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Comment Google Pixel (Score 1) 107

Time to pick up a used Google Pixel and replace the OS with something open source. I only target the Pixel because there are more compatible open source OSes than on other systems, at least as far as I know. Do people think they (deliberately vague) could get away with ultimately requiring that the phone OS be certified to have implemented Age Verification(tm), and mandate that the carriers not interact with systems that are not running a certified system?

Comment No Useful Information (Score 5, Insightful) 90

There's no real useful information to be had in the article. The fact that Apple provided the associated account information means nothing. The only useful fact to know was whether they provided that information in response to a simple request or was a legal document presented that required them to provide the details and that's not covered.

Comment Re:It will flop (Score 1) 26

Something like this needs density. If there's not enough people using it, then the per use cost will be far too much to make it economically viable. That makes cities much more attractive to startups like this. Of course there you have airspace issues with large buildings, so the true sweet spot may be relatively dense but very high income suburbs. But it sure as heck won't be rural.

Comment Re: Potential dangers (Score 1) 92

Rei, it's always this way with you. Take the chip off your shoulder.

Firstly, I see you have this notion that martian rocks must all be igneous. This is not correct. That planet has had extensive geologic hydrolysis. Noteworthy shale formations have been found at Jezero and Gale.

https://news.mit.edu/2024/stud...

https://agupubs.onlinelibrary....

The generalized composition profile for windblown dust is very high in basaltic minerals, but many noteworthy sedimentary-dominated structures have been catalogued, as above. Depending on where the regolith is sourced, its composition can vary widely. Blanket statements like 'regolith is not shale!', does not engender notions of superior knowledge. Regolith is the fine to midsized mixture of fractured rocks on the surface. Its composition will be determined by wind erosion and transport patterns, and which rocks became wind eroded. As pointed out above, large surface deposits of hydrolized mineral layers are present on mars.

Rather than pretend I dont know this, I instead correctly asserted that what you do with the collected dust after extracting the perclorate depends entirely on its composition, which will be very site-specific. The one making silly generalizations about the regolith is yourself, Rei.

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. This is one of those lemons you seem to have a hard time with, so I'll hold your agitated little hand on this one.

Washing the regolith to remove the perchlorate is a requirement for *any* other use of that regolith. The chlorine it contains is a fouling contaminant for any other industrial process that you put it through. It's not optional. This stuff MUST be washed first. Even at this low of a concentration, its presence would destroy melting crucibles, and deleteriously affect the mechanical properties of resulting products.

Washing it is not optional. It's a required first step for any subsequent process.

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. RO filtration is the least energy intensive of these.

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

Since we already have to bring the RO equipment, do it like this:

Permafrost goes in RO unit 1.
clean water and salty mud come out.

Dry, salty regolith, and the dirty mud go in an agitation and settling system. It gets completely cleaned through agitation and settling in a continuous inflow agitator, until water testing shows clean (salt free) water at the outflow. The dirty water is partially re-added to the salty mud in the RO unit, which is processing permafrost, to improve filtration. The remainder is low-sediment saline water, which is fed to another RO unit, giving potable water, and concentrated perchlorate saline solution as products.

This gets you cleaned regolith, concentrated perchlorate brine, and fresh water.

Of those, only one is a lemon. The perchlorate brine. The other two have industrial or immediate uses.

What do we do with this nasty bitter lemon? Do we complain about it, or put it to use? You seem to favor complaining about it, but that's dumb. Instead, it should be made into lemonaide.

Now that we have strongly concentrated the stuff, as a biproduct of producing other things this doomed colony needs, I remind you, the percentage of this stuff is going to be very much higher than 0.6% by weight, so kindly shove that out the airlock, and look at what perchlorate salts *are*: highly oxygenated alkali-earth and transition metal chlorine salts, with a very high recoverable oxygen value.

The very same publication that gives the 0.6% wt value, also gives us a generalized compositional makep of what perchlorates we have. They assay it as predominantly calcium and magnesium perchlorate.

Here are the percentages of oxygen (many wholly liberatable) by weight of various anhydrous perchlorate salts, including calcium and magnesium), and the thermal decomposition temperatures of each. (No electrolysis, just getting it hot enough. Though again, if we have nitrogen, we can use bioreactors for this very cheaply instead. Since thats not guaranteed, here's the thermal decomp route.)

Sodium Perchlorate (NaClO4): 52.3% liberatable oxygen by weight. Thermal decomp at 490-520C at 1atm.

Potassium perchlorate (KClO4): 46.19% liberatable oxygen by weight. Thermal decomp at 550-600C at 1atm.

Calcium perchlorate (Ca(ClO4)2): 53.56% liberatable oxygen by weight. Partial decomp at 150C(!), full decomp at 380-570C at 1atm.

Magnesium perchlorate (Mg(ClO4)2): 57.3% liberatable oxygen by weight (but requires more processing to get it all). Thermal decomp (to MgO) at 369-429C.

Aluminium perchlorate: (Al(ClO4)3): 58.9% oxygen by weight. Aluminium holds oxygen very tightly. Decomposition produces a mix of oxygen and chlorine gasses, with pure aluminium oxide as the end product. This is a useful substance, as it's a principle ore of aluminium, and a useful abrasive in manufacturing. Thermal decomposition begins at 150C, and ends at 450C. (But unlikely to be a major constituent of martian regolith)

Iron(II) perchlorate (Fe(ClO4)2): 50.24% oxygen by weight. Like Aluminium, it holds oxygen tightly. The decomposition initiates a redox reaction that turns iron(ii) into iron(iii), resulting in iron(iii) oxide (Fe2O3), and a mixture of oxygen and chlorine gasses. It functions as a catalyst in the thermal decomposition of other perchlorates. Decomposition starts at 100C(!)

Iron(iii) perchlorate (Fe(ClO4)3): 54.2% liberatable oxygen by weight. Basically the same as iron(ii), but is already oxidized to iron(iii).

Since we need to heat the now cleaned regolith to its melting point *ANYWAY*, (in order to get glasses, basalt fibre, or bisqued shales, as appropriate) we can use the same industrial plant to thermally decompose the perchlorates. If we're building sintering furnaces, we are building sintering furnaces. The decomp temps are comparatively low, compared to the temps needed for melting bassalt. The melting / bisqueing of the regolith will also evolve useful gasses we want to collect and refine later, because of local scarcities *anyway*, so having the equipment in one processing plant makes logistical sense.

Our outputs here are alkali earth oxides (mainly calcium and magnesium oxides, which are useful for making concrete) and chlorides (which are useful for an abundance of chemical processes), oxygen, chlorine, and water vapors, and industrial regolith end products (glasses, basalt fibre, or bisqued shale pellets or bricks, depending on what we fed in.)

Fractional distillation of the gasses will give you distilled water, liquefied oxygen gas, and compressed chlorine gas.

Noteworthy publications:

https://pmc.ncbi.nlm.nih.gov/a...

Comment Re: Potential dangers (Score 1) 92

I am not interested in an an argumentative tit for tat Rei.

Perchlorates can be broken down through bacterial processes in water (but assumes you have the other things you need for life, which we dont here. Then again, I am open to nitrogen sources existing, but being undocumented. If they do, this by far the least expensive means), and through electrolysis with a boron doped diamond electrode set.

Which just so happens that this latter is also be your preferred method, since it breaks the water as well. The increased ion content of the water would increase bulk oxygen yeild over pure water.

Why are you complaining, instead of being informative?

As for mineral dusts being bad, it depends on how hygroscopic the dust is. Shales and clays are indeed bad (but can be sintered into bisque that is not). Fine silicon oxide species less so (but are better used to make glass). Sintered bb sized balls, being much more ideal.

Again, why be argumentative instead of informative?

The statement about bassalt fiber is not meant to be taken in a horticultural context. It's vastly more useful as a construction matetial for high pressure vessels, which any 'earth atmospheric pressure' cabin WOULD BE, compared the the outside pressure. Not all regolith compositions produce bassalt fibre when melted though, which is why there is the caveat. Even the powders not useful for either role (like calciferous minerals) have industrial uses as bulk fillers for plastic resins, and as cement.

  It's almost as if you are either unwilling or unable to 'make lemonaide' from the lemons, because you are used to using only abundant fresh fruit.

The notion that only perfectly ideal conditions or materials are required, rather than just preferred, is not consistent with reality.

A more honest appraisal looks at the costs associated with using what's actually available, and if they exceed operational thresholds or not. 'Is it cheaper than importing from Earth', and 'Can we actually systain the infrastructure required on-site' being the important questions. NOT 'can we compete with people in the market who have ideal feedstocks'.

People have made housing from regional materials for thousands of years. The kinds of conditions that forced that are present on both the moon, and Mars. Think of ways to make lemonaide, and less about how you dont have fresh guava juice.

Comment Re: Potential dangers (Score 2) 92

I'm not so sure that perchlorates are such an awful sticking point.

(This is not meant to be a post in support of this study, mind. Please do not infer that it is.)

Perchlorates are a 'potentially useful' chemical salt, that form from slow dehydration and UV exposure in an oxygen rich envirionment. They contain a lot of chemically bound oxygen, that is relatively easy to liberate, producing reactive oxygen species when that happens.

Numerous findings of water ice have been made on Mars, which means it can be collected from the Martian envirionment. The primary ways perchlorates decompose is from exposure to water and heat. Perchlorates are also generally water soluble, which is one of the reasons they are harmful to human health.

Together, this suggests Martian regolith that is loaded with perchlorate is a potentially valuable source of easily extracted mineral-derived oxygen gas, which would be essential for a manned Martian colony mission. The extraction of this gas from the perchlorates would leave alkali-earth chloride salts behind in the reactor vessel, but these have other industrial uses, such as the production of hydrochloric acid, and the production of vinyl-chlorides.

Extraction of the perchlorates from the regolith through this industrial process would produce an abundance of potentially useful mineral dust to use hydroponically, or, if the composition is useful and fit for purpose, as raw material for sintered brick and basalt fiber.

The elements in low abundance are nitrogen and phosphorus. These are the real sticking points, from my understanding. The only sources of these would be from radiological processes, or from importation from earth. Both represent a very significant scarcity that would make the idea of 'colonization' infeasible.

Lunar regolith spectrometer data suggests that lunar soil does contain phosphorus, but in very low concentrations. Carbon and nitrogen are scarce.

The majority of publications about Martian regolith is about geochemical evidence of hydrolysis and water-erosion evidence, and talk about perchlorate levels. I have not seen good datasets detailing phosphate levels, or nitrogen sources. They may exist, but I have not seen it discussed much.

Comment Jeez, not this shit again (Score 2) 160

.... most Americans say they would prefer to make daylight saving time permanent

Yes, they say that, until you actually do it. Then ...

.... an unpopular, brief stint in 1974

50+ years ago we went on permanent DST, and it lasted less than a year. When winter came, people didn't like that their kids had to go to school in the dark (among other things).

Here are your available options:
(a) Change the tilt of the earth so that we always get the same amount of daylight year-round
(b) STFU

Comment Re:it's getting better and better (Score 1) 101

Except it really isn't. The stuff from 2 years ago is miles ahead from the stuff 5 years ago. The stuff from 1 years ago is yards ahead of 1 year ago. The stuff from 6 months ago is nearly indistinguishable from the stuff from a year ago. Diminishing returns is hitting hard and rapidly. Many experts think that LLMs are closing in on their technical limitations, regardless of how much extra compute its given. It will need entirely new techniques to actually become much more than it is now. Which may happen, but doesn't appear to be on the horizon.

Comment Re:LOC written as a performance metric? (Score 1) 101

A study you can't even directly link to? Yeah, I call bullshit.

And my personal experience is it's at least a 50% slow down. I have yet to ever have it do anything not completely trivial that wasn't badly insecure and broken, and when using them to provide static analysis the false positive rate is around 90%.

Comment Re:LOC written as a performance metric? (Score 3, Informative) 101

No, those who aren't willing are actually following the science. Every measurement so far, every actual study has shown AI code generation is 20% or more slower for senior engineers. Even scaleai, a company founded and run by Meta's AI chief, shows the same in their data (https://scale.com/leaderboard/rli). Possibly it will someday get there, but it sure as hell isn't ready yet.

Comment Re:Strike Two (Score 1) 62

Still trivially though for any talented reverse engineer. Somewhere in the code they have a function that checks if they think they're 18 and returns a boolean. Change the function to always return true. It would be harder if it was sending the image up to the server to analyze, but local is easy to break.

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