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.<p>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.
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.<p>(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.)<p>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.
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."<p>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.<p>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 <i>under high pressure</i> is totally uninteresting to anyone... except physicists working on atomic weapons.
That thing is supposed to be a logo?<p>I'm reminded of CGP Gray's videos about flags. <a href="https://www.youtube.com/user/cgpgrey/videos" rel="nofollow">https://www.youtube.com/user/cgpgrey/videos</a> Like this one <a href="https://www.youtube.com/watch?v=l4w6808wJcU" rel="nofollow">https://www.youtube.com/watch?v=l4w6808wJcU</a> About US state flags
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.<p>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.
> 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.<p>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.<p>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 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?
The author is u/restricteddata on Reddit. This appears to be the thread that inspired this post: <a href="https://www.reddit.com/r/nuclearweapons/comments/1f85zpi/mk4a_mk5_dimensions/" rel="nofollow">https://www.reddit.com/r/nuclearweapons/comments/1f85zpi/mk4...</a>
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.<p>In order to mesh the geometry for finite element analysis, the geometry virtually always needs to be defeatured.<p>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.
Tangentially: I wonder if the checker badge is a visual pun on the Arms and Influence cover.<p><a href="https://www.amazon.com/Arms-Influence-Preface-Afterword-Lectures-ebook/dp/B00FC655Q6" rel="nofollow">https://www.amazon.com/Arms-Influence-Preface-Afterword-Lect...</a>
For everyone complaining that it's an infographic, not a logo, that's addressed in the article:<p>> It’s literally the logo they use for this particular software package.<p>Which seems to refer to the image of the re-entry vehicle in isolation from the infographic where the author originally found it.
In the era of CDs/DVDs and according to year 2007 perspective, these types of infographic logos were quite common.<p>Other than that, I'm not so sure about the particular design pointed out by the author.
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.
Heh. Ask my mother about the time that Sandia dropped an atomic bomb casing in the streets of Albuquerque.<p>IIRC the story, this was still during WWII. They were testing the flight characteristics of the bomb casing. It did <i>not</i> 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.<p>I think the author is omitting the most likely explanation for why it wasn't redacted in future publications.<p>It took from 2007 to 2024 for someone (him) to publicly notice this.<p>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?<p>Better to just coast along, by the time you retire or move on to another job your ass is off the firing line.<p>Ditto (but less so) if this was your co-worker or team mate, after all North Korea, Iran etc. <i>already</i> have access to the published document.<p>What could anyone in your organization possibly gain from the ensuing shitstorm of admitting something like that?<p>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?<p>Or, that internal report and subsequent shitstorm <i>did</i> 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?<p>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...<p>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.<p>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.".<p>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.
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?
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.
The entire half round with an inner core is surely half an explosively compressed primary. And, it's not a "logo" it's an infographic.
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.<p>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.
>That’s where I’ve ended up…<p>Where <i>did</i> he end up? Intentional misinformation? It was definitely not clear but that <i>was</i> the last one he listed…
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.<p>His lectures are always highly entertaining, a real pleasure to watch.<p>This is a clip from his lecture explaining the basics of thermonuclear warheads:<p><a href="https://youtu.be/YMuRpx4T2Rw" rel="nofollow">https://youtu.be/YMuRpx4T2Rw</a><p>And the full “Nuclear 101” lecture, in two parts:<p><a href="https://youtu.be/zVhQOhxb1Mc" rel="nofollow">https://youtu.be/zVhQOhxb1Mc</a><p><a href="https://youtu.be/MnW7DxsJth0" rel="nofollow">https://youtu.be/MnW7DxsJth0</a>
> at someone had posted on Reddit late last night (you know, as one does, instead of sleeping)<p>After a couple of decades of internet I was expecting people to realize other timezones exists.
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."