The longest night of the year is upon us: Dec. 21 is the winter solstice, when the sun takes its lowest and shortest path through the sky and the Northern Hemisphere sees its shortest period of daylight.
In Washington, D.C., there are 9 hours and 26 minutes of daylight on the winter solstice, with sunrise at 7:23 a.m. and sunset at 4:49 p.m. Starting Wednesday, the day will be a scant two seconds longer, according to TimeandDate.com. But come early January, daylight will increase by about a minute per day, with most of the additional light tacked on to the evening.
I always pay close attention to the winter solstice, which signals the inevitable return of the sun’s light as we climb out of the darkest stretch of the year. For the past six months, we’ve watched the sun gradually sink lower in the sky with each passing day, causing shadows to elongate and daylight hours to continually shrink.
But when the winter solstice arrives Dec. 21, our descent into darkness finally pauses before reversing direction, much like a pendulum does as it swings back and forth. On the solstice, the sun takes its lowest and shortest path across the southern sky, which is why it’s dark for a good portion of the day. A sunny winter day can feel blindingly bright, even rejuvenating, as the shallow rays wash over the landscape. Yet the winter sun is always fleeting and never far from the horizon.
That’s especially true at more northern latitudes, which experience greater extremes in daylight between summer and winter because of Earth’s tilt.
I’m a D.C.-area native but spending winter in Maine, where the days are noticeably shorter than I’m used to. At this latitude, roughly as far north as Green Bay, Wis., the sun spends just eight hours and 50 minutes above the horizon on the solstice, compared with about 9½ hours of daylight in the nation’s capital. It will be a full month before the length of day here is the same as it is in D.C. on Dec. 21.
The shorter days are especially pronounced because Maine — like much of New England — is in the eastern reaches of our common time zone. Despite being farther north, Maine juts so far to the east that the sun here actually rises 14 minutes earlier than in D.C. However, it also means Maine sees some of the earliest sunsets anywhere in the Lower 48. Along the mid-coast of Maine, the earliest sunset comes around 3:56 p.m., and evening darkness starts nearly an hour earlier than in D.C.
Living at a more northern latitude teaches you not to take the sun’s light for granted. The days are so short, they seem to pass quickly. The soft, pink hues of morning light slowly crescendo into a brief hour or two of midday brilliance, before the afternoon sun drops back toward the horizon, and suddenly it’s getting dark again.
Of course, even in northern New England, the winter solstice sees more daylight than parts of the Upper Midwest or far northern tier. In Alaska, the winter sun hardly makes much of an appearance. On Dec. 21, Anchorage sees about 5½ hours of daylight, while in Fairbanks, the sun is up for just 3 hours and 42 minutes. North of the Arctic Circle, the sun doesn’t rise at all; apart from a few hours of faint twilight, the winter solstice is shrouded in darkness.
Hours of daylight on the winter solstice. pic.twitter.com/14KiCFmL9q
— Brian Brettschneider (@Climatologist49) December 22, 2019
However little daylight we see around the solstice, accepting — or even embracing — the dark days of winter is one way to stay energized during these longest nights of the year.
Fortunately, we’ve already turned the corner toward more evening sunlight. Though the solstice has the least daylight, our earliest sunsets are already behind us. D.C.’s earliest sunset was at 4:45 p.m. on Dec. 7. On the winter solstice, sunset is four minutes later than it was in early December.
Meanwhile, even as the days start to lengthen, the time of sunrise will continue to shift later until the first week of January. This misalignment between the earliest sunset and latest sunrise happens because of Earth’s tilt and the fact that we orbit the sun slightly faster this time of year.
As we head past the winter solstice and into a new calendar year, the increasing daylight always happens slowly at first. But whatever the rest of winter brings, brighter days are ahead even if we can’t quite see them yet.