When Scott was showing the flowchart for the process for making Plutonium in a reactor, it reminded me of your channel, Cody... and here you are! What a coincidence!
My favourite factoid about the Trinity test is that after the war they released photos of the test...which included a time stamp and distance scale. A physicist named G.I. Taylor (who had worked on the manhatten project) used those images, with a spot of dimensional analysis, and published papers wherein he calculated (to a remarkable degree of accuracy) what the explosive yield of the device was. He got in a little bit of trouble for this, as the number he'd worked out was very classified...but when it was discovered that he was able to work this out from information that was in the public domain, he was let off, and an important lesson was learnt about never underestimating what a clever person will do with information.
A scientist (It may have been Fermi) calculated the Trinity yield by throwing bits off paper into the air, and measuring how far they traveled as the shock wave passed. I think this method predicted a yield of 20 kilotons.
In later years, we used a surprisingly simple method to get a first-order approximation of a weapon's actual yield during a test. Remember those smoke trails you always see next to the mushroom cloud? Those were left by rockets, and were at known points perpendicular to the camera's line of sight. By watching high-speed footage of the test frame-by-frame, the visible disruption of those smoke trails from atmospheric lensing would allow them to track the passage of the shock front... and by calculating the speed at which it was going (from distance between trails and number of frames it took to go that distance), they could get a fairly close estimate of how big a boom they actually got.
This lesson was promptly forgotten by President Trump when he tweeted out classified images of an Iranian launch failure taken by a KH-11 satellite. Scott’s video on the subject uses the publicly known information of the KH-11’s imaging sensor to determine the exact orbit of the spacecraft, allowing the tracking number of that specific satellite to be determined.
Really? I don't understand any of them. And I lived with a scientist who did his doctoral thesis on the third way they make these. They use photon energy; he did his thesis on photons. That's all I know. I couldn't even read the first page of his paper, which was over 200 pages long. I didn't understand the first page. Math & Science were my weakest subjects. Language was supposed to be my strength but you'd never guess it now. I've been trying to learn German for 5 months. Not going well at all.
X-ray photons are used to detonate secondary fusion stage in thermonuclear (hydrogen) bombs! Your roommate could have been the hydrogen bomb scientist, really... Of course no lamp can do it, those photons are produced by regular (or boosted) fission nuclear bomb=)
An underappreciated British contribution to the Manhattan Project, quite apart from the Frisch/Peierls Memorandum that kicked the whole thing off. The American experimenters were getting nowhere with implosion until a) Jeff Taylor showed them the way they were going wouldn't work and b) James Tuck told them about his work with shaped charges.
Nah; this is all "open source" stuff at this point. The only limiting factor in making nuclear weapons is not information; it's acquiring or creating the materials. The "information" cat got out of the bag 60-odd years ago, and there's no putting it back. What he's discussing is stuff that kids learn in college these days, at least those who take nuclear physics courses.
I'll fill in what Scott left out after the 8 min mark. Detonation wave profiles take the form of a leading edge pressure spike followed by a region of rarefaction. The shock reflection that would occur at the Al/U interface would produce a higher pressure behind the shock front, minimising the rarefaction that occurred behind the shock front, thus maintaining pressure for a good distance behind it, and thus allowing for the entirety of the core to be compressed to a higher degree, rather than the material that was just behind the shock front at that period of time.
yeah ... think of it what you want but some technology had to be invented from scratch to make the manhattan project a reality and others were advanced by decades.
In the video at the end, you can see a few of these engineers (actually nuclear scientists): Feynman on the left (no shirt, slight belly), Oppenheimer (slim man with the hat) who was the director of the program. The others I didn't recognize. I wonder who the guy with a pen on his ear is.
Taleric1 "Oh, I'll just hold these two halves of a reflector over a plutonium core juuuuust barely apart with a screwdriver.... *screwdriver slips and both halves cover the core* Oh damn... *radiation intensifies* Hm, well, fuck."
There wasn't a standard operating procedure at the time, but safety was an issue (since there were two instances where people screwing around with the Demon Core lead to fatalities.
I've watched/read a lot of stuff about the Manhattan project and nuclear bombs/energy, and so far there have been new info for me in each of your videos. I love how you explain the details instead of just glancing over them.
Have you read the Nuclearsecrecy blog, by the creator of Nukemap? That goes into a lot more detail than anything else I have read. Stuff like how a lot of the energy of an H bomb actually comes from fission.
Reactors make plutonium as a by product the a goal for plutonium is more cheaper easier bombs that is the point of of going ror plutonium. Enriched uranium even at low none weapons grade is a problem because with that you can make reactors and the reactors will make your easy bomb material plutonium the ignition timing for the explosives is tricky but only down to nanosecond tolerances easily within the capability of switching diode available for purchase through digikey not that big a deal to set up if you have a 100 mhz scope and can read the graticule.
I worked on submarine nuclear reactors when I was in the US navy and these videos cover most of the material taught pretty well, I’d love to see many more videos like this, I would definitely watch a series about shock dynamics
Thanks, chilling stuff. I grew up in the cold war and we were warned about 6 minutes before explosion. Hope those days are gone forever. Thanks for your very professional presentation.
Excellent Video! I appreciate you taking the time to educate us on this matter. This also puts into perspective how intelligent the people involved in the Manhattan project were.
Great videos. You're doing an impressive job explaining a lot of these complex technical concepts and making them understandable for most folks. Looking forward to the rest of the series. If you're feeling really confident at explaining difficult to comprehend subjects, how about one on how anyone can think MAD is such a great idea, which is inexplicable to me and a lot of others who think it's simply insane.
After 4 years, a question I've had about why gun type isn't more widespread today is finally answered, and with 2 good reasons instead of 1 half-arsed answer. Thank you very much Scott!
The implosion reminds me of neutron star formation. A huge collapse crushing the center down with huge pressure. Of course, implosion only crushes the pit down to about half it size vs neutron stars whose collapse crushes the stars core down ~idk ...10,000 times as the electron degeneracy pressure is overcome and atoms collapse into just the nucleus ...or neutrons. Love your video's Scott !
We as a species didn't know about radioactivity until the late 1800's. not even half a century later we figured all this out. Will always boggle my mind. Smart people? Alien tech? Amazing stuff that 99.9% of the population doesn't think about.. Amazing explanation/simplification Mr. Manely!
I love the way you expect everyone is following along! In this episode I was fascinated to learn about the U238 tamper. It's amazing to think that U238 actually accounted for as much as 20% of the total yield of the Fat Man
It´s hard to wait till you get to Castle Bravo and fusion. I love this series. Do you already know where you will stop are do you go up to the point where you´ll talk about Tokamaks Stellators and the National Ignition Facility?
I know that I need at least 3 more parts covering 1) Improving implosion devices (hollow cores, fission boosting, etc) 2) Thermonuclear 3) Enriching Uranium & Manufacturing Plutonium.
Sounds cool. maybe if yoou have time and Ask nice the people at the NIF may give you a tour for the Video. but these three Parts are already a good thing to look foward to. But it´s always a problem of time and Space and all that inside a curvey Spacetime. Sometimes I wish we would have Tardisses or what ever the plural of TARDIS is.
and after that there is gen 4 nuclear weapons too : antimatter initiated fusion weapons; which can theoretically be minimized to a *much* smaller scale .
And while we're at it, you can go off a tangent and use 'Plutonium production' as a subject to cover nuclear power reactors, the various types of that, notable incidents, and planned future nuclear power generation?
Excellent video with great detail all the way through. I have to say, this is my favorite nerd-fest channel for science related topics. I have been subbed for years now as I remember when your vid popped up on your trek to Oregon for the 2017 eclipse. Funny thing is I invited my wife and friends to accompany me on that "Once in a lifetime chance" to simply drive to where the total eclipse will happen, but no one understood how cool this was going to be. In my case I drove from Victoria, BC, to Madras Oregon and I ended up with my younger brother joining me for that trip as he knew what this really was. I tried to explain to my friends that people travel all around the world to witness this. I was talking about going camping over a long weekend.
If I try to estimate the number of spontaneous fissions, I use this logic: - remaining quantity Q(t) = Q(0) exp(kt) where k = ln(0.5)/t_half - decays per second = -Q(0) k exp (kt) = ln(2)Q(t)/t_half - spontaneous fissions per second = Q(t) * P * ln(2)/t_half Using the table at 2:53, converting the half live periods to seconds, and setting Q(t) to Avogadro's number, I get these figures for the *Number of fissions per mole per second* : For Pu-240: 6.0E23 * 5.0E-6 * ln(2)/5.0E18 = 0.42 For Pu-239: 6.0E23 * 4.4E-10 * ln(2)/1.7E23 = 1.1E-9 Even with a pit of 6 kg (25 moles) consisting of 80% Pu239 and 20% Pu-240 I cannot see how more than about 2 spontaneous fission per second would occur, so from this b-o-t-e-calculation I would say that 1 millisecond would be quick enough in 99.8% of the cases, and from these data I don't see how timescales of microseconds are so crucial to prevent predetonation. Anyone?
Hi Scott, Longtime KSP watcher here. I want to say you'r HSB t-shirt is great. When I lived in SF I loved that festival. Keep up the great work and hope to see you in GGP some day!
The entire 20th century is truly a technological golden age. The rate at which we progressed from crude planes that flew a few hundred yards to ubiquitous home computers and thousands of artificial satellites is staggering. Player pianos to 3D accelerated video games.
The two horrific world wars and the tense stand-off between two nations that could have ended life as we knew it likely helped accelerate that, somewhat.
Shaped Charges are the Coolest Thing I ever Learned About! Especially with the Copper Plate Penetrator. The Explosive Shock Wave propagates from Point of Ignition and when it reaches the Lens, it Focuses into a Point Source. This was used in the Oklahoma City Attack.
Hi Scott, Thank you for being such a Great Teacher! I only studied naval reactors. Your explanations are easy to follow and my knowledge base was able to follow you. 👍
Great piece. Scott, did you know that the massive pressure, during an atmospheric detonation, centered on the pit is sufficient to create opaque air for a very short period until the explosion expands and releases light. Hence the double flash that satellite sensors look for.
Early on in the project, Fermi's joke/slight speculation about the bomb possibly igniting the atmosphere was a serious concern. They did a lot of calculations on that and concluded it was PROBABLY not possible. Nobody was 100% certain going in to the Trinity test, just mostly pretty sure, maybe 99% it wasn't going to be a thing.
This april 1 I went to Trinity site as well as the large radio telescope array in New Mexico. Worth the visit. Only can go to trinity site twice a year so plan accordingly.
First time I've seen photo of implosion test result on metal cylinder. Fascinating! After decades of gobbling up data on nuclear weapons, I must say you have demonstrated very fine knowledge of the process in an excellent video. I learned some new things here, like the complexity of the "urchin" neutron initiator. Now, how did they print such a modern looking, stick on label on that first 2.5 micro gram of PU239 sample? Do you have any photos of the inside of the gaseous diffusion plant at Oak Ridge, during its operation? I'm always stunned by what that plant accomplished, and how fast it was built. Thank you.
I'm am active subscriber of yours, Scott, but I didn't even know this was your video until the "Hullo!" Always a pleasant surprise. I guess it stands to reason that if somebody is into rockets they will be into nuclear weaponry as well. Gotta love those Rayleigh-Taylor instabilities.
1:40 ...chance that the chain reaction would start before the core was fully inserted, resulting in a premature detonation with a much lower yield. I have this problem sometimes.
Really appreciate your intelligent, concise, and engaging videos. Well done Mr Manley! For those who appreciate a good read and are interested in learning more about the history of nuclear weapons: The Manhattan Project by Richard Rhodes Dark Sun, again by Richard Rhodes Stalin And The Bomb by David Holloway US Nuclear Weapons: A secret History by Chuck Hansen (long out of print
FYI. Fermi was not joking. His numbers showed there was a scenario that said the bomb could ignite the atmosphere. I have heard this before and I can tell you that why he believes the probability was low, some calculations indicated this could have occurred. Love your series and thanks for not getting overly detailed especially with the timing plugs and other things I won’t get into here. Very good job!
Scott Manley Well, my grandfather worked with Fermi. He claimed he wasn’t joking, at least initially. He was very concerned. However, all that is neither here nor there. The fact is you are doing an excellent job on these videos! Appreciate you keeping these great men’s memory alive.
8:18 Engineering shockwave interference patterns using pencil, paper, and slide-rules (not super-computers or even calculators) deserves it's own video. Damn, those were some geniuses. How did they even measure explosive speeds nearly 5 miles per second to the necessary accuracies needed without computers? As destructive (and controversial) as Hiroshima and Nagasaki were, no one can deny the shear brilliance of the human mind.
Excellent video on going nuclear, would love to see more. Everything you wanted to know in four parts. Learned a tremendous lot I did not know awesome thanks great series
The Earth I'm no nuclear physicist, but my understanding is that the heat and pressure created by the fission causes the hydrogen nuclei in the plasma to near the speed of light, allowing colisions that produce fusion and a crap-ton of energy.
it's worth noting 'fusion bombs' (technically thermonuclear bombs) produce so much energy by combining the forces of fusion and fission. A great deal of their energy is still fission based.
Always amazes me how they were able to build something like this with the equipment they had. On another note I love your outro music (google Tigoolio - Fatality, it's on ccmixter for anyone who's interested)
Could you do a video on the detonation synchronization circuit. It must have been such a challenge to get all of those explosives to sync up at the same time with the technology available at that time.
Very interesting. I had already read quite a bit about the Manhattan project and yet I somehow managed to learn new stuff in this video. Could you please list your sources though? Apart from the Critical Assembly Simulator by Alex Wellerstein I've no idea where all the pictures and simuations come from.
Watching Oppenheimer the other day I thought it was funny how they placed the last section of explosive lens like it was made of styrofoam. They just picked it up and gently fitted it into the opening and let it down slowly with the tips of their fingers.
if by brute force ,exploding lenses were used to trigger fission, other type of energy could achieve the same thing ? What about gamma ray lenses ? Would that do something ... ?
Wow much details in this. I'm first time hear about construction of the neutron generator in this video i was thinking that is classified information :D Great job Scott, fly safe or better fission safe :)
Around 4:00 you explain that the shorter distances in an implosion device mean that the time between onset and maximum criticality is very short. But how is this achieved? With a shorter 'barrel' I expect lower implosion speed of the pit when being compressed. The compression phase lasts about 5μs?
Fermi also suspected that the electromagnetic pulse from the Trinity explosion would destroy measuring instruments, so they were shielded. Despite the effort a significant number were destroyed. Someone must have been taking notes because it led to experiments like Starfish Prime, and the Soviet K bomb (EMP) test.
Story about one of my old climbing partners When [my partner] arrived at Los Alamos, his supervisor handed him a pea-size chunk of dull grayish metal and said, This is the world's supply of plutonium. I m going to lunch; please brief me on its metallurgical properties when I get back. [He] pondered his task, then put the pellet on an anvil and smacked it with a hammer, and later reported to his supervisor that it was malleable. As he recounted later, fortunately it was very impure plutonium; otherwise it would have pulverized and contaminated the entire building. That's just one of his after dinner tales about being on the cutting edge.
Again, I've read what I thought was a lot of the publicly available literature around these devices, but I'm clearly missing huge chunks, as I'd never even heard of the efforts for Thin Man. What are your major references?
yessssss!! really enjoy thees videos!
Cody'sLab No, just no! Don't built atom bombs on your background please 😂
Hi I'm Cody and welcome to my Manhattan project!
Do you have some plutonium on your collection?
When Scott was showing the flowchart for the process for making Plutonium in a reactor, it reminded me of your channel, Cody... and here you are! What a coincidence!
cue articles about the "Nuclear Boyscout"
My favourite factoid about the Trinity test is that after the war they released photos of the test...which included a time stamp and distance scale. A physicist named G.I. Taylor (who had worked on the manhatten project) used those images, with a spot of dimensional analysis, and published papers wherein he calculated (to a remarkable degree of accuracy) what the explosive yield of the device was.
He got in a little bit of trouble for this, as the number he'd worked out was very classified...but when it was discovered that he was able to work this out from information that was in the public domain, he was let off, and an important lesson was learnt about never underestimating what a clever person will do with information.
A scientist (It may have been Fermi) calculated the Trinity yield by throwing bits off paper into the air, and measuring how far they traveled as the shock wave passed. I think this method predicted a yield of 20 kilotons.
And said G.I., Ted Taylor, went on to be one of our preeminent nuclear weapons designers postwar.
In later years, we used a surprisingly simple method to get a first-order approximation of a weapon's actual yield during a test. Remember those smoke trails you always see next to the mushroom cloud? Those were left by rockets, and were at known points perpendicular to the camera's line of sight. By watching high-speed footage of the test frame-by-frame, the visible disruption of those smoke trails from atmospheric lensing would allow them to track the passage of the shock front... and by calculating the speed at which it was going (from distance between trails and number of frames it took to go that distance), they could get a fairly close estimate of how big a boom they actually got.
@@rdfox76 at last... I always wonder whats that trail surrounding during early parts of explosion mushroom... Thanks for the info!
This lesson was promptly forgotten by President Trump when he tweeted out classified images of an Iranian launch failure taken by a KH-11 satellite. Scott’s video on the subject uses the publicly known information of the KH-11’s imaging sensor to determine the exact orbit of the spacecraft, allowing the tracking number of that specific satellite to be determined.
Explosive lenses are such a cool idea! Great video :)
thedreadnote
Next they are going to come up with the explosive telescope.
Really? I don't understand any of them. And I lived with a scientist who did his doctoral thesis on the third way they make these. They use photon energy; he did his thesis on photons. That's all I know. I couldn't even read the first page of his paper, which was over 200 pages long. I didn't understand the first page. Math & Science were my weakest subjects. Language was supposed to be my strength but you'd never guess it now. I've been trying to learn German for 5 months. Not going well at all.
X-ray photons are used to detonate secondary fusion stage in thermonuclear (hydrogen) bombs! Your roommate could have been the hydrogen bomb scientist, really... Of course no lamp can do it, those photons are produced by regular (or boosted) fission nuclear bomb=)
An underappreciated British contribution to the Manhattan Project, quite apart from the Frisch/Peierls Memorandum that kicked the whole thing off. The American experimenters were getting nowhere with implosion until a) Jeff Taylor showed them the way they were going wouldn't work and b) James Tuck told them about his work with shaped charges.
That part totally blew my mind, such a simple yet smart solution.
Is part 5 going to be about how to remove yourself from government-watchlists ?
you mean Google's 'analytic' system :-)
Nah; this is all "open source" stuff at this point. The only limiting factor in making nuclear weapons is not information; it's acquiring or creating the materials. The "information" cat got out of the bag 60-odd years ago, and there's no putting it back. What he's discussing is stuff that kids learn in college these days, at least those who take nuclear physics courses.
Nah, it's stuff kids learn in middle school during GCSE's between 14 and 16 years old, and it's mandatory. Really simple stuff :P
proof of open-source-ness: en.wikipedia.org/wiki/Nuclear_weapon_design
@jesper O lmao
I'll fill in what Scott left out after the 8 min mark.
Detonation wave profiles take the form of a leading edge pressure spike followed by a region of rarefaction. The shock reflection that would occur at the Al/U interface would produce a higher pressure behind the shock front, minimising the rarefaction that occurred behind the shock front, thus maintaining pressure for a good distance behind it, and thus allowing for the entirety of the core to be compressed to a higher degree, rather than the material that was just behind the shock front at that period of time.
Sitting at the fireplace, having a coffee, feeding my brain watching your video, a saturday morning can't start better.
☕️
When you do nuclear science CHECK YO STAGIN!
Ave Vovus! You’re lucky that joke didn’t bomb...
And make sure you buy the t-shirt!
A missile with a nuclear warhead doesn't need any parachutes, so there's no problem xD
Yes, I know that this wasn't your point.
@togamid if you stage the detonation, before the launch ... BIG PROBLEM XD
togamid Some air drop bombs have chutes.
Premature detonation while the core is not even fully inserted. I hate when that happens...
I see what you did there...
@@dzejrid oh man... you win the internet
That’s why you need a fast insertion time
Just think about boron on a cold day.
Shorter gun barrels increases chances of premature detonation? damn...
The engineers involved absolutely earned their slide-rules.
yeah ... think of it what you want but some technology had to be invented from scratch to make the manhattan project a reality and others were advanced by decades.
In the video at the end, you can see a few of these engineers (actually nuclear scientists): Feynman on the left (no shirt, slight belly), Oppenheimer (slim man with the hat) who was the director of the program. The others I didn't recognize. I wonder who the guy with a pen on his ear is.
@@InXLsisDeo Looks like that might be Louis Slotin on the left, leaning into the bomb. Maybe Harry Daghlian Jr on the right?
You have to cover the accidents that occurred with the demon core.
Taleric1 "Oh, I'll just hold these two halves of a reflector over a plutonium core juuuuust barely apart with a screwdriver.... *screwdriver slips and both halves cover the core* Oh damn... *radiation intensifies* Hm, well, fuck."
"Everyone mark where you are standing, so we can calibrate your radiation dose vs. how much of your DNA falls apart."
Long Dong Silver I wonder about the safety of standard operational procedure at that time 😓
There wasn't a standard operating procedure at the time, but safety was an issue (since there were two instances where people screwing around with the Demon Core lead to fatalities.
Penningtontj It was definitely a new field of study without a doubt. What a shitty way to go...
I've watched/read a lot of stuff about the Manhattan project and nuclear bombs/energy, and so far there have been new info for me in each of your videos. I love how you explain the details instead of just glancing over them.
Have you read the Nuclearsecrecy blog, by the creator of Nukemap? That goes into a lot more detail than anything else I have read. Stuff like how a lot of the energy of an H bomb actually comes from fission.
@@charleslambert3368 That's very basic information available on wikipedia..
Reactors make plutonium as a by product the a goal for plutonium is more cheaper easier bombs that is the point of of going ror plutonium. Enriched uranium even at low none weapons grade is a problem because with that you can make reactors and the reactors will make your easy bomb material plutonium the ignition timing for the explosives is tricky but only down to nanosecond tolerances easily within the capability of switching diode available for purchase through digikey not that big a deal to set up if you have a 100 mhz scope and can read the graticule.
The smart guys were the ones that made the kriton ignitors
What have you read or watched? We're you sober? We're there a lot of plush ponies? You won't find physics in a happy meal 🤣
I worked on submarine nuclear reactors when I was in the US navy and these videos cover most of the material taught pretty well, I’d love to see many more videos like this, I would definitely watch a series about shock dynamics
That's not a glowing recommendation 😁🤣
Thanks, chilling stuff. I grew up in the cold war and we were warned about 6 minutes before explosion. Hope those days are gone forever.
Thanks for your very professional presentation.
“Shock dynamics are incredibly complex and worth videos of their own.”
Please?
That's his way of saying "Sorry, but need-to-know basis."
The information is available online. Ask any questions you have.
@@Evan_Bell Can u provide me the links. Tnks Evan
@@fightingforcatalonia To what? Just Google it.
I still say Scott can be a bond villian
Fly safe Mr bond.... hahahaha
pyro lopez Ahahahahahaaa hahaha!
I could easily see Scott as Ernst Blofeld
Scott, I'm really enjoying these Going Nuclear videos so far but could you please skip ahead to the DIY episodes?
Sincerely,
Kim
kek
also, 42nd like.
101010
I'm on to you Kim Possible
@@noahhastings6145 No secrets here.
Excellent Video! I appreciate you taking the time to educate us on this matter. This also puts into perspective how intelligent the people involved in the Manhattan project were.
Plutonium - not only highly radioactive but phenomenally toxic as well. Lovely stuff.
Try Polonium. Just 1 gram would kill 10 million people.
Great videos. You're doing an impressive job explaining a lot of these complex technical concepts and making them understandable for most folks. Looking forward to the rest of the series. If you're feeling really confident at explaining difficult to comprehend subjects, how about one on how anyone can think MAD is such a great idea, which is inexplicable to me and a lot of others who think it's simply insane.
After 4 years, a question I've had about why gun type isn't more widespread today is finally answered, and with 2 good reasons instead of 1 half-arsed answer. Thank you very much Scott!
+Stretchwings that’s exactly what I was hoping to do with this series.
I've been reading Manhattan project books on and off for years and each time I learn something new.
This series is great!
The implosion reminds me of neutron star formation. A huge collapse crushing the center down with huge pressure. Of course, implosion only crushes the pit down to about half it size vs neutron stars whose collapse crushes the stars core down ~idk ...10,000 times as the electron degeneracy pressure
is overcome and atoms collapse into just the nucleus ...or neutrons. Love your video's Scott !
We as a species didn't know about radioactivity until the late 1800's. not even half a century later we figured all this out. Will always boggle my mind. Smart people? Alien tech? Amazing stuff that 99.9% of the population doesn't think about..
Amazing explanation/simplification Mr. Manely!
I love the way you expect everyone is following along! In this episode I was fascinated to learn about the U238 tamper. It's amazing to think that U238 actually accounted for as much as 20% of the total yield of the Fat Man
The actual value was 30.8%.
Learning lots of details General Groves would spin about. Really helping my hobby project. Thanks!
It´s hard to wait till you get to Castle Bravo and fusion. I love this series.
Do you already know where you will stop are do you go up to the point where you´ll talk about Tokamaks Stellators and the National Ignition Facility?
I know that I need at least 3 more parts covering
1) Improving implosion devices (hollow cores, fission boosting, etc)
2) Thermonuclear
3) Enriching Uranium & Manufacturing Plutonium.
Sounds cool. maybe if yoou have time and Ask nice the people at the NIF may give you a tour for the Video. but these three Parts are already a good thing to look foward to. But it´s always a problem of time and Space and all that inside a curvey Spacetime. Sometimes I wish we would have Tardisses or what ever the plural of TARDIS is.
Yesss, enrichment and production. Looking forward to that. The scale of those operations is absolutely mind boggling.
and after that there is gen 4 nuclear weapons too : antimatter initiated fusion weapons; which can theoretically be minimized to a *much* smaller scale .
And while we're at it, you can go off a tangent and use 'Plutonium production' as a subject to cover nuclear power reactors, the various types of that, notable incidents, and planned future nuclear power generation?
Scott's outro music always gets my attention; in any mood, I await the almost spiritual awe I feel at the boogle-blong just before it cuts off.
Thanks Scott! You're a great lecturer!
Thank you for the detailed explanation. I've never heard a better one.
These just get better and better, Scott! Thank you!
Science and history together are awesome.
Excellent video with great detail all the way through. I have to say, this is my favorite nerd-fest channel for science related topics. I have been subbed for years now as I remember when your vid popped up on your trek to Oregon for the 2017 eclipse. Funny thing is I invited my wife and friends to accompany me on that "Once in a lifetime chance" to simply drive to where the total eclipse will happen, but no one understood how cool this was going to be. In my case I drove from Victoria, BC, to Madras Oregon and I ended up with my younger brother joining me for that trip as he knew what this really was. I tried to explain to my friends that people travel all around the world to witness this. I was talking about going camping over a long weekend.
One day in the future we will be able to mine plutonium directly from pluto so we don't have to make it in a lab.
I’ve been in the reactor build at Oak Ridge. The reactor and all the equipment needed to operate are still there.
The more details I learn about nuclear weapons development, the more impressed I am about the speed at which they were able to create them.
If I try to estimate the number of spontaneous fissions, I use this logic:
- remaining quantity Q(t) = Q(0) exp(kt) where k = ln(0.5)/t_half
- decays per second = -Q(0) k exp (kt) = ln(2)Q(t)/t_half
- spontaneous fissions per second = Q(t) * P * ln(2)/t_half
Using the table at 2:53, converting the half live periods to seconds, and setting Q(t) to Avogadro's number, I get these figures for the *Number of fissions per mole per second* :
For Pu-240: 6.0E23 * 5.0E-6 * ln(2)/5.0E18 = 0.42
For Pu-239: 6.0E23 * 4.4E-10 * ln(2)/1.7E23 = 1.1E-9
Even with a pit of 6 kg (25 moles) consisting of 80% Pu239 and 20% Pu-240 I cannot see how more than about 2 spontaneous fission per second would occur, so from this b-o-t-e-calculation I would say that 1 millisecond would be quick enough in 99.8% of the cases, and from these data I don't see how timescales of microseconds are so crucial to prevent predetonation.
Anyone?
Is it Scott's head on the preview?
of course it is
KKKKKKKKKKKKKKKKKKKKKKKKKKK
^v^
Hi Scott, Longtime KSP watcher here. I want to say you'r HSB t-shirt is great. When I lived in SF I loved that festival. Keep up the great work and hope to see you in GGP some day!
The entire 20th century is truly a technological golden age. The rate at which we progressed from crude planes that flew a few hundred yards to ubiquitous home computers and thousands of artificial satellites is staggering. Player pianos to 3D accelerated video games.
+Sam Harkins but let’s be clear, Player Pianos are amazing, and in fact better than many video games.
and yet the amount of people the think Earth is flat grows...
The two horrific world wars and the tense stand-off between two nations that could have ended life as we knew it likely helped accelerate that, somewhat.
Favorite series on youtube right now!
Shaped Charges are the Coolest Thing I ever Learned About! Especially with the Copper Plate Penetrator. The Explosive Shock Wave propagates from Point of Ignition and when it reaches the Lens, it Focuses into a Point Source.
This was used in the Oklahoma City Attack.
Hey dude, thank you for being my favorite UA-cam channel and always putting out quality content.
Hi Scott, Thank you for being such a Great Teacher!
I only studied naval reactors. Your explanations are easy to follow and my knowledge base was able to follow you. 👍
Great piece. Scott, did you know that the massive pressure, during an atmospheric detonation, centered on the pit is sufficient to create opaque air for a very short period until the explosion expands and releases light. Hence the double flash that satellite sensors look for.
Early on in the project, Fermi's joke/slight speculation about the bomb possibly igniting the atmosphere was a serious concern. They did a lot of calculations on that and concluded it was PROBABLY not possible. Nobody was 100% certain going in to the Trinity test, just mostly pretty sure, maybe 99% it wasn't going to be a thing.
Fantastic video, crazy background info I did not know before!
This is a fascinating series Scott! Thanks so much for making these. Can't wait for next one!
Scott you should come up to eastern Washington and visit the Hanford site. You can go on a tour of B Reactor and visit LIGO.
Well presented! Looking forward to the next one in the series.
This april 1 I went to Trinity site as well as the large radio telescope array in New Mexico. Worth the visit. Only can go to trinity site twice a year so plan accordingly.
Time drags between these videos. Keep 'em coming!
Scientists: Wait! There is a possibility to ignite the whole Earth atmosphere!
Same Scientists: COOL! Let’s place bets!
First time I've seen photo of implosion test result on metal cylinder. Fascinating! After decades of gobbling up data on nuclear weapons, I must say you have demonstrated very fine knowledge of the process in an excellent video. I learned some new things here, like the complexity of the "urchin" neutron initiator. Now, how did they print such a modern looking, stick on label on that first 2.5 micro gram of PU239 sample?
Do you have any photos of the inside of the gaseous diffusion plant at Oak Ridge, during its operation? I'm always stunned by what that plant accomplished, and how fast it was built. Thank you.
I'm am active subscriber of yours, Scott, but I didn't even know this was your video until the "Hullo!" Always a pleasant surprise. I guess it stands to reason that if somebody is into rockets they will be into nuclear weaponry as well. Gotta love those Rayleigh-Taylor instabilities.
Excellent show.
1:40 ...chance that the chain reaction would start before the core was fully inserted, resulting in a premature detonation with a much lower yield.
I have this problem sometimes.
Congrats on reaching the magic million Scott. Love your work! 😊👍
This series is right up there with your What Is Rocket Fuel? video. Love them :]
Looking forward to the next vid, presume you'll be going onto two-stage Teller-Ulam designs.
+Electricfox gotta talk about some other improvements first
Ah, boosted fission?
Really appreciate your intelligent, concise, and engaging videos. Well done Mr Manley!
For those who appreciate a good read and are interested in learning more about the history of nuclear weapons:
The Manhattan Project by Richard Rhodes
Dark Sun, again by Richard Rhodes
Stalin And The Bomb by David Holloway
US Nuclear Weapons: A secret History by Chuck Hansen (long out of print
FYI. Fermi was not joking. His numbers showed there was a scenario that said the bomb could ignite the atmosphere. I have heard this before and I can tell you that why he believes the probability was low, some calculations indicated this could have occurred.
Love your series and thanks for not getting overly detailed especially with the timing plugs and other things I won’t get into here. Very good job!
+Prof2You Smithe he was joking because the math had been done prior to the test and there was no chance, he knew that when he shared the story.
Scott Manley Well, my grandfather worked with Fermi. He claimed he wasn’t joking, at least initially. He was very concerned. However, all that is neither here nor there. The fact is you are doing an excellent job on these videos! Appreciate you keeping these great men’s memory alive.
8:18 Engineering shockwave interference patterns using pencil, paper, and slide-rules (not super-computers or even calculators) deserves it's own video. Damn, those were some geniuses. How did they even measure explosive speeds nearly 5 miles per second to the necessary accuracies needed without computers?
As destructive (and controversial) as Hiroshima and Nagasaki were, no one can deny the shear brilliance of the human mind.
Scott: Thanks for these videos, I really enjoy your content - keep up the good work.
Mr. Manley, I gotta say I love the series.
Amazing stuff. The creepy, subtle music is perfect for this topic.
Such in depth great videos Scott! Thank you!
You should rename this video "The gadget or the soccer ball of DOOM!"
Hey Scott this series is awesome! Thanks for making it.
Love these science/history lessons. Keep 'em coming!
Excellent video on going nuclear, would love to see more. Everything you wanted to know in four parts. Learned a tremendous lot I did not know awesome thanks great series
Really enjoying this series.
Yay for nuclear sciences!
You're on a list Scott, you're on a list.
This is really fantastic content, thanks Scott !
The gadget is compressing plutonium with the power of tnt
So is fusion bombs using the power of fission to compress hydrogen isotopes?
The Earth I'm no nuclear physicist, but my understanding is that the heat and pressure created by the fission causes the hydrogen nuclei in the plasma to near the speed of light, allowing colisions that produce fusion and a crap-ton of energy.
The pressure of radiation do the most of the job.
Also.. dont discount which lithium isotopes are in your bomb or youll end up with something a WHOLE lot larger than you anticipated ;)
Did someone tell the Americans about Lithium 7 >_
it's worth noting 'fusion bombs' (technically thermonuclear bombs) produce so much energy by combining the forces of fusion and fission. A great deal of their energy is still fission based.
Always amazes me how they were able to build something like this with the equipment they had. On another note I love your outro music (google Tigoolio - Fatality, it's on ccmixter for anyone who's interested)
Could you do a video on the detonation synchronization circuit. It must have been such a challenge to get all of those explosives to sync up at the same time with the technology available at that time.
Very interesting. I had already read quite a bit about the Manhattan project and yet I somehow managed to learn new stuff in this video.
Could you please list your sources though? Apart from the Critical Assembly Simulator by Alex Wellerstein I've no idea where all the pictures and simuations come from.
Watching Oppenheimer the other day I thought it was funny how they placed the last section of explosive lens like it was made of styrofoam. They just picked it up and gently fitted it into the opening and let it down slowly with the tips of their fingers.
6:19 Where did you get that picture from? I've always been curious as to how they were able to test the explosive lenses.
Trinity and Beyond the Atomic bomb movie, is one of my favorite documentaries.
More and faster! Please and thank you.
Great series Scott Manley. It's a terrible reality but intensely fascinating.
if by brute force ,exploding lenses were used to trigger fission, other type of energy could achieve the same thing ?
What about gamma ray lenses ? Would that do something ... ?
Wow much details in this. I'm first time hear about construction of the neutron generator in this video i was thinking that is classified information :D Great job Scott, fly safe or better fission safe :)
Scott, have you toured the “B” reactor?
Great video! I really enjoyed watching it!
i learn so much from your videos! amazing
I'm a huge fan of this series!
Didnt the need for exact detonation timing help spur the advent of the first germanium transistors?
These videos are really great.
Great video. *REMEMBER KIDS, IF YOU DESIGN SOMETHING TO MOVE YOU CAN ALSO DESIGN IT TO CARRY NUCLEAR WEAPONS*
METAL GEAR?!?
moosemaimer actually i never playd metal gear i invented this sentence.
Around 4:00 you explain that the shorter distances in an implosion device mean that the time between onset and maximum criticality is very short. But how is this achieved? With a shorter 'barrel' I expect lower implosion speed of the pit when being compressed. The compression phase lasts about 5μs?
Fermi also suspected that the electromagnetic pulse from the Trinity explosion would destroy measuring instruments, so they were shielded. Despite the effort a significant number were destroyed. Someone must have been taking notes because it led to experiments like Starfish Prime, and the Soviet K bomb (EMP) test.
Story about one of my old climbing partners
When [my partner] arrived at Los Alamos, his supervisor handed him a pea-size chunk of dull grayish metal and said, This is the world's supply of plutonium. I m going to lunch; please brief me on its metallurgical properties when I get back. [He] pondered his task, then put the pellet on an anvil and smacked it with a hammer, and later reported to his supervisor that it was malleable. As he recounted later, fortunately it was very impure plutonium; otherwise it would have pulverized and contaminated the entire building.
That's just one of his after dinner tales about being on the cutting edge.
Any chance we could get a follow up video/series on the use of nuclear in Space (past, present and future)?
Again, I've read what I thought was a lot of the publicly available literature around these devices, but I'm clearly missing huge chunks, as I'd never even heard of the efforts for Thin Man. What are your major references?
Yes, just a few videos more and i can finally begin my world domin.. i mean world science... fair... project thing!
The cast of Galaxy Quest is coming to retrieve the Beryllium Sphere!