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burning satilites making magnetic shunt?

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coppercone2:
not sure how well alumina is made in a vacuum or low partial pressure. aluminum oxidizes pretty darn slow. not much O2 there either.

SiliconWizard:

--- Quote from: coppercone2 on March 17, 2024, 08:49:25 pm ---not sure how well alumina is made in a vacuum or low partial pressure. aluminum oxidizes pretty darn slow. not much O2 there either.

--- End quote ---

yes, I'm wondering how you oxidize metals up there as well. :-//

DavidAlfa:
I don't think so when hitting the atmosphere at 17000mph, melting and coming apart at several thousands of degrees,  plus ozone is an extremely potent oxidant (Supposing it reaches that atmosphere layer).

From this article:
https://www.pnas.org/doi/full/10.1073/pnas.2313374120?_ga=2.213978450.492158759.1697570369-891100340.1697570369

--- Quote ---The metal atoms that are produced by meteoric ablation become oxidized below 85 km, and the resulting compounds condense into nm-sized meteoric smoke particles
--- End quote ---

And:
https://aerospace.org/article/satellite-reentry-manipulating-plunge

--- Quote ---The first major breakup generally occurs at an altitude between 74 and 83 km. At this point, the object fractures into several smaller objects.
--- End quote ---

coppercone2:
it says they cover 400-50 miles above surface. that only takes care of a thin slice. 350 - 35 = 315 miles left

twospoons:
Just for fun, lets put some numbers on it.
Orbital altitude for Starlink is 550km, and the radius of earth is about 6300km. If the satellites were turned into a monatomic vapor shell 1m thick, the volume of that 1m thick shell would be 6x1014m3
The satellites weigh 260kg, and there are about 5500 of them for a total mass of 1430000kg
If we make the stupid assumption that the whole mass is aluminium, then apply the ideal gas law, assuming a temperature of 273K (it varies from -65C to 125C in LEO) the pressure of that mass monatomic vapor of aluminium spread into that huge volume is just 3x10-19 Pa.

For comparison, the gas pressure in low earth orbit is already 1.3x10-5 Pa.  That's 14 orders of magnitude higher than our vaporized satellites.
Which really means that even if we vaporized every satellite and bit of space junk currently in orbit, and stuffed it all into the same orbital space it would make fuck all difference to the gas pressure already present.

You could, however, turn the starlink satellites into a loop of wire at 550km altitude, and there are enough of them to make a wire just shy of 4mm thick that would go right around the planet.

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