What is Winter Solstice?

Winter solstice is the shortest day of the year in the Northern Hemisphere and marks the official beginning of winter. The sun is at its lowest in our sky because the North Pole of our tilted planet is pointing away from it.

In 2007, the solstice occured at 1:08 a.m. ET Saturday, Dec. 22.

If you're already sick of winter, look at the solstice this way: The days are now getting longer. In six months, Earth will be on the other side of the sun and residents of the Northern Hemisphere will enjoy the longest day of the year.

Check out this amazing series of photographs that reveals the sun's shifting position in our sky throughout the year.

• What Causes Earth's Seasons?
• Planet Earth: A Year of Pictures
• When Your Winter Begins