Wednesday is the first official day of winter.
The winter solstice happens to be the Northern Hemisphere's shortest day and longest night of the calendar year, according to the National Weather Service.
Per the U.S. Naval Observatory, the winter solstice, which occurs on Dec. 21 or 22, will last until March 20, 2023, NWS said.
The NWS said this is because the sun appears right above the Tropic of Capricorn, located 23.5° south of the equator, going through Australia, Chile, southern Brazil, and northern South Africa.
According to the U.S. Naval Observatory, the winter solstice will happen at 4:48 p.m. ET.
CNN reported that that's about six hours later than it was last year.
According to Space.com, people in the Northern Hemisphere will get about 8 hours and 46 minutes of sunshine.
In the Southern Hemisphere, the complete opposite is happening. There it's the longest day of the year and the start of the summer.
Many traditional celebrations on the solstice occurred Wednesday.
In Ireland, people gathered for sunrise at the prehistoric monument Newgrange, which is believed to have been built 5,000 years ago by the Neolithic, the Associated Press reported.
According to the news outlet, it was possibly built so the sun could shine on the ashes of the dead in the tomb, which represents a sign of rebirth.