The significance of the solstice: Lights brighten dark skies of winter
The pale winter sun sank beneath the horizon at 4:21 p.m. yesterday. Fifteen hours of darkness ensued, making it the longest night of the year. It was a special night, the eve of the winter solstice.
Chances are most suburbanites were unaware of the long dark night and its significance. Shoppers went on shopping in well-lighted stores, drivers went on driving on well-lighted streets, teens went on texting with well-lighted phones, and people went on watching television in well-lighted homes. Holiday lights shone from every mall, every neighborhood, and every street in town.
The winter solstice, falling smack dab in the middle of the high-watt holidays, is easily lost in the ubiquitous glare of these artificial lights.
The solstice is an astronomical event that heralds a turn in the seasons. It's best understood if you picture the earth with an imaginary stick through it, called the axis. It turns on its axis while it orbits the sun. Since the earth took its first spin around the sun ages ago, it's been a bit askew on its axis. It tilts so that half the year the northern hemisphere leans toward the sun (summer for us) and half the year the southern hemisphere tips sunward (summer for the folks Down Under).
When the planet starts leaning away from the sun, the days grow short and the nights grow long. In late December the planet tilts as far as it's going to go, and we experience the longest night of the year. That's Solstice Eve. The winter solstice itself occurs today at 11:47 a.m. when the sun begins its slow tilt back toward the sun. From this point on, the length of daylight will increase ever so slightly, an imperceptible few seconds a day at first. The seconds will accumulate to minutes and then hours. Come March, the vernal equinox will mark the time when the length of day equals the length of night. In June the summer solstice will bring the longest day and shortest night of the astronomical year.
People in ancient cultures around the world not only took note of the winter solstice, they celebrated it. While not knowing the astronomical why's and wherefore's of the solstice, they anticipated and reveled in the return of the sun. Preindustrial cultures, particularly agrarian societies, lived in synchrony with seasonal cycles of day and night, light and dark, warmth and cold. There were no options to do otherwise - until the advent of electricity.
Thomas Edison's invention of the incandescent light bulb and the distribution of electric power generation led to the illumination of homes, neighborhoods, cities and roadways. Lighting the night was an exciting venture and it opened a world of nocturnal possibilities. Indoor lighting allowed people to be active at night. Factories could be productive 24/7. Street lighting made it safer to travel at night. Flood lights gave people a sense of nighttime security.
In no time at all, the technology of electric lights took over the Christmas holidays. Precursors to decorative outdoor holiday lights glimmered in big cities at the turn of the century. As technology advanced and lighting became more affordable for the average homeowner, strands of wire with small sockets for colored light bulbs became all the rage. Such lights adorned Christmas trees indoors and were strung along eaves, over shrubs and around lamp posts outdoors. Soon there were contests (sponsored, of course, by General Electric) for the best holiday light displays in suburban neighborhoods. In the 1950s outdoor Christmas lights were a well-established tradition in the United States, and by the sixties entire neighborhoods endeavored to create a seamless stream of holiday lights, eave to eave, hedge to hedge, and lawn to lawn. The cumulative effect was bedazzling. And the longest night of the year faded in the brightness of the lights.
The holiday lighting trend has grown to enormous proportions today. There are enough rows of lights on some rooftops to land a 747 let alone a cargo-laden sleigh. Eaves drip with such brilliant icicle lights you could have open heart surgery on the sidewalk. But strings of lights are just a part of the brilliant extravaganza. There's a lot more decor to go with. Inflatable icons of elves and snowmen are arranged in one front yard, while baby Jesuses juxtaposed with jolly Santas share the spotlight next door. Red-nosed reindeers (schnozzles aglow) graze outside mangers while radiant wise men approach bearing gifts.
Granted, this is all in good fun and holiday cheer is what the season is all about. The excess of effulgence, however, has drowned the solstice sky. Look to any horizon and you will see a dull orange hue, the ubiquitous glow known as light pollution. Pollution is hardly a term with a festive ring to it - and only a Grinch would grouse about lights at Christmas time, right?
Such a Grinch might have a point, though. Perhaps in all the excitement about lighting up the world at Christmas, we've lost something. The longest night of the year is no longer dark. The return of the sun is no big deal when it's never really dark. Light pollution has insidiously disconnected people from the rhythm of the seasons and the cycles of nature. The winter solstice, once cause for festivities and celebration, is just another day in the countdown to Christmas.
But there are good tidings to bear. Light pollution is the only form of pollution that has a low-cost and highly effective solution. First, there's the plug. Pulling it is easy and saves you money. Then there's the dimmer switch. Thirdly, there are many ways to mount light fixtures so that the light doesn't spread needlessly toward the heavens - or into your neighbor's bedroom. The International Dark Sky Association has an excellent Web site full of practical tips and alternatives to reduce the impact of light pollution. Check out www.darksky.org for lots of good information.
There's no need to put the kibosh on all holiday lights. It's important, though, that the lights don't blind us from the solstice and all the nuanced changes it brings to the natural world. Darkness comes, light returns, and seasons turn. Go outside tonight and dig the darkness. Search for that star in the December night sky. And be of good cheer, knowing that the sun will return just a little bit earlier tomorrow morning.
Winter Solstice nature walk: Bundle up and join Forest Preserve District of Kane County naturalists in celebration of the winter solstice at the Dick Young Forest Preserve in Batavia from 4 - 5 p.m. today, Dec. 21.
This family-friendly winter walk will highlight the changes of the season at the winter solstice. We'll look for signs of winter animals and adaptations of plants in the cold months of the year. For registration details, call (847) 741-8350 or e-mail programs@kaneforest.com.
• Naturalist Valerie Blaine enjoys dark night skies and winter sunrises. You can reach her at blainevalerie@kaneforest.com.
<p class="factboxheadblack">Joy to the world, the LED has come?</p> <p class="News">The light emitting diode, or LED, is a relatively new "green" technology. </p> <p class="News">LEDs use less energy, last longer, and are more durable than traditional incandescent lights. Energy-conscious consumers have jumped on the LED bandwagon with all good intentions.</p> <p class="News">Not so fast, says the International Dark-Sky Association. Although LEDs are energy efficient, they emit a bluish-white light that "threatens visibility at night and jeopardizes the nocturnal environment worldwide." In a statement issued by the IDA, managing director Pete Strasser explains, "These lights are known to increase glare and compromise human vision, especially in the aging eye. Short wavelength light also increases sky glow disproportionately. In addition, blue light has a greater tendency to affect living organisms through disruption of their biological process that rely upon natural cycles of daylight and darkness.</p> <p class="News">"For only a modest improvement in outdoor lighting efficiency, these new sources dramatically escalate the environmental damage caused by artificial lighting."</p> <p class="News">As with any new innovations, more research is needed about LEDs and the technology must be tweaked. </p> <p class="News">"If you plan to buy an LED light bulb and install it outdoors," wrote Kati Stevens on the Planet Green Web site, "make sure your lamp or fixture is properly shaded, or the LED, like any other light, will (harm) nocturnal wildlife and impede our view of the skies."</p>