Winter is coming. On Tuesday, December 21, the winter solstice will officially begin in the Northern hemisphere as the region will experience longer nights and shorter days. Meanwhile, the Southern hemisphere will experience longer days and shorter nights than usual.

That means no matter where in the world, everyone will witness the sun reaching its southernmost point in the sky, which signals a seasonal change.

 2021 December Solstice Will Be on the 21st, Marking the Start of Winter: What Happens During This Time?
(Photo : Pixabay/Kanenori)
2021 December Solstice Will Be on the 21st, Marking the Start of Winter: What Happens During This Time?

Winter Solstice 2021: Catch the Season Change in Chicago

According to EarthSky, the winter solstice of the Northern hemisphere this year falls on December 21 at 10:59 AM ET (December 21 at 3:59 UT). At the same time, it marks the unofficial beginning of summer in the south of the Equator. Generally, solstice starts at the same time around the world, although local times may vary based on time zones.

As the sun sets on Tuesday, residents in Chicago can witness this changing of seasons at a location that is specifically designed for the moment. Local news outlet WTTW reported that the event is best seen from the steel ring atop the Exelon Observatory at the western edge of the 606 Bloomingdale Trail that is placed precisely to frame sunsets during the summer and winter solstices, and the vernal and autumnal equinoxes.

Joe Guzman, also known as the Chicago Astronomer, will be hosting a public observation session starting at 3 p.m. to 5 p.m. on Tuesday to celebrate the winter solstice and to treat people to the beautiful view of the sunset.

ALSO READ: Aphelion 2021: What to Expect When Earth Is at Its Furthest from the Sun

Shorter Days and Longer Nights

According to NBC Chicago, residents will see the sunlight in just under nine hours and 11 minutes as the sun will only rise just after 7:13 a.m. and will set after 4:24 p.m. CST. The following days will follow the same pattern in which days will be shorter and nights will be longer.

The winter solstice is known to be the shortest day of the year. Although, the National Oceanic and Atmospheric Administration (NOAA) said that the earliest sunset has already happened on December 8. During the winter solstice, the Northern hemisphere will experience days shorter than 12 hours, while the Southern hemisphere will have longer than 12 hours of daylight.

How Does the Solstice Happen?

Ancient human civilizations have noticed that the path of the Sun across the sky, the amount of daylight, and the location of the sunrise and sunset all change in a regular way throughout the year as evident on monuments, like the Stonehenge, and Machu Picchu that follow the Sun's progress every year.

Today, modern humans know that a solstice is an astronomical event caused by the tilting of Earth's axis at 23 1/2 degrees and its orbital motion around the Sun. The tilt causes the two hemispheres to trad places in receiving sunlight and warmth that causes the winter and summer seasons or the noticeable seasonal shift.

RELATED ARTICLE: 'Full Cold Moon' Will Rise in December to Illuminate Canada's Longest, Darkest Nights of the Year

Check out more news and information on Winter Solstice in Science Times.