Today, Saturday the 21st of December, is the winter solstice in the northern hemisphere. When viewed from northern latitudes, the Sun will make its lowest arc through the sky along the southern horizon. The day of the winter Solstice has the shortest length of time between sunrise and sunset and hence the fewest hours of daylight.
The winter solstice happens annually when the sun reaches its most southerly declination of -23.5 degrees. In other words, it is when the North Pole is tilted 23.5 degrees away from the sun. On the winter solstice all places above a latitude of 66.5 degrees north (Arctic Polar Circle) are now in darkness, while locations below a latitude of 66.5 degrees south (Antarctic Polar Circle) receive 24 hours of daylight.
The exact moment of the northern winter solstice is 17:11 pm GMT (12:11 pm EST), after this point the Sun will commence its journey back up North and the days will get gradually longer.
This striking composite image follows the Sun’s path through the December Solstice day of 2005 in a beautiful blue sky, looking down the Tyrrhenian Sea coast from Santa Severa toward Fiumicino, Italy. The view covers about 115 degrees in 43 separate, well-planned exposures from sunrise to sunset.