What is the winter solstice? What to know about the shortest day of the year

Although temperatures have been dropping for weeks, winter doesn’t officially begin until Saturday.

Although temperatures have been dropping for weeks, winter doesn’t officially begin until Saturday.

Here’s what to know about the winter solstice, the astronomical start to the snowy season and the shortest day of the year.

The winter solstice marks the beginning of astronomical winter. It’s different from the beginning of the meteorological winter, which is based on our 12-month calendar.

To answer this question more completely, let’s go back to middle school science class for a minute. The Earth rotates in two primary ways: first, it moves in a big circle around the sun; second, it spins around an axis like a top, creating day and night. That axis is tilted on a slight angle, causing the Northern and Southern hemispheres to receive different amounts of sunlight at different times of the year.

While we tend to think about the winter solstice as a day-long event, the term actually refers to a precise moment at which one half of the Earth — either the top or the bottom — is tilted the furthest away from the sun, resulting in the fewest hours of sunlight of the year for that half of the hemisphere.

https://www.nbcnews.com/science/science-news/what-is-winter-solstice-rcna185080

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