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

  • nevemsenki@lemmy.world
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    5 months ago

    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?

    • puchaczyk@lemmy.blahaj.zone
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      5 months ago

      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.

    • nialv7@lemmy.world
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      5 months ago

      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.

      • intensely_human@lemm.ee
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        5 months ago

        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.

    • Cocodapuf@lemmy.world
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      5 months ago

      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.

    • gian @lemmy.grys.it
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      5 months ago

      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.

      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.

      What could go wrong?

      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 ?

      • Peppycito@sh.itjust.works
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        5 months ago

        maybe to wait to have at least some hard number looks like a good idea.

        Good plan. So they’re holding off on starlink launches to let the science catch up, right?

      • dustyData@lemmy.world
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        5 months ago

        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.

        • gian @lemmy.grys.it
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          5 months ago

          Perfect is the enemy of good.

          I agree on this.

          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.

          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.

          Doctors don’t wait for the worst before starting treatment.

          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.

          Specially if corrections carry none or way less risks than what is currently being done.

          Hard to decide that corrections carry lower risks of something we don’t understand.

        • intensely_human@lemm.ee
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          5 months ago

          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.

    • chemical_cutthroat@lemmy.world
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      5 months ago

      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.

      • nevemsenki@lemmy.world
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        5 months ago

        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.

      • gaael@lemmy.world
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        5 months ago

        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

        • chemical_cutthroat@lemmy.world
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          5 months ago

          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.

          • gaael@lemmy.world
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            5 months ago

            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.

      • intensely_human@lemm.ee
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        5 months ago

        “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.