The Mayan Calendar ends on December 21st, 2012. Why does the calendar end? What is going to happen on that date? How is that event going to affect the 7 billion of us living on earth?The Mayan Calendar ends on December 21st, 2012. Why does the calendar end? What is going to happen on that date? How is that event going to affect the 7 billion of us living on earth?The Mayan Calendar ends on December 21st, 2012. Why does the calendar end? What is going to happen on that date? How is that event going to affect the 7 billion of us living on earth?