# Light Pollution Getting Worse



## CroMAGnet (Jul 22, 2012)

It's a beautiful night tonight. A flashaholic's dream with just a sliver of a moon fighting back the starry sky. 

It seems that light pollution is getting worse. There was a PBS Special about the problem.
http://www.suntimes.com/entertainme...the-stars-in-chicago-and-thats-dangerous.html


Check out the amazing Google Light Pollution Map too
http://googlemapsmania.blogspot.com/2011/12/light-pollution-on-google-maps


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## lightwater (Jul 27, 2012)

I was in central Australia a few years back. It's amazing just how clear the skies were from all sorts of pollution. I don't think you could stuff another star in the sky. Hopefully one day we can clear up the pollution from our "civilised" societies. There would be better health all round, clean air to breath, see the sky!


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## fyrstormer (Jul 27, 2012)

Light pollution isn't getting worse. There are all sorts of new standards for outdoor lighting fixtures that don't allow stray light to escape upwards. If anything is getting worse, it's suburban sprawl, which means there are more outdoor lights total, regardless of how good they are at containing stray light. Also a problem is the sulfur content of the air, which makes it more reflective and dims the incoming starlight regardless of any light pollution.


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## VegasF6 (Aug 2, 2012)

The story mentions Chicago as being the worst offender. I can't imagine anywhere being worse than Las Vegas on this issue.


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## SemiMan (Sep 2, 2012)

Dark sky compliant lights are a nice concept, but they don't prevent light from reflecting upwards!

The issue is not so much the type of lights we use, but just how much of them and how bright they are. 

The IES enhanced security level for parking lots is 5 lux minimum. Most retail lots are 4 or more times that. Dealerships are 100 times that which may be okay when they are open, but the lights are left at that level all night!

Semiman


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## Norm (Sep 2, 2012)

I'm so glad I live in a rural area. 

Norm


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## mvyrmnd (Sep 2, 2012)

Norm said:


> I'm so glad I live in a rural area.
> 
> Norm



+1


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## CamoNinja (Sep 2, 2012)

+2



Norm said:


> I'm so glad I live in a rural area.
> 
> Norm


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## cerian (Apr 1, 2013)

A building closed to where i live installed a LED display matrix, it literally light up half of the night sky and it is not comfortable to look at. I hope the light intensity is going to down a bit as it age.


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## LEDAdd1ct (Apr 6, 2013)

Dark Sky Finder

I think one of the reasons I like camping is the *dark* and the *quiet*. 

The noise of my hard drive motor, a pigeon cooing, the refrigerator motor, birds, heating pipes...

Being somewhere completely quiet and completely dark is disconcerting at first and then incredibly,
soul-stirringly rewarding.


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## Anders Hoveland (Apr 6, 2013)

Ironically, the switch to LED streetlighting could make light pollution even worse. The yellow-orange frequency in the sodium line diffuses in the atmosphere less than the higher frequencies from LED. Then there is the color contrast, it is easier to see stars against the orange polluted background than a bluish white polluted background.


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## jtr1962 (Apr 6, 2013)

Anders Hoveland said:


> Ironically, the switch to LED streetlighting could make light pollution even worse. The yellow-orange frequency in the sodium line diffuses in the atmosphere less than the higher frequencies from LED. Then there is the color contrast, it is easier to see stars against the orange polluted background than a bluish white polluted background.


LEDs might help more than hurt because nearly 100% of the light can be directed exactly where you want it. HPS/LPS lights direct a fair percentage of their output upwards. When it snows or is foggy, I noticed the sky has a hazy orange glow. Also, due to the higher blue content, the apparent brightness of LEDs at any given lux level is higher. Therefore, you can reduce lighting levels without sacrificing perceived output. That should also help. The point here is we really don't know how LED will affect the light pollution situation until a large city has mostly LED streetlights.


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## SemiMan (Apr 6, 2013)

jtr1962 said:


> LEDs might help more than hurt because nearly 100% of the light can be directed exactly where you want it. HPS/LPS lights direct a fair percentage of their output upwards. When it snows or is foggy, I noticed the sky has a hazy orange glow. Also, due to the higher blue content, the apparent brightness of LEDs at any given lux level is higher. Therefore, you can reduce lighting levels without sacrificing perceived output. That should also help. The point here is we really don't know how LED will affect the light pollution situation until a large city has mostly LED streetlights.




There is nothing inherent in LPS/HPS that the light has to go upwards. Many progressive areas have been installing full cutoff HPS fixtures for some time and I am finding more and more cities, towns, etc. are insisting on at least semi-cutoff if not full cutoff fixtures for all installations no matter the technology. I have not seen movement to the more modern BUG standard yet, but it should come.

Apparent brightness does not impact used lighting levels at all though. Apparent brightness and real world impact do not always coincide.

For roadway lighting due to the speed of movement, the central cone of vision is the most important, hence photopic or at a bare minimum mesopic levels are used. For slow speed residential roads you may be able to reduce lighting levels 25%(more?), with the advantage diminishing as the speed goes down.

Where you could get the most benefit is parking lots, but I find that more newer parking lots are being lit with blue rich metal halide already and would see now advantage (spectrally) going with LEDs. What they could do though is not make them so bloody bright!

Completely agree with placement accuracy of LEDs having the ability to reduce light pollution. It is not unusual to be able to hit the required lighting levels on a road with 30-50% less lumens than an HPS (measured at end of life in both cases). LED lighting is also far more amenable to electronics controls. Turning down streetlights at night does not impact safety as the traffic levels are less and hence not as much light is needed.

As LED efficiency improves, I think you will see a move towards 4000k(ish) as the standard for outdoor LED lighting. 5000K+ is not really justifiable. It does not enhance vision appreciably but contributes to added glare.

Semiman


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## Cataract (Apr 9, 2013)

One city in Quebec has a law against light pollution. Of course, it is also the center of our biggest observatory. I wish this was an international law.

http://www.astrolab-parc-national-m...on_abatement_project.the_astrolab_project.htm


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## TEEJ (Apr 9, 2013)

I was born in NYC. I had been MOSTLY in/near cities my entire life.

BUT - When out west, a great joy was laying on my back in the desert...looking up at the night sky, like a velvet dome, covering from horizon to horizon. The dome was dotted with stars, millions and millions of them, stars I had never seen before, and which added a depth and breadth to the universe as I knew it. I was maybe 10 years old, but, I still remember it with awe.

It also made me realize what I'm missing back in civilization; the universe.


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## SemiMan (Apr 10, 2013)

Cataract said:


> One city in Quebec has a law against light pollution. Of course, it is also the center of our biggest observatory. I wish this was an international law.
> 
> http://www.astrolab-parc-national-m...on_abatement_project.the_astrolab_project.htm




Believe it or not, many cities have "laws" that should contribute to reduced light pollution. The issue is lack of adherence and enforcement.

Semiman


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## Cataract (Apr 10, 2013)

SemiMan said:


> Believe it or not, many cities have "laws" that should contribute to reduced light pollution. The issue is lack of adherence and enforcement.
> 
> Semiman



Mostly lack of enforcment IMO. This one city has done it and many people finally realise it is not necessary to have super bright lights to see where they're going. I can't find the news article anymore, but the before and after pictures showed a very obvious difference.


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## SemiMan (Apr 11, 2013)

Cataract said:


> Mostly lack of enforcment IMO. This one city has done it and many people finally realise it is not necessary to have super bright lights to see where they're going. I can't find the news article anymore, but the before and after pictures showed a very obvious difference.



Every day I see new installations around me that I know for a fact do not meet the cities planning guidelines.


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## Cataract (Apr 12, 2013)

SemiMan said:


> Every day I see new installations around me that I know for a fact do not meet the cities planning guidelines.



Yup, and so it is in many many fields. I see things that make me shiver every week and those people are audited by very strict companies. There is still hope on the horizon, but the horizon is not at the same distance for everyone...


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## TEEJ (Apr 12, 2013)

Cataract said:


> Yup, and so it is in many many fields. I see things that make me shiver every week and those people are audited by very strict companies. There is still hope on the horizon, but the horizon is not at the same distance for everyone...



Hmmm, aside from altidude differences, the horizon SHOULD be at the same distance for every one.



And, seriously, you're right it seems.


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## Cataract (Apr 15, 2013)

TEEJ said:


> Hmmm, aside from altidude differences, the horizon SHOULD be at the same distance for every one.
> 
> 
> 
> And, seriously, you're right it seems.




Actually, the east/west horizons get further and further away as you get closer to the equator :geek face:
With altitude, the horizon should seem closer (earlier sunrise and later sunset), but some are stuck in a hole where the sun don't shine 

A few years ago I was far out East where population is pretty scarce and I was being nagged by these little light flashes I could see every few minutes. After observing long enough, I found out what it was: I could see artificial satellites pretty much everywhere. If you can't see those on a clear night, then you are definitely experiencing light pollution.


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## AnAppleSnail (Apr 15, 2013)

Here's that article:

How I beat light pollution in my hometown


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## Cataract (Apr 15, 2013)

That's a different town, not even the same country for that matter, but it's nice to see that someone can make a difference. The case I was talking about was different; it was a request from the observatory to the town hall that got addressed farily quickly. But thanks to you, now we know what to do and it might work for other things than just light pollution... of course, changes would definitely come sooner and faster in small towns than metropolises.


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## LEDAdd1ct (Apr 20, 2013)

I am pretty sure in 2013 (give or take a few decades) most of humanity, congregated in or around major metropolitan areas,
does not know what real "night" and "dark" look and feel like.

The few times I've been lucky enough to experience it,
it is as if the darkness in the air actually touches your skin and has a real, fleshy presence.

Turning on _any_ flashlight in that atmosphere makes you feel like a powerful being.

I have a feeling that if more CPF'ers lived in rural areas, they would be satisfied with far less lumens.

Here are some links on urbanization; I feel fairly confident in stating that areas of higher population density will have proportionately (or even exponentially) more light pollution:

Link One

Link Two

Link Three

Link Four (PDF)


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## kaichu dento (Apr 20, 2013)

Nice post - reminds me of spending time outside at night during the winter with the Japanese years ago. 

After telling them we'd continue on as soon as they were ready, they would just stand there in the darkness, not making a sound. 
Took a while for one of them to finally explain that since most of them were from the Tokyo area, absolute dark and absolute 
silence were new sensations for them and they were trying to absorb as much as they could while they had the chance.


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## mvyrmnd (Apr 20, 2013)

LEDAdd1ct said:


> Turning on _any_ flashlight in that atmosphere makes you feel like a powerful being.
> 
> I have a feeling that if more CPF'ers lived in rural areas, they would be satisfied with far less lumens.



This is exactly why I want MORE lumens. Smashing through the complete darkness of a empty paddock, or bushland, with a multi-thousand lumen light is even more empowering than in a city.


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## LEDAdd1ct (Apr 21, 2013)

I can see that perspective as well, and would even enjoy it.

I wonder if we could add a poll to this thread:

"Do you consider yourself to live in an area with heavy light pollution?"


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## SemiMan (Apr 23, 2013)

LEDAdd1ct said:


> I can see that perspective as well, and would even enjoy it.
> 
> I wonder if we could add a poll to this thread:
> 
> "Do you consider yourself to live in an area with heavy light pollution?"




I do ... but fortunately there is a very large lake directly south of me that cuts the potential lights in my area by 50% 

Semiman


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## Slazmo (Apr 23, 2013)

I was outside the other night trying to catch a glimpse of the meteor shower we were to be able to see on the eastern seaboard of Australia on the 21st April...

Problem was the lights from Surfers Paradise was so bad that night that we couldn't see anything other than some of the brightest stars in the sky, light pollution is a major thing these days ruins the most beautiful backdrop to our lives the night sky with its stars and heavenly bodies!


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## N8N (Apr 27, 2013)

Unfortunately, because people suck, light pollution is going to continue to be a problem...

my parents live fairly in the middle of nowhere, but it's difficult to enjoy the darkness even at their place because there's a big HPS light on the pole barn near the house to light up the yard/driveway. Reason being that burglaries are not uncommon even in that area. So most people have big lights on their property, even if they are much farther apart than in a city.


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## sticktodrum (Apr 27, 2013)

I live in NYC, but only work in Manhattan. I live in Queens and it's really not that bad around my area. A few street lights, and they're pretty sparse. Going out to Long Island is nice because there are many towns with very little light. After meeting and befriending a few astrophysics majors in my undergraduate years, I would go out to Montauk and observe the skies. Good stuff.


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## kuna (May 14, 2013)

I also live just around 17 miles from NYC and the light pollution is bad. It really is amazing when you get to a darker sky and you can see how many stars there really are. I remember seeing the milky way for the first time a few years ago and being amazed


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## LEDAdd1ct (Jun 17, 2013)

I thought forty to fifty miles outside NYC was good until I _really_ saw dark skies out west. The whole eastern seaboard glows at night.


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## Sigurthr (Jul 14, 2013)

I live out in the country, but I have a "major" city 20mi to the northeast and the state's largest prison system 15mi to the southeast of me. Normally I'm rural enough to see a sky full of stars when all the exterior lights are off, but if there is any cloud cover at all the light pollution from the prison and city just obscures huge sections of sky. Myself, and most of my "neighbors" (one to two miles away at closest) have sodium lamps to help cut down the stray light. It IS easier to see the stars in a blue/green deficient ambience. I personally have a 55W LPS lamp doing all my exterior security lighting, but the bulbs and ballasts are hard to find so it isn't exactly a catching trend. I have a LED spotlight for right in front of the house where we park that we only keep on when we leave or are expecting company, and it is amazing how much it cuts down stellar visibility.


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