SpaceX punched a hole in the ionosphere
spaceweatherarchive.com
spaceweatherarchive.com
> Rocket engines spray water (H2O) and carbon dioxide (CO2) into the ionosphere, quenching local ionization by as much as 70%. A complicated series of charge exchange reactions between oxygen ions (O+) and molecules from the rocket exhaust produce photons at a wavelength of 6300 Å–the same color as red auroras.
> Once rare, ionospheric “punch holes” are increasingly common with record numbers of rocket launches led by SpaceX sending Starlink satellites to low-Earth orbit. Ham radio operators may notice them... These effects may be troublesome, but they are shortlived; re-ionization occurs as soon as the sun comes up again.
Doesn't sound too local to me.
California's area is about 500 thousand km^2, and the Earth's is about 500 million, which means the side facing the Sun is about 250 million, so we're talking about 0.2% of the area facing the sun.
Suppose the hole takes six hours to heal (the article makes it sound like it takes much less), and suppose there's a launch every month (since launches have in the past carried 600 satellites at once, that seems plausible, no?), and suppose the hole lets in twice as much of whatever radiation we would like the ionosphere to keep out. Then that's an increase of 0.2 * (1/4) * (1/30) %, which is less than 0.002% -- that is, an increase by a factor of less than 1.00002.
Not negligible, but if the satellites provide a substantial public good, then it seems worth the cost. I feel like due to StarLink's use in Russia-Ukraine war alone, it more than qualifies.
Doesn't sound small at all.
I guess so, they will have to deal with increased fame and awareness of the size of their state.
People in Oregon on the other hand will continue to be snubbed.
But on the other hand, you typically don't launch rockets there.
Earth's radius: 6,371 km Ionosphere: 60-300km
... If we use the inner edge of the ionosphere we get about 2% more surface area whereas the outer edge gives us 9.6%. Probably the right number to use is somewhere in between.
Couple nits: - frequency estimate should be more aggressive, should be looking for an upper bound on all numbers to quantify max potential impact. I would crank that up to once a day or more.
- a hole allowing twice as much sounds like a comolete guess. Could it be 100x, 10,000x? or perhaps less than 10%? Other comments make the ozone layer sound more important. The hole punching effects on that layer are unknown (to me and the article does not mention it). In effect, this could be a light show, or it could be a routine perforation of each layer of the atmosphere (more data needed)
- that extra radiation is not spread out across the area of the earth. Instead how many people and animals are present under that hole. Everyone underneath the hole presumably would get the full blast. Thus, it is simple, those people get twice the radiation, whatever that factor is, it is not averaged across the whole planet because it is a local effect. Thus, the area sizes only matter for determining how many people and animals receive extra exposure.
- starlink donated their services to Ukraine. That one act of donation does not make it a public good. Starlink is a for profit service, not a public good (some services can be quite good, but that is different from "a public good")
I think the right way to approach this is to consider the unshielded radiation flux over the hole and the time that the hole takes to close. This would give a good back of envelope upper bound of the increase in cancer risk. There’s probably other effects, but all I care about is harm to individuals.
Edit: It also somewhat changes the scatter/delay characteristics of GNSS, which may or may not cause a somewhat significant error of the GNSS fix (it probably should not, but it can).
https://spectrum.ieee.org/amp/wall-street-tries-shortwave-ra...
That's where the high-frequency traders should put their fibers ;)
Radio clocks are low frequency.
I’m guessing that when radio first came out frequencies were lower, though I don’t have any facts there.
“Shortwave radio” is another one that’s confusing term these days for the same reason.
Their mere existence makes a mockery of the idea of the stock market as a considered reflection of value of companies and explicitly makes it into a gambling den for dead-eyed people competing to have the fastest card counting systems under their suits. If a company is valuable now, it'll be valuable in 5 minutes.
> If a company is valuable now, it'll be valuable in 5 minutes.
That’s not necessarily true.
I think we are going to have very different views as to what the terms "value" and "everyone" mean
because HFT's provide no value at all to the everyday person on mainstreet just looking get by and maybe put 10% of their wages into the stock market for retirement.
if by everyone you mean "the top 1%" and by value you mean "make lots of money at the expense of mainstreet investors" then sure.
If you participate in the stock market at all, you indirectly benefit from HFTs lowering the bid/ask spread and therefore getting a better price. Now matter how insignificant, but the benefit is there.
Of course if we're dealing in millions, not thousands, then the benefit is more pronounced, but a couple of cents here or there still make a difference.
At the very worst HFT firms are a net neutral.
> "make lots of money at the expense of mainstreet investors"
Can you elaborate on this further? I don't see how HFTs make money at the expense of mainstreet investors. HFTs make money on the expense of inefficiencies, therefore making the markets more efficient.
If someone writes some software, or grows some food, or balances some accounts, or paints a wall, they are all being endlessly more productive than someone who buys on a low and sells on a high and pockets the difference all within 100ms.
Investment means support and confidence in a venture or resource. I think a lot of the financial industry's problems arise from the switch from "investment in business x because I like what they're doing and am confident they'll succeed" to the mantra of "investment in business x because I don't actually care about the company but the stock history tells me I can make a quick buck". Market stability is a thing of the past, no wonder we're constantly on the edge of a recession.
There's a benefit to liquidity to everyone, but I don't really see a liquidity benefit faster than a few _minutes_, much less faster than a few _ms_: end individual traders don't even get to trade that fast anyway, they're just artificially disadvantaged against the institutions.
That undoubtedly deserves its own article, which will unavoidably be confused with this one and be considered old news.
Hydrazine powered rockets have a much bigger effect (all those nitrogen oxides) and are still not a very big deal.
In contrast, a SpaceX launch generates around 300 tons of CO2 [2], totaling about 72,600 tons of CO2 for the 242 launches to date. We mustn't forget the wide-ranging benefits these launches provide, from improved weather forecasting and GPS services to crewed missions to the International Space Station.
If we subtract the CO2 emissions from SpaceX launches from the CO2 savings attributed to Tesla, we see a net savings of about 89,927,400 tons of CO2.
90,000,000 / 72,600 = 1,240x
The emissions from his remaining companies are comparably negligible. Furthermore, this calculation doesn't account for Tesla's influence on the automotive industry, propelling other manufacturers to accelerate their production of EVs. As Tesla's sales continue to rise and EVs become more accessible through Tesla's charging network, these benefits will be multiplied. Also, this doesn't factor in the positive environmental impact of Tesla's energy division, which likely offsets the emissions from all of his other companies on its own.
[1] https://www.iea.org/data-and-statistics/charts/comparative-l...
[2] https://www.theguardian.com/science/2021/jul/19/billionaires...
[3] https://en.wikipedia.org/wiki/List_of_Falcon_9_and_Falcon_He...
Aren't you presuming that Tesla is the only seller of electric vehicles, and those who bought Tesla would thus never even consider buying any other electric vehicle?
I mean, currently Tesla represents around 15% of the overall EV sales, and BYD auto alone representing 21%. This means that as of right now around of 85% of all ev buyers are not buying Tesla.
The opening of Tesla's Supercharger network has been instrumental in making EVs from all manufacturers viable for a broader demographic in the U.S. Moreover, for a considerable period, Tesla struggled to meet the high demand for their vehicles, with many potential owners enduring long wait times to receive their cars. Given the limited and less attractive EV alternatives at that time, it's unlikely that these consumers would have opted for another EV.
In the U.S., where Tesla has a market share close to 60%, Chinese automakers like BYD, SAIC, or Geely have not yet established a significant presence. Thus, most American consumers would not have likely considered these other EVs.
Additionally, Tesla's pricing strategy has exerted downward pressure on the overall EV market, making these vehicles more accessible to the masses. Other manufacturers are indeed emulating Tesla's approach, further acknowledging Tesla's influence on the industry's transition to electric vehicles.
As to the emissions offset calculation, the figures referenced consider each Tesla vehicle as a replacement for a conventional gasoline car. Whether a Tesla purchaser might have considered another EV is irrelevant to the emissions reductions associated with each Tesla vehicle. Also the amount of emissions needed to offset SpaceX emissions is comical and obviously Tesla covers those even with a small fraction of the vehicles they sell.
https://www.cnn.com/2023/04/20/investing/china-tesla-ev-pric...
https://www.businessinsider.com/ford-ev-production-slow-than...
https://www.npr.org/2023/02/02/1152586942/tesla-price-cuts-f...
https://electrek.co/2021/11/08/ford-ceo-praises-tesla-intern...
https://www.cnbc.com/2021/10/28/tesla-is-setting-the-bar-for...
https://electrek.co/2023/06/05/gm-ceo-tesla-lead-electric-ca...
https://insideevs.com/news/652293/ferrari-ceo-says-tesla-was...
You're jumping to conclusions. Just because Tesla exists that does not mean that all hypothetical transitions from fossil fuel to electric should be attributed to Tesla.
I repeat: Tesla is responsible for only 15% of EV sales, and nothing leads to believe that the remaining 85% of the EV market does not serve as a substitute good. Claiming that Tesla is an environment protection messiah is peak corporate worship.
Because it takes two to tango. In both cases "all the credit" or "all the debit" goes to the manufacturer for making the product AND the customer for paying for it.
Though, everyone that bought a tesla, they would have bought a gas vehicle instead? I think that is potentially a very invalid assumption which negates that savings calculation. Yes, EVs can be cleaner than conventional cars, but it still adds an impact. Less bad does not necessarily mean all good.
The mentions of teslas charging network sounds very PR heavy. What if that network flops in 5 years and meanwhile the non-common standard means a global charging infrastructure is never properly developed?
Musk's hyperloop was supposed to be built in a few towns that lost money on the deals and pulled funds from other transit projects. Those transit projects never happened.
I don't think anyone can at all decide whether musk, tesla and his companies are yet a net good without the benefit of more time and 20/20 hindsight.
And self driving taxis, if they ever do make it which is still waaaaay out even by Elon time, are not going to balance it out.
https://www.theguardian.com/us-news/2022/may/29/california-h...
Ok. So you agree Musk tried to sabotage California high-speed rail, but as he failed then... We should ignore it?
- If Musk tried to sabotage something and he failed: his intent doesn’t matter
- But the project that he tried to sabotage probably should have failed anyway
— The Musk Prayer
That's specious reasoning at best. It's absurd how you try to depict a Robber Baron move as a simplistic fiscally responsible stance. It's even sillier once you realize the only reason Elon Musk did his best to sabotage the program was because he believed it would be a success and thus a threat to his bottom line.
I really do not understand this corporate worship nonsense, specially when dealing with this specific corporation.
The only specious reasoning I'm seeing here is the weird assumption that one high speed rail line in California would meaningfully suppress Tesla car sales. It's competing with air travel, not car ownership.
It's ridiculous enough to suggest that it would suppress the sale of cars generally. It's especially ridiculous to suggest that it would suppress sales of Tesla vehicles. It's a 760 mile round trip between SF and LA — not an issue for an EV if you're doing it occasionally. But someone buying a new car for the specific purpose of driving this route simply wouldn't consider an EV.
It had literally zero impact on California High-Speed Rail.
EVs are mostly good over the long term, but they are not an instant win button.
So battery production is a good way to transport energy from where it's cheap to produce to where it's needed, much better than bitcoin.
The main effect of mass is when comparing 2 different EVs: one that is twice as heavy has ~twice the initial production emissions, as well as twice the energy consumption (and emissions, as the case may be). Even with EVs, large and heavy cars are very wasteful.
> Even with EVs, large and heavy cars are very wasteful.
Yes, I am pretty anti-car and anti-big car so sure that is true.
I get what and agree with what your trying to say but a better comparison is needed
I'd like the ability to visit space at some point in my life, and I'd like our species to become experienced at doing things in space. Like, if we need to be able to deploy something in space to decrease the amount of heat we're taking in to try and buy more time to decarbonize before we're completely F'd because of all the people venting potent greenhouse gasses from their HVAC systems, it'd be nice if we already had a space industrial complex capable of supporting that goal.
It seems that most of our most powerful leaders (so-called) are sociopaths or psychopaths.[1] Are people who are pathologically incapable of basic empathy and compassion going to be moved by a joyride to watch the Big Blue Ball? I wouldn’t hold my breath.
The only thing I read about resulting from that trip was Shatner's induced depression over the sight.
Still no astronaut says that they don't want to go back because it contributes to destroying the planet, do they?
Don't get me wrong: I would probably throw my principles out the window if I got to become an astronaut. But I don't think we can say that going in space makes you a big environmental activist.
You certainly mean the direct carbon footprint, right? Not counting what was involved in building the rocket, importing the material, test launches while developing the technology, etc?
> It's not a huge impact compared to how much they advance our understanding of how to live in space
Not sure I get that comparison. So you say "it's okay to contribute destroying life conditions on Earth in this case, given how much it helps us understand how to make people survive around Earth"? We can't move the Earth population to live in orbit once surviving on the ground is impossible, so it's a bit like saying "the carbon footprint of burning tires is not huge compared to how practical it is as a way to get rid of tires", IMO.
We won't, as a species, go live in orbit, we won't go live on the Moon, and we won't go live on March. And we quite certainly will not ever reach the next star (which is what, 4 light-years away?). We don't need to understand how to live in space in order to survive on Earth. And right now we are destroying Earth. We need to first learn how to survive on Earth, and then maybe we can consider playing with human spaceflights again.
> I haven't run the numbers on Starship, but my impression is that it'll be significantly more efficient.
Again, you're missing all the indirect impact, and then all the rebound effects. Every success of SpaceX gets us into a world where the space business (because it is now a business) emits more CO2. I don't know why people don't get the memo, but right now our survival depends on reducing our CO2 emissions, not increasing them.
wrt direct vs. indirect emissions, rockets are incredibly thin cans full of fuel that immediately gets burnt. The direct emissions will almost certainly dominate the embodied carbon from manufacturing, especially when they're launched >10 times. Once you start including the infrastructure, it's less clear, but it's a close-enough estimate for setting the context in an internet comment. Is the value we get from an astronaut doing work in space worth the carbon footprint of a few American families for a year? I think so, I get the sense that you don't agree. That's fine.
You make it sound like we get a lot of value from astronauts surviving in space, and that the CO2 footprint of the space business is almost nothing.
I disagree with both. They don't really make any useful work (that could not be done by robots) other than surviving there, and the carbon footprint of the space business is going to grow much bigger (if those companies are successful) than what you seem to believe.
> it's less clear, but it's a close-enough estimate for setting the context in an internet comment
It surely is convenient to ignore them :-)
Furthermore it’s an issue that affects all launches, by ULA, NASA, ESA, whoever, not just SpaceX.
But sure, go ahead and ignore all of that and make a thoughtless dig against one person, in one country, running one rocket company for the crime of being successful at it.
Journalists are not scientists.
Did you mean FAA rather than FCA?
The FAA did ask SpaceX to do a lot of additional ground level items: https://www.cnbc.com/2022/06/13/faa-spacex-starship-environm...
The reviewers at th ed FCA were unlikely to be in the thousands, the rest mentioned I would completely discount.
The "crime" is that one person is not stopping to ask whether we should. There is a lot of hubris is there. Regardless, nobody should get a free pass to wreck the earth (but this is kittens, putting tons of C02 in the air is generally free, so... yeah...)
Looks like the biggest "green" issue is the rockets burns tons of fuel. Thd FAA review was a green light. This phenomena of punching holes was hopefully considered by the FAA (but at this point, can only hope that everything was at least considered)
My point is there is extensive and persistent oversight, debate and opportunities for input and objection. Journalists play a role in the public interest in any democratic society.
One person didn’t ask whether we should? Space technology has been controversial since its inception. Citizens, journalists and politicians have been questioning it throughout its history. You really honestly think you’re the first person, or this is the first time anyone has stopped to wonder about it?
Incidentally, there’s one particularly famous example of this from 1970 that’s a bit of a classic: https://launiusr.wordpress.com/2012/02/08/why-explore-space-...
Of course nobody should get a free pass to wreck the Earth. That’s a cartoonishly absurd caricature of what’s going on.
>My point is there is extensive and persistent oversight, debate and opportunities for input and objection.
the point that other commentators have made, which has seemingly been ignored, is that being the person with the most wealth in the entire world allows one to ignore a lot of the checks and balances associated with any activity.
A lot of the 'extensive and persistent oversight' comes from 1) internal employees and 2) government officials that have been 'taken out to dinner' enough times that they don't want to lose the opportunity to schmooze with what amounts to be the most and influential people in the world.
this is essentially how all of American aerospace operates, and I speak from personal experience -- most groups don't have the luxury of being a cult of personality on top of the thick wallets, however.
You can call CO2 harmless all you want, but the reality is that we have a tenuous grasp, if any at all, on what spilling hundreds of tons in a minute will add up to [0], and that's only a drop in the bucket compared to the rest of the environmental accumulative 'unknowns'.[1]
In effect Musk's pass to wreck the Earth was by no means free, he paid for it. The problem is that someone , anyone with money and pop interest, can do that.
I'm by no means anti-space, but this trend of pretending that there isn't a sacrifice made on Earth to fuel these mega-ventures is absolutely naive, and the tragedy is that the every-person is going to be the one paying the bill; it won't be Musk's redirected billions.
[0]: https://www.bbc.com/future/article/20220713-how-to-make-rock... [1]:https://cosmosmagazine.com/space/astrophysics/greenhouse-gas...
I read comments like this almost every time SpaceX is mentioned here, and climate crisis extremists bang on about it endlessly. It’s impossible to ignore, it’s just that most people disagree.
>you can call CO2 harmless all you want…
I did not do so, thank you very much. I’m aware of the issues. Climate change is a real problem, but exaggerated histrionics aren’t going to solve problems.
>Musk’s pass to wreck the Earth… pretending that there isn’t a sacrifice being made…
He has no such pass, and nobody’s pretending anything of the sort. See above about exaggerated histrionics. They’re so obviously absurd it does the climate change cause no good whatsoever. To mainstream voters it makes extinction rebellion folks look like a fanatical cult dissociated from reality, and by association undermines the credible and important climate change cause. A cause Musk has probably done more to physically advance through direct personal action than all but maybe a handful of other human beings on Earth.
Journalists are great, but it's not like they have a many million dollar budget to study this. The hole in the ionosphere seems to be news, seemingly this is an area where humanity is missing _lots_ of knowledge.
There are some interesting reads on whether Musk is a net benefit or not (reasonable people can disagree here)
> this brings us to the first fundamental problem: Elon Musk does what he wants and wants everyone else to do the same. He only sees the advantages of his approach, without ever asking himself about the consequences. It is certain that the aerospace industry has played a fundamental role in the study of climate, thanks to the weather satellites placed in orbit. The problem is that Elon Musk wants to multiply the number of satellites by 20, which will directly disrupt space operations and astronomical research.
https://bonpote.com/en/elon-musk-solution-or-nightmare-for-t...
Personally, I think the AI car thing has been a distraction and has been an excuse for continuing to put all of our transport eggs in the single-occupancy-vehicle basket. Had Musk pushed the EV numbers he is pushing now back 20 years ago - I would agree that he had done a lot. As-is, for EVs, I view Musk a bit like Steve Jobs, brought the touch-screen phone forward by several years and helped the market adoption, but touch-screen phones would have happened without Jobs.
There are some other interesting reads too from less biased sources:
> It's not surprising that Musk’s socially-responsible message of warning about environmental crisis combined with his massive capital success building electric vehicles (EVs) has given him a messianic status among some of his many admirers. But this status also means that by attacking the Build Back Better legislation, which is by far the United States’ most significant legislation ever aimed at fighting climate change, Musk is providing ammunition to climate deniers and fossil fuel industry opponents of efforts to protect the U.S. from climate change, create good jobs, and lead the world in technology and policies.
> If Musk is really serious about combatting climate change, we need him to support an all-hands-on-deck approach. The commitments, innovation, and investments of private companies must be matched with government policies and incentives.
https://www.forbes.com/sites/margooge/2022/01/17/where-does-...
And then this article is perhaps the best so far:
https://gizmodo.com/elon-musk-isnt-a-climate-hero-just-becau...
> Let’s look first at Musk’s achievements in both electric cars and solar power, which Manjoo singles out. In many ways, Tesla is certainly deserving of a lot of praise
> Meanwhile, Musk has dismissed the idea of improving existing public transit—which experts say is arguably more important in cutting emissions than popularizing electric cars.
> "I read comments like this almost every time SpaceX is mentioned here, and climate crisis extremists bang on about it endlessly. It’s impossible to ignore, it’s just that most people disagree."
Respectfully, I feel you are responding to those comments, rather than the ones placed here. How can anyone disagree with the statement that the impact of rocket launches on the atmosphere is not well understood. AFAIK, that is fact. If there are such studies, that would be super interesting, to my knowledge, those studies have not been done (and could not be done because nobody was launching rockets at an appreciable frequency for anyone to even study it).
If those studies had been done, I would not expect the punching of holes in the ionosphere to be news.
> You really honestly think you’re the first person, or this is the first time anyone has stopped to wonder about it?
I don't think that, I didn't imply that, and wondering if I was the first person to ever wonder that for the first time is putting words in my mouth.
My question is whether anyone that was in a position to know and was also not being payed off wondered this. Given the lack of science around this, the major players I think are more concerned with going further than they are in really studying exactly whether they should. That makes no sense for SpaceX to devout half of their budget to study why they should not be launching rockets. If they are not studying that, who exactly is?
> Of course nobody should get a free pass to wreck the Earth. That’s a cartoonishly absurd caricature of what’s going on.
There have been plenty of free passes to wreck the earth. Examples are subsidies going out to industries that pollute. These free-passes go back in time, recall the train companies giving free tickets to those that would shoot Bison from the windows of the train. We can also talk about deforestation, that most old growth forests have been chopped down and so many tree farms are now taking their place (tree farms grow overly dense, and very sickly trees that have nowhere near the same positive impact as old growth does). There are so many examples of free passes being given.. Why else are so many rivers toxic and unswimmable? The fact we have so many things and areas that are wrecked serves as counter-point.
Beyond this, I think 'serf' responds pretty well, I will not add further.
Apparently, angstrom was invented exactly for measuring light wavelength.
Its (arguably more common today?) usage for atoms and other microscopic structures actually came after that.
We humans are stupid. We always underestimate the consequences of small stuff that simply adds up over time. This is a pattern. We polluted the planet with forever chemicals, lead, and tons of other pollutants that our descendants will have to deal with and suffer from!
All this needs to be regulated, a risk-benefits analysis made, and there needs to be a huge excise tax for all such activities!
Anyone else have this use of Ångström trigger an exception in their brain? The unit of default for wavelength is nm, not Å… (1nm=10Å)
Anecdotally I've only really heard angstroms used in material science / condensed matter physics, where most small structures are small integer numbers of angstroms across.
And the Starlink sats are so low that they dont really turn very meaningful debris ever.
And in general, yes LEO can handle millions of sats.
We have like 150k cars in a single tiny country on earth right now.
Cars, for the most part, follow the road and the direction they're already going. They (usually) signal if they're about to make changes. And to be safe, we've built an arrangement that they only travel on these specific paths at specific speeds, modifying their speed to match the other cars they might hit.
The challenge with satellites is that steering is hard and very limited. And they don't have brakes they can slam to come to a stop if they need to suddenly avoid a collision.
> And to be safe
Tell that to the 40k people killed and the millions hurt by cars in the US alone.
Cars constantly turn and intersect routes with other cars without any planning, even if perfectly handled and most of time they are not.
> The challenge with satellites is that steering is hard and very limited. And they don't have brakes they can slam to come to a stop if they need to suddenly avoid a collision.
They don't need to break, they just need to know the position of speed of other objects and correct position ahead of time.
The only reason why this is even a program at all is because only the US has even minimally invested in monitoring. If each nation just did the same our accuracy would be far, far higher and things would be way better.
So, as of now, we have minimally invested in solving this problem and it isn't a big issue. Slightly more investment (that is justified if we 10-100-1000x the amount of sats) is required eventually.
But compared to what it takes to make cars not crash into each other its nothing.
(Unless its like US infrastructure design that seems to want to make cars crash into things, but I hope in Space we can avoid that)
Collision avoidance in LEO is quite elegant. When two satellites are predicted to pass uncomfortably close to one another, one satellite will fire its station keeping thrusters to raise its orbit above the other. No brakes or swerving needed, just a slight push well ahead of time. Starlink sats do this over 1000 times per week.
Even better, energy used for avoidance reduces energy needed for station keeping on a 1:1 basis. Avoidance maneuvers are effectively free.
Starlink initially used Krypton for its thrusters. But they have now switched to Argon since its incredibly cheap and available. Xenon for a long time was the standard, but its to expensive and rare.
Some sats also have chemical power, often a Hypergolic propellant, like dinitrogen tetroxide plus hydrazine. Specially for larger sats this is the case.
- https://en.wikipedia.org/wiki/Ion_thruster
-
Mind you I'm not the one who came up with the TERRIBLE analogy with cars. Millions of people a year die in car accidents, and this was somehow the example that's supposed to convince us that if "cars are safe" then satellites travelling 100x faster than a car over our heads (and 10x faster than an airplane) are also safe. The whole construct betrays extremely sketchy thought process.
Is that right? Scientific American seemed to think it could be a problem in 2019[1]. Space.com says Starlink satellites orbit at an altitude of about 342 miles (550 kilometers)[2]. And the Wikipedia article on Kessler Syndrome[3] (which is a chain reaction of satellite debris) mentions an incident at 555km that was problematic:
"In 1985, the first anti-satellite (ASAT) missile was used in the destruction of a satellite. The American 1985 ASM-135 ASAT test was carried out, in which the Solwind P78-1 satellite flying at an altitude of 555 kilometres was struck by the 14-kilogram payload at a velocity of 24,000 kilometres per hour (15,000 mph; 6.7 km/s). When NASA learned of U.S. Air Force plans for the Solwind ASAT test, they modeled the effects of the test and determined that debris produced by the collision would still be in orbit late into the 1990s. It would force NASA to enhance debris shielding for its planned space station."
[1] https://www.scientificamerican.com/article/spacexs-starlink-...
The real danger is space junk that's at much higher altitudes. OneWeb and Telesat Lightspeed (in planning) operate at 1000+ km, where space junk will take 1000+ years to deorbit on its own. And OneWeb has already had a satellite failure where it can't deorbit the satellite.
The real concern for meaningful space debris issues is in the regions where decay requires 100+ of years.
The articles mentions the ASAT because that's what they used to study orbital behavior and decay.
Also generally, Space.com is universally agree to be the single worst 'space news' page known. I would never use it as a source for anything.
waste -> vast
But for anyone who's not 100% comfortable with English, "the vast majority" is not simply a case of a descriptive adjective modifying the noun "majority," but it's actually a common phrase. People don't say "the big majority" or "the large majority," it's specifically "the vast majority."
If you wanted to use a different adjective, you could say "a large majority," and that would mean something like "most but not all and the 'but not all' is kind of significant" where as "the vast majority" means "nearly all of them, and the 'not all' is insignificant."
Compared to that, anti-satellite missile bust a satellite into pieces and carry indeed the danger of creating a Kessler syndrome. In case these would be used on a large scale, WW III would be imminent anyways. Apart from that, missiles are too expensive to knock out Starlink satellites, and the latter are comparatively easy to replace.
Debris in a crowded orbit will eventually collide, no matter how synchronized it all was initially.
> Debris between 1 cm and 10 cm (approximately 500,000), referred to as the “lethal” population, are the most concerning as they cannot be tracked or cataloged and can cause catastrophic damage when colliding with a satellite. Objects smaller than 1 cm (approximately 135 million measuring from 1mm to 1cm, and many more smaller than 1 mm) that could disable a satellite upon impact are termed the “risk” population
It’s pollution of the upper atmosphere on a huge scale and we don’t know what side effects that will produce
That’s fun! Of course, we do already have something analogous to FAA altitude separations. But that requires everyone everywhere to cooperate in real-time, and mandates some degree of maneuverability. I guess orbital decay is only a concern for aircraft when they aren’t trying to land.
What you have to watch out for is the eventual rise of the Kessler Cult, who (according to me) will seek to block all access to space intentionally ;)
(They can just be awfully hard to count, no matter who counts.)
Glad to hear it! Because I know a large family that doesn't have a computer. I'll send you their address so you can mail them yours!
You think that all government, education, banking, employment, and healthcare web sites work on phones or have apps? That's adorable!
The fact is they have a device that connects to the internet, shifting the goalposts in the argument does not make that less true.
Astronomy is already a casualty as the sky stops being "dark". I guess who cares about fundamental knowledge when there is profit to be had.
[1] https://www.space.com/astronomers-urged-protect-dark-skies
The more reassuring answer could be "there's already regulation Y that stops any single company from causing too much damage."
https://news.ycombinator.com/item?id=33762492 ("North Korean ICBM launch detected using GPS")
When we fly drones especially BVLOS operations we sometimes encounter some GNSS anomalies, that in some cases we just cancel the mission that day and the next day it’s with no issues. Could it be that’s the reason? Who knows, but it might be an issue later with crewed drones.
Getting what is probably the cheapest tier of spectrum analyzer and investigating that behavior seems somewhat prudent.
The term "punching a hole" is absurd, IMO.
Does anyone else feels it’s a good thing?
On one hand, Science™ sez it fixes itself every morning. On the other, Elon Bad and Planet Good.
So, I'm torn.
The signal might propagate and alert other intelligence that we are attempting something challenging.
Hopefully they send help.