What is it that the author thinks is particularly unusual about this image? Pretty much every schematic of a Teller-Ulam type weapon -- a schematic which you will find in every introductory Nuclear Physics textbook -- shows a large cylinder with a spherical fission device at the top and a cylindrical fusion device at the bottom, plus some FOGBANK-type material of unconfirmed purpose. This image looks exactly like those schematics except that someone has imagined some little channels which look like they're intended to move energy from the primary to the secondary. Without detailed simulation and testing, a prospective weapons designer has no way of knowing whether those channels are representative of a real weapon, or just a superficially plausible hallucination.
Overall this looks like someone asked a physics undergraduate to spend an hour imagining roughly how the well-known schematic might be fitted inside a real warhead case. It probably is exactly that. I can't imagine that showing it to the North Koreans advanced their nuclear programme by any more than fifteen minutes.
> What is it that the author thinks is particularly unusual about this image?
In two decades of crawling through most of the declassified public nuclear material from the US nuclear weapons program, some exposure to classified material, and numerous hours of interviews with working and retired nuclear scientists he believes it's the single most detailed schematic of an actual specific type of warhead he's seen so far.
As he's blogging about this it's almost certain he has had real current working nuclear weapons experts from his contact list read the advances and not disagree.
Correct or not, it's not a casual random thought from someone with no exposure to such diagrams.
He says it a few paragraphs in:
“To give a sense of how strange this is, here is the only “officially sanctioned” way to represent a multistage thermonuclear weapon, according to US Department of Energy guidance since the 1990s:
Figure 13.9, “Unclassified Illustration of a Staged Weapon
(Source: TCG-NAS-2, March 1997),” from the Nuclear Matters Handbook 2020 (Revised), published by Deputy Assistant Secretary of Defense for Nuclear Matters.
Two circles in a box, maybe inside of a reentry vehicle. That’s it. Nothing that gives any actual sense of size, location, materials, physicality.”
The unusual thing, as stated repeatedly throughout the article, is that this is published by people who are under one of the strictest censorship systems in the world, a system that explicitly exist to prevent the publication exactly this sort of thing.
Photos of even a hint of the inside are rare enough that he has another article show (in effect) a hint of an imprint from an old photocopying mistake.
I also doubt it's useful, but Ted Taylor could supposedly walk around a room full of nukes and guess based on the shape of the casing what was unique about a design
I feel like the most novel aspect of this image is an implication of the shape of the reflective casing at the far rear of the device--it seems to suggest a parabolic "shaped charge" sort of focusing element that likely helps to boost the neutron flux and initiate the "spark plug" from the rear at the same time as from the front.
Find the paragraph that says "so this is awfully strange" and start there. It's a detailed analysis of the graphic in question, and what's "unusual" about it is that this graphic, with the detail identified by the author, has been published at all.
The next paragraph details what the author would have expected to be published by comparison.
And then figure 13.9 is what the DoD expects to see published at all.
> What is it that the author thinks is particularly unusual about this image?
Read the article and look at the "officially sanctioned" diagram. This looks like the tl;dr of what he things about this:
> Anyway, I’m just surprised the DOE would release any image that gave really any implied graphical structure of a thermonuclear secondary, even if it is clearly schematic and meant to be only somewhat representative. It’s more than they usually allow!
> ...but we’re given a rare glimpse inside of modern thermonuclear warheads. Now, there isn’t a whole lot of information that one can make out from these images. The main bit of “data” are the roughly “peanut-shaped” warheads, which goes along with what has been discussed in the open literature for decades about how these sorts of highly-efficient warheads are designed. But the Department of Energy doesn’t like to confirm such accounts, and certainly has never before let us glimpse anything quite as provocative about these warheads. The traditional bomb silhouettes for these warheads are just the dunce-cap re-entry vehicles, not the warheads inside of them.
Low radiation steel is less needed because new steel is lower radiation. The atmospheric radiation level has dropped and steel making uses oxygen instead of air.
Presumably there are uses that need old steel but they are probably smaller amounts.
Not that the image itself is particularly useful or descriptive (it's not), but because the review office is rather quite conservative when deciding what to release, and anything suggestive of a real device is usually right out. In this case, the initial approval was probably an anomaly. I suspect that the reviewers looked at it that day and thought "eh, this is so far from reality that it's just not a big deal", and let it go. Any other day or set of reviewers and it probably would have been kicked back. It would be interesting to know the story around that approval, and what the fallout was, if any.
Any further use isn't very surprising. Once it is approved and in the wild, re-using it is not really a problem (especially if being run through the same office for approval again).
Even so, it would be very unusual if I understand the author correctly:
> ... at least historically, the Atomic Energy Commission and its successor organizations have frowned on disinformation and misinformation for other very practical reasons. If you release a lie, you run the risk of someone noticing it is a lie, which can draw more attention to the reality. And even misinformation/inaccuracy can put “brackets” around the possibilities of truth. The goal of these organizations is to leave a total blank in the areas that they don’t want people to know about, and misinformation/disinformation/inaccuracy is something other than a total blank.
In other words, the author expected to see a previously familiar schematic or nothing. This is clearly not nothing, and also not a familiar schematic, hence the surprise.
plus the us disinvolvment has driven incentives to get nukes through the roof.ukraine support is a scary casus belli if you are the neighbor of a landenpire.
Now imagine broke Pakistan auctioning off nukes to american allies in eastern europe or chinese neighbors. the maga movement has a price tag and thats that for this world order.
The article is not about warhead technology, it is actually about the internal culture of how the military and nuclear-adjacent agencies classify and communicate about nuclear technology.
But here’s the thing: that internal culture is just as opaque to outsiders as the technology itself! No outsider actually knows how the internal folks think, feel, and decide about little graphics or schematics or whatever. They’ve just inferred some heuristics from incomplete data.
And this is basically just saying “this little graphic seems to violate my heuristics.” Which makes for interesting reading, but there is no real actual objectively verifiable content in this article.
Betteridge’s Law tells us the answer to the headline question is always “no.” And in this case I think common sense agrees: Sandia Lab probably did not give the entire thermonuclear ballgame away with a logo graphic.
Please provide even one link to an image or book or anything that proves what you're saying is true. The fact that this is the top comment is troubling, since your question is answered throughout the article. The thing you're claiming (basically that imagery like this can be found all over the place) is so easy to prove, one wonders why you haven't done it here or in any of your other comments.
No. That is not a nuke. It is a mass simulator, specifically the electronic model of a mass simulator for a warhead. The various colors represent density of material. This would be used during aerodynamic simulations. That is why it is behind the graph about processors. This also explains the simple geometry as keeping things simple reduces the number of calculations.
(Note that nuke warheads fall nose-first, the opposite of space capsules. So the dense material is packed in the nose, with the lighter stuff at the back.)
The nearby disk looks like a represention of airflow around a falling warhead. They, like apollo, likely had an offset center of gravity that allowed them to stear by rotation, creating the asymetrical airflow shown on the disk. Falling in a spiral also probably frustrates interception. So that whole corner of the image is advertising Sandia's ability to do aerodynamic simulations.
You have a technical expertise just close enough to, but firewalled from the actual doe nk physics, where maybe the same image couldn't be released by anyone with doe clearance.
But the guy a few buildings over just doing 'hypothetical' center of gravity modeling? Doesn't necessarily have to live by the exact same rules or go through the same release/declass process as someone with actual weapons schematics.
It leaves a lot still unanswered- but explains away some of the seemingly self- contradictory Sandia policy discussed in the article.
In industrial speak: inside-the-fence vs outside-the-fence regulatory framework, or something similar.
Sometimes the guy outside the fence 'gets away with things' because those things are OK to do outside the fence.
Reminds me of another design secret that leaked out because someone published a paper titled something like "X-ray crystallography of Lithium Deuteride under high pressure."
People very quickly figured out that this was the source of the D-T fuel in fusion part of the bomb instead of cryogenic D-T liquid. Lithium Deuteride is nasty stuff, but it's a storable solid. When bombarded with neutrons from the fission primary, the Lithium splits and forms tritium, which then combines with the deuterium that was the other half of the crystal.
The reason the usage was obvious (from the title alone!) is that very few chemists would care about any property of Lithium Hydride, which is dangerous to handle and has few practical uses. Lithium Deuteride is unheard of in analytical chemistry, and its crystallography under high pressure is totally uninteresting to anyone... except physicists working on atomic weapons.
I've done branding and identity design in the past, and got university training to do it. I've also worked as a developer and contributed a ton to FOSS projects. That an engineering organization thinks this is a product logo is entirely unsurprising. I'll bet their interfaces are really something.
The most frustrating thing about being a designer in those environments is the dunning-krueger cockiness many technical people have in their understanding of design, which they usually believe is purely an aesthetic consideration.*
It's not even like a junior developer trying to 'correct' a senior developer about coding practices in a dev meeting— the better analog is a designer that watched a half hour Coding for Designers talk at a conference trying to correct a senior developer about coding practices in a stand-up, because they'd never have been invited to the dev meeting to begin with. If there were only designers in that meeting— and they likely find the other designer more credible because they jibe with their perspective, don't realize how important the developers input is, and might have watched that same conference talk— that could damage a project. In my experience, designers are way more likely to be solo in meetings with developers and the echo chamber of developer 'expertise' on design drowns out actual professional design expertise. In most FOSS projects, is bleaker than that because designers don't even bother trying.
* though completely out-of-context "rules" born from Tufte quotes aren't uncommon. In art school, we were told that we need to understand the rules in order to know when to break them. Imagine someone who'd never driven before that memorized a few pages of the driving manual calling you an unqualified driver because your actions didn't comply with the letter of one page they memorized even if it was qualified by another, or required for safety.
I've worked on (unrelated to nuclear stuff) computer simulation projects for the Navy where they had standard, notional models of the battleship which had the same sort of general properties you'd expect a battleship to have, but wasn't based on the design of any real battleship, so they could share them with researchers to develop their codes on without having to worry about revealing classified details.
Wonder if this isn't something similar, if the DoE has some sort of "standardized notional warhead" design they can use to give to outside researchers without having to give every post-doc and grad-student a security clearance.
The author addresses this in the addendum after the article. Something like that already exists, and it isn't this.
> MACE (Modal Analysis Correlation Exercise) assembly, and was created by the UK Atomic Weapons Research Establishment in the 1990s to serve as a sort of a Utah Teapot of weapons structural modeling: a benign shape that could be used to test aspects of the code that would nonetheless tell you if the code would work for real weapons assemblies.
Do you actually mean battleship, or frigate, corvette, aircraft carrier, etc? Battleships in the sense of the Iowa class and similar haven't been a thing in the US Navy for a very long time, unless you were working on blast damage/effect simulations in the 1980s when Reagan reactivated them for a short time.
> This is the kind of thing that I think people assume the government labs might do, but in my experience, is pretty unusual and pretty unlikely. In general, you have to remember that the national laboratories are pretty, well, boring, when it comes to classified information. They want to be boring in this respect. They are not doing cloak-and-dagger stuff on the regular. They’re scientists and engineers for the most part. These are not James Bond-wannabes.
The Sandia folks may be extra special, it is a pretty famous place. But engineers are people first of course, so lots of variation. And also, some are super serious of course, but there are hacker tendencies, playful tendencies. I bet if some intelligence agency folks wanted to, they could find some engineers out there who’d be receptive to this sort of thing.
If it is a fake, known-stupid design, including it would be a funny prank that wastes the time of people that might want to nuke us, right?
I visited Los Alamos earlier this year and talked to a retired materials scientist at the visitor center. He said that we have lots of books about the science and scientists that worked on the bomb during WWII, but very little mention of the engineering or engineers - and that's largely because it's extremely classified. The scientists can talk about most of their work because it's too broad to give any real aid to the enemy, but the engineers can't because they could REALLY speed up someone else's weapons program.
Somebody (probably a programmer or engineer) took the time to create all of that rad 3D word art, multicolored pie-chart, and the mountain logo, it's not hard to imagine they'd also throw in an eye-catching fake nuclear warhead for fun.
I bet it's an inside joke, like Lenna.jpeg. Some outdated / test / dead-end, or otherwise harmless project put there as a wink to everyone involved in the industry. Maybe it's something an intern ruined on his first day and made entire lab work on for three weeks without realizing?
I see a few commenters think the big chart/diagram in the first picture is the one being discussed. It is not, it's the rightmost slice ("Salinas") of that infographic which shows something like a warhead. It's shown blown up (pun intended) in the second picture of the article.
Basically 0 CAD models you see with color coding and a mesh are actually accurate.
In order to mesh the geometry for finite element analysis, the geometry virtually always needs to be defeatured.
So the cross sectional CAD model here is a nice curiosity but basically useless for any reverse engineering purposes which is the key reason this stuff is kept secret.
In Germany we say "The DIN knows non color". DIN is our standardization organization and informally also how their documents are called.
I did finite element model preparation for a living many year ago and it did not only involve heavy defeaturing but interestingly also remeshing with quads.
Renderers love triangles, FE solvers love boring quads.
Sandia FEM is using the different blocks (colors) to represent different materials. This is pretty common in a multi physics finite element program.
This story is probably nothing interesting because this went through all the public use approvals needed for public presentations and being available on osti.gov.
It is probably just a toy test problem used on a capabilities logo for Sierra. Maybe it comes from some sort of integration test that is easier to run than the actual problem.
I would bet a few dollars that no Facility Security Officer (the name for people who manage security programs for defense contractor, despite sounding like a Sunday name for ‘guards’) in the entire NNSA complex has ever read Arms and Influence. That’s not quite their demographic profile.
That was my first thought too. If you screw up once, and then redact it in the future it's screaming "Hey everybody look here, there's classified information"
Some people are confused why this could be a big deal. An analogy: on GitHub, if you echo a GitHub access token in an action’s log, it will be automatically censored. This post would be like noticing that someone’s action step is just named ghp_1ae27h… and that the name isn’t censored, and speculating on what that says about the token-censorship algorithm
This thing could be a test object that doesn't work as an actual nuclear warhead but is similar enough to validate the discussed software: real-world crash tests match software simulations, and being accurate at simulating the dummy is a guarantee of being accurate at simulating classified weapon designs.
> Someone reminded me of something I had seen years ago: the British nuclear program at Aldermaston, when it has published on its own computer modeling in the past, used a sort of “bomb mockup” that looks far more deliberately “fake” than this Sandia one. I offer this up as what I would think is a more “safe” approach than something that looks, even superficially, like a “real” secondary design:
> This is called the MACE (Modal Analysis Correlation Exercise) assembly, and was created by the UK Atomic Weapons Research Establishment in the 1990s to serve as a sort of a Utah Teapot of weapons structural modeling: a benign shape that could be used to test aspects of the code that would nonetheless tell you if the code would work for real weapons assemblies.
Heh. Ask my mother about the time that Sandia dropped an atomic bomb casing in the streets of Albuquerque.
IIRC the story, this was still during WWII. They were testing the flight characteristics of the bomb casing. It did not contain a core. But it was still extremely classified. They had the test casing in the back of a truck, taking it from Sandia to Kirtland AFB. The truck got in an accident, the tailgate fell open, and the bomb casing fell out and went rolling around in the street.
Let's assume the schematic depicts a genuine weapon, and that this was a massive redaction screw-up.
I think the author is omitting the most likely explanation for why it wasn't redacted in future publications.
It took from 2007 to 2024 for someone (him) to publicly notice this.
If your job was to censor documents coming out of Sandia National Laboratories, and you screwed up this massively, what's your incentive to call attention to your screw-up?
Better to just coast along, by the time you retire or move on to another job your ass is off the firing line.
Ditto (but less so) if this was your co-worker or team mate, after all North Korea, Iran etc. already have access to the published document.
What could anyone in your organization possibly gain from the ensuing shitstorm of admitting something like that?
Has this person worked, well, pretty much anywhere, where people have a stronger incentive to cover their own ass and keep out of trouble than not?
Or, that internal report and subsequent shitstorm did happen, but what do you do at that point? Make a big public fuss about it, and confirm to state actors that you accidentally published a genuine weapons design?
No, you just keep cropping that picture a bit more, eventually phase it out, and hope it's forgotten. Maybe they'll just think it's a detailed mockup of a test article. If it wasn't for that meddling blogger...
Edit: Also, I bet there's nobody involved in the day-to-day of redacting documents that's aware of what an actual weapons design looks like. That probably happens at another level of redaction.
So once something like this slips by it's just glazed over as "ah, that's a bit detailed? But I guess it was approved already, as it's already published? Moving on.".
Whereas a censor would have to know what an actual thermonuclear device looks like to think "Holy crap! Who the hell approved this?!". And even then they and the organization still need the incentive to raise a fuss about it.
My experience working for huge orgs where success and failure is many nodes removed from individual actions makes me vote for this as the most likely scenario.
It took until 2024 for the author to see the image, he noticed the screw up within moments of looking at it. Betting that no one is going to look at a logo before you change jobs is a pretty big gamble.
Updating a logo (especially a bad logo) after a couple of years is not exactly a newsworthy event. If you replaced any other part I would not assume it was to correct an accidental disclosure of classified information.
Isn't one of best ways to verify this is to computationally "detonate" a similar model? If it's real, it should compress nuclear part, if it's not, it behaves like a HEAT warhead or whatever it is based on, or is that not the case?
There is the fission stage and the fusion stage. The fission stage in this image is not well represented. It is generally known how to make a fission stage similar to the “Fat Man” device but the “Fat Man” device is larger than the whole warhead with both a fission and fusion stage that fits on a Minuteman 3.
The fission stage in that warhead has numerous refinements that help miniaturize it, for instance the implosion is probably not spherical so it can fit in the pointy end of the warhead. A really refined modern weapon is packed with details like that.
They would be in possession of an image. It is hard to understand what the author is hand-wringing about. It is not that nobody knows how these weapons are supposed to work. The real barrier is that to obtain the materials necessary you need a big-ish industrial base and if you do that that leaves signatures the relevant agencies can detect.
It is not even clear if when he speaks about "safe" is he talking about being safe from nuclear proliferation, or safe from clueless bureaucrats causing you legal trouble.
Probably the guy who produced that part of the graphic was not told what a thermonuclear warhead actually looks like, because he didn't need to know, so he just whipped up his own idea of it from speculative public images. Knowing that the graphic came from somebody who didn't actually know anything, the censors didn't see the need to worry about it.
> Knowing that the graphic came from somebody who didn't actually know anything, the censors didn't see the need to worry about it.
That is not how nuclear secrets work. The US Department of Energy holds that restricted data (a special kind of classification that only applies to nuclear secrets) is "born secret". That means, even if you come up with a concept for a nuclear weapon completely independently without ever talking to anyone, it is considered classified information that you are not allowed to redistribute. This doctrine is highly controversial and the one time it has been tried in court the verdict was inconclusive, but to this day it is how the DoE interprets the Atomic Energy Act of 1954.
In general this is very precarious to attempt to enforce, of course. If the DoE sues someone because they published their nuclear weapon designs, that'd be seen as a tacit admission that the design could potentially work. Nevertheless they actually did do this at one point (United States v. Progressive, Inc., 1979).
One thing he doesn't consider: Perhaps if they do not call it a nuclear warhead, or place it in the context of a larger drawing that tells you it's a warhead, having a sort of blobby, colorful model shape is considered plausibly nonsensical enough that it doesn't matter to the censors.
Powerpoint slides are such a hilarious opsec risk.
When @Snowden blew the whistle on the NSA spying operation, all he did was download everybody's powerpoint presentations and send them to @andygreenwald.
That would have made a good Silicon Valley plot: they discover they accidentally put a trade secret in their logo, and have to jump through hoops to collect, hide, and delete the bad version without making competitors curious about their effort.
For anyone interested in the basics of nuclear weapons, I highly recommend the "Nuclear 101: How Nuclear Bombs Work" lectures by Matthew Bunn, a man heavily involved in nuclear arms control.
His lectures are always highly entertaining, a real pleasure to watch.
This is a clip from his lecture explaining the basics of thermonuclear warheads:
Given the nature of nuclear weapons work, isn't anything presented by someone basically speculation? If he actually had the information he wouldn't be able to talk about it. He seems to have been involved at the government level in the storage and handling of weapons, not production of them.
> I happened to look at a slide deck from Sandia National Laboratories from 2007 that someone had posted on Reddit late last night (you know, as one does, instead of sleeping), and one particular slide jumped out at me:
The author is making fun of themselves for being up late reading this deck instead of sleeping. They’re not making fun of the person who posted the slide deck.
It's not a diagram or mock-up, it's a direct representation of the real thing for computer simulations, similar to CAD. The dimensions and shape of the components are accurate. And the author is calling it a logo because the picture is used to represent and advertise the software.
And why wouldn't they? As wikipedia states, SNL's mission includes "roughly 70 areas of activity, including nuclear deterrence, arms control, nonproliferation, hazardous waste disposal, and climate change."
gnfargbl|1 year ago
Overall this looks like someone asked a physics undergraduate to spend an hour imagining roughly how the well-known schematic might be fitted inside a real warhead case. It probably is exactly that. I can't imagine that showing it to the North Koreans advanced their nuclear programme by any more than fifteen minutes.
defrost|1 year ago
In two decades of crawling through most of the declassified public nuclear material from the US nuclear weapons program, some exposure to classified material, and numerous hours of interviews with working and retired nuclear scientists he believes it's the single most detailed schematic of an actual specific type of warhead he's seen so far.
https://blog.nuclearsecrecy.com/about-me/
https://en.wikipedia.org/wiki/Alex_Wellerstein
As he's blogging about this it's almost certain he has had real current working nuclear weapons experts from his contact list read the advances and not disagree.
Correct or not, it's not a casual random thought from someone with no exposure to such diagrams.
matthewmcg|1 year ago
Figure 13.9, “Unclassified Illustration of a Staged Weapon (Source: TCG-NAS-2, March 1997),” from the Nuclear Matters Handbook 2020 (Revised), published by Deputy Assistant Secretary of Defense for Nuclear Matters.
Two circles in a box, maybe inside of a reentry vehicle. That’s it. Nothing that gives any actual sense of size, location, materials, physicality.”
SiempreViernes|1 year ago
mhh__|1 year ago
I also doubt it's useful, but Ted Taylor could supposedly walk around a room full of nukes and guess based on the shape of the casing what was unique about a design
evo|1 year ago
bryant|1 year ago
The next paragraph details what the author would have expected to be published by comparison.
And then figure 13.9 is what the DoD expects to see published at all.
tivert|1 year ago
Read the article and look at the "officially sanctioned" diagram. This looks like the tl;dr of what he things about this:
> Anyway, I’m just surprised the DOE would release any image that gave really any implied graphical structure of a thermonuclear secondary, even if it is clearly schematic and meant to be only somewhat representative. It’s more than they usually allow!
This linked post of his about an earlier redaction mistake also makes it clear (https://blog.nuclearsecrecy.com/2021/05/17/how-not-to-redact...):
> ...but we’re given a rare glimpse inside of modern thermonuclear warheads. Now, there isn’t a whole lot of information that one can make out from these images. The main bit of “data” are the roughly “peanut-shaped” warheads, which goes along with what has been discussed in the open literature for decades about how these sorts of highly-efficient warheads are designed. But the Department of Energy doesn’t like to confirm such accounts, and certainly has never before let us glimpse anything quite as provocative about these warheads. The traditional bomb silhouettes for these warheads are just the dunce-cap re-entry vehicles, not the warheads inside of them.
ianburrell|1 year ago
Presumably there are uses that need old steel but they are probably smaller amounts.
beezle|1 year ago
unknown|1 year ago
[deleted]
thadt|1 year ago
Any further use isn't very surprising. Once it is approved and in the wild, re-using it is not really a problem (especially if being run through the same office for approval again).
mannyv|1 year ago
taneliv|1 year ago
> ... at least historically, the Atomic Energy Commission and its successor organizations have frowned on disinformation and misinformation for other very practical reasons. If you release a lie, you run the risk of someone noticing it is a lie, which can draw more attention to the reality. And even misinformation/inaccuracy can put “brackets” around the possibilities of truth. The goal of these organizations is to leave a total blank in the areas that they don’t want people to know about, and misinformation/disinformation/inaccuracy is something other than a total blank.
In other words, the author expected to see a previously familiar schematic or nothing. This is clearly not nothing, and also not a familiar schematic, hence the surprise.
Log_out_|1 year ago
snowwrestler|1 year ago
But here’s the thing: that internal culture is just as opaque to outsiders as the technology itself! No outsider actually knows how the internal folks think, feel, and decide about little graphics or schematics or whatever. They’ve just inferred some heuristics from incomplete data.
And this is basically just saying “this little graphic seems to violate my heuristics.” Which makes for interesting reading, but there is no real actual objectively verifiable content in this article.
Betteridge’s Law tells us the answer to the headline question is always “no.” And in this case I think common sense agrees: Sandia Lab probably did not give the entire thermonuclear ballgame away with a logo graphic.
ein0p|1 year ago
freestyle24147|1 year ago
sandworm101|1 year ago
(Note that nuke warheads fall nose-first, the opposite of space capsules. So the dense material is packed in the nose, with the lighter stuff at the back.)
The nearby disk looks like a represention of airflow around a falling warhead. They, like apollo, likely had an offset center of gravity that allowed them to stear by rotation, creating the asymetrical airflow shown on the disk. Falling in a spiral also probably frustrates interception. So that whole corner of the image is advertising Sandia's ability to do aerodynamic simulations.
beerandt|1 year ago
You have a technical expertise just close enough to, but firewalled from the actual doe nk physics, where maybe the same image couldn't be released by anyone with doe clearance.
But the guy a few buildings over just doing 'hypothetical' center of gravity modeling? Doesn't necessarily have to live by the exact same rules or go through the same release/declass process as someone with actual weapons schematics.
It leaves a lot still unanswered- but explains away some of the seemingly self- contradictory Sandia policy discussed in the article.
In industrial speak: inside-the-fence vs outside-the-fence regulatory framework, or something similar.
Sometimes the guy outside the fence 'gets away with things' because those things are OK to do outside the fence.
thedrbrian|1 year ago
jiggawatts|1 year ago
People very quickly figured out that this was the source of the D-T fuel in fusion part of the bomb instead of cryogenic D-T liquid. Lithium Deuteride is nasty stuff, but it's a storable solid. When bombarded with neutrons from the fission primary, the Lithium splits and forms tritium, which then combines with the deuterium that was the other half of the crystal.
The reason the usage was obvious (from the title alone!) is that very few chemists would care about any property of Lithium Hydride, which is dangerous to handle and has few practical uses. Lithium Deuteride is unheard of in analytical chemistry, and its crystallography under high pressure is totally uninteresting to anyone... except physicists working on atomic weapons.
mjevans|1 year ago
I'm reminded of CGP Gray's videos about flags. https://www.youtube.com/user/cgpgrey/videos Like this one https://www.youtube.com/watch?v=l4w6808wJcU About US state flags
chefandy|1 year ago
The most frustrating thing about being a designer in those environments is the dunning-krueger cockiness many technical people have in their understanding of design, which they usually believe is purely an aesthetic consideration.*
It's not even like a junior developer trying to 'correct' a senior developer about coding practices in a dev meeting— the better analog is a designer that watched a half hour Coding for Designers talk at a conference trying to correct a senior developer about coding practices in a stand-up, because they'd never have been invited to the dev meeting to begin with. If there were only designers in that meeting— and they likely find the other designer more credible because they jibe with their perspective, don't realize how important the developers input is, and might have watched that same conference talk— that could damage a project. In my experience, designers are way more likely to be solo in meetings with developers and the echo chamber of developer 'expertise' on design drowns out actual professional design expertise. In most FOSS projects, is bleaker than that because designers don't even bother trying.
* though completely out-of-context "rules" born from Tufte quotes aren't uncommon. In art school, we were told that we need to understand the rules in order to know when to break them. Imagine someone who'd never driven before that memorized a few pages of the driving manual calling you an unqualified driver because your actions didn't comply with the letter of one page they memorized even if it was qualified by another, or required for safety.
permo-w|1 year ago
lukas099|1 year ago
simplicio|1 year ago
Wonder if this isn't something similar, if the DoE has some sort of "standardized notional warhead" design they can use to give to outside researchers without having to give every post-doc and grad-student a security clearance.
squeaky-clean|1 year ago
> MACE (Modal Analysis Correlation Exercise) assembly, and was created by the UK Atomic Weapons Research Establishment in the 1990s to serve as a sort of a Utah Teapot of weapons structural modeling: a benign shape that could be used to test aspects of the code that would nonetheless tell you if the code would work for real weapons assemblies.
walrus01|1 year ago
bee_rider|1 year ago
The Sandia folks may be extra special, it is a pretty famous place. But engineers are people first of course, so lots of variation. And also, some are super serious of course, but there are hacker tendencies, playful tendencies. I bet if some intelligence agency folks wanted to, they could find some engineers out there who’d be receptive to this sort of thing.
If it is a fake, known-stupid design, including it would be a funny prank that wastes the time of people that might want to nuke us, right?
csours|1 year ago
writeslowly|1 year ago
zubiaur|1 year ago
hbossy|1 year ago
taneq|1 year ago
splonk|1 year ago
buran77|1 year ago
kingkongjaffa|1 year ago
In order to mesh the geometry for finite element analysis, the geometry virtually always needs to be defeatured.
So the cross sectional CAD model here is a nice curiosity but basically useless for any reverse engineering purposes which is the key reason this stuff is kept secret.
weinzierl|1 year ago
I did finite element model preparation for a living many year ago and it did not only involve heavy defeaturing but interestingly also remeshing with quads.
Renderers love triangles, FE solvers love boring quads.
thrwooshfem|1 year ago
This story is probably nothing interesting because this went through all the public use approvals needed for public presentations and being available on osti.gov.
It is probably just a toy test problem used on a capabilities logo for Sierra. Maybe it comes from some sort of integration test that is easier to run than the actual problem.
BWStearns|1 year ago
https://www.amazon.com/Arms-Influence-Preface-Afterword-Lect...
_n_b_|1 year ago
closewith|1 year ago
> It’s literally the logo they use for this particular software package.
Which seems to refer to the image of the re-entry vehicle in isolation from the infographic where the author originally found it.
lupire|1 year ago
shahzaibmushtaq|1 year ago
Other than that, I'm not so sure about the particular design pointed out by the author.
smiley1437|1 year ago
aidenn0|1 year ago
QuadmasterXLII|1 year ago
ajsnigrutin|1 year ago
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HelloNurse|1 year ago
eesmith|1 year ago
> Someone reminded me of something I had seen years ago: the British nuclear program at Aldermaston, when it has published on its own computer modeling in the past, used a sort of “bomb mockup” that looks far more deliberately “fake” than this Sandia one. I offer this up as what I would think is a more “safe” approach than something that looks, even superficially, like a “real” secondary design:
> This is called the MACE (Modal Analysis Correlation Exercise) assembly, and was created by the UK Atomic Weapons Research Establishment in the 1990s to serve as a sort of a Utah Teapot of weapons structural modeling: a benign shape that could be used to test aspects of the code that would nonetheless tell you if the code would work for real weapons assemblies.
cm2187|1 year ago
AnimalMuppet|1 year ago
IIRC the story, this was still during WWII. They were testing the flight characteristics of the bomb casing. It did not contain a core. But it was still extremely classified. They had the test casing in the back of a truck, taking it from Sandia to Kirtland AFB. The truck got in an accident, the tailgate fell open, and the bomb casing fell out and went rolling around in the street.
avar|1 year ago
I think the author is omitting the most likely explanation for why it wasn't redacted in future publications.
It took from 2007 to 2024 for someone (him) to publicly notice this.
If your job was to censor documents coming out of Sandia National Laboratories, and you screwed up this massively, what's your incentive to call attention to your screw-up?
Better to just coast along, by the time you retire or move on to another job your ass is off the firing line.
Ditto (but less so) if this was your co-worker or team mate, after all North Korea, Iran etc. already have access to the published document.
What could anyone in your organization possibly gain from the ensuing shitstorm of admitting something like that?
Has this person worked, well, pretty much anywhere, where people have a stronger incentive to cover their own ass and keep out of trouble than not?
Or, that internal report and subsequent shitstorm did happen, but what do you do at that point? Make a big public fuss about it, and confirm to state actors that you accidentally published a genuine weapons design?
No, you just keep cropping that picture a bit more, eventually phase it out, and hope it's forgotten. Maybe they'll just think it's a detailed mockup of a test article. If it wasn't for that meddling blogger...
Edit: Also, I bet there's nobody involved in the day-to-day of redacting documents that's aware of what an actual weapons design looks like. That probably happens at another level of redaction.
So once something like this slips by it's just glazed over as "ah, that's a bit detailed? But I guess it was approved already, as it's already published? Moving on.".
Whereas a censor would have to know what an actual thermonuclear device looks like to think "Holy crap! Who the hell approved this?!". And even then they and the organization still need the incentive to raise a fuss about it.
kridsdale3|1 year ago
jjk166|1 year ago
Updating a logo (especially a bad logo) after a couple of years is not exactly a newsworthy event. If you replaced any other part I would not assume it was to correct an accidental disclosure of classified information.
numpad0|1 year ago
jjk166|1 year ago
joegibbs|1 year ago
PaulHoule|1 year ago
The fission stage in that warhead has numerous refinements that help miniaturize it, for instance the implosion is probably not spherical so it can fit in the pointy end of the warhead. A really refined modern weapon is packed with details like that.
krisoft|1 year ago
It is not even clear if when he speaks about "safe" is he talking about being safe from nuclear proliferation, or safe from clueless bureaucrats causing you legal trouble.
lupusreal|1 year ago
renhanxue|1 year ago
That is not how nuclear secrets work. The US Department of Energy holds that restricted data (a special kind of classification that only applies to nuclear secrets) is "born secret". That means, even if you come up with a concept for a nuclear weapon completely independently without ever talking to anyone, it is considered classified information that you are not allowed to redistribute. This doctrine is highly controversial and the one time it has been tried in court the verdict was inconclusive, but to this day it is how the DoE interprets the Atomic Energy Act of 1954.
In general this is very precarious to attempt to enforce, of course. If the DoE sues someone because they published their nuclear weapon designs, that'd be seen as a tacit admission that the design could potentially work. Nevertheless they actually did do this at one point (United States v. Progressive, Inc., 1979).
relaxing|1 year ago
That’s not really true. If you manage to independently come up with classified info and release it to the public, you will get a visit from an agency.
Overall I think you’re correct.
niemandhier|1 year ago
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ggm|1 year ago
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declan_roberts|1 year ago
When @Snowden blew the whistle on the NSA spying operation, all he did was download everybody's powerpoint presentations and send them to @andygreenwald.
tripzilch|1 year ago
sandos|1 year ago
ceejayoz|1 year ago
tabtab|1 year ago
unknown|1 year ago
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dwighttk|1 year ago
Where did he end up? Intentional misinformation? It was definitely not clear but that was the last one he listed…
virgulino|1 year ago
His lectures are always highly entertaining, a real pleasure to watch.
This is a clip from his lecture explaining the basics of thermonuclear warheads:
https://youtu.be/YMuRpx4T2Rw
And the full “Nuclear 101” lecture, in two parts:
https://youtu.be/zVhQOhxb1Mc
https://youtu.be/MnW7DxsJth0
nirav72|1 year ago
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aaron695|1 year ago
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mhh__|1 year ago
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felipelemos|1 year ago
After a couple of decades of internet I was expecting people to realize other timezones exists.
diab0lic|1 year ago
> I happened to look at a slide deck from Sandia National Laboratories from 2007 that someone had posted on Reddit late last night (you know, as one does, instead of sleeping), and one particular slide jumped out at me:
The author is making fun of themselves for being up late reading this deck instead of sleeping. They’re not making fun of the person who posted the slide deck.
mxfh|1 year ago
ibeff|1 year ago
dredmorbius|1 year ago
pantulis|1 year ago
KeplerBoy|1 year ago