Well, it's official - The world did not end today! But amongst all the hoopla surrounding the rumored demise, the one significant event that you may have missed is that today also happens to be the first day of winter for people living in the Northern Hemisphere. Of course, the opposite is true for those living in the Southern Hemisphere who, are celebrating their first day of summer.

The primary reason for the different seasons in the two hemispheres is that as the Earth rotates around the sun, it also rotates around its own axis. However, this rotation is not straight, but tilted at an angle of 23.5 degrees, causing there to be less light delivered to the Northern Hemisphere and more to the Southern Hemisphere at this particular time. The solstices occur when the sun is the greatest distance from Equator, the imaginary line that divides Earth into the two hemispheres.

While we know the scientific reason behind the winter solstice today, for ancient cultures this day marked the turning point of the cold dark winters and the fear that the energy-giving sun was leaving them. That's because after this date, the days started to become longer again, and while many months of winter still remained, people knew that the sun would be back.

They therefore not only performed elaborate ceremonies during this time, but also, built some of their finest structures, which included tombs,temples, cairns and other sacred observatories.

One of the most famous examples of this is Stonehenge. Located in Wiltshire, England, this pre-historic burial site is believed to have been constructed to celebrate winter solstice. Hundreds of people still gather here each year, to celebrate a pagan tradition called Yule, one of the oldest known solstice-related events.

Also famous for its winter solstice celebrations is Newgrange in Boyne Valley, Ireland. The 5,000 year-old giant stone structure that historians believe must have taken 300 men about 20 years to build, is designed to receive a shaft of light into its central chamber at the dawn of winter solstice. The light in turn, illuminates incredibly intricate carvings. The whole event that lasts for about 17 minutes is so popular, that viewing tickets are distributed via lottery. This year however, the 24 people fortunate enough to win the lottery had to settle for just a sliver of sunlight thanks to the heavy cloud cover that obscured the sun. But, it was still an experience of a lifetime - One they will never forget.

In the USA, many cities have started their own winter solstice traditions. In San Francisco, California, revelers celebrate the day with a bonfire at the city's Ocean Beach. The residents of Anchorage, Alaska who will experience their longest night of the year (18 hours and 33 minutes) have planned a number of activities ranging from festivals to even a dance, to bring back the sun!

Do you have a favorite winter solstice tradition in your town or with your family? If so, be sure to share it with all of us, by adding your comments below.

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