Date: April 25, 2009


Title: The Good, The Bad and The Ugly of Outdoor Lighting

Podcaster: Dan Duriscoe and Teresa Jiles

Organization: U.S. National Park Service

Description: April 25, 2009 marks the 62nd anniversary of the Theodore Roosevelt National Park. Established on April 25, 1947, this landscape inspired a young Theodore Roosevelt, to say:
‘After nightfall the face of the country seems to alter marvelously, and the clear moonlight only intensifies the change. The river gleams like running quicksilver, and the moonbeams play over the grassy stretches of the plateaus…The Bad Lands seem to be stranger and wilder than ever, the silvery rays turning the country into a kind of grim fairyland.”

It is in this spirit by honoring President Roosevelt, we offer conservation advice to protect these precious spaces from the intrusion of light pollution. This podcast discusses what makes a light good or bad for the night, and examines a few ugly wasteful lights and what can be done about them.

Bio: The US National Park Service was established “to conserve the scenery, the natural and historic objects and the wild life therein”. This commitment includes preserving the scenery of the night sky. With the rapid pace of urbanization, light pollution now dominates the night skyline for most of America. Parks suffer too from light pollution spilling across park boundaries from lights near and far. In order to stem the tide of light pollution, many national parks are striving to set an example by redesigning park lighting to be dark sky friendly and energy efficient. In fact, Natural Bridges National Monument in southeastern Utah, is the first International Dark Sky Park, certified by the International Dark Sky Association. This podcast discusses what makes a light good or bad for the night, and examines a few ugly wasteful lights and what can be done about them.

Today’s Sponsor: This episode of “365 Days of Astronomy” is sponsored by Jim Stratigos. “To my lovely wife Janie who has put up with my hobby for years and followed me in search of dark skies.”


[Guitar music from Angel Eyes’ introduction]

Introduction (Dan):
This podcast is presented by the U.S. National Park Service Night Sky Program. My name is Dan Duriscoe. April 25, 2009 marks the 62nd anniversary of the creation of Theodore Roosevelt National Park, located in North Dakota.

Theodore Roosevelt, our nation’s 26th President, is considered to be our country’s “Conservationist President.” In his day, natural dark skies were common and light pollution was unknown. His experiences in the outdoors of our country led him to aggressively protect its natural scenery, which includes the sky full of stars. It is in the conservation spirit that we honor President Roosevelt and his insight.

Today my colleague Teresa Jiles and I present a subject related to astronomy that is as close as your own backyard. Outdoor lighting: the good, the bad and the ugly.
We portray a discussion between two neighbors. Dan has just purchased a home in the country, and is eager to install outdoor lighting. His neighbor, Teresa, tries to advise him to use caution and common sense, with a little help from Clint Eastwood and Sergio Leone.

[Knock on the door, door opens]

Teresa: Hi, I’m Teresa, your neighbor across the small hill over there. I just thought I’d welcome you to the neighborhood.

Dan: Hi Teresa, I’m Dan, pleased to meet you. What’s that? Cookies! How kind. Well, let’s have some out on the patio, it’s such a great night. [Crickets chirping] Here have a seat. Wow! Look at those stars.

Teresa: We have a wonderful night sky here, but if you go around to your back yard you’ll see a big dome of light from the city part way up the western sky. I sure hope it doesn’t get any worse.

Dan: Yeah, I‘m glad to get out of there finally and get this place in the country; it’s been my life’s dream. Two acres, lots of elbow room. But it sure is dark out there, I’m going to have to get my electrician buddy to come out here and install some outdoor lights so I can see what’s going on.

Teresa: Actually, I was going to ask if you could turn off that porch light, it’s awfully bright and right in my eyes and I can’t see a thing.

Dan: Oh, really? Sorry, I just put a 100 watt bulb in it. I’ll turn it off and get the oil lamp. I’ve got one in a box with the patio stuff right over here somewhere. I haven’t quite moved in yet.

[Sound of rummaging around through stuff.]

Here it is.

[Sound of match being lit}

There, I’ll turn this off…[click], how’s that?

Teresa: Oh, much better, thank you. Before you turn your electrician friend loose on the place, I hope you’ll think about why you need these lights and how you expect to use them. Give your design a little planning.

Dan: Oh come on, this isn’t rocket science. I just want to be able to see what’s out there. There’s a lot of land here.

Teresa: Well, like any other building project, outdoor lighting takes planning. And you should think about the consequences of what you’re going to build and use on the environment and your immediate surroundings, namely, me. Also your other neighbors, and the wildlife around here. I personally think in general, overuse of outdoor lights are everywhere I go, and I see plenty of examples of the good, the bad and the ugly.

[Clip from soundtrack, near the end of The Good, The Bad and The Ugly (GBU) film]

Dan: What was that? Did you hear something out there?

Teresa: Take it easy. You need to live out here a while and get rid of some of those city nerves. Now you take that 100 watt bulb on your porch there. How about switching to a compact fluorescent? Maybe something with 7 watts? Think of how much electricity you’ll save.

Dan: Oh, yeah, I’ve seen those spiral looking lamps in the store. The power company says we should get rid of all the incandescents. I just haven’t gotten around to it yet. I guess there’s a big reward in energy savings.

[Clip from GBU film – Blondie: “Yeah, but you don’t look like the one who’ll collect it”]

Dan: What did you say?

Teresa: Nothing. Besides the energy saving lamps, take a look at the fixture. Your porch light has a clear glass “carriage lantern” style. That bulb shows right through the glass and it produces a lot of glare. You want the light on the ground so your guests can see the door without tripping on the stairs, not in their eyes where it blinds them. Think about getting a shielded fixture that points light down.

Dan: But with this I can see all the way into the driveway. A shielded light wouldn’t do that, would it?

Teresa: Lighting engineers say that trying to throw light horizontally more than about 3 times the fixture height is a poor design. Your light is about 7 feet high, so you shouldn’t try to illuminate anything more than about 20 feet from the house with it. Maybe you could get your buddy to put in some low voltage walkway lights to see your way all the way out to the driveway. You can get 2 or 3 watt LED lights and that will do the job.

Dan: You seem to know a lot about this. I had no idea there were so many kinds of fixtures and lamps available. I figured a light is a light.

[Clip from The Outlaw Josey Wales: “Where’d you ever get an idea like that”]

Dan: What?

Teresa: Here have another cookie. Um, there are thousands of fixtures, lamps, mounting types and controls out there.

[Music “Ecstasy of Gold” in background]

Let’s see you can get wall packs, sconces, floods, cobra heads, shoeboxes, forward throw, side throw, spots, façade lights, landscape lights, accent lights, canopy lights, and recessed lights. There are globes, and sag lenses, and lanterns, reflectors, mushrooms, bollards, wedges, acorns, and louvers. You can get incandescents, halogens, mercury vapor, high pressure sodium, low pressure sodium, metal halide, ceramic metal halide, compact fluorescents, tube fluorescents, low temperature ballasts, …..

Dan: OK, OK, I get the picture. But we’re talking about a few little lights here, how can they possibly make much difference in the vastness of the night sky? I may be new around here, but there’s so much open space out there, right?

[Clip GBU film—Blondie: “Idiots, its for you”]

Dan: I beg your pardon?

Teresa: I said that the fact that it is so dark and open out here means you need a lot less light to see just fine. Your eyes can adapt to the darkness when you go outside and just a little bit of light is enough to help you see. And the critters that live in all that open spaces are used to it being pretty dark, some of them depend on it for survival, not to mention those of us in our houses across the hill.

Dan: You know, as we’ve been sitting here I do notice more and more stars, and the landscape doesn’t seem so dark to me either. I can see the rocks; the bushes and I can see the shadow of the house caste by the city glow. And look at that really bright clump of lights way over there, what’s that?

Teresa: That’s the electric transformer station 10 miles away on the high voltage lines. I have no idea why they have to light it up so bright all night. At least they could shield the light.

Dan: Ten miles away? Wow. I see what you mean about the shielding.

Teresa: I’ll bet your porch light can be seen from miles away. That’s what we call light trespass; putting up lights that infringe on other people’s right to starlight. This land is pretty open and the air is pretty clear around here most of the time. That’s part of the reason the stars look so good.

Dan: I see a lot of these “farm lights” down the road a ways on power poles. A friend of mine says the power company actually put his in for free; it has a photoswitch on it so it automatically goes on at night and off in daylight. I think people just forget about lights that are on all night, they get used to it.

[Clip from The Outlaw Josey Wales: “There ain’t no forgettin’]

Dan: Uh, how about another cookie?

Teresa: I shouldn’t, but OK. Thank you. Your friend’s light is probably an old mercury vapor. If so, it sucks up lots of power all night long and producing a lot of wasted light and energy. I think those dusk to dawn pole lights are the scourge of the west. Talk about bad and ugly. Most of them are not shielded at all, and almost half the light goes directly into the sky. They attract a lot of insects and in turn the bats that come to feed on them.
That reminds me color of a light is also important. You see your red wine in that glass sitting over there? Doesn’t it has a lovely color in the yellow flame of the lamp? Did you know that yellow and red light is much easier on the dark-adapted eye than white light, and it doesn’t attract as many insects or the nastier insects and the animals that eat them?

Dan: I’ve seen the yellow bug lights in the hardware store. You know you’ve given me a lot to think about. I’m really enjoying this wonderful evening under the stars.

[Main GBU theme music]

Conclusion (Teresa): Whatever Dan chooses to install, I’m sure he’ll consider his neighbors, the birds, bats, and bugs, and the planet in terms of how much energy is consumed and carbon dioxide is produced as a result.
Mostly, he just needs to use common sense rather than fear or “tradition” with outdoor lights. It may seem that residential outdoor lighting is insignificant, but a good design can pay big dividends, especially with your neighbors. Use the minimum amount of light needed, make sure there is no light trespass, and use red or yellow light whenever possible.

As President Theodore Roosevelt said:
“We have fallen heirs to the most glorious heritage a people ever received, and each one must do his part if we wish to show that the nation is worthy of its good fortune.”

End of podcast:

365 Days of Astronomy
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