I can _kind of_ understand the first accident. It was the very early days of a new technology; the regulations hadn't yet been written; society was much less safety-conscious in general (fun fact: when Ford began offering seat belts as a option in 1955, fewer than 2% of buyers opted for them). What I can't fathom is watching your friend and colleague die a preventable, slow, horrific death, then going on to do something even _more_ senselessly dangerous-and putting seven other people at risk! It's simply unthinkable.
My father, a U.S. Navy aviator, piloted an aircraft loaded with scientists and instruments at the Castle Bravo nuclear weapon test. 6 megatons were expected; we got 15. Turns out there's a difference between Lithium-6 and Lithium-7. Turns out that extra neutron matters. And lots of folks in the test got a lot more irradiated than expected. He died at age 49 (when I was very young) with half a dozen kinds of cancer. Lung cancer, kidney cancer, melanoma, leukemia, CRC, pancreatic. VA tried to say it wasn't service related to deny benefits.
We owe so much to the early pioneers that risked their lives, often unknowingly, for all the knowledge we've gained from their sacrifices. The government should recognize them all retroactively and compensate families that had loved ones become ill and die from exposure to toxic or radioactive materials while working for or serving our country. Especially for those who became terminally ill and were told it wasn't related to their service and denied any recognition or benefits. Even today our veterans still aren't being taken care of the way they deserve to be.
@kristianniss5201 zero empathy moment. I bet you'd be the kind of person to deny benefits to veteran families who lost their loved ones due to their time in service
The "flat-head screwdriver incident" is directly referenced in a mid-game level in the civil-engineering-'em-up _INFRA._ You find a _suspiciously familiar_ half-dome and sphere setup in a certain spoilery area, along with a written note that ends with "I don't care how good your 'prestidigitation' is. If that reflector locks in, WE'RE ALL DEAD!". Being a video game, you can, ahem, do the obvious thing (complete with blinding flash of white as Mark dies), and get an achievement for it!
I was lucky to read an article in "The New Treasury of Science" as a kid called "The Death of Louis Slotin". This was a good thing for a science kid to read. It not only gave me a healthy respect for radiation, but tended to moderate all the dangerous things I was doing with chemistry and electricity that could have harmed be the old fashioned way :) Thanks for the video!
As a licensed electrician and avid organic chemistry fan,(as well as a nerd with everything science, all aspects) I can say that some of the incidents I had as a young guy, while minor, helped keep from from making sincerely bad mistakes when older !
Great review of an equally well done Kyle Hill video. His Half-life series is very well researched and a pleasure to watch. You might want to do a few more of them. I really like how you explain in a clear, concise manner what would be done today, and how experiments like this would not be even almost allowed, full stop. Your channel has fast become one of my favourites because of it👍
My Father-in-Law was a chemist that worked on the Manhatten Project. He helped design the implosion explosives that detonated Fat man. He had so many awesome stories about his time there. He told me of one of his visits to a neuclear reactor where he viewed the core from a catwalk above and could see the blue glow of the reaction below. He passed form liver cancer which no doubt was from his exposure at Los Alamos.
That peer checking and oversight is because of incidents like this. Rules and laws are made because someone did something that necessitated it. Also. My grandfather was at Bikini and was on deck to witness several tests. They gave them welding goggles as their only PPE. He died of a weird form of Parkinson's at 79, which is weird because it not only doesn't run in the family, but most of his brothers and sisters lived into their 90s and 100s.
@@exxor9108 That's the assumption. That and/or defoliants used at guadalcanal and experimental firefighting chemicals in the CDF... or aboard ships. He was exposed to a lot of crazy shit in the 50s and 60s.
The accident is shown in the movie Fat Man and Little Boy. It stars Paul Newman and John Cusack. Btw, 40+ years ago I attended the only high school in America with a radiation lab which had a Cobalt source. Teacher was a physicist who worked at Oakridge during the summer building bombs and taught physics during the school year. Her name was Barbara Reed. High School is Riverview high School in Sarasota. She convinced the school board to have the lab installed so they can study the effects of phosphate mining which is big in that area and what it was doing to the environment because when you dig up phosphate, you dig up the whole uranium decay chain. At the time she told us that there had not been any American civilian deaths from radioactive material. But one day she did a lecture on the accidents that happened to government contractors. With slides. Anyway, because of her in that class I decided to become a radiographer and I was one for 25 years.
That's really cool. You know, as far as she knew, there probably weren't any civil deaths due to radiation. The demon core and other Los Alamos deaths due to radiation were classified into... I think the 70's or 80's.
They didn't build bombs at Oak Ridge. They enriched uranium there. The details of Daghlian and Slotin's deaths were kept secret for a long time after they happened in 46-47. Cool memories.
@@puncheex2 Yes I understand that they didn't actually build bombs there, it was urnium production. This was back during the Cold war. I also met another scientist that had worked at oak ridge. That's when I became an x-ray tech and worked at a doctor's office. We were both talking about being exposed to radiation is how that came up when I was x-raying his knees.
I worked at Los Alamos from 1993 to 2000 for the Dept. of Energy as a nuclear engineer doing safety oversight. One of my assigned areas was TA-18, the Critical Experiments Area, or as it was referred to in the video, Pajarito Site. At about 11 minutes into the video a comment is made that experiments involving prompt criticality are not controllable and would not work, which is not entirely true. During my time there, multiple experiments were completed at prompt critical using the Godiva IV critical assembly. I observed several of them. The Godiva assembly used a safety block that was ejected from the machine by the energy shock wave created when the machine went prompt critical. Since then, the critical experiments facility has been moved to the Nevada National Security Site (previously known at the Nevada Test Site). Obviously, all experiments involving criticality are now done remotely.
iirc the main advantage to using water as a reflector and moderator is that, when the core gets too hot, the water boils and evaporates, meaning it doesn't reflect or moderate anymore, and stops the reaction from going out of control.
Engineer 1: "Hey, want to see something cool?" Engineer 2: "Yeh, wait..... is that a screwdriver holding a top metal dish slightly ajar? Is that a core in the middle?" Engineer 1: "Yup, now the only thing keeping us from getting irradiated and killed is that screwdriver. Hope no one knocks it over.... Oh crap" Engineer 2: "Congrats you just doomed us in the room"
I was in grad school in the late 1980s and had a professor that had work at Los Alamos starting in 1945. He used to tell us all these stories of stuff going on there. Like how they used to align particle accelerator beams by sticking their head into the beam and adjusting ito to get the most light from scintillations from the fluid in their eyes
He never brought up the subject of that mysterious object that crashed near the Trinity site in 1945, did he? Of course, not, he probably never even heard of it. Jacques Vallée wrote a book, recently, about it. It's pretty interesting.
There was a Russian physicist that got zapped in the head by a full strength particle beam because his colleagues didn't know he was working on it at the time. But maybe our host has covered that? Didn't kill him, but it did something to the nerves in his face, like a permanent botox?
Fun fact: The Bikini Atoll mentioned at timestamp 20:18 is where Sponge Bob takes place. Depressing fact: Bikini Atoll was populated, and the residents were forcefully relocated for the tests to an island, but then they started starving to death and were then relocated again. Afterwards they were placed back on Bikini Atoll, but then later when it was noticed the residents carried abnormal amounts of Caesium-137 and the well water carried abnormal counts of Strontium-90 they were evacuated and subsequently lost their homes forever. The Bikini Atoll is now only visited by divers and scientists.
@@Bassalicious A quick google search tells me the most nuked place is Semipalatinsk, but maybe bikini atoll has another situation going on that I don't know about.
@@Bassalicious It might have been known as the most nuked place on earth by Westerners before the fall of the USSR, so Semipalatinsk was probably not well known at the time.
Kyle Hill has a t-shirt, poster, and coffee cup you can buy that hss a diagram drawing of the scientists standing in thier respectively positions around the Demon Core prior to it going critical with the caption "Go ahead, f*ck with it. See what happens!"😊
The recognition of cancers caused by radiation exposure go back to 1902. After WWII, and with names like Feynman, and Enrico Fermi involved in these projects, they most definitely knew about the possible consequences.
Indeed. They didn't treat the risk like we would today because their mindset was different. Their primary concerns were things like the end of the world as we know it, not maybe getting cancer in 20 years. They all knew guys who had gone into greater danger, and guys who hadn't come back.
Hello! I'm newly subscribed to this channel, but I was wondering if you had any plans to make videos explaining some nuclear engineering concepts? I'm currently a college sophomore, but I plan on majoring in nuclear engineering after I get my gen-ed's out of the way and transfer. Maybe just a video explaining what classes you had to take and why they're relevant or something like that. I think a lot of people would be interested - or at least - curious about that. Loving the channel so far!
Have fun on your journey into nuclear engineering! I’ve done a few shorts on some nuclear engineering concepts and misconceptions: Nuclear Engineer Explains ua-cam.com/play/PLqzw97Uv36MmaSbNpNYtEzK8xS6DcDuPc.html
Google "nuclear engineering curriculum" at any of the more prestigious engineering schools, ie MIT, Illinois, Purdue, Michigan etc and that will give you the semester by semester course listing of their respective nuclear engineering curricula.
The "dollie parton curve for reasons that are highly scientific" 😂😂😂😂 that made my night... U could be the first nuclear studied comidien and youll hit hard at the stand up shows 😂
I find it interesting how you're pointing out to all the things that wouldn't happen today because of rules, laws, protocols, etc. in place. However, the primary reason these safety protocols exist today is because of all of these accidents, that claimed a lot of lives and caused a lot of damage.
That’s how things evolve. Americans would be the first in line trying to collect money and blame somebody else for their mistake or for lack of regulations etc. Rules… they are for the other guy… mother nature 1:0 humans…Saturday afternoon matinee😂
I think we kind of have to chalk this cavalier approch to safety to two major factors: 1) The risks weren't always well understood - and even where they were understood, these people hadn't been trained in an environment that drilled the reality of those dangers into them at a deep level. Humans are pretty bad at risk assessment unless it's heavily reinforced. 2) The Manhattan Project was a 'crash' project to develop as superweapon as quickly as possible during the course of the largest conflict the world had ever seen. Hundreds if not thousands of soldiers were dying every day. Thus the projects were looking for results, and results only. Safety was a secondary if not tertiary consideration, and some of the people they'd hired in for them would have been among the least risk-averse in the physics community, much like test-pilots and race car drivers are not known for their reserved driving habits. At this point of course the war was over, and these projects should have been reigned in and restructured to incorporate a much more normal work environment with actual safety in mind - but that wasn't the culture that had created any of this, so it was probably always going to take some harsh lessons of this sort to kick them in the ass and get them to change approach.
Just think about how scary this situation is. You see that flash of light - you know you're a dead man walking at that point. I can't imagine how that feels.
Hey just found this channel a couple days ago and I'm loving the videos! I was thinking maybe you could check out a video about the US making a nuclear powered plane back in the 40-50s, pretty sure Real Engineering has a video on it thats good. Oh also sometimes you edit/cut out the end of a word when your talking and its a little jarring, other than that I'm looking forward to more nuclear themed videos!
Talking about things being less red tape then: The prof who taught me nuclear technology in the early eighties had been one of Fermi's student workforce that piled up the graphite blocks under that stadium in Chicago. He told us an anecdote about when they were looking for a water leak in the plumbing of a university building. They mixed a radioisotope in the water, let it circulate for some time, then flushed with clean water and the went looking for the leak with a Geiger-Müller counter...
One thing about this, when talking about how this would never be allowed to happen like this happen, is the consideration that these very events are exactly why all those strict procedures are in place.
There is an exceptition for fuel enrichment rate in reactors though. Reactors used in submarines and ships also sometimes use highly enriched fuel. The S6W reactor which is a naval reactor used for subs in the US Navy runs 93.5% enriched uranium. As submarines have limited space, naval reactors are hard to service. High enriched fuel will allow the sub to just perform a single fuel rod change during it's whole service time. It has the downside though that prior to it's service you basically need to produce weapons grade uranium unless material from old dismantled nuclear weapons is used.
I've been watching for a while.. just realized i'm not subscribed and have been algorithmically watching D: Great content! I'm a nuclear physics enthusiast with a portable gamma spectrometer, I found a rock that's 300 uSv/hour Do you think that's a lot?
The average background radiation is 2.8 mSv/year in the USA. 300 uSv/hour = 0.3 mSv/hr. This rock could deliver a yearly background radiation dose in 9.3 hours. If a person would be near a source with such activity for a year, person would receive about 2628 mSv additionally on top of background radiation per year. When given at once, a dose of 2.6 Sv is categorized as HIGH by health physicists. If this dose is spread over a year, it will increase one’s chances of getting cancer, genetic abnormalities (for future children). Some radionuclides will decay over a year, and the activity will be reducing, but anyway don’t hang out near this rock. Give it away to a university for studying.
It wasn’t really because of poor regulations that contributed to bad safety practices directly. He’s scientists were the pioneering experts in this field, and so the practices that they followed were of their own design there was no external authority that existed to regulate activities or have any kind of expertise in this field. The other nature fact that contributed to the east, is that 100% of the existence of all of this was classified. As far as anyone outside of the program was concerned, none of this existed and thus it’s extremely hard to regulate somethings that is not supposed to exist in the first place. Incorporating more people into the program to oversee its activities, was a higher security risk than the risk of health and safety violations due to bad actions. This is unfortunately a common side effect in covert operations. You can’t commonly have a high level of officials over seeing them, because it makes them no longer covert.
Critical mass. This is where people started to understand critical mass and how dangerous it was. Louis Slotin is like Stockton Rush on nuclear engineering.
How dangerous? Hell, it's critical mass which brought the idea of an atomic bomb, to begin with. What could be more dangerous than an instant disintegration? I'd say this was were they started to get the idea of the radiation hazard.
I love Kyle Hills nuclear videos, the medical equipment allowed to poison a town, the blue laser through brains and Nuclear experiments are what I listen to at work a lot fo the time.
The movie showed him hiding behind "bricks" of lead, if i remember right, manipulating the "demon core" which was, a sphere of burilium cut in 1/2 sections, with a ..screwdriver. Measuring the levels of alpha? Neutrons coming off of it as he changed the angle? Then there was a noise that caused him to drop the top half into the bottom, causing a semi critical mass. He grabbed it and pulled it off the other one, but it was too late for him. Lethal dose of radiation. At least that is my understanding. Correct me if i am wrong.
They could have done the experiments in a way where prompt criticality wasn't possible, and you know, not have balanced the neutron reflector with a screwdriver and bare hands... I agree that the experiments had to be done, just not that they did it the most reckless way possible.
I read in the book "the secret that exploded" that the guy using the blocks was supposed to have used 1/8th blocks, 1/half blocks and full blocks of reflector. he was supposed to build the reflector with the 1/8ths slowly checking each time on criticality until he had a 1/2 block which he would then replace the 4 1/8th blocks with a half and build up the rest of the block then replace the 4 8ths and 1 half with a whole. i also read the guy didnt do this and began using full blocks each step and slowly loweing the block into place and stopping when criticality got higher. Sad to see the next guy just kept doing the experiment in an almost equally dangerous way with a freaking screwdriver.
One physics point - the damage done by gamma rays is more than simple heat. Because of the high energy, Compton scattering becomes a factor, and this can cause short period catastrophic ionization of any atoms in the way with loosely bound outer electrons, e.g. the iron atoms in your blood. This would be as destructive as simple kinetic collisions with neutrons. When Compton scattering is not a factor, you just have either no interaction, or "knock off" ionization via the photoelectric effect. The scattered gamma rays and downshifted some but successive events happen until the energy has been lowered enough. IOW gamma rays are bad news when they are dense enough.
Learning curves are dangerous. I saw the Kyle Hill video long ago. I hear echos of the early work on some infectious agents. Experiments were only roughly designed and how could they know to design away the danger they did not yet know.
That pit was remelted and used in one of the tests. Since the pit was in critical excursions, it had the unusual effect that the mass/energy conversion was more efficient, ie there were more "generations" of the chain reaction. The reason for using the implosion system in the Pu device is contamination with Pu240, which is self-fissile and leads to pre-detonation, i.e. the number of generations is reduced, the fissile material is "dispersed" below the critical mass density and further reaction is not possible. When unplanned critical excursions occurred, a large part of the Pu240 contaminant was "burned off" and repeated chemical treatment was required to remove the fission products. The final pit had a reduced proportion of Pu240, and during the implosion, the critical density/mass was maintained for a longer time, which resulted in a higher efficiency of the chain reaction compared to the initial mass of the pit
As someone who once lived 20 minutes from Los Alamos Labs, and have know people employed there in more recent times, I'm curious, what likely would have been the outcome if he had not swatted the brick away at that moment? Assuming neither him nor the security guard stopped the reaction, but ran instead. How different would New Mexico be today? I moved farther since, but still only about 400 miles away, Would my current town have been effected? Also, I am very much liking your channel after stumbling into it. Thank you.
It's just a small, unshielded, uncooled reactor that's prompt critical. It would probably melt down rapidly, or thermally expand to the point where it's no longer prompt critical. Even if it stabilized at power levels low enough for passive cooling it would take years to react as much as an actual bomb, so it shouldn't exceed that level of fallout. The military would probably just shoot it or something (an irradiated garden solved a problem with their Co-60 source getting stuck exposed by shooting the rope). Based on other criticality accidents (these are from Wikipedia's list) with long excursion times, it would make the accident worse, but only the people nearby would suffer from it 16 June 1958 criticality incident at Y-12 plant: 20 minute excursion due to uranium collecting in a 55 gallon drum. 3 January 1961 SL1 meltdown: a technician lifts a control rod by hand too far, resulting in prompt criticality, a steam explosion destroying the reactor, a few years of cleanup work, significant radiation exposure to rescue workers, and 3 fatalities due to the explosion. 30 September 1999 Tokaimura nuclear accident: workers deviate from procedures for the production of uranium fuel, leaving a precipitation tank of critical uranium to react for several hours until the water jacket was drained, boric acid was dumped on the tank, and sandbags were put up to allow residents back into the area.
Actually it could end up being like how the "nuclear bonfire" was handled, where you have a team of people practice using custom tools to dismantle and stick the assembly in a shielded box as quickly as possible (there's a video of the rehearsals and actual recovery on this site, and a reaction on this channel, look up "Lia radiological accident").
Tyler repeating ''demon core'' at the start is like one of thoses old japaneses godzilla movie where the camera switches to several people saying ''GODZILLA!'' 😆
could you please give your opinion to kyle's video on the therac-25 ? no one has yet done that......and i and probably others would appreciate if you would.
Heh, Dolly Parton curve. Reminds me of my 7th grade math teacher, Mrs. Johnson... she called improper fractions "dolly parton fractions" because they were top heavy.
'Tickling the tail of a sleeping dragon' isn't accurate at all... It's more like 'playing with an ancient curse tome'... Can kill you and many others on the spot, can just 'curse' you and the people nearby and make you 'rot alive', but may spare you and give you some desired special powers too
Another bit of forgotten history is all of the patent medicines that featured the use of radium In various ways and also all of the people, mostly women, who painted the hands and numbers on wrist watches with radium paint for nighttime viewing not to mention the wearers too. The women were said to wet the tips of their paint brushes on the tongues to bring the hair to a fine point before dipping in the radium paint. Over time they would ingest this radium just like those who had ingested the radium infused medicines.
Perusing the comments, it is especially noteworthy the number of people who see Slotin as a lazy physicist-slob. Yeah, he was still essentially a teenager at heart, but the urgency of the Los Alamos goal was also very pressing. There was a war on, they cut corners and did things expeditiously under great pressure. It is sort of like the bomb disposal expert faced with "Which wire should I cut??!??" as the big LED window was ticking through "00:00:10" and the music was crescendoing a screaming pitch, except that the war was real. College drinking buddies were being shot to death in droves and you are on an extended vacation to scenic New Mexico. "Wasting" time on elaborate safety probably seemed like tempting hell. Yeah, the accident happened after the war (by about five months), but they'd all spent three years in the pot getting hot before last August.
When you compress/implode a plutonium sphere you get a spherical plasma, but what happens in a gun type bomb like little boy? Is the initial plasma a taurus shape? I have always wondered this but there is basically no information on gun type bombs other than little boy and that available info is pretty vague, I guess owing to it only being used in combat and not tested under full scientific observation.
Damn, great review. Had no idea about the "Demon core", happy the nuclear scientists community with people like you deliver this to us rest, like Kyle Hill too, wouldn't know about it otherwise. But it was hard to watch indeed. I can't imagine the pain they went afterwards radiation poisoning and how much pain it was. Would prefer honestly a bullet rather than that to be done.
I worked as a temporary employee in a nuclear power plant during its construction, as a word processing secretary. I think it was about a year before low power tests were started around 1985 or so (a year or so, during low power testing, I worked as a radiologically controlled area monitor, again as a temp). I was told that no-one in the office areas needed a badge to measure their cumulative radiation as these areas were monitored some other way to make sure the level was safe. However when I got to my work table in at my office space, I noticed a bunch of "gas masks" hanging right there in the office space. They were hanging over a sink I think, and near by was coffee pot with brewed coffee in it, and a coffee cup, which had coffee statins inside. "Would you like some coffee" someone asked me." Sure I said. Where can I find a cup. She pointed to the cup. I said "is that a clean cup?" and she replied yes it's clean. I wasn't particular worried about getting any sort of infection from a cup that wasn't not thoroughly cleaned, so I poured some coffee into the cup. It was this most horrid coffee I ever tasted. But I needed caffeine to do my job. So I drank it. Then I began worry, was those masks being used to filter out radioactive particles from the air? If so, why were they in the office area, and why near the coffee pot? It seemed a bit too lackadaisical to have gas masks in the office area, even if they were just to filter out dust from materials that were not radioactive. I also wondered why they were hiring many temp workers instead of permanent employees. Was it because the OSHA regulations for exposure to ionizing radiation for short term workers were less stringent? I also found it disturbing that while I was stationed at the door to the RCA, and was given a radiation counter, I was not given a badge to measure my cumulative dose. Speaking about lackadaisical procedures, with the reactor cooking at 5% capacity, and large pipes all over the place having what I thought must be hot water running through them, the place was very very noisy. There were signs all over saying hearing protectors are supplied for your use as the noise level hear is at or near the level at which it can damage your hearing. I found the noise to be painful. But I did not see anyone wearing hearing any of the available hearing protectors! While I don't mind wearing hearing protectors for an hour or so, wearing them 8 hours a day would give me a headache just from the pressure against the side of my head.
What was Slotin trying to achieve, at what point would he stopped lowering the sphere? He must have known that he had to avoid supercriticality. It's like igniting a firecracker without a fuse, and trying to recognize the point of ignition right in time to pull the match away.
Yeah though peoples risk tolerance varies a lot and in a lot of cases you kind of do need people who are willing when something is new to test things and see what happens. Reminds me of the wild stuff they got up to in military weapons testing at this time where they would do stuff like shoot each other to test protective vests out and the likes. Which is a little too spicy for people in the modern day.
He did know better. He chose to ignore all the protocols that were in place. He was so arrogant and his success(12 times he did the same thing)that he kept doing it.
I remember seeing a movie about the development of Fat Man and Little Boy many years ago that showed the second accident, when the screwdriver slipped and he tossed everyone chalk to mark where they were standing in the room. I don’t remember it mentioning the prior accident, but it was clearly shown that he knew what his fate would be as a result of his proximity to the core
This reminds me of the period in the 1800s when the progress towards isolating elemental fluorine could be followed via the obituaries column of the newspapers.
Question sir?? Are these reactions of the scientists continually doing more and more dangerous things, because back then they knew what could happen, or are they based on our updated knowledge of today?
My perception is that the most publicly documented criticality tragedy is the Tokaimura incident, 1999. They ended up keeping the poor victim alive to do experiments on him. It was horrible. Of course, I'm sure nuclear militaries have worse tragedies that have not been discussed much.
The Cold War of course was a reason why even allies did not trust each other, for the fear that the other side would get useful information not only about what was possible, but what you were doing.
I do wish he and others would be more specific. Just going critical doesn't create a bomb. Neither does going supercritical. Or prompt critical. Prompt supercritical is required, a state of unimaginably rapid increase in reactivity. Anything less and the core will just blow apart without a proper explosion. Bombs have to force this to happen, which is why a powerplant physically cannot, even if using - hypothetically - more enriched fuel, create an nuclear bomb.
With all the nuclear incidents/disasters out there, I notice that a blue light is typically the described visible light that is emitted from highly radioactive content, why is the colour blue? I figured with where Gamma rays are on the wave spectrum that the emitted light should be violet as the violet wavelength is closer to the gamma wavelength than blue is. (probably a silly question but I want to know).
Short version, it's the sonic boom of radiation. Cherenkov radiation in specific, go look it up if you want the full details. I probably got the spelling wrong but it should be close enough.
The radiation itself is invisible, but as the excited particles hit air they fission atoms in the air/water surrounding them causing a microseconds blue flash... a subcritical assembly is simply not releasing that many particles, so the flashes are only visible to very sensitive detectors, but once the assembly goes hot there are enough reactions that it is visible to the naked eye. Somewhere like a spent fuel pool, where the items are hot due to residual reactiveness, the blue glow is the warning that you would seriously not enjoy being there, but it is not a safe warning measure because the light comes well after dangerous levels of radioactivity. Consider the Lia Incident for details of where that blue glow was not present, and it was still VERY lethal, or any of the half dozen cobalt 30 accidents.
@@leechowning8728 Cherenkov radiation has nothing to do with fission products. It's caused by charged particles moving through a medium faster than light (air and water are not vacuum). It's an excitation and the blue glow is bleeding off the excitation.
Something I think they didn't really understand at that point was that even low levels of radiation can be harmful if you're around it long enough. The demon core wasn't an on/off thing, it was always emitting SOME radiation. It's like being around a bonfire vs being in a burning building. The smoke is bad for you regardless, but the more of it there is, the faster it's going to kill ya.
Of course, this wouldn't be allowed today and of course today we look at this and see "bad idea" written all over it, but that is because these incidents have already happened and we have learned from those mistakes. Before they were made however, while a disaster could have been predicted, we simply didn't know what would happen and the only real way to find out was to test it, and then find out the hard way.
I remember a long time ago reading a sci-fi fantasy book where a guy made a crude nuke in a granite mountain by boring a hole into the side of it. Cant remember if he had a metal cylinder or not to line the hole. Somehow had plutonium disc, enriched uranium disc or something then a small explosive charge in that order. Sealed it up and deleted part of the mountain for some reason. Cannot remember the name of that book, but as a kid I was like that seems way too easy. It was my first exposure to nuclear and nuclear weaponry. I was pretty young and thought it was really cool, albeit crude that you could do that and make it work. Of course that was before I learned how hard it is to get plutonium and weapons grade uranium. Ill have to search for that book to get the title, or if someone knows the book I am talking about. I'm really bad at remembering author names and titles lol plus this was back in the 90s and I was like 10 years old or younger. And that is the only thing I remember from the book lol. 😋 But it did get me more engaged into science. As always love your content!
sounds remotely similar to the nightlord series, which the titular character Halar/Eric creates a nuclear .....power source not a reactor but... its hard to explain.
the gun-type weapon used on Hiroshima is similar to what you describe, simply one piece of enriched uranium shot at another by an explosive charge to form a combined critical mass. the efficiency is much lower than more advanced implosion devices, but it's by far the simplest and most reliable way to design a weapon.
Would the experiments even be valid given the time constant of the delayed neutrons? They could have assembled a supercritical geometry but not have a valid instrument response because they adjust the geometry faster than the system could respond. Or were they manipulating a core that was already in the delayed critical regime, looking for the prompt critical dragon? Are there currently any 'Approach to Criticality ' experiments being done? Jon
I believe there are current 'approach to criticality' experiments, hopefully with much more stringent controls and safety procedures: organizations.lanl.gov/ncerc/
Great commentary, mister engineer. Amazing how we can't blame this on ignorance, for as soon as they achieved criticality, they immediately knew what they've done.
"Not allowed" and "under no circumstances" keep being brought up... I wonder... What if we established a "Cowboy Science Lab" somewhere _even more remote_ than Los Alamos? Somewhere in East Jesus, Alaska; somewhere where the only rule is "never stop documenting what you do, ever," and safety is "your business and nobody else's." ...
Not only killing those in the room, what would have happened to the entire Manhattan project if either of these people had not been able to interrupt the prompt critical reaction? Could the entire crew of scientists and engineers have been wiped out in one shot?
"regulations are written in blood" -
My safety manager
That is why they're not the sanitary manager.
Lol 😂@@StorymasterQ
You stole this from somewhere
I can _kind of_ understand the first accident. It was the very early days of a new technology; the regulations hadn't yet been written; society was much less safety-conscious in general (fun fact: when Ford began offering seat belts as a option in 1955, fewer than 2% of buyers opted for them).
What I can't fathom is watching your friend and colleague die a preventable, slow, horrific death, then going on to do something even _more_ senselessly dangerous-and putting seven other people at risk! It's simply unthinkable.
My father, a U.S. Navy aviator, piloted an aircraft loaded with scientists and instruments at the Castle Bravo nuclear weapon test. 6 megatons were expected; we got 15. Turns out there's a difference between Lithium-6 and Lithium-7. Turns out that extra neutron matters. And lots of folks in the test got a lot more irradiated than expected.
He died at age 49 (when I was very young) with half a dozen kinds of cancer. Lung cancer, kidney cancer, melanoma, leukemia, CRC, pancreatic.
VA tried to say it wasn't service related to deny benefits.
We owe so much to the early pioneers that risked their lives, often unknowingly, for all the knowledge we've gained from their sacrifices. The government should recognize them all retroactively and compensate families that had loved ones become ill and die from exposure to toxic or radioactive materials while working for or serving our country. Especially for those who became terminally ill and were told it wasn't related to their service and denied any recognition or benefits. Even today our veterans still aren't being taken care of the way they deserve to be.
It's "never" service related....
I'm sure he is happy to give his life so his son could be a furry
good to know the VA has ALWAYS been as useless. Makes me feel like its a little less personal
@kristianniss5201 zero empathy moment. I bet you'd be the kind of person to deny benefits to veteran families who lost their loved ones due to their time in service
1940s Scientists: “Ever wonder what would happen if we edge a nuclear weapon?” 😂
God damn you! Its too early to choke on my coffee! Good one!
spectacular failure of a no nut nuclear
Man I know this comment is old but daaamn it's literally what they did 🤣
@@thefridge7335 Yea they did! 😅
If you improperly edge the bomb it gona blow
Tip: Brazilians love when people talk about their country I recommend doing a video about the caesium 137 acident in Goiania
seconding this!
whomst summoned the brazillians
I also support this. It is a heart breaking tragedy.
I so knew that's where you were going with that! ( I've seen entirely too many of Kyle's videos, I guess.) 😂
Come to brazil is one of my favorite memes. Much love to the Brazilians
The "flat-head screwdriver incident" is directly referenced in a mid-game level in the civil-engineering-'em-up _INFRA._ You find a _suspiciously familiar_ half-dome and sphere setup in a certain spoilery area, along with a written note that ends with "I don't care how good your 'prestidigitation' is. If that reflector locks in, WE'RE ALL DEAD!". Being a video game, you can, ahem, do the obvious thing (complete with blinding flash of white as Mark dies), and get an achievement for it!
I was lucky to read an article in "The New Treasury of Science" as a kid called "The Death of Louis Slotin". This was a good thing for a science kid to read. It not only gave me a healthy respect for radiation, but tended to moderate all the dangerous things I was doing with chemistry and electricity that could have harmed be the old fashioned way :) Thanks for the video!
As a licensed electrician and avid organic chemistry fan,(as well as a nerd with everything science, all aspects) I can say that some of the incidents I had as a young guy, while minor, helped keep from from making sincerely bad mistakes when older !
Kyle hill and Plainly Difficult are great channels with nuclear disaster content to react to
an autistic arrangement
Yes plz
Here for the PD comment!
Great review of an equally well done Kyle Hill video. His Half-life series is very well researched and a pleasure to watch. You might want to do a few more of them. I really like how you explain in a clear, concise manner what would be done today, and how experiments like this would not be even almost allowed, full stop. Your channel has fast become one of my favourites because of it👍
Thanks so much! I really appreciate it!
My Father-in-Law was a chemist that worked on the Manhatten Project. He helped design the implosion explosives that detonated Fat man. He had so many awesome stories about his time there. He told me of one of his visits to a neuclear reactor where he viewed the core from a catwalk above and could see the blue glow of the reaction below. He passed form liver cancer which no doubt was from his exposure at Los Alamos.
That peer checking and oversight is because of incidents like this. Rules and laws are made because someone did something that necessitated it. Also. My grandfather was at Bikini and was on deck to witness several tests. They gave them welding goggles as their only PPE. He died of a weird form of Parkinson's at 79, which is weird because it not only doesn't run in the family, but most of his brothers and sisters lived into their 90s and 100s.
His Parkinson's then was probably radiation-caused.
@@exxor9108 That's the assumption. That and/or defoliants used at guadalcanal and experimental firefighting chemicals in the CDF... or aboard ships. He was exposed to a lot of crazy shit in the 50s and 60s.
Oh wow you don’t say. I thought they threw out that anecdote for no reason as I couldn’t have imagined a connection. Thanks for the enlightenment
@@MysteriousStranger50 My dad has the welding goggles my grandfather wore for the tests.
Bikini Atoll. I am so ashamed of my fellow man. It's exactly like these witnesses were actually lab rats....
The disappointed "why?" around 14:20 was just so perfect lol. The sheer audacity of the safety disregards were just too much.
The accident is shown in the movie Fat Man and Little Boy. It stars Paul Newman and John Cusack.
Btw, 40+ years ago I attended the only high school in America with a radiation lab which had a Cobalt source. Teacher was a physicist who worked at Oakridge during the summer building bombs and taught physics during the school year. Her name was Barbara Reed. High School is Riverview high School in Sarasota. She convinced the school board to have the lab installed so they can study the effects of phosphate mining which is big in that area and what it was doing to the environment because when you dig up phosphate, you dig up the whole uranium decay chain.
At the time she told us that there had not been any American civilian deaths from radioactive material. But one day she did a lecture on the accidents that happened to government contractors. With slides. Anyway, because of her in that class I decided to become a radiographer and I was one for 25 years.
That's really cool. You know, as far as she knew, there probably weren't any civil deaths due to radiation. The demon core and other Los Alamos deaths due to radiation were classified into... I think the 70's or 80's.
They didn't build bombs at Oak Ridge. They enriched uranium there. The details of Daghlian and Slotin's deaths were kept secret for a long time after they happened in 46-47. Cool memories.
@@puncheex2 Yes I understand that they didn't actually build bombs there, it was urnium production. This was back during the Cold war. I also met another scientist that had worked at oak ridge. That's when I became an x-ray tech and worked at a doctor's office. We were both talking about being exposed to radiation is how that came up when I was x-raying his knees.
I worked at Los Alamos from 1993 to 2000 for the Dept. of Energy as a nuclear engineer doing safety oversight. One of my assigned areas was TA-18, the Critical Experiments Area, or as it was referred to in the video, Pajarito Site. At about 11 minutes into the video a comment is made that experiments involving prompt criticality are not controllable and would not work, which is not entirely true. During my time there, multiple experiments were completed at prompt critical using the Godiva IV critical assembly. I observed several of them. The Godiva assembly used a safety block that was ejected from the machine by the energy shock wave created when the machine went prompt critical. Since then, the critical experiments facility has been moved to the Nevada National Security Site (previously known at the Nevada Test Site). Obviously, all experiments involving criticality are now done remotely.
iirc the main advantage to using water as a reflector and moderator is that, when the core gets too hot, the water boils and evaporates, meaning it doesn't reflect or moderate anymore, and stops the reaction from going out of control.
As long as the reactor can hold the pressure :/
Engineer 1: "Hey, want to see something cool?"
Engineer 2: "Yeh, wait..... is that a screwdriver holding a top metal dish slightly ajar? Is that a core in the middle?"
Engineer 1: "Yup, now the only thing keeping us from getting irradiated and killed is that screwdriver. Hope no one knocks it over.... Oh crap"
Engineer 2: "Congrats you just doomed us in the room"
Engineer 1: "Well... That does it." 🤷
Hey, want to see a joke written by a 7 year old?
I was in grad school in the late 1980s and had a professor that had work at Los Alamos starting in 1945. He used to tell us all these stories of stuff going on there. Like how they used to align particle accelerator beams by sticking their head into the beam and adjusting ito to get the most light from scintillations from the fluid in their eyes
He never brought up the subject of that mysterious object that crashed near the Trinity site in 1945, did he? Of course, not, he probably never even heard of it. Jacques Vallée wrote a book, recently, about it. It's pretty interesting.
Eyeballing level master xD
There was a Russian physicist that got zapped in the head by a full strength particle beam because his colleagues didn't know he was working on it at the time. But maybe our host has covered that? Didn't kill him, but it did something to the nerves in his face, like a permanent botox?
Fun fact: The Bikini Atoll mentioned at timestamp 20:18 is where Sponge Bob takes place.
Depressing fact: Bikini Atoll was populated, and the residents were forcefully relocated for the tests to an island, but then they started starving to death and were then relocated again.
Afterwards they were placed back on Bikini Atoll, but then later when it was noticed the residents carried abnormal amounts of Caesium-137 and the well water carried abnormal counts of Strontium-90 they were evacuated and subsequently lost their homes forever. The Bikini Atoll is now only visited by divers and scientists.
Also strangely enough is where the name for bikini swimwear came from.
Isn't the Bikini Atoll the most nuked place on earth too? I'm sure it held some kind of gruesome title like that.
@@Bassalicious A quick google search tells me the most nuked place is Semipalatinsk, but maybe bikini atoll has another situation going on that I don't know about.
@@autohmae I was wondering why it shared that name, though I did not expect the bikini to be named after the island.
@@Bassalicious It might have been known as the most nuked place on earth by Westerners before the fall of the USSR, so Semipalatinsk was probably not well known at the time.
Kyle Hill has a t-shirt, poster, and coffee cup you can buy that hss a diagram drawing of the scientists standing in thier respectively positions around the Demon Core prior to it going critical with the caption "Go ahead, f*ck with it. See what happens!"😊
The recognition of cancers caused by radiation exposure go back to 1902. After WWII, and with names like Feynman, and Enrico Fermi involved in these projects, they most definitely knew about the possible consequences.
Indeed. They didn't treat the risk like we would today because their mindset was different. Their primary concerns were things like the end of the world as we know it, not maybe getting cancer in 20 years. They all knew guys who had gone into greater danger, and guys who hadn't come back.
Hello! I'm newly subscribed to this channel, but I was wondering if you had any plans to make videos explaining some nuclear engineering concepts? I'm currently a college sophomore, but I plan on majoring in nuclear engineering after I get my gen-ed's out of the way and transfer.
Maybe just a video explaining what classes you had to take and why they're relevant or something like that. I think a lot of people would be interested - or at least - curious about that.
Loving the channel so far!
Have fun on your journey into nuclear engineering!
I’ve done a few shorts on some nuclear engineering concepts and misconceptions:
Nuclear Engineer Explains
ua-cam.com/play/PLqzw97Uv36MmaSbNpNYtEzK8xS6DcDuPc.html
Google "nuclear engineering curriculum" at any of the more prestigious engineering schools, ie MIT, Illinois, Purdue, Michigan etc and that will give you the semester by semester course listing of their respective nuclear engineering curricula.
That’s the thing. We DID know about. The second guy that cause a death event knew exactly.
Saying we didn’t is incorrect.
The "dollie parton curve for reasons that are highly scientific" 😂😂😂😂 that made my night... U could be the first nuclear studied comidien and youll hit hard at the stand up shows 😂
I find it interesting how you're pointing out to all the things that wouldn't happen today because of rules, laws, protocols, etc. in place.
However, the primary reason these safety protocols exist today is because of all of these accidents, that claimed a lot of lives and caused a lot of damage.
Not to mention that the entity who would come after you for violating the regulations now, was in this case the entity directing these projects.
Regulations are often written in blood, as the saying goes.
That’s how things evolve. Americans would be the first in line trying to collect money and blame somebody else for their mistake or for lack of regulations etc. Rules… they are for the other guy… mother nature 1:0 humans…Saturday afternoon matinee😂
Your videos are very insightful, I love nuclear physics and always glad to find more channels with that kind of content. I subbed buddy!
I think we kind of have to chalk this cavalier approch to safety to two major factors:
1) The risks weren't always well understood - and even where they were understood, these people hadn't been trained in an environment that drilled the reality of those dangers into them at a deep level. Humans are pretty bad at risk assessment unless it's heavily reinforced.
2) The Manhattan Project was a 'crash' project to develop as superweapon as quickly as possible during the course of the largest conflict the world had ever seen. Hundreds if not thousands of soldiers were dying every day. Thus the projects were looking for results, and results only. Safety was a secondary if not tertiary consideration, and some of the people they'd hired in for them would have been among the least risk-averse in the physics community, much like test-pilots and race car drivers are not known for their reserved driving habits.
At this point of course the war was over, and these projects should have been reigned in and restructured to incorporate a much more normal work environment with actual safety in mind - but that wasn't the culture that had created any of this, so it was probably always going to take some harsh lessons of this sort to kick them in the ass and get them to change approach.
Classic case of "The more you fuck around, the more your gonna find out!" sadly
Just think about how scary this situation is. You see that flash of light - you know you're a dead man walking at that point. I can't imagine how that feels.
Hey just found this channel a couple days ago and I'm loving the videos! I was thinking maybe you could check out a video about the US making a nuclear powered plane back in the 40-50s, pretty sure Real Engineering has a video on it thats good. Oh also sometimes you edit/cut out the end of a word when your talking and its a little jarring, other than that I'm looking forward to more nuclear themed videos!
Welcome aboard! Thanks for the suggestion!
13:35 bro isn’t just dancing with death this guys break dancing with death
Talking about things being less red tape then: The prof who taught me nuclear technology in the early eighties had been one of Fermi's student workforce that piled up the graphite blocks under that stadium in Chicago. He told us an anecdote about when they were looking for a water leak in the plumbing of a university building. They mixed a radioisotope in the water, let it circulate for some time, then flushed with clean water and the went looking for the leak with a Geiger-Müller counter...
One thing about this, when talking about how this would never be allowed to happen like this happen, is the consideration that these very events are exactly why all those strict procedures are in place.
12:58 can we take a moment to appreciate that the guy sticking a screwdriver in a slot is called Slotin
There is an exceptition for fuel enrichment rate in reactors though. Reactors used in submarines and ships also sometimes use highly enriched fuel. The S6W reactor which is a naval reactor used for subs in the US Navy runs 93.5% enriched uranium. As submarines have limited space, naval reactors are hard to service. High enriched fuel will allow the sub to just perform a single fuel rod change during it's whole service time. It has the downside though that prior to it's service you basically need to produce weapons grade uranium unless material from old dismantled nuclear weapons is used.
I've been watching for a while.. just realized i'm not subscribed and have been algorithmically watching D:
Great content! I'm a nuclear physics enthusiast with a portable gamma spectrometer, I found a rock that's 300 uSv/hour
Do you think that's a lot?
The average background radiation is 2.8 mSv/year in the USA. 300 uSv/hour = 0.3 mSv/hr.
This rock could deliver a yearly background radiation dose in 9.3 hours.
If a person would be near a source with such activity for a year, person would receive about 2628 mSv additionally on top of background radiation per year. When given at once, a dose of 2.6 Sv is categorized as HIGH by health physicists. If this dose is spread over a year, it will increase one’s chances of getting cancer, genetic abnormalities (for future children).
Some radionuclides will decay over a year, and the activity will be reducing, but anyway don’t hang out near this rock. Give it away to a university for studying.
It wasn’t really because of poor regulations that contributed to bad safety practices directly. He’s scientists were the pioneering experts in this field, and so the practices that they followed were of their own design there was no external authority that existed to regulate activities or have any kind of expertise in this field. The other nature fact that contributed to the east, is that 100% of the existence of all of this was classified. As far as anyone outside of the program was concerned, none of this existed and thus it’s extremely hard to regulate somethings that is not supposed to exist in the first place. Incorporating more people into the program to oversee its activities, was a higher security risk than the risk of health and safety violations due to bad actions. This is unfortunately a common side effect in covert operations. You can’t commonly have a high level of officials over seeing them, because it makes them no longer covert.
Also, there was a war on. They worked 6-7 days a week, 12-16 hours a day to get to where they were. Many felt there was simply no time for protocols.
@@puncheex2 wasn't this afterwards though?
Its the "well that's it" that gets me everytime.
Critical mass. This is where people started to understand critical mass and how dangerous it was.
Louis Slotin is like Stockton Rush on nuclear engineering.
How dangerous? Hell, it's critical mass which brought the idea of an atomic bomb, to begin with. What could be more dangerous than an instant disintegration?
I'd say this was were they started to get the idea of the radiation hazard.
I love Kyle Hills nuclear videos, the medical equipment allowed to poison a town, the blue laser through brains and Nuclear experiments are what I listen to at work a lot fo the time.
The movie showed him hiding behind "bricks" of lead, if i remember right, manipulating the "demon core" which was, a sphere of burilium cut in 1/2 sections, with a ..screwdriver. Measuring the levels of alpha? Neutrons coming off of it as he changed the angle? Then there was a noise that caused him to drop the top half into the bottom, causing a semi critical mass. He grabbed it and pulled it off the other one, but it was too late for him. Lethal dose of radiation. At least that is my understanding. Correct me if i am wrong.
thank you for immediately pointing out the difference between a reactor and a bomb.
I've lost count of how many people I tried to explain this to.
They couldn’t have a “shut down margin” before defining the margin, which is was only possible after these criticality experiments.
They could have done the experiments in a way where prompt criticality wasn't possible, and you know, not have balanced the neutron reflector with a screwdriver and bare hands... I agree that the experiments had to be done, just not that they did it the most reckless way possible.
I read in the book "the secret that exploded" that the guy using the blocks was supposed to have used 1/8th blocks, 1/half blocks and full blocks of reflector. he was supposed to build the reflector with the 1/8ths slowly checking each time on criticality until he had a 1/2 block which he would then replace the 4 1/8th blocks with a half and build up the rest of the block then replace the 4 8ths and 1 half with a whole. i also read the guy didnt do this and began using full blocks each step and slowly loweing the block into place and stopping when criticality got higher.
Sad to see the next guy just kept doing the experiment in an almost equally dangerous way with a freaking screwdriver.
“Tickling the tail of a sleeping dragon” love that quote. So true too
One physics point - the damage done by gamma rays is more than simple heat. Because of the high energy, Compton scattering becomes a factor, and this can cause short period catastrophic ionization of any atoms in the way with loosely bound outer electrons, e.g. the iron atoms in your blood. This would be as destructive as simple kinetic collisions with neutrons. When Compton scattering is not a factor, you just have either no interaction, or "knock off" ionization via the photoelectric effect. The scattered gamma rays and downshifted some but successive events happen until the energy has been lowered enough. IOW gamma rays are bad news when they are dense enough.
Learning curves are dangerous. I saw the Kyle Hill video long ago. I hear echos of the early work on some infectious agents. Experiments were only roughly designed and how could they know to design away the danger they did not yet know.
That pit was remelted and used in one of the tests. Since the pit was in critical excursions, it had the unusual effect that the mass/energy conversion was more efficient, ie there were more "generations" of the chain reaction. The reason for using the implosion system in the Pu device is contamination with Pu240, which is self-fissile and leads to pre-detonation, i.e. the number of generations is reduced, the fissile material is "dispersed" below the critical mass density and further reaction is not possible. When unplanned critical excursions occurred, a large part of the Pu240 contaminant was "burned off" and repeated chemical treatment was required to remove the fission products. The final pit had a reduced proportion of Pu240, and during the implosion, the critical density/mass was maintained for a longer time, which resulted in a higher efficiency of the chain reaction compared to the initial mass of the pit
As someone who once lived 20 minutes from Los Alamos Labs, and have know people employed there in more recent times, I'm curious, what likely would have been the outcome if he had not swatted the brick away at that moment? Assuming neither him nor the security guard stopped the reaction, but ran instead. How different would New Mexico be today? I moved farther since, but still only about 400 miles away, Would my current town have been effected?
Also, I am very much liking your channel after stumbling into it. Thank you.
It's just a small, unshielded, uncooled reactor that's prompt critical. It would probably melt down rapidly, or thermally expand to the point where it's no longer prompt critical. Even if it stabilized at power levels low enough for passive cooling it would take years to react as much as an actual bomb, so it shouldn't exceed that level of fallout. The military would probably just shoot it or something (an irradiated garden solved a problem with their Co-60 source getting stuck exposed by shooting the rope).
Based on other criticality accidents (these are from Wikipedia's list) with long excursion times, it would make the accident worse, but only the people nearby would suffer from it
16 June 1958 criticality incident at Y-12 plant: 20 minute excursion due to uranium collecting in a 55 gallon drum.
3 January 1961 SL1 meltdown: a technician lifts a control rod by hand too far, resulting in prompt criticality, a steam explosion destroying the reactor, a few years of cleanup work, significant radiation exposure to rescue workers, and 3 fatalities due to the explosion.
30 September 1999 Tokaimura nuclear accident: workers deviate from procedures for the production of uranium fuel, leaving a precipitation tank of critical uranium to react for several hours until the water jacket was drained, boric acid was dumped on the tank, and sandbags were put up to allow residents back into the area.
Actually it could end up being like how the "nuclear bonfire" was handled, where you have a team of people practice using custom tools to dismantle and stick the assembly in a shielded box as quickly as possible (there's a video of the rehearsals and actual recovery on this site, and a reaction on this channel, look up "Lia radiological accident").
The core would have melted and lost its spherical integrity, stopping the reaction after perhaps a minute or two of very high radiation.
Slavin told everyone to mark their position, a true scientist!
I'd recommend you watch the Wendigoon video about the most radiactive man, it's great and really shows the effect radiation has on a man.
Plainly Difficult did a whole bunch of vids on various nuclear accidents and are really well done. Please check some of his out and react.
It isn't that nobody knew that these things could go wrong. They were warned multiple times, and they still went ahead and did it.
Tyler repeating ''demon core'' at the start is like one of thoses old japaneses godzilla movie where the camera switches to several people saying ''GODZILLA!'' 😆
I cannot begin to imagine how horrific and painful it would be to die by radiation sickness. Must be one of the absolute worst ways to go.
could you please give your opinion to kyle's video on the therac-25 ? no one has yet done that......and i and probably others would appreciate if you would.
The software one?
@@Dreron yeah, that one. its a good video........and no one ever reacted to it......weird.
@@DrYu-jf6tb
It's a concrete example on how much software testing and audit is really needed. A bleak one, to be sure, but as valid as it gets.
Heh, Dolly Parton curve. Reminds me of my 7th grade math teacher, Mrs. Johnson... she called improper fractions "dolly parton fractions" because they were top heavy.
A lot of those Los Alamos guys, including Feynman got life shortening doses of radiation, most died prematurely of cancer.
13:45 "B. R. A. S. H. Huh. That's a funny way to spell "stupid"..."
'Tickling the tail of a sleeping dragon' isn't accurate at all... It's more like 'playing with an ancient curse tome'... Can kill you and many others on the spot, can just 'curse' you and the people nearby and make you 'rot alive', but may spare you and give you some desired special powers too
Loved the video!
Another bit of forgotten history is all of the patent medicines that featured the use of radium In various ways and also all of the people, mostly women, who painted the hands and numbers on wrist watches with radium paint for nighttime viewing not to mention the wearers too. The women were said to wet the tips of their paint brushes on the tongues to bring the hair to a fine point before dipping in the radium paint. Over time they would ingest this radium just like those who had ingested the radium infused medicines.
Perusing the comments, it is especially noteworthy the number of people who see Slotin as a lazy physicist-slob. Yeah, he was still essentially a teenager at heart, but the urgency of the Los Alamos goal was also very pressing. There was a war on, they cut corners and did things expeditiously under great pressure. It is sort of like the bomb disposal expert faced with "Which wire should I cut??!??" as the big LED window was ticking through "00:00:10" and the music was crescendoing a screaming pitch, except that the war was real. College drinking buddies were being shot to death in droves and you are on an extended vacation to scenic New Mexico. "Wasting" time on elaborate safety probably seemed like tempting hell. Yeah, the accident happened after the war (by about five months), but they'd all spent three years in the pot getting hot before last August.
The crazy Egos of these brilliant men baffles me.
When you compress/implode a plutonium sphere you get a spherical plasma, but what happens in a gun type bomb like little boy? Is the initial plasma a taurus shape? I have always wondered this but there is basically no information on gun type bombs other than little boy and that available info is pretty vague, I guess owing to it only being used in combat and not tested under full scientific observation.
Tyler: [lists off safety procedures we have now]
Video: [lists off reasons why we have these safety procedures now]
Damn, great review. Had no idea about the "Demon core", happy the nuclear scientists community with people like you deliver this to us rest, like Kyle Hill too, wouldn't know about it otherwise.
But it was hard to watch indeed. I can't imagine the pain they went afterwards radiation poisoning and how much pain it was. Would prefer honestly a bullet rather than that to be done.
I worked as a temporary employee in a nuclear power plant during its construction, as a word processing secretary. I think it was about a year before low power tests were started around 1985 or so (a year or so, during low power testing, I worked as a radiologically controlled area monitor, again as a temp). I was told that no-one in the office areas needed a badge to measure their cumulative radiation as these areas were monitored some other way to make sure the level was safe. However when I got to my work table in at my office space, I noticed a bunch of "gas masks" hanging right there in the office space. They were hanging over a sink I think, and near by was coffee pot with brewed coffee in it, and a coffee cup, which had coffee statins inside. "Would you like some coffee" someone asked me." Sure I said. Where can I find a cup. She pointed to the cup. I said "is that a clean cup?" and she replied yes it's clean. I wasn't particular worried about getting any sort of infection from a cup that wasn't not thoroughly cleaned, so I poured some coffee into the cup. It was this most horrid coffee I ever tasted. But I needed caffeine to do my job. So I drank it. Then I began worry, was those masks being used to filter out radioactive particles from the air? If so, why were they in the office area, and why near the coffee pot? It seemed a bit too lackadaisical to have gas masks in the office area, even if they were just to filter out dust from materials that were not radioactive. I also wondered why they were hiring many temp workers instead of permanent employees. Was it because the OSHA regulations for exposure to ionizing radiation for short term workers were less stringent? I also found it disturbing that while I was stationed at the door to the RCA, and was given a radiation counter, I was not given a badge to measure my cumulative dose. Speaking about lackadaisical procedures, with the reactor cooking at 5% capacity, and large pipes all over the place having what I thought must be hot water running through them, the place was very very noisy. There were signs all over saying hearing protectors are supplied for your use as the noise level hear is at or near the level at which it can damage your hearing. I found the noise to be painful. But I did not see anyone wearing hearing any of the available hearing protectors! While I don't mind wearing hearing protectors for an hour or so, wearing them 8 hours a day would give me a headache just from the pressure against the side of my head.
What was Slotin trying to achieve, at what point would he stopped lowering the sphere? He must have known that he had to avoid supercriticality. It's like igniting a firecracker without a fuse, and trying to recognize the point of ignition right in time to pull the match away.
Worth emphasizing that this was catastrophically stupid even at the time. He had to have known better.
Yeah though peoples risk tolerance varies a lot and in a lot of cases you kind of do need people who are willing when something is new to test things and see what happens. Reminds me of the wild stuff they got up to in military weapons testing at this time where they would do stuff like shoot each other to test protective vests out and the likes. Which is a little too spicy for people in the modern day.
He did know better. He chose to ignore all the protocols that were in place. He was so arrogant and his success(12 times he did the same thing)that he kept doing it.
I remember seeing a movie about the development of Fat Man and Little Boy many years ago that showed the second accident, when the screwdriver slipped and he tossed everyone chalk to mark where they were standing in the room. I don’t remember it mentioning the prior accident, but it was clearly shown that he knew what his fate would be as a result of his proximity to the core
This reminds me of the period in the 1800s when the progress towards isolating elemental fluorine could be followed via the obituaries column of the newspapers.
Question sir?? Are these reactions of the scientists continually doing more and more dangerous things, because back then they knew what could happen, or are they based on our updated knowledge of today?
2:39 As someone from San Diego resident, we call a particular nuclear power plant the “Dolly Parton Monument”
12:45 A "safe distance" would involve a hell of a long screwdriver...
If I can suggest a video I would highly suggest the long but really good video by Emplemon "There may never be a man as powerful as Stanislav Petrov"
The “core” in a weapon is called the “physics Package”
Really enjoy your videos. Thank You👍
Glad you like them!
@@tfolsenuclearso exited to see you growing so quickly
They were a bunch of "nuclear cowboys" back then.
With the Deaths from that incident countless more lives were saved.
Their Sacrifices were not in vain and will always be remembered
Bro, I'm loving these videos
My perception is that the most publicly documented criticality tragedy is the Tokaimura incident, 1999. They ended up keeping the poor victim alive to do experiments on him. It was horrible. Of course, I'm sure nuclear militaries have worse tragedies that have not been discussed much.
The Cold War of course was a reason why even allies did not trust each other, for the fear that the other side would get useful information not only about what was possible, but what you were doing.
I do wish he and others would be more specific. Just going critical doesn't create a bomb. Neither does going supercritical. Or prompt critical. Prompt supercritical is required, a state of unimaginably rapid increase in reactivity. Anything less and the core will just blow apart without a proper explosion. Bombs have to force this to happen, which is why a powerplant physically cannot, even if using - hypothetically - more enriched fuel, create an nuclear bomb.
If you've found this one interesting I can recommend the whole Series of Half-Life Histories by Kyle Hill of which this video was the first.
With all the nuclear incidents/disasters out there, I notice that a blue light is typically the described visible light that is emitted from highly radioactive content, why is the colour blue? I figured with where Gamma rays are on the wave spectrum that the emitted light should be violet as the violet wavelength is closer to the gamma wavelength than blue is. (probably a silly question but I want to know).
Short version, it's the sonic boom of radiation. Cherenkov radiation in specific, go look it up if you want the full details. I probably got the spelling wrong but it should be close enough.
The radiation itself is invisible, but as the excited particles hit air they fission atoms in the air/water surrounding them causing a microseconds blue flash... a subcritical assembly is simply not releasing that many particles, so the flashes are only visible to very sensitive detectors, but once the assembly goes hot there are enough reactions that it is visible to the naked eye. Somewhere like a spent fuel pool, where the items are hot due to residual reactiveness, the blue glow is the warning that you would seriously not enjoy being there, but it is not a safe warning measure because the light comes well after dangerous levels of radioactivity. Consider the Lia Incident for details of where that blue glow was not present, and it was still VERY lethal, or any of the half dozen cobalt 30 accidents.
@@leechowning8728 Cherenkov radiation has nothing to do with fission products. It's caused by charged particles moving through a medium faster than light (air and water are not vacuum).
It's an excitation and the blue glow is bleeding off the excitation.
2:40 - Poker-faced giggles
Something I think they didn't really understand at that point was that even low levels of radiation can be harmful if you're around it long enough. The demon core wasn't an on/off thing, it was always emitting SOME radiation. It's like being around a bonfire vs being in a burning building. The smoke is bad for you regardless, but the more of it there is, the faster it's going to kill ya.
With the Demon Core, why not have permanently installed plastic bumpers to prevent accidental contact?
"Well, that does it"....
He knew what had just happened, and that it was over for him 😔
Of course, this wouldn't be allowed today and of course today we look at this and see "bad idea" written all over it, but that is because these incidents have already happened and we have learned from those mistakes. Before they were made however, while a disaster could have been predicted, we simply didn't know what would happen and the only real way to find out was to test it, and then find out the hard way.
Question... what would have happened if he wasn't able to get the top off of the sphere? What if everyone just ran?
I remember a long time ago reading a sci-fi fantasy book where a guy made a crude nuke in a granite mountain by boring a hole into the side of it. Cant remember if he had a metal cylinder or not to line the hole. Somehow had plutonium disc, enriched uranium disc or something then a small explosive charge in that order. Sealed it up and deleted part of the mountain for some reason. Cannot remember the name of that book, but as a kid I was like that seems way too easy. It was my first exposure to nuclear and nuclear weaponry. I was pretty young and thought it was really cool, albeit crude that you could do that and make it work. Of course that was before I learned how hard it is to get plutonium and weapons grade uranium. Ill have to search for that book to get the title, or if someone knows the book I am talking about. I'm really bad at remembering author names and titles lol plus this was back in the 90s and I was like 10 years old or younger. And that is the only thing I remember from the book lol. 😋 But it did get me more engaged into science.
As always love your content!
sounds remotely similar to the nightlord series, which the titular character Halar/Eric creates a nuclear .....power source not a reactor but... its hard to explain.
the gun-type weapon used on Hiroshima is similar to what you describe, simply one piece of enriched uranium shot at another by an explosive charge to form a combined critical mass. the efficiency is much lower than more advanced implosion devices, but it's by far the simplest and most reliable way to design a weapon.
Would the experiments even be valid given the time constant of the delayed neutrons?
They could have assembled a supercritical geometry but not have a valid instrument response because they adjust the geometry faster than the system could respond.
Or were they manipulating a core that was already in the delayed critical regime, looking for the prompt critical dragon?
Are there currently any 'Approach to Criticality ' experiments being done?
Jon
I believe there are current 'approach to criticality' experiments, hopefully with much more stringent controls and safety procedures: organizations.lanl.gov/ncerc/
Great commentary, mister engineer.
Amazing how we can't blame this on ignorance, for as soon as they achieved criticality, they immediately knew what they've done.
13:23 "Hey, who left this screwdriver here?"
What I get from the history of science is that scientists are all madman...
"Not allowed" and "under no circumstances" keep being brought up...
I wonder... What if we established a "Cowboy Science Lab" somewhere _even more remote_ than Los Alamos? Somewhere in East Jesus, Alaska; somewhere where the only rule is "never stop documenting what you do, ever," and safety is "your business and nobody else's." ...
10:50 causality says NOTHING outside of 0.002998mm can react fast enough
Hey, I'm a new view and I was hoping you could do a reaction video and talk about Sam O'nellas Thorium Video
I second this, Sam O'Nella is so good lol
Not only killing those in the room, what would have happened to the entire Manhattan project if either of these people had not been able to interrupt the prompt critical reaction? Could the entire crew of scientists and engineers have been wiped out in one shot?