As it turns out, the end is not near after all. While you can't keep a good doomsday rumor down, NASA Senior Scientist David Morrison is trying to dispel widely circulated rumors that cosmic events will lead to the end of life on Earth, if not outright destroy the planet, on Dec. 21, 2012. Morrison, a planetary astronomer and keeper of NASA's "Ask an Astrobiologist" service, is publishing a rebuttal to many rampant apocalyptic rumors in the journal of the Astronomical Society of the Pacific, partially in response to an increasing number of letters and emails from a public worried that the end is nigh. Morrison specifically addresses the myth that a fictional planet called “Nibiru” will collide with Earth, but also addresses other persistent rumors that solar activity, alignments with the center of our galaxy and other astrological phenomena will wreak havoc on the blue planet and end life here. “Nibiru”, Morrison says, was conjured by Zecharia Sitchin, an author of fictional literature centering on the ancient Mesopotamian civilization of “Sumer”. Sitchin claimed in several books to have found and translated ancient texts that identify the planet “Nibiru”, which orbits the sun every 3,600 years and which will collide with Earth . . . in May 2003. This finding was corroborated by psychic Nancy Lieder who, channeling aliens inhabiting a non-existent planet near the star Zeta Reticuli, learned that Earth is in danger from the planet “Nibiru”. When the May 2003 collision didn't occur, doomsday was rescheduled for December 2012, conveniently concurrent with the end of one of many increments of time known as “Baktuns” on the Mayan calendar. These 394-year periods have come and gone many times since the Mayans made their calendar, much like the months and years on the Gregorian calendar. But even practicing Maya don't believe the world will end on Dec. 21, 2012, when the 13th “Baktun” rolls over. As Morrison notes in his paper, "my desk calendar ends much sooner, on December 31 2009, but I do not interpret this as a prediction of Armageddon." Of course, Morrison also points out, the most compelling reason to believe “Nibiru” won't wipe out the earth in 2012 is that the planet doesn't exist. But try telling that to the man in the tinfoil hat. Then there's the theory of magnetic polar reversal, in which the magnetic polarity of changes. This indeed is a real phenomenon, happening irregularly every 400,000 years on average. But as far as science can tell, this doesn't harm life on earth, nor does it reverse the rotation of the planet, nor is there any reason to believe a reversal is imminent in 2012, as many Web sites would have you believe.