
Jody Victor : The Shortest Day Of The Year
by
Jody Victor
on Thu 21 Dec 2006 12:46 PM EST
Jody Victor : I'm sure you have noticed the days getting shorter - having to drive home from work in the dark. This year December 22 is the Northern Hemisphere's winter solstice, the shortest day - and longest night - of the year.
The length of days changes throughout the year. In the summer, the sun often sets after 9 p.m. In winter, it may already be dark as you head home from school or work. Day length varies because of the Earth's tilt.
The Earth travels around the sun. But the Earth does not orbit with the North Pole at the top and the South Pole at the bottom. Instead, the Earth is tilted slightly. Because the Earth is tilted, different parts of the Earth face the sun at different times of year.
The Northern Hemisphere's winter solstice occurs when that hemisphere is tilted the farthest away from the sun. This happens every year between December 21 and 23. But what about the Southern Hemisphere? Here's where the winter solstice gets complicated.
The Southern Hemisphere has its summer solstice when the Northern Hemisphere has its winter solstice. That's because in December, the Southern Hemisphere is tilted toweard the sun. When it's winter in the Northern Hemisphere, it's summer in the Southern Hemisphere.
The winter solstice marks the official first day of winter. People have celebrated the day around the world and throughout history.
Ancient Egyptians held ceremonies during the solstice. And more than 4,000 years ago in Ireland, people built a tomb designed to let in light only during the solstice.
Native Americans, such as the Hopi and Zuni Indians, celebrate the day. And people have honored the solstice in China, Japan, and Taiwan too.
Even Hanukkah and Christmas are related to the winter solstice. Hannukkah always begins three days before the new moon that is closest to the winter solstice. The new moon is when the dark side of the moon is facing Earth.
Ancient Rome had a major festival in honor of Saturn, their god of farming, on the winter solstice. The solstice occurred around December 25 on the Roman calendar. About 1,600 years ago, Pope Julius I of the Catholic Church decided that Christmas should be celebrated on December 25, so that a Christian holiday would replace the ancient Roman one.(So, if you ever wondered how Christmas came to be celebrated exactly on December 25 - that's your answer!)
If short days and long nights give you the blues, don't worry, after the winter solstice, each day gets a little longer. Now that's something to celebrate!
Jody Victor