Ahead of December 21, which marks the conclusion of the 5,125-year “Long Count” Mayan calendar, panic buying of candles and essentials has been reported in China and Russia, along with an explosion in sales of survival shelters in America. In France believers were preparing to converge on a mountain where they believe aliens will rescue them. Doomsday scenarios suggest that the date marks the end of the world or a similar catastrophe. They include the arrival of the next solar maximum, an interaction between Earth and the black hole at the center of the galaxy,or Earth’s collision with a planet called Nibiru.