The winter solstice isn’t named for the “shortest” day, nor is it named for the longest night, nor even the beginning of winter. The name solstice comes from Latin, and it means, “sun stands still”.
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| Winter sun in the Mohonk Preserve / Image: Kate Comisso |
The answer lies in the south. Those of us in the USA, Europe, Canada - anywhere north of the Tropic of Cancer - never see the the sun directly overhead, even in the middle of the day. Instead of craning our necks to look straight upwards, we must look up a bit and south a bit. There, in the middle of the day on the summer solstice, we will find the sun higher than it will be at any other moment of the year. Following that, as summer turns to falling leaves turns to the first frost, the sun will appear to climb a little less high every day. By the time winter approaches, an observer might wonder if the sun will rise above the horizon at all.
Then something amazing happens. The sun stands still. For a few days before, and after, the winter solstice, the change in the sun’s midday height is so tiny, it is as if the sun has stopped sinking altogether but has not yet started to climb.
In ancient times, people celebrated this low point of the sun’s journey, knowing it marked the start of the return to spring and growth. You can imagine the feeling the winter solstice must have created in someone who worshiped the sun, or even in someone that just lived closer to nature than we do now. Time to throw a party. A week-long party named Saturnalia, in the case of the Romans. Meanwhile Britain’s Druids decided to mark the occasions of the solstices by lugging 4-ton stones from Wales to Stonehenge, 140 miles away. It’s fair to say they took the solstices pretty seriously. I personally like the simplicity of the Scandinavian approach, lighting the yule log to welcome back the warmth and light of the sun.
You can see the apparent pause of the sun below, thanks to an NOAA website that provides the height of the sun in the sky for any place at any time. I plotted the sun’s midday height in London’s sky on two days of each month for a year, from June 2017 to June 2018. Around the time of the summer and winter solstices, there is very little change in height, the sun stops sinking or climbing.
Of course, the winter solstice is still technically the shortest day, the day of the year when the northern hemisphere receives the fewest hours of sunlight. Well, hours of daylight is overstating it. As you might expect from a time when the sun stands still, the difference is small. In London on the day after the winter solstice, you can look forward to a mere 2 seconds of extra daylight. Enjoy. The lengthening day will amount to less than two-and-a-half minutes of extra daylight a full week after the solstice. Compare that to mid-March, when London daylight will lengthen by almost 4 minutes each day. Over the course of a week that’s almost half an hour’s extra light to look forward to.
So next time you find yourself squinting into the low midday sun, stand still a moment and think of spring: a time of warmth, growth, and the sun’s return to great heights.
Links
To calculate how high the sun climbs each day where you are, select a place, a date, and set the time to solar noon (halfway between sunrise and sunset):
I took the daylight lengths from here:
Further reading
To understand the shape the sun traces over a year:
On the solstice and ancient celebrations:
On Stonehenge:
Live Science
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