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@Ranger, 3000K and LED does not help,

@encad should let the IDA know. It was their recommendation not mine.

Although LEDs reduce carbon dioxide emissions, if you don't use the right ones, they could make dark skies worse. Blue light is very disruptive to humans and animals. The International Dark Sky Association has the details on how to use dimmer lights and LEDs and nothing above 3000K. Also, don't illuminate where you don't need to: http://darksky.org/lighting/lighting-basics/.

There are communities, parks, reserves, and other categories. See International Dark Sky Places.

I personally would prefer to see a streetlight that's smart enough to know when it's not needed. See: http://darksky.org/.

Perhaps not in the way depicted here, but yes indeed, light can be a form of pollution.
http://darksky.org/light-pollu...

Thanks for that link to NoiseOFF. That is a very interesting site. Combined them with the efforts of the International Dark-Sky Association, and the world would be a better place.

A simple (but unfortunately short) list is provided at the following site. Rumor has it these parks actually enforce rules. If you show up with a flashlifght, you will be escorted off the premises. Support your nearest dark sky state park!

http://www.darksky.org/night-s...

http://www.darksky.org/

The http://www.darksky.org/ has several resources. Better yet, become a member.

I am sure for both amateur and professional astronomers that this would result in horrible seeing conditions as well. Please look at http://www.darksky.org/. Dark night time skies are hard enough to find due to light pollution even now. Better than global warming I guess!

More info over at www.darksky.org . It costs a lot of money/oil to keep all those lights on. Is it worth it? Have your children seen the milky way?

They have guidelines for selecting lights etc. here.

They have guidelines for selecting lights etc. here.

A note on geography: upstate New York is not NYC. It's the rest of the state, some of it is far enough away from the light polution that there is a chance see stars. There's small chance of seeing even the moon, let alone the milkyway in any major US city.

It's a shame. There's no good reason we have to spend good money shining light up into the sky, rather than keeping it on the ground where we paid for it to be. In a lot of areas a good case could be made to put the streetlights on timers and cut out after 11pm or midnight.

We are paying *lots* of money for oil to light up the sky at night (which helps no one). In the USA, this is mostly imported oil. So, in the current economy there will be a lot of pressure to stop wasting money and oil, and stop producing greenhouse gasses, etc.

A. I live in a city of 750,000 - Just to give you an idea of scope, the glow of the city is very prominent when outside the city. In fact, from a couple of vantage points at least about 50 KM away you can still make out the lit towers in the city center.

B. When is a plant a weed? When you don't want it where it is. Light pollution is light which is not serving a purpose. That city glow I mention above is not doing anything to benefit anyone, it's light going up into space where it really can't help.

Light pollution is also wasteful from a financial standpoint. Full cut off lighting directs the majority of light from the lighting element to the desired location meaning you can use lower wattage bulbs, or fewer bulbs, to achieve the same level of ground lighting. In addition full cut off lighting reduces road glare which increases driver safety in night driving.

The International Dark Sky Association has some good resources on the subject. Based on the source you may want to keep a grain of salt handy, but I don't see much bias in their statements. http://www.darksky.org/

It's a pity few even realize what a problem light pollution is.

Indeed. Galileo made many of his observations from the city of Venice. Back then, you could still see the stars from a city center. Now, even the outer suburbs are pretty degraded.

If you care about changing this (and a lot can be done), join the International Dark-Sky Association.

Tucson has been working on this for years to protect various local observatories. It's also the home to the international dark sky association: http://www.darksky.org/mc/page.do

They have a city ordinance making it illegal to have a light shining upwards - all lights (street lights, security lights, porch lights, etc) have to have a reflector. It's apparently pretty easy to police - bare bulbs are highly visible from the police helicopter.

Seems to be kinda silly to spend your lighting budget trying to illuminate the universe anyway.

And not just the professional astronomers. There are many amateur astronomers or would-be amateurs, if only they could see some more stars. Light pollution affects more than just astronomers.

See http://www.darksky.org/ for guidelines for new lighting installations.

Most places in US are now grossly over-lit with poorly designed fixtures. Good lighting design produces less glare, puts the light where we need it, saves energy, and protects helpless animals. (There, don't you feel better.)
Also, note that astronomers prefer the monochromatic lights, because they can block that wavelength easily with a filter at the telescope.

How does that impact light pollution? If they're going to replace all the streetlights, perhaps they can take the initiative to make sure the light doesn't leech upwards into the night sky and start New York down the road to Dark Sies status.

Yes it is a matter of safety, but take a look at the variety of fixtures available. In some towns there is widespread use of street light fixtures where there is NO horizontal face in the light's bezel; it's all down-facing, directing the light to the ground. There is some reflection from the ground to the sky of course (that is unavoidable) but in those areas the sky is much darker than it is in towns where conventional street lamps with the convex half-globes are used, with a lot of horizontal and even upward light emission.

Likewise for home lighting - why should any light be visible from ABOVE the lamp's install location? The light should be directed to the ground where it is needed, not up into the sky, not lighting the trees, and so forth. All it does is crap up the sky so we don't even know what the milky way looks like any more. Where I grew up I thought the sky was dark (it was probably somewhere between Class 4 and class 3, but then I've read about class 2 and class 1 sky and that the milky way is actually quite visible - not just as a faint lighted haze but with definite features, similar to what one sees in time-lapse photography. It's really sad that we never get to see those features. I'd rather look up and see the gorgeous galaxy we live in than to see an orangy glow at night.

How is sky 'darkness' rated?

http://www.newyorker.com/reporting/2007/08/20/070820fa_fact_owen
http://x.astrogeek.org/articles/article.php?article_id=1

How should light pollution be controlled?

http://www.darksky.org/mc/page.do?sitePageId=58881

Light Pollution International Dark-Sky Association Starry Night Lights

I'm surprised not to see any mention of the International Dark-Sky Association; this is what they are all about.

From http://www.darksky.org/about/ :

Goals
      1. Stop the adverse effects of light pollution on dark skies, including
                    * Energy waste and the air and water pollution caused by energy waste
                    * Harm to human health
                    * Harm to nocturnal wildlife and ecosystems
                    * Reduced safety and security
                    * Reduced visibility at night
                    * Poor nighttime ambience
      2. Raise awareness about light pollution, its adverse effects, and its solutions
      3. Educate everyone, everywhere, about the values of quality outdoor lighting
      4. Help stop other threats to our view of the universe, such as radio frequency interference (RFI) and space debris.

There are a bunch of very interesting articles on how less exterior lighting gives better visibility, roughly speaking because floodlights don't really light up everything and end up blinding you more than general darkness with point illumination.

Yeah, flagstaff is a great example of what you can do to cut down on light pollution. The International Dark Sky Association is a good resource for people who are interested.

Does anyone know of a database dark sites, or how I could find a place near me?

Try Dark Sky. Click on Dark Sky Finder version 3 and input your coordinates. It will show you the dark sky sites closest to you.

Thanks, I may check it out later.

unfortunately I live in a brightly lit city and know of no place where I can go to shoot the stars

This tool will tell you about the nearest dark skies: The Dark Sky Finder. The tough part is finding a place to park. This tool will just drop you in the middle of nowhere. It might be easier just to find a star party near where you live.

Actually, we can improve lighting on earth, save energy, AND improve our view of the cosmos. Our existing nighttime lighting is enormously wasteful. Good lighting design lets you "see where you're going", without blinding you with glare, or destroying your night vision with excessive light. Please visit the International Dark Sky Association which has been working to solve this problem for decades. First, realize that lights that shine up into the sky are helping no one. Any electricity used to illuminate the sky is wasteful and causes light pollution. Properly shielded lights direct light at the ground where it is helpful, instead of at the sky.

Tucson AZ has been fighting light pollution for more than 20 years. This isn't exactly a new fight. That said, it's gaining momentum. In part thanks to the IDA. That having been said, this won't be won until the general population sees light pollution as a bad thing. We aren't there yet but with more general public articles there are chances that light pollution becomes as well known as air and water pollution.

For what it's worth, some estimate that there are about 700,000 amateur astronomers in the US. It's not a huge number. But it's much bigger than the just a few geeks that some would make you think.

It's a good fight and it starts at home, you can do your part by turning off the exterior lights of your house when you don't need them. With 2009 the international year of astronomy, if you help now, maybe we all will get a better view of the night sky to celebrate the 400 years of telescope observing of the night sky.

You've hit an important point here. William McDonough http://www.mcdonough.com/writings/extravagant_gest ure.htm argues that renewables allow us to live abundantly. I find his critisism of the eco-efficiency movement as lacking anything that can motivate people quite interesting. Run you christmas lights and your neighbor's too.

But, be sure they're aimed down please. I don't like light pollution: http://www.darksky.org/

Disclosure: I sell solar power (reserve a system at my home page).

Those lights are fishers. They use very bright light to attract fish or shrimp to the surface. There's a lot more of this around japan on this picture. They appear to be clustered around richer fishing grounds.

what I have always wondered is how about the long term financial stability of the corporations. It is quite obvious that new emission laws and a mandatory reduction in fossil fuel usage will be expensive in the short term. But haven't they done studies of the consequences of global warming to their companies? If global warming is a reality is quite possible that the consequences of it are catastrophic. I would think that drastic climate change will cause a breakdown of the economic structures we now enjoy. Some corporations might be able to adjust but not all of them will. Those corporations that can't adapt will suffer tremendous loses and maybe even bankrupcy.

Assuming this as true, I can think of few likely explanations for the current corporate attitude:

• They haven't considered the long term consequences of global warming
• They think they can adapt or profit from global warming
• They trust their research as good one and think Global warming is a farce

Honestly I have a hard time believing that the last 100 years of human development have had no consequences on the climate. when I see this http://www.darksky.org/images/satelite/ida_asp_02. gif Picture, and then think that only 100 or so years ago most of that map was almost completly black. Although this is picture have very little to do with climate change(on the surface at least), it clearly shows that we can have a huge impact on earth. Weather is too late or not, we are about to find out.

How much money do we spend, how much air pollution, acid rain, and global warming do we create so that we can light up the bellies of birds? It is possible to have development that does not rob us of our heritage and right to enjoy the night sky. International Dark Sky Association

It's good that there are starting to be light pollution ordinances. The International Dark-Sky Association works to reduce light pollution and increase the efficacy of night time lighting. I've lived in areas where the street lights are turned off after a certain hour. That is really nice. Though it sucks having to stay up so late just in order to see the stars properly.

At least with telecommuting there is a definite, tangible energy savings, unlike questionable tactics such as extending Daylight Saving Time.

It would make so much more sense for an "Energy Policy Act" from the US government to provide assistance (via tax breaks or assistance) to companies to lessen the weekly energy consumption of their employees.

Allow companies to let their employees telecommute one day a week, for example. Or, help companies move to a 4 day week (10 hour work day, not every employee would have the same day "off").

These are simple actions with an instant benefit of 20% savings in energy.

Beyond that, the government could have linked federal dollars to adoption of "Dark Sky" ordinances at the state and local level. This would shave a few more percent off the US energy budget by getting rid of over-lighting, trespass lighting (light that unnecessarily spills over to a different property), and useless lighting (light that doesn't actually light anything - ie, heads out to space).

cursing those maniacs in the early 21st century responsible for cleaning it up and weep for the days where we couldn't see the stars around large cities.

Not being able to see the stars has nothing to do with particulate pollution, rather it has to do with those horrible sodium (the orange ones) lamps that started popping up in the 70's. I wish to God we would stop lighting up the night.

Yes they can and they have. Light pollution can blot out all but the moon and occasionally Venus. At the minimum, light intended for use on the ground, but used to blot out the stars is waste of money and resources.

You can, however, take it back. See the International Dark Sky Association for more options.

Is it too early to consider Open Sky as an alternative?

There is also a Dark Sky alternative. Most inhabitants of urban areas in the U.S. and other areas, though have never actually seen a night sky, especially the younger ones. Limiting the light shining up into the night would allow a view of the stars even in or near urban centers.

With all the talk of being efficient or getting a return on investment, you'd think that at least a few would complain about using good money to light the sky instead of the ground.

A natural consequence of aging is that the retina gradually receives less and less light, due to clouding of the cornea and the inner fluid. It affects nearly everyone. It affects night vision most dramatically, I'm in my mid 30's and really notice my night driving ability going to hell. I remember in my teens being able to drive effortlessly in moonless night rainstorms with poor wiper blades, now I struggle even on clear nights. http://www.darksky.org/infoshts/is156.html So, if it seems like everything was brighter when you were younger, it was, as far as the light that actually made it to your retina was concerned! But it wasn't necessarily because the universe outside of your eye was brighter. I read an estimate (can't find the source) that by our 30's, our retina receives only 50% of the light as it did when we were a child. We don't notice it so much because the brain is remarkably good at compensating and interpolating.

...in my experience means: "Visible to the naked eye of an experienced observer under the age of 40 with good eyesight whose eyes have been dark-adapted for at least half an hour, on a clear night in dry weather with no moon, at time at least three hours after sunset or three hours when the object is at least 40 degrees above the horizon, on a hill with dry air at least a fifty miles from any town with a population of over 2,000 ."

Exactly right. Take back the night. Learn how to curb light pollution at darksky.org.

Doom 3 should be the #1 gaming low of the year.

But... Doom3 contributes to de-illumination, as 1000s of gamers were forced to quench their home-lights each night to have even a vague chance to discern monsters on the gloomy screen. So it supports astronomy, you should be happy!

I've always considered this image to be a hall of shame. The areas lit up the brightest are the ones that are the most wasteful. There's no reason for even a highly developed region to be lit up like that.

Remember the rule, if you can see the actual light bulb, and you're not standing between the light and what it's supposed to be lighting up, it's a crappy fixture and is just wasting energy. The US alone wastes over a billion dollars a year on energy wasted due to bad lighting fixtures.

Go to a home improvement store sometime and try to find a decent exterior light fixture. You can't, they're all crap. People wouldn't hang a bare bulb in their house and think it was pretty, but for some reason they think it's fine outside. I think it's because it's shining AWAY from them, they don't have to look at it.

You can buy decent fixtures, but not at the big box stores, so most people never realize they're buying junk fixtures.

See the International Dark-Sky Association for more info

Light pollution is overlooked by most of the populace, but to us amatuer astronomers it is a royal pain in the ass. I now have to travel 3 hours into the rural sticks to get a glimpse of the Milky Way (I'd have to get on a plane and travel to Africa to enjoy it in its full glory). I'd be willing to bet that half the US population has never even seen the galactic clouds of the Milky Way ... which is a shame because it borders on a religous experience.

Not to sound like Smokey the Bear but please Please do your part in help preventing light pollution and save a little extra in your monthly energy costs in the process. Use motion sensors for your outside security lights and timers for walkway lighting. Blinds and curtains to prevent inside lighting from leaking out into the neighborhood.

You'd be suprised how many backyard astronomers there are!!

More info on the problem:
International Dark Sky Association

Actually this is gives just a rough idea of what light pollution you might experience. If you want to find out more, you can look at the The World Atlas of the Artificial Night Sky Brightness.

If you are in north america, the Clear Sky Clock gives you an quick way to see what light pollution is like on your clock having extracted sections from the atlas. For instance the Montreal clock clock gives this map for Montreal. Clearly not a great location for astronomy.

But the worst, is to realise that this loss of light results in actual light pollution since much of this electricity has been generated with fossil fuels which produces the CO, NOX, CO2 and eventually SMOG.

The International Dark-Sky Association has a locator for finding the places near your location in the US with least light pollution.

Well, the sunlight may be dimming but we are more than making up for it with the amount of light that we are putting out at night.

Take a look at some of the satellite images here.

If you have wake up before dawn this week for work or school, take a pair of binoculars outside and scan the eastern horizon. You might see Comet Bradfield. The comet, which had a close encounter with the sun on April 17th, is now emerging from the sun's glare. Although it's too dim to see with the unaided eye, at least for most people, by all accounts Comet Bradfield is a beautiful sight through binoculars, its long tail stretching 10 degrees above the rosy glow of the rising sun.