The Griffith Observatory in Los Angeles reports that every 18.6 years, our moon reaches the extremes of its orbit around the Earth. "We observe this as the moon rises and sets at its most northerly and southerly positions on the horizon," the Observatory said in a statement. On December 15, we will observe the Moon rising as far to the north as it ever does, the observatory said. This happens during what's known as the "major lunar standstill."