So I’ve watched Oppenheimer and a recurring theme in the movie was how tedious task it was to get fission material (demonstrated as filling a large fish bowl by marbles). All they manage to collect in two year period was just enough for two bombs. but fast forward few years US have a complete arsenal of bombs to flat the earth. I understand they must’ve innovated a method and the exact method maybe classified, what i’m interested in is knowing what was the obstacle(s) for this and rough idea of how they might’ve overcome it.
In: 450
Can someone please Eli5 how to create a nuclear bomb like in detail with how to get the materials. Dear NSA, I am kidding.
You are on a beach, throughout the entire beach is one tablespoon’s worth of salt mixed in with the sand.
Your job is to collect all that salt from the sand, so you and some friends go picking through the sand in the beach with tweezers, individually inspecting every grain of sand to see if it’s a grain of salt. Such a process could take you and your friends their entire lifetimes.
Instead, you build a fantastically expensive machine that can separate the salt out of one shovelful of sand every 24 hours. You build a dozen of these machines, and with these machines, it will take you a year instead of your entire lifetimes to get that salt.
Replace the salt with enriched uranium, and the salt separator with the Uranium enrichment factories and that is an example of effort required.
The Uranium Enrichment factories cost billions of dollars and had to have a city built around them to run them, it was massively faster at making enriched uranuim than older methods.
We had never done it before. We had to build up every part of it from scratch. Uranium had never really been useful until then, so there was no infrastructure to collect, store and refine it. All those things had to be created. We also didn’t know where a lot of uranium was, so we had to find it. When we did get it our refining processes were not efficient so we lost a lot the uranium that we could’ve kept today.
Once we had these systems and the procedures we developed in place, it became much easier to do. That doesn’t mean its easy to do, mind you. Its just easier than it was.
An interesting tidbit Oak Ridge is said to have consumed 14% of the electricity in the United States between 1943 and 1945.
I think you misunderstand the size of the US nuclear arsenal in that time.
A few years after WW2 we did not have enough to “flatten the earth”.
We had 300 in 1950, and most were small.
To this day the industrial centrifuging of uranium is a long and tedious process, far from trivial.
What would happen if you used non-enriched uranium or plutonium? Would the bomb be far less effective, or not react at all?
Your premise isn’t quite right, MAD wasn’t established until the 1960s, when ICBMs became prolific as a delivery platform.
There was no way to make just the amount of Uranium and plutonium they needed for just one or two bombs. The process is too slow so they had to make it at a huge scale to get the amounts they needed. They had to build huge industrial factories for it. The biggest in the world at the time with cities of 40000 people working on them (Hanford,WA & Oak Ridge, TN). Equal to building the entire US auto industry in 3 years. This was the slow part. Once they had that they knew that the US wasn’t just going to stop. It was never about building g just a couple of bombs. Nobody has ever created a new tech and then just put it back in the box. So once they had the system in place they could crank out enough U and Pu to make a bomb a week, and then a bomb a day. And then…
Side story, one of the engineers working on the methods of pre-gabbing the houses for the workers was a guy named Levit. After the war, he started cranking out quick, cheap houses for US Army veterans to buy with their new. G.I. Bill loans. They were called Levitown‘s and became the blueprint for the new suburbs that changed American cities from then on. We call these planned urban developments.
Also, the architecture firm that won the contest to create the urban plan for Oak Ridge was a little company called SOM (Skidmore, Owings and Merrill). Which is now one of the largest architecture firms in the world, and designed the Borge Khalifa in Dubai for example. (The tallest building in the world) the Oak Ridge project was the one that put them on the map, but you won’t find it on their website…
The atom bomb project didn’t just make bombs, it became the template for completely changing the whole way Americans lived. By the 60’s every American city was completely changed.
Natural uranium is almost completely U-238, less than 1% is fissile U-235. Enrichment for weapons grade needs to be almost 90% U-235. That’s a challenge. Next you need massive energy intensive processes and the correct chemistry to exploit to get good separation. One way now is to go through “yellowcake” from ore processing, to UO2 to UF4 to UF6 which then can go into the centrifugal separation unit. You only get a tiny amount back of high purity U-235. Which then needs converted back to UO2 or metal. “Depleted” uraniums is about 99.5% U-238 (natural is roughly 99.3% U-238). Basically it just takes a lot of work to get everything online and dialed in. Once you’re up and running okay, but until then it’s a lot to get established. UF6 is also highly corrosive (reacts quickly with moisture to give off hydrofluoric acid), so you need adequate safety and process controls in place. Many groups at National labs are not authorized to use / study UF6 despite how important it is in the purification process. Anywho it’s a pain in the ass, you’re isolating only a tiny amount of fissile material from the large amount of starting material and takes a while to get any new process online and producing at scale.
It was never trivial, the US spend like 25% of GDP at the time to build the infrastructure. Once we had massive industrial capacity and importantly breeding type reactors functioning of course we were able to rapidly produce fissile materials.
Latest Answers