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Will satellite megaconstellations weaken earth's magnetic field?

spaceweatherarchive.com

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Re: Will satellite megaconstellations weaken earth's magnetic field?

#91

Plasma physicist here. While this is an idea worthy of study, the answer to the (spaceweatherarchive.com) title question is "no". The researcher's article makes simple errors in what they call " undergraduate physics" (electricity and magnetism), in basic plasma physics, and in basic algebra. As one straightforward example, their estimate of the (change in) Debye length ignores that their equations (2 and 3) are in t…

That said, we're supposedly overdue for a field reversal, which may make the whole field go out on its own:

https://en.wikipedia.org/wiki/Geomagnetic_reversal

So satellites or no, something might happen to it anyway.

Re: Will satellite megaconstellations weaken earth's magnetic field?

#92

First thought that struck me was the Star Trek Episode where the scientist found out Warp Drive was weakening space-time, so that it could 'rip open'. The scientist were shunned, but eventually did prove it. But even then, the Federation could not "stop" using warp drive. It was one of first instances I saw that even in Star Trek, with all the high ideals, once confronted with something that would shut down progress…

That's interesting, the theme comes up in Starfield as well.

Re: Will satellite megaconstellations weaken earth's magnetic field?

#93

Earlier quoted context omitted.

> But don’t satellites have toxic components? That depends on how you define "toxic". If you mean toxic fuels, most do not. However the idea is just terribly impracticable. Heat shields are heavy and more than that you would need to design your satellite around the heat shield. It would need to be able to fold up like origami into the heat shield. You also need to add extra fuel to perform the targed re-entry. This w…

>If you mean toxic fuels, most do not. Hydrazine is quite common and quite toxic, of the "seek medical attention immediately" variety. 1 ppm is a threshold for exposure for a few hours, satellites can launch with hundreds of pounds of the stuff. A crashed satellite would not be safe to be around, you might get liver failure if you go poking around one and get a good ammonia-like whiff of hydrazine.

Hydrazine is certainly on some satellites, but by numbers of satellites launched and by mass of satellites launched hydrazine is not on a minority of them. Most satellites being launched by mass and number are now Starlink satellites which don't have hydrazine. Even then, the second largest category of satellites is smallsats and cubesats which often have no propulsion at all or use cold gas.

Re: Will satellite megaconstellations weaken earth's magnetic field?

#94
post #34

The paper from this article says that only 450kg of charged material from meteorites enters the relevant part of the atmosphere each year. Yet the total amount of meteorites entering is somewhere in the range of 10^7 to 10^9kg per year [0]. I know the really small stuff slows down too quickly to burn up completely, but does anyone know why such a small fraction of the meteorites burns up in this region compared to sa…

But burning up doesn't make them disappear - the resulted compounds will still be in the atmosphere. Doesn't that matter?

That’s tomorrow’s problem! /s

Re: Will satellite megaconstellations weaken earth's magnetic field?

#95
post #39
post #19

Earlier quoted context omitted.

Almost every technology gets assigned its own existential crisis. I’m not sure what that’s about. (I trace it all back to Jurassic park. It trained an entire generation to be afraid of technology.)

> It trained an entire generation to be afraid of technology. Apparently not enough, given where we're headed.

It's still weird to me how quickly and completely discourse around privacy on the internet shifted from "who are these scary anonymous internet people in chat rooms and why you shouldn't tell them anything" to "routinely publicly post just about everything about your life"

Re: Will satellite megaconstellations weaken earth's magnetic field?

#96
post #4

I for one would like to see the satellites modified with a heat shield so they could punch through and hit a designated deorbit zone. I would even offer my backyard, but I fear it's too small. Wouldn't that be the ultimate tourist attraction? "Witness the next deorbit round tomorrow at Crater Park Observatory!"

they kinda already do, there's a place called the spaceship graveyard where de-orbiting craft target to avoid collisions with inhabited areas https://en.wikipedia.org/wiki/Spacecraft_cemetery I've often wondered if you could take out a boat there to see a particularly impressive de-orbit. Maybe when they do the ISS, which is scheduled to go there eventually. There have been cases where craft ended up in inhabited are…

I remember watching a video of people on a boat waiting for the fireworks of a satellite overhead.

Re: Will satellite megaconstellations weaken earth's magnetic field?

#97
post #34

The paper from this article says that only 450kg of charged material from meteorites enters the relevant part of the atmosphere each year. Yet the total amount of meteorites entering is somewhere in the range of 10^7 to 10^9kg per year [0]. I know the really small stuff slows down too quickly to burn up completely, but does anyone know why such a small fraction of the meteorites burns up in this region compared to sa…

But burning up doesn't make them disappear - the resulted compounds will still be in the atmosphere. Doesn't that matter?

> the resulted compounds will still be in the atmosphere

Why you think so?

Re: Will satellite megaconstellations weaken earth's magnetic field?

#98

The study in question HAS NOT been peer reviewed. https://arxiv.org/abs/2312.09329 Edit: And I'll add arxiv doesn't really vet the content beyond minimal moderation. If it sounds scientific then you can get on arxiv. https://info.arxiv.org/help/submit/index.html I don't think people should pay much attention until that happens. This person has never published a paper before and she's the CEO of a company selling "sol…

> The study in question HAS NOT been peer reviewed

You first seen this!

Re: Will satellite megaconstellations weaken earth's magnetic field?

#99
Question to all here: anybody (except me) learn plasma physics and understand what author write about?

Only I see so obvious mistakes in physics?

1. Debye length DECREASE is harmful, but he talks about INCREASE.

2. When aluminium vapor become conductor? Why aluminium should be vapor there? And why author think, all these THOUSAND tons of vapor should lift to 400km from 60-70km where satellites really burning?

Re: Will satellite megaconstellations weaken earth's magnetic field?

#100

Plasma physicist here. While this is an idea worthy of study, the answer to the (spaceweatherarchive.com) title question is "no". The researcher's article makes simple errors in what they call " undergraduate physics" (electricity and magnetism), in basic plasma physics, and in basic algebra. As one straightforward example, their estimate of the (change in) Debye length ignores that their equations (2 and 3) are in t…

You first plasma physicist in this topic. I'm electronics engineer, but learn plasma physics also, so I also see very obvious mistakes.

But I also have ballistics knowledge and know about Sun wind and light pressure on particles, and I bet, just light pressure is enough to clear space from powder in very short time. Even if threat is real, will need just few months to clear space from dust.

Simple physics suggests, macroobjects, like satellites of classic size (kilograms and tens centimeters) could for long time be on orbits, because high ratio of mass to square, but microparticles (micrometer scale or less), have much less mass to square ratio, so light just blow them away.

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