelevant, and classic Maya sources on the subject are scarce and contradictory, suggesting that there was little if any universal agreement among them about what, if anything, the date might mean.
Meanwhile, astronomers and other natural scientists have rejected the apocalyptic forecasts, on the grounds that the anticipated events are precluded by astronomical observations, or are unsubstantiated by the predictions that have been generated from these findings. NASA likens fears about 2012 to those about the Y2K bug in the late 1990s, suggesting that an adequate analysis should stem fears of disaster.