The winter solstice marks the date of the shortest period of daytime light and longest night of the yearMeteorological is the simpler of the two options, as it splits the year into four seasons of three full months each based on the Gregorian calendar, which makes it easier to compare seasonal and monthly statistics.
The astronomical season isn’t quite as straightforward because the first date falls on the date of the winter solstice, which arrives later in the year and can vary slightly from year to year. It can occur on any date between 20 and 23 December, but usually takes place on the 21st of the month.winter solstice
The exact moment of solstice occurs at the minimum point for the Northern Hemisphere, when the Sun is lowest in the sky. Traditional holidays across the world have often focused on the rebirth of nature for this reason, and many of the traditions now associated with Christmas began as observances of the astronomical phenomenon.