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don't know if its been posted before and if i am correct posting this here but i found a great light pollution site.

it's got a map of the uk (european link scroll to bottom of page) and you can zoom in and place a marker where you live.

it will shows you how light polluted your area is. not sure if they update it though.

sorry if it's been posted before or if i have posted in the wrong place (mod move if you like) http://www.need-less.org.uk/ have fun.

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That is a useful link, thank's for sharing, it shows me a much darker site quite close to where I live, I might try it out in a month or so,

doesn't matter if it's only slightly darker it will be better than traveling long distance, I haven't seen this link before and as I said it's a

very useful tool.

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IMHO, seriously badly designed website. No one is going to read all that bright white text on a black back ground or all the orange text on a greyish back ground.

The opening textual paragraph reminds me of something from when Win98 first made an appearance.

Great idea and one that is close to all our hearts so ++++ but the website is detrimental to the cause!

In today's world, they have to hit it within the opening 4 space/return bars.

Don"t get me wrong, I whole heartedly agree with the idea, ...

but,

NEED-LESS-ANIMATIONS being linked to even more animations is a most certain shot in the foot.

My conclusion, good idea, poorly executed website.

Others will most certainly have thoughts.

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According to the simulator I should not be able to see a single star, it manages to have where I live on it.

However I can stand at my front door and see Herculese Plough, Cassiopeia, Auriga. I can see M13 and the double cluster and quite a lot of other things.

When Orion returns both it and the Pleiades will be easily observable.

Still cannot get a simple light pollution map to display, I do have 2 others bookmarked.

If need-less want you to be able to see what the levels are then a nice simple single click on one link should be prominent - it isn't. It should be a large text prominent title and link. The OP tries to describe where it is hidden, when really it should stand out.

I also find that a number of these are based on the population/size of a place and the distance from the population centre. One observing location I use is universally determined as poor, but it isn't when you actually get there. Pretty good viewing site in realty. Also conveniently close.

West of Cambridge gets classed as poor, but the reality is otherwise.

I can see one road that is "polluted" but there are no lights on the road and believe me when the sun goes down it is dark, I occasionally have stopped in a layby along it to look at the milky way - it may not be staggeringly bright but it can be seen.

Edited by ronin
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According to the simulator I should not be able to see a single star, it manages to have where I live on it.

However I can stand at my front door and see Herculese Plough, Cassiopeia, Auriga. I can see M13 and the double cluster and quite a lot of other things.

When Orion returns both it and the Pleiades will be easily observable.

Still cannot get a simple light pollution map to display, I do have 2 others bookmarked.

If need-less want you to be able to see what the levels are then a nice simple single click on one link should be prominent - it isn't. It should be a large text prominent title and link. The OP tries to describe where it is hidden, when really it should stand out.

I also find that a number of these are based on the population/size of a place and the distance from the population centre. One observing location I use is universally determined as poor, but it isn't when you actually get there. Pretty good viewing site in realty. Also conveniently close.

West of Cambridge gets classed as poor, but the reality is otherwise.

I can see one road that is "polluted" but there are no lights on the road and believe me when the sun goes down it is dark, I occasionally have stopped in a layby along it to look at the milky way - it may not be staggeringly bright but it can be seen.

Needless is funny, light polluted areas are usually around a full magnitude worse than what they actually are but the dark site locations are usually a full magnitude better (this is comparing their NELM's to my SQM readings).

It is a simulation though and a pretty rough one at that but at least it points us in the right direction. :)

Edited by Mike73
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yeah i'm not sure how up to date they are but as mike73 said it points use in the right direction.  thanks for posting laser. if anyone has anymore LP maps please post more the merrier. 

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Needless is funny, light polluted areas are usually around a full magnitude worse than what they actually are but the dark site locations are usually a full magnitude better (this is comparing their NELM's to my SQM readings).

It is a simulation though and a pretty rough one at that but at least it points us in the right direction. :)

Mike, I know what you mean but that just drives me nuts.

Means that it is an estimate based on population and then there is a bias one way or another.

Maybe just my approach but if they are a body concerned with light pollution then they should have accurate and reasonably non-biased data presented. Otherwise I cannot trust whatever they say, also I cannot use what they present.

On every LP map Cambridge is appauling, averge calculated LP means you should be wearing sun glasses at night to avoid the brightness. But the IoA hold observing nights if they can weekly and you can look at most of the available clusters and nebula if you can track them down.

I have sort of given up on light pollution, lets face it it is not going to disappear. Minimising is good, however even that will still wash 95% of the sky out. I simply accept the fact that I can observe at home to the best I can manage, or I drive a few miles. The realisation of this keeps the blood pressure down.

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A few things to consider with these maps, which are simulations based usually on either population or roads;

Different types of lights have hugely different effects on sky brightness at different distances. For example the terribly designed low-pressure sodium lamps that grace our country tend to spill lots of light horizontally. An effect called forward scattering tends to keep this light going horizontally and so it pollutes over large distances. LED lamps and other full cut-off lights only contribute light reflected by the ground, this pollutes on a much more local scale.

The different light scattering effects are also wavelength dependent, so low-pressure sodium orange is scattered differently to the blue-rich white light of LEDs.

The surrounding environment will also have a big effect. Lights in crowded cities will have a lot of horizontal light blocked by buildings for example.

So all in all it's very difficult to predict based on population/road data alone.

The best way to produce a good map would be to actually survey the sky brightness from the ground at different locations. I know of a few such attempts in Italy, but nothing much in the UK.

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don't know if its been posted before and if i am correct posting this here but i found a great light pollution site.

it's got a map of the uk (european link scroll to bottom of page) and you can zoom in and place a marker where you live.

it will shows you how light polluted your area is. not sure if they update it though.

sorry if it's been posted before or if i have posted in the wrong place (mod move if you like) http://www.need-less.org.uk/ have fun.

I love this. I'd be happier if i could enter my exact location here in Ireland. 

Edited by LukeSkywatcher
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how up to date are these maps laser, any idea. thanks

Not very up to date. The Avex map is a simulation based on populations and not actual light pollution levels. For instance our hamlet in Wales is shown as a blue dot- indicating the presence of maybe a few street lights- when in fact the nearest ones are 3 miles away at least!! 

Take the output with a pinch of salt- though it's good for getting the a general idea of light pollution in the area. There is no substitute for a night time recce. Avex won't show stuff like farm floodlights, floodlit rural churches and golfing ranges- all of which are quite capable of wrecking a pristine night sky for miles around!!

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Not very up to date. The Avex map is a simulation based on populations and not actual light pollution levels. For instance our hamlet in Wales is shown as a blue dot- indicating the presence of maybe a few street lights- when in fact the nearest ones are 3 miles away at least!! 

Take the output with a pinch of salt- though it's good for getting the a general idea of light pollution in the area. There is no substitute for a night time recce. Avex won't show stuff like farm floodlights, floodlit rural churches and golfing ranges- all of which are quite capable of wrecking a pristine night sky for miles around!!

thanks

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This site

http://www.blue-marble.de/nightlights/2012

Gives an actual view from space, so is perhaps a more accurate reflection, but it is a bit low res and lacks topographic detail.

I find the Avex site the best of all.

I love this link! For those of us in different parts of the world it's overlaid on google maps. Just toggle map-night. I found an easy to go to site 20 minutes away (circled are). Looks quite dark-Jackpost-37593-0-18508300-1405136639_thumb.j

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