LEDs’ potential to save our night skies

https://spectrum.ieee.org/led-light-pollution

by defrost • 2 days ago

245 183 2 days ago

spectrum.ieee.org

dgellow• 2 days ago

Thorp notes that modern CCTV cameras are “pretty great” even at low-light levels, while harsh light makes it hard for both human eyes and digital sensors to see.

That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system”

WarmWash• 2 days ago

Their prime audience for change are governments...

swiftcoder2• 2 days ago

That’s a weird thing to include. That sounds like an argument _for_ more aggressive lights. I didn’t expect to see a “think of the surveillance system”

One of the biggest excuses for ultra-bright streetlights is crime prevention (usually shortly followed by CCTV). I'm not really sure why we continue to indulge that point of view, but if one is indulging it...

rznicolet• 2 days ago

It's even funnier that, at least around here, one of the biggest crime problems is people stealing copper wiring... from streetlights...

trollbridge5• 2 days ago

The "lights=safety" nonsense shows no sign of coming to an end. Many private residences also install eye-searing levels of lighting outside that they just leave on all night, which is much cheaper to do now thanks to LED technology. There's really no reason for doing it. The idea it deters crime is a long-standing myth (someone analogous to the idea CCTVs deter crime).

Jblx2• 2 days ago

I know we can be all righteous and intellectual on HN. But the article pretty much glosses over the large number of people who are afraid of the dark. Not afraid of crime in the dark. Actual adults who are apparently having a visceral reaction to the dark. What percentage of people is this? What percentage of those would adapt in a positive manner?

mghackerlady• 2 days ago

Even then, couldn't you just use IR cameras with IR lights for illumination. I'm sure that comes with it's own set of issues, but strictly speaking is better for maximising surveillance while minimising human impact

pjl0• 2 days ago

If your goal is to reduce light pollution, addressing/deflecting the concerns of the surveillance state is probably more likely to get you to that goal than ignoring the concerns entirely or tying yourself to the omnicause

michaelt2• 2 days ago

I once lived in a city that had replaced street lights that cast light in a circle with modernised ones that cast a sharply delimited rectangle of light on the road, and didn't waste light in other directions.

The thing was, the roads of this city were arranged as a footpath, then a grassed area with trees, then the lights, then the roadway. Only after the city had rolled out thousands of these lights did someone notice the footpaths were now much darker. And also the footpaths were quite uneven, due to the trees' roots - a problem the lights had previously been keeping under control.

It's now common, in winter, to see groups jogging on the road.

Rotundo2• 2 days ago

Over here, joggers are frequently wearing headlamps to illuminate their way. Often combined with a light on their back. They can see and can be seen, which is safe.

michaelt2• 2 days ago

There are some fine products on the market compared to a few decades ago, yes. I particularly like the fact rechargeable lights are always at full brightness.

Alas when running in a group, the runner in front of you can not just obstruct your line of sight of the pavement, but also the light of your torch. His retroreflective vest becomes the brightest thing in your view. And he's not happy either; backlit by your torch, he casts a shadow forwards and the road ahead is illuminated everywhere except where he's about to step. And of course the tree-lined pavement, while very beautiful and shaded in the summer, isn't very wide. So you can't always run beside the guy.

My personal 'solution' is not to run fast enough to keep up with the guy ahead of me, giving me a clear view. But you don't win medals with my attitude.

wongarsu2• 2 days ago

Planners forgetting that pedestrians exist is sadly a common occurrence

Finnucane• 2 days ago

Get rid of cars and they'd take down all the lights.

Loic2• 2 days ago

Where I live, we have a small park, 500m away. You need to walk through it if you want to get to the city center from the small neighborhood we live in. To protect the wildlife, the lighting system has presence sensors, so as you walk or bicycle through the park, the way/street lighting turns on, you can walk, and just after you, it turns dark again. Really cool, especially the first time I went through it in the middle of the night.

fhdkweig4• 2 days ago

Those things drive me nuts. There is a walking path that I frequent, and I can't use it at night because they are spaced every 20-30 feet. When I am not under them, they are off and my eyes adjust to the darkness and as I pass under one it flips to full daytime brightness and blinds me. As soon as I walk away from it, everything goes dark again, but my eyes had adjusted to the daytime brightness of the lamps. And I know that in 30 feet, I have to do it again, for the next couple of miles.

Loic2• 2 days ago

The timing and brightness is well adjusted, it feels natural, like a friendly ghost taking care of you.

vel0city• 2 days ago

If it gets used a good bit, I wonder if the on/off cycles are even more impactful to the local wildlife than constant but more optimized lighting was in place.

I know if I was trying to sleep a constant source of light is easier to get used to than a randomly flashing source of light. And for nocturnal animals I'd imagine randomly losing the cover of darkness from time to time is probably a lot more stressful than just avoiding the brighter areas.

I'd be interested in seeing data. I really wonder which is better.

trollbridge5• 2 days ago

Wouldn't it be more reasonable to just expect people who want to walk places in the dead of night to wear a headlamp? They're cheap, easy to recharge, and can be adjusted for various brightness levels.

wongarsu2• 2 days ago

People associate a lack of lighting with crime

I vaguely remember that studies showed that lack of streetlights does not create crime, but the crime that happens anyways prefers badly lit areas. But from a pedestrian's perspective that's not much relief, you'd still avoid those areas. Which is not what a city planner has in mind for a park

fhdkweig4• 2 days ago

I would consider that ideal, but there would always be the fear of a potential negligence lawsuit if someone got hurt or crimed, so the government considers them necessary.

amiga3863• 2 days ago

The problem is not just with people who want to walk places, but people who want to mug/murder/rape those that do.

As an example, in the UK, councils are expected to light commonly-traveled paths, both so path users can see where they're going, and to reduce crime. Unlit paths in city parks are still traversed, and are often a haven for crime.

"Dead of night" isn't the right image. 5PM in winter with clouds (as is typical in the UK) has roughly the same level of natural light as 2AM. People are still coming home from work in conditions where natural light is low enough to lead to accidents and crime.

ninalanyon• 2 days ago

No. Unless you expect everyone to always have those things you will need the street lights anyway so why not make them smart and efficient. This especially applies in northern latitudes where it is dark in the evening even before people leave work.

snarf21• 2 days ago

Serious question: Wouldn't it be better to just have them always be on with red light that is much less disruptive to wildlife?

adrian_b3• 2 days ago

The sodium lamps that were ubiquitous for outdoor lighting before LEDs were quite good from this point of view.

Amber LEDs could provide a similar experience.

redlewel• 2 days ago

Would prefer very dim or red lighting. Also preserves your night vision

michael19992• 2 days ago

We need much better engineering standards if we are going to fix night lighting. A simplistic lux-on-the-ground measure combined with cost minimization produces a few lights, with bare bulbs, up hight, with brutal intensity. These are all things that produce glare directly on the eyeball.

You need much less light on the ground if the eyeball itself has no direct line to the hottest part of the lights. Instead, the night-blindness caused by excessive bare lighting is "fixed" by adding more fill lights for the shadows caused by the first lights. Classic addictive behaviour.

projektfu• 2 days ago

I believe that is what TFA is about.

michael19992• 1 day ago

ctrl-F "standards" - zero results.

The fine article was more about the effects of bad lighting, and the motivation to change. It does not discuss the engineering and insurance standards that generate the bad choices. Perhaps you misread my comment. As long as the standards are left as-is, street engineers are going to keep doing as they are.

lysace2• 2 days ago

The writing style frustrated me immensely.

tl;dr: Cheap cool-white LEDs cut energy but worsened light pollution; warmer, dynamically dimmable LED fixtures/infra fix it but lower costs tend to win.

trollbridge5• 2 days ago

Isn't it standard journalism? Instead of just giving us the conclusion we're supposed to think, they interview various people in the field and quote what those people think, and then let us draw our own conclusions.

lysace2• 2 days ago

No, this is engagement-maxxing style journalism. Complete with the clickbait headline. It also spends almost no time on why the cheaper-but-dumber options win.

(Everything is relative. I expect more from IEEE than the NYP or the Daily Mail, as extreme examples.)

micromacrofoot3• 2 days ago

depending on who you ask the cold lighting also magically stops crime

SuperNinKenDo• 2 days ago

I hate outdoor LED lights so much, I won't be surprised if a couple decades or centuries from now we discover that these things have been doing permanent damage to people's eyes. It's getting harder and more unpleasant to walk at night, I can't see and my eyes legitimately hurt every couple of minutes.

BLKNSLVR• 2 days ago

Does this trigger you: Modern car LED headlights

There doesn't appear to be any standard being followed (anymore?) on brightness or angle or height (or shape). A selection of them are easy to confuse with high beams. Makes driving at night in the rain some kind of epilepsy inducing overwhelm of lights and reflections and lens flare coming from everywhere, reminiscent of the cyberpunk aesthetic.

alt227• 2 days ago

At least in the UK this is being looked into by a government review.

Whether that will amount to anything or not remains to be seen, but at least the issue is being taken seriously.

https://www.bbc.co.uk/news/articles/cn971jlpvvro

trollbridge5• 2 days ago

In the U.S., the DOT sets standards, but they only apply to new vehicles sold. Aftermarket lights can be just about anything. (Some are labelled "not for highway use", as if that prevents them from being used on public roadways.)

Certain types of people seem to think they should install really, really bright LED lights in their car and then aim them right at other driver's eyes. I believe this comes from a mindset where one is unable to put one's self in another person's aspect, or where one simply doesn't care about others.

BoxOfRain• 2 days ago

I miss the night looking like night, the ultra-harsh white LEDs used in street lights are trying to mimic daylight which is the last thing you want to do at night in my opinion. The old sodium lights might have had unnatural colour rendering (or in the case of low-pressure entirely monochromatic amber) but this was a small price to pay for warm outdoor lighting. There's no reason SOX and SON bulbs can't be approximated more efficiently with LEDs, we could have the economic benefits of LEDs without the horrible side-effects of cheap and nasty ones.

I'm not sure where a previously sensible industry decided ultra-harsh daylight bulbs were warranted literally everywhere, in the past harsh white halide bulbs coexisted with sodium ones for decades and there was always guidance on when to use gentle sodium versus harsh halide lights. Apparently everything needs to be as harsh as possible these days, damn the institutional knowledge. I'm not anti-LED but I'm anti-'lots of blue spectral content at night' regardless of the source.

adrian_b3• 2 days ago

I completely agree.

I am very happy with my indoor LED lamps, but outdoors wherever the sodium-vapor lamps have been replaced I hate their replacements.

While replacing high-pressure sodium lamps with LEDs brings a somewhat better energy efficiency, the low-pressure sodium lamps already had a similar energy efficiency.

theodorethomas• 2 days ago

I wondered if a city-wide synchronised Pulse-Width-Modulation of LED lights could allow astrophotography (or even naked-eye astronomy) to be possible again, with a filter synchronised to the off-cycle.

fhdkweig4• 2 days ago

Los Angeles has the Griffith Observatory. To allow the city to have street lighting while not interfering with the observatory, the lights are sodium vapor lights that emit a specific wavelength that the observatory can filter out. Since LEDs also use specific wavelengths, this could have been done.

I was disappointed that the article didn't mention this, especially because they did mention sodium, but only as a pretty color.

OkayPhysicist• 2 days ago

I quite like the 2 wavelength light that sodium lamps give out. When I was in school, my university gradually went from all sodium to all LED, and it was definitely a loss. The complete loss of hue, combined with the soft buzz of a dying sodium lamp had a certain otherworldly feel to it. I found it quite relaxing.

Rotundo2• 2 days ago

Using PWM to dim lights should be banned wholesale. Many people, me included, get crazy headaches from the worst lights and mild discomfort from the best ones. It's also completely unnecessary as non-flickering bulbs do exist and are readily available for the same price.

weberer• 2 days ago

Those are probably 50-60 hz flickering from the mains frequency rather than PWM. (Or 100-120 hz due to the rectifier). Actual PWM ICs drive LEDs over 10,000 hz, which is truly imperceptible to the human eye.

esikich4• 2 days ago

That's unrectified LEDs flashing at mains frequency, not PWM.

coryrc• 2 days ago

No, because the phosphors glow for much longer than human persistence of vision.

uv-depression5• 2 days ago

Greenhouses here in the lower mainland of British Columbia have been devastating to the night sky. It's quite depressing how little society values the night sky, something that's been an important part of every human culture for longer than recorded history. I've taken friends out to thoroughly mediocre skies (Bortle 4-5) and they've been very impressed, because they're used to city lights (Bortle 9) where you can maybe see a few of the brightest stars and planets.

If you've never seen truly dark skies, do yourself a favour and go see what they look like during true night. Bring binoculars if you have them, maybe get a planisphere and a (dim!) red flashlight.

The lack of respect for the night sky includes starlink and the other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet, by the way. It's been a huge hit to the field of astronomy. Before someone inevitably says "we should just be putting telescopes in orbit", orbital observatories are obviously a huge deal and I support building more of them, but you simply can't put things like the ELT (40m primary mirror, 2800 tonnes) or the Square Kilometre Array in space.

bpodgursky5• 2 days ago

Dude your country is 98% desolate and unsuited to agriculture. If you want night sky go to a cabin literally anywhere in your unending and cold mountains instead of shutting down agriculture in the only marginal spot on the west coast you can grow food.

magicalist• 2 days ago

instead of shutting down agriculture in the only marginal spot on the west coast you can grow food.

Not an expert, but I would think greenhouse light pollution is not necessary for agriculture? It seems like obvious waste (money spent generating light that isn't going to photosynthesis), but I assume it's cheaper not to shield the lights than to shield them, so it's a matter of ROI and requiring people take care of their externalities.

Is there an economic argument that light shields will make agriculture in that area too expensive?

drdexebtjl3• 2 days ago

The entire world’s agriculture “shut down” at night before we decided we want every crop to be available everywhere year-round.

Just install light shields.

uv-depression5• 2 days ago

I can't just casually hop up to the Yukon for an evening of astronomy. It's about a thirty hour drive. Even relatively small towns have exurbs now because of our terrible city planning, so light pollution extends shockingly far. Alberta's probably the worst, almost the entire province (about the same land area as Texas) has light pollution.

instead of shutting down agriculture in the only marginal spot on the west coast you can grow food.

The Okanagan will be shocked to hear they can't do agriculture! Perhaps we could just turn off the greenhouse lights for a couple hours, or install retractable shields/mirorrs on top of the greenhouses.

eliaspro2• 2 days ago

This is not only about being able to see a nice night sky (although I admit I love seeing one), it's a very much more fundamental issue.

Light pollution has dramatic negative consequences for wildlife and thereby our ecosystem we so heavily depend upon.

micromacrofoot3• 2 days ago

or you know, just adjust the lights a little

throwforfeds• 2 days ago

I hadn't been out to a dark sky in years so I went out to a deep part of Joshua Tree (Bortle 2-3) one night not too long ago just to see some stars. Wow, I was not expecting that many Starlinks up there.

kccqzy• 2 days ago

National parks in California are indeed amazing. One time during a group trip to Death Valley, people were so amazed by the night sky that half decided to sleep outside the tents just to experience falling asleep while looking at the stars.

everdrive• 2 days ago

It's quite depressing how little society values the night sky, something that's been an important part of every human culture for longer than recorded history.

But what if someone were uncomfortable briefly? Did you ever consider that? Technology exists to infantilize us while slowly ruining everything that makes us human. Shame on you for attempting to interrupt human progress.

adrianN2• 2 days ago

Putting astronomy on the dark side of the moon would probably work better than putting it into space because you can use some local material for construction.

uv-depression5• 2 days ago

There isn't a single "dark side" of the moon that's always in darkness, the "dark side" of the moon is the side that always faces away from us (poor choice of name). It's fully illuminated during a new moon.

Lunar regolith would probably be quite damaging to optics. It's nasty stuff. I have seen ideas for building liquid mirror telescopes on the moon, though.

shagie2• 2 days ago

The far side of the moon would be useful for a radio observatory where one can block the noisy Earth while taking advantage of the ability to construct large collection area dishes (think Arecibo in a crater - https://en.wikipedia.org/wiki/Lunar_Crater_Radio_Telescope )

As to the dark side of the moon, I would suggest a read of the story "A Walk in the Sun" - https://www.baen.com/Chapters/0671878522/0671878522___1.htm (the dusk terminator moves at about 10 mph (15 kph) at the equator).

PaulHoule2• 2 days ago

In space though you can do extremely lightweight construction because structures don't need to support their weight against gravity unless they are huge enough that tidal forces matter.

Like O'Neill's research group killed off the plan with the big cylinders because you would construct solar power satellites out of plastic films with vapor deposited metal and semiconductors and these would be light enough to send up from Earth and assemble in space.

chasil• 2 days ago

I have read elsewhere that spinning mercury would be used as the mirror.

kortilla• 2 days ago

other internet providers dumping tens of thousands of satellites in orbit instead of building municipal internet

Ah yes, that municipal internet in the Pacific Ocean. The municipal internet in the 1 person per square mile rural area. The municipal internet to mountain villages. The municipal internet running to airplanes. The municipal internet to the Antarctic research stations.

Tell me you don’t know the point of satellite internet without telling me.

If you want to make arguments against sat constellations so people can make long exposure photos, go for it. But don’t pretend there are actual viable alternatives to LEO sat internet.

wussboy• 2 days ago

Maybe it's okay for there to be places on the earth where high sped internet is not available?

drdexebtjl3• 2 days ago

The municipal internet in the 1 person per square mile rural area.

Yet that person can receive mail, is within a few miles of a major highway, and is likely connected to or close to the electric grid.

Infrastructure is expensive. LEO Satellite internet is only cheaper because the environmental cost is not being accounted for.

micromacrofoot3• 2 days ago

Humans have been looking at the stars every night for tens of thousands of years and we've essentially occluded the night sky to most in the matter of about 50 years, I don't even think most people know what we've lost anymore.

Hilliard_Ohiooo• 2 days ago

It's not that big a deal for MOST people. I was on navy ships transiting the Pacific it's as dark as it can get on deck and sure, it's magical and spectacular (especially the NUMBER OF SHOOTING STARS!) but even in the middle of the ocean 99% of my fellow sailors could not have given less of a shit. I'd sit out there for hours and they all though I was a weirdo for it. So, while amazing, most people don't understand or care to understand the enormity of what's going on around them.

Most people didn't care about dark skys in the first place and still don't.

bilekas• 2 days ago

Had s similar experience in the saharah desert.. I love all things space and have a teleclscooe I use regularly but seeing it in person and just laying down and watching for hours was another experience.

I would argue that probably not looking up all the time at night with predators around was an evolutionary trait though! (Semi joking)

chickensong• 2 days ago

There are a lot of Muggles in the world.

dfxm12• 2 days ago

Depends how far back we go for "first place". Stars are an interesting intersection of social sciences, hard sciences, and even some woo for a very long time. We must consider their interaction between religion, astronomy and astrology going as far back at least as history lets us.

retired• 2 days ago

In parts of The Netherlands is simple never gets dark due to light pollution. It feels like it is always dawn. Pretty bad for your sleep cycle.

Some pictures: https://milieufederatie.nl/nieuws/6-op-de-10-nederlanders-wi...

pdpi3• 2 days ago

Most people didn't care about dark skys in the first place and still don't.

Most people were never given the opportunity to care.

doix• 2 days ago

Today I learned about the Bortle scale. I was completely ignorant about it.

If you've never seen truly dark skies, do yourself a favour and go see what they look like during true night

I think I went from only ever experiencing Bortle 5-6 to Bortle 1 when I visited Merzouga and Erg Chebbi. Blew my mind, made me really appreciate the extent of light pollution almost everywhere else I've been.

pdpi3• 2 days ago

Today I learned about the Bortle scale

When I first learned about the "clouds are noticeably brighter than the sky" part of Bortle 5, it was like it flipped a switch in my brain. I can't avoid noticing it now.

wompawoo• 2 days ago

Check out southwestern Ontario as well. I've driven through there on my way to Michigan a couple times. It's purple at night. The sky is purple.

SoftTalker• 2 days ago

I would have assumed that most plants need a daily light/dark cycle but maybe not?

NoMoreNicksLeft• 2 days ago

The world record holder vegetables are all grown in Alaskan summers, up north... where they get 20+ hours of daylight per day. Dunno, maybe the CAM plants would do bad (pineapples) but just about everything else benefits.

tredre33• 2 days ago

Most fruit crops need 8-12 hours of darkness but it changes depending on which point they're at in their life cycle. 20 hours of light is usually fine during the initial stages, then they require 8-10 hours of darkness to bloom, then back to 18-20 hours of light during the fruit growth.

(I'm not a botanist or a farmer but I grow greenhouse veggies for fun)

qurren3• 2 days ago

Starlink gets a lot of flax for it but as an avid night sky photographer myself (IG: @dheeranet) who regularly goes to Bortle 1 parts of the world, I haven't found them to be an issue at all.

1. They are only visible when they are spinning up to orbit

2. They are too dim to desensitize your eyes, and are extremely easy to remove with the most basic of outlier rejection techniques; netizens often amplifiy outliers by max-stacking instead of outlier-rejected mean-stacking to make Starlink look much worse than it is

3. Lights from planes have ALWAYS been much, much, much, much worse than satellites. They still aren't particularly a problem for imaging if you know how to outlier reject, and their paths are known, predictable and trackable

I'm not an Elon-fan or anything but just giving a dose of objective reality here.

Not to detract from TFA's real issue which is light pollution from cities -- that's an actual issue as the regions of dark sky are shrinking.

uv-depression5• 2 days ago

(1) Considering there are now multiple companies planning to launch their own fleets of tens of thousands, satellites need replacing, etc, even if this was completely accurate, this will be a continuous and ongoing issue as it has been for years.

(2) The standards for astrophotography and for professional astronomical measurements are somewhat different! Also, I think you meant median stacking; mean stacking doesn't handle outliers as well.

(3) Whataboutism. Besides, you'd get no argument from me about replacing the majority of air travel with high speed rail, even without considering lights.

I agree that city light pollution is probably the bigger problem, especially for the amateur/cultural angle, but these are two symptoms of the general cause of our economic system not valuing the sky (or the environment generally).

garbagewoman• 2 days ago

Both are real issues, to be clear. LEO satellites are a real and increasing issue.

Reason0772• 2 days ago

As a “night sky enthusiast”, as opposed to a real astronomer, Starlink and other satellites do not bother me much.

There’s certainly more of them than there used to be, but the satellites aren’t bright enough to affect your eyes or distract too much from the stars. If you do see one it’s a fun little exercise to try and figure out what it is!

Ground-based light sources are the real threat to night skies.

culi4• 2 days ago

Starlink has over 10k currently but has applied for at least 42k. And because it's now a US military technology, every other country is building its own. China is planning on launching over 12k satellites and Russia is working on their own.

It's too much

NooneAtAll3• 2 days ago

They are only visible when they are spinning up to orbit
and are extremely easy to remove with the most basic of outlier rejection techniques; netizens often amplifiy outliers by max-stacking instead of outlier-rejected mean-stacking to make Starlink look much worse than it is

my understanding was that they are a problem on much bigger scale than yours "one dude with mobile telescope (or maybe just a camera?)"

sure, we don't have many film observatories anymore (where max-stacking is literally only thing they can do), but a lot of lower-to-medium scale observatories get polluted observations with not enough funding to clean up easily or too small FoV for cleanup to matter - frame gets ruined, observation needs to be longer for effect

matkoniecz• 2 days ago

instead of building municipal internet

Starlink is intended and used as solution for places and uses for which municipal internet is not an option at all

(is it usable at all as replacement for municipal internet? I would guess that you would overcrowd connection quite quickly)

Reason0772• 2 days ago

Wanaka, in the South Island of New Zealand, still has pretty good views of the night sky. You can see an awful lot more stars than you can from major cities.

But even here it’s under threat: a recent new retail development on the edge of the town (called “Three Parks”) emits so much light that it illuminates the nearby hills at night. The sad thing is that much of this light seems unnecessary to me: eg a hardware / garden retailer has enormous floodlights to illuminate their inner courtyard constantly at night, even when they’re closed.

The rest of the town has always been pretty good at minimising light pollution, with soft, modest and well designed street lighting in residential areas. But such considerations have been forgotten completely with the new development. Three Parks emits more light pollution than the rest of the town combined!

anal_reactor• 2 days ago

Are there places in EU that are dark and easy to visit?

yodsanklai2• 2 days ago

In the EU, the canary islands are known to have great skies. You check this map https://www.lightpollutionmap.info

I've been in some place with very dark skies, like Death Valley or Teide in the Canaries (https://www.teidebynight.com/tenerifes-dark-sky-reserves-hav...). It was great, but also not that much better than what I've seen closer to home in French countryside or in the alps. Maybe I didn't get the best conditions though.

yodsanklai2• 2 days ago

It's quite depressing how little society values the night sky,

Considering how little value we put on far more important things (like the climate or biodiversity), I'm not really surprised.

hectdev• 2 days ago

I've started doing this in my home. All lights are smart LEDs. At 8pm, they shift warm, 80%. From 9pm-10pm, they go from 80% to 0%. At 7am, they start going from 0% to 100% cool (I work from home and it helps with focus).

Having my environment reflect the patterns of nature has really been a nice change.

Marsymars2• 2 days ago

I do something similar with my exterior lights - at sunset my lights come on at ~1% at 2000K. If they detect motion (in my driveway or back deck) they go up to 100% at 2700K. At sunrise they turn off.

Note that bulbs exist that automatically warm as they dim - so in my case the switches are smart, but the bulbs themselves are all dumb.

redmaple8923• 2 days ago

What type of system are you using outdoors?

binarymax• 2 days ago

Our city recently went on a crusade on replacing all of the high pressure sodium bulbs with LEDs, with the justifications of driving safety and energy savings. I agree that these are important, but the LED bulbs they chose are actively hostile to homes and pedestrians. They are blinding. You can't look at them. I have one outside our house in the main viewing angle and we need to close our shades as soon as they are turned on.

pelotron• 2 days ago

Back in the day the city installed a new streetlight that blinded anyone sitting on the front porch of my grandparents' house, which they liked to do in the evening. So Granddad got out a painter's pole and rolled some white paint onto the side that faced his house. Problem solved and no one ever said anything.

culi4• 2 days ago

:rock: + :slingshot:

kakacik• 2 days ago

-> repair, if repeated police or company will maybe put on a little camera, and then suddenly your hobby lands you in jail with enough time in to ponder why childish behavior is ruining one adult's life

jacooper• 2 days ago

I would 100% rather have a truly bright and lively city at night than a visible night sky. More than half the year is in the winter ffs!

throwatdem12311• 2 days ago

All the car headlights for new cars in Canada are LED and it makes driving at night painful and dangerous. So many times I’ve been nearby blinded by them and I can’t see anything ahead. And it actually physically causes me pain.

yonatan8070• 2 days ago

But is that the fault of the LED? That sounds like the fault of whoever calibrated the LEDs' brightness and directionality.

If the beams were the right brightness and pointed downwards, we wouldn't be having this issue.

GrinningFool• 2 days ago

Not really. When incandescent headlights are mis-aimed, it is generally not nearly as blinding or painful [for standard car headlights]. Mis-aims happen - it shouldn't be a risk to other drivers when they do.

throwaway173738• 2 days ago

There will always be situations where you’ll be under the cut point of a low beam. If there’s a small incline then a flat intersection the drivers opposite the incline get the fill low beam. It’s part of what makes HID lighting dangerous to pedestrians. It obscures the vision of oncoming drivers turning left or right. Also if an automatic headlight system doesn’t react to turn the high beams off it will blind people.

bahmboo• 2 days ago

I'm optimistic this won't be a problem in 10-20 years (I agree that's a long time). We have the technology in matrix headlights that were banned in the US and basically in Canada up until a few years ago. I expect to see kits on Amazon in a few years for retrofits. Since they need a camera and some brains they will likely start at many hundreds of dollars but that should come down.

redmaple8923• 2 days ago

I read the entire article and am really glad the author took time to write this down and for OP for posting. I am so tired of poor (mostly outdoor) but also indoor lighting. I have felt crazy feeling that the so-called "better" LED's in parks and on paths have felt like less lighting. Unfortunately I think changing things (in the US) often requires proving harm...science and aesthetics don't seem to matter much at all many place.

chrisweekly2• 2 days ago

For those in the northeastern US, I highly recommend a visit to Mesawisla in Maine, it's a national dark sky park with cabins and an AMC lodge that provides fantastic food.

chrisweekly2• 2 days ago

argh, typo, too late to edit

Medawisla

https://www.outdoors.org/destinations/maine/medawisla-lodge/

miladyincontrol• 2 days ago

I think people focus far too much on the temperature of LED street lights and rarely on the CRI. The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI.

Dare I argue even I would choose 6500k LED street lights with decent CRI over poor CRI 2700K LED lamps any day.

tredre33• 2 days ago

The night will still feel odd and "soulless" even with 2700k LED street lamps so long as they're still the absolute worst CRI.

What makes you say that the CRI causes the lack of soul? I'm not saying that you're wrong, but given that CRI is objectively better than it ever was now, why?

The sodium lamps we used previously had a CRI of 25-35. The absolute worst white LEDs we have have a CRI of at least 60.

krackers• 2 days ago

Sodium vapor lamps didn't exactly have high CRI either

apparent2• 2 days ago

The use of solid-state technology gives the lights an extraordinary life-span, often measured in decades rather than years.

I have found this not to be the case. They seem to last several years, but not an amazing period of time. Also, the ones that were installed in my home are quite expensive, something like $45 per can (the whole thing must be replaced), and the price to install is $30 per can because the company changed their plug design in the last 5 years. So I end up spending $75 for each light, which is roughly $10 per year per light (per light-year?). That doesn't strike me as a great value, especially because I can't change the lights myself due to the wiring/plug situation. Maybe that piece won't apply in future years, but it's still a lot even if it's just $45 for the darn can.

aidenn0• 2 days ago

Yes, I was wondering if they really last longer than sodium-vapor lamps, which last about 5 years at a 50% duty cycle.

apparent2• 2 days ago

I imagine they last longer than some other types, but it hasn't been an order-of-magnitude difference that was advertised. Also the cost/hassle is much more than expected.

We've put some smart LED bulbs into some fixtures, and those have been fine. But they've only been in for a few years, so we don't yet know their lifespan.

adrian_b3• 2 days ago

I have seen a lot of complaints about LED lamps with a short life, usually caused by defects in their integrated power supplies, typically arising from bad cooling.

On the other hand, I have more than a dozen LED lamps that have been continuously used for more than ten years and none of them has failed yet. They are mounted in classic Edison fixtures for incandescent lamps and they were made by Philips, but at the time when they were bought they were one of their better models, and having a 4000 K color temperature, i.e. very slightly yellowish, but not noticeably yellow, like the lamps with a color temperature less than 3000 K, which try to imitate incandescent lamps.

ssl-3• 2 days ago

At home, my solution to that is to use lighting fixtures have Edison sockets inside for a bulb to screw into, just like they always used to.

The fixtures last forever, and may have already been there for half a century. It doesn't need changed.

The bulb lasts as long as it lasts, but is easily replaced. It can be dumb, or it can be smart. It can be changed for different color temperature or CRI or protocol or efficiency rating or whatever.

Sparkyte• 2 days ago

The lights are not just impacting space but ecosystems switching to LEDs can save ecosystems too.

ButlerianJihad• 2 days ago

Since I picked up a Pixel phone, I've been doing some amateur astrophotgraphy, and mostly from the balcony at my apartment.

However, I live in a built-up urban area, and my home is absurdly light-polluted. Like, you wouldn't believe it! The parking lot here is ringed with flood lamps that are aimed into our windows. So every hundred feet or so, there is a bright-as-the-Sun lamp in my face, and with a clear view, I can spot about five of them.

So from my balcony, my only hope to get some darkness for the camera is to get into shadows. The railings provide a band of shadows that I can use to block the floods from getting on my lens. So if I position the camera juuust right, it kinda feels darker than it is, and I've got to say I've captured some impressive starfields, down to magnitude 9 or dimmer, including bodies such as Uranus and 4 Vesta.

I also found that the ballcourts in the rear of my property provide this unique "cave" situation with lots of shadows where I can capture the sky directly overhead, and to the west. This is how I photographed the last lunar eclipse.

Now that's my view to the west and 225° (due southwest). If I go on the other side of the property to look east, I've got the same crazy situation with flood lamps, but there's basically no way to hide in shadows. I literally cannot photograph anything rising in the east if it is dimmer than the Moon.

So really, my astronomy hobby mostly consists of doing some great editing, curation, identification, and mostly simulation from the comfort of the air-conditioned indoors. I enjoy what sightings I can while outdoors, and that's included some meteors, the ISS, Tiangong, and a few Vandenberg launches. We're still hanging in there!

worik• 2 days ago

We have been working hard on this in New Zealand, in the South Island

We started in Tekapo (https://www.darkskyproject.co.nz/) which being rural with a very low population density, and mountainous and with existing observatories to protect

In recent years the effort has moved into the cities (https://www.dunedin.govt.nz/council/policies,-plans-and-stra...)

Interestingly people who live on hills, overlooking the suburbs, complain the lovely view of the sparkling streets was going dark!

But not only does it preserve the stars it is much cheaper, so not going back

Point is: this can be done and the nighttime rewards and financial rewards make it worthwhile

wkjagt• 2 days ago

I am Dutch but live in Canada, and when I visit family in The Netherlands, I always notice how much darker it gets during the night, even when my family lives in a larger town than me.

groos• 2 days ago

I read through most of the article but didn't see motion sensors mentioned. A lot of suburban streetlights are lighting up empty streets at night. With a combination of motion sensing and LEDs, lighting could follow pedestrians. Cars really don't need street lights in most cases but even then, in higher risk areas, motion sensors could turn on streetlights just as long as needed.

wffurr• 2 days ago

A motion sensor activated light unpredictably turning off and on on my street would be worse than the steady street lamps we have now. It would be even more distracting and annoying.

thayne4• 2 days ago

I'm surprised it didn't suggest using red LEDs without phosphorescence, which has several advantages:

1. Red light preserves your dark adaptation

2. It doesn't have as much of an impact on your circadian rythm

3. Not using phosphorescence can increase the lifetime of the light, since you don't have to worry about the coating degrading

4. Red light is less energetic, so could potentially use less power.

5. Since an LED without phosphorescence is a single wavelength, telescopes (and binoculars) can use a narrow band filter to filter out the light pollution, without blocking most of the light from celestial objects.

dwoosley• 2 days ago

“… gives the illusion, without the reality, of safety”

This actually isn’t true. Having done physical security work before, a weird fact is that one of the best physical deterrents is lighting; even over CCTV.

I don’t say that to take away from this, this is great work and I’d love to see the lighting toned down for multiple reasons. However, this should be framed as a security tradeoff not an outright win.

Source: The Impact and Policy Relevance of Street Lighting for Crime Prevention: A Systematic Review Based on a Half-Century of Evaluation Research (https://www.crimrxiv.com/pub/wl9zqxga/release/1)

LanceH• 2 days ago

Driving down the road past a police cruiser on the side with it's lights on is far from safe. The escalation of brightness makes them visible beyond anything else...like the road.

mchusma• 2 days ago

I am generally for a light government touch, but I think excessive light and sound are forms of pollution and should be generally regulated in a not-overly burdensome way (give people fix it tickets etc). Policing excessive light, and excessive blue light, would be pretty trivial. And I think cameras that automatically ticket loud vehicles would be amazing.

peter_stokes• 1 day ago

sodium lamps are much more iconic and pretty. LEDs are gross and soulless

LEDs’ potential to save our night skies

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