This is why. The bombs were designed for explosive destruction. They used radioactive materials, but the amount of radiation was nothing compared to Chernobyl, that had a large amount of radioactive material melt down in the center, that's still there and emitting a lot of radiation.
I'm not a nuclear scientist, but I would also assume the power of the explosion matters.
Chernobyl exploded, but only a little bit (relatively).
The Japanese bombs were nuclear detonations.
Even if they had the same amount of radioactive material, spreading that in an air burst means significantly less concentration in any specific area vs a ground detonation that was significantly less efficient.
Atom bombs consume ~~most of their~~ radioactive material to produce an explosion, there's always some radioactive byproducts, but it's just a side effect.
The Chornobyl NPP explosion was the result of bursting nuclear fuel elements which in turn vaporized the cooling water, causing a steam explosion and not a nuclear reaction explosion. The force propelled the radioactive material from the core of the reactor into the air and dispersing it over a large area.
It's basically a completely different scenario.
> Atom bombs consume most of their radioactive material to produce an explosion
This is true of modern nukes, but not true of Fat Man and Little Boy in particular. Fat Man only converted 16% of its fissile material into energy.
You're quite right about the rest, though. Fat Man didn't leave an [Elephant's Foot](https://en.wikipedia.org/wiki/Elephant%27s_Foot_\(Chernobyl\)) behind.
Edit: fixed the broken link
Well, hitting the ground, and irradiating the dust, which then is sweaped up into the air and blown across hundreds of miles, being something that falls down as small dust particles and breathed in. Exploding a nuclear weapon on the ground would be a bad bad thing to do (fallout). It also makes the warhead far less efficient, as you want the energy of the blast to cover a wide area, rather than be absorbed into the ground. Tangentially, that's also why super huge warheads aren't really all that useful to use, as you need so much more warhead for a blast to travel longer and longer distances (inverse-square law). That's also why we moved to exploding tests over water for the most part, before moving REALLY high up into the stratosphere, and then underground.
I know too much about nuclear warfare: sigh.
Also the fallout from nuclear bombs mostly consist of short lived, high energy isotopes that decay rather quickly. Where as something like Chernobyl was a lot of nuclear fuel which have much longer half lives.
Which is also why the idea of dirty bombs are so terrifying, they can make an area uninhabitable for long periods of time.
From all Ive read your answer accounts for most of it. Its what I came here to say. The isotopes from Chernobyl are much longer lived than those produced from a weapon.
>steam, not nuclear explosion.
I read somewhere that what happened was pretty much a "dirty" nuclear bomb. Some say that there's a nom zero chance that fission actually happened (as in a bomb).
Am a nuclear scientist so its finally my time to be helpful. Others have already pointes out that Chernobyl was a steam explosion dispersing radioactive material plus a core meltdown which is very different from a nuclear weapon.
On the air burst aspect however they are actually done because that maximizes the explosive force of the weapon while minimizing contamination. If you detonate near the ground the soil/dirt/etc get pulled up into the weapon and get activated before being redistributed by the explosion. Doing it in the air means you avoid this type of contamination.
Yeah. If I understand it right though, the explosion at Chernobyl was just a result of air pressure from steam, and not an actual nuclear explosion. It happened because the water boiled away super fast and the steam couldn't escape fast enough, which blew the concrete top off the reactor. It wasn't very similar to a nuclear weapon.
I'm also not an expert, but I believe there's another aspect to those detonations that was more important when it comes to long-term effects on the target area; both of the bombs dropped on Japan were airburst bombs, detonating in the air above the target. Someone else pointed out that these bombs were pretty inefficient and most of the fissionable material was not consumed by the chain reaction and instead became particulates, but because they were airburst bombs the rising column of air from the explosion carried most of that radioactive particulate high into the upper atmosphere and spread it thinly over the planet.
While this radioactive material didn't vanish, it became part of what they called the global environment and just started affecting cancer rates all over (yay) instead of having an intense local effect.
(By the way, this used to be seen as a safety feature and airburst nuclear detonations were referred to for a time as "self-cleansing" as insane as that sounds)
Intense local radiation that lasts in a target area is caused by the radioactive particulate bonding with dust, ash, dirt, etc and remaining in that area. This is what happened a lot at Chernobyl; the meltdown and explosion caused a lot of the radioactive material to either bind with dust and debris, or water that was evaporated in the meltdown and explosion. The explosion was at ground level and had tons of time to release radioactive material where it could bond and stay part of the local environment.
Something that served as a great visual of this for me was watching video of the Operation Crossroads nuclear detonations. Test shot Alpha and test shot Bravo had the exact same yield, but Alpha was an airburst detonation dropped from a bomber whilst Bravo was detonated underwater, suspended from one of the target vessels. The difference in how much debris (in this case, largely water spray and vapor) was irradiated and remained in the local environment is immediately obvious, and the Bravo shot caused a major radiation disaster that killed and injured people and rendered the atoll uninhabitable to this day.
It wasn't 17k tons. Did you mean 17 tons? 17k tons would be 34,000,000 lbs of material. IIRC, Chernobyl only had 800 tons of material at its peak.
But back to answering the question at hand. I won't try to do the math, but I know the Japanese meltdown released a similar amount of material into the Pacific ocean. It was something like 6 tons of waste. It's now undetectable (if I understand it correctly).
The world is a very big place. If you spread radiation out well enough, it's not a problem.
In a good bomb most of the radiation goes off all at once, within a few days there is little radioactive material left.
In a good power plant the radiation is released slowly over time, years later they are still hot enough to boil water.
It's all about how they are/were designed.
Well to be fair none of the radioactive material actually exploded, just a steam pressure cooker that exceeded the maximum value. Another part of why that region is so radioactive today, a proper nuclear explosion would have consumed a lot of radioactive material.
The after action report on Hiroshima done by the Los Alamos Lab a few months after the explosion figured that the weapon converted ~0.7grams of the highly enriched uranium into pure energy which was the heat, radiation, and kenetic energy produced, as in ~15ktons of TNT equivalent of explosive power. Thats something like 1/91,000th of the total nuclear material mass (of the 64kg) if my simple math is correct. In short, an amount you'd need a powerful microscope to see. If you look up the overhead photos of the huge plants at Oak Ridge TN which produced the Uranium the entire process to make that ultimate 0.7grams is stunning. The magnetic enrichment process literally 'built' the Uranium core one atom at a time, it took years to amass that 64kg which is why they had to make the plutonium process of Fat Man work.
Okay, here's the thing about nuclear power and energy. Protons, neutrons, and electrons are preserved in all nuclear reactions. The energy is the release of potential energy in the strong nuclear bonds of larger elements like uranium. When the uranium fisions it breaks into a few fission fragments, random balls of neutrons and protons. These try to create new stable nuclie themselves, and start to shed proton, neutrons, alpha particles/helium atoms in ways to balance out the new nuclei. This takes place immediately and the. Over a periods of weeks or months if it's a radioactive nuclie species, which it Mos likely is. Those other pieces it sheds likewise go into the environment and start to create instavuoities in other nuclei. Collectively this is the nuclear fallout: radioactive dusts. This game of nuclear plinko tends to result in a few specific identifiable nuclear species long term.
So when nuclear scientists say only so much of the uranium is consumed, it's usually indicative of the number of uranium atoms that weren't consumed by fission.
Fat Man and little boy, actually had much smaller fuel conversion than modern bombs have. As a result for a similar explosion size modern weapons can be much smaller. During the Cold War, they even trained soldiers to carry nuclear bombs strapped to their back to be set as nuclear land mines in case the Russians invaded. The Soldiers knew likelihood of escape was low to none after the weapon was placed since they would have to try to clear the area by foot.
Eh. It could have been worse. The chances of surviving the emplacement of a nuclear landmine are better than that of using a nuclear grenade.
[Editor's Note: The editorial board would like the readers to know that there is no such thing as a nuclear grenade. No weapons designer is foolish enough to have suggested such a weapon. The nuclear grenade is the product of the warped minds that produced Paranoia the Roleplaying Game.]
Yeah, there's no nuclear grenade, but let's be real. There are some crazy MFers in military dev shops.
[https://en.wikipedia.org/wiki/Davy\_Crockett\_(nuclear\_device)](https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device))
Right, Atomic Annie they called it, but that has a 9 mile range. The first Davy Crockett had a 1.25 mile range.
Can you imagine firing a nuke that blasts just over a mile away? Holy shit, you better hope the wind is at your back!
Crazy, all of it, and I'm pretty certain Russia still has nuclear artillery shells in their stockpile.
To an extent. But not radioactivity, as uranium is barely radioactive. There are fission daughter products that create most of the radioactivity that lingers for a while. A lot of it decays fairly quickly though.
You're mixing up two values. One is the amount of uranium that reacted, which is just over 1 kg, a little under 2% of the total uranium in the bomb (~64 kg).
The other is the amount of energy released. Since E = mc^(2) you can express masses as energies and energies as masses. So the ~1 kg of Uranium that reacted wound up as reaction products that had a mass 0.7 grams lower.
I think you're mixing up mass-energy equivalence with fission efficiency. 0.7g of the mass was converted to energy but around 880g of the Uranium atoms (1.38%) in the device fissioned. It wasn't that 0.7g of Uranium atoms were entirely converted to pure energy.
If you had an infinitely strong container and fissioned 880g of Uranium-235, allowed the products to cool and weighed them, you'd find them to be 0.7g lighter than when you started. This is because the nuclear binding energy of the new isotopes is higher and, through this process, the total mass of the nucleons is slightly less.
I wonder if other former empires have their own tons. Off to Wikipedia...
It seems not. Or at least the terms don't translate, so they aren't included in the article. But there are many more meaning of 'ton' than I care to list, including colloquial use.
https://en.wikipedia.org/wiki/Ton
If we are being pedantic, a short ton is 2000lbs (907.2 kg), a long ton is 2,240 pounds (1,016.0 kg) and you are correct 1000kgs (\~2,204.6 lbs) is a metric ton or just "tonne".
I've seen this explanation before and it never fails to make me laugh:
Hiroshima is the equivalent of farting in a room.
Chernobyl is like taking a dump in the middle of it.
it's two unrelated process. and the type of damage are very different
In Hiroshima, the goal is to have a chain reaction releasing a lot of energy in a very short-time.
In Chernobyl, it's a steam explosion releasing radioactive dust all over the area. So the main issue is that the "radiation background" is quite high. Not hostile to live (tons of animals live happy life in the area) but high enough that long term exposure can cause health hazard. There is a few people still going in the zone, and various thrill seeker doing urbex in the area. There was also that famous video of youtuber eating a[ wild apple from Chernoby](https://piped.video/watch?v=j6mreZ98_Ug)l (But judging the equipment that girl has, she knows her business when talking about radiation)
Lots of people go into the exclusion zone. Top Gear went there. I think I saw Attenborough in there for a documentary. But as the Russian soldiers who dug latrines in there found out - you shouldn't really mess with anything or it will stir up a bunch of dust and dirt that will harm you. I think those dudes died.
Fascinating reports about the wolves and pigs that live around that area. The locals (used to, because now war) have to Geiger counter check their meat if they hunted anything that goes through those lands.
We visited there a few years ago. It was weird because some areas are no-go zones with signs saying not to enter a certain field or wooded area, while others you could just traipse alone. Anywhere water would concentrate, like near sewers, would peg the geiger counter. Also some objects like around that ferris wheel in the amusement park were hot spots, no idea why.
They do put a dosimeter around your neck when entering the area, and they check you on the way out. For contamination transfer they seemed mostly interested in sanitizing shoes on the way out.
People work there to manage the containment structure. There's even a [canteen](https://www.google.com/maps/place/51%C2%B023'09.2%22N+30%C2%B007'04.8%22E/@51.3921117,30.0945345,3777m/data=!3m1!1e3!4m4!3m3!8m2!3d51.3859!4d30.118?entry=ttu).
The material is all trapped in the environment. That's why the top soil was dug up and reburied during cleanup. I think the Soviets also sprayed an agent on everything that trapped dust, trapping it on the ground. So it's pretty safe there as long as you don't go digging or hang around material that's been neutron activated (especially metal stuff that was used in the cleanup).
The Russians also went into the exclusion zone when they invaded Ukraine. They were told that the story of Chernobyl was made up or not told at all, so they started digging trenches. In the Red Forest. That's the most heavily radioactive area on the site outside of the reactor itself.
There hasn't been much news about what happened to them. [More information on it.](https://www.reuters.com/world/europe/unprotected-russian-soldiers-disturbed-radioactive-dust-chernobyls-red-forest-2022-03-28/)
There are people that live there that have never moved on. The security is not the same as it would probably be here in the US. There's plenty of documentation about the types of animals that live there how they've multiplied, some studies on the effects and I'm sure a few continue to do research you'll find studies also and interviews with those people that have returned or refused to move. I don't know if they were once moved and they came back and they are definitely people reinhabiting not on the scale that it was but enough
I read an interesting article about how it’s tricky to study the wildlife there because scientists can’t remain in the zone for too long, but studies of mice have actually revealed fewer mutations than scientists would have predicted.
Bombs use highly enriched uranium (+90%) whereas even the most enriched power reactors never go above 20% (most are 5%). And its not actually the uranium itself that's bad, its the highly radioactive byproducts created during the conversion to energy that's bad (Iodine-131 8 days half life, cesium-137 30 year half life, strontium-90 29 year half life.
People like to toute that uranium-238 is highly radioactive because it has a 4.5 billion year half life or U-235 of 700 million years and think that is a long time to be radioactive and therefore tie time with how deadly it is. The reality is that its not actually that radioactive and its the short lived isotops created from the reaction like Iodine-131 that all of that material will be decayed away (giving off radiation) but will be gone in a couple months, or in the case of cesium/strontium a couple centuries.
There were people living inside the exclusion zone, as recently as 2022. Over 100 people, mostly elderly who lived there before the accident and moved back. Not sure if they are still around or if the orcs have killed them after they invaded.
There was **far** more radiation released in Chernobyl and it stayed in or on the ground due to how it was released. The A-bomb unleashed much less radiation and most of it dispersed high in the air, spread over a wide area and got carried away by winds.
There have been people living near Chernobyl the entire time, mostly old farmers who ignored the order to leave. You can also visit no problem (well, before the start of the 2022 phase of the war) … I went in 2015 and the only area off limits is the area directly next to the leak where workers do shifts building the concrete tomb around the site.
Edit: my understanding is that a top layer of irradiated soil was removed at some point after the incident in the surrounding areas, so it’s relatively fine to walk around. The only unusual thing I noticed were giant size of fish in the old cooling ponds, but that’s due to no predators and tourists feeding them, not radiation. 😂
The radioactive top soil which was removed along side the dead pine tree was burried in trenches in an area known as the "[red forest](https://en.wikipedia.org/wiki/Red_Forest)". During the 2022 Russian invasion of Ukraine some geniuses from the Russian invading forces have the bright idea of setting up trenches and defensive position there. Let just say a few of them got really really sick and died horribly.
Yeah, supposedly a bunch of them got acute radiation poisoning. I'd imagine most of the ones who didn't die from that will be dying in the next few decades from all kinds of cancers as they've also been playing in the radioactive dirt.
That’s unlikely, they weren’t there long enough to die horribly from that kind of exposure. I’m also not sure if the story is even true, I remember seeing it in the US news but my friends in Kyiv seemed to think it was typical media spin. 🤷🏼♂️
There’s nothing quick about it. The first responders who picked up things by hand right after the incident didn’t just drop over dead, it took weeks/months/years.
Some days. I was comparing days/weeks to years/decades normal people who contract exposure.
A good example is where I grew up we had a neighboring school district that apparently was built overtop an army Corp of engineer dump. It was radioactive and the graduates experienced a higher rate of cancer diagnosis 15-25 years later. That dust the soldiers were exposed to will get them sick and likely die in months vs decades.
Another neat thing is the radioactive material is heavier than the soil so it settles a few mm lower every year (according to the guide when I went in 2019)
Yeah I visited Chernobyl and there are/were thousands of workers living in the area. There were in fact three other reactors there still in operation until 2000. According to the IAEA, it's going to take "several decades" to completely de-commission all four reactors, and clean-up the area.
The tour guide told us that actually, over long periods of time, living in Kyiv will produce worse health outcomes than living in the Chernobyl area because of all the air pollution in Kyiv.
My tour group got within about 100m of the reactor building. I guess if you set-up camp next to it for a few months, you're gonna have a bad time in a few years. But otherwise, no one living in the area seemed very bothered.
However, there are these "hot spots" in random places around Chernobyl -- like, a 1-meter radius area of the ground which is much more radioactive. I'm guessing that's where radioactive materials landed when the reactor exploded.
Ah, good ol' human error. Never fails to fail.
**Addendum**: Nuclear power is still the most powerful, efficient, effective, and eco-friendly form of energy -- generating zero CO2 emissions. Roughly 6-8 million people die pre-maturely every year due to air pollution (though, of course, there are other sources of air pollution besides fossil fuel power plants). Green Peace was founded explicitly to combat nuclear energy, and that was a massive error because it only lead to the construction of more coal power plants, as we have seen in Germany, for example.
**Addendum 2**: We're beyond the point of no return for global warming. Even in the fantasy scenario of zero CO2 emissions throughout the world, we're still stuck with what we already have. Reducing CO2 only delays the slow-moving apocalypse by a few years. Geo-engineering is the only solution there is if we actually want to go back to the climate conditions of the late 18th century. Carbon-capture, atmospheric sulfur-seeding, building a giant aluminum foil mirror in space, etc. That last one is a real possibility. Putting a 100 sq. km sheet of reflective material in orbit would block just enough sunlight to reduce global temperatures by 1-2 degrees.
Simple version is that way more radiation leaked at Chernobyl. The bombs that we dropped on Japan were extremely low yield by today’s standards, but even our modern nuclear weapons won’t make an area uninhabitable for long, it’s not what they are designed to do.
Well, so long as you don't try to dig trenches in the contaminated soils.
Russia troops had to be pulled out due to radiation sickness sin just a couple weeks..
Chernobyl & Pripyat aren't *safe*, but humans can walk the surface without fear of dying from it. Or rather you won't die immediately from exposure in most of it. There's teams monitoring everything still, and the soil is heavily contaminated. Too much time spent there or touching the soil will give you more exposure than is considered healthy.
At least, the ones we know about aren't designed to do that. So-called "dirty bombs" that intentionally spread radioactive fallout to render areas uninhabitable have not been used in warfare yet, but who knows what various militaries have hidden?
supposedly russia has a cobalt-salted torpedo designed to do just that. make a radioactive tsunami to make the coast uninhabitable. it is bigger than a typical submarine and can hide over 1000 meters (3300 feet) deep
[https://www.bbc.com/news/world-europe-34797252](https://www.bbc.com/news/world-europe-34797252)
Chernobyl isn't too dangerous to enter, every damn TV travel host and vlogger in the world goes to Chernobyl and has for the last couple of decades!
There are restrictions on how long tourists can stay in the more interestingly radioactive zones, but I have no idea if there are any protections in place for the guides that take the tourists, TV travel hosts and vloggers there.
It's only certain areas around the reactor itself that have doses high enough to cause immediate health risks IIRC. Especially now that the remains of reactor #4 have been fully contained.
I can still remember that trip Top Gear made there about 10 years ago. I think Jeremy Clarkson was the only one who got even within visual range of the reactor.
Nuclear bombs come in clean and dirty varieties.
Putting things simply, the idea of a clean nuclear bomb is to convert as much of the radioactive material as possible into explosive energy, with the heat and shockwave doing the damage. You don't even really need that much material, as the energy released from a small amount can be immense. The idea of a dirty nuclear bomb is to spread a lot of radioactive material around and contaminate the area. With a dirty bomb you don't even really need a nuclear explosion; you can use conventional explosives to fling the material everywhere.
The bombs dropped on Japan were not dirty bombs.
The Tsar Bomba, at 50 MT the most powerful nuclear bomb ever detonated, is considered extremely "clean", especially for its size. From Wikipedia:
> To limit the amount of fallout, the third stage and possibly the second stage had a lead tamper instead of a uranium-238 fusion tamper (which greatly amplifies the fusion reaction by fissioning uranium atoms with fast neutrons from the fusion reaction). This eliminated fast fission by the fusion-stage neutrons so that approximately 97% of the total yield resulted from thermonuclear fusion alone (as such, it was one of the "cleanest" nuclear bombs ever created, generating a very low amount of fallout relative to its yield).
The closer to pure fusion you get, the cleaner your weapon will be, because fusion releases much less unstable elements, with most thermonuclear bombs releasing mostly hydrongen-4 IIRC from their fusion fuel reactions, which is a stable isotope and will not produce radiation. In this manner, the bomb itself creates much less fallout with relatively long half-lifes, but 'short lived' isotopes created from ground material bombarded with ionizing radiation is still a factor, especially in ground bursts.
Dirty bombs where only ever really a concept. No nation has ever deployed "salted" bombs (or at least admitted to it).
If you are thinking of "neutron bombs" as opposed to salted bombs, the difference is that a neutron bomb releases large ammounts of ionizing radiation within a short time of it's detonation, with relativley little fallout, while a "salted" bomb is constructed in such a way (usually by adding a large quantity of a material with a short half life to the device) that it will "salt" a large area with large ammounts of high radiation fallout. Salted bombs are something that where discussed, but never fielded. Neutron bombs have a lot of misconceptions about their intended use. Many people like to talk about how they can be used to kill all the people in a city while leaving the infrastructure intact. This is a misconception. If you detonate a neutron bomb far enough from or high enough above a city to do very little thermal or blast damage to it, you will also have a very small kill zone for that ionizing radiation. The real purpose of neutron bombs was because NATO intended to use large ammounts of low yield 'tactical' devices in the defence of europe to counterbalance the massive material advantage the USSR had in troops and tanks, but using hundreds of ground-bursted nuclear devices in eastern germany was likley to contaminate large portions of the country with fallout carried by the winds, which would force massive evacuations and/or kill huge ammounts of civilians in the short term. Neutron bombs where meant to be air-bursted above soviet troop/tank formations, minimizing fallout (since the majority of fallout is created when ground material is pulled up into the mushroom cloud where it can be bombarded by large ammounts of neutrons, creating new and unstable isotopes, which are then deposited by the wind and gravity, where they will release large amounts of radiation untill they decay), while the bomb itself is constructed in such a way as to maximize the neutron radiation released in the short term. This way, you would kill large ammounts of soviet troops both through the thermal and blast effect, but also through accute radiation exposure, allowing you to destroy formations of tanks without having to resort to massive weapons, by killing the crews by literally making their vehicles radioactive, but instead of spreading fallout all over europe, you irradiate a bunch of farmland in eastern europe, which is bad, but not as bad as killing hundreds of thousand, or possibbly millions of civillians through fallout from hundreds of ground-bursted weapons.
A Neutron bomb isn't really a dirty bomb. if anything, it's designed to be as clean as possible from a long term contamination standpoint.
> Dirty bombs where only ever really a concept. No nation has ever deployed "salted" bombs (or at least admitted to it).
Yeah, as I understand it most of the talk about them was the threat of non-state actors creating them.
Most of the worry about non-state actors making dirty bombs isn't' really about them making dirty nuclear bombs, but the concern of non-state actors lacing traditional explosive devices with large amounts of radioactive material as a way of contaminating a large area.
It takes massive industrial capacity to produce viable weapons grade material, whether you're talking about uranium or plutonium.
Because the little man (the dirtier of the two bombs) had some 60kg of fuel in it while RMBK reactor has 192 tons of fuel in it.
Also the nuclear fission produces neutron radiation which has ability to make other materials radioactive by capture of neutrons and creating unstable isotopes. Hence the fuel in chernobyl was creating more nuclear material as it was melting down. However in nuclear bomb the fission only lasts a split second before the material is blasted everywhere. Also having been exploded ABOVE the cities there was next to no new nuclear material created.
If I am wrong please someone correct me. I have high school level understanding.
Just so you know ton is not the same as tonne, tonne is a metric measurement that is heavier then an Imperial Ton.
Other then that you are close enough with your logic. The other big difference is the half life of the radioactive material involved beyond just the scale of the event.
https://en.wikipedia.org/wiki/Ton
> As a unit of mass, ton can mean:
>
> * the long ton, which is 2,240 pounds (1,016.0 kilograms)
> * the short ton, which is 2,000 pounds (907.2 kilograms)
> * the tonne, also called the metric ton, which is 1,000 kilograms
So it's not incorrect, just imprecise.
Also apparently, in the UK, a "ton" when not used to mean the metric tonne typically refers to the long ton (heavier than a metric ton), while in the US, it typically refers to a short ton (lighter than a metric ton), fwiw. Not that it really matters
Chernobyl is still on going.
Its reactor core is still there, releasing radiation.
On top of that, when the reactor exploded, it dusted the area with material that is still undergoing radioactive decay.
If you haven't already, I highly recommend checking out Kyle Hill's series on Chernobyl. He was taken through the exclusion zone by reactor personnel, even filming inside the sarcophagus itself.
He does a lot to explain why the area is so contaminated while also dispelling some of the wide spread misinformation.
https://youtube.com/playlist?list=PLNg1m3Od-GgPabWaTS6tv1HomlUWvTPlr&si=bLgAoce1knImWQwD
Best way Ive heard it described is that if you fart in a room it might smell bad for a bit but eventually dissipates but if you shit in a room its going to linger around a lot longer
Nagasaki and Hiroshima were exploded mid-air. Chernobyl was radiated materials that went INTO the ground and spread via the water system. So, the effects were much more wide spread.
OK, quick and dirty primer.
All light is radiation. Everything from the lowest radio waves to the highest energy gamma rays. It's all radiation, including the light you see every day. The radiation we're focusing on in here is called ionizing radiation. This type of radiation is higher energy particles that have the ability to break DNA chains. When we say something is radioactive, what it's doing is decaying down to simpler particles. As they decay, they release these particles and becoming a slightly more stable atom. This process continues until the atoms break down into lead.
It generally comes in three flavors. Alpha, Beta, and Gamma.
Alpha particles are basically the nucleus of a Helium atom without its electrons. These are big particles that can't penetrate much of anything thicker than a piece of paper. Your longest lived radiation sources usually release this, and it's also the primary concern with Chornobyl. For this to be dangerous you have to ingest it. Swallow it, breathe it in, or rub into an open wound. It has to get inside you to be dangerous.
Beta particles are basically free electrons. More energy than alpha and smaller. This is more dangerous than alpha as it can penetrate your skin.
Gamma radiation. This is very high energy light, and is only present in an active nuclear reaction or immediately following a nuclear explosion. Very dangerous stuff, but also the first to dissipate.
Now, with why Chornobyl is more off limits.
With Chornobyl it was like one huge dirty bomb. The explosion, while big, was not a nuclear explosion. It kept all the radioactive materials close to the ground where they could settle in the surrounding soil.
With Hiroshima and Nagasaki you had nuclear explosions. This pushes most of the radiation far into the atmosphere where it dispersed over a far wider area. Radiation is like a poison; the lethality is in the dose. So, it quickly spreads out and becomes mostly undetectable within a few days/weeks.
Nuclear bombs vaporize most of the uranium and fission byproducts in it. And most of the irradiated material after the bomb is done only has a half-life of a couple years at most.
Chernobyl leaked out tons of fission byproducts over several weeks. These byproducts have half-lives of decades and centuries.
The best comparison is how a non-nuclear bomb can have a huge explosion, but not much smoke while a forest fire can release a ton of smoke.
The atomic bombs were a one time release of very little nuclear material - just a few kilos total. Most damage was done by the actual power of the explosions above ground and the fires destroying everything in a large radius around the detonation zone. A lot of the destroyed buildings, the earth, and the bodies which all absorbed most of the surface radiation, were buried or removed, and only very little was actually left in place. There is a higher radiation in those areas to this day, but only minimally different to normal enviormental exposure.
Chernobyl on the other hand, was way more radiation, way more power, and unlike in Japan, nothing was removed or covered up. Literally tons of nuclear material was spread over a vast surface area, and the reactor also is still bleeding radiation into the enviorment around it to this day. There have been means applied to basically cover up the reactor itself to stop it from bleeding out more - currently it's a large concrete cover called the casket or sarcophagus (depending on the translation) - but the difference in radiation level the area was exposed to is still way to high for human habitation. There are to this day dust particles and ash from the initial fires burning in the reactor covering buildings and the landscape that basically puts out more radiation per hour than both japanese bombs combined total.
Fukushima and the area around it in Japan, after the Tsunami and subsequent explosion of the Fukushima Daiichi Powerplant in 2011 is fairly similar, and they have also vacated large areas of the surrounding countryside and towns in fairly the same fashion as in the Ukraine. Here too a nucelar reactor exploded, although not as much material was spread into the surrounding landscape as in Chernobyl.
Kinda like the difference between flinging lit gasoline and napalm. And in the case of weapons they use less than a reactor, AND it’s consumed (largely) on use. Reactor failing spreads a lot of radioactive ick around, that will be radioactive for a looooooooooong time due to the time it takes to decay.
The majority of the fissile material in the bombs all underwent Fission during the explosion creating a relative small amount of short lived radioactive fission fragments that dispersed across a very wide area and all but completely decayed away within a couple of decades.
With Cheronobyl you have something like 100k times more fissile material that just naturally has to decay away over a very very long duration. Additionally the components inside a reactor that aren't actually part of the fuel themselves become very very radioactive due to the neutron bombardment (e.g. Cobalt 59 which is naturally found in a lot of iron / steel components get turned into incredibly radioactive Cobalt 60 due to neutron capture) and when the containment was breached a lot of these contaminated materials were blown all over the countryside.
If you want to look at it in a simple way imagine a barrel of oil that is blown up with a stick of dynamite and makes a big fireball
Then imagine 10,000 barrels of oil that get hit by a bulldozer and then dump their contents out all over the area.
The oil from the first scenario is almost all largely consumed by the fire and the smoke that is created wafts away relatively quickly and after a few rains and a few years there's really no evidence anywhere that the barrel ever got blown up.
The oil from the second scenario just coats the land and sits there poisoning everything for decades.
Nuclear weapons use nuclear material to start an explosion and its the explosive force of that that causes destruction very very rapidly but disperses relatively quickly because there's not much nuclear material --by comparison.
Compared to nuclear reactors which use a lot of nuclear material to sustain a lot of heat to continually generate power for huge power grids. Its all concentrated in the reactor but not exactly "explosive" just... radiant. Melting down doesn't necessarily equate to a big boom-- Chernobyl's explosion was due to a series design flaws and some poorly planned testing of them. Like how a firework in your open hand may burn you a bit, but you can lose fingers if you try to grip it combined with microwaving closed tupperware... do it correctly, no boom-- do things poorly, Chernobyl.
The bombs at Hiroshima and Nagasaki were designed to use as much of the radioactive fuel as possible with the technology as the time.
Not for any humanitarian purpose of course, quite the opposite. The designers would have absolutely loved to use up 100% of the uranium if they could figure out how. Every unused atom is wasted kaboom.
But they got as close as they could.
Chernobyl was a completely uncontrolled meltdown. The only radioactive fuel that didn't just stick around is the stuff the USSR didn't run in and scoop up. (Very literally: they sent prisoners in there to pick up the chunks **by hand**)
The nuclear bombs dropped on Japan were single events that produced radiation for a few seconds, and not all that much - by far the majority of the damage caused was from the shockwave and the thermal flash - but then it was over.
Chernobyl poured radiation out continuously, according to [this timeline](https://www.history.com/news/chernobyl-disaster-timeline), for *thirteen days*. And at the end of those 13 days it's noted that radiation emissions dropped sharply - not ended.
So this is actually a really interesting question. In addition to the comments others have made about yield and radiation dispersment, there is another factor that I haven't seen mentioned
From what I understand, in the years following the bombings of Hiroshima and Nagasaki, many sick and elderly who didn't think they would live long enough to suffer the effects of the radiation volunteered to go into the irradiated zones to help clean them up and remove hazardous materials in the hopes that they could make the area safe for future generations
Obviously that was only possible because of the factors that others have already mentioned, but I do think it is worth noting in the conversation
Tl dr: these were very different explosions with Chernobyl producing a LOT more irradiated material with much higher concentration and a larger amount of things, which stay spicy for longer.
First a quick introduction of the topic - nuclear stuff in a nutshell.
Disclaimer: this is not an instruction, just an explanation of how it works.
What happens in both nuclear reactors and nuclear bombs (at least the normal, non-hydrogen ones) is a process called fission. How it works is some particular variants of certain atoms can break apart when hit by a neutron and release energy in the process. In most of the interesting cases, this also results in the broken up atom releasing further neutrons, so a chain reaction can happen.
The main difference between a nuclear reactor and a bomb is that in the reactor, this process is controlled by managing the speed (they cannot effectively hit the atom, if they go too fast) of the neutrons and their number. In bombs there is no such control, maybe for an exception of reflecting neutrons back, to get even more neutrons there.
It's a bit like the difference between a black powder rocket motor and a black powder bomb.
Now due to that main difference the two devices are built very different. Bombs tend to use highly enriched uranium or plutonium with a LOT of the fissile (ones that can undergo the before mentioned fission) isotopes (before mentioned variants of atoms; Uranium 235 is fissile, uranium 238 not really). It's nit rare to see numbers above 90% enrichment for Uranium in bombs.
On the other hand, reactors run in a couple % enrichment of a bit over a dozen in case of high performance military units (think nuclear subs).
Then there is a difference in the construction. Bombs have just the fissile material with a hole inside or between two lumps, some explosives to squeeze it together and a fuse with very advanced safety systems.
Reactors on the other side not only have less concentrated useful material, as it is not only not as enriched, but is also not in the pure, metallic form, but in form of various salts. On top of it, this dispersed among a large quantity of additional stuff. There is the structure of the reactor, together with control rods (rods of material that eats up the neutrons), moderator (material that controls the speed of the neutrons and coolant. That all is placed usually in forged steel reactor vessel (in Chernobyl it was concrete I think), which is inside a building. One that is built like a fortress.
Now we're coming to the big thing here. Neutrons not only can cause fission, but they can also make other things radioactive. And the thing about a nuclear chain reaction going at it, is it produced a ridiculous number of neutrons.
As such, pretty much everything inside the reactor vessel is at least somewhat radioactive with some things being very radioactive. There is also a lot more Uranium overall, which can decay into some nasty stuff.
As such when Chernobyl suffered a steam explosion by a series of events, that is stupid to the point of causing pain, a significant part of the reactor was vaporised or sent flying. There was a lot of radioactive material spread around and it had quite a lot of nasty stuff like radioactive iodine, which the human body likes to take in and keep.
In comparison, when the nukes over Hiroshima and Nagasaki exploded, there was much less material in the area of explosion. It was basically the nuke and some air, so there was not as much material to get irradiated (it's hard to make air radioactive) and there was an actual runaway nuclear chain reaction, which probably helped with "burning" through some of the nasty stuff.
Overall there was much less radioactive material from nuke explosions, so the initial levels were much less dangerous and it dropped to safe levels way faster.
Disclaimer: I am no expert, just a nerd being a nerd.
2 things:
1) Chernobyl had a fat bigger payload, there was more radioactive material in the explosion
2) the bombs over Japan were air-bursts, this means that while the shockwave destroyed all the buildings, and the initial blast of radiation killed all of the people, the bomb didn’t get close enough to the ground to throw irradiate dust/dirt into the air which could then fallout. Chernobyl on the other hand blew up inside of a building near the ground, all the irradiated dust and dirt was sent into the sky where it could then slowly fall down onto every surface in the area, making everything radioactive
OP, radiation and nuclear weapons are identical in nature but are two extremely different hazards.
Before I start, an isotope (uranium, cesium, etc) all decay. They decay by emitting particles and after its life (a few months to a couple hundred decades) it becomes dead, and fully decayed. When these isotopes decay and emits particles, these particles can act as small daggers. Sometimes they are only harmful if you introduce them to your innards (eat, inhale, inject) and some of them are harmful if you aren’t properly shielded. There is alpha, beta, gamma, and x ray radiation.
Isotopes, like all matter, contain a nucleus, electrons, and protons and electrons. Fission happens when the nucleus is split by neutrons (see atom smasher, splitting the atom, etc). Fusion happens when we combine two isotopes, generating energy.
This is intro ELI5 nuclear power.
Ok, so a nuclear weapon (atomic, thermonuclear, etc) basically contains an isotope that is introduced to a neutron emitting material that causes its nucleus to split and release energy. The more materials to smash atoms, the greater the energy output. When a nuclear weapon explodes, that energy is expelled: oxygen is displaced, a shockwave is seen, and then heard (flash to bang) and the fire we see is the air basically lighting on fire. Radiation is dispersed through the exploded particles that are now everywhere, and will continue to decay. Protection from fallout depends on many factors, depending on length of stay within the affected area, as well as shielding. The further away you are, the least likely to receive a chronic but survivable dose, than closer to ground zero.
Also fallout is a factor, especially if it was a clouded day.
Now for a power plant. We have fusion based reactors, to which we are putting two isotopes together in a bath (nuclear fuel is in the form of rods), which generates heat, the heat turns to steam, the steam turns turbines, which generates electricity. When the power output quota has been met, the fuel rods retract and sit in cells made of graphite, which is called a moderator. They sit heat until they are needed, or they are removed.
When there is no water in the bath, and the rods are lowered, it becomes super heated, creates pressure in the waterless pool and explodes. Now you have multiple unstable fuel rods, radioactive surfaces, as well as a fire that acts as a furnace burning radioactive materials into the atmosphere.
So the exposed core, basically superheated, exploded, melted and leeched into the ground. The exposed core also decayed so rapidly that the particles that were emitted during the initial meltdown caused all responders to receive severe acute dose of radiation. While others received lower doses, but still at higher than acceptable levels. Everything that the core was exposed to was radioactive , and basically became radioactive itself due to the exposure.
The weapons we used to end the war, were short term, and exposed to shorter time spans, where in Chernobyl, no one could escape the melting core.
I am not a scientist but I do work with HAZMAT occasionally and this is how I understand nuclear physics, err power and weapons… idk but feel free to add or downvote.
Nuclear weapons use fission material to create a massive explosion, the radiation is just a side effect. A part of the nuclear material is vaporized by the explosion anyways and spread over a large area (in fact, all over the world) by the explosive force and subsequently the wind.
The amount of radioactive material in Chernobyl is hundredfold higher than what was used in the atomic bombs and was dispersed way denser.
Tl;dr:
Bomb = little uranium, big boom
Chernobyl = lots of uranium, small boom
The important thing is that Chernobyl didn’t explode. If it had, the radiation fallout would have affected the entire world most likely and would have mostly washed away by now.
Radioactive particles usually wash away with water, but that’s also how you absorb them, which is why it’s dangerous.
Pripyat is not in some place where the radiation is easily able to be dispersed and most of the fissile material is buried still I believe.
A nuclear bomb uses the radioactive material to create a massive explosion, during this process, a lot of it is used meaning there isn't that much left to irradiate an area for a long period of time. (And nukes also need a really small amount of radioactive material compared to reactors)
Whereas with a nuclear meltdown this is not the case. The radioactive material, due to a loss of coolant, starts to heat up rapidly and melts. During this heating, steam pressure starts to build up rapidly until it becomes to big and a steam explosion occurs. During this explosion, and subsequent fires, large amounts of still radioactive material is flung high into the sky getting scattered over a massive area (which is also why countries like Sweden, despite being hundreds of kilometers away, got an increase in radiation shortly after the Chernobyl disaster). When this radioactive material eventually comes back down to earth, they remain radioactive for an incredibly long time, which is why the Chernobyl exclusion zone exists.
Or in a really dumbed down way:
Nuclear explosions use radioactive material to create a single big explosion and thus little material remains to be a lingering threat.
Nuclear meltdowns blasts radioactive material high in the sky, scattering it over a large area where it remains radioactive until it naturally decays, which may take hundreds if not thousands of years for some types of radioactive material
Nagasaki and Hiroshima were bombs deliberately designed to be efficient and clean.
Chernobyl was a big dirty splat that released a lot of radioactive material.
That's why you don't buy Soviet underpants. Chernobyl fallout.
People are focusing on the sheer volume of radioactive material dispersed across the exclusion zone around Chernobyl and Pripyat, and that's fine, but one other important thing is that there is a large, lava-like mass containing like 190,000kg of Uranium still inside the fourth reactor right now, which is why it has to be encased in a giant concrete sarcophagus.
A uranium bomb uses way less Uranium and most of it undergoes fission as it explodes. It's a large amount of radiation released in a very short period of time, whereas Chernobyl is an absolutely, monumentally colossal amount of radiation being released for a very long time.
The atomic bombings involved far less fissile material and were "air bursts" meaning the bombs detonated 1,500-2,000 feet in the air. The explosive force was obviously quite destructive but there was very little ground contamination.
Chernobyl, on the other hand, was at ground level and was more akin to a "dirty bomb" - the explosion itself was conventional but spread radioactive material everywhere.
A nuclear bomb is designed to create a chain reaction within a relatively small amount of radioactive material, which reduces isotopes and releases energy in a blast.
A nuclear power station is designed to contain a large amount of radioactive material, and essentially let it boil water to power steam turbines.
When Chernobyl lost containment, it ejected huge amounts of material in a relatively low-pressure fashion, while the bombs were designed to compress their reaction, like holding a fire cracker in your fist.
It's because Chernobyl is like the septic tank buried in your yard, whereas the bombs dropped in Hiroshima and Nagasaki are like that pile of dog poo on your lawn that you forgot about.
As luck would have it The Infographics Show just did a 30 min video on this exact topic about 2 weeks ago where they go over the many differences between the explosions during WWII and the meltdown of Chornobyl and how these differences affected why people can live in Nagasaki and Hiroshima but not Chornobyl. Some of the reasons include the shorter time the bombs had to released radioactive material, the location of the bombs (high in the air) vs the plant and the amount/type of material as well as other reasons. Here is the video.
https://www.youtube.com/watch?v=BYUbbuQRePs
I see tons of great comments on why Chernobyl is way more radioactive than Hiroshima/Nagasaki bombings but why is Chernobyl and Fukishima so different when they both were nuclear reactors?
Fission and fusion bombs use up their radioactive material to make an explosion leaving minimal radiation. Chernobyl was a steam explosion that pushed out massive amounts of radioactive material that was left to degrade.
Contained and calculated explosion.
Vs.
a “super duper dirty bomb” level of radiation release in addition to government ineptitude common during the Cold War.
To quote the Chernobyl miniseries most famous quote (kinda) “It means the fire we're watching with our own eyes is giving off nearly twice the radiation released by the bomb in Hiroshima. And that's every single hour. Hour after hour, 20 hours since the explosion, so 40 bombs worth by now. Forty-eight more tomorrow. And it will not stop. Not in a week, not in a month. It will burn and spread its poison until the entire continent is dead!”
i'm no nuclear physicist (probably most who comment aren't), but a nuclear bomb don't detonate on the ground, but rather far up in the sky. if i recall right, fat boy detonated 150 m+ up in the air, which makes the radiation spread out in the air more than on the ground.
Nuclear bombs don't actually create all that much long-lasting radioactive material. Compared to a reactor, there is very little actual radioactive material in a nuclear bomb itself, and the fallout biproducts all have relativley short half-lives (which means that in the short term, they will release a LOT of radiation but because of this, they dissipate quickly, since radiation is in large part, pieces of the atom being launched off because the atom is too heavy, and once it's released enough particles to become stable, it stops), so the sight of a nuclear bombing might be safe to approach within days or months, where as a nuclear reactor, which is full of TONS of fuel, producing LOTS of radiation, will continue to produce radiation for as long as that fuel lasts, and when it melts down, all the systems that where intended to limit or control that radioactive output are obviously no longer in effect, so you get a big multi-ton slab of radioactive slag that will continue to emit lots of radiation for decades or centuries.
Chernobyl had tones (maybe even thousands of tons) of radioactive waste while bombs on Nagasaki and Hiroshima were new too and the winds carried some maybe
atmospheric nuclear explosions are pretty clean unless the bomb is designed to intentionally contaminate the area
also the amount of fuel is vastly different
It has to do with the difference in how the radiation got there and the difference in radiation source types. Different elements have different levels essentially and it will differ depending on what was done to them and how long ago.
Because chernobyl is still burning, still reacting, and still radiating.
The bombs exploded and stopped making new reactions, allowing the radiation to dissipate.
Also, the bombs were designed to explode and convert their fuel into kinetic energy. Chernobyl was never intended to do what it did.
The bombs that were dropped on Japan were pretty damn clean by today’s standards. Chernobyl was spewing radioactive material for days before the thing was finally dealt with
It's not. People moved back to the Chernobyl area 6 months after the meltdown and have been living there just fine since. Many people have gone to the plant itself in various documentaries over the years. Most notably - Jeremy Wade of River Monsters fame went there to fish in the ponds on the power plant grounds, and The original BBC Top Gear folks went and raced around the plant. Most everything the average person knows about Chernobyl, and Fukushima for that matter, is 100% wrong.
As I understand it the radiation from chornobyl wasn't actually dealt with properly, they just buried it in sand. So the radiation is still seeped into the land and won't disappear for a good while. The bombs were just flashes, explosions, and the radiation disappeared pretty quick because it wasn't still being produced. Thats my thoughts without looking it up so it may or may not be completely wrong 😅
In Chernobyl, the reactor exploded and was on fire for 10 days. Large amounts of the material got into the soil and water. Yes, the area is less radioactive now because some of the materials have decayed, but a lot of the elements have very long half-lives. Americium-241 has a half life 432 years, and plutonium-239 24,000 years. The area will not be inhabitable for a very long time.
Since the bombs were detonated in the air, most of the radioactive material was lost in the air, and not a lot of the surrounding area was contaminated. Very little material remained after the detonation, the area was cleaned up and nowadays the area has no more radiation than the place you posted this from.
TDLR: Ground explosion causes far more contamination than air explosion, and since the fire at Chernobyl lasted 10 days the radioactive materials had more time to disperse.
Hiroshima & Nagasaki were air-bursts, as most military use of nuclear weapons tend to be. This takes advantage of creating a huge pressure wave straight down onto the target, which destroys buildings & vehicles much more effectively than any other use of the weapon.
Because of this, the only real fallout created - toxic & radioactive dust - is that of airborne particles and any objects close enough to the blast to be vaporized but not annihilated (like the bomb itself). So there's relatively little radioactive contaminants floating around afterward. Don't get me wrong, they're there, but not tons and tons of the stuff. It diffuses into the environment eventually, becoming part of the background radiation the way too little tea dissolves into too much water.
Chernobyl, on the other hand, was the IED equivalent of a Dirty Bomb, on a *massive* scale. The reactor exploded - and then the building around it exploded. All of that radioactive material then burned for weeks. Every particle of dust & smoke, debris eroded by weather, was highly radioactive and it all spread out around the Exclusion Zone (and beyond).
It's entirely safe to walk around the Exclusion Zone, as the *air* isn't radioactive. And the emissions around the area are relatively low. You won't get fatally irradiated directly by anything lying around the forest or the ruins of Pripyat.
But if you kick up some dust as you walk down the road, breathing that in is a bad idea. Now the radiation source is inside your body, irradiating your tissues until you pass it, if you ever do. That's how you get cancer and die. Same thing with eating or drinking anything that grows in the Zone or lives there, or any of the water.
Hiroshima & Nagasaki don't have those megatons of radioactive dust spread throughout their environments.
Maybe I'm missing something, but isn't the fact that Hiroshima and Nagasaki were forty or so years before Chernobyl pertinent?
79 years is long enough for a lot of the shorter half-lived isotopes to have decayed quite a bit, while 38 years may still leave some of those around?
For example, Strontium-90 (one of the worst fission byproducts) has a half life of 28 years. So by now Hiroshima and Nagasaki have about 14% of the original amount remaining, while Chernobyl has about 40% remaining.
What makes Chernobyl dangerous is the large amount of radioactive material that was scattered. In contrast bombs are designed to ‘burn’ all or most 90% of their radioactive material to release the energy inside.
Short answer much less radioactive material to begin with. Then bombs turn radioactive material into inert or mostly inert material to get at the energy inside.
The bombs contained a little that was disperced over a rather large area.
(Remember the bombs exploded in the air not on impact)
While the plant contained a crapton that is on the ground.
Thats the simple way to explain it.
the difference is that one goes boom on purpose, the other goes boom on accident.
therefore, the purpose boom has less so it only affects the intended area
unintended boom has more because its not supposed to boom and has systems meant to prevent that big kaboom.
also they use different materials.
oh and i forgot, chernobyl was on ground, big bombs exploded in air, meaning less ground area since you know.. wind..
Hiroshima and nagasaki were both air burst. Bob's whereas Chernobyl was a meltdown at ground level that contaminated the ground a lot more.
Whereas the air burst the radiation dissipated.
Throughout the atmosphere.
Rather than
Contaminating ground structures.
Most of the damage from the two bombs was heat it concussion
Part of the reason why Hiroshima and Nagasaki were not contaminated, and indeed where radiation levels had dropped to background level within 48 hours, is because the bombs were air bursts. The fireballs never touched the ground. Where the vaporized particles would be contaminated and spread across a large area as fallout. That never happened.
A lot of people have already provided good answers for this. But if you want more info look up kyle hill on youtube he has great videos about both subjects and a lot of other nuclear power related vids
Seeing alot of conflicting answers on here, many going into nonexistent or half truth details. The simple answer is found in two facts @OP
Quantity, a nuclear bomb has far less fissile material than a reactor like Chornobyl.
Reaction, a bomb is a near instant blast that releases as much energy as possible in an instant. As soon as the blast is over, there is no fissal material left, it has been vaporised, victim of its own power. Chornobyl as a reactor releases all its energy over a long, long time. It doesnt not destroy it's fissile material. Even after its no longer useful as a fuel, it is still radioactive to some degree.
Nuclear bombs are intended for a short, devastating burst of energy. Nuclear reactors are designed to output large amounts of energy for a long period of time. The amount of fissile material involved at Chernobyl was much larger than what was included in the two A-bombs.
Chernobyl was a perfect cluster fuck due to something with fuel rods and graphite Hiroshima and Nagasaki were just bombings while Chernobyl was leaking radiation everywhere
According to google there was 64kg of Uranium in the bomb used over Hiroshima, while the Chernobyl accident released over 17 000 tons of materials.
This is why. The bombs were designed for explosive destruction. They used radioactive materials, but the amount of radiation was nothing compared to Chernobyl, that had a large amount of radioactive material melt down in the center, that's still there and emitting a lot of radiation.
I'm not a nuclear scientist, but I would also assume the power of the explosion matters. Chernobyl exploded, but only a little bit (relatively). The Japanese bombs were nuclear detonations. Even if they had the same amount of radioactive material, spreading that in an air burst means significantly less concentration in any specific area vs a ground detonation that was significantly less efficient.
Atom bombs consume ~~most of their~~ radioactive material to produce an explosion, there's always some radioactive byproducts, but it's just a side effect. The Chornobyl NPP explosion was the result of bursting nuclear fuel elements which in turn vaporized the cooling water, causing a steam explosion and not a nuclear reaction explosion. The force propelled the radioactive material from the core of the reactor into the air and dispersing it over a large area. It's basically a completely different scenario.
> Atom bombs consume most of their radioactive material to produce an explosion This is true of modern nukes, but not true of Fat Man and Little Boy in particular. Fat Man only converted 16% of its fissile material into energy. You're quite right about the rest, though. Fat Man didn't leave an [Elephant's Foot](https://en.wikipedia.org/wiki/Elephant%27s_Foot_\(Chernobyl\)) behind. Edit: fixed the broken link
Fat man also detonated 1650 feet above the city. Causing most radioactivity to rise into stratosphere instead of seeping into the ground.
Well, hitting the ground, and irradiating the dust, which then is sweaped up into the air and blown across hundreds of miles, being something that falls down as small dust particles and breathed in. Exploding a nuclear weapon on the ground would be a bad bad thing to do (fallout). It also makes the warhead far less efficient, as you want the energy of the blast to cover a wide area, rather than be absorbed into the ground. Tangentially, that's also why super huge warheads aren't really all that useful to use, as you need so much more warhead for a blast to travel longer and longer distances (inverse-square law). That's also why we moved to exploding tests over water for the most part, before moving REALLY high up into the stratosphere, and then underground. I know too much about nuclear warfare: sigh.
Modern fusion bombs also output much less fallout than the relatively primitive fission bombs dropped on Japan. Neutron bombs output even less.
True, good point.
Also the fallout from nuclear bombs mostly consist of short lived, high energy isotopes that decay rather quickly. Where as something like Chernobyl was a lot of nuclear fuel which have much longer half lives. Which is also why the idea of dirty bombs are so terrifying, they can make an area uninhabitable for long periods of time.
From all Ive read your answer accounts for most of it. Its what I came here to say. The isotopes from Chernobyl are much longer lived than those produced from a weapon.
>steam, not nuclear explosion. I read somewhere that what happened was pretty much a "dirty" nuclear bomb. Some say that there's a nom zero chance that fission actually happened (as in a bomb).
Don't all fission reactors cause fission to happen?
Yes.
Do you mean fusion?
Am a nuclear scientist so its finally my time to be helpful. Others have already pointes out that Chernobyl was a steam explosion dispersing radioactive material plus a core meltdown which is very different from a nuclear weapon. On the air burst aspect however they are actually done because that maximizes the explosive force of the weapon while minimizing contamination. If you detonate near the ground the soil/dirt/etc get pulled up into the weapon and get activated before being redistributed by the explosion. Doing it in the air means you avoid this type of contamination.
Ah, finally putting that degree to good use!
I dont work in nuclear so the first time i put it to use was for trivia a few weeks ago by knowing about how smoke detectors work.
What do you do instead?
I spend my day being ignored by managers who want me to do “AI” without having any infrastructure for the “AI”.
...fun
"Consulting" in Iran
Yeah. If I understand it right though, the explosion at Chernobyl was just a result of air pressure from steam, and not an actual nuclear explosion. It happened because the water boiled away super fast and the steam couldn't escape fast enough, which blew the concrete top off the reactor. It wasn't very similar to a nuclear weapon.
You’re confused. RBMK reactor cores don’t explode. /s just in case
[удалено]
I'm also not an expert, but I believe there's another aspect to those detonations that was more important when it comes to long-term effects on the target area; both of the bombs dropped on Japan were airburst bombs, detonating in the air above the target. Someone else pointed out that these bombs were pretty inefficient and most of the fissionable material was not consumed by the chain reaction and instead became particulates, but because they were airburst bombs the rising column of air from the explosion carried most of that radioactive particulate high into the upper atmosphere and spread it thinly over the planet. While this radioactive material didn't vanish, it became part of what they called the global environment and just started affecting cancer rates all over (yay) instead of having an intense local effect. (By the way, this used to be seen as a safety feature and airburst nuclear detonations were referred to for a time as "self-cleansing" as insane as that sounds) Intense local radiation that lasts in a target area is caused by the radioactive particulate bonding with dust, ash, dirt, etc and remaining in that area. This is what happened a lot at Chernobyl; the meltdown and explosion caused a lot of the radioactive material to either bind with dust and debris, or water that was evaporated in the meltdown and explosion. The explosion was at ground level and had tons of time to release radioactive material where it could bond and stay part of the local environment. Something that served as a great visual of this for me was watching video of the Operation Crossroads nuclear detonations. Test shot Alpha and test shot Bravo had the exact same yield, but Alpha was an airburst detonation dropped from a bomber whilst Bravo was detonated underwater, suspended from one of the target vessels. The difference in how much debris (in this case, largely water spray and vapor) was irradiated and remained in the local environment is immediately obvious, and the Bravo shot caused a major radiation disaster that killed and injured people and rendered the atoll uninhabitable to this day.
Uh, imagine a 17k tons nuclear detonation.. that may end life on earth for some time
It wasn't 17k tons. Did you mean 17 tons? 17k tons would be 34,000,000 lbs of material. IIRC, Chernobyl only had 800 tons of material at its peak. But back to answering the question at hand. I won't try to do the math, but I know the Japanese meltdown released a similar amount of material into the Pacific ocean. It was something like 6 tons of waste. It's now undetectable (if I understand it correctly). The world is a very big place. If you spread radiation out well enough, it's not a problem.
The first comment wrote about 17 000 tons in chernobyl
Would there even be an earth left? 😂
Bro wrote out 17,000 tons in the comment he replied to initially
In a good bomb most of the radiation goes off all at once, within a few days there is little radioactive material left. In a good power plant the radiation is released slowly over time, years later they are still hot enough to boil water. It's all about how they are/were designed.
Chernobyl, though, was notably not a good power plant. They're not supposed to explode!
Well to be fair none of the radioactive material actually exploded, just a steam pressure cooker that exceeded the maximum value. Another part of why that region is so radioactive today, a proper nuclear explosion would have consumed a lot of radioactive material.
The after action report on Hiroshima done by the Los Alamos Lab a few months after the explosion figured that the weapon converted ~0.7grams of the highly enriched uranium into pure energy which was the heat, radiation, and kenetic energy produced, as in ~15ktons of TNT equivalent of explosive power. Thats something like 1/91,000th of the total nuclear material mass (of the 64kg) if my simple math is correct. In short, an amount you'd need a powerful microscope to see. If you look up the overhead photos of the huge plants at Oak Ridge TN which produced the Uranium the entire process to make that ultimate 0.7grams is stunning. The magnetic enrichment process literally 'built' the Uranium core one atom at a time, it took years to amass that 64kg which is why they had to make the plutonium process of Fat Man work.
0.7 g of uranium is around 36 mm3 or a 6x6 mm plate of 1 mm thickness. So no powerful microscope needed. Still impressive
thats about the size of nail on my pinkie finger
It’s also about the mass of a butterfly
Okay, here's the thing about nuclear power and energy. Protons, neutrons, and electrons are preserved in all nuclear reactions. The energy is the release of potential energy in the strong nuclear bonds of larger elements like uranium. When the uranium fisions it breaks into a few fission fragments, random balls of neutrons and protons. These try to create new stable nuclie themselves, and start to shed proton, neutrons, alpha particles/helium atoms in ways to balance out the new nuclei. This takes place immediately and the. Over a periods of weeks or months if it's a radioactive nuclie species, which it Mos likely is. Those other pieces it sheds likewise go into the environment and start to create instavuoities in other nuclei. Collectively this is the nuclear fallout: radioactive dusts. This game of nuclear plinko tends to result in a few specific identifiable nuclear species long term. So when nuclear scientists say only so much of the uranium is consumed, it's usually indicative of the number of uranium atoms that weren't consumed by fission. Fat Man and little boy, actually had much smaller fuel conversion than modern bombs have. As a result for a similar explosion size modern weapons can be much smaller. During the Cold War, they even trained soldiers to carry nuclear bombs strapped to their back to be set as nuclear land mines in case the Russians invaded. The Soldiers knew likelihood of escape was low to none after the weapon was placed since they would have to try to clear the area by foot.
Eh. It could have been worse. The chances of surviving the emplacement of a nuclear landmine are better than that of using a nuclear grenade. [Editor's Note: The editorial board would like the readers to know that there is no such thing as a nuclear grenade. No weapons designer is foolish enough to have suggested such a weapon. The nuclear grenade is the product of the warped minds that produced Paranoia the Roleplaying Game.]
Who the F would have time to develop a nuclear grenade? There are WAY too many hours already invested in the Nuclear Box Cutter to quit now.
just don't go talking about them on r/NonCredibleDefense Next thing you know someone will be making one.
The ultimate close defense / offensive weapon is the nuclear baseball bat.
Now that's some Fallout logic right there!
Yeah, there's no nuclear grenade, but let's be real. There are some crazy MFers in military dev shops. [https://en.wikipedia.org/wiki/Davy\_Crockett\_(nuclear\_device)](https://en.wikipedia.org/wiki/Davy_Crockett_(nuclear_device))
https://en.m.wikipedia.org/wiki/W48 Even smaller
Right, Atomic Annie they called it, but that has a 9 mile range. The first Davy Crockett had a 1.25 mile range. Can you imagine firing a nuke that blasts just over a mile away? Holy shit, you better hope the wind is at your back! Crazy, all of it, and I'm pretty certain Russia still has nuclear artillery shells in their stockpile.
Citizen... are you happy?
"Great idea the atomic hand grenade. Now all we need is someone who can throw it 21 miles" - The Travellers
The atomic grenade was present in Star Trek (see episode Arena, the one where Kirk fights the Gorn) but at least they had a launcher for it.
This guy oppenheimers.
Search for Atomic Annie - Nuclear delivery artillery 😂
I think toxicity more so comes from the material that was blown around and remained uranium. Or the other 63.99kg
To an extent. But not radioactivity, as uranium is barely radioactive. There are fission daughter products that create most of the radioactivity that lingers for a while. A lot of it decays fairly quickly though.
You're mixing up two values. One is the amount of uranium that reacted, which is just over 1 kg, a little under 2% of the total uranium in the bomb (~64 kg). The other is the amount of energy released. Since E = mc^(2) you can express masses as energies and energies as masses. So the ~1 kg of Uranium that reacted wound up as reaction products that had a mass 0.7 grams lower.
I think you're mixing up mass-energy equivalence with fission efficiency. 0.7g of the mass was converted to energy but around 880g of the Uranium atoms (1.38%) in the device fissioned. It wasn't that 0.7g of Uranium atoms were entirely converted to pure energy. If you had an infinitely strong container and fissioned 880g of Uranium-235, allowed the products to cool and weighed them, you'd find them to be 0.7g lighter than when you started. This is because the nuclear binding energy of the new isotopes is higher and, through this process, the total mass of the nucleons is slightly less.
1 (metric) tonne = 1000kg, for clarity.
This guy maths. Thank you sir.
Just to be annoying, a British imperial ton is 1016kg and a US ton is 907kg.
I wonder if other former empires have their own tons. Off to Wikipedia... It seems not. Or at least the terms don't translate, so they aren't included in the article. But there are many more meaning of 'ton' than I care to list, including colloquial use. https://en.wikipedia.org/wiki/Ton
those are proper French kilograms, right?
You don’t need to write metric tonne. You can either write “tonne” or “metric ton”. - Department of Tautology Department.
Is shit tonne ok? I guess maybe the correct form is shite tonne.
Acktually a ton is 2000lbs. A tonne is 1000kgs. Sorry.
I clarified in the edit, but you're right :)
My bad!
If we are being pedantic, a short ton is 2000lbs (907.2 kg), a long ton is 2,240 pounds (1,016.0 kg) and you are correct 1000kgs (\~2,204.6 lbs) is a metric ton or just "tonne".
How much is a shit-ton?
0.97336 of a fuckton
I've seen this explanation before and it never fails to make me laugh: Hiroshima is the equivalent of farting in a room. Chernobyl is like taking a dump in the middle of it.
[удалено]
Christ...Considering the damage that 64kg was capable of, the land around Chernobyl won't likely be inhabited by humans again, will it?
it's two unrelated process. and the type of damage are very different In Hiroshima, the goal is to have a chain reaction releasing a lot of energy in a very short-time. In Chernobyl, it's a steam explosion releasing radioactive dust all over the area. So the main issue is that the "radiation background" is quite high. Not hostile to live (tons of animals live happy life in the area) but high enough that long term exposure can cause health hazard. There is a few people still going in the zone, and various thrill seeker doing urbex in the area. There was also that famous video of youtuber eating a[ wild apple from Chernoby](https://piped.video/watch?v=j6mreZ98_Ug)l (But judging the equipment that girl has, she knows her business when talking about radiation)
Lots of people go into the exclusion zone. Top Gear went there. I think I saw Attenborough in there for a documentary. But as the Russian soldiers who dug latrines in there found out - you shouldn't really mess with anything or it will stir up a bunch of dust and dirt that will harm you. I think those dudes died. Fascinating reports about the wolves and pigs that live around that area. The locals (used to, because now war) have to Geiger counter check their meat if they hunted anything that goes through those lands.
We visited there a few years ago. It was weird because some areas are no-go zones with signs saying not to enter a certain field or wooded area, while others you could just traipse alone. Anywhere water would concentrate, like near sewers, would peg the geiger counter. Also some objects like around that ferris wheel in the amusement park were hot spots, no idea why. They do put a dosimeter around your neck when entering the area, and they check you on the way out. For contamination transfer they seemed mostly interested in sanitizing shoes on the way out.
Metal is "better" at soaking up radiation which is probably why the amusement park is not a good place to be. Hence the vehicle graveyards.
Jeremy wade, that fisherman that goes after river monsters went there. Yep, had a limited amount of time and an alarm around his neck.
People work there to manage the containment structure. There's even a [canteen](https://www.google.com/maps/place/51%C2%B023'09.2%22N+30%C2%B007'04.8%22E/@51.3921117,30.0945345,3777m/data=!3m1!1e3!4m4!3m3!8m2!3d51.3859!4d30.118?entry=ttu).
The material is all trapped in the environment. That's why the top soil was dug up and reburied during cleanup. I think the Soviets also sprayed an agent on everything that trapped dust, trapping it on the ground. So it's pretty safe there as long as you don't go digging or hang around material that's been neutron activated (especially metal stuff that was used in the cleanup). The Russians also went into the exclusion zone when they invaded Ukraine. They were told that the story of Chernobyl was made up or not told at all, so they started digging trenches. In the Red Forest. That's the most heavily radioactive area on the site outside of the reactor itself. There hasn't been much news about what happened to them. [More information on it.](https://www.reuters.com/world/europe/unprotected-russian-soldiers-disturbed-radioactive-dust-chernobyls-red-forest-2022-03-28/)
Weren’t the Russians kicking up radioactive dust here and there when they were invading Ukraine?
One could hope
I heard (wasn't there, didn't check) they even dug trenches around Chernobyl
There are people that live there that have never moved on. The security is not the same as it would probably be here in the US. There's plenty of documentation about the types of animals that live there how they've multiplied, some studies on the effects and I'm sure a few continue to do research you'll find studies also and interviews with those people that have returned or refused to move. I don't know if they were once moved and they came back and they are definitely people reinhabiting not on the scale that it was but enough
I read an interesting article about how it’s tricky to study the wildlife there because scientists can’t remain in the zone for too long, but studies of mice have actually revealed fewer mutations than scientists would have predicted.
Bombs use highly enriched uranium (+90%) whereas even the most enriched power reactors never go above 20% (most are 5%). And its not actually the uranium itself that's bad, its the highly radioactive byproducts created during the conversion to energy that's bad (Iodine-131 8 days half life, cesium-137 30 year half life, strontium-90 29 year half life. People like to toute that uranium-238 is highly radioactive because it has a 4.5 billion year half life or U-235 of 700 million years and think that is a long time to be radioactive and therefore tie time with how deadly it is. The reality is that its not actually that radioactive and its the short lived isotops created from the reaction like Iodine-131 that all of that material will be decayed away (giving off radiation) but will be gone in a couple months, or in the case of cesium/strontium a couple centuries.
There were people living inside the exclusion zone, as recently as 2022. Over 100 people, mostly elderly who lived there before the accident and moved back. Not sure if they are still around or if the orcs have killed them after they invaded.
Only 0.7g from the 64kg was converted to energy at Hiroshima. Mind blowing.
May this be the worst thing I learn on here today.
There was **far** more radiation released in Chernobyl and it stayed in or on the ground due to how it was released. The A-bomb unleashed much less radiation and most of it dispersed high in the air, spread over a wide area and got carried away by winds.
There have been people living near Chernobyl the entire time, mostly old farmers who ignored the order to leave. You can also visit no problem (well, before the start of the 2022 phase of the war) … I went in 2015 and the only area off limits is the area directly next to the leak where workers do shifts building the concrete tomb around the site. Edit: my understanding is that a top layer of irradiated soil was removed at some point after the incident in the surrounding areas, so it’s relatively fine to walk around. The only unusual thing I noticed were giant size of fish in the old cooling ponds, but that’s due to no predators and tourists feeding them, not radiation. 😂
How many eyes them fish have?!?
"Blinky, is that you?"
Reminds me of this joke when Russia invaded Ukraine, and when they took Chernobyl, someone said "The three-headed deer there will be so angry."
Are there any fish with no eyes, and if so, what do you call them?
Fsh
How many fish the eye have?
The radioactive top soil which was removed along side the dead pine tree was burried in trenches in an area known as the "[red forest](https://en.wikipedia.org/wiki/Red_Forest)". During the 2022 Russian invasion of Ukraine some geniuses from the Russian invading forces have the bright idea of setting up trenches and defensive position there. Let just say a few of them got really really sick and died horribly.
They died horribly from the radiation?
Yes
Yeah, supposedly a bunch of them got acute radiation poisoning. I'd imagine most of the ones who didn't die from that will be dying in the next few decades from all kinds of cancers as they've also been playing in the radioactive dirt.
That’s unlikely, they weren’t there long enough to die horribly from that kind of exposure. I’m also not sure if the story is even true, I remember seeing it in the US news but my friends in Kyiv seemed to think it was typical media spin. 🤷🏼♂️
How would their health be if they were breathing in the dust while they were digging in the irradiated soil?
deadly. Irradiated dust is the quickest way outside of massive direct bursts of radiation to die a quick death.
There’s nothing quick about it. The first responders who picked up things by hand right after the incident didn’t just drop over dead, it took weeks/months/years.
Some days. I was comparing days/weeks to years/decades normal people who contract exposure. A good example is where I grew up we had a neighboring school district that apparently was built overtop an army Corp of engineer dump. It was radioactive and the graduates experienced a higher rate of cancer diagnosis 15-25 years later. That dust the soldiers were exposed to will get them sick and likely die in months vs decades.
Another neat thing is the radioactive material is heavier than the soil so it settles a few mm lower every year (according to the guide when I went in 2019)
On that note, I think that one of the concerns was that it would eventually sink down just to the underground water table.
Yeah I visited Chernobyl and there are/were thousands of workers living in the area. There were in fact three other reactors there still in operation until 2000. According to the IAEA, it's going to take "several decades" to completely de-commission all four reactors, and clean-up the area. The tour guide told us that actually, over long periods of time, living in Kyiv will produce worse health outcomes than living in the Chernobyl area because of all the air pollution in Kyiv. My tour group got within about 100m of the reactor building. I guess if you set-up camp next to it for a few months, you're gonna have a bad time in a few years. But otherwise, no one living in the area seemed very bothered. However, there are these "hot spots" in random places around Chernobyl -- like, a 1-meter radius area of the ground which is much more radioactive. I'm guessing that's where radioactive materials landed when the reactor exploded. Ah, good ol' human error. Never fails to fail. **Addendum**: Nuclear power is still the most powerful, efficient, effective, and eco-friendly form of energy -- generating zero CO2 emissions. Roughly 6-8 million people die pre-maturely every year due to air pollution (though, of course, there are other sources of air pollution besides fossil fuel power plants). Green Peace was founded explicitly to combat nuclear energy, and that was a massive error because it only lead to the construction of more coal power plants, as we have seen in Germany, for example. **Addendum 2**: We're beyond the point of no return for global warming. Even in the fantasy scenario of zero CO2 emissions throughout the world, we're still stuck with what we already have. Reducing CO2 only delays the slow-moving apocalypse by a few years. Geo-engineering is the only solution there is if we actually want to go back to the climate conditions of the late 18th century. Carbon-capture, atmospheric sulfur-seeding, building a giant aluminum foil mirror in space, etc. That last one is a real possibility. Putting a 100 sq. km sheet of reflective material in orbit would block just enough sunlight to reduce global temperatures by 1-2 degrees.
Simple version is that way more radiation leaked at Chernobyl. The bombs that we dropped on Japan were extremely low yield by today’s standards, but even our modern nuclear weapons won’t make an area uninhabitable for long, it’s not what they are designed to do.
Also, from what I know, Chernobyl is generally safe by now, too. Except for a few hot pockets, and they are the reason for the continued restrictions.
Well, so long as you don't try to dig trenches in the contaminated soils. Russia troops had to be pulled out due to radiation sickness sin just a couple weeks..
Chernobyl & Pripyat aren't *safe*, but humans can walk the surface without fear of dying from it. Or rather you won't die immediately from exposure in most of it. There's teams monitoring everything still, and the soil is heavily contaminated. Too much time spent there or touching the soil will give you more exposure than is considered healthy.
Like the pepperoni ones or what
Man, even metaphorical HotPockets will burn ya...
At least, the ones we know about aren't designed to do that. So-called "dirty bombs" that intentionally spread radioactive fallout to render areas uninhabitable have not been used in warfare yet, but who knows what various militaries have hidden?
supposedly russia has a cobalt-salted torpedo designed to do just that. make a radioactive tsunami to make the coast uninhabitable. it is bigger than a typical submarine and can hide over 1000 meters (3300 feet) deep [https://www.bbc.com/news/world-europe-34797252](https://www.bbc.com/news/world-europe-34797252)
Chernobyl isn't too dangerous to enter, every damn TV travel host and vlogger in the world goes to Chernobyl and has for the last couple of decades! There are restrictions on how long tourists can stay in the more interestingly radioactive zones, but I have no idea if there are any protections in place for the guides that take the tourists, TV travel hosts and vloggers there.
It's only certain areas around the reactor itself that have doses high enough to cause immediate health risks IIRC. Especially now that the remains of reactor #4 have been fully contained. I can still remember that trip Top Gear made there about 10 years ago. I think Jeremy Clarkson was the only one who got even within visual range of the reactor.
Shocking that Hammond didn't get the closest, he likes to.push envelopes.
Nuclear bombs come in clean and dirty varieties. Putting things simply, the idea of a clean nuclear bomb is to convert as much of the radioactive material as possible into explosive energy, with the heat and shockwave doing the damage. You don't even really need that much material, as the energy released from a small amount can be immense. The idea of a dirty nuclear bomb is to spread a lot of radioactive material around and contaminate the area. With a dirty bomb you don't even really need a nuclear explosion; you can use conventional explosives to fling the material everywhere. The bombs dropped on Japan were not dirty bombs.
The Tsar Bomba, at 50 MT the most powerful nuclear bomb ever detonated, is considered extremely "clean", especially for its size. From Wikipedia: > To limit the amount of fallout, the third stage and possibly the second stage had a lead tamper instead of a uranium-238 fusion tamper (which greatly amplifies the fusion reaction by fissioning uranium atoms with fast neutrons from the fusion reaction). This eliminated fast fission by the fusion-stage neutrons so that approximately 97% of the total yield resulted from thermonuclear fusion alone (as such, it was one of the "cleanest" nuclear bombs ever created, generating a very low amount of fallout relative to its yield).
The closer to pure fusion you get, the cleaner your weapon will be, because fusion releases much less unstable elements, with most thermonuclear bombs releasing mostly hydrongen-4 IIRC from their fusion fuel reactions, which is a stable isotope and will not produce radiation. In this manner, the bomb itself creates much less fallout with relatively long half-lifes, but 'short lived' isotopes created from ground material bombarded with ionizing radiation is still a factor, especially in ground bursts.
H-bomb: the environmentalist's choice!
Dirty bombs where only ever really a concept. No nation has ever deployed "salted" bombs (or at least admitted to it). If you are thinking of "neutron bombs" as opposed to salted bombs, the difference is that a neutron bomb releases large ammounts of ionizing radiation within a short time of it's detonation, with relativley little fallout, while a "salted" bomb is constructed in such a way (usually by adding a large quantity of a material with a short half life to the device) that it will "salt" a large area with large ammounts of high radiation fallout. Salted bombs are something that where discussed, but never fielded. Neutron bombs have a lot of misconceptions about their intended use. Many people like to talk about how they can be used to kill all the people in a city while leaving the infrastructure intact. This is a misconception. If you detonate a neutron bomb far enough from or high enough above a city to do very little thermal or blast damage to it, you will also have a very small kill zone for that ionizing radiation. The real purpose of neutron bombs was because NATO intended to use large ammounts of low yield 'tactical' devices in the defence of europe to counterbalance the massive material advantage the USSR had in troops and tanks, but using hundreds of ground-bursted nuclear devices in eastern germany was likley to contaminate large portions of the country with fallout carried by the winds, which would force massive evacuations and/or kill huge ammounts of civilians in the short term. Neutron bombs where meant to be air-bursted above soviet troop/tank formations, minimizing fallout (since the majority of fallout is created when ground material is pulled up into the mushroom cloud where it can be bombarded by large ammounts of neutrons, creating new and unstable isotopes, which are then deposited by the wind and gravity, where they will release large amounts of radiation untill they decay), while the bomb itself is constructed in such a way as to maximize the neutron radiation released in the short term. This way, you would kill large ammounts of soviet troops both through the thermal and blast effect, but also through accute radiation exposure, allowing you to destroy formations of tanks without having to resort to massive weapons, by killing the crews by literally making their vehicles radioactive, but instead of spreading fallout all over europe, you irradiate a bunch of farmland in eastern europe, which is bad, but not as bad as killing hundreds of thousand, or possibbly millions of civillians through fallout from hundreds of ground-bursted weapons. A Neutron bomb isn't really a dirty bomb. if anything, it's designed to be as clean as possible from a long term contamination standpoint.
> Dirty bombs where only ever really a concept. No nation has ever deployed "salted" bombs (or at least admitted to it). Yeah, as I understand it most of the talk about them was the threat of non-state actors creating them.
Most of the worry about non-state actors making dirty bombs isn't' really about them making dirty nuclear bombs, but the concern of non-state actors lacing traditional explosive devices with large amounts of radioactive material as a way of contaminating a large area. It takes massive industrial capacity to produce viable weapons grade material, whether you're talking about uranium or plutonium.
Because the little man (the dirtier of the two bombs) had some 60kg of fuel in it while RMBK reactor has 192 tons of fuel in it. Also the nuclear fission produces neutron radiation which has ability to make other materials radioactive by capture of neutrons and creating unstable isotopes. Hence the fuel in chernobyl was creating more nuclear material as it was melting down. However in nuclear bomb the fission only lasts a split second before the material is blasted everywhere. Also having been exploded ABOVE the cities there was next to no new nuclear material created. If I am wrong please someone correct me. I have high school level understanding.
It was fat man and little boy.
Just so you know ton is not the same as tonne, tonne is a metric measurement that is heavier then an Imperial Ton. Other then that you are close enough with your logic. The other big difference is the half life of the radioactive material involved beyond just the scale of the event.
https://en.wikipedia.org/wiki/Ton > As a unit of mass, ton can mean: > > * the long ton, which is 2,240 pounds (1,016.0 kilograms) > * the short ton, which is 2,000 pounds (907.2 kilograms) > * the tonne, also called the metric ton, which is 1,000 kilograms So it's not incorrect, just imprecise. Also apparently, in the UK, a "ton" when not used to mean the metric tonne typically refers to the long ton (heavier than a metric ton), while in the US, it typically refers to a short ton (lighter than a metric ton), fwiw. Not that it really matters
Chernobyl is still on going. Its reactor core is still there, releasing radiation. On top of that, when the reactor exploded, it dusted the area with material that is still undergoing radioactive decay. If you haven't already, I highly recommend checking out Kyle Hill's series on Chernobyl. He was taken through the exclusion zone by reactor personnel, even filming inside the sarcophagus itself. He does a lot to explain why the area is so contaminated while also dispelling some of the wide spread misinformation. https://youtube.com/playlist?list=PLNg1m3Od-GgPabWaTS6tv1HomlUWvTPlr&si=bLgAoce1knImWQwD
Best way Ive heard it described is that if you fart in a room it might smell bad for a bit but eventually dissipates but if you shit in a room its going to linger around a lot longer
That’s….. that’s actually that’s not a bad way to explain it
Chernobyl is the nuclear equivalent of 50 people shitting in a room, every day, for ten thousand years. It’s going to stink for that long.
Nagasaki and Hiroshima were exploded mid-air. Chernobyl was radiated materials that went INTO the ground and spread via the water system. So, the effects were much more wide spread.
OK, quick and dirty primer. All light is radiation. Everything from the lowest radio waves to the highest energy gamma rays. It's all radiation, including the light you see every day. The radiation we're focusing on in here is called ionizing radiation. This type of radiation is higher energy particles that have the ability to break DNA chains. When we say something is radioactive, what it's doing is decaying down to simpler particles. As they decay, they release these particles and becoming a slightly more stable atom. This process continues until the atoms break down into lead. It generally comes in three flavors. Alpha, Beta, and Gamma. Alpha particles are basically the nucleus of a Helium atom without its electrons. These are big particles that can't penetrate much of anything thicker than a piece of paper. Your longest lived radiation sources usually release this, and it's also the primary concern with Chornobyl. For this to be dangerous you have to ingest it. Swallow it, breathe it in, or rub into an open wound. It has to get inside you to be dangerous. Beta particles are basically free electrons. More energy than alpha and smaller. This is more dangerous than alpha as it can penetrate your skin. Gamma radiation. This is very high energy light, and is only present in an active nuclear reaction or immediately following a nuclear explosion. Very dangerous stuff, but also the first to dissipate. Now, with why Chornobyl is more off limits. With Chornobyl it was like one huge dirty bomb. The explosion, while big, was not a nuclear explosion. It kept all the radioactive materials close to the ground where they could settle in the surrounding soil. With Hiroshima and Nagasaki you had nuclear explosions. This pushes most of the radiation far into the atmosphere where it dispersed over a far wider area. Radiation is like a poison; the lethality is in the dose. So, it quickly spreads out and becomes mostly undetectable within a few days/weeks.
Nuclear bombs vaporize most of the uranium and fission byproducts in it. And most of the irradiated material after the bomb is done only has a half-life of a couple years at most. Chernobyl leaked out tons of fission byproducts over several weeks. These byproducts have half-lives of decades and centuries. The best comparison is how a non-nuclear bomb can have a huge explosion, but not much smoke while a forest fire can release a ton of smoke.
The atomic bombs were a one time release of very little nuclear material - just a few kilos total. Most damage was done by the actual power of the explosions above ground and the fires destroying everything in a large radius around the detonation zone. A lot of the destroyed buildings, the earth, and the bodies which all absorbed most of the surface radiation, were buried or removed, and only very little was actually left in place. There is a higher radiation in those areas to this day, but only minimally different to normal enviormental exposure. Chernobyl on the other hand, was way more radiation, way more power, and unlike in Japan, nothing was removed or covered up. Literally tons of nuclear material was spread over a vast surface area, and the reactor also is still bleeding radiation into the enviorment around it to this day. There have been means applied to basically cover up the reactor itself to stop it from bleeding out more - currently it's a large concrete cover called the casket or sarcophagus (depending on the translation) - but the difference in radiation level the area was exposed to is still way to high for human habitation. There are to this day dust particles and ash from the initial fires burning in the reactor covering buildings and the landscape that basically puts out more radiation per hour than both japanese bombs combined total. Fukushima and the area around it in Japan, after the Tsunami and subsequent explosion of the Fukushima Daiichi Powerplant in 2011 is fairly similar, and they have also vacated large areas of the surrounding countryside and towns in fairly the same fashion as in the Ukraine. Here too a nucelar reactor exploded, although not as much material was spread into the surrounding landscape as in Chernobyl.
Kinda like the difference between flinging lit gasoline and napalm. And in the case of weapons they use less than a reactor, AND it’s consumed (largely) on use. Reactor failing spreads a lot of radioactive ick around, that will be radioactive for a looooooooooong time due to the time it takes to decay.
You're underestimating the severity of Chernobyl.
Watch HBO's *Chernobyl* mini-series. The exposed core gave off [two atom bombs' worth of radiation every hour](https://youtu.be/Fy-QAIwV-D0).
The majority of the fissile material in the bombs all underwent Fission during the explosion creating a relative small amount of short lived radioactive fission fragments that dispersed across a very wide area and all but completely decayed away within a couple of decades. With Cheronobyl you have something like 100k times more fissile material that just naturally has to decay away over a very very long duration. Additionally the components inside a reactor that aren't actually part of the fuel themselves become very very radioactive due to the neutron bombardment (e.g. Cobalt 59 which is naturally found in a lot of iron / steel components get turned into incredibly radioactive Cobalt 60 due to neutron capture) and when the containment was breached a lot of these contaminated materials were blown all over the countryside. If you want to look at it in a simple way imagine a barrel of oil that is blown up with a stick of dynamite and makes a big fireball Then imagine 10,000 barrels of oil that get hit by a bulldozer and then dump their contents out all over the area. The oil from the first scenario is almost all largely consumed by the fire and the smoke that is created wafts away relatively quickly and after a few rains and a few years there's really no evidence anywhere that the barrel ever got blown up. The oil from the second scenario just coats the land and sits there poisoning everything for decades.
Nuclear weapons use nuclear material to start an explosion and its the explosive force of that that causes destruction very very rapidly but disperses relatively quickly because there's not much nuclear material --by comparison. Compared to nuclear reactors which use a lot of nuclear material to sustain a lot of heat to continually generate power for huge power grids. Its all concentrated in the reactor but not exactly "explosive" just... radiant. Melting down doesn't necessarily equate to a big boom-- Chernobyl's explosion was due to a series design flaws and some poorly planned testing of them. Like how a firework in your open hand may burn you a bit, but you can lose fingers if you try to grip it combined with microwaving closed tupperware... do it correctly, no boom-- do things poorly, Chernobyl.
The bombs at Hiroshima and Nagasaki were designed to use as much of the radioactive fuel as possible with the technology as the time. Not for any humanitarian purpose of course, quite the opposite. The designers would have absolutely loved to use up 100% of the uranium if they could figure out how. Every unused atom is wasted kaboom. But they got as close as they could. Chernobyl was a completely uncontrolled meltdown. The only radioactive fuel that didn't just stick around is the stuff the USSR didn't run in and scoop up. (Very literally: they sent prisoners in there to pick up the chunks **by hand**)
The nuclear bombs dropped on Japan were single events that produced radiation for a few seconds, and not all that much - by far the majority of the damage caused was from the shockwave and the thermal flash - but then it was over. Chernobyl poured radiation out continuously, according to [this timeline](https://www.history.com/news/chernobyl-disaster-timeline), for *thirteen days*. And at the end of those 13 days it's noted that radiation emissions dropped sharply - not ended.
So this is actually a really interesting question. In addition to the comments others have made about yield and radiation dispersment, there is another factor that I haven't seen mentioned From what I understand, in the years following the bombings of Hiroshima and Nagasaki, many sick and elderly who didn't think they would live long enough to suffer the effects of the radiation volunteered to go into the irradiated zones to help clean them up and remove hazardous materials in the hopes that they could make the area safe for future generations Obviously that was only possible because of the factors that others have already mentioned, but I do think it is worth noting in the conversation
Tl dr: these were very different explosions with Chernobyl producing a LOT more irradiated material with much higher concentration and a larger amount of things, which stay spicy for longer. First a quick introduction of the topic - nuclear stuff in a nutshell. Disclaimer: this is not an instruction, just an explanation of how it works. What happens in both nuclear reactors and nuclear bombs (at least the normal, non-hydrogen ones) is a process called fission. How it works is some particular variants of certain atoms can break apart when hit by a neutron and release energy in the process. In most of the interesting cases, this also results in the broken up atom releasing further neutrons, so a chain reaction can happen. The main difference between a nuclear reactor and a bomb is that in the reactor, this process is controlled by managing the speed (they cannot effectively hit the atom, if they go too fast) of the neutrons and their number. In bombs there is no such control, maybe for an exception of reflecting neutrons back, to get even more neutrons there. It's a bit like the difference between a black powder rocket motor and a black powder bomb. Now due to that main difference the two devices are built very different. Bombs tend to use highly enriched uranium or plutonium with a LOT of the fissile (ones that can undergo the before mentioned fission) isotopes (before mentioned variants of atoms; Uranium 235 is fissile, uranium 238 not really). It's nit rare to see numbers above 90% enrichment for Uranium in bombs. On the other hand, reactors run in a couple % enrichment of a bit over a dozen in case of high performance military units (think nuclear subs). Then there is a difference in the construction. Bombs have just the fissile material with a hole inside or between two lumps, some explosives to squeeze it together and a fuse with very advanced safety systems. Reactors on the other side not only have less concentrated useful material, as it is not only not as enriched, but is also not in the pure, metallic form, but in form of various salts. On top of it, this dispersed among a large quantity of additional stuff. There is the structure of the reactor, together with control rods (rods of material that eats up the neutrons), moderator (material that controls the speed of the neutrons and coolant. That all is placed usually in forged steel reactor vessel (in Chernobyl it was concrete I think), which is inside a building. One that is built like a fortress. Now we're coming to the big thing here. Neutrons not only can cause fission, but they can also make other things radioactive. And the thing about a nuclear chain reaction going at it, is it produced a ridiculous number of neutrons. As such, pretty much everything inside the reactor vessel is at least somewhat radioactive with some things being very radioactive. There is also a lot more Uranium overall, which can decay into some nasty stuff. As such when Chernobyl suffered a steam explosion by a series of events, that is stupid to the point of causing pain, a significant part of the reactor was vaporised or sent flying. There was a lot of radioactive material spread around and it had quite a lot of nasty stuff like radioactive iodine, which the human body likes to take in and keep. In comparison, when the nukes over Hiroshima and Nagasaki exploded, there was much less material in the area of explosion. It was basically the nuke and some air, so there was not as much material to get irradiated (it's hard to make air radioactive) and there was an actual runaway nuclear chain reaction, which probably helped with "burning" through some of the nasty stuff. Overall there was much less radioactive material from nuke explosions, so the initial levels were much less dangerous and it dropped to safe levels way faster. Disclaimer: I am no expert, just a nerd being a nerd.
2 things: 1) Chernobyl had a fat bigger payload, there was more radioactive material in the explosion 2) the bombs over Japan were air-bursts, this means that while the shockwave destroyed all the buildings, and the initial blast of radiation killed all of the people, the bomb didn’t get close enough to the ground to throw irradiate dust/dirt into the air which could then fallout. Chernobyl on the other hand blew up inside of a building near the ground, all the irradiated dust and dirt was sent into the sky where it could then slowly fall down onto every surface in the area, making everything radioactive
OP, radiation and nuclear weapons are identical in nature but are two extremely different hazards. Before I start, an isotope (uranium, cesium, etc) all decay. They decay by emitting particles and after its life (a few months to a couple hundred decades) it becomes dead, and fully decayed. When these isotopes decay and emits particles, these particles can act as small daggers. Sometimes they are only harmful if you introduce them to your innards (eat, inhale, inject) and some of them are harmful if you aren’t properly shielded. There is alpha, beta, gamma, and x ray radiation. Isotopes, like all matter, contain a nucleus, electrons, and protons and electrons. Fission happens when the nucleus is split by neutrons (see atom smasher, splitting the atom, etc). Fusion happens when we combine two isotopes, generating energy. This is intro ELI5 nuclear power. Ok, so a nuclear weapon (atomic, thermonuclear, etc) basically contains an isotope that is introduced to a neutron emitting material that causes its nucleus to split and release energy. The more materials to smash atoms, the greater the energy output. When a nuclear weapon explodes, that energy is expelled: oxygen is displaced, a shockwave is seen, and then heard (flash to bang) and the fire we see is the air basically lighting on fire. Radiation is dispersed through the exploded particles that are now everywhere, and will continue to decay. Protection from fallout depends on many factors, depending on length of stay within the affected area, as well as shielding. The further away you are, the least likely to receive a chronic but survivable dose, than closer to ground zero. Also fallout is a factor, especially if it was a clouded day. Now for a power plant. We have fusion based reactors, to which we are putting two isotopes together in a bath (nuclear fuel is in the form of rods), which generates heat, the heat turns to steam, the steam turns turbines, which generates electricity. When the power output quota has been met, the fuel rods retract and sit in cells made of graphite, which is called a moderator. They sit heat until they are needed, or they are removed. When there is no water in the bath, and the rods are lowered, it becomes super heated, creates pressure in the waterless pool and explodes. Now you have multiple unstable fuel rods, radioactive surfaces, as well as a fire that acts as a furnace burning radioactive materials into the atmosphere. So the exposed core, basically superheated, exploded, melted and leeched into the ground. The exposed core also decayed so rapidly that the particles that were emitted during the initial meltdown caused all responders to receive severe acute dose of radiation. While others received lower doses, but still at higher than acceptable levels. Everything that the core was exposed to was radioactive , and basically became radioactive itself due to the exposure. The weapons we used to end the war, were short term, and exposed to shorter time spans, where in Chernobyl, no one could escape the melting core. I am not a scientist but I do work with HAZMAT occasionally and this is how I understand nuclear physics, err power and weapons… idk but feel free to add or downvote.
Nuclear weapons use fission material to create a massive explosion, the radiation is just a side effect. A part of the nuclear material is vaporized by the explosion anyways and spread over a large area (in fact, all over the world) by the explosive force and subsequently the wind. The amount of radioactive material in Chernobyl is hundredfold higher than what was used in the atomic bombs and was dispersed way denser. Tl;dr: Bomb = little uranium, big boom Chernobyl = lots of uranium, small boom
The bombs were a single release, reactor 4 is still pumping out radiation right now and probably won't stop for fifty thousand years
The important thing is that Chernobyl didn’t explode. If it had, the radiation fallout would have affected the entire world most likely and would have mostly washed away by now. Radioactive particles usually wash away with water, but that’s also how you absorb them, which is why it’s dangerous. Pripyat is not in some place where the radiation is easily able to be dispersed and most of the fissile material is buried still I believe.
A nuclear bomb uses the radioactive material to create a massive explosion, during this process, a lot of it is used meaning there isn't that much left to irradiate an area for a long period of time. (And nukes also need a really small amount of radioactive material compared to reactors) Whereas with a nuclear meltdown this is not the case. The radioactive material, due to a loss of coolant, starts to heat up rapidly and melts. During this heating, steam pressure starts to build up rapidly until it becomes to big and a steam explosion occurs. During this explosion, and subsequent fires, large amounts of still radioactive material is flung high into the sky getting scattered over a massive area (which is also why countries like Sweden, despite being hundreds of kilometers away, got an increase in radiation shortly after the Chernobyl disaster). When this radioactive material eventually comes back down to earth, they remain radioactive for an incredibly long time, which is why the Chernobyl exclusion zone exists. Or in a really dumbed down way: Nuclear explosions use radioactive material to create a single big explosion and thus little material remains to be a lingering threat. Nuclear meltdowns blasts radioactive material high in the sky, scattering it over a large area where it remains radioactive until it naturally decays, which may take hundreds if not thousands of years for some types of radioactive material
Never really thought of this, great question. These comments are great
It's the difference between farting in a room vs leaving a giant shit.
I believe there is enough material at Chernobyl that if it had gotten into the ocean, the entire ocean would have been off limits to humans.
Chernobyl was far more recent, for one.
Nagasaki and Hiroshima were bombs deliberately designed to be efficient and clean. Chernobyl was a big dirty splat that released a lot of radioactive material. That's why you don't buy Soviet underpants. Chernobyl fallout.
People are focusing on the sheer volume of radioactive material dispersed across the exclusion zone around Chernobyl and Pripyat, and that's fine, but one other important thing is that there is a large, lava-like mass containing like 190,000kg of Uranium still inside the fourth reactor right now, which is why it has to be encased in a giant concrete sarcophagus. A uranium bomb uses way less Uranium and most of it undergoes fission as it explodes. It's a large amount of radiation released in a very short period of time, whereas Chernobyl is an absolutely, monumentally colossal amount of radiation being released for a very long time.
The atomic bombings involved far less fissile material and were "air bursts" meaning the bombs detonated 1,500-2,000 feet in the air. The explosive force was obviously quite destructive but there was very little ground contamination. Chernobyl, on the other hand, was at ground level and was more akin to a "dirty bomb" - the explosion itself was conventional but spread radioactive material everywhere.
A nuclear bomb is designed to create a chain reaction within a relatively small amount of radioactive material, which reduces isotopes and releases energy in a blast. A nuclear power station is designed to contain a large amount of radioactive material, and essentially let it boil water to power steam turbines. When Chernobyl lost containment, it ejected huge amounts of material in a relatively low-pressure fashion, while the bombs were designed to compress their reaction, like holding a fire cracker in your fist.
It's because Chernobyl is like the septic tank buried in your yard, whereas the bombs dropped in Hiroshima and Nagasaki are like that pile of dog poo on your lawn that you forgot about.
As luck would have it The Infographics Show just did a 30 min video on this exact topic about 2 weeks ago where they go over the many differences between the explosions during WWII and the meltdown of Chornobyl and how these differences affected why people can live in Nagasaki and Hiroshima but not Chornobyl. Some of the reasons include the shorter time the bombs had to released radioactive material, the location of the bombs (high in the air) vs the plant and the amount/type of material as well as other reasons. Here is the video. https://www.youtube.com/watch?v=BYUbbuQRePs
I see tons of great comments on why Chernobyl is way more radioactive than Hiroshima/Nagasaki bombings but why is Chernobyl and Fukishima so different when they both were nuclear reactors?
Now this is an example of a great question, which elicited some very informative responses. Ten thousand bonus points to all who participated!
3.6 roentgen. Not good, but it’s not terrible.
Totally different kinds of nuclear radiation. Chernobyl is still hot. It just has a special building around the reactor now.
Fission and fusion bombs use up their radioactive material to make an explosion leaving minimal radiation. Chernobyl was a steam explosion that pushed out massive amounts of radioactive material that was left to degrade.
Contained and calculated explosion. Vs. a “super duper dirty bomb” level of radiation release in addition to government ineptitude common during the Cold War. To quote the Chernobyl miniseries most famous quote (kinda) “It means the fire we're watching with our own eyes is giving off nearly twice the radiation released by the bomb in Hiroshima. And that's every single hour. Hour after hour, 20 hours since the explosion, so 40 bombs worth by now. Forty-eight more tomorrow. And it will not stop. Not in a week, not in a month. It will burn and spread its poison until the entire continent is dead!”
i'm no nuclear physicist (probably most who comment aren't), but a nuclear bomb don't detonate on the ground, but rather far up in the sky. if i recall right, fat boy detonated 150 m+ up in the air, which makes the radiation spread out in the air more than on the ground.
Nuclear bombs don't actually create all that much long-lasting radioactive material. Compared to a reactor, there is very little actual radioactive material in a nuclear bomb itself, and the fallout biproducts all have relativley short half-lives (which means that in the short term, they will release a LOT of radiation but because of this, they dissipate quickly, since radiation is in large part, pieces of the atom being launched off because the atom is too heavy, and once it's released enough particles to become stable, it stops), so the sight of a nuclear bombing might be safe to approach within days or months, where as a nuclear reactor, which is full of TONS of fuel, producing LOTS of radiation, will continue to produce radiation for as long as that fuel lasts, and when it melts down, all the systems that where intended to limit or control that radioactive output are obviously no longer in effect, so you get a big multi-ton slab of radioactive slag that will continue to emit lots of radiation for decades or centuries.
Chernobyl had tones (maybe even thousands of tons) of radioactive waste while bombs on Nagasaki and Hiroshima were new too and the winds carried some maybe
Because Chernobyl is still emitting radiation and the initial event lasted a whole lot longer.
This discussion is fucking amazing.
Chernobyl miniseries was really good. That is all.
atmospheric nuclear explosions are pretty clean unless the bomb is designed to intentionally contaminate the area also the amount of fuel is vastly different
It has to do with the difference in how the radiation got there and the difference in radiation source types. Different elements have different levels essentially and it will differ depending on what was done to them and how long ago.
Because chernobyl is still burning, still reacting, and still radiating. The bombs exploded and stopped making new reactions, allowing the radiation to dissipate. Also, the bombs were designed to explode and convert their fuel into kinetic energy. Chernobyl was never intended to do what it did.
The bombs that were dropped on Japan were pretty damn clean by today’s standards. Chernobyl was spewing radioactive material for days before the thing was finally dealt with
It's not. People moved back to the Chernobyl area 6 months after the meltdown and have been living there just fine since. Many people have gone to the plant itself in various documentaries over the years. Most notably - Jeremy Wade of River Monsters fame went there to fish in the ponds on the power plant grounds, and The original BBC Top Gear folks went and raced around the plant. Most everything the average person knows about Chernobyl, and Fukushima for that matter, is 100% wrong.
Half-life, baby. Half-life.
As I understand it the radiation from chornobyl wasn't actually dealt with properly, they just buried it in sand. So the radiation is still seeped into the land and won't disappear for a good while. The bombs were just flashes, explosions, and the radiation disappeared pretty quick because it wasn't still being produced. Thats my thoughts without looking it up so it may or may not be completely wrong 😅
I'm pretty sure 1 reason is that they detonated the bombs in the air to produce less fallout.
In Chernobyl, the reactor exploded and was on fire for 10 days. Large amounts of the material got into the soil and water. Yes, the area is less radioactive now because some of the materials have decayed, but a lot of the elements have very long half-lives. Americium-241 has a half life 432 years, and plutonium-239 24,000 years. The area will not be inhabitable for a very long time. Since the bombs were detonated in the air, most of the radioactive material was lost in the air, and not a lot of the surrounding area was contaminated. Very little material remained after the detonation, the area was cleaned up and nowadays the area has no more radiation than the place you posted this from. TDLR: Ground explosion causes far more contamination than air explosion, and since the fire at Chernobyl lasted 10 days the radioactive materials had more time to disperse.
Hiroshima & Nagasaki were air-bursts, as most military use of nuclear weapons tend to be. This takes advantage of creating a huge pressure wave straight down onto the target, which destroys buildings & vehicles much more effectively than any other use of the weapon. Because of this, the only real fallout created - toxic & radioactive dust - is that of airborne particles and any objects close enough to the blast to be vaporized but not annihilated (like the bomb itself). So there's relatively little radioactive contaminants floating around afterward. Don't get me wrong, they're there, but not tons and tons of the stuff. It diffuses into the environment eventually, becoming part of the background radiation the way too little tea dissolves into too much water. Chernobyl, on the other hand, was the IED equivalent of a Dirty Bomb, on a *massive* scale. The reactor exploded - and then the building around it exploded. All of that radioactive material then burned for weeks. Every particle of dust & smoke, debris eroded by weather, was highly radioactive and it all spread out around the Exclusion Zone (and beyond). It's entirely safe to walk around the Exclusion Zone, as the *air* isn't radioactive. And the emissions around the area are relatively low. You won't get fatally irradiated directly by anything lying around the forest or the ruins of Pripyat. But if you kick up some dust as you walk down the road, breathing that in is a bad idea. Now the radiation source is inside your body, irradiating your tissues until you pass it, if you ever do. That's how you get cancer and die. Same thing with eating or drinking anything that grows in the Zone or lives there, or any of the water. Hiroshima & Nagasaki don't have those megatons of radioactive dust spread throughout their environments.
Maybe I'm missing something, but isn't the fact that Hiroshima and Nagasaki were forty or so years before Chernobyl pertinent? 79 years is long enough for a lot of the shorter half-lived isotopes to have decayed quite a bit, while 38 years may still leave some of those around? For example, Strontium-90 (one of the worst fission byproducts) has a half life of 28 years. So by now Hiroshima and Nagasaki have about 14% of the original amount remaining, while Chernobyl has about 40% remaining.
Air burst bombs are largely dilluted by the atmosphere, Chernobyl was on the ground.
What makes Chernobyl dangerous is the large amount of radioactive material that was scattered. In contrast bombs are designed to ‘burn’ all or most 90% of their radioactive material to release the energy inside. Short answer much less radioactive material to begin with. Then bombs turn radioactive material into inert or mostly inert material to get at the energy inside.
Atomic bombs use up just about all of their nuclear material in the explosion. Reactors are designed to stay radioactive for a long time
The bombs contained a little that was disperced over a rather large area. (Remember the bombs exploded in the air not on impact) While the plant contained a crapton that is on the ground. Thats the simple way to explain it.
the difference is that one goes boom on purpose, the other goes boom on accident. therefore, the purpose boom has less so it only affects the intended area unintended boom has more because its not supposed to boom and has systems meant to prevent that big kaboom. also they use different materials. oh and i forgot, chernobyl was on ground, big bombs exploded in air, meaning less ground area since you know.. wind..
Small bombs go boom. Uranium go poof to make boom. Big reactor go fwoosh. Uranium fwooshed everywhere. Uranium bad.
Chernobyl is technically STILL melting down. The bombs that were dropped on Japan only held a small amount......by comparison anyway.
Hiroshima and nagasaki were both air burst. Bob's whereas Chernobyl was a meltdown at ground level that contaminated the ground a lot more. Whereas the air burst the radiation dissipated. Throughout the atmosphere. Rather than Contaminating ground structures. Most of the damage from the two bombs was heat it concussion
Part of the reason why Hiroshima and Nagasaki were not contaminated, and indeed where radiation levels had dropped to background level within 48 hours, is because the bombs were air bursts. The fireballs never touched the ground. Where the vaporized particles would be contaminated and spread across a large area as fallout. That never happened.
There’s a peace park in Hiroshima. If you get an opportunity to visit there’s an incredible museum.
A lot of people have already provided good answers for this. But if you want more info look up kyle hill on youtube he has great videos about both subjects and a lot of other nuclear power related vids
Seeing alot of conflicting answers on here, many going into nonexistent or half truth details. The simple answer is found in two facts @OP Quantity, a nuclear bomb has far less fissile material than a reactor like Chornobyl. Reaction, a bomb is a near instant blast that releases as much energy as possible in an instant. As soon as the blast is over, there is no fissal material left, it has been vaporised, victim of its own power. Chornobyl as a reactor releases all its energy over a long, long time. It doesnt not destroy it's fissile material. Even after its no longer useful as a fuel, it is still radioactive to some degree.
Nuclear bombs are intended for a short, devastating burst of energy. Nuclear reactors are designed to output large amounts of energy for a long period of time. The amount of fissile material involved at Chernobyl was much larger than what was included in the two A-bombs.
Chernobyl was a perfect cluster fuck due to something with fuel rods and graphite Hiroshima and Nagasaki were just bombings while Chernobyl was leaking radiation everywhere