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Atlas of Worldwide Light Pollution
mgarraha writes: "Researchers at the University of Padua and NOAA have analyzed DMSP data to produce a new atlas
of night sky brightness due to artificial lighting. Previous maps only showed the distribution of light sources. Their
paper
will appear in the Monthly Notices of the Royal Astronomical Society. Here is an AP article."
The reason for this divide is the large pool of relatively warm water to the south -- the Gulf of Mexico. Frontal systems crossing the midsection of the continent are relatively moisture-starved until they can tap the much higher precipitable waters in the atmosphere influenced by the Gulf.
In spite of the govt's effort to populate the drylands of the West in the late 19th century, Ma Nature played her winning card with the Dust Bowl of the 1930s. Now, even though the high plains are intensively farmed once again, it's only because of powerful electric pumps which will deplete most of the Ogallala aquifer in the next 20-50 years. After that, the left hand side of that line will be really dark.
In other news, astrophysicists have announced that they now know what all that dark matter is: it's stupidity.
I couldn't agree with you more. When I was a young teen, I lived in the suburbs of Philadelphia. Because I had such and interest in astronomy, they allowed me purchase my first telescope, a 4 1/4 inch reflector from Edmund Scientific. I could go out into my back yard on almost any given night and have a clear sky (weather permitting, of course) and see most of the stellar sights. It was amazing and awe inspiring. We'd go to farmlands of Lancaster and it was just like you could fall off the Earth.
Today, I live even further in the "country" and can see almost nothing. Yes, there are a few nights when I can see the stars, those are the nights of power failures. It's very sad. As real-estate developers continue to build larger, more luxurious homes with overzealous lighting in already heavily populated areas or buy out the precious open space, the situation just keeps getting worse.
In the 60's and 70's, the sky was still pretty amazing. No wonder we wanted to go into space. Now, we look up and it's not quite so awe inspiring...sorta like a polluted beach or something. "Who wants to go there???" we ask.
People wonder what the big fuss is all about. But, as the previous poster stated, it truly is a humbling experience to look up and see the heavens as our forefathers did hundreds, if not thousands, of years ago.
In some respects, the Californian's are lucky. With the rolling blackouts, maybe they'll get a glimpse to see what we are all missing.
this "light pollution" is just a problem made up by do-gooders.
Well, it's mostly caused by wasted light. Most of the light that actually comes out of a street fixture goes straight up into the air, where it does no one any good. That's a tremendous amount of wasted energy. The light bulb's efficiency sucks already. But now we have to make it put out more light just to see what we're doing on the ground. When headlights (which on EVERY SUV in the country are TOO BRIGHT and pointed up TOO HIGH) shine into a driver's eyes, he has more trouble seeing the road. That's actually dangerous. There's a type of headlight that's made in Europe, (my car aficianado friends tell me) which focuses a far sharper cone on the road and works about a thousand times better. They are not permitted in the US because the DOT standard is "good enough."
All in all, light pollution, besides ruining the night sky for astronomers and amateurs alike, is a pretty important topic. Our energy costs could go down . . . oh yeah. I forgot, that would hurt the oil com^H^H^H^H^H^H^Heconomy.
One day I feel I'm ahead of the wheel / the next it's rolling over me / I can get back on / I can get back on
Compare light to population and no one should wonder why the US is the biggest polluter in the world. Put together the light intensity of China, India, and Indonesia, and you've got half the population of the world, yet they still put off less light than the NorthEast corridor of the US. That's 3,000,000,000 people to 60,000,000.
According to this article, an SUV owner spends an extra $100-$250 per month compared to a regular car in just operating costs on top of the extra cost of the vehicle. It would be better to put this in a retirement fund. Considering that 85% of these vehicles are never used for the conditions they are designed for, that really is a waste. All for ego.
the good ground has been paved over by suicidal maniacs
It's a map of light sources, and shows some really interesting structures. The Nile is much brighter than the rest of Egypt, the central U.S. is a grid of cities, and there's a railroad stretching across Russia to the Pacific Ocean.
A small version of the image was an astronomy picture of the day last November (http://antwrp.gsfc.nasa.gov/apod/ap001127.html), and a larger version of the image is also available (http://antwrp.gsfc.nasa.gov/apod/image/0011/earth lights_dmsp_big.jpg). There's a short writeup at http://earthobservatory.nasa.gov/Study/Lights/.
Gates' Law: Every 18 months, the speed of software halves.
If we are seeing so much artificial lighting from space, then it says something about the lighting used. If the light sources were only pointing their light towards the grounds, using shrouds to avoid upward distribution of light, then we should see a darker night view. Also, any light source that can be seen from space is probably also using more energy than necessary. Being environmental friendly is not always a question of finding an alternative, but simply using what we already have in a smarter way.
Jumpstart the tartan drive.
Disclaimer; I'm an amateur astronomer and a member of the Int'l Dark Sky Association. The thing that drives the light pollution activists most nuts is that this is nearly all waste. The majority of lights, and nearly all of the lights that you see in situations like this, are badly designed lighting fixtures that spill much (sometimes more than half) of their light uselessly into the sky. People put in lights to illuminate buildings and roadways, then they use crappy fixtures that send more light into your eyes than onto the intended target. Bad lighting is sometimes worse than no lighting at all. I've certainly driven down roads where I could see better after I get out of the lighted street area, because of the glare from the lights directly in my eyes. I've also seen really bad flood lamp security lighting where a robber could walk right up to the house and not be seen, because again, the lamps are glaring in your eyes so bad you can't see in the shadows. It's this kind of thing that gets me going. That, and people that are so scared of the boogeyman that they have to have several thousand watts of lights on their property up all night long.
driving up auto insurance rates by making yourselves more vulnerable to injury
Wow. Let me tell you a story about four fucking wheel drive. About ten years ago, I was driving through Kansas in November or so. Doing 70 mph, we drove onto an inch-thick sheet of ice, rather suddenly. The wind was chilling the road, and all the melting snow suddenly became solid. The car in front of me (just a car) started fishtailing. I tapped my brake ever so lightly, not yet realizing my peril, and I was fishtailing too. Well the car in front of me lost control and went off the right side of the road, flipped upside down, blew his front and rear windows out, and landed sitting upright. Screaming kids, stunned drivers. I went off to the left, but managed to keep the car upright, and safely stopped. The 18-wheel truck behind us managed to come to a safe stop as well.
After I talked to the driver of the car, and made sure they were all alive, we drove to the next town to call the police (this was before every pinhead had a cell phone in his back pocket) and for the next hundred miles I counted a four-wheel-drive vehicle tumbled over on the side of the road every three miles. I only saw one or two regular-sized cars. Almost without exception, the people who misjudged their driving abilities, their speed, and their car's traction, were driving a hopped-up SUV or light truck of one kind or another. I saw maybe three or four regular cars. The rest of us, not having this blind belief in the indestructibility of our vehicles, drove slowly and cautiously. But the SUV assholes roared past us all, and a good number of them ended up inverted in a ditch. So DON'T TELL ME about how your SUV is so fucking safe. I laughed as I drove past some of those people. I laughed the fuck out loud. You are buying the DELUSION of safety with an SUV.
My original post had nothing to do with the fitness of these cars. I just made a note that the lights were pointed higher than they needed to be. I will point out that I have yet to be blinded by the lights of a bus or 18-wheel truck. I think because they're correctly configured. It's as if the SUV designers sat down in a smaller car, right in front of the SUV, and designed the lights so that they could not help but annoy the driver in front of them.
People wouldn't hate SUV's so much if their designers and owners didn't make such a point of being arrogant about them. I can't tell you how I long to go up to a Jeep and paint in big bold letters on the back windshield: "No, it's a penis thing, and sadly, I do understand."
One day I feel I'm ahead of the wheel / the next it's rolling over me / I can get back on / I can get back on
You're just one more person with an agenda claiming unrelated benefits for compliance ... After reading this story, almost everyone will forget about it, because it's really not very important.
Perhaps you should stay more in tune with current events. Like the power crisis in California. Using less energy is not an unrelated but a pretty direct benefit.
The folks up in Clagary thought so, as you can read here. They expect significant savings in energy by changing to full cutoff light fixtures.
A similar law recently passed in Connecticut and another is awaiting the governer's signature in New York.
Light pollution also takes its toll on the environment in more subtle ways then wasted energy.
From a story at ABCNews.com:
"Darkness for Health
Scientists have now discovered that only when it's really dark can your body produce the hormone called melatonin. Melatonin fights diseases, including breast and prostate cancer. "It turns off the cancer cells from growing," says Joan Roberts, a photo biologist. But if there's even a little light around your bed at night, your melatonin production switches off. "So there may be this natural way that Mother Nature has given us, that is, dark night to keep certain cancers under control," Roberts says. Even watching TV turns on other immune system hormones that should be active only in daytime. They get depleted, and you're more likely to get a cold. Nature needs darkness, too. The immune systems of animals grow weak if there's artificial light at night."
Not getting cancer seems like a pretty significant benefit.
Light pollution also has adverse effects on migrating birds and plant life (the plants can't track the natural light curve and don't properly prepare for winter).
Interested readers my wish to check out the International Dark-Sky Association for more info on light pollution and its effects.
Steve M
You didn't have to go to so much trouble just to nag me.
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A couple of points:
(a) seeing the universe laid out for real is awe-inspiring and more than a little humbling. I think that if more people were to see the real night sky more often, there'd be a significant attitude change. When you realize just how insignificant and impermanent we humans are, the bullshit in life isn't so important any more.
(b) street lights actually increase crime rates. No one wants to wander the streets in the dark, it's a bugger to break into a house when you can't see what you're doing, and it's difficult to be unseen when your flashlight turns out to be the brightest thing in the neighbourhood.
(c) if you really want to be impressed, take up backpacking and head into the mountains. There are some remote areas that make the normal "real" view from out-of-town look about as cheesy as the out-of-town view makes the in-town view look!
(d) in particular, aim to be in the mountains during a meteor shower. Ye godz!
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Don't like it? Respond with words, not karma.
This is due to other atmospheric hazes -- in Chicago there's all sorts of moisture in the air and other aerosols that reflect the light pollution back to you when you're looking up, thus making it harder for you to see stars. But under clean air there can be a huge amount of light pollution around you and it won't affect the sky brightness very much at all.
I've seen the Milky Way from the city of Tucson, one of those very bright spots, but never from my home of St. Louis despite the fact that they're both hopelessly light polluted, and this is why.
I think an atlas of the worldwide pollution would be much more interesting. Especially in a time when the Kyoto Treaty is dangling. Pretor
I live in the murky Eastern United States and if I can see a half a dozen stars from my backyard it's a good night. A few years ago I spent six weeks at White Sands Missile Range in New Mexico and one night several members of my team drove out to a remote corner of the site to take a picture of one of those comets that was big news in 1996 - I forget it's name. I thought the comet would be the high point of the night. It wasn't. Folks, when you are laying on your back looking up at the whole Milky Way splayed out above you, and you can really SEE that thing streching across the sky, it is a truly life humbling experience you will always remember. You almost think you could fall off the planet into the void. There is one hell of a lot more to see out there than a screen resolution of 800x600 pixels will ever show and it is worth the effort to get to dark skies to see it.