Comment by uv-depression
1 day 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.
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.
> 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
I don't see how this can be true especially if you have a fancy telescope tracking something, take 3-5 whatever many shots in succession and stack. It's astrophotography 101.
6 replies →
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
Deep dusk will be quite a disco ball.
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.
Both are real issues, to be clear. LEO satellites are a real and increasing issue.
Yes, but one is a vastly smaller issue than the status quo issues.
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 replies →
(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).
Some good points. However:
> 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.
11 replies →
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.
> 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.
Very true, but isn't that exactly what the parent is suggesting? That even a ship full of sailors given the opportunity to care, very few do?
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?
1 reply →
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)
There are a lot of Muggles in the world.
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...
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.
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.
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.
> 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.
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.
[flagged]
1 reply →
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!
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.
> 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.
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.
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.
Of course the dark side of the moon is illuminated by the sun at times. But it has minimal human illumination, so that's pretty nice.
1 reply →
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).
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.
I have read elsewhere that spinning mercury would be used as the mirror.
The suggestions that I've seen for astronomy on the far side of the Moon have largely been about radio astronomy rather than optical. The lack of the ionosphere which otherwise blocks and distorts 10 meter and longer radio and using the Moon itself as a shield from the radio noise of Earth makes it more interesting.
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...
---
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.
> 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.
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.
I would have assumed that most plants need a daily light/dark cycle but maybe not?
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)
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.
> 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)
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.
Are there places in EU that are dark and easy to visit?
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.
> 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.
Maybe it's okay for there to be places on the earth where high sped internet is not available?
> 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.
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.
> 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?
I mean it's not easy to have greenhouse walls that let sunlight in but don't let grow light out. You can direct the light but you are going to have loss.
2 replies →
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.
Yes it has negative consequences for wildlife, which is why it is FAR BETTER FOR THE ENVIRONMENT to put all the agriculture in one place at high efficiency rather than spread farmland out over otherwise virgin wilderness.
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!
2 replies →
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.
What are you on about? Literally drive north a bit towards Whistler, you can get out of the light pollution in an hour or two
lightpollutionmap.info/#zoom=8.01&lat=49.6027&lon=-122.7672&state=eyJiYXNlbWFwIjoiTGF5ZXJCaW5nUm9hZCIsIm92ZXJsYXkiOiJzYl8yMDI1Iiwib3ZlcmxheWNvbG9yIjpmYWxzZSwib3ZlcmxheW9wYWNpdHkiOiI2MCIsImZlYXR1cmVzb3BhY2l0eSI6Ijg1In0=
1 reply →
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.
Yes we also had a population of 50 million and 10% of them starved to death every time a volcano burped, they were great times.
2 replies →
or you know, just adjust the lights a little
[flagged]
>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.