When an individual transmits on a band they shouldn't the FCC issues a fine. When a company transmits on a band they shouldn't the FCC gives them the band.
> "When a company transmits on a band they shouldn't"
The source article is quite clear there's no regulatory violations here.
> "Although this IEMR abides by ITU-R guidelines, these intensities are large compared to the strongest astronomical radio sources in the sky and will therefore have the potential to disrupt astronomical observations at SKA-Low frequencies;"
> "The detected IEMR and UEMR are outside of the frequency bands protected for radio astronomy, but are at frequencies of great interest for key experiments for the SKA-Low facility, and at frequencies where RQZ protections at the SKA-Low site are in place;"
The source states that the UEMR SpaceX causes in this spectrum is currently not regulated but interferes with astronomical observations.
The claim stands whether a regulation will be put in place which will require SpaceX to fix or switch off their (thousands) of satellites polluting the spectrum or the band will simply be handed to SpaceX.
"This UEMR is not currently regulated by the International Telecommunications Union (ITU), the organization responsible for managing and allocating the radio spectrum for various uses"
Lots of things interfere with astronomical observations - if someone builds a house, it'll interfere with their neighbors observing a star close to the horizon.
Especially since the observations appear to be outside the protected spectrum, the answer is "that's probably okay". There's balancing that needs to be done - does the safety benefit of a world in which nobody can be out of contact of emergency services, and the economic benefit of having reasonably high speed internet available everywhere, outweigh the loss of radio astronomy potential.
The long-term balancing is whether humanity can take over Earth's orbit and build out advanced technology there, or not. I think in the long run, radio astronomy is the one that will have to bend. If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space, there's no reasonable way to adapt to that—it's unreasonable to ask an entire planet to turn into a radio-quiet zone over its entire orbital shell. Intentional broadcasts are one thing—that's what spectrum licensing regulations are for. Minor EMI is a bridge too far.
Further context: the signal strengths they're talking about are equivalents of isotropic emitters in the *milliwatt* power range, detectable down to the microwatts—detectable at ranges of thousands of kilometers,
> "The flashes reach a maximum intensity of approximately 10^6 Jy beam^−1 at ranges of ∼500 km (EIRP ∼ 30 mW) and a minimum intensity of approximately 2000 Jy beam^−1 at ranges of ∼2000 km (EIRP ∼ 1 mW)"
Further context: part of the EMI isn't a fixable circuit design issue—it's (I understand) EMI from normal operation of ion thrusters,
> "The authors have been in communication with SpaceX (who owns, builds, and operates the Starlink constellation), who explains that this radiation is likely due to the satellites’ propulsion or avionics system and is likely over 50–200 MHz (SpaceX 2023, priv. comm.) The propulsion system is actively engaged during the time this train is detected. This radiation is therefore in the class of UEMR."
> If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space [...]
Well, that's what is required to receive a weak signal from beyond that circuit board, from outer space.
> there's no reasonable way to adapt to that
You'd be surprised what becomes reasonable and possible once a requirement is set.
> it's unreasonable to ask an entire planet to turn into a radio-quiet zone.
Noone is asking that.
It's reasonable to require radio interference of a device to stay within defined boundaries. This is the case in all other industries as well, why shouldn't it suddenly apply for a fleet of satellites which blast radio signals from outer space to earth?
> "This is the case in all other industries as well,"
No; it really isn't. There's no industry on the planet where "must accept" regulations are set by the world's most sensitive physics experiments.
Do we set acoustic noise regulations by what a LIGO interferometer can measure? Of course not. We'd have to outlaw the mechanical engine were it so. Regress to a medieval society of horse people (very small horses with noise-absorbing horseshoes).
Do we regulate nuclear power by what astrophysical neutrino detectors perceive? Also, no. Even though they see fission reactors on the other side of the planet, and it is noise to them.
The prior art is we that set noise regulations by what interferes with actual humans in their actual day-to-day functioning; and we set RF regulations by what interferes with the functioning of other circuits useful to humans. Not exotic physics experiments. This is a new thing to ask; and it is bold.
> There's no industry on the planet where "must accept" regulations are set by the world's most sensitive physics experiments.
The criteria is not industry vs. "world's most sensitive physics experiments", it's industry vs. "agreed activity for public/societal benefit". And there are many examples for it.
We regulate light/noise and other pollution in consideration of wildlife and plants, we regulate nuclear waste disposal considering our responsibilities to the greater public good.
We could also not regulate anything with regards to wildlife and plants, there is no immediate economic benefit to preserve all variants of rhinos, tigers, reptiles etc., we could kill all plants except the most resilient one, it's much more economic to maintain them in long-term then.
We could also globally agree to dispose all nuclear waste in one place on earth and just never go there again.
Actually we could disband entities like the EPA, because we can figure out solutions to each environmental impact on-demand if there's enough incentive for it.
But we don't, because there is (or used to be) consensus that there are also goals beyond short-term economic growth. Areas of interest for greater society, for mankind if you will.
> You'd be surprised what becomes reasonable and possible once a requirement is set.
In that case, I'm not sure why you're concerned. Let's flip this around: set up our regulations to loosen our EMI radiation restrictions & facilitate our satellites and space exploration. According to your logic, that should be perfectly reasonable to astronomers, if that's what the regulations say, and it should be possible for them to adapt to that.
If that's not what you meant, then astronomy needs to make some concessions.
Sure, that's also a solution. The public then needs to provide more taxpayer funding to perform such research in orbit of earth. Whatever is preferable in the larger picture of public/corporate interest...
That’s a very different proposal- unless you’re intending to amend your previous statement to:
“You'd be surprised what becomes reasonable and possible once a requirement is set [and additional funding is allocated to overcome the negative consequences of said requirement]”
No need to amend, it's the same, the required funding is a factor to determine how reasonable an investment is. For both parties.
It is then up to the taxpayer to define whether the path of performing astronomy research in orbit of earth to preserve a for-profit business-model is more reasonable than defining regulation which allows such research to be performed on earth for a fraction of the cost (but may require for-profit companies to further invest in R&D to comply or re-evaluate their business model).
It's that simple. Astronomy won't be able to provide immediate ROI or a sales-plan of increased revenue to offset the cost-increase when researching in orbit. So if that's the only criteria, then such research is a futile activity and will be stopped.
Astronomy research?, Radio spectrum?, LOE?, Starlink operations?
All of this is global. In the end it'll be about geopolitics, although it should be a field that urgently requires global governance and consensus.
Next time it could be interference between Starlink vs. a Chinese for-profit. It would be good if there's a commonly agreed way of handling such matters in place...
If astronomy is not able to cope with additional regulation without additional funding, then for-profit companies should not be expected to do so either. It's that simple.
> Astronomy won't be able to provide immediate ROI or a sales-plan of increased revenue to offset the cost-increase when researching in orbit.
That's too bad. I was under the impression that "You'd be surprised what becomes reasonable and possible once a requirement is set."
> If astronomy is not able to cope with additional regulation without additional funding, then for-profit companies should not be expected to do so either. It's that simple
So your belief is that for-profit companies should not be required to comply to regulation put in place after they start business in any field.
And for-profit companies who later join to compete with them? They should, because it's not "additional"? Or also not, to ensure a competitive market?
So basically no regulation of any kind shall happen, because companies should not be expected to cope with new regulation if it incurs additional effort for them.
> So your belief is that for-profit companies should not be required to comply to regulation put in place after they start business in any field.
That is not what they said. That's an extremely bad-faith statement that's not even a "misinterpretation", because that implies that there is a valid interpretation, and there isn't - you just made up something completely different and claimed that they said it.
You're really not helping your argument here if you have to resort to lying about other peoples' words in order to try to defend your positions.
Humanity doesn't own SpaceX. If humanity would have a vote on this I'd be happy to agree with you but it is just one US corporation that does this and they don't get to decide for all of us. If they just did their thing above the USA that would be another matter entirely but that's not how this works, as you well know. So you slip in the 'for the greater good' argument that does not necessarily hold and besides which isn't up to SpaceX to decide, especially not unilaterally.
> "but it is just one US corporation that does this and they don't get to decide for all of us"
I don't understand your comment on so many levels. The ITU treaties do exist, and they do protect observational astronomy bands, and everything here is *in compliance with* extant ITU regs. As I quoted above. I can turn your words on your head: who are astronomers to make arbitrary choices for rest of the human species? Or, who are HN to? People do want their gadgets to work. They value that more highly than many things, things more important than mere astronomy experiments—more highly than human rights, for example (to contemplate all the slave labor in the modern electronics supply chains).
On another level: you say it's just one one company, but that company is obviously just an early-adopter, leading-edge of a great horde of space companies going in for the gold rush. There will be many others, and then there will be the Chinese military, and—do you think there will be more favorable outcomes negotiating with the PLA, filing complaints to the PLA over the RFI of their prized military assets? Yeah; no. In 5-10 years the landscape will certainly be utterly unrecognizable, and it will not be a SpaceX hegemony any longer. You will be opposed to a hundred adversaries of many nations—not just that one.
And following after that, there will be humans and human tourists going up, pretty soon I'd bet; by the thousands; and they'll be bringing their electronics gadgets up to visit, and later inhabit, Earth orbit. Have you internalized the numbers we're discussing here? This telescope array can detect the equivalent of a short-range wireless Bluetooth gadget at 2,000 kilometers range—and they're complaining about it, they want that banned. (Literally—if it weren't for the earth in between us, my wireless mouse right here could be radiating greater signal power through your body, dear reader, no matter where you are right now on the planet, than these satellites flashes we're discussing here. Click, click.) No way is that compatible with a future of humans inhabiting space. The space RF environment is, incomprehensibly pristine as it stands... but that won't last, can't last, there's no way humanity moving to the stars will preserve that pristine silence, you might us well give up right away. Fighting it is futile, foolish, misguided, and more than a little misanthropic.
> If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space, there's no reasonable way to adapt to that
They also mentioned detecting narrowband transmissions from a commercial FM station, 300km from the radio observatory that reflected off the satellite.
Which, like, cool that they can detect that, but you completely lost me if want to ban all metallic objects in earth orbit.
(Here's a historic irony: the field of radio astronomy was founded by people doing this stuff. The cosmic microwave background was discovered, by accident, with an RF horn built for this satellite relay experiment).
(Here's another weird one:)
https://en.wikipedia.org/wiki/Project_West_Ford ("Project West Ford" (1961-63)) ("The goal of the project was to place a ring of 480,000,000 copper dipole antennas in orbit to facilitate global radio communication")
Just send up a satellite that uses solar power to spew out sticky dust to cover everything metallic. The dust would be fairly efficient, as it would continue to orbit and stick to things over time.
Yes, this could cause problems, like loss of GPS, weather prediction and other scientific equipment, and enemies wouldn’t be able to keep an eye on each other as easily, leading to wars. But, maybe light pollution would be less annoying.
> There's balancing that needs to be done - does the safety benefit of a world in which nobody can be out of contact of emergency services, and the economic benefit of having reasonably high speed internet available everywhere, outweigh the loss of radio astronomy potential.
If this balancing argument is merely based on short-term economics, then of course the corporation always wins. Every commons becomes a tragedy in that world.
There are existing regulated bands for astronomy, which already shows the regulatory bodies don't just consider short term gains. The person you quoted weighs it against outweighing the loss of radio astronomy potential, saying much of the same. Who is this note about needing to compete with short term economic gains responding to?
Well, sure, but "regulatory bodies update spectrum regulations for the common good" is a lot less charged a claim. It was the other specifics (breaking current regulation, treatment based on whether you are an individual or a company) that were contentious, not the resulting assignment itself, and at least half of that was clearly false.
Within the system the FCC is (putatively) operating under, they cannot fine someone for something they have no regulatory jurisdiction over. Congress could fix that pretty quickly if they wanted to, of course.
How is the whole Musk/Trump love affair going today?
The FCC doesn't enforce very strongly, mudduck and others like him have been killing CB channel 6 (and sometimes 19) for like 2 decades and nothing has been done nor will be done.
Which is exactly why I shared it. There is a clear pattern of corporate interference on public bands and a pattern of FCC enforcement being applied to individual interferers.
If they want to serve the U.S. market, which they do, they still have to deal with the FCC and comply with U.S. regulations, regardless of the launching country.
Mitigation is going to be the name of the game. Whether they like it or not, low earth orbit (LEO) is becoming a very busy place and it's not just SpaceX launching lots of little satellites there. The Chinese are very busy launching their own satellites into LEO. And there are other companies and countries doing or considering the same. Spacex and Star link get most of the attention; but the Chinese are doing a decent job to keep up with them in number of launches. And there are a growing number of companies with LEO launch capability.
Mitigation might have to involve some sacrifices. I don't see how policy is going to be able to mitigate much here. And of course the Chinese are under no obligation to listen to US policy makers. They might have their own debates domestically around this topic and they might be reasonable about the topic internationally even. But building international consensus; or even enforcing what little there is on that front could be challenging.
A more practical approach might be accepting that earth based observations are inevitably going to suffer a bit as the number of satellites grows from thousands to tens of thousands and eventually well beyond that. Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware. That's already happening of course. And otherwise, astronomy is very interesting and cool but mostly it concerns observations about things that are really really far away and not directly relevant to a lot of things on earth. Unless of course the thing under observation is on a collision course with us.
With privatization, the public is paid something. Whereas StarLink's use of LEO is a taking. They're denying others open access usage. Without any possibility or threat of consequences.
"Use" is such an inadequate term, but I couldn't think of another. Commandeering?
> “We” as in the select few countries that have the launch capability and the space tech.
There has never been more access to space-based imagery and other sensing. With multiple companies selling this stuff ever cheaper. Every news outlet can now afford to buy images. And that's because of cheap launches.
The RF spectrum is a public good in the US and there are requirements placed on the winners of those auctions to demonstrate it provides some public benefit. A company can't just buy spectrum and sit on it, for example. They must use start to use it in a certain timeframe.
The RF spectrum is a common good, not a public good. Public goods are non-excludable and non-rivalrous. The RF spectrum is non-excludable (anyone can transmit on any frequency, given the right equipment) but rivalrous (transmitting on one frequency prevents others from using that frequency).
Requiring the winner of a spectrum auction to use it is a way to prevent anti-competitive tactics (since the government is granting a monopoly to the winner). The goal is to incentivize productive use of limited resources, not necessarily to benefit everyone. In theory, the winner could use the spectrum for entirely internal purposes. Though in real world spectrum auctions, the government usually has stipulations such as requiring interoperability or using open standards. This reduces the value that the government captures, but likely increases the value that is created overall.
Before spectrum auctions, the government simply mandated what frequency bands were used for what, and by whom. Getting access usually meant lobbying and back room deals. Sometimes the FCC used lotteries, which caused speculators to enter lotteries and then license access (basically capturing revenue that would have gone to the government had the spectrum been auctioned). In practice, auctions are the worst form of spectrum allocation, except for all the others.
This seems circular… since the lack of a worldwide authority, that can decide the value of X public good is worth more than zero, is the issue in the first place.
A bit, it's 5 orders of magnitude over the required SNR?! From the article: "The authors estimate a lower limit of 93 Jy per beam in the frequency averaged images containing Starlink emission. Considering just 1 mJy of radio frequency interference could mess up an EoR power spectrum integration, this could severely affect SKA-Low EoR science."
My point here was not to contest that but make the point that the cat is out of the bag and that it is indeed impacting SKA-Low EoR science and the people involved with that have to deal with that.
Getting the cat a little bit back in the bag via policy and other means is maybe worth trying (good luck) but I don't give it a very high chance of success.
This makes me want to say "is nothing sacred?!" I get your point from a pragmatic: this is the world we live in, work with it, not against it.
I think you need to scope this approach when suggesting it though, since it's effectively "a policy has been broken by a company, but we can't undo it, so lets just accept it and let them get on with it" which doesn't seem like it'll lead to a better world.
I do agree with your point that the people who suffer from the policy breach have to be pragmatic in their handling. But ultimately, let's not let pragmatism and stoicism lead to businesses spectacularly breaking policies in hopes of being told "well the cats out the bag now, the victims can deal with it, you might has well continue".
> I do agree with your point that the people who suffer from the policy breach have to be pragmatic in their handling. But ultimately, let's not let pragmatism and stoicism lead to businesses spectacularly breaking policies in hopes of being told "well the cats out the bag now, the victims can deal with it, you might has well continue".
I fully agree, and that's IMO the core-issue here: This strong-arm approach of just forcing the problem to be solved in your favor by scaling as fast as possible and then pleading how uneconomic it would be for you to change course, insisting that the other side should be pragmatic about this.
I don't remember this was a working strategy in the past (imagine a car-company just accelerating sales of a faulty car to scale THEIR issue and avoid having to do a recall), but nowadays it could even be turned into a geopolitical topic...
I instinctively want to agree with you here and bemoan the state and directions of the world. But if I really think about it, it's been happening my entire life. I'm mid 30's now. I assume someone older than me would have had the same experience of it happening their entire life.
You're right though, it's crappy and merits a lot of geopolitical reflection. But I suspect it goes back millenia and is a manifestation of basic evolutionary biology with the business world, rather than anything that can be solved/fixed.
And we've gone full circle about the balance of working for/against humanity in the name of progress.
The EPA is only two decades older than you, and it enforced a bunch of brand new regulation on all the existing companies. There used to be a willingness to actually govern rather than cede everything to corporate interest.
I'm a bit older now, and while there has always been corporate meddling in public decision-making (which is unavoidable and also somewhat needed to help steer the boat a bit in some situations), the economic effort a company has to invest rectify wrongdoing mainly shaped the amount of spending for legal counseling and lobbying, but it didn't directly shape a ruling.
Today, environmental/privacy/safety laws are suddenly not that strict anymore, because now we naturally need to also take economic interests of the violating company into account.
So you might end up in a situation where an official body will officially rule that the harmed party may be right, but needs to be pragmatic about its needs just because of the increased inconvenience it would create for the opposing party if THEY would have to change their way.
In my experience, this was not the case 15 years ago.
It’s the definition of ‘too big to fail’, and it’s been a viable and effective strategy… for ever? Near as I can tell. He’ll, the Fed even got created because of the time the whole US economy cratered in the early 20th century and one man was the one whole bailed out the whole country.
Given that the offending entity is owned by the world's richest man certainly their 'pleading how uneconomic it would be for you to change course' should be dismissed instantly without a second thought.
Someone, if we stretch that metaphor, intentionally opened the bag for profit. We can and should hold them accountable.
> the people involved with that have to deal with that
Yep, and they should hold the people who caused this accountable.
> is maybe worth trying (good luck) but I don't give it a very high chance of success
You may be correct that it has a low chance of success. However, people who think like you are exactly the cause. People who value Musk's net worth more than science, people who fetishise "progress at all costs," regardless of whether or not the progress actually helps people or is what makes sense (municipal internet, folks!). Understanding physics is also critically important progress, but it doesn't make money next quarter so you don't care.
So you'll forgive me if I don't take your advice on the situation.
> "The Chinese are very busy launching their own satellites into LEO."
The Chinese (correctly) view these satellite constellations as a key military capability, and have gone all-in on creating their own version. (I mean, I don't see how that's even debatable at this point—having seen the influence of Starlink in Ukraine. Future conflicts will only amplify the gap between the haves and have-nots).
They haven't yet launched a large number (~120); they don't now have the launch volume for large-scale satellite constellations. Their race is to first catch up in launch capability. They have dozen private startups—heavily subsidized and favored by the state—in the race to build a viable, reusable launcher comparable to Falcon 9, that they would then use to launch Starlink-like constellations at the same cadence.
I'm not clear why not. The scale of the completed SKA-low (512*256 = 131,072 antennas, 1.8 meter lengths) is the same as that of Starlink itself. It's even less mass; the antenna parts alone, they are wire dipoles, they say they only weigh 1.6 kg each.
It's just nowhere near feasible. Each element would need power, orientation, precise positioning and a data link to the processing stations. For SKA low the raw data rate from all antennas is something like 2 Pb/s. Which is more than all of Starlink combined. Which is massively stepped down to 7 Tb/s by the central processor, a supercomputer with purpose built signal processing hardware. Then the next stage takes it to 100 Gb/s. You would likely have to transmit the data via radio links, which would defeat the purpose of going to space. When a radio telescope is built in space it will likely be on the Moon (or in orbit), designed for lower frequencies and much less ambitious than SKA low.
I still don't understand the case; sorry. Actually, we're not working with the same set of facts seems to the main thing.
> "would likely have to transmit the data via radio links"
No; you'd use free-space optical communication, which doesn't interfere at all, and which Starlink has pioneered. They have working laser links at 200 Gbps, per link,
The optical bandwidths potentially accessible, in vacuum, are much wider than that of microwave links to/from Earth.
> "a supercomputer with purpose built signal processing hardware"
I don't see why couldn't put that in space, today. That SKA signal processing system you're talking about amounts to 100 petaflops, drawing 2 MW of power. That's far less power than Starlink already has in orbit right now (somewhere in the 10's of megawatts). It's even within a factor-of-10 of raw compute—the figures I found say each V2 Starlink has 1.2 TFlops of local processing.
I don't understand why it'd be impractical to put an equivalent signal-processing system in orbit. At any rate, there's YC startups getting funded for space-compute proposals more ambitious than that,
Laser links would make everything more complicated and expensive. Radio antennas can share the same hardware to link with many terminals, not so with laser systems. They are point to point, so you need many more. They also require precise pointing, you can forget passive spacecraft. The number of 42 PB per day is about three orders of magnitude lower than the data rates required by SKA Low.
>I don't see why couldn't put that in space, today.
Because the electronics are not built for space. Space rated electronics is about a decade behind their ground based siblings. Radiation is one of the most problematic, degrading electronics and disrupting digital memory. You also need petabytes of temp storage. Which, again, doesn't exist. For reference, JWST carries a 70 GB solid state recorder, I think Roman has about 1 TB. Then there is all the cooling, which is difficult in space. Saying there are some start-up considering computing is not the same as it being possible to order a system like this today.
The question is not could it theoretically be done, but can it be done on even the sorts of budget of a space science mission. And the answer to that is no. SKA pushes computing and technology to the limit on the Earth, where these things are much more advanced.
Geosynchronous satellites could give us even longer baselines couldn't they? Or even at l4 and l5. They don't get shielded by the earth like l2, but the station keeping would be easier. That would be a massive baseline
Baselines are one thing, you need a huge collecting area to get useful sensitivity, which there is barely budget for to build on earth, let alone in space
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware.
Honestly once Starship is operational SpaceX should subsidize launches of non-commercial astronomy hardware. Could build some goodwill to offset the negatives.
No , regulation. That’s what is necessary for cars, planes etc , otherwise the competition would lead to low emission cars . Plus the space debris creation , which is also unregulated , but threatening humanity - for profit
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware. That's already happening of course.
Seems more effective for astronomers to embrace it. Perhaps by getting SpaceX to add a few dozen hundred satellites kitted out for radio astronomy. Link them together and it could be amazing for radio astronomy!
How do the various LEO constellations mitigate band interference issues? Does the US/China have some agreement as to which bands their respective countries' companies will use?
Ah, the techbro defence. "We already started doing it, so I guess you're just going to have to let us".
> Whether they like it or not,
A swarm of LEO satellites because in the current political climate it's easier to massively pollute orbits and prevent astronomy than do municipal internet is not, in fact, a law of nature; nor is it inevitable.
> But building international consensus; or even enforcing what little there is on that front could be challenging.
Ah, a challenge! Let's all give up immediately; this could make some rich people a lot of money, after all!
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware.
Would you like to pay for launching Vera C. Rubin (8.4m, nearly 20,000kg for just the camera and mirrors) into space? How about the TMT (30m, expected ~2.6 million kg)? Truly spoken like someone who knows nothing about astronomy.
> And otherwise, astronomy is very interesting and cool but mostly it concerns observations about things that are really really far away and not directly relevant to a lot of things on earth.
Apparently fundamental physics is not very relevant to us here on Earth! This is one of the most small-minded statements I've ever read.
There is no royal "we" that "has to" do anything. There's just groups of people and countries making use of a shared resource, LEO.
Your underlying question as to why some of those are launching satellites is much easier. They are apparently quite useful for things like communication, providing internet, etc. And people are willing to pay for that kind of stuff. It's not more complicated than that.
Why do we need radio telescopes. Satellite communications are infinitely more useful for people on earth than some research papers about things light-years away
Because they provide data that other types of telescopes do not. We have X-ray telescopes. We have infrared telescopes. We have optical telescopes. Also as a bonus, for ground based radio telescopes, we can use them 24/7 instead of waiting for nighttime.
Yes, but if it hadn't been for the efforts of visionary scientists at NASA trying to reach the stars, there would be no means of putting those satellites into orbit.
The point is basic science (e.g. radio astronomy) is, if not necessary, then highly desirable, because it can lead to unimaginable advancements in humanity (or in a country’s technological and military capabilities if that’s how you think).
Sure, and industry is also valuable and contributes to progress. I don’t think it’s useful to say one must always take priority over the other regardless of specifics.
Ironically, those satellites would not be able to communicate effectively without the understanding of relativity that was obtained by looking at things light-years away.
Einstein developed relativity from mathematical reasoning. A major influence was the michaelson morley experiment, which was solely done on earth. Relativity was developed in the early 1900's and the first radio telescope was made in the 1930's. Also, orbital mechanics uses mostly Newtonian mechanics and the communication of satellites is radio waves which were understood way before einstein. There is no relativity involved. Literally everything you said is factually incorrect.
Satellites experience time dilation because of their orbital velocity and gravitational field being significantly different at their altitude. Without accounting for this, the clock drift would become unmanageable and Newtonian models are insufficient to correct for it.
You're right that the majority of Einstein's theories were ultimately thought experiments but getting the parameters correct involved a lot of measurements and experimenting, to get to where tech like GPS and StarLink can be accurate. We were also looking at far away stars for centuries before Einstein so that he could have the environment for his ideas to be discussed, which I was including in my phrasing "looking at things light-years away."
I wasn't saying it to start an argument, though. I wanted to counter the rather dismal view of "why do we need radio telescopes."
Einstein developed a theory that includes General relativity and special relativity. Experimental results confirms both of them, with special relativity being the easiest one to understand the consequences of. Without experimental confirmation, neither theory would be valuable.
Communication requires accurate timing. Time dilation occurs between Earth and satellites, a phenomenon that isn't part of Newton mechanics, so relativity is indeed involved.
"We" don't have to launch anything at all. SpaceX needs to launch enough satellites to satisfy customer demand for their constellation. In general the trend actually is that SpaceX is launching fewer but larger satellites (initially they were doing 60 satellites per launch, but they made them larger and now launch 24-28 satellites depending on the orbit inclination.
You should also ask why do we have to do this particular research? Both parties are impacting this particular band of the spectrum. One by excluding others and the other by radiating in those frequencies.
Excluding others only in a way that is not dissimilar to you locking your doors/windows to exclude others from freely entering your house.
Yes, some of the premiere radio observatories have radio transmission exclusion zones around them, but they are also typically away from that exclusion zone impacting as few as possible. Starlink on the other hand is not attempting to do anything of the sort. It would be interesting of Starlink could respect a geofence kind of idea so that they stop broadcasting when over certain areas, especially since they do this over geopolitically exclusion zones.
If you think the internet is a big deal, you haven't run into how happy the military is to have high bandwidth low-latency communications anywhere on the planet.
Starlink is nothing compared to the value Starshield provides, and the civilian product drives costs down.
With drone warfare being the next thing, the US probably can't afford to not have a company running a major LEO ISP.
As others have said, because it's a key military capability.
Humanity is what humanity is, not what we wish it'd be, so key military capabilities need to be developed or you get razed by the guy who did develop them. Doubly so now that we've rediscovered that culture is much more resilient than we'd thought, and that different people want Earth to look in different ways.
Do we all wish we'd stop ecological collapse instead? Yeah. But it's not going to happen so it's irrelevant.
Because the speed of light is slow and orbital mechanics can’t be changed.
To have internet everywhere you need to either accept bad latency (300-500ms round trip) or have closer satellites, which means they’re moving faster, which means you need more of them.
If we had a trusted powerful peacekeeper with a track record then we wouldn't need to. But now that masks are off everybody is busy launching dual purpose sats and whoever launches the least can literally get nuked from orbit if they don't do whatever the guy with more sats wants.
Then whoever has the most sats will say "that's it guys, LEO is full and you need our approval to launch more" and if someone raises a stink you guessed it, they can get nuked from orbit
There are no kinetic NOR nuclear orbital strike capabilities for anyone right now, nor is anyone really working on it either, because it just makes zero sense (primarily because suborbital launches achieve the exact same outcome for a tiny fraction of the cost).
Wouldn't having them already up give a lot less warning in a first strike situation? Also redundancy if all your subs, silos, and bomber bases got hit first by their satellites. It doesn't even have to be rational though, combinations of graft and brinkmanship would be enough. It seems really optimistic to think they haven't all already done this.
> Wouldn't having them already up give a lot less warning in a first strike situation?
Improved first strike capability is worthless íf it isn't crippling, and "devastating enough" first strike capability from orbit is completely unaffordable, and impossible to build up unobserved.
Being in orbit is a hindrance more than anything, really, because maintenance becomes ruinously expensive, everything is trivially observable for all your adversaries and you have to align the orbit with your target beforehand, too (which, again, everyone can observe).
> It doesn't even have to be rational though, combinations of graft and brinkmanship would be enough.
Enough for what? Threatening to nuke some satellites? Because anything else you can do easier, cheaper and on a larger scale from the ground. Why would you bother with nuclear warheads in space when you can just build/maintain like 10 ICBM silos for the same cost?
> Wouldn't having them already up give a lot less warning in a first strike situation?
From GEO, no. From LEO, still probably no.
There may be a bird positioned just right so a small deörbit burn pots Moscow quicker than an ICBM could. But the moment you start burning, you’re caught. (Same as an ICBM.) And unless you have a really obvious orbital configuration that bunches a bunch of birds in a way useful for practically nothing but such a strike, you only get one or two such “early” shots before a wall of ICBMs would have landed.
Nukes in space aren’t about nuking the ground from space. It’s about space area denial through EMP.
"Elements within the Soviet space industry convinced Leonid Brezhnev that the Shuttle was a single-orbit weapon that would be launched from Vandenberg Air Force Base, manoeuvre to avoid existing anti-ballistic missile sites, bomb Moscow in a first strike, and then land. Although the Soviet military was aware these claims were false, Brezhnev believed them and ordered a resumption of [satellite destroyer] testing along with a Shuttle of their own."
The exact claim might have been false, but at least i theory it could do this maneuver from orbit - e.g. during a regular space hab or satellite lunch mission it could dipp into the atmosphere, do a rapid oebit inclination chang using its wings, then boost back to orbit using the OMS. Next thing it would deliver the "totally science experiments" on the way to their targets once comming over the horizon. Maybe it could then even do the manuever again to either regain the old orbit parameters ir at least reach a more surivable random other one.
> at least i theory it could do this maneuver from orbit
Nukes from LEO aren't impossible. They're just impossible to do better than the current triad. Any breakthrough in propulsion that would make a plane change easier or less visible confers the same advantages to an ICBM. There is a narrow window in which orbital nuking can outperform, and that's almost entirely taken care of--and exceeded, in stealth--by SLBMs.
Nuking from orbit was not literal. The point of sats is intercepting. Sats allow you to nuke the other guy while intercepting his rockets. Same result...
> Wouldn't having them already up give a lot less warning in a first strike situation
No. Your missiles have further to fly from geostationary orbit than a missile silo on the ground, not to mention the additional complexity of designing your ICBM for reentry
I don't see big potential for the current US government to value scientific interests higher than the interests of SpaceX.
Wouldn't be surprised if SpaceX just continues to launch such satellites causing unintentional interference, to then claim in case of escalation how uneconomic it will be for them to correct this issue now and how the financial impact to SpaceX needs to be valued higher than scientific needs.
This LEO Direct-to-cellular strategy seems to play out similarly, with SpaceX launching massive amounts of satellites which are technically not capable to prevent interference on private spectrum while crossing country-borders, so ITU/FCC/CEPT now need to find a solution to deal with this situation.
Spite about what? Elon hasn't done a single thing to harm the administration. The bill he claimed to dislike passed easily, he stopped talking about Epstein as soon as it seemed like it might cause actual problems for the president, and in the past couple days he's expressed very vocal support for the Texas gerrymandering effort and domestic deployment of the military in DC. He continues to be the administration's most powerful and influential supporter in the world.
They've made up since, with a plan to use the drama and outrage to disparage and prosecute political opponents of the President. Congress and Trump-appointed judges seem to be acting in support of that approach so far.
Musk and Trump have agreed a detente. We have no signs of them helping each other. Where Musk has made up is with the GOP machine, particularly in the House. That looks less like alliance than positioning.
> Wouldn't be surprised if SpaceX just continues to launch such satellites causing unintentional interference, to then claim in case of escalation how uneconomic it will be for them to correct this issue now and how the financial impact to SpaceX needs to be valued higher than scientific needs.
At least Starlink satellites need to be replaced every few years anyway due to their low orbit. That is a natural ceiling for economical questions - ITU et al take years anyway until anything is actually enforceable, so SpaceX has ample time to prepare should there be a relevant movement in ITU.
The company I'm working for has its own EMC chamber (maintaining that huge room fully calibrated and standardized is ultra expensive... just looking at these EMC test receivers that go up to 40GHz my me cry in $$$$) and we invested giant engineering effort into our products
to be far below every radiation limit norm in the world.
Shouldn't satellite companies have even better stuff and more strict regulations or are these unintended effects maybe caused by the harsh environment?
Most communications satellites (which is all Starlink really is) are heavily focused on their operating bands and any specific bands they are told not to interfere with so they can get launch approval. There's no benefit to doing anything extra. And not only do they have to be told which specific bands they can't interfere with, the government actually has to require delivery of test results or else that is the same as giving permission to interfere.
Most companies won't spend a penny, take a second of time, or add a gram to a satellite if it doesn't affect their mission or chance of approval. Especially not one as cost-optimized as SpaceX. They won't change a thing unless the US government forces them to do so, or if they think that a government order is imminent so they come to some voluntary agreement ahead of time to avoid what would probably be a more constraining official regulation in the future.
The actual issue is probably caused by switch-mode power supplies or some digital signal on the satellite that isn't fully shielded, possibly one that does digital control of a motor or thruster. It probably isn't the communication radios since they operate at a much higher frequency. You can fix the issue by adding filtering and/or shielding, but that takes extra components (meaning extra cost and weight) and requires testing (meaning time). Plus you have to identify the offending system, which means you have to start with testing and detective work. This interference was only detected on some Starlink satellites, so you have to do detective work to find out if it is a particular operating mode or generation of satellite that is offending, do testing to confirm it, and then work on a fix.
This is actually not correct for Starlink. They did a lot of work to lower their albedo based on astronomer complaints, even though there wasn't any government regulation in this area.
It might apply to some of the emerging Starlink competitors however, especially the Chinese ones and AST.
The albedo reduction they worked on is the exact reason why I wrote this, "...or if they think that a government order is imminent so they come to some voluntary agreement ahead of time."
SpaceX only "voluntarily" did that because the government was likely to put more stringent requirements on them if they ignored the complaints.
I'm not sure why they're complaining when the SKA isn't even active yet. Once it's active Starlink will do just like they have for other radio telescopes, avoid transmitting while they're in the boresight and in general don't transmit toward the antenna. This is a well practiced interaction at this point with scientific agencies in multiple countries.
The only thing that they can't stop would be things like reflected unrelated ground communications off of the satellite, but that would be very weak.
> avoid transmitting while they're in the boresight and in general don't transmit toward the antenna
Not sure this will help against the mentioned unintentional electromagnetic radiation (UEMR) likely caused by the electronics of the satellites themselves.
"This radio emission at lower frequencies from Starlink isn’t their downlink frequency, but instead unintentional electromagnetic radiation (UEMR), thought to be caused by the onboard electronics of the satellite."
One interesting complication is that it seems the propulsion, the electromagnetic ion thrusters, are one of the sources of unintended emissions,
> "Communication with SpaceX engineers suggested the UEMR originated from the propulsion/avionics system of the satellites as they were orbit-raising at the time of detection."
That's quite a big deal actually, if the propulsion system is the major source of interference. Firstly the propulsion system's operation is infrequent (at least at individual satellite level, although if you've got a constellation as big as SpaceX's you'll have satellites doing orbital transfer somewhere a lot of the time). Secondly it isn't a critical part of SpaceX's tech, and other solutions exist for future Starlink generations which wouldn't compromise its service offering at all. Of course interference from a propulsion system is also less directional and tweakable...
They use a high efficiency low thrust hall effect engine - for those kinds of thrusters you might have to run it continuously, possibly continuously to ballance out the atmospheric drag at low altitude. For normal chemical thrusters you indeed use the for just a bit very occasionally (or else you run out of propellant very quickly).
Still I agree it is fixeable - they can tune the hall effect thruster on newer sats to not radiate in this band & avoid running the thrusters when in the field of view of that one radio telescope at the times it is operating.
They're not running thrusters continuously except during orbital transfer. Otherwise they'd run out of propellant pretty quickly even with a HET, and operating smallsats at 559km doesn't require that much orbital correction. They probably fire them far more often for conjunction avoidance than station keeping, but again that's a reported 300 total manoeuvres per day across 8k satellites, which gives them a bit of scope to time them for when they're unlikely to upset regulators
Uh, given there's been radio telescopes there for longer than starlink has existed, I'm not sure why they haven't stopped broadcasting in that area then.
It's possible they haven't requested it yet. I've only heard SKA complaining loudly in the media while American radio telescopes have very obvious blackouts visible on SpaceX's map because they've requested them.
So everyone needs to go beg every single satellite provider to respect the well known existing radio quiet zones? I suspect it's more likely Starlink is ignoring all other regulators and regulations other than the FCC, hence why the US-based observatories are considered.
> This radio emission at lower frequencies from Starlink isn’t their downlink frequency, but instead unintentional electromagnetic radiation (UEMR), thought to be caused by the onboard electronics of the satellite. This UEMR is not currently regulated by the International Telecommunications Union (ITU), the organization responsible for managing and allocating the radio spectrum for various uses.
Feels like this is regulatory UB, and therefore allowed.
There are several related things I find odd about Starlink, with the ongoing defense of the impact it has on scientific research being one of them.
Having used it it is genuinely impressive, but it will inevitably lead to everyone wanting their own independent LEO constellation for military purposes (communication and observation), which will then lead to a big interest in anti-satellite weapons since these will become major targets in a hot war.
The end result here is going to be huge quantities of space junk and investment in defense over-the-horizon ground radios (again) which to some degree is already happening.
there is no evidence that there will be a hot war, that it will involve destroying satellites, or the process of destroying the satellite would result in space junk that didn't naturally deorbit within a few years
if we have a hot war with a country capable of launch rockets into space to destroy satellites, then we're super fucked anyway, because that's also a nuclear country. satellites would be the last of my concerns, i would be digging a bunker in my backyard
Big % of mega constellations will be be >500km where deorbit is decades to centuries. Unless regulatory changes, VLEO will be minority because orbit slots is limited.
Care to share where you're pulling that information?
1. The amount of "orbit slots" is vast. There is plenty of room.
2. I'm unaware of any mega constellations planned >500km. Latency would be worse and doesn't make sense for an aspiring Starlink competitor to do that.
1. UN/ITU regulates orbit slots/shells (really frequency assignments that effectively limits orbit slots), high decay V/LEO, as in ~500km was basically exhausted by starlink. Big reason PRC announced multiple 10-20k mega constellations a few years ago (without reusable for to put-up payload) was to sign up for next closes shell which is 500+. At those distances orbit decay is decades/centuries. So regulatorily, the fast decay orbit slots are legally mostly gone.
2. All mega constellations including starlink has layers from 500-1500km. Every 100km is like 0.3ms latency but trade off is cheaper station (longer life time) keeping and wider coverage per satellite, but cost more to get there.
Related to 1&2 is this is byproduct of UN/ITU regulations... they can open up more <500km slots, increase congestion, confliction and chance of recoverable Kessler... but that would mean SpaceX (read US military) would... have to share strategic orbits with PRC and whoever comes next.
E: extrapolate to future of cheap space launch, if multiple blocs or even countries want their own mega constellations, and no changes to regulations, then they would have to start occupying higher orbit shells (assuming they follow ITU). Also geometrically, the shell lowest/closest to earth has the least volume / capacity.
Starlink competitors don't have SpaceX rockets and will tend towards different kinds of solutions to compensate. It is indeed significantly worse (signal strength, beam overlap) to go up to higher LEO altitudes, but that's a tradeoff you might make if you're inconfident about your orbital launchers and want to minimize risk there. You would need fewer satellites for initial coverage—fewer launches.
China's Thousand Sails (Qianfan) is secretive but possibly targets 800 km shells; I'll just quote Mike Wall and Jonathan McDowell,
> "That number is growing all the time; SpaceX has already launched more than 50 dedicated Starlink missions this year, with many more on the docket. Elon Musk's company already has permission to deploy 12,000 Starlink spacecraft in LEO, and it has applied for approval for another 30,000 on top of that."
> "Qianfan won't be quite that big, but it's in the ballpark."
> ""The satellites are similar to the V1 Starlinks, with flat-panel morphology and a mass of 300 kg [660 pounds] each. This 'G60' constellation is planned to eventually have 14,000 satellites," astrophysicist and satellite tracker Jonathan McDowell, of the Harvard-Smithsonian Center for Astrophysics, posted on X shortly after today's Qianfan launch."
> "The Qianfan satellites will apparently orbit at an altitude of about 500 miles (800 kilometers), he added in another post. That's higher than the Starlink constellation, which orbits at about 340 miles (550 km)."
>which will then lead to a big interest in anti-satellite weapons since these will become major targets in a hot war
If anything, the other way around. Were Starlink a traditional satellite constellation, with a few in geosynchronous orbit, they would be very appealing targets. But there are thousands, and soon tens of thousands, of Starlink satellites, which makes any sort of weapon against them other than maybe a laser impractical.
>The end result here is going to be huge quantities of space junk
... the Starlink portion of which naturally falls back to earth within five years.
I have often wondered if a a very small Ion thruster, used intermittently, gravitationally stabilised, could be used to offset the variable atmospheric drag caused by inflation/deflation of the tenuous upper atmosphere to extend satellite life. It would add a little weight at launch but could extend orbital life by many years. It would need fractions of a gram of thrust, run off the current solar electricity budget, and could easily make them endure for 10+ years. When the satellite had failed or aged out, it could be used for improved de-orbiting at end of life.
I also suspect that a mobile stream at a lower frequency could be added that would provide intermittent stream down loads of news directly to the Russian people via recently tested cell phone comms ability
> I have often wondered if a a very small Ion thruster, used intermittently, gravitationally stabilised, could be used to offset the variable atmospheric drag caused by inflation/deflation of the tenuous upper atmosphere to extend satellite life.
Not all sats in general have thrusters. There's many types of satellites, especially smaller ones, that use magnetorquers, and somtimes reaction wheels as well, to maintain orientation but have no propulsion.
There's also satellites with no active attitude control at all and use passive means to maintain a somewhat static orientation. That can permanent magnets causing a tumbling linked to Earth's magnetic field, passive aerodynamic stabilization, or using Earth's gravity gradient to align the satellite.
I think I have a different idea of "valuable". Rural communities need connectivity for sure - but we also need reliable radio astronomy for a whole host of reasons - space weather forcasting, terrestrial weather forecasting, scientific advancement.... without radio astronomy, there wouldn't even be satellites to put cat videos on!
Launching tens of thousands of satellites is better than municipal internet, which would serve the same purpose, be cheaper, and not interfere with critical scientific research? This solution is better only for the private internet oligopolies. I would say astronomical research is orders of magnitude more important than that.
If Starlink / SpaceX interferes ground based scientific observations they should be required to pay in kind and launch orbital observatories as compensation.
i'm positive spacex would be thrilled to launch something like a JWST and get to write off the $150-$220 million launch "value", which is what the Ariane 5 ECA costs. since it'd only cost them as low as $10 million with reuse. the tax write-off would benefit them immensely
Google says their 8,094 satellites use phased arrays. I wonder what would happen if you directed a few hundred of these phased arrays at a single target?
Putting too much stock in coherence. Sunlight is not coherent, but throw enough of it at a target, and things happen. Little moments of constructive interference are enough for an effect.
From your article:
> Note that the thinned array curse applies only to mutually coherent sources. If the transmitting sources are not mutually coherent, the size of the ground spot does not depend on the relationship of the individual sources to one another, but is simply the sum of the individual spots from each source.
Sun, all the points are about the same distance from you. They all contribute about equally. Well, all the ones over the horizon, but anyway.
Satellites, well, first, most are below the horizon at any given moment, and unlike with the sun this doesn't just halve the number of sources visible. But let's pretend the earth is transparent. The satellite closest to you is four times brighter than the ones twice as far away as the closest, and the distant ones are about (525km/(12742km + 570km))^2 = 0.00156 times the brightness of the closest.
The point I'm making with the thinned-array curse in response to a comment about their phased array antenna is that the scenario is a thinned array, and that phased arrays, while useful, don't solve everything.
From the shell theorem, the sum of the effect of of all of them at any point inside their orbital shells can be approximated as* a constant value everywhere equal to the effect if you put them all in the middle and measure at the shell radius, so radius = 12742km/2 + 540km = 6911 km, so 8000 * (540km)^2 / (6911km)^2 ~= 48.8 times the brightness of a single satellite. So even all of them is not much.
* Approximation will diverge noticeably roughly when you're closer to the shell than the separation of sources in the shell
I think most people assume the individual satellites aren't synchronized well enough to produce a mutually coherent signal so the power from each of them will just be normally superimposed.
IE they're thinking of the individual phased arrays as just highly directional antennas for the satellites. The idea that they could be coherent actually means there could be more power than we might expect.
With any kind of feedback from the ground (to compensate for atmospheric effects), I think these could easily be coherent. One just needs timing accurate to 100 picoseconds within one 20 millisecond round trip - which is 5 ppb and the cheapest atomic clocks can do that.
Even so, my guess is you aren't going to be frying an egg 500 km away even with the whole starlink constellation at full power!
The mind likes to wander to "what if death ray?" but the real, boring answer is probably that money === yams, and those who have the yams have the power. The array provides paying customers who bolster the war chest, and maybe down the road the satellite array could be used form something, but if they all burn out or otherwise become junk over time, at least the paying customers have galvanized the bank account.
Then with the bank account, you can do whatever else needs to be done at a later date
I was thinking more along the lines of Havana Syndrome. The brain is an electro-chemical system, so this is as much a biology question as it is a physics one. Direct enough wattage at it for long enough, who knows what the effects will be? Not cooking, but signal interference.
Well, you could use it a kind of active, reverse GPS, for one. Track anything with the faintest (within reason, we have a lot of noise in the direction of earth) em signature.
When an individual transmits on a band they shouldn't the FCC issues a fine. When a company transmits on a band they shouldn't the FCC gives them the band.
https://www.pcmag.com/news/despite-spacex-protests-fcc-clear...
Comment period ended in July.
https://www.fcc.gov/ecfs/search/search-filings/results?q=(pr...
> "When a company transmits on a band they shouldn't"
The source article is quite clear there's no regulatory violations here.
> "Although this IEMR abides by ITU-R guidelines, these intensities are large compared to the strongest astronomical radio sources in the sky and will therefore have the potential to disrupt astronomical observations at SKA-Low frequencies;"
> "The detected IEMR and UEMR are outside of the frequency bands protected for radio astronomy, but are at frequencies of great interest for key experiments for the SKA-Low facility, and at frequencies where RQZ protections at the SKA-Low site are in place;"
The source states that the UEMR SpaceX causes in this spectrum is currently not regulated but interferes with astronomical observations.
The claim stands whether a regulation will be put in place which will require SpaceX to fix or switch off their (thousands) of satellites polluting the spectrum or the band will simply be handed to SpaceX.
"This UEMR is not currently regulated by the International Telecommunications Union (ITU), the organization responsible for managing and allocating the radio spectrum for various uses"
Lots of things interfere with astronomical observations - if someone builds a house, it'll interfere with their neighbors observing a star close to the horizon.
Especially since the observations appear to be outside the protected spectrum, the answer is "that's probably okay". There's balancing that needs to be done - does the safety benefit of a world in which nobody can be out of contact of emergency services, and the economic benefit of having reasonably high speed internet available everywhere, outweigh the loss of radio astronomy potential.
I think it probably does.
The long-term balancing is whether humanity can take over Earth's orbit and build out advanced technology there, or not. I think in the long run, radio astronomy is the one that will have to bend. If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space, there's no reasonable way to adapt to that—it's unreasonable to ask an entire planet to turn into a radio-quiet zone over its entire orbital shell. Intentional broadcasts are one thing—that's what spectrum licensing regulations are for. Minor EMI is a bridge too far.
Further context: the signal strengths they're talking about are equivalents of isotropic emitters in the *milliwatt* power range, detectable down to the microwatts—detectable at ranges of thousands of kilometers,
https://www.aanda.org/articles/aa/full_html/2023/10/aa47654-... ("Detection of intended and unintended emissions from Starlink satellites in the SKA-Low frequency range, at the SKA-Low site, with an SKA-Low station analogue")
> "The flashes reach a maximum intensity of approximately 10^6 Jy beam^−1 at ranges of ∼500 km (EIRP ∼ 30 mW) and a minimum intensity of approximately 2000 Jy beam^−1 at ranges of ∼2000 km (EIRP ∼ 1 mW)"
Further context: part of the EMI isn't a fixable circuit design issue—it's (I understand) EMI from normal operation of ion thrusters,
> "The authors have been in communication with SpaceX (who owns, builds, and operates the Starlink constellation), who explains that this radiation is likely due to the satellites’ propulsion or avionics system and is likely over 50–200 MHz (SpaceX 2023, priv. comm.) The propulsion system is actively engaged during the time this train is detected. This radiation is therefore in the class of UEMR."
> If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space [...]
Well, that's what is required to receive a weak signal from beyond that circuit board, from outer space.
> there's no reasonable way to adapt to that
You'd be surprised what becomes reasonable and possible once a requirement is set.
> it's unreasonable to ask an entire planet to turn into a radio-quiet zone.
Noone is asking that.
It's reasonable to require radio interference of a device to stay within defined boundaries. This is the case in all other industries as well, why shouldn't it suddenly apply for a fleet of satellites which blast radio signals from outer space to earth?
> "This is the case in all other industries as well,"
No; it really isn't. There's no industry on the planet where "must accept" regulations are set by the world's most sensitive physics experiments.
Do we set acoustic noise regulations by what a LIGO interferometer can measure? Of course not. We'd have to outlaw the mechanical engine were it so. Regress to a medieval society of horse people (very small horses with noise-absorbing horseshoes).
Do we regulate nuclear power by what astrophysical neutrino detectors perceive? Also, no. Even though they see fission reactors on the other side of the planet, and it is noise to them.
The prior art is we that set noise regulations by what interferes with actual humans in their actual day-to-day functioning; and we set RF regulations by what interferes with the functioning of other circuits useful to humans. Not exotic physics experiments. This is a new thing to ask; and it is bold.
> There's no industry on the planet where "must accept" regulations are set by the world's most sensitive physics experiments.
The criteria is not industry vs. "world's most sensitive physics experiments", it's industry vs. "agreed activity for public/societal benefit". And there are many examples for it.
We regulate light/noise and other pollution in consideration of wildlife and plants, we regulate nuclear waste disposal considering our responsibilities to the greater public good.
We could also not regulate anything with regards to wildlife and plants, there is no immediate economic benefit to preserve all variants of rhinos, tigers, reptiles etc., we could kill all plants except the most resilient one, it's much more economic to maintain them in long-term then.
We could also globally agree to dispose all nuclear waste in one place on earth and just never go there again.
Actually we could disband entities like the EPA, because we can figure out solutions to each environmental impact on-demand if there's enough incentive for it.
But we don't, because there is (or used to be) consensus that there are also goals beyond short-term economic growth. Areas of interest for greater society, for mankind if you will.
> You'd be surprised what becomes reasonable and possible once a requirement is set.
In that case, I'm not sure why you're concerned. Let's flip this around: set up our regulations to loosen our EMI radiation restrictions & facilitate our satellites and space exploration. According to your logic, that should be perfectly reasonable to astronomers, if that's what the regulations say, and it should be possible for them to adapt to that.
If that's not what you meant, then astronomy needs to make some concessions.
Sure, that's also a solution. The public then needs to provide more taxpayer funding to perform such research in orbit of earth. Whatever is preferable in the larger picture of public/corporate interest...
That’s a very different proposal- unless you’re intending to amend your previous statement to:
“You'd be surprised what becomes reasonable and possible once a requirement is set [and additional funding is allocated to overcome the negative consequences of said requirement]”
No need to amend, it's the same, the required funding is a factor to determine how reasonable an investment is. For both parties.
It is then up to the taxpayer to define whether the path of performing astronomy research in orbit of earth to preserve a for-profit business-model is more reasonable than defining regulation which allows such research to be performed on earth for a fraction of the cost (but may require for-profit companies to further invest in R&D to comply or re-evaluate their business model).
It's that simple. Astronomy won't be able to provide immediate ROI or a sales-plan of increased revenue to offset the cost-increase when researching in orbit. So if that's the only criteria, then such research is a futile activity and will be stopped.
Even this assumes the rest of the world agrees to what is essentially a US centric thing.
Yeah, but hear me out: What is "US-centric" here?
Astronomy research?, Radio spectrum?, LOE?, Starlink operations?
All of this is global. In the end it'll be about geopolitics, although it should be a field that urgently requires global governance and consensus.
Next time it could be interference between Starlink vs. a Chinese for-profit. It would be good if there's a commonly agreed way of handling such matters in place...
If astronomy is not able to cope with additional regulation without additional funding, then for-profit companies should not be expected to do so either. It's that simple.
> Astronomy won't be able to provide immediate ROI or a sales-plan of increased revenue to offset the cost-increase when researching in orbit.
That's too bad. I was under the impression that "You'd be surprised what becomes reasonable and possible once a requirement is set."
> If astronomy is not able to cope with additional regulation without additional funding, then for-profit companies should not be expected to do so either. It's that simple
So your belief is that for-profit companies should not be required to comply to regulation put in place after they start business in any field.
And for-profit companies who later join to compete with them? They should, because it's not "additional"? Or also not, to ensure a competitive market?
So basically no regulation of any kind shall happen, because companies should not be expected to cope with new regulation if it incurs additional effort for them.
Congrats.
> So your belief is that for-profit companies should not be required to comply to regulation put in place after they start business in any field.
That is not what they said. That's an extremely bad-faith statement that's not even a "misinterpretation", because that implies that there is a valid interpretation, and there isn't - you just made up something completely different and claimed that they said it.
You're really not helping your argument here if you have to resort to lying about other peoples' words in order to try to defend your positions.
> So your belief is that for-profit companies should not be required to comply to regulation put in place after they start business in any field.
Interesting that was your takeaway, when all I actually said was "no double standards pls".
(i.e., hold astronomy and for-profits to the same standard, insofar that they have to just 'deal with it' when new regulation shows up - or not.)
Humanity doesn't own SpaceX. If humanity would have a vote on this I'd be happy to agree with you but it is just one US corporation that does this and they don't get to decide for all of us. If they just did their thing above the USA that would be another matter entirely but that's not how this works, as you well know. So you slip in the 'for the greater good' argument that does not necessarily hold and besides which isn't up to SpaceX to decide, especially not unilaterally.
> "but it is just one US corporation that does this and they don't get to decide for all of us"
I don't understand your comment on so many levels. The ITU treaties do exist, and they do protect observational astronomy bands, and everything here is *in compliance with* extant ITU regs. As I quoted above. I can turn your words on your head: who are astronomers to make arbitrary choices for rest of the human species? Or, who are HN to? People do want their gadgets to work. They value that more highly than many things, things more important than mere astronomy experiments—more highly than human rights, for example (to contemplate all the slave labor in the modern electronics supply chains).
On another level: you say it's just one one company, but that company is obviously just an early-adopter, leading-edge of a great horde of space companies going in for the gold rush. There will be many others, and then there will be the Chinese military, and—do you think there will be more favorable outcomes negotiating with the PLA, filing complaints to the PLA over the RFI of their prized military assets? Yeah; no. In 5-10 years the landscape will certainly be utterly unrecognizable, and it will not be a SpaceX hegemony any longer. You will be opposed to a hundred adversaries of many nations—not just that one.
And following after that, there will be humans and human tourists going up, pretty soon I'd bet; by the thousands; and they'll be bringing their electronics gadgets up to visit, and later inhabit, Earth orbit. Have you internalized the numbers we're discussing here? This telescope array can detect the equivalent of a short-range wireless Bluetooth gadget at 2,000 kilometers range—and they're complaining about it, they want that banned. (Literally—if it weren't for the earth in between us, my wireless mouse right here could be radiating greater signal power through your body, dear reader, no matter where you are right now on the planet, than these satellites flashes we're discussing here. Click, click.) No way is that compatible with a future of humans inhabiting space. The space RF environment is, incomprehensibly pristine as it stands... but that won't last, can't last, there's no way humanity moving to the stars will preserve that pristine silence, you might us well give up right away. Fighting it is futile, foolish, misguided, and more than a little misanthropic.
> If your receiver is so sensitive it's intolerant of stray EMI from a circuit board in outer space, there's no reasonable way to adapt to that
They also mentioned detecting narrowband transmissions from a commercial FM station, 300km from the radio observatory that reflected off the satellite.
Which, like, cool that they can detect that, but you completely lost me if want to ban all metallic objects in earth orbit.
That was the original type of communication satellite—the passive metal balloon,
https://en.wikipedia.org/wiki/Project_Echo ("Project Echo" (1960-69))
(Here's a historic irony: the field of radio astronomy was founded by people doing this stuff. The cosmic microwave background was discovered, by accident, with an RF horn built for this satellite relay experiment).
(Here's another weird one:)
https://en.wikipedia.org/wiki/Project_West_Ford ("Project West Ford" (1961-63)) ("The goal of the project was to place a ring of 480,000,000 copper dipole antennas in orbit to facilitate global radio communication")
Just send up a satellite that uses solar power to spew out sticky dust to cover everything metallic. The dust would be fairly efficient, as it would continue to orbit and stick to things over time.
Yes, this could cause problems, like loss of GPS, weather prediction and other scientific equipment, and enemies wouldn’t be able to keep an eye on each other as easily, leading to wars. But, maybe light pollution would be less annoying.
Progress is always the argument for pollution.
> There's balancing that needs to be done - does the safety benefit of a world in which nobody can be out of contact of emergency services, and the economic benefit of having reasonably high speed internet available everywhere, outweigh the loss of radio astronomy potential.
If this balancing argument is merely based on short-term economics, then of course the corporation always wins. Every commons becomes a tragedy in that world.
There are existing regulated bands for astronomy, which already shows the regulatory bodies don't just consider short term gains. The person you quoted weighs it against outweighing the loss of radio astronomy potential, saying much of the same. Who is this note about needing to compete with short term economic gains responding to?
Exactly, thank you!
There is also a huge safety benefit in killing all wild animals, and companies are even happy to build taxable businesses for that if allowed.
This needs to be evaluated and balanced against the economic benefit of having wild animals roam the planet free of charge...
/s
Well, sure, but "regulatory bodies update spectrum regulations for the common good" is a lot less charged a claim. It was the other specifics (breaking current regulation, treatment based on whether you are an individual or a company) that were contentious, not the resulting assignment itself, and at least half of that was clearly false.
Within the system the FCC is (putatively) operating under, they cannot fine someone for something they have no regulatory jurisdiction over. Congress could fix that pretty quickly if they wanted to, of course.
How is the whole Musk/Trump love affair going today?
The FCC doesn't enforce very strongly, mudduck and others like him have been killing CB channel 6 (and sometimes 19) for like 2 decades and nothing has been done nor will be done.
They obviously haven't encountered an angry retired man with a ham radio license, transceiver, and nothing but time on his hands.
They'd be begging for the FCC after that.
That's about AST Spacemobile, not SpaceX.
Which is exactly why I shared it. There is a clear pattern of corporate interference on public bands and a pattern of FCC enforcement being applied to individual interferers.
Wise of them to launch FM1 on an Indian rocket, then.
If they want to serve the U.S. market, which they do, they still have to deal with the FCC and comply with U.S. regulations, regardless of the launching country.
The wisdom was not launching a satellite on their competitor's rocket.
Mitigation is going to be the name of the game. Whether they like it or not, low earth orbit (LEO) is becoming a very busy place and it's not just SpaceX launching lots of little satellites there. The Chinese are very busy launching their own satellites into LEO. And there are other companies and countries doing or considering the same. Spacex and Star link get most of the attention; but the Chinese are doing a decent job to keep up with them in number of launches. And there are a growing number of companies with LEO launch capability.
Mitigation might have to involve some sacrifices. I don't see how policy is going to be able to mitigate much here. And of course the Chinese are under no obligation to listen to US policy makers. They might have their own debates domestically around this topic and they might be reasonable about the topic internationally even. But building international consensus; or even enforcing what little there is on that front could be challenging.
A more practical approach might be accepting that earth based observations are inevitably going to suffer a bit as the number of satellites grows from thousands to tens of thousands and eventually well beyond that. Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware. That's already happening of course. And otherwise, astronomy is very interesting and cool but mostly it concerns observations about things that are really really far away and not directly relevant to a lot of things on earth. Unless of course the thing under observation is on a collision course with us.
> Luckily we now are able to launch stuff into orbit a lot cheaper.
“We” as in the select few countries that have the launch capability and the space tech.
Again a public good is being commoditized and being sold to the highest bidder.
> a public good is being commoditized
Just like the inclosure movement, right?
https://en.wikipedia.org/wiki/Inclosure_act
With privatization, the public is paid something. Whereas StarLink's use of LEO is a taking. They're denying others open access usage. Without any possibility or threat of consequences.
"Use" is such an inadequate term, but I couldn't think of another. Commandeering?
Wow what a rabbit hole to get into.
The whole system of “lordship” is wild to me, I recommend watching Downton Abbey for a light intro into the topic :)
> “We” as in the select few countries that have the launch capability and the space tech.
There has never been more access to space-based imagery and other sensing. With multiple companies selling this stuff ever cheaper. Every news outlet can now afford to buy images. And that's because of cheap launches.
I thought that was the whole idea of spectrum auctions.
The RF spectrum is a public good in the US and there are requirements placed on the winners of those auctions to demonstrate it provides some public benefit. A company can't just buy spectrum and sit on it, for example. They must use start to use it in a certain timeframe.
The RF spectrum is a common good, not a public good. Public goods are non-excludable and non-rivalrous. The RF spectrum is non-excludable (anyone can transmit on any frequency, given the right equipment) but rivalrous (transmitting on one frequency prevents others from using that frequency).
Requiring the winner of a spectrum auction to use it is a way to prevent anti-competitive tactics (since the government is granting a monopoly to the winner). The goal is to incentivize productive use of limited resources, not necessarily to benefit everyone. In theory, the winner could use the spectrum for entirely internal purposes. Though in real world spectrum auctions, the government usually has stipulations such as requiring interoperability or using open standards. This reduces the value that the government captures, but likely increases the value that is created overall.
Before spectrum auctions, the government simply mandated what frequency bands were used for what, and by whom. Getting access usually meant lobbying and back room deals. Sometimes the FCC used lotteries, which caused speculators to enter lotteries and then license access (basically capturing revenue that would have gone to the government had the spectrum been auctioned). In practice, auctions are the worst form of spectrum allocation, except for all the others.
A global public good is being commoditized and being sold to the highest local bidder.
This seems circular… since the lack of a worldwide authority, that can decide the value of X public good is worth more than zero, is the issue in the first place.
A bit, it's 5 orders of magnitude over the required SNR?! From the article: "The authors estimate a lower limit of 93 Jy per beam in the frequency averaged images containing Starlink emission. Considering just 1 mJy of radio frequency interference could mess up an EoR power spectrum integration, this could severely affect SKA-Low EoR science."
> the required SNR
Require by who and on what authority?
My point here was not to contest that but make the point that the cat is out of the bag and that it is indeed impacting SKA-Low EoR science and the people involved with that have to deal with that.
Getting the cat a little bit back in the bag via policy and other means is maybe worth trying (good luck) but I don't give it a very high chance of success.
This makes me want to say "is nothing sacred?!" I get your point from a pragmatic: this is the world we live in, work with it, not against it.
I think you need to scope this approach when suggesting it though, since it's effectively "a policy has been broken by a company, but we can't undo it, so lets just accept it and let them get on with it" which doesn't seem like it'll lead to a better world.
I do agree with your point that the people who suffer from the policy breach have to be pragmatic in their handling. But ultimately, let's not let pragmatism and stoicism lead to businesses spectacularly breaking policies in hopes of being told "well the cats out the bag now, the victims can deal with it, you might has well continue".
> I do agree with your point that the people who suffer from the policy breach have to be pragmatic in their handling. But ultimately, let's not let pragmatism and stoicism lead to businesses spectacularly breaking policies in hopes of being told "well the cats out the bag now, the victims can deal with it, you might has well continue".
I fully agree, and that's IMO the core-issue here: This strong-arm approach of just forcing the problem to be solved in your favor by scaling as fast as possible and then pleading how uneconomic it would be for you to change course, insisting that the other side should be pragmatic about this.
I don't remember this was a working strategy in the past (imagine a car-company just accelerating sales of a faulty car to scale THEIR issue and avoid having to do a recall), but nowadays it could even be turned into a geopolitical topic...
I instinctively want to agree with you here and bemoan the state and directions of the world. But if I really think about it, it's been happening my entire life. I'm mid 30's now. I assume someone older than me would have had the same experience of it happening their entire life.
You're right though, it's crappy and merits a lot of geopolitical reflection. But I suspect it goes back millenia and is a manifestation of basic evolutionary biology with the business world, rather than anything that can be solved/fixed.
And we've gone full circle about the balance of working for/against humanity in the name of progress.
The EPA is only two decades older than you, and it enforced a bunch of brand new regulation on all the existing companies. There used to be a willingness to actually govern rather than cede everything to corporate interest.
I'm a bit older now, and while there has always been corporate meddling in public decision-making (which is unavoidable and also somewhat needed to help steer the boat a bit in some situations), the economic effort a company has to invest rectify wrongdoing mainly shaped the amount of spending for legal counseling and lobbying, but it didn't directly shape a ruling.
Today, environmental/privacy/safety laws are suddenly not that strict anymore, because now we naturally need to also take economic interests of the violating company into account.
So you might end up in a situation where an official body will officially rule that the harmed party may be right, but needs to be pragmatic about its needs just because of the increased inconvenience it would create for the opposing party if THEY would have to change their way.
In my experience, this was not the case 15 years ago.
It’s the definition of ‘too big to fail’, and it’s been a viable and effective strategy… for ever? Near as I can tell. He’ll, the Fed even got created because of the time the whole US economy cratered in the early 20th century and one man was the one whole bailed out the whole country.
'Too big to fail' is only said about companies that didn't collapse yet though.
But such companies also failed already. Enron, Arthur Andersen, WorldCom comes to mind. Even Blockbuster could be on that list...
The take away is they weren’t big enough to have enough leverage eh?
> The take away is they weren’t big enough to have enough leverage eh?
This reasoning has some parallels to "everything that can't be explained by science must be god". It stays valid even when proven wrong...
Eh, if they died and everything didn’t actually break in a terrible unsolvable way, then….
It’s essentially a form of market extortion though, so perception of ‘survivable’ matters as much as actually survivable eh?
Given that the offending entity is owned by the world's richest man certainly their 'pleading how uneconomic it would be for you to change course' should be dismissed instantly without a second thought.
> the cat is out of the bag
Someone, if we stretch that metaphor, intentionally opened the bag for profit. We can and should hold them accountable.
> the people involved with that have to deal with that
Yep, and they should hold the people who caused this accountable.
> is maybe worth trying (good luck) but I don't give it a very high chance of success
You may be correct that it has a low chance of success. However, people who think like you are exactly the cause. People who value Musk's net worth more than science, people who fetishise "progress at all costs," regardless of whether or not the progress actually helps people or is what makes sense (municipal internet, folks!). Understanding physics is also critically important progress, but it doesn't make money next quarter so you don't care.
So you'll forgive me if I don't take your advice on the situation.
> But building international consensus; or even enforcing what little there is on that front could be challenging.
No kidding! If something is worthwhile, people should and sometimes do go to the trouble!
Just roll over is not good advice here!
> "The Chinese are very busy launching their own satellites into LEO."
The Chinese (correctly) view these satellite constellations as a key military capability, and have gone all-in on creating their own version. (I mean, I don't see how that's even debatable at this point—having seen the influence of Starlink in Ukraine. Future conflicts will only amplify the gap between the haves and have-nots).
They haven't yet launched a large number (~120); they don't now have the launch volume for large-scale satellite constellations. Their race is to first catch up in launch capability. They have dozen private startups—heavily subsidized and favored by the state—in the race to build a viable, reusable launcher comparable to Falcon 9, that they would then use to launch Starlink-like constellations at the same cadence.
Some starting points:
https://www.wsj.com/world/china/chinas-own-elon-musks-are-ra... ( https://archive.is/Ukmoa ) ("China’s Own Elon Musks Are Racing to Catch Up to SpaceX / Private sector takes bigger role in building reusable rockets, advancing Beijing’s goal of independence from Western technology")
https://www.nytimes.com/interactive/2025/07/23/world/asia/st... ("This Was Supposed to Be the Year China Started Catching Up With SpaceX / It’s looking unlikely. Here’s why")
> Including astronomy related hardware
Can't feasibly do VLBI or other radio astronomy at useful scale in space even if launches were free. Look up the scale of SKA or the EHT.
I'm not clear why not. The scale of the completed SKA-low (512*256 = 131,072 antennas, 1.8 meter lengths) is the same as that of Starlink itself. It's even less mass; the antenna parts alone, they are wire dipoles, they say they only weigh 1.6 kg each.
https://arxiv.org/abs/2301.06708
Why can't humanity launch 2^17 small antennas into deep space, as a free-floating constellation?
It's just nowhere near feasible. Each element would need power, orientation, precise positioning and a data link to the processing stations. For SKA low the raw data rate from all antennas is something like 2 Pb/s. Which is more than all of Starlink combined. Which is massively stepped down to 7 Tb/s by the central processor, a supercomputer with purpose built signal processing hardware. Then the next stage takes it to 100 Gb/s. You would likely have to transmit the data via radio links, which would defeat the purpose of going to space. When a radio telescope is built in space it will likely be on the Moon (or in orbit), designed for lower frequencies and much less ambitious than SKA low.
I still don't understand the case; sorry. Actually, we're not working with the same set of facts seems to the main thing.
> "would likely have to transmit the data via radio links"
No; you'd use free-space optical communication, which doesn't interfere at all, and which Starlink has pioneered. They have working laser links at 200 Gbps, per link,
https://news.ycombinator.com/item?id=39200323 ("Starlink's laser system is beaming 42 petabytes of data per day (pcmag.com)")
The optical bandwidths potentially accessible, in vacuum, are much wider than that of microwave links to/from Earth.
> "a supercomputer with purpose built signal processing hardware"
I don't see why couldn't put that in space, today. That SKA signal processing system you're talking about amounts to 100 petaflops, drawing 2 MW of power. That's far less power than Starlink already has in orbit right now (somewhere in the 10's of megawatts). It's even within a factor-of-10 of raw compute—the figures I found say each V2 Starlink has 1.2 TFlops of local processing.
I don't understand why it'd be impractical to put an equivalent signal-processing system in orbit. At any rate, there's YC startups getting funded for space-compute proposals more ambitious than that,
https://news.ycombinator.com/item?id=43977188 ("Starcloud (ycombinator.com)")
Laser links would make everything more complicated and expensive. Radio antennas can share the same hardware to link with many terminals, not so with laser systems. They are point to point, so you need many more. They also require precise pointing, you can forget passive spacecraft. The number of 42 PB per day is about three orders of magnitude lower than the data rates required by SKA Low.
>I don't see why couldn't put that in space, today.
Because the electronics are not built for space. Space rated electronics is about a decade behind their ground based siblings. Radiation is one of the most problematic, degrading electronics and disrupting digital memory. You also need petabytes of temp storage. Which, again, doesn't exist. For reference, JWST carries a 70 GB solid state recorder, I think Roman has about 1 TB. Then there is all the cooling, which is difficult in space. Saying there are some start-up considering computing is not the same as it being possible to order a system like this today.
The question is not could it theoretically be done, but can it be done on even the sorts of budget of a space science mission. And the answer to that is no. SKA pushes computing and technology to the limit on the Earth, where these things are much more advanced.
Geosynchronous satellites could give us even longer baselines couldn't they? Or even at l4 and l5. They don't get shielded by the earth like l2, but the station keeping would be easier. That would be a massive baseline
Baselines are one thing, you need a huge collecting area to get useful sensitivity, which there is barely budget for to build on earth, let alone in space
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware.
Honestly once Starship is operational SpaceX should subsidize launches of non-commercial astronomy hardware. Could build some goodwill to offset the negatives.
You just made me realize that the younger generation is never going to be able to reliably "wish upon a <shooting> star" ever again.
No , regulation. That’s what is necessary for cars, planes etc , otherwise the competition would lead to low emission cars . Plus the space debris creation , which is also unregulated , but threatening humanity - for profit
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware. That's already happening of course.
Seems more effective for astronomers to embrace it. Perhaps by getting SpaceX to add a few dozen hundred satellites kitted out for radio astronomy. Link them together and it could be amazing for radio astronomy!
How do the various LEO constellations mitigate band interference issues? Does the US/China have some agreement as to which bands their respective countries' companies will use?
> Spacex and Star link get most of the attention; but the Chinese are doing a decent job to keep up with them in number of launches.
Nobody anywhere is anywhere near SpaceX’s launch cadence, reusable or non.
Ah, the techbro defence. "We already started doing it, so I guess you're just going to have to let us".
> Whether they like it or not,
A swarm of LEO satellites because in the current political climate it's easier to massively pollute orbits and prevent astronomy than do municipal internet is not, in fact, a law of nature; nor is it inevitable.
> But building international consensus; or even enforcing what little there is on that front could be challenging.
Ah, a challenge! Let's all give up immediately; this could make some rich people a lot of money, after all!
> Luckily we now are able to launch stuff into orbit a lot cheaper. Including astronomy related hardware.
Would you like to pay for launching Vera C. Rubin (8.4m, nearly 20,000kg for just the camera and mirrors) into space? How about the TMT (30m, expected ~2.6 million kg)? Truly spoken like someone who knows nothing about astronomy.
> And otherwise, astronomy is very interesting and cool but mostly it concerns observations about things that are really really far away and not directly relevant to a lot of things on earth.
Apparently fundamental physics is not very relevant to us here on Earth! This is one of the most small-minded statements I've ever read.
We're fucked once they have the ability to launch payloads that are too big and/or beefy to fully burn up on reentry.
Why do we have to launch tens of thousands or even more satellites?
There is no royal "we" that "has to" do anything. There's just groups of people and countries making use of a shared resource, LEO.
Your underlying question as to why some of those are launching satellites is much easier. They are apparently quite useful for things like communication, providing internet, etc. And people are willing to pay for that kind of stuff. It's not more complicated than that.
This internet fad seems to be hanging around and bandwidth is probably linear in satellite count.
Why do we need radio telescopes. Satellite communications are infinitely more useful for people on earth than some research papers about things light-years away
> Why do we need radio telescopes.
Because they provide data that other types of telescopes do not. We have X-ray telescopes. We have infrared telescopes. We have optical telescopes. Also as a bonus, for ground based radio telescopes, we can use them 24/7 instead of waiting for nighttime.
Yes, but if it hadn't been for the efforts of visionary scientists at NASA trying to reach the stars, there would be no means of putting those satellites into orbit.
This is the but I don’t see the relevance. Is there an argument / position there or just an observation?
The point is basic science (e.g. radio astronomy) is, if not necessary, then highly desirable, because it can lead to unimaginable advancements in humanity (or in a country’s technological and military capabilities if that’s how you think).
Sure, and industry is also valuable and contributes to progress. I don’t think it’s useful to say one must always take priority over the other regardless of specifics.
I don’t think that’s useful either and nobody said that.
Ironically, those satellites would not be able to communicate effectively without the understanding of relativity that was obtained by looking at things light-years away.
Einstein developed relativity from mathematical reasoning. A major influence was the michaelson morley experiment, which was solely done on earth. Relativity was developed in the early 1900's and the first radio telescope was made in the 1930's. Also, orbital mechanics uses mostly Newtonian mechanics and the communication of satellites is radio waves which were understood way before einstein. There is no relativity involved. Literally everything you said is factually incorrect.
Satellites experience time dilation because of their orbital velocity and gravitational field being significantly different at their altitude. Without accounting for this, the clock drift would become unmanageable and Newtonian models are insufficient to correct for it.
You're right that the majority of Einstein's theories were ultimately thought experiments but getting the parameters correct involved a lot of measurements and experimenting, to get to where tech like GPS and StarLink can be accurate. We were also looking at far away stars for centuries before Einstein so that he could have the environment for his ideas to be discussed, which I was including in my phrasing "looking at things light-years away."
I wasn't saying it to start an argument, though. I wanted to counter the rather dismal view of "why do we need radio telescopes."
Einstein developed a theory that includes General relativity and special relativity. Experimental results confirms both of them, with special relativity being the easiest one to understand the consequences of. Without experimental confirmation, neither theory would be valuable.
Communication requires accurate timing. Time dilation occurs between Earth and satellites, a phenomenon that isn't part of Newton mechanics, so relativity is indeed involved.
"We" don't have to launch anything at all. SpaceX needs to launch enough satellites to satisfy customer demand for their constellation. In general the trend actually is that SpaceX is launching fewer but larger satellites (initially they were doing 60 satellites per launch, but they made them larger and now launch 24-28 satellites depending on the orbit inclination.
You should also ask why do we have to do this particular research? Both parties are impacting this particular band of the spectrum. One by excluding others and the other by radiating in those frequencies.
Excluding others only in a way that is not dissimilar to you locking your doors/windows to exclude others from freely entering your house.
Yes, some of the premiere radio observatories have radio transmission exclusion zones around them, but they are also typically away from that exclusion zone impacting as few as possible. Starlink on the other hand is not attempting to do anything of the sort. It would be interesting of Starlink could respect a geofence kind of idea so that they stop broadcasting when over certain areas, especially since they do this over geopolitically exclusion zones.
If you think the internet is a big deal, you haven't run into how happy the military is to have high bandwidth low-latency communications anywhere on the planet.
Starlink is nothing compared to the value Starshield provides, and the civilian product drives costs down.
With drone warfare being the next thing, the US probably can't afford to not have a company running a major LEO ISP.
As others have said, because it's a key military capability.
Humanity is what humanity is, not what we wish it'd be, so key military capabilities need to be developed or you get razed by the guy who did develop them. Doubly so now that we've rediscovered that culture is much more resilient than we'd thought, and that different people want Earth to look in different ways.
Do we all wish we'd stop ecological collapse instead? Yeah. But it's not going to happen so it's irrelevant.
Because the speed of light is slow and orbital mechanics can’t be changed.
To have internet everywhere you need to either accept bad latency (300-500ms round trip) or have closer satellites, which means they’re moving faster, which means you need more of them.
If we had a trusted powerful peacekeeper with a track record then we wouldn't need to. But now that masks are off everybody is busy launching dual purpose sats and whoever launches the least can literally get nuked from orbit if they don't do whatever the guy with more sats wants.
Then whoever has the most sats will say "that's it guys, LEO is full and you need our approval to launch more" and if someone raises a stink you guessed it, they can get nuked from orbit
There are no kinetic NOR nuclear orbital strike capabilities for anyone right now, nor is anyone really working on it either, because it just makes zero sense (primarily because suborbital launches achieve the exact same outcome for a tiny fraction of the cost).
Wouldn't having them already up give a lot less warning in a first strike situation? Also redundancy if all your subs, silos, and bomber bases got hit first by their satellites. It doesn't even have to be rational though, combinations of graft and brinkmanship would be enough. It seems really optimistic to think they haven't all already done this.
> Wouldn't having them already up give a lot less warning in a first strike situation?
Improved first strike capability is worthless íf it isn't crippling, and "devastating enough" first strike capability from orbit is completely unaffordable, and impossible to build up unobserved.
Being in orbit is a hindrance more than anything, really, because maintenance becomes ruinously expensive, everything is trivially observable for all your adversaries and you have to align the orbit with your target beforehand, too (which, again, everyone can observe).
> It doesn't even have to be rational though, combinations of graft and brinkmanship would be enough.
Enough for what? Threatening to nuke some satellites? Because anything else you can do easier, cheaper and on a larger scale from the ground. Why would you bother with nuclear warheads in space when you can just build/maintain like 10 ICBM silos for the same cost?
> Wouldn't having them already up give a lot less warning in a first strike situation?
From GEO, no. From LEO, still probably no.
There may be a bird positioned just right so a small deörbit burn pots Moscow quicker than an ICBM could. But the moment you start burning, you’re caught. (Same as an ICBM.) And unless you have a really obvious orbital configuration that bunches a bunch of birds in a way useful for practically nothing but such a strike, you only get one or two such “early” shots before a wall of ICBMs would have landed.
Nukes in space aren’t about nuking the ground from space. It’s about space area denial through EMP.
Here's a fun snippet from Wikipedia's anti-satellite weapon page: https://en.wikipedia.org/wiki/Anti-satellite_weapon#Soviet_U...
"Elements within the Soviet space industry convinced Leonid Brezhnev that the Shuttle was a single-orbit weapon that would be launched from Vandenberg Air Force Base, manoeuvre to avoid existing anti-ballistic missile sites, bomb Moscow in a first strike, and then land. Although the Soviet military was aware these claims were false, Brezhnev believed them and ordered a resumption of [satellite destroyer] testing along with a Shuttle of their own."
The exact claim might have been false, but at least i theory it could do this maneuver from orbit - e.g. during a regular space hab or satellite lunch mission it could dipp into the atmosphere, do a rapid oebit inclination chang using its wings, then boost back to orbit using the OMS. Next thing it would deliver the "totally science experiments" on the way to their targets once comming over the horizon. Maybe it could then even do the manuever again to either regain the old orbit parameters ir at least reach a more surivable random other one.
> at least i theory it could do this maneuver from orbit
Nukes from LEO aren't impossible. They're just impossible to do better than the current triad. Any breakthrough in propulsion that would make a plane change easier or less visible confers the same advantages to an ICBM. There is a narrow window in which orbital nuking can outperform, and that's almost entirely taken care of--and exceeded, in stealth--by SLBMs.
Nuking from orbit was not literal. The point of sats is intercepting. Sats allow you to nuke the other guy while intercepting his rockets. Same result...
> The point of sats is intercepting. Sats allow you to nuke the other guy while intercepting his rockets
Space-based missile defence is not what’s implied by weapons that are “already up” and thus “give a lot less warning in a first strike situation?”
> Wouldn't having them already up give a lot less warning in a first strike situation
No. Your missiles have further to fly from geostationary orbit than a missile silo on the ground, not to mention the additional complexity of designing your ICBM for reentry
You could have ballistic missile interceptors in orbit, standing by: https://en.m.wikipedia.org/wiki/Brilliant_Pebbles
It's a figure of speech, sats have been used many times to intercept missiles, for spy purposes etc
“nuked from orbit” is an ancient meme from Aliens (1986); it’s not meant to be taken literally.
https://www.urbandictionary.com/define.php?term=nuke+it+from...
I'm curious to see how this will play out.
I don't see big potential for the current US government to value scientific interests higher than the interests of SpaceX.
Wouldn't be surprised if SpaceX just continues to launch such satellites causing unintentional interference, to then claim in case of escalation how uneconomic it will be for them to correct this issue now and how the financial impact to SpaceX needs to be valued higher than scientific needs.
This LEO Direct-to-cellular strategy seems to play out similarly, with SpaceX launching massive amounts of satellites which are technically not capable to prevent interference on private spectrum while crossing country-borders, so ITU/FCC/CEPT now need to find a solution to deal with this situation.
> I don't see big potential for the current US government to value scientific interests higher than the interests of SpaceX.
Do not underestimate the motivating factor of spite in the current US administration.
Spite about what? Elon hasn't done a single thing to harm the administration. The bill he claimed to dislike passed easily, he stopped talking about Epstein as soon as it seemed like it might cause actual problems for the president, and in the past couple days he's expressed very vocal support for the Texas gerrymandering effort and domestic deployment of the military in DC. He continues to be the administration's most powerful and influential supporter in the world.
> Elon hasn't done a single thing to harm the administration
Literally reïgnited the Epstein drama.
They've made up since, with a plan to use the drama and outrage to disparage and prosecute political opponents of the President. Congress and Trump-appointed judges seem to be acting in support of that approach so far.
> They've made up since
That may be true. But it’s definitely a hot take.
Musk and Trump have agreed a detente. We have no signs of them helping each other. Where Musk has made up is with the GOP machine, particularly in the House. That looks less like alliance than positioning.
I consider stuff like this to be helping Trump: https://xcancel.com/elonmusk/status/1952836498971344926, https://xcancel.com/elonmusk/status/1954857646420369890, https://xcancel.com/elonmusk/status/1955036144909029873
That’s a detente. None of those tweets actually do anything.
> Wouldn't be surprised if SpaceX just continues to launch such satellites causing unintentional interference, to then claim in case of escalation how uneconomic it will be for them to correct this issue now and how the financial impact to SpaceX needs to be valued higher than scientific needs.
At least Starlink satellites need to be replaced every few years anyway due to their low orbit. That is a natural ceiling for economical questions - ITU et al take years anyway until anything is actually enforceable, so SpaceX has ample time to prepare should there be a relevant movement in ITU.
That's weird.
The company I'm working for has its own EMC chamber (maintaining that huge room fully calibrated and standardized is ultra expensive... just looking at these EMC test receivers that go up to 40GHz my me cry in $$$$) and we invested giant engineering effort into our products to be far below every radiation limit norm in the world.
Shouldn't satellite companies have even better stuff and more strict regulations or are these unintended effects maybe caused by the harsh environment?
They did. These are sub 1 Ghz bands and the issue is from the engines and (maybe power supply)
Most communications satellites (which is all Starlink really is) are heavily focused on their operating bands and any specific bands they are told not to interfere with so they can get launch approval. There's no benefit to doing anything extra. And not only do they have to be told which specific bands they can't interfere with, the government actually has to require delivery of test results or else that is the same as giving permission to interfere.
Most companies won't spend a penny, take a second of time, or add a gram to a satellite if it doesn't affect their mission or chance of approval. Especially not one as cost-optimized as SpaceX. They won't change a thing unless the US government forces them to do so, or if they think that a government order is imminent so they come to some voluntary agreement ahead of time to avoid what would probably be a more constraining official regulation in the future.
The actual issue is probably caused by switch-mode power supplies or some digital signal on the satellite that isn't fully shielded, possibly one that does digital control of a motor or thruster. It probably isn't the communication radios since they operate at a much higher frequency. You can fix the issue by adding filtering and/or shielding, but that takes extra components (meaning extra cost and weight) and requires testing (meaning time). Plus you have to identify the offending system, which means you have to start with testing and detective work. This interference was only detected on some Starlink satellites, so you have to do detective work to find out if it is a particular operating mode or generation of satellite that is offending, do testing to confirm it, and then work on a fix.
This is actually not correct for Starlink. They did a lot of work to lower their albedo based on astronomer complaints, even though there wasn't any government regulation in this area.
It might apply to some of the emerging Starlink competitors however, especially the Chinese ones and AST.
The albedo reduction they worked on is the exact reason why I wrote this, "...or if they think that a government order is imminent so they come to some voluntary agreement ahead of time."
SpaceX only "voluntarily" did that because the government was likely to put more stringent requirements on them if they ignored the complaints.
I’m certain that SpaceX does not care about regulations
I'm not sure why they're complaining when the SKA isn't even active yet. Once it's active Starlink will do just like they have for other radio telescopes, avoid transmitting while they're in the boresight and in general don't transmit toward the antenna. This is a well practiced interaction at this point with scientific agencies in multiple countries.
The only thing that they can't stop would be things like reflected unrelated ground communications off of the satellite, but that would be very weak.
> avoid transmitting while they're in the boresight and in general don't transmit toward the antenna
Not sure this will help against the mentioned unintentional electromagnetic radiation (UEMR) likely caused by the electronics of the satellites themselves.
"This radio emission at lower frequencies from Starlink isn’t their downlink frequency, but instead unintentional electromagnetic radiation (UEMR), thought to be caused by the onboard electronics of the satellite."
One interesting complication is that it seems the propulsion, the electromagnetic ion thrusters, are one of the sources of unintended emissions,
> "Communication with SpaceX engineers suggested the UEMR originated from the propulsion/avionics system of the satellites as they were orbit-raising at the time of detection."
That's quite a big deal actually, if the propulsion system is the major source of interference. Firstly the propulsion system's operation is infrequent (at least at individual satellite level, although if you've got a constellation as big as SpaceX's you'll have satellites doing orbital transfer somewhere a lot of the time). Secondly it isn't a critical part of SpaceX's tech, and other solutions exist for future Starlink generations which wouldn't compromise its service offering at all. Of course interference from a propulsion system is also less directional and tweakable...
They use a high efficiency low thrust hall effect engine - for those kinds of thrusters you might have to run it continuously, possibly continuously to ballance out the atmospheric drag at low altitude. For normal chemical thrusters you indeed use the for just a bit very occasionally (or else you run out of propellant very quickly).
Still I agree it is fixeable - they can tune the hall effect thruster on newer sats to not radiate in this band & avoid running the thrusters when in the field of view of that one radio telescope at the times it is operating.
They're not running thrusters continuously except during orbital transfer. Otherwise they'd run out of propellant pretty quickly even with a HET, and operating smallsats at 559km doesn't require that much orbital correction. They probably fire them far more often for conjunction avoidance than station keeping, but again that's a reported 300 total manoeuvres per day across 8k satellites, which gives them a bit of scope to time them for when they're unlikely to upset regulators
Interesting - yeah, that way they should have sufficient margin to plan the manuevers to avoid the radio telescopes. :)
Uh, given there's been radio telescopes there for longer than starlink has existed, I'm not sure why they haven't stopped broadcasting in that area then.
It's possible they haven't requested it yet. I've only heard SKA complaining loudly in the media while American radio telescopes have very obvious blackouts visible on SpaceX's map because they've requested them.
So everyone needs to go beg every single satellite provider to respect the well known existing radio quiet zones? I suspect it's more likely Starlink is ignoring all other regulators and regulations other than the FCC, hence why the US-based observatories are considered.
There's several blackout holes in Europe as well. Two in Germany, one in Spain and one in Sweden.
> This radio emission at lower frequencies from Starlink isn’t their downlink frequency, but instead unintentional electromagnetic radiation (UEMR), thought to be caused by the onboard electronics of the satellite. This UEMR is not currently regulated by the International Telecommunications Union (ITU), the organization responsible for managing and allocating the radio spectrum for various uses.
Feels like this is regulatory UB, and therefore allowed.
There are several related things I find odd about Starlink, with the ongoing defense of the impact it has on scientific research being one of them.
Having used it it is genuinely impressive, but it will inevitably lead to everyone wanting their own independent LEO constellation for military purposes (communication and observation), which will then lead to a big interest in anti-satellite weapons since these will become major targets in a hot war.
The end result here is going to be huge quantities of space junk and investment in defense over-the-horizon ground radios (again) which to some degree is already happening.
this is what we call a slippery slope fallacy
there is no evidence that there will be a hot war, that it will involve destroying satellites, or the process of destroying the satellite would result in space junk that didn't naturally deorbit within a few years
if we have a hot war with a country capable of launch rockets into space to destroy satellites, then we're super fucked anyway, because that's also a nuclear country. satellites would be the last of my concerns, i would be digging a bunker in my backyard
I agree. The sky is gonna be so full of sh*t in the future
It's impossible for VLEO constellations to create space junk.
They naturally fall out of orbit after a few years.
And no they can't be "blown into" GEO orbit.
Big % of mega constellations will be be >500km where deorbit is decades to centuries. Unless regulatory changes, VLEO will be minority because orbit slots is limited.
Care to share where you're pulling that information?
1. The amount of "orbit slots" is vast. There is plenty of room.
2. I'm unaware of any mega constellations planned >500km. Latency would be worse and doesn't make sense for an aspiring Starlink competitor to do that.
1. UN/ITU regulates orbit slots/shells (really frequency assignments that effectively limits orbit slots), high decay V/LEO, as in ~500km was basically exhausted by starlink. Big reason PRC announced multiple 10-20k mega constellations a few years ago (without reusable for to put-up payload) was to sign up for next closes shell which is 500+. At those distances orbit decay is decades/centuries. So regulatorily, the fast decay orbit slots are legally mostly gone.
2. All mega constellations including starlink has layers from 500-1500km. Every 100km is like 0.3ms latency but trade off is cheaper station (longer life time) keeping and wider coverage per satellite, but cost more to get there.
Related to 1&2 is this is byproduct of UN/ITU regulations... they can open up more <500km slots, increase congestion, confliction and chance of recoverable Kessler... but that would mean SpaceX (read US military) would... have to share strategic orbits with PRC and whoever comes next.
E: extrapolate to future of cheap space launch, if multiple blocs or even countries want their own mega constellations, and no changes to regulations, then they would have to start occupying higher orbit shells (assuming they follow ITU). Also geometrically, the shell lowest/closest to earth has the least volume / capacity.
Starlink competitors don't have SpaceX rockets and will tend towards different kinds of solutions to compensate. It is indeed significantly worse (signal strength, beam overlap) to go up to higher LEO altitudes, but that's a tradeoff you might make if you're inconfident about your orbital launchers and want to minimize risk there. You would need fewer satellites for initial coverage—fewer launches.
China's Thousand Sails (Qianfan) is secretive but possibly targets 800 km shells; I'll just quote Mike Wall and Jonathan McDowell,
> "That number is growing all the time; SpaceX has already launched more than 50 dedicated Starlink missions this year, with many more on the docket. Elon Musk's company already has permission to deploy 12,000 Starlink spacecraft in LEO, and it has applied for approval for another 30,000 on top of that."
> "Qianfan won't be quite that big, but it's in the ballpark."
> ""The satellites are similar to the V1 Starlinks, with flat-panel morphology and a mass of 300 kg [660 pounds] each. This 'G60' constellation is planned to eventually have 14,000 satellites," astrophysicist and satellite tracker Jonathan McDowell, of the Harvard-Smithsonian Center for Astrophysics, posted on X shortly after today's Qianfan launch."
> "The Qianfan satellites will apparently orbit at an altitude of about 500 miles (800 kilometers), he added in another post. That's higher than the Starlink constellation, which orbits at about 340 miles (550 km)."
https://www.space.com/china-first-launch-internet-satellite-...
Late update: and the other one, Guowang, goes up to 1,145 km—there was one launched a few hours ago.
https://en.wikipedia.org/wiki/Guowang
https://bsky.app/profile/planet4589.bsky.social/post/3lwdf3c...
>which will then lead to a big interest in anti-satellite weapons since these will become major targets in a hot war
If anything, the other way around. Were Starlink a traditional satellite constellation, with a few in geosynchronous orbit, they would be very appealing targets. But there are thousands, and soon tens of thousands, of Starlink satellites, which makes any sort of weapon against them other than maybe a laser impractical.
>The end result here is going to be huge quantities of space junk
... the Starlink portion of which naturally falls back to earth within five years.
If it's unintended emission this seems like something that can be reduced by refinement of the satellite design.
I have often wondered if a a very small Ion thruster, used intermittently, gravitationally stabilised, could be used to offset the variable atmospheric drag caused by inflation/deflation of the tenuous upper atmosphere to extend satellite life. It would add a little weight at launch but could extend orbital life by many years. It would need fractions of a gram of thrust, run off the current solar electricity budget, and could easily make them endure for 10+ years. When the satellite had failed or aged out, it could be used for improved de-orbiting at end of life. I also suspect that a mobile stream at a lower frequency could be added that would provide intermittent stream down loads of news directly to the Russian people via recently tested cell phone comms ability
> I have often wondered if a a very small Ion thruster, used intermittently, gravitationally stabilised, could be used to offset the variable atmospheric drag caused by inflation/deflation of the tenuous upper atmosphere to extend satellite life.
Isn't that exactly what Starlink is doing?
starlink sats have thrusters?
Yes.
https://www.reddit.com/r/SpaceXLounge/comments/11cnh0w/starl...
Yes, I see, dated 2018 using rarified air as ion source. Totally solves the reaction mass needs and the electricity is solar
All sats have thrusters.
Station-keeping must be active for very many reasons, and sats with broken thrusters fall down fairly quickly.
Not all sats in general have thrusters. There's many types of satellites, especially smaller ones, that use magnetorquers, and somtimes reaction wheels as well, to maintain orientation but have no propulsion.
There's also satellites with no active attitude control at all and use passive means to maintain a somewhat static orientation. That can permanent magnets causing a tumbling linked to Earth's magnetic field, passive aerodynamic stabilization, or using Earth's gravity gradient to align the satellite.
My bad. I meant all of these useful, long lived sats. I knew "all" would bite me in the ass, but it's a reasonable generalisation.
Sats without active control last what... Weeks in LEO?
ESA GOCE and JAXA SLATS did that. SLATS went as low as 167km(104mi). Neither was air breathing.
The function these satellites serve is 1000x more valuable than the cost of inconveniencing a few astronomers.
Rural communities are being enriched all over the world through high speed internet access.
I think I have a different idea of "valuable". Rural communities need connectivity for sure - but we also need reliable radio astronomy for a whole host of reasons - space weather forcasting, terrestrial weather forecasting, scientific advancement.... without radio astronomy, there wouldn't even be satellites to put cat videos on!
Huh? How does radio astronomy affect space or terrestrial weather forecasting?
https://public.nrao.edu/ask/can-radio-telescopes-be-used-in-...
Launching tens of thousands of satellites is better than municipal internet, which would serve the same purpose, be cheaper, and not interfere with critical scientific research? This solution is better only for the private internet oligopolies. I would say astronomical research is orders of magnitude more important than that.
These rudeboys better pick it up, pick it up!
If Starlink / SpaceX interferes ground based scientific observations they should be required to pay in kind and launch orbital observatories as compensation.
The other NRO telescope would be a nice start: https://en.wikipedia.org/wiki/2012_National_Reconnaissance_O...
i'm positive spacex would be thrilled to launch something like a JWST and get to write off the $150-$220 million launch "value", which is what the Ariane 5 ECA costs. since it'd only cost them as low as $10 million with reuse. the tax write-off would benefit them immensely
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Google says their 8,094 satellites use phased arrays. I wonder what would happen if you directed a few hundred of these phased arrays at a single target?
Less than you may expect: https://en.wikipedia.org/wiki/Thinned-array_curse
Not relevant. That's talking about if you just move the array elements, not if you add more.
However the answer is still that nothing will happen. The power level on the ground is extremely weak.
Putting too much stock in coherence. Sunlight is not coherent, but throw enough of it at a target, and things happen. Little moments of constructive interference are enough for an effect.
From your article:
> Note that the thinned array curse applies only to mutually coherent sources. If the transmitting sources are not mutually coherent, the size of the ground spot does not depend on the relationship of the individual sources to one another, but is simply the sum of the individual spots from each source.
Sun, all the points are about the same distance from you. They all contribute about equally. Well, all the ones over the horizon, but anyway.
Satellites, well, first, most are below the horizon at any given moment, and unlike with the sun this doesn't just halve the number of sources visible. But let's pretend the earth is transparent. The satellite closest to you is four times brighter than the ones twice as far away as the closest, and the distant ones are about (525km/(12742km + 570km))^2 = 0.00156 times the brightness of the closest.
The point I'm making with the thinned-array curse in response to a comment about their phased array antenna is that the scenario is a thinned array, and that phased arrays, while useful, don't solve everything.
From the shell theorem, the sum of the effect of of all of them at any point inside their orbital shells can be approximated as* a constant value everywhere equal to the effect if you put them all in the middle and measure at the shell radius, so radius = 12742km/2 + 540km = 6911 km, so 8000 * (540km)^2 / (6911km)^2 ~= 48.8 times the brightness of a single satellite. So even all of them is not much.
* Approximation will diverge noticeably roughly when you're closer to the shell than the separation of sources in the shell
I think most people assume the individual satellites aren't synchronized well enough to produce a mutually coherent signal so the power from each of them will just be normally superimposed.
IE they're thinking of the individual phased arrays as just highly directional antennas for the satellites. The idea that they could be coherent actually means there could be more power than we might expect.
With any kind of feedback from the ground (to compensate for atmospheric effects), I think these could easily be coherent. One just needs timing accurate to 100 picoseconds within one 20 millisecond round trip - which is 5 ppb and the cheapest atomic clocks can do that.
Even so, my guess is you aren't going to be frying an egg 500 km away even with the whole starlink constellation at full power!
Only a fraction of the satellites have a single point in view.
A fraction of 8,094 is still quite a few.
The mind likes to wander to "what if death ray?" but the real, boring answer is probably that money === yams, and those who have the yams have the power. The array provides paying customers who bolster the war chest, and maybe down the road the satellite array could be used form something, but if they all burn out or otherwise become junk over time, at least the paying customers have galvanized the bank account.
Then with the bank account, you can do whatever else needs to be done at a later date
I was thinking more along the lines of Havana Syndrome. The brain is an electro-chemical system, so this is as much a biology question as it is a physics one. Direct enough wattage at it for long enough, who knows what the effects will be? Not cooking, but signal interference.
Well, you could use it a kind of active, reverse GPS, for one. Track anything with the faintest (within reason, we have a lot of noise in the direction of earth) em signature.
Similarly, what if each satellite used a laser link, what if each laser was pointed to the same spot - could it act like a Death Star?
or maybe just a really nice lens
"You may fire, when ready."
I mean they can't - the Earth is in the way for most of them.