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submitted 2 weeks ago* (last edited 2 weeks ago) by Gsus4@programming.dev to c/technology@lemmy.world

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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[-] Hadriscus@lemm.ee 40 points 2 weeks ago

damn, starlink is my only way to access the internet. I wish there were an alternative that's usable. Traditional access providers don't work and cell data is extremely slow and there's no coverage where I live. I pay for Starlink with a bitter taste

[-] Dasus@lemmy.world 21 points 2 weeks ago

Might I enquire as to where this remote location might be?

Like on a general basis, no need for addresses.

As a Finn I'm forever spoiled in terms of wireless coverage. We got tons of solitary forests. But you can get an internet connection in literally all of them.

97% of the country gets 4g. And not of the people. The country.

[-] enbyecho@lemmy.world 17 points 2 weeks ago

I live in rural California. We only just this year are able to pick up a faint LTE signal. I think it might get us a very unstable 1-2 Mbps if we hold the phone just right. We have no cable, DSL or other land-based options and because of the topography can't pick up the local wireless provider, which is very expensive anyway - like $175/month for 50/5

So without Starlink our only options are crappy regular satellite providers like Hughesnet which impose very low quotas - 10 GB monthly for day time usage - and have insane latency.

It bugs the shit out of me I have to give money to that fuckwit but without it we live in the dark ages.

[-] Hadriscus@lemm.ee 12 points 2 weeks ago

We're in Mayotte. Two undersea cables connect us to nearby continents (cf submarinecablemap.com) but they're down most of the time. We haven't had a connection in the last six months so we finally subbed to Starlink. Well, strictly speaking there was a connection but it would take anywhere between 5mn to 15mn to load the text of a static webpage, no images or anything else... forget about sending data, using forums... I had to get out and walk uphill for a minute or two to use my phone's cell data

[-] jj4211@lemmy.world 9 points 2 weeks ago

My family has Starlink, they live in mountainous rural. Cell towers aren't too far away, but mountains get in the way of decent signal. No one is running any cables their way, despite a local telco taking money explicitly for providing internet service.

[-] Dasus@lemmy.world 1 points 2 weeks ago

We Finns don't have any of those pesky mountains.

[-] nyctre@lemmy.world 5 points 2 weeks ago

Rural US most likely. Place is too big, too few people to be worth for comoanies to invest. So many places only have 1-2 providers at best, afaik.

[-] TheGalacticVoid@lemm.ee 3 points 2 weeks ago

What about the remaining 3%?

Also, to (hopefully) answer your question:

Ignore Finland/Europe for a second and look at North America. The US has many population centers along the coasts and very few in the west inland. People still live there, so they need internet access, but oftentimes there aren't enough people to justify expanding coverage across such a huge area without subsidizing said coverage with government funds or other customers, so there are bound to be coverage gaps if you don't have unlimited money to throw at the problem. If you take a look at Canada, you can see how much worse the problem is as they have even more area to cover, and it reflects in the fact that they have some of the highest wireless prices in the world.

Also remember that these are wealthy countries. Plenty of other regions have the same problems with population density and physical size, and they can't throw money at the problem like we can.

The TL;DR is that these deadzones exist in a ton of places because a lot of low-population areas are physically huge.

[-] Dasus@lemmy.world 1 points 2 weeks ago

I remind you that it's the remaining 3% of the country, physically. It's not 3% of the population. It's just some places in Lapland which don't have the greatest coverage. And the 97% figure is 4g, 3g has better coverage.

The Northern part of Finland is very sparsely populated and people like internet and cables are very labour-intensive compared to setting up mobile network towers.

But yeah, compared to the US, we're not really that sizable. We're like the size of Montana or so, and they've around a fifth of our population.

tldr Yeah, it is about the size, but also, with Nokia and so on, we've sort of quite a lot of good know-how on building wireless networks. We're the most sparsely populated country in the EU, but I think there's quite a lot of Spain where there's much worse coverage.

[-] Bitflip@lemmy.ml 3 points 2 weeks ago

At least one hour outside any Midwest city.

[-] rab@lemmy.ca 2 points 2 weeks ago

We are in the mountains in rural Alberta

[-] Hadriscus@lemm.ee 1 points 2 weeks ago

lol that's fantastic. Out in the forest with internet. How come, cell towers are closely packed ?

[-] Dasus@lemmy.world 1 points 2 weeks ago

~75% of the country is forest, so it's kinda hard to not be in a forest.

Idk if they're closely packed.

https://elisa.fi/kuuluvuus/

Coverage map.

[-] ILikeBoobies@lemmy.ca 0 points 2 weeks ago

Majority of Canada is like that

this post was submitted on 17 Jun 2024
703 points (95.8% liked)

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