"What Happens in a Bomb Blast?" is based on NUKEMAP created by Alex Wellerstein, a historian of nuclear weapons and an Assistant Professor of Science and Technology Studies at the Stevens Institute of Technology. Data on blast size calculations and associated casualties is provided by Wellerstein's application.
Please note that these casualties numbers are not definitive, but meant to be evocative of the effects."
> "If you take, say, fifty H-bombs in the hundred megaton range and jacket them with Cobalt-Thorium G, when they are exploded they will produce a doomsday shroud. A lethal cloud of radioactivity which will encircle the earth for ninety-three years!" —AdS
In most developed nations, with any major incident emergency services will rush to the site, and victims rushed to hospital.
In a nuclear blast (in densely populated area like a city), this is different:
Emergency services themselves will be taken out (as well as hospitals, energy infrastructure, most comms, perhaps many roads too), and in any case the # of victims (dead or alive) will be so enormous that first responders (coming from neighboring cities) will be completely overwhelmed. To the point where their arrival on-scene makes no difference whatsoever.
Read: if you'd ever find yourself victim of a nuclear blast, you're on your own. Probably lucky if you die instantly.
> Read: if you'd ever find yourself victim of a nuclear blast, you're on your own. Probably lucky if you die instantly.
Emphasis on "lucky if you die instantly."
There seems to be this pervasive belief about nuclear weapons that they just wink people and cities out of existence, and all the millennial and Gen-Z nihilists blithely proclaim "Oh, I live in [XYZ City], I'm screwed anyway haha I'll just get vaporized!"
The "instant death" radius is a LOT smaller than most people realize (~1/2 mile radius for a 10KT warhead)[1] (shown in link as "Severe Damage" radius").
If you seriously believe there's a threat of a nuclear detonation affecting you, don't expect to just painlessly disappear. Be prepared.
I don't necessarily expect it to get better attention. I did intentionally caveat that with "If you seriously believe there's a threat".
That said, I heard a line in the fantastic Kurzgesagt video[1] that said something along the lines of "A nuclear detonation is the worst parts of an earthquake, tornado, and wildfire all at the same time"
It stands to reason, then, that being prepared for each of those disasters will leave you significantly more well off in the unlikely event of "the big one".
Also The War Game from 1966 by Peter Watkins. Was commissioned by the BBC to prepare the public for a nuclear strike, but was then not televised as "the effect of the film has been judged by the BBC to be too horrifying for the medium of broadcasting". Went on to be considered one of the best British documentaries of all time, and one of the most realistic depictions of the effects of a nuclear strike on a populace.
I live near an airport that is very likely a major target. My plan in the event I am aware something is kicking off is to get on a bicycle and get as close as I can. Hoping to get vaporized by the initial blast.
I mean, 10KT is a tiny explosion for modern nuclear weapons. You really only hit that by intentionally dampening the explosion with "dial a yield" weapons.
A better representation would be the W88 at 475KT. That's what's currently used in the Trident SLBMs. And remember that this is an MIRV system with 8 warheads per missile. Yes, the idea is that some of those will be intercepted, but at the end of the day that's still almost 5MT of explosive power per missile dropping down on your city.
Edit: for reference Little Boy and Fat Man were in the 15KT to 20KT range, and for comparison to a modern conflict, about ~50KT of conventional bombs have been dropped on Gaza in the 2023 Israel-Hamas war so far.
> 10KT is a tiny explosion for modern nuclear weapons.
Agreed, but it was the reference I had on hand.
> And remember that this is an MIRV system with 8 warheads per missile. Yes, the idea is that some of those will be intercepted, but at the end of the day that's still almost 5MT of explosive power per missile dropping down on your city.
MIRVs generally aren't dropping 8 identical bombs on one target. Each warhead is independently targeted, as per the acronym.
But larger targets (the 'cities' under discussion here) are allocated whole missiles as a "cluster" as (due to the inverse square law) it's more effective to have multiple middle of the road warheads (in the 0.5MT range) than the single multiple MT warheads when you look at if from the perspective of damage over surface area.
If the target itself is the City itself, then no arguments at all. This is however assuming we're at the "Counter-Value" stage of conflict and past "Counter-Force", so ostensibly you shouldn't be taken by surprise by nuclear bombs falling anyway.
I appreciate your comments, it's always refreshing to have an actual discussion about these topics rather than uninformed fearmongering.
Worth noting that 10kT is 3 orders of magnitude(!) smaller than current warheads. The "instant death" diameter is > 10 miles nowadays. So yea, just a full city :)
> The "instant death" radius is > 10 miles nowadays.
I don't know where you're getting this information.
The "moderate damage" blast radius for the Minuteman missile, currently in service in the US, isn't even 10 miles. The moderate radius for the Russian "Topol"/SS-25 is only ~11 miles.
The blast radius of the Tsar Bomba, the largest nuclear weapon ever detonated, is only ~5 miles for "heavy damage" and just over 12 for "moderate damage".
Nuclear survivability is weird. See Akiko Takakura who survived the Hiroshima bombing with essentially nothing but minor cuts, bruises, and burns (requiring minimal medical intervention) due to the pressure wave and heat despite being less than 1/4 mile (300m) from the center of the Little boy explosion and well within the supposed "lethal range".
What she had going for her was that she was inside a reinforced concrete structure (in the lobby of the bank of japan) and not standing directly near any windows or doorways. That she wasn't crushed or injured by damage to the structure was the true stroke of luck. The people who were inside and away from windows or doors were largely safe from the unique threats of the bomb (fire, radiation, pressure wave) but were still subject to the extreme lethality of being inside a large stone or concrete building that has been largely destroyed by a bomb.
Also she limited her exposure to radiation contamination by getting out of the city ASAP and not drinking the contaminated water. As a result she didn't even suffer radiation poisoning I believe.
With modern knowledge of nuclear attacks, the survivability seems a lot better. If you happen to be in a good, sturdy concrete building (which many are nowadays) at the time of the blast and you don't succumb to mechanical trauma that renders you unable to escape, your odds are quite good if you follow some basic rules:
1. Cover your airways with a mask or at least a rag to reduce dust and particle inhalation.
2. Avoid drinking or eating from unsealed sources where possible. Doubly so for uncovered sources. i.e. bottled water (or anything else sealed) is best. Liquid in an unsealed container is OK even if it isn't ideal and water from open bodies of water or the rain is very very bad.
3. Get out of the immediate disaster area and find a gathering point for medical attention, evacuation, and relocation.
4. Maybe keep some iodine tablets on you to help protect your thyroid (however this is really only a concern for reactor failures and only minimally so for bombings). Take within less than 4 hours and once every 24 hours after that.
If you are in a good position at the time of the blast and you can do those big 3, you have really, really good odds for survival. If you are lucky enough to be able to check box #4 as well that's just a nice bonus.
The Hiroshima bomb, which killed about 70,000 to 80,000 people instantly, was relatively small compared to today's standards. Currently, the most likely threat to a major Western city is from a Russian ICBM. On average, a Russian ICBM warhead has a yield of about 400 kilotons, which is approximately 26 times more powerful than the Hiroshima bomb. While survival in a strong concrete building, such as a bank, is possible, it's important to consider how many people in a city are actually in such fortified structures at any given time. Realistically, a very small percentage of the population would be in such strongholds during an attack. But okay, I have a few iodine tablets in the cupboard.
While yes modern weapons have higher yield, the point still generally holds the same. If you are in a heavy concrete structure, you actually have pretty decent odds. Now what access people have to that depends on where they live.
From my experience on the east coast, a lot of the office buildings, etc in the DMV are mid 20th century brutalist concrete structures. So like even if you were in DC proper, your odds are surprisingly good as long as you are inside a building or in a metro station.
My point wasn't so much that it's easy to survive. It's very much not. However it's not the guaranteed death a lot of people assume. Rather to quote, it's an earthquake, a tornado, and a wildfire all in one (plus radiation). If you are inside you lose the risk of radiation from the blast so now you just have to contend with the threat of 3 natural disasters at once. So if where you work is well suited for safety from a fire, from a tornado, and from an earthquake, you'll probably be in a reasonably safe space.
We both agree that there's a chance of survival. However, an unresolved question remains: is it really better to survive, or would it have been better to have died instantly? If most of my friends and family have died, then I would rather chose the latter.
This is complete false. If you duck and cover and stay inside to avoid fallout you stand an excellent chance of survival. Many hospitals are thick concrete buildings with high blast survivability.
From what I've been reading up to a degree, you want to be in a windowless, low-airflow situation for a day or two so the nuclear particles in the air can settle down. It's not radiation free at that point, but you're mostly dealing with radioactive dust settled on the ground. So walking carefully, wearing a mask or cloth over your nose and trying to keep outside dust outside and not take it inside is a decent thing.
And from there the priorities would be water, food and clearing roads, as controversial as that sounds to "keep the dust down". I live in a city, and my best chance at survival once basics are met is to ensure supplies and emergency vehicles can move. If those don't exist anymore, it's questionable chances anyway, so it's better to ignore that.
It depends if it's a single rogue detonation. Then there is hope federal government and even neighboring municipalities could rush in to help. But if we're talking global war with all major popular centers targeted, yeah that's a whole different situation.
i wonder what engineering breakthroughs would be required to build a typical single staged implosion style nuclear weapon with the explosive yield of your typical fire cracker. The pit would be very very tiny and then the HE lensing and detonation circuitry would also have to be very tiny. Assembling it would be harder than assembling the movements in a watch I bet.
There's this thing called "critical mass". Below that, you do not get an explosion, and no engineering breakthrough is going to change that. Per Wikipedia, the smallest critical mass is 2.73 kilograms, for Californium 252.
For that small a yield, you'd want just barely more than the critical mass. But:
1. The yield is probably a very sensitive function of the mass. It's going to be hard to get the yield to be both greater than zero and less than, say, a hand grenade.
2. You need explosives to make the implosion happen. Those explosives will almost certainly themselves have yield higher than a firecracker.
Critical mass is a function of neutron absorption cross section, neutron emission (during fission) properties, neutron reflection rates, and density.
Those critical mass numbers are assuming either STP or ‘not abnormally insane’ density levels and little to no neutron reflectivity or moderation.
But production nuclear weapons already get below what we’d consider critical mass by using density improving tricks (with the explosive lenses), neutron reflectors, initiators, etc.
Still, anything less than a kg would require some truly amazing tricks, and ‘firecracker’ sized would be likely microgram sized fissile material samples. Which yeah, good luck.
My guess would be so much that the actual criticality event would be caused by the gram of plutonium smashing into the surface of the resulting TNT neutron star at some high fraction of c.
Edit: found this nice write up on Wikipedia [https://en.m.wikipedia.org/wiki/Tamper_(nuclear_weapon)#CITE...] which refers to some papers/books which appear to show that theoretically, with the right reflector/tamper, up to an 8 fold reduction in critical mass is possible. Which would, I guess, make Plutonium’s critical mass (uncompressed) go from 11kg to 1.375 kg.
Throw in the neutron amplification effects of beryllium with high radiation exposure, hyper compression using some of the new super-high-detonation velocity chemical explosives, and I’d bet there are production nukes out there with sub-kg plutonium pits.
Cool beans. Probably still in the 900g range though.
too far below critical mass, unless we’re talking ‘hyper compressed collection of 5-6 digit number of uranium/plutonium atoms’
Which at the point you’re using hohlraums and igniting the collection with petawatt class lasers, I’m not sure ‘firecracker’ levels of measurements have any relevance anymore.
If you're interested in learning more about the level of damage caused by various nuclear weapons, the site NUKEMAP (https://nuclearsecrecy.com/nukemap/) provides a much more detailed set of parameters.
I think that most people do not understand that when a bomb or multiple bombs go off, that 99% of the people will survive in a specific area or country. The only problem is that total chaos got unleashed. Lawless period starts where food and water are scarse. Within 6 months 50% of the population is starved to death, murdered or enslaved by tribes of violent people.
Threads, mentioned elsewhere, is a good cure for hoping to survive a major nuclear exchange.
The first (IIRC) episode of Burke’s Connections is also pretty good for this. The exploration of how dependent we are on electricity and petroleum fuel, and how fast things would get very, very bad if the power simply went off and didn’t come back on, even for folks we think of as being pretty self-sufficient like farmers (“suppose they do have great-grandfather’s plow buried somewhere in the barn, and escaped a dozen other ways things could already have gone lethally wrong within the first year—do they have oxen? Draft horses? No, almost nobody has those anymore” or words to that effect). A largish nuclear exchange would turn the power off and it’d be off for a while. On top of all the direct damage from the bombs.
(The broader point of that episode is that this is basically what we’ve always done: develop new technology, then use it to increase our population such that most of us would die if that tech vanished, starting with the plow, then irrigation, et c; by the mid 20th century we’d reached that point with electricity and petroleum products)
I wonder if I should buy a cabin or chalet in remote Canadian areas. It's time to learn camping, hunting and other survival skills! I should also hoard some medical supplies and hopefully get some prescription medicines. One annoyance is that it's too hard to get prescription medicines and virtually impossible to learn injection (and purchase injectable medicine) if you don't go to a school. Oh, don't forget about radios, batteries, gasoline, etc.
Hopefully everything calms down in a couple of weeks and (what's left of the government) comes out to find survivors.
I'd be vaporized on the spot before I knew it. That's why I hope Putin's missiles are precise enough to hit NATO. I should be able to see it, even for a moment.
68 comments
[ 3.4 ms ] story [ 125 ms ] threadPlease note that these casualties numbers are not definitive, but meant to be evocative of the effects."
We regret to inform you that..."
Con: organ liquification and agonizing death.
A toss up really.
In a nuclear blast (in densely populated area like a city), this is different:
Emergency services themselves will be taken out (as well as hospitals, energy infrastructure, most comms, perhaps many roads too), and in any case the # of victims (dead or alive) will be so enormous that first responders (coming from neighboring cities) will be completely overwhelmed. To the point where their arrival on-scene makes no difference whatsoever.
Read: if you'd ever find yourself victim of a nuclear blast, you're on your own. Probably lucky if you die instantly.
Emphasis on "lucky if you die instantly."
There seems to be this pervasive belief about nuclear weapons that they just wink people and cities out of existence, and all the millennial and Gen-Z nihilists blithely proclaim "Oh, I live in [XYZ City], I'm screwed anyway haha I'll just get vaporized!"
The "instant death" radius is a LOT smaller than most people realize (~1/2 mile radius for a 10KT warhead)[1] (shown in link as "Severe Damage" radius").
If you seriously believe there's a threat of a nuclear detonation affecting you, don't expect to just painlessly disappear. Be prepared.
[1] https://remm.hhs.gov/zones_nucleardetonation.htm
Why do you think a nuclear blast (statistically far less likely) is going to get any better attention?
That said, I heard a line in the fantastic Kurzgesagt video[1] that said something along the lines of "A nuclear detonation is the worst parts of an earthquake, tornado, and wildfire all at the same time"
It stands to reason, then, that being prepared for each of those disasters will leave you significantly more well off in the unlikely event of "the big one".
[1] https://www.youtube.com/watch?v=5iPH-br_eJQ
https://en.wikipedia.org/wiki/The_War_Game
Can be watched here: https://archive.org/details/TheWarGame_201405
A better representation would be the W88 at 475KT. That's what's currently used in the Trident SLBMs. And remember that this is an MIRV system with 8 warheads per missile. Yes, the idea is that some of those will be intercepted, but at the end of the day that's still almost 5MT of explosive power per missile dropping down on your city.
Edit: for reference Little Boy and Fat Man were in the 15KT to 20KT range, and for comparison to a modern conflict, about ~50KT of conventional bombs have been dropped on Gaza in the 2023 Israel-Hamas war so far.
Agreed, but it was the reference I had on hand.
> And remember that this is an MIRV system with 8 warheads per missile. Yes, the idea is that some of those will be intercepted, but at the end of the day that's still almost 5MT of explosive power per missile dropping down on your city.
MIRVs generally aren't dropping 8 identical bombs on one target. Each warhead is independently targeted, as per the acronym.
Yes, smaller targets might get one RV.
But larger targets (the 'cities' under discussion here) are allocated whole missiles as a "cluster" as (due to the inverse square law) it's more effective to have multiple middle of the road warheads (in the 0.5MT range) than the single multiple MT warheads when you look at if from the perspective of damage over surface area.
I appreciate your comments, it's always refreshing to have an actual discussion about these topics rather than uninformed fearmongering.
Edit: radius -> diameter
I don't know where you're getting this information.
The "moderate damage" blast radius for the Minuteman missile, currently in service in the US, isn't even 10 miles. The moderate radius for the Russian "Topol"/SS-25 is only ~11 miles.
The blast radius of the Tsar Bomba, the largest nuclear weapon ever detonated, is only ~5 miles for "heavy damage" and just over 12 for "moderate damage".
src: https://nuclearsecrecy.com/nukemap/
What she had going for her was that she was inside a reinforced concrete structure (in the lobby of the bank of japan) and not standing directly near any windows or doorways. That she wasn't crushed or injured by damage to the structure was the true stroke of luck. The people who were inside and away from windows or doors were largely safe from the unique threats of the bomb (fire, radiation, pressure wave) but were still subject to the extreme lethality of being inside a large stone or concrete building that has been largely destroyed by a bomb.
Also she limited her exposure to radiation contamination by getting out of the city ASAP and not drinking the contaminated water. As a result she didn't even suffer radiation poisoning I believe.
With modern knowledge of nuclear attacks, the survivability seems a lot better. If you happen to be in a good, sturdy concrete building (which many are nowadays) at the time of the blast and you don't succumb to mechanical trauma that renders you unable to escape, your odds are quite good if you follow some basic rules:
1. Cover your airways with a mask or at least a rag to reduce dust and particle inhalation.
2. Avoid drinking or eating from unsealed sources where possible. Doubly so for uncovered sources. i.e. bottled water (or anything else sealed) is best. Liquid in an unsealed container is OK even if it isn't ideal and water from open bodies of water or the rain is very very bad.
3. Get out of the immediate disaster area and find a gathering point for medical attention, evacuation, and relocation.
4. Maybe keep some iodine tablets on you to help protect your thyroid (however this is really only a concern for reactor failures and only minimally so for bombings). Take within less than 4 hours and once every 24 hours after that.
If you are in a good position at the time of the blast and you can do those big 3, you have really, really good odds for survival. If you are lucky enough to be able to check box #4 as well that's just a nice bonus.
https://dsa.no/en/preparedness/taking-iodine-tablets-in-the-...
From my experience on the east coast, a lot of the office buildings, etc in the DMV are mid 20th century brutalist concrete structures. So like even if you were in DC proper, your odds are surprisingly good as long as you are inside a building or in a metro station.
My point wasn't so much that it's easy to survive. It's very much not. However it's not the guaranteed death a lot of people assume. Rather to quote, it's an earthquake, a tornado, and a wildfire all in one (plus radiation). If you are inside you lose the risk of radiation from the blast so now you just have to contend with the threat of 3 natural disasters at once. So if where you work is well suited for safety from a fire, from a tornado, and from an earthquake, you'll probably be in a reasonably safe space.
And from there the priorities would be water, food and clearing roads, as controversial as that sounds to "keep the dust down". I live in a city, and my best chance at survival once basics are met is to ensure supplies and emergency vehicles can move. If those don't exist anymore, it's questionable chances anyway, so it's better to ignore that.
See https://www.youtube.com/watch?v=ybSzoLCCX-Y&t=105s
Lagniappe: https://www.youtube.com/watch?v=mTck2RnpPy4
https://www.newyorker.com/magazine/1946/08/31/hiroshima
For that small a yield, you'd want just barely more than the critical mass. But:
1. The yield is probably a very sensitive function of the mass. It's going to be hard to get the yield to be both greater than zero and less than, say, a hand grenade.
2. You need explosives to make the implosion happen. Those explosives will almost certainly themselves have yield higher than a firecracker.
Those critical mass numbers are assuming either STP or ‘not abnormally insane’ density levels and little to no neutron reflectivity or moderation.
But production nuclear weapons already get below what we’d consider critical mass by using density improving tricks (with the explosive lenses), neutron reflectors, initiators, etc.
Still, anything less than a kg would require some truly amazing tricks, and ‘firecracker’ sized would be likely microgram sized fissile material samples. Which yeah, good luck.
My guess would be so much that the actual criticality event would be caused by the gram of plutonium smashing into the surface of the resulting TNT neutron star at some high fraction of c.
Edit: found this nice write up on Wikipedia [https://en.m.wikipedia.org/wiki/Tamper_(nuclear_weapon)#CITE...] which refers to some papers/books which appear to show that theoretically, with the right reflector/tamper, up to an 8 fold reduction in critical mass is possible. Which would, I guess, make Plutonium’s critical mass (uncompressed) go from 11kg to 1.375 kg.
Throw in the neutron amplification effects of beryllium with high radiation exposure, hyper compression using some of the new super-high-detonation velocity chemical explosives, and I’d bet there are production nukes out there with sub-kg plutonium pits.
Cool beans. Probably still in the 900g range though.
too far below critical mass, unless we’re talking ‘hyper compressed collection of 5-6 digit number of uranium/plutonium atoms’
Which at the point you’re using hohlraums and igniting the collection with petawatt class lasers, I’m not sure ‘firecracker’ levels of measurements have any relevance anymore.
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The first (IIRC) episode of Burke’s Connections is also pretty good for this. The exploration of how dependent we are on electricity and petroleum fuel, and how fast things would get very, very bad if the power simply went off and didn’t come back on, even for folks we think of as being pretty self-sufficient like farmers (“suppose they do have great-grandfather’s plow buried somewhere in the barn, and escaped a dozen other ways things could already have gone lethally wrong within the first year—do they have oxen? Draft horses? No, almost nobody has those anymore” or words to that effect). A largish nuclear exchange would turn the power off and it’d be off for a while. On top of all the direct damage from the bombs.
(The broader point of that episode is that this is basically what we’ve always done: develop new technology, then use it to increase our population such that most of us would die if that tech vanished, starting with the plow, then irrigation, et c; by the mid 20th century we’d reached that point with electricity and petroleum products)
Thanks for bringing that show up, and your comment.-
That show is a masterpiece.-
Hopefully everything calms down in a couple of weeks and (what's left of the government) comes out to find survivors.
Unfortunately I live near Paris and an explosion there would mean that I would suffer with all the consequences without dieing on the spot.