What happens at the December solstice
Earth’s axis is tilted about 23.4 degrees. In December the South Pole leans most toward the Sun and the North Pole most away from it. At the moment of the solstice, the Sun is directly overhead at noon along the Tropic of Capricorn, at about 23.4 degrees south, a line that crosses Brazil, Namibia, Madagascar and Australia.
North of the equator, the Sun’s noon height is at its lowest of the year. In the south it is at its highest. Like the June solstice, the date takes its name from the way the Sun seems to “stand still” in its north-south drift before reversing.
When it falls
The December solstice falls on December 20, 21, 22 or 23, depending on the year and the time zone. In Coordinated Universal Time it is usually December 21 or 22. It is a single moment, so the local date depends on where you are when it happens. The seasons page gives the exact time for your zone.
Shortest day in the north, longest in the south
| Approximate latitude | Daylight at the December solstice |
|---|---|
| 60° N (Oslo, Helsinki) | About 5 hours 50 minutes |
| 50° N (Prague, Vancouver area) | About 8 hours |
| 40° N (Madrid, New York) | About 9 hours 20 minutes |
| Equator (0°) | About 12 hours 7 minutes |
| 34° S (Sydney, Cape Town) | About 14 hours 25 minutes |
Values are rounded. You can check the exact figures for your location on the sunrise and sunset page.
In the Southern Hemisphere this is the summer solstice. Christmas in Australia, South Africa, Argentina and New Zealand falls within days of the longest day of the year.
Earliest sunset and latest sunrise
One of the most surprising facts about this solstice is that the earliest sunset and the latest sunrise are not on the shortest day. At around 40 degrees north, the earliest sunset comes in early December and the latest sunrise in early January.
The reason is that solar noon, the moment the Sun is highest, shifts later by about half a minute each day in late December. Two effects combine to cause this: Earth is near perihelion and moving fastest in its orbit, and the tilt of the axis adds its own shift at this time of year. So while the total length of the day bottoms out at the solstice, the whole block of daylight is sliding later on the clock. Sunsets are already getting later before the solstice, while sunrises keep getting later until early January.
For anyone tired of dark afternoons, that is good news: evenings start to brighten a few weeks before the solstice.
Polar night and midnight sun
North of the Arctic Circle, at about 66.6 degrees north, the Sun does not rise at all around the December solstice. Towns such as Tromsø in Norway and Utqiaġvik in Alaska spend weeks in polar night, although near the circle there is still a few hours of twilight around noon.
South of the Antarctic Circle, the Sun stays above the horizon all day and night. Research stations in Antarctica are in constant daylight.
Solstice monuments and traditions
Several ancient structures line up with the December solstice. The passage tomb at Newgrange in Ireland, built over 5,000 years ago, admits a beam of sunlight down its passage to the inner chamber for a few mornings around the winter solstice. At Stonehenge in England, the main axis lines up with midwinter sunset in one direction and midsummer sunrise in the other.
Many cultures mark the date too. In China and East Asia, the Dongzhi festival celebrates the winter solstice, and in Iran, Yalda Night is observed on the longest night of the year.
After the solstice, the northern days grow longer until the March equinox, when day and night are roughly equal again.