As you may be well-informed at this point, the Mayan calendar ends on Dec. 21, 2012, leading to many predictions that the world will collapse just a few hours from now.

Not so fast, say scientists at NASA: The federal agency is so certain that our world will not end that they have already released a video, dated Dec. 22, explaining why the world did not end on the day prior. 

NASA's John Carlson, who directs NASA's Center for Archeoastronomy, has been looking at the 2012 theory for about 34 years. He explains how we misread the Mayan calendar, arguing that it did not actually end on Dec. 21.

Relatedly, NASA scientists have huddled on the issue and found there are "no known asteroids or comets on collision course with earth."

For more from NASA, read this Answer Sheet post.