This Wednesday, Dec. 21, winter solstice will occur at exactly 5:44 a.m. EST in the Northern Hemisphere.

Winter solstice, according to Accu Weather "marks the shortest day of the year in terms of hours of daylight." It happens annually when the Earth is tilted 23.5 degrees on its axis or as Telegraph described it, "the North Pole is tilted furthest - 23.5 degrees - away from the Sun, delivering the fewest hours of sunlight of the year." During this time of the year, the Northern and Southern Hemispheres exchange places in receiving the sun's light and warmth.

The solstice also indicates the sun is directly over the Tropic of Capricorn. This phenomenon brings the shorter days and longer nights in a year.

Accu Weather reported that Professor Anthony Aveni of Colgate University stated that during the ancient times, people wonder if the sun would ever come back and had to figure out what to do to calm the gods down. The Greeks made offerings to Apollo, the Incas to Inti, the son god, and the Mayans to Kinich Ahau. The Romans on the other hand celebrated solstice by honoring the God Saturn, an agricultural deity.

When Christianity arrived, the ancient solstice celebration evolved into Christmas. Aveni said that Jesus Christ was not actually born in December but it was changed to fit the season's celebration.

The winter solstice's counterpart in the Southern Hemisphere is the summer solstice which is known as the longest day of the year.

Though the winter solstice is not expected to always land on December 21st , it will surely occur every year. It can happen on the 20th, 21st, 22nd, or 23rd of December. However, solstice on December 20 or 23 is rare. The last recorded solstice that occurred on December 23 was in 1903 and is not expected to happen again until 2303.