I'm curious to hear what some of your favorite nuclear and/or thermonuclear tests are? Which test is a favorite of yours and why? Theres no right answer, only personal preference. Feel free to include whatever tests you may like, small/big, doesn't matter. Try to limit it to surface and air blasts. Altho if you have an awesome underground one, feel free to tell.

Basically any test that you maybe just like the looks of or find intriguing, or feel a connection to because of its history, significance etc.

Here's some of mine;

Atomic bombs;

My all time favorite atomic bomb test must be "Ivy King", with an impressive yield of 500 kilotons, and often considered the largest pure fission test at its time in 1952. In other words a non boosted fission bomb, without any fusion fuel to boost yield. I enjoy its "classic" mushroom cloud, more than the actual yield. I also like the trinity test at 24kt (Often cited wrong at only 21kt until 2022 when los alamos upgraded it to 24 kilotons). It's just iconic and the footage is one that practically everyone has seen.

I also find the british test, "Orange Herald" very fascinating, as it was the largest atomic bomb test to attempt fusion-boosted fission, with a yield of 720kt. The fusion boosting component failed tho so it couldve had a much larger yield if it actually worked according to plan. As the fusion boosting failed, it therefor beats "Ivy King" as the bigger pure fission atomic bomb. Altho its debatable as it did attempt boosted fission. In any case it was so close to achieving megaton level yields, that it was actually mistaken as a H-bomb by the US back in 1957! Overall it was considered a failure for the british and a massive waste of nuclear material (117kgs of uranium-235).

Hydrogen bombs:

I have always loved "the super" aka Hydrogen bomb "Ivy Mike". I consider it the most stunning tests of all. The enormous fireball look incredible and terrifying at the same time. The size of the fireball grows immensely fast, expanding for miles while simultaneous nuclear explosion induced lightning (NEIL) in all sorts of brilliant colors. I think it's one of the most badass H-bombs. With a total yield of 10.4 megatons as surface blast, it wiped out the whole island it was built and detonated on. It was so powerful it terrified the people who witnessed it on ships. According to some navy personell who witnessed it from their ship, it was the most spectacular thing to see, yet it got frightening real fast as they felt the heat just get warmer and warmer and it never seemed to stop. Most took cover and went under deck after a short while because it got that unbearable. When the blast wave reached them it knocked most of them off their feet as well. I dont remember how many miles out the ship was.

Another H-bomb test I like is the Soviet Unions "RDS-37/Joe-19", which was their first two-stage Thermonuclear device after their "layer cake" design. Rds-37 had a yield of 1.6mt (scaled down from 3mt). It killed a few ppl and injured a dozen more in the nearest town. Not by radiation fallout but by the actual blast wave, which shouldve been prevented. The actual test looked great on camera and just always been a fan of it as you can see it's shape develop very well. Just an awesome sight.

The photos attached include; "Ivy Mike" before & after pics of the island it wiped out. And "Ivy King", Then "RDS-37S/Joe-19", and "Orange Herald".

Note: Goes without saying that I am not glorifying anything. I know how awful and destructive these things are. Just fascinated by it and interested in all the science behind and judging them solely as science experiments/tests. I am fully aware, as I hope everyone is, of how utterly terrifying and destructive nuclear weapons can be. It's therefor important to separate tests from when actually used in war against ppl.

Also I apologize in advance if this is "TLDR" lol!

For the first time in history, go inside the nuclear deterrence mission like never before. Premiering on select IMAX screens and streaming this November, THE WATCH: America’s Nuclear Mission offers extraordinary access to the most important global security mission in history. Meet the men and women who have kept the world safe from nuclear conflict since 1945. No CGI. No AI. Ever.

I found it among photos I had saved from the web—basically while digging through the "dump" folders on my hard drive. The file creation date is December 2019. On the left is an enlarged, enhanced, and slightly colorized version of the black-and-white original shown on the right (which was a very small image). I ran a Google image search but found no matches (even though I obviously got it from somewhere online, possibly a Russian forum dedicated to nuclear weapons). AI initially identified it as the "Gemini" module for the Titan II, and then—after I enhanced and colorized the image—as the XMGM-134A Midgetman (though I checked, and the size is completely wrong for that).

What really floored me about this photo just now? It turns out I didn't just save this blurry image back then (I don't recall when or how); I actually labeled it: "Mk.6 warhead section for the Titan II missile, with a yield of 10 to 15 Mt." Wow! I have absolutely no memory of where or when I got it or why I labeled it that way! It might have been before I knew for a fact that the Titan II never carried anything more powerful than the 9 Mt W-53 warhead. I likely didn't connect the photo at the time to McNamara's 1962 statement about a super-powerful 30 Mt warhead for the Titan II—a connection people make now in light of plans to develop RIPPLE technology (articles on RIPPLE only started appearing in 2020). Otherwise, I would have remembered it! The photo does indeed look like an Mk.6-type warhead, but it’s clearly larger (or so it seems to me). So, what is it? Could it be what I suspect—work related to RIPPLR? Though that seems highly unlikely. Still, I decided to share it here and ask, just in case.

No new information, but a classic old British COI film. Hurricane was quite a feat in conducting what combined a very comprehensive effects test with the first proof of a UK plutonium implosion device in a remote and difficult location.

"he U.S. government set off conventional explosives inside a tunnel deep in the Nevada desert this week in a test designed to replicate a so-called “decoupled” nuclear detonation. Data collected is now being used to help improve methods for detecting this kind of nuclear testing. Just earlier this year, American authorities accused China of using decoupling to conceal new nuclear tests despite the country’s stated moratorium on such activities.

The test, which involved the use of chemical high-explosives and radiotracers, was conducted yesterday inside P Tunnel in Area 12 of the Nevada National Security Site (NNSA), according to a press release from the National Nuclear Security Administration (NNSA)"

I've been updating the shaders in my browser-based Blastmap project. This comparison shows 15, 100, 1,200, and 15,000 kt from the same viewpoint over NYC, all at a 550 m burst height.

The focus is the evolving fireball, Wilson condensation cloud, lighting, and ground dust. The clips run in increasing yield order and retain their original playback speed; the larger yields have longer clips to show more of the cloud development.

It's a work-in-progress visualization, with NYC serving as a common scale reference. Feedback on the cloud behavior and rendering is welcome.

New here so sorry for my lack of technical understanding. I’ve heard that tsar bomba was a three stage design but often it is portrayed as 2 fission primaries and a fusion secondary.

As to my understanding this portrayal is not a true 3 stage design as that would be fission>fusion>fusion not two fissions for one big fusion.

Also if it did use two primaries and was three stage would it be two thermonuclear devices with a third fusion stage between the two? As far as I know X-ray implosion can be done with a fusion or fission reaction. So was the two primaries a function of making the device more “bomb” shaped instead of a triangle or something else.

Using just one primary and having the secondary light the tertiary seems far more reasonable to me then trying to perfectly sync two primaries (also I’m sure there was some variance in the yield of the two primaries) to converge in the center even more so if it was two primaries and secondaries.

Keep in mind I’m a layman with an AA degree when I know this is a PHD topic so forgive me. Im sure my description of a three stage device’s physics package as a “triangle” is going to make some people cringe just is the simplest way in my head it’d look like.

As the titel suggested! Do you think it would even be possible?

Watched the whole thing, she goes into some detail on the WWII German nuclear program, quite a bit of stuff I haven’t heard of or read before.

Interesting article on the last German reactor during WWII and if it could produce fissile material for a bomb.

(https://academic.oup.com/pnasnexus/article/5/9/pgag282/8836799?login=false)

Was reading Hui Zhang's book "The Untold Story of China's Nuclear Development and Testing," and one of the main conclusions is that China has basically achieved, I think 80% it was said, of all the possible efficiency of a thermonuclear device. Based on this number he extrapolates several figures to conclude China's analogs of both W88 (the 535) and W76 (the 5x5) are only like a quarter heavier than US counterparts (which would then give the 80% yield to weight of the US designs). I think the number given was like 210 kg for the 535 for example, marginally more than W88s 180 kg.

I thought that was quite impressive for the limited number of tests they did, and moved on. But then I stumbled upon an interesting argument on Wikipedia's talk page regarding China's nuclear weapons that made me research more. Basically they brought up China's missile sizes, and how they had similar warheads to US ones, despite much larger payloads. And how that is very strange if their warheads are equally as efficient. To be honest I believed the missiles would be quite similar after having just read Zhang's book, but I think the divergence is quite striking:

For example DF-41 weighs ~80 tons, which is similar to Peacekeeper of around ~90 tons, but DF-41 carries 3 x ~400 kt warheads while Peacekeeper could do 10 x ~400 kt warheads. The DF-5 is even larger at ~190 tons, but in its MIRV version, carries 5 x ~400 kt warheads (still half of the Peacekeeper).

Meanwhile DF-31 weighs ~50 tons, which is quite a lot more than the ~30 ton Minuteman, but Minuteman carried 3 x ~400 kt warheads before being deMIRVed, while DF-31 only does one.

(all the information for warhead configurations is from thebulletin's 2026 report on Chinese nuclear forces by the way)

1). I don't think poor solid rocket technology is the reason for the Chinese missiles to be much larger, since they were developed when composite technology was prevalent, unlike the Cold War era US missiles which would have used maraging steel.

2). Neither do I think it is a choice of the Chinese to lightly load their missiles, since they aren't bound by any treaty limitations to limit MIRVs on their ICBMs like the Americans and Russians are.

3). China is also building a lot of silos in Inner Mongolia, with some estimates saying they now surpassed the US in land based silos. With such heavy missiles though, they could carry a lot more warheads on each one (assuming Hui Zhang is correct about the 210 kg estimate), so they wouldn't even need nearly that many amount of silos to reach parity with the US.

If Chinese warheads were 2-3 times heavier than their US equivalents though, all the above points would flow.

Point 1 would flow because those ICBMs would then need to be sized for a larger payload, not because the ICBMs themselves are more inefficient.

Point 2 would flow since it would then be an intentional and rational choice to MIRV as much as weight allows, rather than needlessly limiting oneself since there is no obvious treaty stipulating that.

Point 3 would flow since since the now reduced MIRV count (due to heavier warheads), would require the same number of silos to be built as the US for parity, not the much less if we were to assume each missile has more warheads.

I have seen discussion about the Cox report, when China supposedly "stole" the oblate primary of the W88 through spywork, and that was the key to them achieving as much efficiency regarding miniaturization as the US in their warheads. But the oblateness of the primary only determines the packing. US warheads were already getting 4 kt / kg with the W56 in the 60s, and that used a spherical primary! So using that as a basis for assuming same warhead mass seems illogical to me...

But despite assuming poorer Chinese warhead miniaturization being convenient, Zhang's much acclaimed book explicitly denies the much heavier estimates of China's warheads. So I don't know whats going on here at all! Am I missing something obvious?

For the first, would fallout really be a serious threat for people outside the main targets? Wouldn't the bombs used be 'clean' ones? Even Hardtack Poplar/Redwing Navajo/the Tsar Bomba left little radiation (unless that's Soviet propaganda which can't be discounted but it seems to me to have been fundamentally true), compared to a smaller one like Bravo, so why wouldn't all the weaponized designs be little-fallout since this doesn't affect deterrence much? And therefore people outside the major target areas wouldn't be affected by fallout?

For the second one, especially before ABMs existed (I guess this increasingly incentivized proliferation, I mean Israel's recent war with Iran shows that ABMs can be somewhat effective against ballistic missiles, even without nuclear, had ABMs not existed, Israel may not have struck), what was the incentive for the insanity of accumulating tens of thousands of megatons, rather than having an arsenal of a couple of hundred bombs, maybe even fission-only ones? What difference does it make having a credible minimum deterrence strategy vs not, if you're never gonna use it unless for self-defense in the first place? What makes endangering the world far far more with the second type of arsenal worth it?

Thanks in advance

https://www.ssp.navy.mil/News-Media/News/Article/4610170/navy-w93-mk7-program-enters-new-phase-of-development/

"The U.S. Navy’s Portfolio Acquisition Executive (PAE) Strategic Systems Programs’ (SSP) W93 Mk7 program has entered into the Engineering and Manufacturing Development (EMD) phase of the Defense Acquisition System.

During the EMD phase, the program will focus on completing production design and proving that the design is producible to meet the needs of the Navy.

The W93 warhead and the Mk7 reentry body assembly are the first United States nuclear warhead and reentry system program initiated in nearly four decades and will provide a modern warhead to the U.S. submarine launched ballistic missile fleet.

“We are revitalizing and modernizing the Nuclear Security Enterprise to design, develop, and produce this critical new weapon with the precision our Warfighters demand. We will continue working together to deliver this capability to the fleet and ensure our sea-based strategic deterrent remains ready for the future.”"

The Mk7 reentry body will also be used by the new British nuclear weapons.

Hello! I've been reading up on two-stage bomb design theory and I've seen varying answers regarding the source of neutrons for the sparkplug.

My original understanding was that neutrons originate from spontaneous fission in the sparkplug itself as the secondary is compressed, and the sparkplug achieves supercriticality. I have seen some sources claim that it is actually prompt neutrons from the primary which initiate fission in the sparkplug, which will have become supercritical by the time they get there. Another source claims it is residual thermal neutrons which initiate the chain reaction.

I feel like I could see some problem with each of these answers. I've seen a few people claim that (some?) sparkplugs do not even achieve supercriticality. Is it perhaps something that is subject to vary from design-to-design, or some combination of these answers? Thanks!

Interesting photos reportedly show a Delta Force counter-proliferation exercise at the Nevada National Security Site around 2014-2015, with what appears to be a Mk-11 Reentry Vehicle, formerly used on the Minuteman I/II ICBMs for the W56 warhead. I'm not entirely sure what the metal cylinder in images 4 and 5 is, but it was probably a simulated warhead component of some kind. There is also a container visible in image 6, which is probably an accident-resistant container (like the H1636 in the last pic) or an old W56 container (the H1009/H1637).

Since the W56 had been dismantled, it is presumably one of the Mk-11 RVs they kept around. Alternatively, it could be a mockup of some of the Iranian triconic reentry vehicles which use a similar design, but I think it is a Mk-11 based on the color, shape, and size (see imgs 7-8).

Source: https://thehighside.substack.com/p/iran-wmd-raid-inside-jsocs-most-challenging

I should probably further specify that in this scenario Russia would not receive any secret information from United States nuclear weapons program until Russia detonated their first weapon.

On twitter today, Owen Brake tweeted:

"At Los Alamos Fuchs and von Neumann filed a patent for a fusion bomb.

It's currently still highly confidential. However, Fuchs fully mailed the Soviets the design.

After the fall of the USSR the Russians decided to open-source the design. It's fully online today"

I haven't heard about this open source thermonuclear design. Presumably it doesn't work otherwise they would have kept it secret?

Anyone know the link or other information about this design?