Is artificial light poisoning the planet?

If you want a low-light suburb, check out Irvine, CA on the eastside. Sometimes it's so dark at night, it's scary.

I don’t remember the name but I read a book years ago that was set in a future where humans live in dense cities with everything in between returned to wilderness. I always thought it was a really compelling idea if it were possible.

You'd still have to drive quite a way out of the cities in most places, suburbs or not. The sky glow is noticeable for miles in places with any humidity.

Dense cities tends to be much brighter than suburbs. I’ve lived on a street with bright LED streetlights and even with blinds down bedrooms was uncomfortably bright at night affecting quality of sleep. Now I live in a place resembling American suburbs and enjoy relatively darkness at night.

Every now and then someone posts a photograph of the milkyway galaxy with all its colors and glories during a new moon. It's really frustrating to see most of the top comments calling out that it only looks so pretty because of exposure.

In reality if you manage to get to one of the few places left on earth that are truly dark sky places and you catch it during a new moon, the spectacular lights are really not that far off

Unfortunately the vast majority of internet denizens today have never truly experienced a dark sky during a new moon. An experience that just 200 years ago almost every human has had

I remember that when the Starlink satellites first went up and people complained they were too visible, Starlink agreed to make future ones less so. I don't know why they didn't do that to begin with, maybe the metal is shiny by default and it's an extra cost to make it matte? Maybe it's about heat, since a matte object will absorb more from light? At any rate we're in dire need of some regulation around satellite visibility before we lose more of our night sky... oh, and flying drone billboards need to be banned before they catch on.

Whereas I find nothing pleasant about my night-time drives through the suburbs of Bellevue. I spend the entire drive paranoid that someone's going to cross the street, and that I won't even see them until they are right in front of me.

Rain, darkness, tree cover, incredibly bright oncoming headlights, poor street lighting, and enough-of-a-walking-culture-that-people-might-be-walking-at-night is a great combination.

I'm just up the road in Flagstaff and the dark skies are absolutely one of my favorite parts of living here. Darkness is an underrated addition to quality of life.

Cars are usually equipped with headlights. ;)

On a more serious note, it’s pretty common for UK roads to lack street lights. Particularly in more rural areas. The majority of my drive home from work is unlit.

> Do people walking on foot carry torches?

At night, if there is insufficient moonlight? Yes of course. Street lights only exist in urban areas, if you're walking anywhere else in the world at night, a flashlight seems like a logical choice.

> Do people walking on foot carry torches?

It depends. If there's a full moon out, I often walk without a light. It's wonderful. Otherwise, I use a headlamp.

> Doesn't this cause issues?

No. I think the main effect is that people finish their walks, bike rides, and so forth before dark. Obviously that's impossible for much of the year for people who work 9 to 5, but given the demographics of this community—small business owners with flexible schedules and retirees—it works for most. In particular, there is one woman from a nearby street who walks past my office window every afternoon: in the winter she walks by at 3, and in the summers she walks by around 6 with her husband.

> getting lost

I don't think this is a realistic concern for those with smart phones. Moreover, the hilly topography and lack of cycles in the road network (barring one) make it very easy to remain oriented.

> Do people walking on foot carry torches?

I find a flashlight and a small pocket knife are essential every day carry. It's a quality of life issue for me, I want to be able to examine something at any time of day, plus street lights are intermittent and I walk a lot. I live in Oakland, a major city, but still insist on turning on a flashlight when I cross the street. People don't pay enough attention.

I walk through my neighborhood at night, and some houses have streetside lights, but most do not. I always bring a flashlight but typically don't use it. I do teach my kids they have to be very careful of cars, because they are too short to be seen.

A safety reflector or other high-visibility clothing is a passive method for sending light back at the driver.

https://en.wikipedia.org/wiki/Safety_reflector

Fortunately, no[1]. I live in Tucson AZ, and it's wonderful. We are the home of https://www.darksky.org/

You excluded crime from your comment, but I want to say that anecdotally, places where there are street lights are where the street crime happens.

[1] https://thefifthestate.com.au/innovation/lighting-innovation...

Losing the Dark - Flat Screen Version: https://www.youtube.com/watch?v=dd82jaztFIo

Similarly, the installation of public lightening by Colbert in the XVIIIth in Paris, lowered criminality by an order of magnitude.

It also enabled women rights, since, with the ability to somewhat walk securely at night or in the early morning, comes the ability to go to the factory and work somewhere else than in the house.

I appreciate how important it was in the past, but in the era of inexpensive and powerful LED flashlights, streetlights do seem rather redundant and wasteful.

These days we'd tap into the cell phone network/radio waves to track pedestrians. It's the modern safety reflector or high-visibility clothing.

Are you not carrying your phone with you? Well, "it would be a shame if something happened to you."

It’s LA, no one walks.

Another approach is to have personal lighting. I regularly attend an event in one of the darker parts of Colorado where it's considered common courtesy to have a glowy something or other attached to you. There can be collisions even between pedestrians. Nobody gets hurt but it's awkward when it happens so you start to appreciate the extra cues.

Flashlights? Reflectors? We don't need streetlights illuminating empty roads all night.

Street lights can also aggravate the problem of safety. Unfortunately most cities seem to believe that more lumens = more safety. But often times this creates more stark dark spots and makes it harder for our eyes to adjust to them

What would really improve safety the most is having more, warmer, weaker lights. One city in the UK ended up taking down their streetlights after some attacks and replacing them with christmas lights strewn across some city trees.

Not only did it look nicer, end up costing less, and was less damaging to the local ecosystem, but it also likely made the area much safer

I'm fond of warm, yellow hues for indoor spaces. If I were forced to choose a color for outdoor lighting, I would go for the same. However, white vs. yellow has already played out in some areas: https://www.latimes.com/archives/la-xpm-1993-09-30-mn-40657-...

This is only half true. bluer LED lights only need half as much light to get the same visibility.

I don't agree that these are the only possible states. I think we can still have artificial light for an extra 8 hours, but we can be more responsible with with how we use it. At the moment it seems typical in many places to install lighting without much thought about how it effects others, or how that light finds its way into the sky.

At the micro scale, why does my neighbour have two flood lights in their back yard? They actually have the narrowest lot in the city; it's something like 21 feet across. In effect it's similar to having these lights in _my_ back yard. The neighbour past them also has a large, bright light installed and facing directly at my yard perhaps 30 feet away. Other neighbours nearby have similar lights which don't interfere with my yard so obviously, but certainly inhibit seeing the night sky. The result is that there's one corner of my yard where a telescope isn't flooded with light (even with a shroud), and I'm limited to looking into the sky past trees and buildings. I still enjoy it, but I could have so much more clarity and visible sky without those lights shining in my yard.

At the macro scale, the highways and urban areas around me make little effort to direct light down; it's extremely diffuse in all directions, illuminating the sky directly rather than indirectly. There are thousands of bright signs, street lights, and other sources of light which no one has made an effort to reflect their light downward. Studies show that doing so makes a substantial impact on light pollution, and it should by all means be the law to reduce this pollution like any other, but where I live it appears to be on no one's minds.

I'd also make the case that seeing the night sky is an important activity for human beings, similar to "touching grass" or going on a walk in the woods. It's a primordial thing, part of countless cultures' stories, a source of deep and long-lived questions about our origins (religious or otherwise), and practically an engine of human discovery via sheer inspiration. Do we really want to live without a connection to that? Is it good for our kids to grow up rarely if ever seeing the arms of the Milky Way, Pleiades' glowing gas and dust, or the same of the Orion Nebula?

These asterisms and other cosmic formations are stunning spectacles we're constantly deprived of. They reveal the wonder of the universe and spur our minds. If you live in a polluted city and rarely get to leave though, you're out of luck. How many young bright minds are never hooked by this sense of awe and wonder, and thus, never reach for the sciences? How many people of lower socioeconomic status will literally never witness something as fundamental as the clear night sky?

Similar to being on a mountain in winter at 7am as the sun rises, seeing the sun shine and glow along the ice and snow, seeing an expanse of glaciers, mountains, forest, and a huge open sky – these things are becoming privileges, but they were once integral experiences and part of our connection to the universe and the earth from which we're all made. If you have no religion, at least you could have that.

I don't think everyone needs to have these things to be whole or that they're subhuman for having missed out. I just think so many people would benefit greatly from it, both tangibly and intangibly. The more we disconnect from nature, the more it seems to harm us. The clear night sky is akin to looking into our past, the stellar nursery of where we were all created.

That may not be as practical or useful as 8 hours of artificial light, but I don't care much about more light when it only means another 8 hours of grinding at things I don't feel enriched by or connected with. There needs to be a balance in there somewhere.

Other forms of pollution are worse, but light pollution does harm animals. When baby turtles hatch they instinctively look for bright lights lower on the horizon and go towards it. Because naturally, that will be the moon reflecting off the ocean. Bright beachfront buildings are even brighter than the reflection of the moon leading them to wander away from the ocean

Moths and frogs are also attracted to lights. Migratory birds rely on seasonal cues such as changes in the amount of light. The OP article also mentions in the intro that it is reducing bat populations in areas.

The owner of my building has installed flood lights that are on all night and effectively remove any darkness from the outside. The main reason given was for safety, despite there never being a safety issue, and trying to convince them that the opposite is true has been difficult, to say the least.

Could you link them? That's an interesting conclusion. Is there any correlation drawn, or even speculation as to the cause for this? Perhaps criminals need some light as flashlights draw too much attention?

Genuinely curious to see the source of this statement. I was always under the impression that more light is safer.

Motion sensing lights outside my house certainly did nothing to improve safety for me, for the barest extra convenience of not having to remember to turn the porch light on before leaving when expecting to come back after dark.

They were likely detrimental, especially when considering the extra paranoia when I'm sitting there stoned trying to watch a movie and the light keeps ticking on outside. I got fed up with it and unscrewed the bulbs enough to not turn on, and so far my landlord hasn't complained about me doing so.

Criminals like to be able to see what they are doing as much as anyone else.

We experimented with cutting streetlight power at night where I live.

After six months of higher crime rates, we switched them back on.

So I suspect its a variable thing, based on location and existence of other lighting.

I miss the sodium lamps.

They were being transitioned out during my university years. First year all the lights on campus were that cool, single frequency yellow, by senior year there was just one, stuck in a lonely corner of campus, buzzing it's familiar call. I think the single emission spectra was a big part of the appeal. The complete lack of color left things somewhat eerie, but in a distinctly nonthreatening way. Just an alien peace.

I gave that some thought too. However, if “rhodopsin becomes superfluous” then it won’t be a survival/reproduction factor.