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A truck driver uncovers secrets about the first nuclear bombs

newyorker.com

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Re: A truck driver uncovers secrets about the first nuclear bombs

#21

Post by amluto »

ChrisTheBore wrote: post #15
creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

>Does anyone understand what point is being made here? A cylindrical barrel is being fit over a fixed centre pin, rather than a pin inserted into a barrel. Makes sense when you realise that the moving component is inside of a similarly cylindrical bomb casing and that no fancy and complicated sabot and/or rail arrangement are required to keep it aligned and centered with the fixed pin. Most DC charging plugs work the…

I don't quite buy this reasoning. With a car charger, you indeed need to hold a fairly beefy contact in position so it mates with its counterpart. But in a car charger, there's no functional difference between the cable end and the car end -- sure, one is handheld and one is fixed to the car, but both ends need to secure their respective contacts.

With the gun-type bomb, suppose the final critical assembly has a 2"-diameter "male" part in a 3"-diameter formerly hollow ball. If the 2"-diameter "male" part were in a 3"-diameter barrel then, indeed, some mechanism would be needed to stabilize it. But I see no fundamental reason that the barrel needs to be 3" in diameter -- couldn't the "male" part just as easily be a projectile in a narrower barrel?

(I made up the 2" and 3" numbers.)

Re: A truck driver uncovers secrets about the first nuclear bombs

#22

Post by bouncycastle »

creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

Perhaps, since the larger piece would have more mass than the smaller, therefore it would impact with more force, and for a more sustained period, allowing it to reach criticality?

Re: A truck driver uncovers secrets about the first nuclear bombs

#23

Post by creato »

waheoo wrote: post #20
fermienrico wrote: post #18

Earlier quoted context omitted.

New Yorker, I found, is always obtuse, long-winded prose that fill up 14 pages where the whole thing can be, if it was written like a normal article, summarized in no more than 3 pages. It is prose porn for writers and readers alike. If I want good prose, I read the the Cabinet Magazine which is far superior in writing, curtness and straightforwardness while not affecting the charming and poetical aspects of writing.…

I don't even need to read the article to know this is going to be a long winded piece of popular bullshit. Just look at the title, manages to demean and belittle an entire industry that is entirely required for a functioning economy and society. Y'all wonder why blue collar America thinks we're stuck up entitled pricks? Maybe it's because we are.

This article basically boils down to "scientists suck, the government sucks, truck drivers have everything figured out". Pretty much the opposite of what you are suggesting. There's a layer of humility which obfuscates this a little.

Re: A truck driver uncovers secrets about the first nuclear bombs

#24

Post by CapitalistCartr »

amluto wrote: post #21
ChrisTheBore wrote: post #15

Earlier quoted context omitted.

>Does anyone understand what point is being made here? A cylindrical barrel is being fit over a fixed centre pin, rather than a pin inserted into a barrel. Makes sense when you realise that the moving component is inside of a similarly cylindrical bomb casing and that no fancy and complicated sabot and/or rail arrangement are required to keep it aligned and centered with the fixed pin. Most DC charging plugs work the…

I don't quite buy this reasoning. With a car charger, you indeed need to hold a fairly beefy contact in position so it mates with its counterpart. But in a car charger, there's no functional difference between the cable end and the car end -- sure, one is handheld and one is fixed to the car, but both ends need to secure their respective contacts. With the gun-type bomb, suppose the final critical assembly has a 2"-d…

The barrel is part of the casing, necessary for a sustained reaction.

Re: A truck driver uncovers secrets about the first nuclear bombs

#25

Post by erdos4d »

creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

I don't buy this at all. There is zero logic to firing the larger (female) piece onto the smaller (male) piece. It makes the bore of the barrel needed to actually do it larger, increasing the weight of the air-dropped weapon in the process. From a physics point of view, there is nothing to be gained either. Neither piece knows which got shot at who, and once piece geometry is set, all that is important is that the two pieces are brought together as fast as possible. That means the smaller (lighter) piece goes in the barrel.

Re: A truck driver uncovers secrets about the first nuclear bombs

#26

Post by ChuckMcM »

I got this guy's "book" off Amazon back when he was taking them to Kinko's to be printed up. His is a fairly remarkable story of curiosity which I have always enjoyed. He even signed it for me.

What is not often pointed out is that he managed to reason his way into understanding to various points, and the process of doing so revealed information that is otherwise still classified.

As a teen in Las Vegas in the 70's we could "feel" the underground tests, and I was always fascinated by the test site. I even managed to snag a summer internship there (inadvertently[1]) when I was in college.

I know folks who worked at Sandia and Lawrence Livermore who found the book fairly remarkable.

[1] The job offer was for the contractor facility in Las Vegas but my clearance had not come through so they bused me to an unclassified facility at the test site to do the work.

Re: A truck driver uncovers secrets about the first nuclear bombs

#27

Post by beerandt »

creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

One of the first "public" descriptions of this process was phrased something like:

"shooting a mass of uranium down a barrel into another mass of uranium to form a supercritical mass."

My guess is that the person who first said that didn't intend for the metaphor/description to be taken quite as literally as everyone ended up taking it. (Or they meant to mislead.)

Hypothetically, if you read "into" as crash/collision and not "in to"/inside of, you start to see how a generic description could be ambiguous. Run this (or a similar story) through a few iterations of the telephone game and draft revisions by journalists/editors (that somehow all seem to graduate without ever taking a single sophomore level technical writing course), and a description becomes a misunderstood metaphor becomes a fact. Somewhere along the way, the word "bullet" gets thrown in, and then no one "un-see" the visual.

That's my take. That and the author of tfa is trying way too hard to make a big a deal out of it being a "gendered" thing, when it's not.

Re: A truck driver uncovers secrets about the first nuclear bombs

#28

Post by [deleted] »

bouncycastle wrote: post #22
creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

Perhaps, since the larger piece would have more mass than the smaller, therefore it would impact with more force, and for a more sustained period, allowing it to reach criticality?

[deleted]

Re: A truck driver uncovers secrets about the first nuclear bombs

#29

Post by fermienrico »

beerandt wrote: post #27
creato wrote: post #12

> In the standard historical accounts, the way that the bomb’s gun mechanism worked was by shooting a cylindrical “male” uranium projectile into a concave, stationary uranium target. This act of atomic coitus created a mass sufficient to produce a critical reaction. The mass of the projectile was said to be 38.5 kilograms, and the mass of the target was said to be 25.6 kilograms. But no matter how many times Coster-M…

One of the first "public" descriptions of this process was phrased something like: "shooting a mass of uranium down a barrel into another mass of uranium to form a supercritical mass." My guess is that the person who first said that didn't intend for the metaphor/description to be taken quite as literally as everyone ended up taking it. (Or they meant to mislead.) Hypothetically, if you read "into" as crash/collision…

> My guess is that the person who first said that didn't intend for the metaphor/description to be taken quite as literally as everyone ended up taking it. (Or they meant to mislead.)

This is the problem. Why are they trying to shoehorn male or female dominance here? The whole thing is not only unpleasant to read, but also confusing.

Re: A truck driver uncovers secrets about the first nuclear bombs

#30

Post by amluto »

CapitalistCartr wrote: post #24
amluto wrote: post #21

Earlier quoted context omitted.

I don't quite buy this reasoning. With a car charger, you indeed need to hold a fairly beefy contact in position so it mates with its counterpart. But in a car charger, there's no functional difference between the cable end and the car end -- sure, one is handheld and one is fixed to the car, but both ends need to secure their respective contacts. With the gun-type bomb, suppose the final critical assembly has a 2"-d…

The barrel is part of the casing, necessary for a sustained reaction.

True, but does the barrel need to be a cylinder? That is, couldn’t the casing be a sphere with a hole cut out and a cylinder inserted? I suppose this could be much less pleasant to machine and to service.
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