2025年3月11日 · Astronomical winter begins at the winter solstice, which is the shortest day of the year. This means days get longer during winter—very slowly at first, but at ever-larger daily intervals as the March equinox approaches, heralding the start of spring .

The winter solstice is the reversal of the Sun's apparent ebbing in the sky; the daytime stops becoming shorter and begins to lengthen again. In parts of ancient Europe, this was symbolized as the death and rebirth of the Sun, or of a Sun god .

In 2025, the first day of winter is Saturday, December 21. So, what is the winter solstice and why does it happen? Learn all about the shortest day of the year—and tell us what winter means to you!

Winter time is often used to describe the time of year when a country is not on Daylight Saving Time (DST). Similarly, summer time is used to describe the DST-period. Winter clock: The term winter time is used instead of standard time.

During the winter, daytime lasts shorter than 12 hours; during the summer, it lasts longer than 12 hours. Northern winter and southern summer concur, while northern summer and southern winter concur. At the Equator, the daytime period always lasts about 12 hours, regardless of season.

2023年12月21日 · When does the winter solstice happen? The date and time of this astronomical event varies year-to-year, but typically occurs either on the 21st or 22nd of December. The 2023 winter solstice...

2024年12月20日 · Get ready to embrace the darkness during the longest night of the year ‒ the winter solstice. The solstice occurs at the same time everywhere on Earth, this year it happens Dec. 21 at 4:21 a.m....

2024年12月18日 · Winter solstice is the shortest day of year, longest night of the year and the official first day of winter in the Northern Hemisphere. Find out about the science and traditions behind the...

2024年12月17日 · In 2024, the winter solstice happens on Saturday, Dec. 21 at 4:21 a.m. EST in the Northern Hemisphere. But what's the science behind the shortest day and longest night? The winter solstice —...

2024年11月24日 · In the Northern Hemisphere, the winter solstice occurs every year on Dec. 21 or 22. This year, it falls on Dec. 21. The summer solstice is six months later around June 21. …