Light Pollution: A Primer Dan Caton, Professor and Observatory Director NCAM 10/4/2014

Warning! I will ruin the nightscape for some of you!

Don’t mean to offend… Most lighting is not designed.

The basic problem: Sky Glow Light from fixtures reflects off particles in the sky— ”Sky Glow.” Large cities visible from tens of miles. The stars are not brighter here in the country …

…The sky is darker! When it is dark enough, you can see the stars. −Persian proverb. Three Cups of Tea, p. 7

My first concern: our Dark Sky Observatory Off the Parkway, about 20 miles from Boone.

More than astronomers-- 100,000 hobbyists

Just as important

The Global Problem

Light “Made in the USA”

What’s Wrong With this Picture?

Closer to home You are here!

Boone, ~50 years ago…

… more recently

Where does the sky glow come from ? Poor fixture design Lack of shielding Over-lighting Poor installation Market pressure

One of the worst fixtures: Floodlights Almost horizontal No shielding At night …

Boone McDonalds

Better: Full Cut Off (FCO) “Shoebox” design Why do you think they are chosen? … Appearance in the daytime! At night …

Boone McDonalds after recent renovation

Sidewalk + street Lighting

Acorns/globes More light up than down

Residential Post Mounts Not many FCO fixtures available This unit by Minka

Residential Entry Ditto: not many FCO fixtures available This unit also by Minka Soffit lights better— also do not draw bugs

Billboards: the Bad Way Uplighted Most light reflected into the sky Often on all night

Roadway lighting: Glare from cobra heads Filament below reflector Glaring to driver Light polluting

Better, Full Cut Off Fixtures

“Security” Lighting “Dusk-to-dawn” Security or lighthouse? Refractor very glaring and light polluting Frequent light trespass and neighbor problem Installed by amateurs and utilities

Private Security Lights

The Glare at Night (From high up, too!)

Solution: Sky Cap GE SkyGard shown Hubbell available Total FCO See results …

The Capped Light at Night

The Data

Health concerns Baby sea turtles attracted to street light Few years ago: 60 died due to Hilton Head Proposal Cancer and melatonin production in people

So, this is more than just annoying at hotels

Car Sales Lots Often grossly overlit This one at ~35 fc (?) but very glaring (this in Lenoir) Use astronomically unfriendly metal halides Can use sodium with 10% white to get color rendition

…This in Tampa like this (Tampa)

Wall Packs One of the worst fixtures for pollution as well as glare (this in Lenoir at charity organization?) Are available in FCO. (See in a moment)

Wall Packs (or floods) also used in ATMs Glare! Could you see a criminal? … He can see you! This at the otherwise good…

…Lenoir Bank of Granite: FCO wall packs

Sports Lighting Usually done poorly with lots of light pollution and light trespass. Can be done well as shown here, using fixtures like ….

Fixtures with light control

New Watauga High Stadium

Gas Station Canopies

Compare to this (Boone)—6 fc! (used to be 60)

How You Can Help Look at your own lights–are they needed? Could you have it capped? Put it on a switch, timer or a motion sensor. Put in a lower wattage bulb. Where do you eat out? Do the restaurants have glaring lights? If so, complain! … Are there some roadside lights that bother you as you try to drive? Complain!

Is there a street light that shines into your window at night? Call up the utility and ask for them to put a sky cap on it. Don’t settle for simple spray painting of the fixture’s lens! Write letters to your newspaper…. Teach your friends about good and bad lighting–point it out when you are out with them at night. (Spoil their view…)

Spend some time at and become (more of) an expert! Join the IDA. Develop a local ordinance.

Concluding… Like the background on this presentation, let’s make the orange glow of sodium vapor go away. Thank you for your time and attention.