Brad RosenheimAlmost 4 #StarLink satellites fall back to Earth every day and they rain out aluminum oxide into the stratosphere which destroys the ozone layer. These satellites are more and more problematic with every article I read. Edit: corrected microsatellites to satellites per @sundogplanets 's correction that these are larger satellites than microsatellites.
Here are the original scientific papers about the subject if anyone is interested (may be paywalled):
Sources:
https://www.pnas.org/doi/10.1073/pnas.2313374120
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109280
Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ@chris Evidently there were 120 in January!
Prof. Sam Lawler@Brad_Rosenheim @chris At peak operation (assuming 42,000 sats with 5 year lifetimes), they'll be burning up 23 a day, on average.
But don't worry guys, space isn't actually an environment, so spacecraft can have a categorical exemption from any kind of environmental oversight.
@Brad_Rosenheim @chris (Sorry for the sarcasm. Long day, and I've been yelling about this to anyone who will listen for a long time).
More info here: https://pirg.org/edfund/articles/are-satellites-bad-for-the-environment/
@Brad_Rosenheim @chris Oh ALSO, these are not microsatellites. The V2 starlink satellites are the size and mass of a basic Ford F150.
A conservative estimate is 25x more aluminum from Starlink reentries than from natural meteorites. And Starlink isn't the only planned megaconstellation.
We can't have tens of thousands of throwaway satellites in orbit. It's just stupid.
nothingiseasy@sundogplanets @Brad_Rosenheim @chris A Kessler Syndrome event should reduce the size of those V2 satellites to a more manageable size.
C.@sundogplanets @Brad_Rosenheim @chris
They aren't the mass of a pickup truck. The gen 2 minis are 740kg, about half the weight of a very small modern car like a Mazda 3 hatchback. Even the full gen 2 satellites, which will need Starship to launch, are only 1,250 kg, still only 2/3 the mass of an F150.
@sundogplanets @Brad_Rosenheim @chris
Hm. And now I find another reference that says that 740 kg figure was for the initial lot of v2 minis, and that newer ones are only 525 kg. Given the rapid iteration, that doesn't seem unreasonable.
(No, I'm not defending Musk or Starlink or whatever. I just think the criticism should use the actual numbers, not attention-grabbing but inaccurate claims like "more massive than an F150". Musk is a turd.)
@cazabon @Brad_Rosenheim @chris Yeah, good luck finding consistent numbers. SpaceX documentation is nearly nonexistent. That's why I stick with quick comparisons, because I'll never get it right if I try to have an exact weight - they keep changing it (and who knows what they actually end up launching). Sorry it offends you.
@sundogplanets @Brad_Rosenheim @chris
I didn't say, or imply, that I was offended. I said that I thought criticisms should use actual numbers from reality, rather than made-up ones, which seems uncontroversial from a science-y point of view.
Being wrong by 10% because SpaceX keeps iterating the design and the mass keeps changing is completely understandable. But saying "weighs as much as an F150" when that is actually off by a factor of 2 or more - possibly closer to 4 - is disingenuous at best.
your auntifa liza ๐ต๐ท ๐ฆ ๐ฆฆdonโt be a reply guy.
author_is_ShrikeTron๐ ๐x7@cazabon @sundogplanets @Brad_Rosenheim @chris And there's no full-size v2 up there yet.
Sounds like they're retiring the early v1s probably to make room for new v2s whenever Starship starts delivering.
That they're deorbiting now signals SpaceX is thinking they're close.
Morten@sundogplanets @Brad_Rosenheim @chris But satellites burn up while orbiting and meteorites burn up while heading straight down. The "ashes" should be heading in the same direction at a similar velocity. So wouldn't it take way longer for the burn products of a satellite to leave the atmosphere than a natural bit of space debris?
@sundogplanets @Brad_Rosenheim @chris I can also see that the there are some aluminium oxide nanoparticles with special infrared properties, but I think there might be nanoparticles for every combination of material and property. I can't find anything on whether/how metal oxides disperse infrared light. It probably exists though.
Bรฅrd H. (lvl 49 ๐ณ๐ด)@sundogplanets @Brad_Rosenheim @chris
I know this sounds like "communism", but...
Over in Sweden they have a concept for providing fiber to anyone who wants it, no matter where they live
In short; One company operate the fiber infrastructure. Then any isp can provide internet access via that same infrastructure
There is no point in several companies rolling out more fiber when they can use the one that's already there
Same goes for mobile phones and electricity
So why not for satellites?
(Sorry... English aint my first language. Please explain)
Kevin Boyd (he/him) ๐จ๐ฆ@sundogplanets @Brad_Rosenheim @chris I think it was proven recently that satellites could be made of wood. Starlink should try it.
Dagnabbit, Pascaline! ๐ฅ@sundogplanets
Sarcasm is appreciated here ๐
Flatbush Gardener ๐@pascaline @sundogplanets @Brad_Rosenheim @chris
The language of my peoples.
@sundogplanets
I knew you would shed additional light here. Thanks ๐
And yes, it is deplorable. So many still have no idea that these things eventually fall back and even fewer have an idea about the consequences ๐
@sundogplanets @Brad_Rosenheim they would not be the first to be have fallen out of the environment! Lucky!
๐ ๐
https://youtu.be/3m5qxZm_JqM?si=QUeH41f297IsW_s-
๐ ๐
https://youtu.be/3m5qxZm_JqM?si=QUeH41f297IsW_s-
Clarke and Dawe - The Front Fell Off
Except ... when this claim (not about the satellites re-entering, just the amount of damage they cause to the atmosphere) started circulating some months back, I read an article (somewhere...) that analyzed the amount and type of matter it would distribute, and it pales in comparison to the amount the earth receives in "space dust" and micrometeroids every day.
Best figure I know of for the mass of "normal" space matter hitting our planet is 5,200 tonnes / year:
https://www.scientificamerican.com/article/antarctic-study-shows-how-much-space-dust-hits-earth-every-year/
The current Starlink satellites are "gen2 mini", and are 740 kg. So you would need to de-orbit more than 7,000 of them every year - not 4 per day - to even match the natural space dust falling on earth. Except it's even worse (for the argument) than that, because 740kg is their launch mass, including all their maneuvering fuel/gasses, which by definition are gone before the satellites are deorbited. I don't have an exact figure for how much mass the fuel accounts for, but it wouldn't surprise me if it was more than 25% of the mass of the spacecraft at launch.
The residue left in the atmosphere doesn't seem to be a very big deal.
#science #mass #satellite #deorbit #RunTheNumbers #calculation
edit: typo
@cazabon That is probably a bit oversimplified, but I appreciate the context of mass. Not all mass is equal. The space dust you speak of likely has a chondritic composition, rich in iron and silicates and similar to the primordial composition of the universe. Beryllium and lighter elements are probably nit significant portions of that mass of space dust because they are more volatile.
The satellites, on the other hand, represent a concentration of elements which are useful for communications and light enough for launch. The bulk composition of all those satellites is likely quite different, and enriched in rare Earth elements and volatiles like beryllium.
So the danger, then, is not the mass. It is the composition, or the mass of the harmful elements. In this case, the articles linked point out the harmful effects of these elements on the ozone layer, which protects life on Earth from UV radiation. Space dust doesn't have that negative effect.
I'm not so sure. The space dust we get isn't all one type of meteorite; it's essentially all the different types that are out there, so the composition as a whole tends towards the composition of the solid parts of the solar system. For example, it's easy to find metallic micrometeorites in your rain gutters, and they're not all just iron. Copper, aluminum, etc, etc.
I don't know exactly how much beryllium a Starlink satellite contains. I didn't think it was pure anyways - it would be as part of a beryllium-copper alloy? So the amount of beryllium entering our atmosphere from satellites may or may not equal the amount in space dust. I haven't found a study on this, everything I see said on this subject online seems to be speculation. Speculation is not a great basis for evaluating danger.
@cazabon Chondritic composition is not only iron. It is the base composition of the universe since formation, as analyzed in chondritic meteorites. The composition of the chondrite is well known and serves as a basis for evaluating other younger meteorites, like Martian meteorites from impact on the Red Planet. Beryllium is present in the chondritic composition, but at exceedingly low amounts.
Rest assured that, in the same mass of space dust and Musk satellite, the satellite has more beryllium and likely more aluminum. We cannot make satellites out of bulk Earth or chondritic composition; that is the whole point of mining.
These reports are based on two peer-reviewed scientific studies, one in Proceedings of the National Academy of Science, and the other in Geophysical Research Letters. The first study uses the number 10% aluminum, which is much more enriched than the chondritic composition. The studies don't mention beryllium; that was brought up as a concern by someone responding to my original post. The mass and the altitude interplay to directly inject more of this aluminum oxide to the stratosphere directly, whereas lighter dust particles generally do not burn up or melt, and they make it to the surface of the Earth. In the second link, the authors calculate a 29.5% increase in aluminum over natural levels, which would include space dust.
I hope that helps allay your concerns about speculation.
Sources:
https://www.pnas.org/doi/10.1073/pnas.2313374120
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GL109280
anlomedadThe natural amount of "space stuff precipitation" does not destroy the ozone layer [anymore].
Add more, and the story changes.
And with an orbital life of 5 years for the target of 40k simultaneous satellites, Starlink would be trashing 8k sats per year. This would more than double the natural amount - if those 7k that Cazabon mentioned are correct.
Today, those 120 sats burning up in January alone, got shot up there in 2019.
Wait till 2023 rains down.
Or don't. Wait, I mean. Don't wait. But instead regulate Starlink out of business immediately.
Jรถrg Seidel@Brad_Rosenheim
that number will increase to about 20
@Josteglitz
Fiona Bianchi@Brad_Rosenheim the whole reliance on satellites ๐ฐ๏ธ reminds me of two films: Independence Day and Wall-E. I suspect the scenes from the latter are starting to become realistic. The problems of the former are maybe not so immediate but I do think relying so much on radio/microwave comms seems bad engineering.
John Carlsen ๐บ๐ธ๐ณ๐ฑ๐ช๐บ@Brad_Rosenheim thanks for sharing.
May I add: holy shit, Musk is destroying our planet!
Translated from Italian:
"Musk, 7 thousand Starlink satellites ready for re-entry: but they pollute the atmosphere with metals and aluminum oxide. In January 120 devices on the ground
Scientific studies demonstrate the threat to the environment of Starlink devices: they produce 30 kilograms of aluminum oxide. The concentration of this substance in the air increased 8 times between 2016 and 2022"
by FQ
February 7, 2025
Musk, 7 mila satelliti Starlink pronti al rientro: ma inquinano lโatmosfera con metalli e ossidoโฆ
Studi scientifici dimostrano la minaccia per l'ambiente dei dispositivi starlink: producono 30 chilogrammi di ossido di alluminio. La concentrazione di questa sostanza nellโaria รจ aumentata di 8 volte tra il 2016 e il 2022
Paul Wermer, CC BY-NC-SA 4.0Prima facie support that #NEPA and related #EnvironmentalProtection strategies worldwide are totally inadequate to address emerging technology threats, esp in a world of #billionaires and #MultinationalMegacorporations.
@PaulWermer
Interesting. It does seem futile, especially when I speak to those who enjoy technological advances more than the environment. Many have "drunk the Kool-aid" of these megacorporations.
And #SCOTUS with its wastewater ruling today has signaled that they'll reverse any rule that allows these emerging threats to be addressed in a meaningful manner. They will insist on highly prescriptive rules.
Why is it that conservatives are so opposed to conserving a safe and (reasonably) stable environment?
@johnlogic He is a miner, through and through. He grew up rich due to extraction, and every business he every fiddled in involves increased extraction. He cares not about the planet; he wants to scrap it for parts and move to another one.
And this message needs to reach many before his popularity, and the popularity of megalomaniacs like him continues to grow.
kdacar@johnlogic @Brad_Rosenheim Good thing we fixed the ozone hole back in the 70s when international cooperation was famously good.
@kdacar
We did not completely fix it, we set it in motion to repair itself. And it was trending positively, but not yet back to pre-CFC levels.
I miss that world where environmental doom promoted international cooperation. Now the corporations rule us all.
Edelruth, PBS Passport HolderGood call; I already follow @sundogplanets
fuzzface
Aaron Williamson@johnlogic @Brad_Rosenheim actual chemtrails, brought to you by the party put in power by the People Against Chemtrails.
Patryk 
yeah, and they're literally falling - e.g. part of the booster fell next to the highway in Poland - 200-500m of deviation and it'd literally kill someone
CC: @[email protected]
CC: @[email protected]
Licho@Brad_Rosenheim @sundogplanets are they at least seeding some clouds??
๐๐ท๐ญ๐๐ฃ๐ฒ๐ฎ๐ญ๐๐ฎ ๐คWe need an in-space recycling service.
Don't let those old dead satellites just deorbit and fall to the ground or drift endlessly presenting a navigational hazard. Collect them and use the material to make new stuff, in space!
PeaceNick๐จ๐ฆ@andytiedye @Brad_Rosenheim @sundogplanets
Haha.
There was an old TV show circa 77-78 with Richard Benjamin called Quark.
"The show was set on a United Galaxy Sanitation Patrol Cruiser, an interstellar garbage scow operating out of United Galaxy Space Station Perma One in the year 2226. Adam Quark, the main character, works to clean up trash in space by collecting "space baggies" with his trusted and highly unusual crew."
VulcanTourist@Brad_Rosenheim @sundogplanets
It's part of the strategy to hasten the planet to a literally unlivable state so that the human race has only the option to flee elsewhere... that elsewhere being Mars. Musk will have a slave population that cannot survive without his largess.
Confusion as a Service@Brad_Rosenheim @sundogplanets Chemtrail folks: **crickets**
Visikde
Dietrich Feist@Brad_Rosenheim @sundogplanets
I do not like #ElonMusk and I believe that #Starlink's usefulness is totally outweighed by the many impacts it has on limited global resources like space in the #LEO.
However, it is currently not clear whether the current levels of aluminum oxides from reentering satellites could pose a threat to the ozone layer. Even though the amount of Al in stratospheric aerosols (of which we have only limited samples) has been increasing, the total mass of anthropogenic Al oxides is still orders of magnitude smaller than the natural injection of metal oxides from meteorites - which itself is small compared to stratospheric aerosol injection from volcanoes.
Also, it is quite likely that most of the anthropogenic Al in the stratosphere is actually emitted from solid rocket motors (SRM) and not satellites upon reentry.
There was a paper in #GRL last year that tried to sum up what we know. As an atmospheric scientist, I do not agree with all their conclusions but it is still worth reading.
MikPetter@dgfeist @Brad_Rosenheim @sundogplanets @mikpetter I was interested in the SRM contributions and found this other paper that talks about their short term ?? contributions extract from the paper https://doi.org/10.1073/pnas.2313374120 โ.. A detail in the correlations of copper and lithium with aluminum points to a possible small contribution from rocket exhaust. The correlations in Fig. 3 are linear except at the very highest Al/Fe ratios. Examination of such single-particle mass spectra shows that a few are similar to alumina particles emitted by solid propellant rocket motors (15). The vast majority of the mass of alumina particles from solid rocket motor exhaust is contained in a >1 ยตm mode that quickly sediments from the stratosphere. A lesser submicron mode (16) could remain in the stratosphere with subsequent condensation of sulfuric acidโฆโ
@dgfeist
Does particle size matter? The vast majority of meteoritic debris is micrometeorites and dust, a lot of which does not burn up in the atmosphere. These satellites at least partially burn up while in the upper atmosphere. But my knowledge of space debris, oddly enough, comes from marine sediments.