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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.
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.
> 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
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.
It's too much
Starlink gets a lot of attention because it's new, and because it's run by a polarizing guy who sucks.
Meanwhile, the airplane and streetlight situation has been destroying night sky photography for decades, to the point where photographers consult charts and have communities tracking the best times of years to minimize the hours of driving you have to do.
But let's "both are real issues" it, sure.
(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).
> replacing the majority of air travel with high speed rail
I absolutely LOVE high speed rail, but I will note that it is correlated with far more light pollution than air traffic. I say correlated because typically high speed rail is routed through high-density population centers, but if there aren't population centers, you'll have to have plans to create them in order to support the rail system itself.
Basically there is nowhere in the world that has both high speed rail AND suitable for astronomy. If you want to find dark skies in China for example you have to get far away from all the high speed rail areas of the country.
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.
Or are you suggesting that by the time they are in the Navy, it's after the age where one might be most easily encouraged to care?
I would argue that probably not looking up all the time at night with predators around was an evolutionary trait though! (Semi joking)
Some pictures: https://milieufederatie.nl/nieuws/6-op-de-10-nederlanders-wi...
Where I live, it usually impossible due to nights being too cold (okay, you can use sleeping bags/extra blankets etc), clouds, or... mosquitos.
But when/where it's not: highly recommended! "Spaceship Earth" in progress.
> 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.
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.
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!
Considering how little value we put on far more important things (like the climate or biodiversity), I'm not really surprised.
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.
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).
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.
Radio telescopes only need a wire mesh to deploy (rather than polished optical mirrors). https://www.skyatnightmagazine.com/space-science/arecibo-tel... has a view under Arecibo.
https://www.nasa.gov/general/lunar-crater-radio-telescope-lc...
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The liquid metal mirror telescopes https://en.wikipedia.org/wiki/Liquid-mirror_telescope are interesting in part because you can get liquid mercury temperatures near room temperature on Earth.
It's theoretically possible for the moon - https://ui.adsabs.harvard.edu/abs/2007Natur.447..979B/abstra...
... But this seems a bit more speculative. It wouldn't be mercury and requires a yet to be discovered liquid metal that is stable for months at 175 °K.(I'm not a botanist or a farmer but I grow greenhouse veggies for fun)
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)
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.
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.
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.
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?
Light pollution has dramatic negative consequences for wildlife and thereby our ecosystem we so heavily depend upon.
Would you rather have 2x the wilderness 80% degraded or 1x the wilderness 90% degraded? Unless your plan is to decide who starves to death, it's far better to have greenhouses where we already have farms!
> 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.
lightpollutionmap.info/#zoom=8.01&lat=49.6027&lon=-122.7672&state=eyJiYXNlbWFwIjoiTGF5ZXJCaW5nUm9hZCIsIm92ZXJsYXkiOiJzYl8yMDI1Iiwib3ZlcmxheWNvbG9yIjpmYWxzZSwib3ZlcmxheW9wYWNpdHkiOiI2MCIsImZlYXR1cmVzb3BhY2l0eSI6Ijg1In0=
Just install light shields.
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.
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)
(I find it odd; dark-adapted eyes see a lot, including movement in shadows or low-contrast obstacles - after all, our bodies know how to see well at moonlight levels of illumination. Why are we so keen to kill this ability?)
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.
Powerful lights are known to actually increase safety risks. Our nightvision is reduced and the shadows of the lights are the most dangerous parts. Perhaps more dangerous than no light at all.
Once city (I can't recall which) had a really cool solution to this where they installed string lights. Lots of small, dim lights don't negatively impact your nightvision, keep the path pretty visible, and don't cause too much light pollution
This is a completely irrational (though commonplace) fear. Criminals aren’t hiding out in bushes in desolate parks to mug or rape random people. Muggings most commonly happen in side paths off of busy high streets because criminals, being people, like to hang out in stimulating places where they won’t get bored. They’re not going to be donning ghillie suits and lying patiently in wait for however long in uncomfortable brush for a hapless victim to cross their path. The muggings are crimes of opportunity. Rapists are most commonly somewhat trusted friends or acquaintances who have access to people when they’re in vulnerable states in private, protected spots.
Thinking parks and parking lots need to be lit up like Christmas to deter crime is just a veneer of rationalization to cope with the standard childhood fear of the dark. It is not backed by data or evidence. The actual main public safety concerns when it’s dark out are trip-and-fall hazards or collisions with or vehicles who can’t react fast enough when things pop out at them, not muggers and rapists. Having the nighttime environment overly lit actually makes shadows starker and blows out people’s night-vision so they can’t find things. If anything, it makes the edge case where Sam Fischer is hiding in the bushes more dangerous rather than less.
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
Amber LEDs could provide a similar experience.
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.
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.
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.
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.
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.
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...
Dare I argue even I would choose 6500k LED street lights with decent CRI over poor CRI 2700K LED lamps any day.
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.
Having my environment reflect the patterns of nature has really been a nice change.
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.
* Smart switches: Lutron Caseta. (With the dimmer for ELV lighting so I can use the middle button for specific brightness/warmth levels.)
* Outdoor bulbs: Philips warm glow bulbs. (2200K-2700K warm dimming, 95 CRI - these ramp from 0% at 2200K to 100% at 2700K)
* Outdoor recessed lights: Globe Electric DuoBright LEDs (2000K-5000K warm dimming, 96 CRI - these ramp from 0% at 2000K to full lumens at 3000K at 80% the dimmer, but then will continue to ramp from 3000K to 5000K at full lumens if the dimmer is turned up.)
* Motion sensors: Philips Hue Outdoor sensors.
Non-smart bulb availability is kinda weird, my specific bulbs may be discontinued or unavailable outside of Canada, but I'd expect local alternatives to be available.
If the beams were the right brightness and pointed downwards, we wouldn't be having this issue.
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.
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.
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.
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.
Medawisla
https://www.outdoors.org/destinations/maine/medawisla-lodge/
And it's usually recognized that 1,000hz is the bare minimum to spare sensitive individuals from symptoms, with 2,500 usually used for safety margin. Then you have to account for some jitter in the synchronized network so you're looking at at best a 1/5,000 exposure.
Is that sufficient to be worth the trouble?
But then you can get capacitors or inductors emitting a very annoying 10 kHz whine. There are higher end LEDs for various commercial uses that use PWM at over 20 kHz to avoid that.
I was disappointed that the article didn't mention this, especially because they did mention sodium, but only as a pretty color.
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
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!
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.
(Everything is relative. I expect more from IEEE than the NYP or the Daily Mail, as extreme examples.)
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.
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.
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
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.
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.