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.
One thing to note - The science is still calculating. Yet. SpaceX (and presumably others) are allowed to continue and increase what they're doing. This is the bass ackwards way to protect future us.
Its the same mentality as driving in a random direction for 20 minutes while someone looks in the car for the map on the off chance that when you get the map open you'll be where you wanted to be anyway.
It has the potential (and at this point, just the potential) for planet level changes, and is being done by one group. Should I, a random dude, be able to do something that might possibly affect the entire planet, and the planet as a whole just have to wait and see how it turns out?
The hopeful thought that its probably nothing, before anyone can prove that it's probably nothing, makes a bet where the short term wins are mine, but any long term losses are everyone else's.