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
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.