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Really cool thanks for the link. I have experimented a lot with the OOK modulation and open-air laser wireless communication. It can be done just using visible light LEDs as detectors and small laser diodes, they just need to be of the same color. A free-space optical link can be built in minutes, see https://github.com/gioblu/PJON/tree/master/src/strategies/An...
>lasercom

I'm calling it tight-beam and you can't stop me

Banks reference?
Not OP, but it is used in the expanse: https://old.reddit.com/r/TheExpanse/comments/2v9ej6/tightbea...
It is used in Expanse but as about any such nomenclature (belter, spaced, burn, etc.) it's using existing tried and tested SF nomenclature as it should instead of creating new one.
Free Space Optical Communication(FSOC) enables projects like Taara[0] from the Alphabet's X. This communication enables great internet infrastructure around Africa, especially coupled with already existing Telecommunication companies Fiber Optics(Project Equiano). [0] https://x.company/projects/taara/
I'm not sure what's new here. TV companies and others have been beaming data through the air with lasers for at least 30 years.

When I worked in the television industry, it was how some of the TV stations in New York world get their skyline video back from their towercams in New Jersey. This was late 1990's.

It was my understanding at the time that it didn't work well in rain and fog, but that was O.K., because there was nothing to see then, anyway.

I can't wait until Starlink starts implementing their planned optical links and unleashes intercontinental lower-than-fiber latency.
The capacity of these systems seems really tiny by modern standards as well as highly power inefficient. The fastest link demonstrated was around 5Gb/s at ~160W. This is about 3 orders of magnitude worse from an energy per bit perspective than fiber based systems. From that point alone, it’s hard to imagine these systems being cost competitive with existing fiber infrastructure. From a system capacity perspective these systems are about 500x less capacity.

On page 26, it seems the primary application is being able to get more data down to Earth for remote sensing applications.

The most important application of lasercom from LEO is direct-to-ground downlinks since the main point is being able to download to Earth the increasing amount of data that remote-sensing missions require

Well, yeah, "space communication" in the title really means "SPACE"-- as in not on Earth.

There's interesting considerations in space laser communications that you don't see in fiber such as "point-ahead" optics to account for the fact that the speed of light is finite and the target is moving. This can be thought of as the optical equivalent of peeing into a moving bucket.

It's a fascinating review article.

They may "unleash intercontinental lower-than-fiber latency", but they also unleash light pollution.

Where do you live? In most of Europe and SE Asia you can get gigabit broadband.

I think SpaceX is a cool company and I could see myself work there, but StarLink is, IMHO, a shitty project that ruins the night sky and space for everyone. https://en.wikipedia.org/wiki/Starlink#Criticism

Would you feel the same way if observatories were lifted beyond Earth orbit where their view was never obstructed? There is so. much. space out there, and it seems silly to argue over the artificial scarcity of clear sky when we can solve this with technology. We’re even putting a global comms network in place that could support high speed science data store and forward from space observatories to science consumers on ground.

What if we could churn out orbital science platforms as fast as SpaceX churns out Starship SNs and StarLink satellites?

If you look at the article I linked, you can clearly see that the satellites are visible from the ground (the photo from Germany). If you search for "starlink" on Flickr you can see more examples.

This is light pollution.

The reason you're getting downvoted is that your base argument is that we shouldn't have cars because then there won't be picturesque horse pastures to look at. The same has been said about offshore wind.

Increasing global networking, and doing so in a ground-infrastructure-agnostic way, has the potential of connecting billions of people to the global internet in a cost-effective way.

Sometimes, progress outweighs the cost.

And parent comment presented a nice alternative approach for the specific astronomy case.

That’s because they want photos of them. You don’t see them on images where they were removed by stacking.

Try searching for ISS :wink::wink:

>you can clearly see that the satellites are visible from the ground (the photo from Germany)

No, you've misunderstood (in numerous ways, but this is a specific one you've cited). That photo you linked is of a satellite "train", which is a temporary state of satellites after deployment as they take themselves the rest of the way to final deployment orbits. At that point they'll be both spread out and the albedo will be vastly lowered because SpaceX has already made design alterations to the sats so that in their operational alignment towards Earth they are far less reflective. They're not going to interfere with the sky from the naked eye, nor even for general photography, even from low light pollution rural areas vs typical urban ones.

It doesn't help that you're almost a parody of "entitled, dismissive urbanite". Even in the developed world, tens to hundreds of millions of people have crappy DSL at best. Outside of the developed world that rises to billions. Marine and aircraft stand to make enormous gains as well. The demand for Starlink is clear and well founded, and you do your argument zero favors by trying to hand wave it away (unless you just mean to rant to no constructive end).

> you're almost a parody of "entitled, dismissive urbanite".

> you do your argument zero favors by trying to hand wave it away (unless you just mean to rant to no constructive end)

Personal attacks and name-calling are not ok here, regardless of how right you are or feel you are. Please omit such swipes when posting to HN.

https://news.ycombinator.com/newsguidelines.html

I genuinely did not consider those to be personal attacks or name calling, but constructive criticism of the argument given. Dismissing development of universal rural focused broadband because in "most of Europe and SE Asia you can get gigabit broadband" is an implied dismissal of the worth of everyone outside of those privileged locations. It is indicative of a real bubbled perspective, and that's not helpful in convincing other people. And it does indeed to the argument zero favors to ignore it, because compromise is absolutely possible! This doesn't need to be total zero-sum scenario. As well as continued albedo reductions, it's possible to imagine other measures like a tiny tax on large constellation satellite internet specifically for astronomers to help fund space telescopes or other measures. Turning it purely into "this versus that" is a bad idea when "that" will overwhelmingly win. I think most people could understand a reasonable charge to help mitigate an externality.

Nevertheless I accept judgement of you and community here and will try to more carefully consider replies down the road.

Hacker News continue to disappoint lately. I naively thought that by using my real name people here would actually treat me like a real human, not some anonymous punch bag. I don't know who you are "xoa", but that was a very rude comment.

I have provided a Criticism section of a Wikipedia article that points out light pollution criticism from many authoritative sources, including photographic evidence. You dismiss this photographic evidence, but why should I listen to you when I can listen to the IAU, for example? Or Nature? Or the astronomical community?

Quote International Astronomical Union: "The scientific concerns are twofold. Firstly, the surfaces of these satellites are often made of highly reflective metal, and reflections from the Sun in the hours after sunset and before sunrise make them appear as slow-moving dots in the night sky."

Here's an entire article in Nature Astronomy about the issue https://www.nature.com/articles/s41550-020-01238-3

Here's a quote from a Senior Advisor to the European Space Agency https://twitter.com/markmccaughrean/status/11323943469454213...

Here's an entire discussion at the American Astronomical Society about the issue https://aas.org/posts/advocacy/2020/12/impacts-large-satelli...

Here's an article about how the problem will get workse https://www.scientificamerican.com/article/spacexs-dark-sate...

But sure, you call me an "entitled and dismissive urbanite".

I also see the deployment of those massive fleets of satellites in LEO to be suicidal. It makes access to space more complex and expensive. If for some reason few collide they could start a chain reaction that could destroy most LEO satellites now operational and preclude access to space https://en.wikipedia.org/wiki/Kessler_syndrome

>Aggressive space activities without adequate safeguards could significantly shorten the time between collisions and produce an intolerable hazard to future spacecraft. Some of the most environmentally dangerous activities in space include large constellations such as those initially proposed by the Strategic Defense Initiative in the mid-1980s, large structures such as those considered in the late-1970s for building solar power stations in Earth orbit, and anti-satellite warfare using systems tested by the USSR, the US, and China over the past 30 years. Such aggressive activities could set up a situation where a single satellite failure could lead to cascading failures of many satellites in a period much shorter than years.

I am absolutely treating you like a "real human being" and in turn have the respect for you to point out that you are wrong and expect you to be able to handle that maturely.

>including photographic evidence

Yes, which I specifically addressed, and which you have in turn completely ignored. I've followed this as well, and through much more authoritative sources, but in this case your own example was the direct cite. You said "the photo from Germany" which must refer to the one there captioned "Starlink in Tübingen, Germany". But that photo clearly depicts a deployment train, not Starlink satellites fully deployed. Because they don't line up in a train like that in final operational status. That trains might be visible in photographs for a few weeks out of a 5 year lifetime is a very different argument. The caption also does not state what generation they were.

>the surfaces of these satellites are often made of highly reflective metal

Which is generic hogwash. We're not talking about "surfaces often made of" we're talking about Starlink, specifically. Which, as again your own link states:

>"More recent satellites have visors to block sunlight from reflecting from parts of the satellite to reduce its albedo further."

Operational satellites won't be in a train, will be oriented in ways that reduce reflections, and they're actively working on measures to further mitigate albedo. And a core aspect of Starlink is that they have a rapid lifecycle. The impact will probably not be zero, but that must be weighed against the benefits. And the benefits are huge.

>But sure, you call me an "entitled and dismissive urbanite".

I will indeed, because that is how you are acting. Your "Where do you live? In most of Europe and SE Asia you can get gigabit broadband" is flat out INSULTING. I (nor SpaceX for that matter) do not in fact live in Europe or SE Asia (and of course you're implying those outside "most of" are unimportant even there but whatever). I live in America near the Canadian border. I've been fortunate to have 5/1 ADSL from 2000 up until a few years ago with an ISP who were at least local and nice and only charged $45/month for it. Just 40 miles away I know people paying $270/month for 10 megabit service. Others have dial-up or horrible GEO sat internet options or nothing. Many friends in Canada are in the same boat, and that's in the developed part! Take a look at the official Canadian Government National Broadband Internet Service Availability Map:

https://www.ic.gc.ca/app/sitt/bbmap/hm.html?lang=eng

Take some time to go through a few of the layers if you like, but maybe for an initial gut check go to "Aggregated Presentation" and take a look just at "5/1" coverage. And then look at all the empty spots. You can live within 20 miles of the national capital and not even be able to be certain of 5/1 internet. America is in a similar boat, though without as reliable data because the FCC coverage maps are ludicrously generous to industry right now (if even a single household in an entire census block has broadband, the census block is "covered" yet even then massive numbers aren't).

Frankly, even if it really did come down to your subjective feelings about "the night sky" versus decent broadband options for the entire planet? Well you lose. I personally don't think it will be that bad long term, because nobody wants it to be zero sum. There will be continued improvements in lowering albedo, and Starship's massive reduction in space access costs will allow vast new space-based telescope efforts. Heck, we might even ultimately actually get fiber and/or decent WISPs all over the planet, and thus be able to reduce constellations to just what is needed for marine/air.

But the biggest "light pollution" sources for most of the public are ground lights, and astronomers are going to have to accept some compromises for a while because universal broadband is really genuinely important.

Agreed, and LEO trend is just getting started, followed by more constellations by other companies. Light pollution and space junk are real problems.
It is very exciting times. From a business model perspective what is interesting to me is thinking about how the LONDON<->NYC low latency demand (finance/tickers) will effectively offset the cost for Starlink to offer service in remote (rural) areas; they can do this due to the fact that they are in the same orbital coverage area.

Add on boats & airplanes - and now we really are in the 21st century (not trying to sound glib, I have wanted this for a long time).

:)