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Earth Space

Help Map Global Light Pollution, By Starlight 148

Posted by timothy from the can-you-see-below-the-belt? dept.
Kilrah_il writes "Light pollution is a big problem these days, affecting not only astronomers and wild life, but also everyone else because of wasted energy. GLOBE at Night aims to raise awareness by urging people to go outside and find out how much light pollution there is in their area. 'The campaign is easy and fun to do. First, you match the appearance of the constellation Orion in the first campaign (and Leo or Crux in the second campaign) with simple star maps of progressively fainter stars found. Then you submit your measurements, including the date, time, and location of your comparison. After all the campaign's observations are submitted, the project's organizers release a map of light-pollution levels worldwide.'"
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Help Map Global Light Pollution, By Starlight More

Help Map Global Light Pollution, By Starlight

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  • I'll help (Score:5, Funny)

    by MrEricSir ( 398214 ) on Tuesday March 22, 2011 @10:08PM (#35582330) Homepage

    I'm going to go out at night with a big flashlight and find those gosh darn light polluters.

  • What are these "stars" of which you speak? (Score:3)

    by overshoot ( 39700 ) on Tuesday March 22, 2011 @10:19PM (#35582394)
    I live in Phoenix, thank you, and 20 miles from the middle of town on the opposite side of a mountain range I can see my way around the house at night without lights -- and with the blinds closed.

    • Re: (Score:3)

      by afidel ( 530433 )
      Drive another 20 miles away from the city and you will see more stars than 90+% of the first world's population has seen in their life. One of the most amazing things I have experienced in my life is stargazing in the desert southwest.

      • Drive another 20 miles away from the city and you will see more stars than 90+% of the first world's population has seen in their life.

        20 miles further out and I'm still in Wal-Mart territory (Cave Creek.)

        Now, 90 miles further out and Phoenix is just a glow on the horizon. About like sunset, really -- you can actually see Orion on a clear night. To see the Milky Way, though, you have to be farther than that. Like Show Low or Pinetop. Once I'm on the White Mountain Apache reservation the sky starts to be really worthwhile, and it only takes a four-hour drive.

    • I can do the same. But it's probably because all my electronic devices have LEDs telling me that they're _almost_ off.

    • Re: (Score:2)

      by elrous0 ( 869638 ) *

      As a soldier from the future, sent back to protect John Connor's second cousin from attack by an obsolete Terminator 320 model, I must say that's the one thing I miss about the apocalyptic future. You people just can't appreciate the beauty of a sky totally free of light pollution, but unfortunately filled with Hunter-Killers.

    • I live on the side of a city-facing mountain in Las Vegas...if I leave my blinds open at night, it's like sleeping in the middle of a fully-lit Walmart. First thing I did when I moved here several years back was sell my telescope.

    • Re: (Score:2)

      by Quirkz ( 1206400 )
      I feel your pain. I used to live in Chicago, and regularly joked that "the airplanes are really bright tonight" because that was often the only thing you could see.

      Luckily I now live 10 minutes outside of a small mountain town. The trees and mountains limit what I can see around the horizon, but overhead I can pick out the milky way, even if a couple of neighbors in my cul-de-sac leave their front lights on.

  • Seriously, the light pollution around DFW is so bad I can't see much more than Orion and the Big Dipper. During last night's super moon, the faintest star of the Big Dipper was hard to see. Couldn't make out the Little Dipper at all.

    • Stars are typically hard to see during a full moon, let alone the super moon which was 30% brighter.
    • Um, not only was it a full moon, but it was hazy outside. I'm in DFW too and have quite a few ruined full-moon pics to demonstrate the haze...

      • I was pretty happy with the pictures I got of the moon. It was the 4 second exposure of a landing plane that showed me how bad light pollution was. The sky looked black to me but the image was light streaks on an orange background.

        • I was pretty happy with the pictures I got of the moon. It was the 4 second exposure of a landing plane that showed me how bad light pollution was. The sky looked black to me but the image was light streaks on an orange background.

          I'm just curious, what set up did you use? The best shots I got were at 1/640 of a second at f/5.6 with the ISO setting at 100. I haven't had a chance to get a better lens, so I used the 28-135 that came with the camera at full zoom.

          • I used a Canon T2i, 75-300mm II @300mm. I don't remember the exposure settings exactly but with a fairly low ISO I was shooting 1/1000 - 1/2000s and f/5.6.

  • Huh? (Score:1)

    by Kid Zero ( 4866 )

    Last time I was at our local (ish) observatory, they had a light pollution map. Is this new?

  • Hope people pay attention to clouds (Score:5, Funny)

    by Hoi Polloi ( 522990 ) on Tuesday March 22, 2011 @10:28PM (#35582444) Journal

    "It was raining and the pollution was terrible, couldn't even see Rigel."

  • I live in Seattle. We can't see the sky through the clouds.

    • So you can't even see Sol then. That's pretty bad ;)

    • At least you get a great view of the Pacific Nebula.

    • For my first 4 months at Ft. Lewis I thought Mt. Rainier was some mythical place found only in pictures. Then, one nice clear day, there it was! And then it was gone again.

      Kinda makes you wanna drown your sorrows in some locally-produced meth and start the grunge scene.

  • but also everyone else because of wasted energy.

    I use solar-powered security lights which turn on at night . This helps with safety and security, and the benefits far outweight the cost.

    The article is misleading, and referring to night-time illumination as "pollution" is derogatory and disingenuous. If you feel light except starlight is unwanted, then get a parcel of sufficient forested property, and don't cut down your trees, so you can take a walk far enough from civilization to see what you want.

    • Re: (Score:1)

      by Anonymous Coward

      I think they're fine with your security lights as long as they point down. Any ray that points up doesn't help with safety and security, and is light pollution.

    • Re:Light pollution != Energy waste (Score:5, Insightful)

      by kimvette ( 919543 ) on Tuesday March 22, 2011 @11:17PM (#35582708) Homepage Journal

      The problem isn't nighttime illumination.

      The problem is poorly designed nighttime illumination. Why are parking lot lights often aimed at a 30* angle, emitting much or most of their light skyward? Why are huge flood lights used to illuminate flags and signs, when a small spotlight would be more environmentally friendly and more efficient? Why are most street lamps still convex rather than concave or flat? Sure, even if nighttime lighting were properly designed as a general rule some light would be scattered by the atmosphere, and some would be reflected but if you ever visit a gated community with proper lighting you can see that traffic areas (walkways, streets, etc) are well lit and very safe, but the sky is still quite dark.

      • Re: (Score:1)

        by mysidia ( 191772 )

        but if you ever visit a gated community with proper lighting you can see that traffic areas (walkways, streets, etc) are well lit and very safe, but the sky is still quite dark.

        Because gated communities pay the high-priced lighting design experts, due to wanting it to be aesthetically perfect, and have the money to pay for that? Lights pointed to the sky tend to cause glare, which is not all that aesthetically pleasant in a nice gated community area.

        Why are parking lot lights often aimed at a 30* angle

        • Re: (Score:2)

          by Isaac-1 ( 233099 )

          The problem is people feel safer if they can see the source of the light rather than just the effects.

          • Which ironically makes them less safe, because of the increased shadow area and because their eyes adjust to the light source, making those shadows even darker...

          • Re: (Score:1)

            by mysidia ( 191772 )

            The problem is people feel safer if they can see the source of the light rather than just the effects.

            So piggyback a proper light source they cannot see with an independent, low-intensity "feel good" light source that they can see of one wavelength of a high-energy frequency that will be attenuated by the atmosphere over a short distance?

        • but if you ever visit a gated community with proper lighting you can see that traffic areas (walkways, streets, etc) are well lit and very safe, but the sky is still quite dark.

          Because gated communities pay the high-priced lighting design experts, due to wanting it to be aesthetically perfect, and have the money to pay for that?

          The OP used a poor example by citing a wealthy community (though an available one). He could of cited the entire city of Tucson which has used such lights since 1972. Using non-light-polluting fixtures (which can also be described as "more efficient fixtures") doesn't require high priced "lighting design experts", it only requires that you buy the fixtures.

          Lights pointed to the sky tend to cause glare, which is not all that aesthetically pleasant in a nice gated community area.

          And everywhere else also. Kinda the point. Why should every one else have a glare blighted sky, at considerable electrical cost?

          Why are parking lot lights often aimed at a 30* angle, emitting much or most of their light skyward?

          Probably something about using as few lights as possible. If they pointed them straight down, a lot more lights would be required to achieve the same illumination. If they put them closer to the ground, the lighting would be easily blocked, or people would have to contend with the lights being distracting.

          Probably not. The energy

      • I am guilty of engineering a retrofit of lighting at a oil terminal to replace the long, yellow, low-pressure sodium lighting bulbs (400 watts) with 1500 watt HID lights.

        The old light system was dim, with poor color rendition. The oil terminal could not do any work in the yard at night and it was difficult to detect a problem. (it was dark).

        I went about in replacing all of the low pressure sodium lights with new 1500 watt, HID heads on the poles. Not being the one who was actually doing the wiring and never

    • Don't forget the grue issue.

      • Re: (Score:1)

        by mysidia ( 191772 )

        Don't forget the grue issue.

        Yes... light is important for warding off Grue infestations.

        For this purpose a backup generator is recommended, as Grue can get indoors easily.

        Another technique is to get a Wumpus, because Wumpus' eat grue.

        The problem with that strategy though, is Wumpus eat neighbors too... so you better have them in fenced-in yards, and be sure to pack plenty of spare arrows.

    • Re: (Score:2)

      by sjames ( 1099 )

      A lot of the "safety" lighting is actually harmful to safety. It creates a bright area to keep people's eyes from dark adapting and dark shaded areas you can't see into at all. That's where the mugger sits and waits for a lone pedestrian. Meanwhile, the local delinquents like to hang out under lights as well. Turn them off and they'll go elsewhere.

      BTW, I did *NOT* choose to live in a population concentrated civilized area. When I moved here, the skies were pitch black at night. You slobs who moved in and we

  • So dark sometimes, you can't see the wall you just walked into!
    Need more LED's on my PC's...

  • City time (Score:2, Insightful)

    by markdavis ( 642305 )

    >"find out how much light pollution there is in their area."

    Tons! But I live in a city and there isn't much I can do about it. Mostly poorly designed street lights. Then there are those neighbors that think their property is so much better with a megawatt of flood lights all over. Ug.

    But I would GLADLY put up with even more light pollution if it meant less NOISE pollution from damn modified motorcycles, leaf blowers, barking dogs, horns, sirens, and ESPECIALLY those "boom box cars" projecting their d

  • You know who doesn't have a light pollution problem?

    North Korea!

    (Did I misunderstand the whole Godwin thing?)

  • Whatever (Score:3)

    by Antisyzygy ( 1495469 ) on Tuesday March 22, 2011 @11:07PM (#35582660)
    I'd like to see a more quantitative study. Why not try to measure the ambient light in these environments? Then we can compare it to the light received in a telescope from various stars in the same local. Most people intuitively know that light pollution makes it so you cannot see the stars easily in brighter cities, why waste the time of multiple people to explain something obvious. Its better to actually get real and scientific data you can use for something worthwhile, like illumination correction, optimal location of observatories, etc.

    • Most people do not own light meters, and most that do have meters that only measure down to .1 or .01 lux. Besides, ground-level light is not a good measurement of what the sky looks like.

    • There are plenty of those maps already, and telescopes are placed at some of these locations. A high resolution map in a city is meaningless except on a dry windy cloudless night that has blown all particulate matter away, so maybe then the scatter from lights will be low, so there will be local dark spots, where you see the stars well. I doubt the scatter is ever that low. So I think you are correct, there is no value here, besides aesthetic.
    • You are definitely correct that this is a very bad way to actually measure the light pollution, but that isn't the point.  By getting more people involved they are getting the word out.  When more people are aware of what is going on then by convention the more likely it will be that architects, light manufactures, city planners, etc. will implement projects differently.

  • you can almost see the stars...

  • at night.

    Driving East towards Houston in the middle of the night is like driving into the sunrise even if the sun sat behind you not but a couple of hours ago. Considering I grew up on desert side of the state I know what the sky is supposed to look like at night, and I know what it doesn't look like here, it's just a glow. Yeah, this whole region could use some light shading.

    • Re: (Score:3)

      by afidel ( 530433 )
      Head north, my buddy lives in the hill country between San Antonio and Austin and I was able to see the milkyway from his ranch.

  • go outside and find out how much light pollution there is in their area

    Tried that, but it was so dark I couldn't see a damn thing.

  • This subject is clearly driven by astronomers with a desire to view the night sky. The issue of wasted energy seems only to be mentioned to gather support. This is clear in the first article which suggests using a 'shade' to make street lamps more efficient. A reflector is necessary if you want to get more useful energy out, as an opaque shade will just make your lamp housing hotter. I believe that modern designs do include reflectors now.

    The biggest issue being overlooked here seems to be what happens

    • Re:Extra-black asphalt please (Score:4, Interesting)

      by Iskender ( 1040286 ) on Wednesday March 23, 2011 @03:24AM (#35583546)

      This subject is clearly driven by astronomers with a desire to view the night sky. The issue of wasted energy seems only to be mentioned to gather support. This is clear in the first article which suggests using a 'shade' to make street lamps more efficient. A reflector is necessary if you want to get more useful energy out, as an opaque shade will just make your lamp housing hotter. I believe that modern designs do include reflectors now.

      It doesn't really matter why astronomers say what they say. What matters is if it's true. And there is no doubt that illuminating the sky directly is a waste of electricity and therefore money. If they advocate less than stellar solutions then the answer is to get better solutions, not to ignore the whole light pollution issue.

      The biggest issue being overlooked here seems to be what happens to the light that shines down as intended. This light reflects off things sending light upwards regardless of the lamp design. If you look at the aerial motor race photograph linked below you will notice that most of the light seems to be coming from the track itself, not the lights.
      http://www.craigfergusonimages.com/2009/11/aerial-f1-singapore-at-night-by-wong-kin-leong/ [craigfergusonimages.com]

      I don't think anyone is overlooking that. If you look, I doubt you can find many who say "We should eliminate ALL light pollution from urban areas". That's not happening, and everyone knows it. Astronomers accept the lesser bad of reflected light, and strive towards that rather than some improbable utopia.

      There's another thing too: light pollution is rarely created above light fixtures (which is where the picture is taken from), but to the side. Streetlights mostly light pollute in the near horizontal, meaning they tend to light pollute some distance away from themselves. If the camera actually was in the line of sight of the light sources (like people on the ground, or the sky when floodlights point at it) then the picture would be so full of camera flare that it wouldn't look even half as pretty.

      To sum up: reflected light is a problem, but it's nothing at all like what we have now, so people who care would be happy to deal with it instead.

    • It's not just astronomers, although for optical astronomers it's an issue. (we radioastronomers wory more about microwaves, mobile phones, electric fences and such).

      It's mainly biologists, ecologists and such, who see the large effect on the plants and wildlife.

  • When light is directed downward at the ground some of that light is reflected upward again. Otherwise we could not see what is on the ground. How do you stop light being reflected by the ground? People want to be able to see when walking the streets after dark, play sports at night, etc.

    There are some lights that need improvement but great strides have been made. The bad lights can not be found by people describing ambient light.

    Another issue is that when people look at the sky they have generally just left

    • When light is directed downward at the ground some of that light is reflected upward again. Otherwise we could not see what is on the ground. How do you stop light being reflected by the ground?

      You don't, and that's okay. The reflectivity of stuff on the ground is on average fairly low (like 10% or less), whereas for directly emitted photons it is 100%. One doesn't need to entirely eliminate every part of a problem to deal with the major part of the problem.

  • You can see a real-time light polution map here http://www.die.net/earth/?zoom=1 [die.net]

  • North Korea FTW [globalsecurity.org].

  • The way we currently use outside nighttime illumination is very wasteful. Large powerful unshielded lamps end up throwing light where is ISN'T needed or wanted wasting power and putting more CO2 into the air. What's even worse is that by having this extra light spilling out we create glare that blinds us by killing off our sensitive night time vision. The human eye is well night adapted. Our iris can open to over 7mm (in younger people) and we have sensitive cells scattered about our retina that activat

  • I'm from Las Vegas. Stars? I'm not familiar with this Orion. Is he one of the Elvis Impersonators?

  • Seriously, this strikes me as an ideal app for a starter project. Build an app that is designed to record a pix, the time, and the location of pix and send it to a server. That server can then make decent approximations of what night lights are. THink in terms of wunderground and their personal weather stations.
  • Funny how no one has posted anything about the International Dark Sky Association [darksky.org] yet.

    They have guidelines for selecting lights etc. here [darksky.org].

  • Core to this project would seem to be relatively precise lat/long data. However, if you take a spin through their 2011 map, you can find a submission located in the middle of the north Atlantic. Having been there myself, I can tell you that as long as the moon isn't out, you should expect all magnitude 8 submissions...

    But no, this is a magnitude 3 submission... the same as if you were a few miles from a city. Can't be valid... then when I take a look at the "more information" of this submission, it say

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