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SpaceX's Starlink May Be Keeping the Ozone From Healing, Research Finds (futurism.com)

submitted 4 months ago* (last edited 4 months ago) by Gsus4@programming.dev to c/technology@lemmy.world

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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

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[–] Dasus@lemmy.world 1 points 4 months ago (1 children)

Afaik, high internet speed requires higher frequencies and high frequencies reach less far + have less penetration through/around obstacles. That's what makes providing "4g" virtually everywhere easy (good enough for phone calls at least), but if they want to provide actual high speeds everywhere, then it suddenly becomes not so easy (nor cheap).

Why are you putting "4g" in quotes? It is 4g. Basic cellular networks cover the entire country, and using 4g speeds has been common for a long time. Hell, back when I was in the army, I had a laptop with a mobile connection. It was 3g back then, but it worked, even from the deepest of woods we were in.

The terrain of Finland probably makes this easier for us, as this is a rather flat country. We have literally no mountains. A few fells (=large hill, essentially) , but no mountains.

[–] RunawayFixer@lemmy.world 1 points 4 months ago

The quotes are there because it's a common misconception that as soon you have any kind of 4g signal, you have access to a fast connection, which is not the case. So in many countries at some point they proclaim that "xx%" of the population now has access to "4g", which will be technically true, but the actual % that has access to fast 4g will be substantially lower.