With the recent snowstorms that have been blanketing many parts of the country, it may appear that winter has been here for sometime now. Unfortunately, that is not the case. Tomorrow, December 21st, is Winter Solstice, the official start of the season for the residents of the Northern Hemisphere. Of course, the opposite is true for the lucky folks that live in the Southern Hemisphere who will be celebrating the first day of summer.

The reason for the different seasons in the two hemispheres is due to the rotation cycle of earth around the sun and its own axis. As you are probably aware, the latter rotation is tilted at a 23.5° angle. This causes less sunlight to be 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 today we know the scientific reason behind the solstice, for ancient cultures this day marked the turning point of the cold dark winters and the fear that the energy giving sun had abandoned them. That's because after the shortest day of the year, the sun seemed to magically return and remain in the skies for an increasingly longer time, each day. Though many months of winter still remained, people knew that the sun had not abandoned them.

In order to celebrate this phenomenon, many ancient cultures performed elaborate ceremonies during this time and even built some amazing structures. One of the most famous examples of this is Stonehenge in Wiltshire, England, a pre-historic burial site 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 have to be distributed via lottery, each year.

In the USA, many cities have started their own Winter Solstice traditions. In San Francisco,California, revelers will 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 also planned numerous events ranging from sleigh rides in the park, to a spectacular fireworks show.

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.