Worldwide, recent studies have shown it's increasing at the rate of 10% a year . Where I live, there's always a light in your face -- yard lights left on all night, poorly designed outdoor building lighting that beams light in every direction except the crucial one -- downward -- and over-the-top, unshielded security lighting.
Efforts to improve the situation make me hopeful, but overall more lights are going up or left on than are dimmed or turned off when unneeded. People living in Northeastern Minnesota are fortunate to still find dark skies relatively near their towns, but we're the exception. For much of the country, a minimum of an hour's drive is required to reach a reasonably dark sky.
Even when we do find a starry sky, a single mercury vapor lamp on a tall pole or garage lights from one or two homes in the distance damage the darkness by constantly drawing our eyes to the light. I think how little effort it would take to turn them off when they're not needed for their primary task -- to safely find our way to the door in the dark. As a kid, my parents would always remind me to shut off the lights when I'd leave a room. "It saves electricity." At the time I chaffed at the rule, but they were right.
Is an all-night "security" light illuminating a lawn or driveway actually serving a purpose when you're inside your house sleeping? If it's burglars you're worried about, the most common time for break-ins is between 10 a.m. and 4 p.m. when most people aren't home. If you're still concerned, purchase a light with a motion sensor.
Poorly shielded city, industrial and residential lighting create a light dome above a town. You can see them from a distance while driving at night. Small towns have small domes; big city domes encompass the sky for miles around. Light domes dim the stars for both the city's residents and those living nearby. As a dome grows, more stars are subtracted until the sky glows a sickly gray at night and the number of stars dwindles from thousands to dozens.
Why is darkness important? Instinctively, we fear it. Bad things lurk there, right? So why not just get rid of it? What's to lose? Just a piece of our sanity. That's what's to lose.
If you've stood under a dark sky, you know how good it feels. All those stars! You don't need to know a single scientific fact to experience awe at the sight. Pure, unmitigated wonder still has currency in my book, and a sky jammed with stars is one of my favorite ways to renew it.
We all need to recharge once in a while. Pausing to appreciate the beauty of a starry night momentarily stops the constant noise coming from our brains so we can soak in the eternal present. Muting the internal din also allows us to hear that little voice we all have inside and tap into its wisdom. Where are we? How did we arrive at this place in life? What might the future hold? The voice knows.
Further, the sight of a sky carpeted in stars awakens our curiosity. We want to know more about what's up there, including if other beings are staring back at us and pondering similar questions. Severing ourselves from the greater cosmos not only disconnects us from nature, but also shrinks our perspective, which limits life's possibilities.
Walking outdoors on a dark night with the stars and moon overhead has helped me work through my worries and issues -- disagreements with family members, ideas for stories, the lifelong pursuit of becoming a better human or choosing the right words for an apology. I also enjoy all the things that happen on the starry stage like picturesque conjunctions, sudden meteors and the parade of constellations that changes with the seasons.
While the Northland has relatively dark skies, at least away from city centers, darkness diehards like myself often make special trips to find even better skies. I spent the past week in the Oklahoma Panhandle with several other amateur astronomers doing just that. We observed with telescopes and photographed to our heart's content under a blizzard of starlight wrapped in the ribbon of the Milky Way.
Several nights in, it occurred to me that the sky there was the same (or nearly so) as the one under which our ancestors lived for millennia, long before gas and then electric lighting became commonplace. Even at midnight the stars, planets, natural airglow, and the zodiacal light cast enough light to find one's way at night.
Can we still hold on to a piece of that world? We can. Awareness is the first step, and the second is simple -- switch off an unneeded light.