Saturday is the winter solstice and 2024’s shortest day. Here’s what you need to know about the official start of winter.

Winter Solstice 2024, the shortest day of the year, will take place on Saturday 21 December in the northern hemisphere. The celestial event marks the first day of winter, astronomically.

What is winter solstice?

The winter solstice is the day each year that has the shortest period of daylight between sunrise and sunset, and therefore the longest night. It occurs when the sun is directly above the Tropic of Capricorn, a latitude that circles the globe south of the equator, National Weather Service explains.

The further north you are, the shorter the day becomes, and in the Arctic Circle the sun does not rise at all.

How is the day of winter solstice determined?

The winter solstice occurs due to the tilt of the Earth as it rotates around the Sun.

As the northern hemisphere tilts away from the sun, the nights last longer. The longest night occurs at the solstice because the hemisphere is farthest from the sun. It happens every year on December 21 or 22.

This year it falls on December 21 at 4:21 a.m. ETto be precise.

At the summer solstice, when the northern slope is closest to the sun, we have the longest day, usually June 20 or 21.

The solstice is not always exactly on the 21st each year because the earth’s rotation around the sun is 365.25 days, instead of 365 straight.

Will the days start getting longer after the winter solstice?

Yes. Every day after the solstice we get one more minute of sunlight. That doesn’t sound like much, but after just two months, or about 60 days, we’ll see about an hour more sunlight.

When will winter officially end in 2025?

The meteorological winter ends on March 20, 2025. After that, spring lasts until June 20, when the summer solstice comes.

How is the winter solstice celebrated around the world?

Nations and cultures around the world have celebrated solstice since ancient times with varying rituals and traditions. The influence of these solstice traditions can still be seen in our celebration of holidays such as Christmas and Hanukkah, Britannica notes.

The ancient Roman Saturnalia festival celebrated the end of the planting season and has close ties to modern day Christmas. It honored Saturn, the god of harvest and agriculture. The multi-day affair had plenty of food, games and parties. Gifts were given to children and the poor, and slaves were allowed to stop working.

Gatherings are held every year at Stonehengea monumental circle of massive stones in England dating back some 5,000 years. The origins of Stonehenge are shrouded in mystery, but it was built to align with the sun solstice days.

The Hopi, a Native American tribe in the northern Arizona area, celebrate the winter solstice with dancing, purification, and sometimes gift-giving. A sacred ritual known as Soy ceremony marks the annual milestone.

In Peru, people honor the return of the sun god at the winter solstice. The ancient tradition would be to hold sacrificial ceremonies, but today people hold fake sacrifices to celebrate. Because Peru is in the southern hemisphere, their winter solstice occurs in June, when the northern hemisphere marks its summer solstice.

Scandinavia celebrates St. Lucia’s Day, a festival of lights.

The “arrival of winter” or Dong Zhi is a Chinese festival where the family gathers to celebrate the year so far. Traditional foods include tang yuan, sweet rice balls with black sesame filling. It is believed to have its origins in post-harvest celebrations.

Scientists stationed in Antarctica even have their own traditions, which may include a icy dives into the polar waters. They celebrate “Midwinter” with feasts, movies and sometimes homemade gifts.