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cosmoquest
2012-May-16, 06:09 PM
We have had several folks ask us about how and if dark skies awareness and protection fits into CosmoQuest.

The simplest answer is that without dark skies there is no astronomy from the ground. We are deeply passionate about partnering with people who are in the trenches both tracking the loss of darkness (eg with GLOBE at Night) and working to create legislation to enact lighting restrictions that save energy, keep people safe, and also keep the stars visible in the sky.

We'll be working to out together a resources page for dark skies. What do you want us to add and to share?

How can we help those of you already in the trenches?

Cheers,
Pamela

kmasterdo
2012-May-17, 09:36 AM
The International Dark-Sky Association (http://www.darksky.org/) has lots of information on this subject.

kmasterdo
2012-May-26, 10:30 AM
The British Astronomical Association's Campaign for Dark Skies (http://www.britastro.org/dark-skies/)

ANUBISGALAXY
2012-Jul-08, 06:17 AM
Hi Peeps,
I have been so fed up with street lights blocking my view of the sky with sodium glare that I have made a simple device to put them out! Recipe:- Take one baked bean can and fix a super bright LED inside to the base along with battery, switch etc. Turn baked bean tin upside down and fix to a long pole, I use one of those plastic lengths that you can buy from a gardening suppliers. Our Street lights here in the U K are switched off by a light sensitive device on top of the street light. So now when I want to use my telescopes, I first position my baked-bean-light-can-on-a-stick-patented-device over the light sensitive device on the street light and hey presto, darkness. We live in the countryside so there are only one or two street lights that effect my viewing, or should I say used to effect my viewing! Another way to effect darkness from an annoying street light is to blow said street light to bits with a shotgun but I don't advise it personally as it is a bit naughty, makes a lot of noise and the local council would probably jail you for murdering a defenseless street light, but before my little invention, I had often contemplated shooting the one that bathed my back garden with that horrible orange glow of sodium street lighting. Hope this helps or at least makes you smile,
Jack Llewelyn.

Jerry
2012-Jul-13, 12:18 AM
Here here! Eight years ago, I moved from an urban area to a high mountain desert platau, and became reaquainted with the Milky Way of my youth. Over the next seven years, urban sprawl encrouched upon my dark sky and dispite some pleadings with the county commission, there was no way to prevent the spoilage. I should have tried harder.

I now live in another urban area with no chance to escape the pollution (in my Leaf); so if you are in a position to effect change or limit pollution, buy all means do so. it is easy, and not expensive if the necessary ground rules are laid out up front; but once polluted with light, the sky is almost impossible to reclaim.

natattack
2012-Jul-13, 04:07 AM
Here in Ottawa, I've discovered that there's a small street that decided to turn off its lights for about a month this summer and I know they've had at least one sidewalk party with several scopes out. Unfortunately the streetlight on the corner was not turned off so there was some glare off to the north, but I still think it's an interesting idea. It still doesn't beat heading out to the country of course :)

Parallel Universes
2012-Jul-13, 06:19 AM
Aren't street lights supposed to light up dangerous sections of road in rural areas? I'm lucky. None out my way. The stars look like you can reach out and touch them. Street lighting reduces crime and car accidents so I'm not sure politicking on the issue is a worthwhile activity. Lets be honest, astronomy is not a priority with politicians. Most people have no interest in the subject so its not a vote grabber. Ensuring the skies are clear is of interest to amateur astronomers so they can further human knowledge now and long into the future. Councils don't think beyond the next local election.

astropaz
2012-Jul-14, 01:03 AM
Aren't street lights supposed to light up dangerous sections of road in rural areas? I'm lucky. None out my way. The stars look like you can reach out and touch them. Street lighting reduces crime and car accidents so I'm not sure politicking on the issue is a worthwhile activity. Lets be honest, astronomy is not a priority with politicians. Most people have no interest in the subject so its not a vote grabber. Ensuring the skies are clear is of interest to amateur astronomers so they can further human knowledge now and long into the future. Councils don't think beyond the next local election.

This is just the type of post that I imagine this section of the forum was born for, to educate people.

Some of what you have just said are just popular catch phrases with no real bearing on real life, but it sounds good and the public lap it up. Heaven forbid we don't want criminals everywhere and cars running off the road every 5 minutes.

There have been numerous studies that show when street lighting is turned off there is an actual reduction of crime. This link has quite a number of links in it which goes over both sides of the argument.
http://www.britastro.org/dark-skies/crime.html

And I don't buy dangerous sections of roads either, I can tell you from personal experience that lighting on a rural road has no effect on the outcomes of terrible accidents. And the vast majority of accidents on roads have nothing to do with lighting conditions, cars come equipped with sufficient lighting.

Your right however that it's not a vote grabber, but maybe tax payer funds being uselessly wasted is?

John Jaksich
2012-Jul-19, 04:05 PM
This is just the type of post that I imagine this section of the forum was born for, to educate people.

Some of what you have just said are just popular catch phrases with no real bearing on real life, but it sounds good and the public lap it up. Heaven forbid we don't want criminals everywhere and cars running off the road every 5 minutes.

There have been numerous studies that show when street lighting is turned off there is an actual reduction of crime. This link has quite a number of links in it which goes over both sides of the argument.
http://www.britastro.org/dark-skies/crime.html

And I don't buy dangerous sections of roads either, I can tell you from personal experience that lighting on a rural road has no effect on the outcomes of terrible accidents. And the vast majority of accidents on roads have nothing to do with lighting conditions, cars come equipped with sufficient lighting.

Your right however that it's not a vote grabber, but maybe tax payer funds being uselessly wasted is?


I tend to agree--but I happened to notice a handful of LED street lights in the vicinity of my neighborhood--very cool and there is seems to be some evidence that LEDs cover more area. I happen to be of the opinion that there should an Astronomy Awareness incorporated into more school curricula.

astropaz
2012-Jul-23, 08:49 AM
Astronomy awareness would always be a good thing to bring to students, a good way to inform them of the facts and myths as well.

I'm not sold on the LED light implimentation, infact for astronomy I think it can only be a bad thing. The white light given off plays with our rods and cones in such a way that it's going to make observing DSOs a big challenge and the other major downside to this lighting is it's unfilterable.

Still it looks as if we are stuck with it and I guess there are positives in that it's a greener energy and the sky above the lighting appears darker as they seemingly do reduce light spill.
I guess it's good as long as your not near them. I certainly don't want them anywhere near me.

John Jaksich
2012-Jul-23, 02:25 PM
Astronomy awareness would always be a good thing to bring to students, a good way to inform them of the facts and myths as well.

I'm not sold on the LED light implimentation, infact for astronomy I think it can only be a bad thing. The white light given off plays with our rods and cones in such a way that it's going to make observing DSOs a big challenge and the other major downside to this lighting is it's unfilterable.

Still it looks as if we are stuck with it and I guess there are positives in that it's a greener energy and the sky above the lighting appears darker as they seemingly do reduce light spill.
I guess it's good as long as your not near them. I certainly don't want them anywhere near me.


In the late 1970s and beyond Mercury Vapor lights were replaced with Sodium Vapor lights because of the amount of light coverage they provided. It had been documented that "women" were less likely to face assault from an "unknown assailant" if the Sodium Vapor lights were installed. Since that time---further studies (as astronomers may attest) have shown how bad twin lines (in Sodium "spectrum") have affected "seeing" of the sky.

The LEDs are supposedly better for amount of area that they cover --as well as not affecting that part of our vision (the twin Sodium lines).

filrabat
2012-Jul-23, 09:03 PM
Still it looks as if we are stuck with it and I guess there are positives in that it's a greener energy and the sky above the lighting appears darker as they seemingly do reduce light spill.

Greener practices along with greener energy producers is even better. Plus a little financial incentive always helps.

Sell them on the fact that light just shining up in the sky out in suburbia, or simply reflected off the street serves no productive purpose. Therefore, there is no compelling public interest in having light escape into the sky. Therefore you can shine less light and get more brightness for the megawatts -- meaning more brighness for the buck. What are the power company customers (including municipal governments) getting in return for light shined up in the sky?

Solution? A good one is as low-tech as you can get - put metal shades on the street lights, interior mirrors. This way, the light can go to where it's intended to go, rather than just being scattered all over the place. It also better illuminates a smaller area. This means we can spend much less money (and fossil fuels) to light the same area. Add that to already existing "greener bulbs" and you get not only $ savings, but reduced global warming in the decades ahead.

Of course there are instances when light scattered all over the next half-mile or so DOES serve a compelling public interest (i.e. around prisons, tall buildings [to prevent aircraft from crashing into them], and no doubt other instances that have to be taken on a case-by-case basis). Still, this should bring back some of the darkness to the night sky AND save money for electricity consumers (the latter is so in theory at least).

On the legal activism end of things, we can urge the courts to curb an unreasonable excess of activities of property owners with regard to their night lighting. Bright lights shining into windows a block away may very well qualify as a legally-defined Nuisance. Nuisances have been known to decrease the value of surrounding properties, after all.

astropaz
2012-Jul-24, 08:03 AM
In the late 1970s and beyond Mercury Vapor lights were replaced with Sodium Vapor lights because of the amount of light coverage they provided. It had been documented that "women" were less likely to face assault from an "unknown assailant" if the Sodium Vapor lights were installed. Since that time---further studies (as astronomers may attest) have shown how bad twin lines (in Sodium "spectrum") have affected "seeing" of the sky.

The LEDs are supposedly better for amount of area that they cover --as well as not affecting that part of our vision (the twin Sodium lines).

The thing is though these LEDs are actually much worse astronomically and physiologically speaking than the sodium lights. The LEDs emit a much broader spectra than the sodium ones with the ultimate end result being that there is essentially no wavelength left that is unpolluted and it's more damaging to the observer than moonlight.
There is a better explainatione here, just scroll down to the second last page.
http://www.darkskiesawareness.org/files/PTarticle_Lighting&Astronomy.pdf
And again you can't filter out these lights, an LP filter makes short work of the orange sodium lights but you cannot filter out the broader LEDs.

As for the physiological effects the wavelengths of LED lighting have been shown to intefere with melatonin production in humans and animals and will mess with our circadian rythms.
http://physics.fau.edu/observatory/lightpol-astro.html#LEDsAndUs
http://docs.darksky.org/Reports/IDA_Blue-Rich_Light_White_Paper051710.pdf

The only thing these lights have going for them are they are cheaper to run and can be more easily directed to where the light is needed.

I agree with all that Filrabat said, the hard part is to get local authority to implement these kind of common sense changes like shielding without having to push the for it over 18 months.
The best option especially if they are going to continue with the LEDs to to have a switch off and dimming after a certain time.
Sure there are some areas that lighting would be required but for the most part it would be a good solution.