Winter solstice, the shortest day of the year and the official first day of winter, is on Thursday, December 21, this year (well, for the vast bulk of the Americas anyway). How the solstices — along with the spring andfall equinoxes— work has fascinated people for thousands of years....
The winter solstice marks the shortest day of the year and the longest night in the Northern Hemisphere, when the sun appears at its most southerly position, directly overhead at the Tropic of Capricorn. The situation is the reverse in the Southern Hemisphere, where only about 10% of the wo...