What You Need to Know About the Upcoming Winter Solstice

The winter solstice is upon us. When can you expect the shortest day of the year and what does the solstice technically mean? Read on for all of the details.

Understanding the Science of the Winter Solstice

The winter solstice is distinguished as being the shortest day of the year as well as the beginning of the astronomical winter season. This year's winter solstice will happen in the Northern Hemisphere on Saturday, December 21 at 4:20 am EST. Note that this is different from the official start of the meteorological winter that starts on December 1 every year.

In addition to featuring the shortest day of the year, the winter solstice is also the longest night of the calendar year. Past this date, the days will incrementally become longer with more sunlight available.

Conversely, the Southern Hemisphere celebrates the summer solstice at the same time. This means that places such as Australia and Brazil experience the longest day of the year and the shortest night at this time.

Why does this happen like clockwork? Scientists explain that the Earth is always slightly tilted on its axis as it moves around the sun. The December solstice is the precise moment that the sun shines right at the Earth's most southern point over the Tropic of Capricorn. During this time, the Northern Hemisphere is tilted away from the light coming from the sun while the Southern Hemisphere is pointed right toward the direct sunlight.

This tilting explains why the Northern Hemisphere does not receive as much light, translating to darker days and colder weather overall. As the Northern Hemisphere is shielded from the light, the Southern Hemisphere is basking in the sun. As such, the beginning of the astronomical summer happens in the Southern Hemisphere at this time.

Term Solstice Has Roots in Latin Language