this post was submitted on 02 Sep 2024
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Elon Musk-controlled satellite internet provider Starlink has told Brazil's telecom regulator Anatel it will not comply with a court order to block social media platform X in the country until its local accounts are unfrozen.

Anatel confirmed the information to Reuters on Monday after its head Carlos Baigorri told Globo TV it had received a note from Starlink, which has more than 200,000 customers in Brazil, and passed it onto Brazil's top court.

Supreme Court Justice Alexandre de Moraes last week ordered all telecom providers in the country to shut down X, which is also owned by billionaire Musk, for lacking a legal representative in Brazil.

The move also led to the freezing of Starlink's bank accounts in Brazil. Starlink is a unit of Musk-led rocket company SpaceX. The billionaire responded to the account block by calling Moraes a "dictator."

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[–] [email protected] 17 points 2 months ago (1 children)

Nah, Starlink itself is bad, the intention is good.

[–] acosmichippo 4 points 2 months ago* (last edited 2 months ago) (1 children)

what specifically is "bad" about it? I understand people are concerned about space junk, but it seems worth the benefit to me.

[–] [email protected] 5 points 2 months ago (2 children)

It's wrecking astronomy already and we aren't even at the peak of satellite constellations.

[–] [email protected] 2 points 2 months ago (2 children)

Wrecking is not really the right term.
It is causing work for astronomers, and wrecking very few older systems, but generally it is an issue you can work around. I.e. something temporary. What you usually see in my experience of the field is you have some of your work degraded by satellite streaks, which are about 2x more common since starlink, and you understandably complain at starlink. And then get around to coding up a solution to deal with the streaks, spend another few runs until it about works, and eventually forget this was ever a thing.

In more detail, the base issue is, that you are taking an image, with probably minutes or hours or days of exposure, and every satellite passing through that image is going to create a streak that does not represent a star. Naturally that is not good in most cases.
The classic approach here, because this issue has existed since before starlink satellites, is to - depending on frequency and exposure length and your methodology - either retake the entire shot, or throw out at least the frames with the satellite on it, manually.

The updated approach is to use info about satellite positions to automatically block out the very small angle of the sky around them that their light can be scattered to by the atmosphere, and remove this before summing that frame into your final exposure. Depending on methodology, it might also be feasible to automatically throw away frames with any satellite on them, or you can count up which parts of the image were blocked for how long in total and append a tiny bit of exposure only to them at the end.

To complicate this, I think more modern complaints are not about the permanent constellation satellites but those freshly deployed, that are still raising their orbits. Simply because their positions are not as easy to determine, since their orbits are changing. So you need to further adapt your system to specifically detect these chains of satellites and also block them out of your exposures.

The issue here is that you need to create this system that deals with satellite data. And then you need that control over the frames in your exposure, which naturally does not match how exposure used to work in the olden days of film, but to my knowledge does work on all "modern" telescopes.
My knowledge here is limited but I think this covers about 30-40 years of optical telescopes, which should largely be all optical ground based telescopes relevant today. Further, you probably do need to replace electronics in older telescopes, since they were not built to allow this selective blocking, only to interrupt the exposure.

In summary, not affected are narrow fov modern optical telescopes, and in general telescopes operating far from visual frequencies.
Affected with some extra work, would be some older narrow (but not very narrow) fov telescopes, as you now have to make them dodge satellites or turn off shortly, when previously you could have just thrown away the entire exposure in the rarer cases you caught a satellite. This would be software only (not that software is free).
Modern wide fov telescopes might need hardware upgrades or just software upgrades to recover frames with streaks on them.
Old wide fov telescopes may be taken out of commission or at least have their effective observation times cut shorter by needing to pass out on more and more exposure time over satellites in the frame.

It is a problem, yes, but in my understanding one that can be overcome, and is causing the main annoyance and majority of its issues while the number of satellites is increasing, not after they have been increased.
I don't know of a single area of ground based astronomy that couldn't be done with even a million satellites in leo.

[–] [email protected] 1 points 2 months ago

Maybe to add a bit of general context to this, I am not an astronomer but I work in an adjacent field. So I hear a lot of astronomers talk about their work both in private and public.
You don't really hear them talk about satellites often. What from what I gather really wrecks astronomy is light pollution, which has been doubling every few years for a while now and is basically caging optical astronomy to a select few areas.

The worst thing for astronomy in the last century has probably, ironically, been the invention of the LED.

The satellite streak thing is probably a minor point, where newspapers caught some justified ranting of astronomers and blew it way out of proportion.

[–] [email protected] 1 points 2 months ago (1 children)

Sure, professionals can work around it, but for amateurs it fucking sucks.

Its also not just optical astronomy either, they shit out RF on the reserved radio astronomy frequencies too.

[–] [email protected] 1 points 2 months ago (1 children)

Yeah, for amateurs it'll be a while longer for this tech to become easily available.
Though It is also fundamentally fixable, you can take the output of your sensor and apply the same sort of logic to it as professional large telescopes. The blocking spots will be larger since the telescope will not correct for atmospheric distortions and likely be in a less favorable spot, but still you can do far better than throwing out entire frames or even entire exposures.
It is ofc a much much larger ask for hobby astronomers to deal with this initial wild-west software mess of figuring all of that out.

As for the RF mess, this is the first time I hear of that. It seems honestly kinda odd to me, we have a lot of frequency control regulations globally and I have heard SpaceX go through the usual frequency allocation proceedings. A violation of that would be easy to show and should get them in serious trouble quickly. Do you have any source on that?

[–] [email protected] 1 points 2 months ago

Its not radio emissions necessarily, but general EMI, which isn't illegal. But we're talking about such sensitive instruments looking for incredibly faint signals. While the noise from 1 satellite might be insignificant, the combined effects of 100,000+ of all the planned constellations is going to be brutal to the noise floor. It's the same deal with optical astronomy. Bright spots are an issue, but they are also going to increase the general diffuse brightness (noise) of the night sky, which is already reaching 'problem' threshold with the current number of satellites.

https://www.aanda.org/10.1051/0004-6361/202346374 https://www.nature.com/articles/s41550-023-01904-2#Sec2

[–] [email protected] 1 points 2 months ago (1 children)

If I had to choose between global high speed internet access, and ground based astronomy, I'd pick the Internet every time. I'd completely blot out the sky forever if that's what it took.

We don't need ground-based astronomy to learn about the universe, I'd rather encourage more space-based astronomy. Or build some observatories on the moon if you really want to build on a solid space body.

However, Starlink is a for profit company run by Elon Musk. I don't really want them doing it, because they're not going to provide unlimited global Internet to everyone. So as the guy said, the idea is good, but Starlink is bad, although it is currently the only such option.

[–] [email protected] 1 points 2 months ago

Do you know what the price difference is between a ground based observatory and a space based one? We are talking orders of magnitude in differences. It took an international alliance just to build the ISS in low Earth orbit. We are decades away from being able to build anything on the moon, and we definitely won't be building visual telescopes there.