Winter Solstice is an astronomical phenomenon occurring in December every year when Sun's elevation with respect to Earth reaches its lowest value (-25.5 degrees). It is accompanied by the longest day on South Pole and the longest night on North Pole of Earth. In 2013, it occurs at 17:11 UTC on December 21. For the Northern Hemisphere, at the moment of winter solstice, the sun is at its greatest height as observed from the South Pole. Similarly, for the Southern Hemisphere, at the moment of … [Read more...]