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Embrace the Darkness: Today Is the Shortest Day of the Year

It has to do with Earth's tilt in relation to the sun, not its distance.

Today is winter solstice, the shortest day of the year.

That means today has fewer daylight hours than any other day. But what actually causes winter solstice? This YouTube video by AccuWeather explains that winter solstice is caused not by the Earth's distance from the sun, but by its tilt.

Our planet is tilted on its axis by 23.5 degrees. So during this time of year, as it travels around the sun, the Northern Hemisphere is tilted away from the sun and receives less sunlight. That's why those of us in New York have shorter days. The Southern Hemisphere, however, is tilted toward the sun, hence why places like Australia are experiencing summer right now.

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Depending on how far you are from the equator, the solstice will be more or less intense. For instance, the North Pole will get 24 hours of darkness on the winter solstice, while on the same day, the South Pole will get 24 hours of daylight on its summer solstice.

While we understand the solstice from the viewpoint of outer space—the Earth's tilt toward or away from the sun—you can notice it down on Earth, too. Aside from the late dawns and early sunsets around the time of winter solstice, the shadows around noontime will be longer in the winter, when the day is almost done, and shorter in the summer, when there's still several hours of sunlight left.

However, just because it's the solstice doesn't mean it's the earliest sunset of the year, or the latest sunrise—depending on where you live. The earliest sunset for mid-northern latitudes comes in early December, whereas for far northern latitudes, it comes in mid-December. By the arctic circle, the earliest sunset and the winter solstice happen on or around the same day. And moreover, the latest sunrise, if you live at a mid-northern latitude, happens in early January.

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