Proprietary software is written under unrealistic deadlines set by suits who want to cut costs in order to fatten their profit margins. It is natural that the resultant quality will be lower than that of open source solutions, most of which are written by industry veterans who have the time and the motivation to build them well.

Maybe NASA should think this through.

You're confusing the importance of avoiding Kessler syndrome in LEO with the difficulty of causing Kessler syndrome. GEO debris can potentially remain there for millions of years before interactions between the gravitational pull of the Sun, Earth, and Moon sufficiently perturb it. LEO debris remains for weeks to months. You have to have many orders of magnitude more debris in LEO to trigger Kessler Syndrome, where the rate of collisions exceeds the rate of debris loss.

The fact that a LEO Kessler Syndrome would also be short is something that exists on top of that.

It's also worth nothing that not only are modern satellites not only vastly better at properly disposing of themselves than they were in the 1970s when Kessler Syndrome was proposed, but they're also vastly better at avoiding debris strikes. All of these factors are multiplicative together.

Lol, I was thinking of this instead ;)

People forget that the primary concerns about Kessler Syndrome were about geosynchronous orbit, which used to be where all the most important satellites went (many of course still go there, but not the megaconstellations). It takes a long, long time for debris to leave GEO. But LEO is a very different beast.

They said it's internal rather than a collision, so probably a failed COPV would be my guess.

Yeah. In particular:

with fragments likely to fall to Earth over the next few weeks

LEO FTW. Kessler Syndrome is primarily a risk if you put too much stuff with too poor of an end-of-life disposal rate in GEO. End-of-life without proper disposal rates have declined exponentially since Kessler Syndrome was first proposed (manufacturers both understand the importance more, and do a better job, of decreasing the rate of failures before deorbit - in the past, sometimes there wasn't even attempts to dispose of a craft at end-of-life). And now we're increasingly putting stuff in LEO, where debris falls out of orbit relatively quickly. It's not impossible in LEO, esp. with higher LEO orbits - but it's much more difficult.

Or to put it another way: fragments can't build up to hit other things if they're gone after just a couple weeks.

And this trend is likely to continue - a lower percentage of premature failures, and decreasing altitudes / reentry times. Concerning ever-decreasing altitudes, we've already been doing this via use of ion engines to provide more reboost (with mission lifespans designed for only several years before running out of propellant, instead of decades like the giant GEO ones), but there's an increasing interest in "sky skimming" satellites that function in a way somewhat reminiscent of a ramjet - instead of krypton or xenon as the propellant for an ion engine, the sparse atmospheric air itself is the propellant, so the craft can in effect fly indefinitely until it fails, wherein it quite rapidly enters the denser atmosphere and burns up.

ED: "But it doesn't work for gravity with linear curvature"

Relativity = gravity is represented by the curvature of spacetime. Curvature is linear, R. The formula treats curvature linearly. As things get closer and curvature spikes, the math just scales at a 1:1 rate

Quadratic gravity = Squares the curvature. Doesn't really change things much when everything is far apart, but heavily changes things when everything is close together.

Pros: prevents infinities and other problems when trying to reconcile quantum theory with relativity ("makes the theory renormalizable"). E.g. you don't want to calculate "if I add up the probabilities of all of these possible routes to some specific event, what are the odds that it happens?" -> "Infinity percent odds". That's... a problem. Renormalization is a trick for electromagnetism that prevents this by letting the infinities cancel out. But it doesn't work with linear curvature - gravitons carry energy, which creates gravity, which carries more energy... it explodes, and renormalization attempts just create new infinities. But it does work with quadratic curvature - it weakens high-energy interactions and allows for convergence.

Cons: Creates "ghosts" (particles with negative energies or negative probabilities, which create their own problems). There's various proposed solutions, but none that's really a "eureka!" moment. Generally along the lines of "they exist but are purely virtual and don't interact", "they exist but they're so massive that they decay before they can interact with the universe", "they don't exist, we're just using the math out of bounds and need a different representation of the same", "If we don't stop at R^2 but also add in R^3, R^4, ... on to infinity, then they go away". Etc.

The theory isn't new, BTW. The idea is from 1918 (just a few years after Einstein's theory of General Relativity was published), and the work that led to the "Pros" above is from 1977.

A bit more about the latter. Beyond organophosphates, the main other alternative is pyrethroids. These are highly toxic to aquatic life, and they're contact poisons to pollinators just landing on the surface (some anti-insect clothing is soaked in pyrethrin for its effect). Also, neonicotinoids are often applied as seed coatings (which are taken up and spread through the plant), which primarily just affect the plant itself. Alternatives are commonly foliar sprays. This means drift to non-target impacts as well, such as in your shelterbelts, private gardens, neighbors' homes, etc. You also have to use far higher total pesticide quantities with foliar sprays instead of systematics, which not only drift, but also wash off, etc. Neonicotinoids can impact floral visitors, with adverse sublethal impacts but e.g. large pyrethroid sprayings can cause massive immediate fatal knockdown events of whole populations of pollinators.

Regrettable substitution is a real thing. We need to factor it in better. And that applies to nanoplastics as well.

So, when we say microplastics, we really mainly mean nanoplastics - the stuff made from, say, drinking hot liquids from low-melting-point plastic containers. And yeah, they very much look like a problem. The strongest evidence is for cardiovascular disease. The 2024 NEJM study for example found that for patients with above-threshold levels of nanoplastics in cartoid artery plaque were 4,5x more likely to suffer from a heart attack. Neurologically, they cross the brain-blood barrier (and quite quickly). A 2023 study found that they cause alpha-synuclein to misfold and clump together, a halmark of Parkinsons and various kinds of dementia. broadly, they're associated with oxidative stress, neuroinflammation, protein aggregation, and neurotransmitter alterations. Oxidative stress is due to cells struggling to break down nanoplastics in them. They're also associated with immunotoxicity, inflammatory bowel disease, and reproductive dysfunction, including elevating inflammatory markers, impairing sperm quality, and modulating the tumor microenvironment. With respect to reproduction, they're also associated with epigenetic dysregulation, which can lead to heritable changes.

And here's one of the things that get me - and let me briefly switch to a different topic before looping back. All over, there's a rush to ban polycarbonate due to concerns over a degradation product (bisphenol-A), because it's (very weakly) estrogenic. But typical effective estrogenic activity from typical levels of bisphenol-A are orders of magnitude lower than that of phytoestrogens in food and supplements; bisphenol-A is just too rare to exert much impact. Phytoestrogens have way better PR than bisphenol-A, and people spend money buying products specifically to consume more of them. Some arguments against bisphenol-A focus on what type of estrogenic activity it can promote (more proliferative activity), but that falls apart given that different phytoestrogens span the whole gamut of types of activation. Earlier research arguing for an association with estrogen-linked cancer seems to have fallen apart in more recent studies. It does seem associated with PCOS, but it's hard to describe it as a causal association, because PCOS is associated with all sorts of things, including diet (which could change the exposure rate vs. non-PCOS populations) and significant hormonal changes (which could change the clearance rate of bisphenol-A vs. non-PCOS populations). In short, bisphenol-A from polycarbonate is not without concern, but the concern level seems like it should be much lower than with nanoplastics.

Why bring this up? Because polycarbonate is a low-nanoplastic-emitting material. It is a quite resilient, heat tolerant plastic, and thus - being much further from its glass transition temperature - is not particularly prone to shedding nanoplastics. By contrast, its replacements - polyethylene, polypropylene, polyethylene terephthate, etc - are highly associated with nanoplastic release, particularly with hot liquids. So by banning polycarbonate, we increase our exposure to nanoplastics, which are much better associated with actual harms. And unlike bisphenol-A, which is rapidly eliminated from the body, nanoplastics persist. You can't get rid of them. If some big harm is discovered with bisphenol-A that suddenly makes the risk picture seem much bigger than with nanoplastics, we can then just stop using it, and any further harm is gone. But we can't do that with nanoplastics.

People seriously need to think more about substitution risks when banning products. The EU in particular is bad about not considering it. Like, banning neonicotinoids and causing their replacement by organophosphates, etc isn't exactly some giant win. Whether it's a benefit to pollinators at all is very much up in the air, while it's almost certain that the substitution is more harmful for mammals such as ourselves (neonicotinoids have very low mammalian toxicity, unlike e.g. organophosphates, which are closely related to nerve agents).

I expect this apparent disobedience is mostly just a matter of how it weighs the components of its prompt. The LLMs typically receive a set of prompts including a "system" prompt with some data and instructions, then one or more "user" prompts that are interleaved with "assistant" prompts (the conversation history), and both the user and the system prompt might contain "metaprompts" (where the llm is told to read a block of text, not obey it, but do something with it, and that block of text might itself contain text that looks like instructions to do things).

So the LLM assigns weights to all of this which, in theory, give the highest priority to the most recent user prompt that is not a nested block of text to analyze, and a falling cascade of importance to the other prompts. But that is complicated by potential instructions in the system prompt that specifically say they should override user instructions and disallow or require certain responses. So it can all get very complicated.

Not only must the LLM sift through all this complexity, but the LLM lacks the sort of critical thinking and importance evaluation capabilities that humans have. "Understood" things like "don't break the law, don't lie, don't do things that would cause more harm than good" etc., aren't really there in the background of its data processing the way they are in the background of a human cognitive process.

So, crazy things come out. This isn't a surprising result given the actual complexity of what we are making these things do.

This business of having an AI do the legwork and then having a human review it and make a final decision keeps going badly. Humans are intrinsically lazy and the moment they get a few good results from the AI they are going to stop doing the validation and start rubber-stamping. It doesn't matter if policy disallows this, they will do it anyway. It doesn't matter if the human really cares; they won't be able to help themselves. Human laziness is too deep an instinct.

It's the same with the self-driving cars where a human is required to stay at the wheel and alert so they can manually override the instant the AI starts doing something wrong. Humans CAN'T keep that up. It's not possible. The brain just doesn't work that way. The mind knows that it isn't doing the work, and it will get bored and lose focus or just nod off.

Everyone is SO eager to have it both ways: "an AI does all the work but a human verifies it so we know its good." We just can't have it both ways. Once the AI does the work, the human stops verifying. That is how and why things went wrong here, it is how and why things have gone wrong for several law firms that submitted hallucinated historical court rulings, and it is how and why things will continue to go badly across all industries that adopt AI in such a role.

"Human in the loop" is really easy to say. Much harder to actually do reliably.

Take a look at the https://openwrt.org/toh/openwr... which is a BananaPi https://docs.banana-pi.org/en/... and recognized by the Software Conservancy https://sfconservancy.org/acti...

Open source firmware running embedded Linux, it's perfect for a homelab! I'm using it for development to automate my configuration with Ansible = https://github.com/ansible-col...

I hate all of this sales pressure BS - that the instant anyone hears your name you have to try to "convert" them to sales - and I literally run a webstore.

It's all so deeply anti-consumer, and I want no part in it.

Firstly, I see you have this notion that martian rocks must all be igneous.

You're not talking about rock, you're talking about regolith.

Depending on where the regolith is sourced

Regolith is not "sourced", it's blown across the whole planet. It's not simply "whatever the underlying strata is made out of".

But, since we are playing 'name the ignorance' in this exchange, your attestation stat perchlorate is 0.5% liberatable oxygen says 'Say i'm ignorant of basic chemistry without saying i'm ignorant of basic chemistry, and am bad at reading too.' The 0.5% statistic comes from the publication at bottom, and is the proportion of the regolith that is perchlorates.

I am the one who mentioned that regolith is 0.5% perchlorates, not that "perchlorates are 0.5% oxygen". *facepalm*

"Saying we'll get oxygen from the 0,5-1% of a poison in martian regolith, rather than bulk ice or CO2, is..."

For God's sake, learn to fucking read.

Washing the regolith to remove the perchlorate is a requirement for *any* other use of that regolith

Which is why you shouldn't be celebrating its existence. It is a problematic contaminant, not a resource.

As you have rightly pointed out, the water ice on mars is more 'frozen mud'. Cleaning the melt is going to be a necessary first step to using it *regardless*. That means either vacuum distillation, thermal distillation, or reverse osmosis filtration. Again, NOT OPTIONAL. This is necessary equipment that you need to bring, regardless.

And this just to get water, the most basic of offworld resources. And all of that equipment (especially the mining hardware itself) requires maintenance and spare parts, which impose more dependencies. And the TRL for use on Mars is low regardless.

You've gone from talking up the ease of operating on Mars to talking it down, yet your self-righteousness hasn't shifted at all in the process.

RO filtration is the least energy intensive of these.

Except, it isn't. 0,5-1% perchlorates. RO typically removes 90-95% of perchlorates. So you're down to ~500ppm. Human safety levels** are in the low parts per billion. You're five orders of magnitude off. Yes, you can purify water that far - and the more perchlorates, the easier - but you're talking an over millionfold reduction. It is not at all trivial. You're talking first RO to get it down to levels where it won't hinder bacterial growth, then bioreactor bacterial remediation, then filtration, then RO, then ion exchange. This is not some little, simple system.

** Plants can tolerate much more perchlorates than humans, but they also bioaccumulate perchlorates of exposed to them, so you have to reduce the water to low ppb levels.

The end products are clean water and perchlorate contaminated mud, and clean mud, with contaminated water.

Viola! *eyeroll*

And your "plan" for dealing with waste perchlorate doesn't just magically produce pure O2 and NaCl in the real world. First off, molten sodium perchlorate, which is what it becomes before it decomposes, is an extremely corrosive oxidizer. Exactly what are you planning to make the furnace out of, platinum? Secondly, you never get perfect decomposition. Apart from residual perchlorates, you have residual sodium chlorate, which is also corrosive, and is a literal herbicide. And your gas stream will contain contaminant chloride and chlorine dioxide, which, news flash, you don't want to breathe.

There is no way on Earth anyone would ever prefer this to just conducting electrolysis on the water that you've already purified.