Winter Solstice is a major event of the year marking the official start of winter in the Northern Hemisphere. This is the shortest day and longest night of the year, as the North Pole is tilted farthest away from the Sun. This year, it falls on Saturday, December 21, at 4:21 a.m. EST in the Northern Hemisphere. The Earth’s tilt of approximately 23.5 degrees on its axis is the primary reason for the occurrence of the winter solstice and the changing seasons.
What happens during Winter Solstice?Â
As our planet orbits the sun, the tilt causes the Northern and Southern Hemispheres to receive varying amounts of sunlight throughout the year. This results in contrasting seasonal differences between the two hemispheres. During the Northern Hemisphere’s winter, the region receives limited daylight, while the Southern Hemisphere enjoys summer. Winter Solstice occurs when the North Pole is tilted farthest away from the sun, resulting in the least amount of daylight and the longest night of the year.
The winter solstice occurs on specific dates in each hemisphere. In the Northern Hemisphere, it falls on either December 21 or December 22 every year. In the Southern Hemisphere, the winter solstice takes place on either June 20 or June 21 annually. The date of the winter solstice varies slightly from year to year due to the Earth’s elliptical orbit around the sun. The Gregorian calendar’s 365-day cycle, with an extra leap day added every four years, doesn’t perfectly align with the Earth’s 365.25-day orbit, as per NASA.Â
Significance of Winter Solstice
This phenomenon holds profound cultural, historical, and astronomical significance. For ages, people across the world have recognised this important astronomical occurrence and celebrated the subsequent “return” of the Sun in a variety of different ways. Some ancient monuments, like Stonehenge, are even aligned with the sunrise or sunset on the winter solstice.
In addition to its cultural significance, the winter solstice also marks a turning point in the Earth’s journey around the sun. After the shortest day, the days begin to get longer, and the sun’s path across the sky changes. This shift is almost imperceptible, which is why the term “solstice” comes from the Latin phrase “sun stands still”.
How to observe the Winter Solstice
A good way to mark the event is to watch the sun rise and set on the day of solstice. The most popular annual tradition sees people gather at Stonehenge to watch the sunrise. Another way is to simply go outside after dark, and do some stargazing.
