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Wouldn't it be more efficient to just implement some kind of recycling of old satellites rather than letting them burn up at all. Making them out of wood doesn't seem like a good solution.

But wouldn't the wooden one catch fire and unlike aluminium it won't just stop burning after it enters the atmosphere would it ?

EDIT :Oh i just got it its a satelite they don't have to bring it back i think

If you read the article, it's because the tiny particles of carbon from the wood are less damaging for the environment then filling the upper atmosphere with aluminum particles when they burn up upon reentry.

They don't last very long though, they are not particularly energy efficient, and they are single story.

It's not like they have a superior manufacturing technique.

Still do.

Yeah, but those reentry particles are over the middle of the ocean, and the amount currently is absolutely tiny compared to things like meteorites. I'll look in the article, but how do they anticipate high altitude metallic particles effecting the environment?

Edit: I can't find the research paper they were referencing that aluminum particles deplete the ozone layer. It had a redirect link, but my browser couldn't open it. starlink-satellite-reentry-ozone-depletion-atmosphere

E2: looks like it might be this paper? https://www.pnas.org/doi/full/10.1073/pnas.2313374120

We have not identified any definite implications of the presence of these metals in stratospheric sulfuric acid particles, but there are a number of possible effects. One potential effect would be if aluminum and novel elements affect the nucleation of ice or nitric acid trihydrate (NAT). Novel ice nuclei can have a large effect even at low concentrations because polar stratospheric clouds nucleate on a small fraction of the particles (19). Analogues of meteoric inclusions in sulfuric acid have been shown to be ice nuclei (20, 21). Metal cations can also induce efflorescence in aerosol particles (22). The results in this paper prompted us to reanalyze some of our own older mass spectra. We have identified spacecraft reentry particles in ice residuals from high-altitude cirrus sampled in 2002, although not at a notably different frequency than meteoric elements. There is also a possible impact on the size distribution of the stratospheric aerosol layer. Although the spacecraft reentry metals are mostly found in particles with meteoric material, that does not necessarily mean that the number of particles is constant. Larger particles coagulate less rapidly than smaller particles, so adding anthropogenic material to meteoric smoke can increase the number of particles. If so, the sulfuric acid would be distributed into more numerous but smaller particles with different light scattering and radiative forcing. With a great variety of metals present, novel stratospheric chemistry or unusual optical properties are possible. The metal concentrations are low enough that there would need to be a catalytic cycle for a significant effect on chlorine partitioning in the stratosphere. Copper is a transition metal for which the spacecraft reentry flux already exceeds the input from meteoroids (13) and will continue to increase. Until the perturbations caused by such aerosols are better understood, they represent a growing uncertainty for the stratospheric aerosol layer. These mixed meteoritic and spacecraft reentry particles will eventually reach the surface but the mass fluxes are generally small compared to tropospheric sources. For example, the global flux of aerosol lead from spacecraft reentry is less than two tons per year compared to atmospheric emissions of over 700 tons per year from just the United States (23). Copper is one element where spacecraft reentry could be an important source. Reentry elements are concentrated over the poles in the lower stratosphere (Fig. 4) and then deposited to the surface at mid- to high-latitudes. If 10% of the copper vaporized in a future reentry scenario (13) were to be deposited on Antarctica, it could possibly double the concentration of copper in Antarctic snow as roughly estimated from total snowfall (24) and copper in recent snow (25). At present, the refractory material in stratospheric particles is mostly iron, silicon, and magnesium from the natural meteoric source. However, the amount of material from the reentry of upper-stage rockets and satellites is projected to increase dramatically in the next 10 to 30 y (13, 26, 27). As a result, the amount of aluminum in stratospheric sulfuric acid particles is expected to become comparable to or even exceed the amount of meteoric iron, with unknown consequences for inclusions and ice nucleation.