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"Nuclear Archaeology" Inspires Replica of Hiroshima's Little Boy
James Cho writes "Through a decade of painstaking reverse engineering, trucker John Coster-Mullen built the first accurate replica of the Hiroshima bomb. His work yielded a new history of the first nukes, 'Atom Bombs: The Top Secret Inside Story of Little Boy and Fat Man,' with historian Robert Norris saying, 'Nothing else in the Manhattan Project literature comes close.' Philip Morrison, one of the physicists who helped invent the bomb, deemed it 'a remarkable job.'"
How soon until homeland security shows up accusing him of terrorism?
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The guy went through declassified government documents to gather all the information he could find (including design information), and went from there. I don't think this is anything like reverse engineering.
If he "reverse engineered" the bomb, wouldn't it mean he put the design together based on blast data from known explosions of this particular device?
#DeleteChrome
A working replica would be dangerous and surely illegal.
If I had a working replica of a nuclear bomb in my basement, I don't think I would give a rat's ass about whether it was dangerous or illegal.
If I did have a nuclear bomb, I would not have a problem.
Some other folks would have a problem.
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Hopefully not that accurate.
The Hiroshima bomb was a very simple "gun" design. Plenty of published info on it. It used a navy gun barrel cut down to size, a U235 doughnut target, a polonium initiator, and a U235 projectile. Mighty simple. Any chopper shop could build one, with the exception of getting the Polonium and U235.
This design was abandoned as it had many drawbacks-- it used about 8 times more U235 than absolutely necessary, there was a 7% chance of a fizzle, and there was no way to make it safe.
But it had the advantage that it was dead-simple and guaranteed to work, well 93% of the time.
Now if he made a replica of Fat Man, that would really be something.
There are a lot of stories that appear on /. in which I have absolutely no interest. (The same could be said by practically anyone here.) So you know what I do when one of those stories comes up on the front page? I don't click on it. Easy, simple solution -- let the people who do care about that particular story talk about it, and go find something I care about to read and comment on instead. Everybody wins. It's not that hard a concept to grasp.
The correlation between ignorance of statistics and using "correlation is not causation" as an argument is close to 1.
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One thing to keep in mind when you read statement such as "Destroy R. Worlds, former Director of Bomb Design at Los Alamos, said of Joe Amateur's work 'That's very well-done'" is this: reading between the lines of many interviews, articles, and books about and by former weaponeers they give out a lot of misleading, and/or misdirecting, information about how _exactly_ devices are built. They talk openly about the general principles and their scientific and political implications, but when the discussion/interview/chapter turns to the actual details of design, well, the replies turn a bit fuzzy or clever. I suspect that either by explicit training or shared values they give away very little and much of what they say would deliberately lead anyone following down the wrong path.
sPh
Besides, a lot of the difficulty in making even an inefficient nuclear bomb at all obtaining the weapons grade fissile material.
I'd say that the vast majority of the difficulty is obtaining the fissile material. Weapons grade uranium/plutonium doesn't exactly grow on trees. Creating it yourself (and preventing anyone from stopping you) takes the power of a government.
This has essentially been the policy to control proliferation for 60 years now. Stopping the knowledge of the design details is merely security theater.
AccountKiller
From the article: "Actually, he said, nothing about the bomb is secret. He smiled and added, 'The secret of the atomic bomb is how easy they are to make.'"
Its a little sad to skim through the posts on this story and find pretty much all of them are lame.
Its a long article but its really a fascinating read and I'm guessing almost no one did. It makes a couple really insightful points:
A. All of the U.S. governments obsessive secrecy about nuclear bomb technology is pure security theater. The hard part is mastering the fuel cycle. If you can acquire the fuel or master the fuel cycle, making the bomb is pretty easy.
B. Much of what we read and take for authoritative is in fact garbage. There have apparently been a number of works on Fat Man and Little Boy, often by well educated and authoritative authors that were apparently complete nonsense. It just took an obsessive photographer/truck driver with no college degree to debunk one authoritative work after another. In particular apparently everyone thought the Uranium bomb was a female target shot with a male shaped projectile because thats the way people expected it to be, when in fact it appears it was the other way around.
One also wonders if the U.S. government intentionally propagated nonsense in these "authoritative" works thinking it would set back some aspiring bomb maker. For example, in one work it apparently said the barrel in the Uranium bomb was made of wood which was apparently pretty comical since it had to contain the explosion of several bags of cordite.
@de_machina
Actually, it is a pair of nested cylinders, and the rationale behind it is brilliant.
To get the biggest possible boom, you want to bring together the largest possible mass of fissile material. Problem: if you accumulate too large a mass, it starts a chain reaction on its own.
But if you form that mass into a ring shape, and make the hole in the ring large enough, you create extra surface area for neutrons to escape, but the gap is too big for them to have sufficient energy to split an atom on the other side of the gap.
For a given outer diameter (fixed by the inner diameter of the bomb casing) the maximum mass of fissile material is obtained with a cylinder whose height is determined by the mass on the "side" of the cylinder nox exceeding criticality. A mating cone shape results in a smaller usuable mass.
So why make the projectile hollow instead of shooting a slug into a hollow target? Because the sides of the gun barrel constrain the movement of the projectile and ensure that the mating surfaces are aligned.
It's actually, for such a "crude" design, brilliant engineering.
DG
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Get it straight.
The US government does not confirm or deny comments on classified technology. Nuclear weapons are classified. So if you write a book that is full of crap on nuclear bombs, all of the experts will general work for (or have worked for) the government and will not be able to comment on it.
Thus, people who are not in "the know" will read the book and say "Gee, this is really great stuff, very accurate." Meanwhile those who actually work on these weapons and who have security clearances will buy the book, read the book, laugh about the errors with each other... and not talk about it to the general public.
It's easy to be a self-proclaimed expert when all the real experts can't comment and you can't actually demonstrate that your technology works.
And finally, you really think making a bomb is easy if you have the fuel? Do you have personal experience here? Keep in mind you don't get a lot of testing opportunities with these things, and diagnosing what is going on during the explosion is also quite involved. There's a big difference between assembling your nuclear material to generate some nuclear yield and actually generating significant nuclear yield.