Abstract from the paper in the article:
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109280
Large constellations of small satellites will significantly increase the number of objects orbiting the Earth. Satellites burn up at the end of service life during reentry, generating aluminum oxides as the main byproduct. These are known catalysts for chlorine activation that depletes ozone in the stratosphere. We present the first atomic-scale molecular dynamics simulation study to resolve the oxidation process of the satellite’s aluminum structure during mesospheric reentry, and investigate the ozone depletion potential from aluminum oxides. We find that the demise of a typical 250-kg satellite can generate around 30 kg of aluminum oxide nanoparticles, which may endure for decades in the atmosphere. Aluminum oxide compounds generated by the entire population of satellites reentering the atmosphere in 2022 are estimated at around 17 metric tons. Reentry scenarios involving mega-constellations point to over 360 metric tons of aluminum oxide compounds per year, which can lead to significant ozone depletion.
PS: wooden satellites can help mitigate this https://www.nature.com/articles/d41586-024-01456-z
Before anyone jumps on the Anti-Musk train, read the article, please. They admit that they don’t understand the complications that could arise and that they don’t have any hard figures for the damage being caused. I’ll be the first to jump in and say that it’s probably a bad thing to just let metals burn in in atmo, but let’s make sure we discuss the facts, and not just the politics of the potential polluter.
Ah yes, the usual method of waiting until the issue becomes confirmed and also way too severe to fix instead of acting on precaution and harming profits of private companies. What could go wrong?
Yeah, PFAS comes to mind. It took decades to confirm it’s harmful to humans but at this point it is everywhere and hard to get rid of. Worst part is they try to use other chemicals to replace PFAS, but again how harmful they are we don’t know and we will learn that decades later too because companies don’t want to make long term research before releasing the product. Enviroment shouldn’t be a billionaire’s testing ground.
So if moving from PFAS to alternate chemicals means moving foolishly into untested chemicals, why didn’t they wait to test them? Were they forced to make the change?
There is a line somewhere I think. Like people weren’t 100% sure the atomic bomb won’t ignite the atmosphere (it’s only very unlikely), but they still tested it. Similarly the probability of creating micro blackholes at LHC is not zero either, yet they still ran it.
If we have to make sure everything is 100% safe before we can do anything, we will be stuck with the status quo.
We will die of starvation because nothing is 100% safe, so waiting until we find that level of safety means we just won’t do anything.
I don’t know how that is usual in your mind. Since from my perspective I see it constantly.
As opposed to acting before you understand the effects of your actions? Neither seem like good choices.
Probably the best option would be to research harder. Make the polluter fund a much larger scale research program to understand the problem and viable solutions as quickly as possible.
No, but as even them don’t understand what the complications are and how much the damages could be, maybe to wait to have at least some hard number looks like a good idea.
And what could go wrong if we start to fight a problem that we don’t understand how big it is, maybe using the wrong solution on a wrong scale ?
Good plan. So they’re holding off on starlink launches to let the science catch up, right?
Perfect is the enemy of good.
If it is worth doing, it is worth getting it done, even if we aren’t 100% certain or ready on a lot of things. Doctors don’t wait for the worst before starting treatment. Specially if corrections carry none or way less risks than what is currently being done.
Doing scientific experiments to understand the risks is worth doing.
One of the big risks of not having a global communications satellite network is that people can get cut off from the internet by land-based ISPs loyal to whatever local government they’re trying to be free of.
So there’s a danger of just saying “no satellite clusters”.
We’re always balancing dangers against other dangers. There’s danger in not acting, not growing too.
I agree on this.
From the article it seems we are not even 10% certain. In summary, we don’t understand (yet) the problem, we have no clue on how complex is, we have no hard number to tell us how big it is.
I agree, something need to be done. But for now the “something” is just to try to understand better the problem, or at least how big it is.
True, but they start treatment when they know what they need to cure or at least they have solid evidence that indicate something, not before.
Hard to decide that corrections carry lower risks of something we don’t understand.
Nah, this is a different method. It’s the one where we get all of the facts before we take action. Maybe you aren’t up on it, but knee-jerk is so 1700s.
We don’t have to wait until it’s “fully confirmed” to start being concerned about it. Remember climate change denial? We were in the “we don’t know if humans are causing it” phase for a while.
I also agree, let’s not jump on the anti-Musk team for this, but satellites burning up has always been a rather obvious source of pollution, and it’s good to see more discussion on it
We were in the “we don’t know if we’re causing it” phase for a long time because big oil knew about global warming and deliberately ran disinformation campaigns so they could keep profiteering. Had Exxon done the right thing in the 70s we wouldn’t have this looming crisis.
And now we’re in the “is burning up thousands of satellites bad?” phase of space exploration. I’ll be waiting for spacex to do the right thing.
Don’t get me wrong. I’m not defending corporations here. I’m simply stating the fact that climate change denial wasn’t the case of waiting until it’s “fully confirmed”, it was pretty much confirmed back in the 70s. They even had predictions for the next century on how things will go bad if nothing is done and the last time I checked we were pretty on course with their predictions. When it came to the scientific consensus, it was pretty much “fully confirmed”. It was simply the public opinion where it wasn’t “fully confirmed” because corporations deliberately ran disinformation to make it seem like scientists didn’t know what they were talking about.
But this paper isn’t really confirming anything. The paper itself says that the model does not account for all the factors and to literally quote the paper:
This paper is not presenting a final conclusion, it’s presenting concerns that need further studies. let’s wait for further studies and if there’s scientific consensus about it being an issue I’m all for bringing out the pitchforks. In the mean let’s keep calm and dread over the doom and gloom that is climate change.
It’s highlighting a potential significant risk. Major ozone loss is much worse than lack of internet. The high uncertainty of the paper is easily offset by the harm that would be caused if the paper is correct.
So what are we supposed to do, halt all space flights until we figure this out?
Without further research going into how much damage it’s doing there’s no way to say what our next steps should be. Maybe everything we’re doing is still within acceptable limits? Maybe we need tighter regulation on materials going into space. Maybe some materials need to be outright banned.
The only reasonable thing we can do is study it further. Expecting instant result based on one study that only outlines a potential risk is quite frankly just doomerist behavior.
Well, maybe it’s offset. It’s hard to say whether A > B or B < A when you don’t know the value of either one.
So you’re saying that in the 70s they had predictions about how things will go bad for the next century?
Where are these predictions? It’s been 50 years so at least some of these predictions should be checkable now.
I would feel so much better if I could see some examples of climate science predictions being proven accurate.
It’s pretty public knowledge by now. If you search “ExxonMobil climate prediction” I’m sure you can find a starting point. I recommend finding all the Exxon papers because they’re quite eye opening.
Yeah, and now despite what the scientists say, everyone believes climate change is going to render Earth uninhabitable, and we are taking massive steps to avoid the problem as if it were an existential threat, which the science again does not support.
We’re treating climate change as if it were as serious as a planet killer asteroid, and we’re massively violating people’s rights as if it were.
Can’t tell if this is sarcasm, orr
Sure, PFAS were also considered a nonsignificant issue until they weren’t, only it’s too late to unfuck it now. Well, no harm in generating more potential ticking time bombs I guess.
Like maybe wait a few years and finance some science to check that your mega constellation of satellites (built to fail after only a few years to make sure your rocket company never goes out of work) won’t be a fucking nuisance on so many levels before you actually launch them ?
This “get all the facts before taking action” ?
Edit: I think I knee-jerked
Oh, you mean a study on the Satellite Internet Constellations that have been in orbit since the 1990s, a full 30 years before Starlink launched? As with nearly everything else, Musk isn’t the first to do whatever he does, he’s just the loudest. If Starlink hadn’t launched we would still be facing the same problems. Thankfully, he’s a big enough ass that he makes a easy target for these kinds of things.
Maybe I didn’t get my facts straight, but iirc there are around 7.5k satellites up there, with starlink current count about 5.5k. And I think I read they got the greenlight for the 7.5k gen 2 sats launches.
That looks like a scale change to me. Associated with the short lifespan (which contrasts with the situation 30 years ago, where launches were more expensive), it’s kind of a new situation and should have warranted a more careful approach.
So musk isn’t the first one to launch satellites, I agree. But the way it’s done is kinda new, and mostly on the worse side. And I’m not saying the old way was good, and not absolving previous actors from responsability in the pollution.
“All the facts” is counterfactual, superstitious thinking. There is no such thing as “all the facts”, except in game theory examples like tic-tac-toe.
In all realms other than small mathematical models, there’s no circumstance under which one has all the facts.
I was actually reviewing the O3 depletion process https://en.m.wikipedia.org/wiki/Chlorine_monoxide and Cl only stops reacting with O3 when it ends up as ClO2, but that is rare, because ClO usually is too short-lived to react with another Cl into Cl2O, so it may be possible that a catalyst like Al2O3 could actually clean up Cl interfering with the ozone layer along with the effect of speeding up the nefarious reaction with O3 :D
The irony of a wikipedia expert agreeing with a tabloid skeptic.
Why did you write that? What do you gain or anyone reading from that comment? Who are you performing for? Where is the audience? Are you bored and I’m your little punching bag? If you know, contribute and tell us if and why I am wrong and I will welcome it, if you don’t or it is not worth the effort, just stfu, nobody needs your shit snark.
I wanted to reinforce good behavior, punish bad behavior.
Nah man, that’s just toxic hurtful criticism. Let people brainstorm and just let go of the gavel.
Sure I admit that your mistakes were purely imaginary and we can all pretend you never made them to hide your shame.
You didn’t mention any mistakes though
o7
Guys, let’s not jump into conclusions. I’d say that it is not a real issue until at least a billion people have died from it.
If they don’t have grounds to accuse SpaceX then SpaceX can sue them for defamation. SpaceX doesn’t need YOU to defend them.
OP listed the referenced study in the description, it has “hard numbers” from simulations and citations to many other studies as well.