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

  • @chemical_cutthroat@lemmy.world
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    -115 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.

    • @OsrsNeedsF2P@lemmy.ml
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      125 months ago

      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

    • @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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        -25 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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          25 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.

    • @nevemsenki@lemmy.world
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      45 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.