#HydrogenBombs #Fallout #NuclearTesting #RadiationExposure #FissionBomb #FusionBomb
When it comes to hydrogen bombs, the question of fallout is one that often sparks curiosity and concern. Many people wonder if these powerful weapons produce fallout and what the potential effects might be. In this article, we will delve into the topic of hydrogen bomb fallout to provide a comprehensive understanding of the subject.
### Understanding Hydrogen Bombs
Before we tackle the issue of fallout, let’s first establish what a hydrogen bomb actually is. Hydrogen bombs, also known as thermonuclear bombs, are a type of nuclear weapon that derives its destructive power from nuclear fusion. Unlike fission bombs, which rely on the splitting of atomic nuclei, hydrogen bombs use fusion to release an immense amount of energy.
### Fallout Basics
Fallout refers to the radioactive particles that are dispersed into the atmosphere following a nuclear explosion. These particles can be carried by wind and air currents, spreading over large areas and posing a threat to human health and the environment. The presence of fallout is a significant concern in the aftermath of nuclear testing or warfare.
### Fallout from Hydrogen Bombs
Now, let’s address the question at hand: do hydrogen bombs produce fallout? The answer is yes, they do. While hydrogen bombs are primarily powered by fusion reactions, they also typically contain a fission bomb in the secondary stage. This fission bomb is responsible for initiating the fusion reaction and amplifying the explosive force of the hydrogen bomb.
### The Role of the Fission Bomb
The fission bomb in the secondary stage of a hydrogen bomb serves two primary purposes:
1. Triggering the Fusion Reaction: The fission bomb is designed to create the extreme temperatures and pressures needed to initiate the fusion process, where isotopes of hydrogen combine to release massive amounts of energy.
2. Generating Fallout: As a byproduct of the fission process, radioactive particles are produced. These particles can contribute to the overall fallout resulting from a hydrogen bomb explosion.
### Dispersion of Radioactive Particles
Following the detonation of a hydrogen bomb, the radioactive particles produced by the fission bomb can indeed contribute to fallout. However, the tremendous force and energy released by the fusion bomb may disperse these particles over a larger area compared to a fission bomb explosion alone. This dispersion can lead some to believe that the fallout from a hydrogen bomb is reduced or less concentrated.
### The Impact of Fallout
It’s important to note that while the dispersion of fallout may dilute its concentration in a specific area, the overall impact of radioactive particles remains a significant concern. Exposure to radioactive fallout can lead to a range of health issues, including increased risk of cancer, genetic mutations, and long-term environmental contamination.
### Conclusion
In conclusion, hydrogen bombs do indeed produce fallout, primarily due to the presence of a fission bomb in the secondary stage. While the tremendous energy released by the fusion reaction may disperse radioactive particles over a larger area, the potential impact of fallout on human health and the environment should not be underestimated. It’s crucial to continue researching and understanding the effects of nuclear weapons and fallout to mitigate their potential harm.
Yes they do produce fallout. The most important difference between an Atomic Bomb (fission) and a Hydrogen Bomb (fusion) is simply efficiency. Fusion produces far more energy relative to its fuel than fission, by as much as 1000x.
Fusion also produces somewhat more ionizing radiation relative to the actual heat and explosive force so it kills people while doing less damage to buildings and other infrastructure but the reason it produces less fallout and lingering radiation is because there’s much much less radioactive material required to produce a comparably deadly blast.
I will break this down in two parts. First the trigger (primary) and second the hydrogen bomb (secomdary) part.
The “spark” primary to the hydrogen bomb is an atomic bomb it consists of either enriched uranium or plutonium (or a mix) and splits atoms giving off energy. You need this oo generate tremendous heat and pressure.
The “plug” secondary is the cylindrical part, it consists of a radiation case, some foam or plastic and a some hydrogen. There also is uranium to first be energized by x rays then emit neutrons. The neutron combines with the hydrogen and helium is formed. So a pure fusion weapon does not have plutonium and only creates helium… but it doesn’t exist because the secondary needs the pressure and heat of the sun to fuse elements. As it fuses and becomes helium it gives off tremendous energy.
Yes. Fallout mostly doesn’t come from the bomb, it comes from neutrons the bomb releases interacting with material thrown up by the explosion.
A well working fission bomb already have very little fallout. If the device works as designed then all fission material gets converted to stable isotopes. It is when the detonation does not go as planned that you get large amounts of half-fissioned material that forms the radioactive fallout. This is generally why some test sites became contaminated while others were not.
I am not quite sure what effects a fusion reaction have on this though. I would presume that the fusion detonation could eliminate some of the fallout from the fission reaction by bombarding it with neutrons. It is also not quite right that fusion reactions have no fallout. Similar to a fission bomb in a perfect scenario all the material end up as stable helium but where things are not perfect you can get radioactive tritium or isotopes of lithium and other elements. And the neutrons can create a lot of radioactive elements in the material around the bomb.
In any way the amount of fallout from a hydrogen bomb compared to its yield is a lot lower, almost negligible. But it does suffer from the same issue as atom bombs in that failed tests can still have considerable fallout.
It produces more fallout. A hydrogen bomb is two bombs in one. The first is a plutonium device that acts as a spark to create massive amounts of heat and pressure quickly to kick off the second part, which is the fusion of the hydrogen. And that hydrogen part usually uses a lot of uranium as part of its construction. So, even though much of the explosive energy comes from the fusion of hydrogen, there is still fallout produced from the fissioning of uranium and plutonium.
They can be relatively clean(never perfectly clean), or extremely dirty. Depends on detonation altitude and what the secondary tamper is made out of. The fusion releases a lot of neutrons, and this can be used to split depleted uranium, which increases yields but is also very dirty.
With an airburst the contamination is only the material the bomb is made of, and it’s so finely divided that it takes weeks to fall out of the atmosphere, by which point the worst isotopes have already decayed and the rest have been diluted. With a ground level detonation, a lot of relatively heavy material gets contaminated and falls out of the air nearby, posing an immediate hazard.
Fall Out is produced, not only by the explosion, but by the things the explosion destroys like buildings, ground, fluid, etc… They become dust and steam. These things mix with the radiation and the shock wave distributes it.
Fusion bombs aren’t just hydrogen isotopes fusing..
To start with the current way we can start the fusion reaction is to use a fission atomic bomb. So you have a uranium/plutonium bomb in the assembly just to get the thing going.
Following – in a lot of hydrogen bombs the fusion stage is also used to generate a sea of fast moving neutrons that is absorbed by fissile material surrounding the fusion core (and enabling the fusion core to fuse) and results in even more fission than you’d get from a plain fission bomb that blows itself apart before all that much fission can take place.
So yes, hydrogen bombs very much cause fallout.
Simple answer, yes. A hydrogen bomb contains a regular fission bomb inside it as the trigger to start the fusion reaction.
More complicated answer, not as much. A modern hydrogen bomb has a much higher yield but only the fission primary produces fallout and that fission primary is extremely small because modern designs are more efficient compared to designs from the 40s so you’ll end up with maybe 10x less fallout and 10x more explosive power.
A pure fusion bomb would produce less fallout per unit yield than a fission only bomb but it would still produce some as others have noted fusion bombs contain a primary fission explosion that is required to set off the fusion reaction.
In the real world, most fusion bombs are actually fission-fusion-fission bombs where a primary fission explosion with fissile martials (U-235 or Pu-239) ignites a fusion reaction. The extremely high energy neutrons of the fusion reaction subsequently set off a tertiary U-238 tamper to an enormous fission explosion. Since U-238 is not fissile, you can put as much of it in the bomb as you want without a risk of it reaching critical mass.
The Tsar bomb (the largest manmade explosion ever) had a yield of 50 megatons of mostly fusion. But the original design had a U-238 tamper that would have increased the yield to over 100 megatons but would have produced an enormous amount of fallout. Before the test it was decided to remove the tamper to limit the fallout.
The majority of the yield from most hydrogen devices comes from fission of the uranium tamper. They just include fusion, they’re not primarily fusion.
They still produce fallout, and likely a lot more than some pure fission bombs. It’s possible to reduce fallout (Tsar Bomba detonated without the tamper and was something like 97% fusion), but it would dramatically reduce the yield (50% in this case).
i am not a nuclear physicist so my understanding may be wrong.
a hydrogen bomb is essentially a VERY short lived star stored in a bomb (which is kind of interesting if you ignore the horror of nuclear war) that reaction DOES produce radiation and some fallout but it’s actually a fairly efficient reaction. where most of the fallout in a a hydrogen bomb comes from is the detonator which is a fission bomb that is used to start the fusion reaction which is significantly less efficient.
if you just used the fission detonator as a bomb itself (ie an atomic bomb) you’ll produce a similar amount of fallout but over a smaller area (since the blast wave won’t physically disperse the material as much)
So a hydrogen bomb has a fission section which “ignites” the fusion section, but the fusion section is wrapped in a heavy metal. Sometimes this is natural uranium which fissions as well and produces lots of radioactive isotopes plus a lot of the power released by the bomb.Â
There may be lower fallout designs in use now that don’t have the same wrapper and use radiation instead of blast pressure to kill people without as much infrastructure damage.Â
There have also been designs that produced extra fallout but these probably haven’t been built.Â
One thing to note is that a thermonuclear bomb needs to use Plutonium or Uranium as the initial stage to produce the heat and pressure needed to start the fusion process of the lithium/hydrogen secondary stage. A significant percentage of the total bomb yield comes from this first ‘atomic bomb’ stage of the weapon. When they detonate there isn’t 100% efficient fission, so a lot of the uranium/plutonium atoms are scattered, as well as a lot of the fission byproducts that also emit significant radiation risks.
Just a note.
No bomb is 100% fusion. You need a fission reaction to start the fusion reaction. Most bombs aim for a 50/50 fission/fusion mix. Even then, only about 30-40% of the material is actually consumed by either reaction.
And that material that isn’t used up has to go *somewhere*. Which means some amount of fallout from the bomb itself. Now, a bomb can also turn debris in the area radioactive, and that can get sucked up into the atmosphere and also become fallout. Although with a fairly short half-life compared to the material ejected from the bomb itself. But, either way, it is not good to be around it.
TL;DR, there’s an option in an h-bomb’s design to get a massive fission reaction and nearly double the yield for free, so half the yield of most H-bombs is actually a fission reaction, because why not? But this means that nearly half the yield is fission, more than is possible with just an atom bomb, and that means a LOT of fallout.
To elaborate: Hydrogen bombs are composed of two parts: A primary and a secondary. The primary is just an atom bomb, while the secondary is where the fusion occurs.
The exact details of how a hydrogen bomb works are not publicly known, and much of what we know is pieced together from declassified information that has come out over the years. But what we do know is that there is at least 1 fissile component in the secondary which helps drive the fusion (a plutonium « spark plug »). That alone is a small amount compared to the total yield of the fusion, so in theory if you just have that, plus the fact that you are using just one small atom bomb as the primary, means the amount of radioactive isotopes produced is less than the equivalent yield in atom bombs.
But this is the real kicker: The secondary is made of, on the outside, of a heavy metal, which absorbs radiation from the primary and heats up and expands. This creates heat and pressure for the fusion fuel in the middle that drives the fusion reaction. This is called the tamper, and you can make this out of an inert material like lead, but you can also make it out of depleted uranium (left over waste material from enriching uranium to create the A-bomb). If you’re making these bombs, you probably have a lot of DU lying around anyway. And as a bonus, the thermonuclear fusion process is enough to make the DU tamper undergo fission as well.
Since depleted uranium is much more stable than enriched uranium, there is way more depleted uranium in the tamper than would be feasible to put the equivalent in enriched uranium in an atom-bomb before the enriched uranium goes critical. The tamper undergoing fission is can produce a yield nearly as high as the fusion reaction itself.
Now if you’re developing a hydrogen bomb, are you going to leave half the potential yield, for free, on the table? I think not.
But because this last reaction is an absolutely massive fission reaction, it generates an incredible amount of radioactive isotopes. Coupled with the fact that higher yields produce diminishing returns in terms of destructive power as a lot of that energy gets wasted, meaning that more yield is required for 1 hydrogen bomb than the combined yield of multiple atom bombs, and hydrogen bombs can produce just as much fallout as atom bombs for the same amount of destructive power.
That isn’t to say that you can’t create a « cleaner » bomb by sacrificing half the yield, however. This is exactly what was done for the Tsar Bomba test; the original 100 MT yield was deemed way too much and they swapped the DU tamper out with a lead tamper, resulting in a cleaner, ~55 MT bomb. But that was a special case where they needed to reduce the yield; normally, you want the most bang for your buck, and if you want a lower yield then you start off with a smaller bomb. Now compare this with Castle Bravo, a ~13 MT bomb that created the worst radiological disaster ever until Chernobyl. The Castle tests firmly put to bed the idea that H-bombs, at least the designs commonly used, are in any way « clean ».
Yes, absolutely. A hydrogen bomb is just a regular fission bomb with extra stuff (the fusion secondary), and the point of the extra stuff is mostly to generate a lot more neutrons to trigger even more fission in the fission core. The fission of U235 is what produces Cs-137 which is the most dangerous fallout product from a nuclear bomb, and a fusion bomb just produces more U235 fission than a fission bomb would on its own.
The Castle Bravo hydrogen bomb test was a massive fallout disaster that ended up killing some Japanese fishermen that were downwind from it. The scientists in charge of the test miscalculated the yield due to unknown fusion properties of lithium isotopes. So yes, if the fireball hits the ground, whether through miscalculation or an intentional ground burst, it’s going to suck up whatever is on the ground and mix it with all the nasty radioactive fission products from the bomb.
The Tsar Bomba test was relatively “clean” because the fireball didn’t hit the ground. The nasty fission products are lofted into the upper atmosphere, distributed over the globe and have a lot more time to decay before they fall back to the ground. Partially because the bomb was detonated so high in the first place, Partially because its massive yield lofted the debris cloud so high and Partially because the fission products didn’t have heavier bits of vaporized rock/soil/people/etc to drag them back down before they decayed or disbursed.
If you line the bomb with led it will reduce the fallout. If you lace it with cobalt you will absolutely end the world. It’s that versatile.
The Russian 50megatonne tzar bomba was lined with lead to reduce the fallout. If they literally replaced lead with cobalt it would have irradiated 1/2 Russia and Europe for 1000 years.
Ok so the top comment is saying things both correct and incorrect.
Fusion based bombs do not create dangerous daughter nuclei (on purpose) because they burn deuterium and tritium (via lithium) to produce very energetic helium nuclei.
However, in the case-ulam-teller design (Ivy Mike, and other early H-bombs) there is a uranium or plutonium tamper that encases the fusion fuel. This high-Z material reflects neutrons and radiation back into the fusion fuel.
Basically, to create a fusion reaction with a self sustained burn you need excellent confinement of energy. The easiest way to do this is to make the fuel dense enough that neutrons and photons are reabsorbed instead of escaping the system.
So in the CUT H-bomb a traditional fission bomb is set off to increase radiation pressure and heat the fusion fuel, which then begins to fuse until the kinetic pressure is so great that the encasing radiation reflector explodes.
In short, there is a very large amount of fall out from an H-bombs, but considerably less than a fission bomb of the same explosive magnitude.
*I don’t have any knowledge of thermonuclear bomb design past the 60s because that is all classified
This ELI5 is going to turn into an ELI15 but I’m gonna try my best.
H-bombs of high yield are more efficient. H-bombs use less fissile or fusable material over the total energy released, compared to smaller H-bombs and classic A-bombs. This means that less unused material and raw bomb parts are strewn about.
Also, since the bombs are bigger, that material is spread farther distances, and is more or less diluted.
However, this isn’t to say that h-bombs are the least fallout producing weapons we have, they can be quite the opposite if we do something stupid.
A greater factor in fallout generation is burst height. Proximity to the ground can create second hand fallout, i.e., everything that isn’t bomb parts and recondensed fissile materials and fission products. Think soil.
A key example would be the Castle Bravo test. We, the United States, detonated one of the most powerful bombs devised by man, on the ground in an atoll. Uncountable pounds of sand and coral reef were irradiated, vaporized, and it rained radioactive sand snow over half the Pacific for a couple days, killing a bunch of people. That was an H-bomb, it was a very efficient one as well.
Tl;Dr: nukes r bad mkay. don’t do nukes.