Lights Out, Everyone!

Like it or not, we've become a 24/7 society — and, like it or not, nighttime activity requires some illumination to help us find our way along streets and sidewalks.

Harsh lights in residential neighborhood
Do these harsh, glaring lights look like those in your neighborhood or, worse, the ones in your front yard?
S&T: J. Kelly Beatty
But it's easy to see that very little outdoor lighting is done well. Too many fixtures send light streaming up into the sky, or provide far more light than is necessary, or are simply left on when they're not needed. For all these reasons, light pollution has become the universal bane of anyone who appreciates the starry sky.

Five years ago, a high-school student named Jennifer Barlow decided it was high time to raise our collective consciousness about the growth of light pollution. So she launched National Dark-Sky Week. The event has been gaining steam every year, and it's gained the endorsement of the International Dark-Sky Association, the American Astronomical Society, and the Astronomical League.

This year National Dark-Sky Week runs from March 29th to April 4th. It's timed to coincide with Earth Hour, another night-sky-friendly effort sponsored by the World Wildlife Fund. To participate in Earth Hour, simply turn off unnecessary lights (particularly outdoor lights) in your home or business from 8 to 9 p.m. on March 29th.

That small effort is more than just symbolic — it will achieve a small but real saving in electricity and, in turn, the coal or oil that's likely being burned to create it. And the simple act of identifying a light to turn off might convince you that it didn't need to be on in the first place, or at least that it doesn't need to be on all night long.

Did you know that keeping a single 100-watt light bulb on all night, every night, requires more than 400 kilowatt-hours of electricity each year — the energy equivalent of burning more than 500 pounds of coal, and costing you (typically) more than $50 per year?

So I urge you to get behind the NDSW effort. For more information, see the press release issued by the IDA. And for good advice on how to improve the lighting outside your home, click here.

5 thoughts on “Lights Out, Everyone!

  1. John Ståhle

    Use the energy you need – don’t waste any.

    The birds read only morning papers so there aren’t any good reasons to light up the trees at night.

  2. Mick

    Is there some literature or info on lights that are better at preventing light polution. There are numerous places where this info could be forwarded (there is a preservation society arround the lake our cottage is on in northern Mich. There are neighbors (huge light poluters) who I’m sure would be supportive if I could hand them a list of lights with some form of schield or protection.

    Any ideas???

  3. Keith

    Direct them to the International Dark-Sky Association’s web page:

    Look for the ‘Approved Fixtures’ menu choice. What you want is what is called a “full cutoff” fixture. It doesn’t waste light throwing it skyward or beyond your own property.

  4. Martin

    Did you know that keeping a single 100-watt light bulb on all night, every night, requires more than 400 kilowatts of electricity each year

    …That’s kilowatt *hours*.


    Martin, you’re right! I’ve made the correction. — Kelly Beatty

  5. Belinda

    Trying to find Jennifer’s website to check out more detailed info. I clicked on the link National Dark-Sky Week, but my computer could not locate it at all. Any further suggestions or ideas?

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