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It always amazes me how seemingly careless they were with these nuclear devices back then. To know that such a devestating bomb was handled by a sultry, shirtle

It always amazes me how seemingly careless they were with these nuclear devices back then. To know that such a devestating bomb was handled by a sultry, shirtless youngster, in a shed on a small island in the Pacific... It reminds me of the Slotin Incident (http://www.damninteresting.com/bitten-by-the-nuclear-dragon/ http://www.damninteresting.com/bitten-by-the-nuclear-dragon/) where dr. Louis Slotin accidently slipped the screwdriver he used to separate two plutonium/uranium hemispheres: "Immediately, all eight scientists in the room felt a wave of heat accompanied by a blue glow as the plutonium sphere vomited an invisible burst of gamma and neutron radiation into the room. As the lab's Geiger counter clicked hysterically, Louis used his bare hand to push the upper plutonium hemisphere off and onto the floor, which terminated the supercritical reaction moments after it began." Big oopsie. However gruesome the goal of these bombs, the rate of advancement in such a short timespan is nothing short of amazing. From the very first successful test (Trinity) to bombing Hiroshima: just 21 days. They were great days for science, but a shame to mankind that it had to come this far.

cpwright 12y ago
Ignoring the nuclear device aspect of it, I would think that these days anyone spraying any kind of sealant or paint these days in a commercial setting would have PPE to avoid breathing the stuff in.
- junto 12y ago
  As well as the health and safety aspect I imagine that during times of war, your personal long term health outlook pales in comparison to the short-medium term survival possibilities. Hence, I imagine that many servicemen and women didn't see themselves as having a long life span. Maybe not consciously, but certainly subconsciously.
AJ007 12y ago
There have been a lot of very close calls. Including recently.
thefreeman 12y ago
That is amazing. I have had a lot of oh shit moments in my days, but none gets close to dropping the plutonium onto the uranium and nearly detonating a nuclear payload.
- dirktheman 12y ago
  Or accidently dropping a tungsten carbide brick on the plutonium bomb core, for that matter...(http://en.wikipedia.org/wiki/Harry_K._Daghlian,_Jr. http://en.wikipedia.org/wiki/Harry_K._Daghlian,_Jr.) That picture fascinates me. It's like a deadly game of Jenga.
- maaku 12y ago
  It wouldn't have detonated. The worst that would have happened... is exactly what did happen. Lots of radiation release and the death of one nuclear scientist that should have been more careful (he died of radiation sickness a few days later).
  - thefreeman 12y ago
    Yea, after reading the article fully I wish I could edit my comment a bit. It isn't really amazing when 3 people died because of it (2 other scientists apparently later died as well).
- lutusp 12y ago
  > I have had a lot of oh shit moments in my days, but none gets close to dropping the plutonium onto the uranium and nearly detonating a nuclear payload. Not possible for a plutonium device, and this is why the implosion method was so technically challenging. The plutonium must be transitioned from subcritical to supercritical very, very fast to achieve any significant nuclear energy release. In the final design, shaped plastic explosives, chosen for their very high velocities, were used to compress the plutonium from all directions simultaneously, very fast. Then, after the compression phase is complete, a carefully timed burst of neutrons triggers the nuclear fission event.
jnsaff2 12y ago
You should read Command and Control which is about the history of nuclear accidents and management in the US. Carelessness didn't go away for a long time, especially in the upper management. Very well written and interesting book. http://www.amazon.com/Command-Control-Eric-Schlosser-ebook/dp/B00CDBZ6NA/ http://www.amazon.com/Command-Control-Eric-Schlosser-ebook/d...
- dirktheman 12y ago
  Thanks! I loved Fast Food Nation, and wasn't aware he wrote a new book. This is right up my alley!
- Malic 12y ago
  To anyone that wants to read this book (and you should), be prepared to frequently hold one hand under your jaw - to prevent it from hitting the floor when it falls. And if cold-war nuclear lore is your thing, check out the photo gallery at http://atomic-annhilation.blogspot.com http://atomic-annhilation.blogspot.com
- pavel_lishin 12y ago
  Weird, says not currently available for purchase - I don't even have the option to add it to the wish list.
  - mrbill 12y ago
    Click one of the formats (Kindle, hardcover, etc) and you should be able to purchase then.
    - pavel_lishin 12y ago
      Ah, thank you!
- tedjdziuba 12y ago
  Also worthwhile is "Five Myths about Nuclear Weapons" http://www.amazon.com/Five-Myths-About-Nuclear-Weapons/dp/0544103254/ref=sr_1_1?ie=UTF8&qid=1412089930&sr=8-1&keywords=myths+about+nuclear+weapons http://www.amazon.com/Five-Myths-About-Nuclear-Weapons/dp/05... A very well-researched book that challenges, adequately in my opinion, some of the fundamental assumptions about nuclear weapons. First and foremost, that "the atomic bombs ended the war with Japan".
larrydag 12y ago
I'm no nuclear physicist but I think there wasn't a danger of dropping the a-bomb accidentally. If I recall from reading about it the a-bomb needed a huge electronic catalyst to start the fission processes. In fact a lot of time was spent setting up the timer to determine when to start the reaction during the bomb descent. I'm just recollecting so i could be wrong.
- dirktheman 12y ago
  You're right, there wasn't any immediate danger of fission. It's just that now we know how deadly and powerful these things were, it seems almost endearing to see them being handled this way.
  - maaku 12y ago
    Are they? These aren't the multi-megaton nuclear behemoths that people associate with nukes post-cold war. Those bombs are three orders of magnitude more powerful than the one shown in the picture. This bomb is probably comparable to a warehouse full of conventional weapons, which the shirtless youngster was probably manhandling in his everyday work. And unlike a conventional weapon, it's pretty hard for a nuke of this design to accidentally explode.
    - scarletham 12y ago
      They're still deadly, and as he said, it's simply endearing.
- codewritinfool 12y ago
  In reality, the early weapons were not "single-point safe". That means that should a single one of those shaped charges be fired via static electricity, etc., that there would be at the least severe contamination and quite likely somewhat of a yield.
- gambiting 12y ago
  The original nuclear bombs used hi voltage detonators, detonators which were incredibly highly sensitive - and they all had to be connected by hand just before the bomb was loaded. If you read the command&conquer book that was linked to above you will see that the risks that were being taken with early designs were just insane and it's incredible that we have not had an accidental detonation during the cold war.
mikeash 12y ago
I'm not sure the interval from test to drop is all that meaningful. If you can build one, you can build two. Also note that the design tested at Trinity was not the design used on Hiroshima. The Little Boy design used on Hiroshima was a gun-type design that was so obvious it would work that it wasn't felt that any testing was required. The Fat Man design used on Nagasaki was vastly more complex (but much more efficient and scalable) that it was felt best to validate it before using it in war. I occasionally wonder about the atomic bombings and the timing of everything. If the project had been delayed by a year or so, the war would have ended without them. But the development would continue, and the Cold War would no doubt kick off something like it did in reality. But without two examples of the horrors of nuclear war, would the superpowers have been as restrained as they were in reality? Rather than the first (and so far, only) use of nuclear weapons in war being two primitive bombs, it could have been hundreds or thousands, in a war run by people thinking that they were just doing a scaled up version of the city bombing of WWII. It seems like the timing ended up being extremely lucky.
- dirktheman 12y ago
  I'm not sure if I agree on the superpowers being as restrained as they were. The US and the USSR had over 70,000 nuclear warheads in the 80's... If they showed any restraint, it was more in not using them.
  - mikeash 12y ago
    That's what I mean by restraint. They built up a vast arsenal, but never used it. Imagine the alternate version of something like the Korean War in a world where WWII ended without the use of nuclear weapons. Are the Americans going to refrain from using nuclear weapons on their enemies when the going gets tough in that scenario? My money is on "no", and I'd also wager that the nuclear bombing campaign would last a lot longer, since it would be initiated against countries with a much greater capacity to fight. For example, Mao really didn't seem to care about the potential devastation of nuclear war: "Let us imagine how many people would die if war breaks out. There are 2.7 billion people in the world, and a third could be lost. If it is a little higher it could be half ... I say that if the worst came to the worst and one-half dies, there will still be one-half left, but imperialism would be razed to the ground and the whole world would become socialist. After a few years there would be 2.7 billion people again."
deleted 12y ago
[deleted]
hamiltonkibbe 12y ago
There were a few nearly identical incidents. Another involved someone working alone after hours dropping the last block of plutonium/uranium onto a stack during criticality testing after realizing that it was going to go critical, and removing it by hand. Its pretty amazing that the test procedure for determining the critical mass was essentially "stack these blocks of plutonium/uranium (by hand) until the neutron detector starts going off, and then take one away"
- ceejayoz 12y ago
  > There were a few nearly identical incidents. Another involved someone working alone after hours dropping the last block of plutonium/uranium onto a stack during criticality testing after realizing that it was going to go critical, and removing it by hand. IIRC, that incident happened with the same sphere of plutonium, causing it to be called the "Demon Core".
Involute 12y ago
The bomb that was tested during Trinity was a plutonium, implosion device, completely different from the uranium, gun-type device dropped on Hiroshima. The designers were so confident of the latter that it was never tested before being deployed.
- dragonwriter 12y ago
  As I underestand, it was not purely confidence, it was also that there was a major war going on and the expected production rate was low, so the risk of failure in the field was judged a lesser cost than the using up another bomb in testing.
  - maaku 12y ago
    It took basically the entire Manhattan project to create enough U-235 for that single bomb dropped on Hiroshima. There was no more U-235 coming, at least not any on a scale or timeline for the war. It probably would have been more efficient to dilute the U-235 into reactor grade and use it to manufacture weapons grade Plutonium. However at the time the U.S. only had two bombs (the ones dropped on Hiroshima and Nagasaki) and it was probably judged politically expedient to drop two instead of one.
    - knorby 12y ago
      Well, there were basically a few different strategies to produce U-235 during the war. For Hiroshima, most of the Uranium came from a very temporary but quicker to setup using an electromagnetic process at Y-12 in Oak Ridge, and that ended with the war. The gaseous diffusion plant at K-25, also in Oak Ridge, came online in 1945 and ended up being the main enricher for much of the cold war; it was a construction marvel, and the fact it was built in 2 years is still remarkable. The US definitely would have been ready to produce many more in not too long for the war had it been needed. All of these processes were brand new at the time and mostly untested. Plutonium enrichment at the Hanford site used a reactor design that was validated well into the construction of the site. The Manhattan project already had a lot of risks, and they weren't going to attempt chaining projects for something unproven. Real experiments came after the war.
tedjdziuba 12y ago
"The Making of the Atomic Bomb" http://www.amazon.com/Making-Atomic-Bomb-25th-Anniversary/dp/1451677618/ref=sr_1_1?ie=UTF8&qid=1412089532&sr=8-1&keywords=the+making+of+the+atomic+bomb http://www.amazon.com/Making-Atomic-Bomb-25th-Anniversary/dp... is a fantastic book for anybody in a technical field. It describes in precise detail how a team of scientists, materials engineers, and government came together to make possible something that started as theoretical physics. J. Robert Oppenheimer and Leslie Groves were a fascinating team, Oppenheimer being a physicist and Groves an Army general. A must for anyone in technical management.
- lobster_johnson 12y ago
  Its sequel, Dark Sun: The Making of the Hydrogen Bomb [1] is also great. It deals with Edward Teller's hydrogen bomb, the nuclear spies (Fuchs, the Rosenbergs, etc.), the beginning of the cold war, Oppenheimer's ambitious attempts at atomic regulation, and his subsequent trial. TMAB stands out, however; it is superb in its panoramic, often lyrical depiction of science and philosophy coming together in a broad cast of scientists. Much of Dark Sun is about spies, cops and military figures, and its subject matter is somewhat more prosaic. [1] http://www.amazon.com/Dark-Sun-Making-Hydrogen-Bomb/dp/0684824140 http://www.amazon.com/Dark-Sun-Making-Hydrogen-Bomb/dp/06848...
shangxiao 12y ago
> "Immediately, all eight scientists in the room felt a wave of heat accompanied by a blue glow as the plutonium sphere vomited an invisible burst of gamma and neutron radiation into the room. As the lab's Geiger counter clicked hysterically, Louis used his bare hand to push the upper plutonium hemisphere off and onto the floor, which terminated the supercritical reaction moments after it began." Nit pick: What you have described is the incorrect version in the movie "Fat Man and Little Boy". It was a knee-jerk reaction that stopped the supercritical reaction, and it was the beryllium outer sphere which was dropped, not the plutonium core. Slotin was holding the top half of the beryllium sphere with his thumb which he immediately lifted up due to the intense heat.
- eltoozero 12y ago
  > which he immediately lifted up due to the intense heat. Had he not made this instinctive move, everyone present would have perished and the area would have remained deadly until some other poor soul came upon the tragedy to stop the reaction. The first-hand accounts of those present are in the thorough official report, which just happens to be collected in John Coster-Mullen's Atom Bombs book.
  - gambiting 12y ago
    There was a similar thing somewhere in Russia, I just can't find the link right now....when a scientist spilled some radioactive material, ran out, and then out of fear of prosecution came back to clean it up - died of radiation poisoning shortly after. Anyone remembers which accident was it?
theoh 12y ago
It is not clear that dropping the bomb was necessary to end the war. Was it even necessary to develop it? Eisenhower said "it wasn't necessary to hit them with that awful thing." At the time Truman said Japan had been "repaid many fold" for Pearl Harbor. In these new images there is a bit of graffiti on the bomb allegedly written by a Rear Admiral: "a second kiss for Hirohito". It seems to me like the mood in the US camp was "let's hit them hard, teach them a lesson." rather than a more considered or balanced calculation. Edit: in the documentary "The Fog of War" on McNamara, there is discussion of Curtis LeMay's decision to firebomb Tokyo. In that case there was apparently a degree of cool-headed calculation. http://www.errolmorris.com/film/fow_transcript.html http://www.errolmorris.com/film/fow_transcript.html Some discussion of the nuclear bomb decision here: http://www.washingtonexaminer.com/it-wasnt-necessary-to-hit-them-with-that-awful-thing-why-dropping-the-a-bombs-was-wrong/article/2534018 http://www.washingtonexaminer.com/it-wasnt-necessary-to-hit-... (I have no idea what the politics of that paper are, caveat lector)
- Tombone5 12y ago
  "The use of the atomic bomb would have to be done with visual targeting, not by use of radar. [...] The targets should be 'large urban areas of not less than 3 miles in diameter existing in the larger populated areas… between the Japanese cities of Tokyo and Nagasaki… [and] should have high strategic value.' A list of possible targets that met this criteria was given [...] Of these, Hiroshima was noted as 'the largest untouched target not on the 21st Bomber Command priority list.' Tokyo, on the other hand, was 'now practically all bombed and burned out and is practically rubble with only the palace grounds left standing.' It was further noted that they had to take into account that the policy of the 20th Air Force was now 'systematically bombing out' cities 'with the prime purpose in mind of not leaving one stone lying on the other,' and that they would not likely reserve targets just for the Manhattan Project." "Stimson left the meeting thinking Truman completely understood the matter, and the final target order — with Hiroshima, Kokura, Niigata, and Nagasaki (the latter added only then) — was sent out. But what did Truman take away from this meeting? We can look at Truman’s own diary entry from July 25th: " This weapon is to be used against Japan between now and August 10th. I have told the Sec. of War, Mr. Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop that terrible bomb on the old capital or the new. He and I are in accord. The target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives. I’m sure they will not do that, but we will have given them the chance. It is certainly a good thing for the world that Hitler’s crowd or Stalin’s did not discover this atomic bomb. It seems to be the most terrible thing ever discovered, but it can be made the most useful. " This passage reflects an incredible misconception. Truman appears, here, to believe that Hiroshima was 'a purely military' target, and that 'soldiers and sailors' would be killed, 'not women and children.' But of course every city on that list was inhabited primarily by civilians. And by the calculus of war being waged, every city on that list had a military connection — they produced weapons for the military." http://blog.nuclearsecrecy.com/2014/08/08/kyoto-misconception/ http://blog.nuclearsecrecy.com/2014/08/08/kyoto-misconceptio...
leef 12y ago
Back then? We haven't gotten all that much better according to John Oliver (http://www.youtube.com/watch?v=1Y1ya-yF35g http://www.youtube.com/watch?v=1Y1ya-yF35g)
MrZongle2 12y ago
To know that such a devestating bomb was handled by a sultry, shirtless youngster, in a shed on a small island in the Pacific... Consider this: even if that "youngster" wasn't filtered out from his contemporaries due to his skills or character, he still came from a generation that was engaged in a war that had taken the lives of friends, family and neighbors. It was also probably also obvious by then that you don't mess around with bombs, regardless of how they worked. I'd wager that the average "youngster" during WW2 was a great deal more responsible than their modern-day counterparts of similar age.
samplonius 12y ago
So if the airmen wore shirts and were less sexy, you'd feel the whole situation was more safe? Or, do you need to take a time out and have a cold shower? Because it kinda of sounds like you are one Tom of Finland book away from hyperventilating. This sort of appeal to superficial appearances generally doesn't hunt on HackerNews.

cpwright 12y ago

Ignoring the nuclear device aspect of it, I would think that these days anyone spraying any kind of sealant or paint these days in a commercial setting would have PPE to avoid breathing the stuff in.

junto 12y ago
As well as the health and safety aspect I imagine that during times of war, your personal long term health outlook pales in comparison to the short-medium term survival possibilities. Hence, I imagine that many servicemen and women didn't see themselves as having a long life span. Maybe not consciously, but certainly subconsciously.

AJ007 12y ago

There have been a lot of very close calls. Including recently.

thefreeman 12y ago

That is amazing. I have had a lot of oh shit moments in my days, but none gets close to dropping the plutonium onto the uranium and nearly detonating a nuclear payload.

dirktheman 12y ago
Or accidently dropping a tungsten carbide brick on the plutonium bomb core, for that matter...(http://en.wikipedia.org/wiki/Harry_K._Daghlian,_Jr. http://en.wikipedia.org/wiki/Harry_K._Daghlian,_Jr.) That picture fascinates me. It's like a deadly game of Jenga.
maaku 12y ago
It wouldn't have detonated. The worst that would have happened... is exactly what did happen. Lots of radiation release and the death of one nuclear scientist that should have been more careful (he died of radiation sickness a few days later).
- thefreeman 12y ago
  Yea, after reading the article fully I wish I could edit my comment a bit. It isn't really amazing when 3 people died because of it (2 other scientists apparently later died as well).
lutusp 12y ago
> I have had a lot of oh shit moments in my days, but none gets close to dropping the plutonium onto the uranium and nearly detonating a nuclear payload. Not possible for a plutonium device, and this is why the implosion method was so technically challenging. The plutonium must be transitioned from subcritical to supercritical very, very fast to achieve any significant nuclear energy release. In the final design, shaped plastic explosives, chosen for their very high velocities, were used to compress the plutonium from all directions simultaneously, very fast. Then, after the compression phase is complete, a carefully timed burst of neutrons triggers the nuclear fission event.

jnsaff2 12y ago

You should read Command and Control which is about the history of nuclear accidents and management in the US. Carelessness didn't go away for a long time, especially in the upper management. Very well written and interesting book. http://www.amazon.com/Command-Control-Eric-Schlosser-ebook/dp/B00CDBZ6NA/ http://www.amazon.com/Command-Control-Eric-Schlosser-ebook/d...

dirktheman 12y ago
Thanks! I loved Fast Food Nation, and wasn't aware he wrote a new book. This is right up my alley!
Malic 12y ago
To anyone that wants to read this book (and you should), be prepared to frequently hold one hand under your jaw - to prevent it from hitting the floor when it falls. And if cold-war nuclear lore is your thing, check out the photo gallery at http://atomic-annhilation.blogspot.com http://atomic-annhilation.blogspot.com
pavel_lishin 12y ago
Weird, says not currently available for purchase - I don't even have the option to add it to the wish list.
- mrbill 12y ago
  Click one of the formats (Kindle, hardcover, etc) and you should be able to purchase then.
  - pavel_lishin 12y ago
    Ah, thank you!
tedjdziuba 12y ago
Also worthwhile is "Five Myths about Nuclear Weapons" http://www.amazon.com/Five-Myths-About-Nuclear-Weapons/dp/0544103254/ref=sr_1_1?ie=UTF8&qid=1412089930&sr=8-1&keywords=myths+about+nuclear+weapons http://www.amazon.com/Five-Myths-About-Nuclear-Weapons/dp/05... A very well-researched book that challenges, adequately in my opinion, some of the fundamental assumptions about nuclear weapons. First and foremost, that "the atomic bombs ended the war with Japan".

larrydag 12y ago

I'm no nuclear physicist but I think there wasn't a danger of dropping the a-bomb accidentally. If I recall from reading about it the a-bomb needed a huge electronic catalyst to start the fission processes. In fact a lot of time was spent setting up the timer to determine when to start the reaction during the bomb descent. I'm just recollecting so i could be wrong.

dirktheman 12y ago
You're right, there wasn't any immediate danger of fission. It's just that now we know how deadly and powerful these things were, it seems almost endearing to see them being handled this way.
- maaku 12y ago
  Are they? These aren't the multi-megaton nuclear behemoths that people associate with nukes post-cold war. Those bombs are three orders of magnitude more powerful than the one shown in the picture. This bomb is probably comparable to a warehouse full of conventional weapons, which the shirtless youngster was probably manhandling in his everyday work. And unlike a conventional weapon, it's pretty hard for a nuke of this design to accidentally explode.
  - scarletham 12y ago
    They're still deadly, and as he said, it's simply endearing.
codewritinfool 12y ago
In reality, the early weapons were not "single-point safe". That means that should a single one of those shaped charges be fired via static electricity, etc., that there would be at the least severe contamination and quite likely somewhat of a yield.
gambiting 12y ago
The original nuclear bombs used hi voltage detonators, detonators which were incredibly highly sensitive - and they all had to be connected by hand just before the bomb was loaded. If you read the command&conquer book that was linked to above you will see that the risks that were being taken with early designs were just insane and it's incredible that we have not had an accidental detonation during the cold war.

mikeash 12y ago

I'm not sure the interval from test to drop is all that meaningful. If you can build one, you can build two. Also note that the design tested at Trinity was not the design used on Hiroshima. The Little Boy design used on Hiroshima was a gun-type design that was so obvious it would work that it wasn't felt that any testing was required. The Fat Man design used on Nagasaki was vastly more complex (but much more efficient and scalable) that it was felt best to validate it before using it in war. I occasionally wonder about the atomic bombings and the timing of everything. If the project had been delayed by a year or so, the war would have ended without them. But the development would continue, and the Cold War would no doubt kick off something like it did in reality. But without two examples of the horrors of nuclear war, would the superpowers have been as restrained as they were in reality? Rather than the first (and so far, only) use of nuclear weapons in war being two primitive bombs, it could have been hundreds or thousands, in a war run by people thinking that they were just doing a scaled up version of the city bombing of WWII. It seems like the timing ended up being extremely lucky.

dirktheman 12y ago
I'm not sure if I agree on the superpowers being as restrained as they were. The US and the USSR had over 70,000 nuclear warheads in the 80's... If they showed any restraint, it was more in not using them.
- mikeash 12y ago
  That's what I mean by restraint. They built up a vast arsenal, but never used it. Imagine the alternate version of something like the Korean War in a world where WWII ended without the use of nuclear weapons. Are the Americans going to refrain from using nuclear weapons on their enemies when the going gets tough in that scenario? My money is on "no", and I'd also wager that the nuclear bombing campaign would last a lot longer, since it would be initiated against countries with a much greater capacity to fight. For example, Mao really didn't seem to care about the potential devastation of nuclear war: "Let us imagine how many people would die if war breaks out. There are 2.7 billion people in the world, and a third could be lost. If it is a little higher it could be half ... I say that if the worst came to the worst and one-half dies, there will still be one-half left, but imperialism would be razed to the ground and the whole world would become socialist. After a few years there would be 2.7 billion people again."

deleted 12y ago

[deleted]

hamiltonkibbe 12y ago

There were a few nearly identical incidents. Another involved someone working alone after hours dropping the last block of plutonium/uranium onto a stack during criticality testing after realizing that it was going to go critical, and removing it by hand. Its pretty amazing that the test procedure for determining the critical mass was essentially "stack these blocks of plutonium/uranium (by hand) until the neutron detector starts going off, and then take one away"

ceejayoz 12y ago
> There were a few nearly identical incidents. Another involved someone working alone after hours dropping the last block of plutonium/uranium onto a stack during criticality testing after realizing that it was going to go critical, and removing it by hand. IIRC, that incident happened with the same sphere of plutonium, causing it to be called the "Demon Core".

Involute 12y ago

The bomb that was tested during Trinity was a plutonium, implosion device, completely different from the uranium, gun-type device dropped on Hiroshima. The designers were so confident of the latter that it was never tested before being deployed.

dragonwriter 12y ago
As I underestand, it was not purely confidence, it was also that there was a major war going on and the expected production rate was low, so the risk of failure in the field was judged a lesser cost than the using up another bomb in testing.
- maaku 12y ago
  It took basically the entire Manhattan project to create enough U-235 for that single bomb dropped on Hiroshima. There was no more U-235 coming, at least not any on a scale or timeline for the war. It probably would have been more efficient to dilute the U-235 into reactor grade and use it to manufacture weapons grade Plutonium. However at the time the U.S. only had two bombs (the ones dropped on Hiroshima and Nagasaki) and it was probably judged politically expedient to drop two instead of one.
  - knorby 12y ago
    Well, there were basically a few different strategies to produce U-235 during the war. For Hiroshima, most of the Uranium came from a very temporary but quicker to setup using an electromagnetic process at Y-12 in Oak Ridge, and that ended with the war. The gaseous diffusion plant at K-25, also in Oak Ridge, came online in 1945 and ended up being the main enricher for much of the cold war; it was a construction marvel, and the fact it was built in 2 years is still remarkable. The US definitely would have been ready to produce many more in not too long for the war had it been needed. All of these processes were brand new at the time and mostly untested. Plutonium enrichment at the Hanford site used a reactor design that was validated well into the construction of the site. The Manhattan project already had a lot of risks, and they weren't going to attempt chaining projects for something unproven. Real experiments came after the war.

tedjdziuba 12y ago

"The Making of the Atomic Bomb" http://www.amazon.com/Making-Atomic-Bomb-25th-Anniversary/dp/1451677618/ref=sr_1_1?ie=UTF8&qid=1412089532&sr=8-1&keywords=the+making+of+the+atomic+bomb http://www.amazon.com/Making-Atomic-Bomb-25th-Anniversary/dp... is a fantastic book for anybody in a technical field. It describes in precise detail how a team of scientists, materials engineers, and government came together to make possible something that started as theoretical physics. J. Robert Oppenheimer and Leslie Groves were a fascinating team, Oppenheimer being a physicist and Groves an Army general. A must for anyone in technical management.

lobster_johnson 12y ago
Its sequel, Dark Sun: The Making of the Hydrogen Bomb [1] is also great. It deals with Edward Teller's hydrogen bomb, the nuclear spies (Fuchs, the Rosenbergs, etc.), the beginning of the cold war, Oppenheimer's ambitious attempts at atomic regulation, and his subsequent trial. TMAB stands out, however; it is superb in its panoramic, often lyrical depiction of science and philosophy coming together in a broad cast of scientists. Much of Dark Sun is about spies, cops and military figures, and its subject matter is somewhat more prosaic. [1] http://www.amazon.com/Dark-Sun-Making-Hydrogen-Bomb/dp/0684824140 http://www.amazon.com/Dark-Sun-Making-Hydrogen-Bomb/dp/06848...

shangxiao 12y ago

> "Immediately, all eight scientists in the room felt a wave of heat accompanied by a blue glow as the plutonium sphere vomited an invisible burst of gamma and neutron radiation into the room. As the lab's Geiger counter clicked hysterically, Louis used his bare hand to push the upper plutonium hemisphere off and onto the floor, which terminated the supercritical reaction moments after it began." Nit pick: What you have described is the incorrect version in the movie "Fat Man and Little Boy". It was a knee-jerk reaction that stopped the supercritical reaction, and it was the beryllium outer sphere which was dropped, not the plutonium core. Slotin was holding the top half of the beryllium sphere with his thumb which he immediately lifted up due to the intense heat.

eltoozero 12y ago
> which he immediately lifted up due to the intense heat. Had he not made this instinctive move, everyone present would have perished and the area would have remained deadly until some other poor soul came upon the tragedy to stop the reaction. The first-hand accounts of those present are in the thorough official report, which just happens to be collected in John Coster-Mullen's Atom Bombs book.
- gambiting 12y ago
  There was a similar thing somewhere in Russia, I just can't find the link right now....when a scientist spilled some radioactive material, ran out, and then out of fear of prosecution came back to clean it up - died of radiation poisoning shortly after. Anyone remembers which accident was it?

theoh 12y ago

It is not clear that dropping the bomb was necessary to end the war. Was it even necessary to develop it? Eisenhower said "it wasn't necessary to hit them with that awful thing." At the time Truman said Japan had been "repaid many fold" for Pearl Harbor. In these new images there is a bit of graffiti on the bomb allegedly written by a Rear Admiral: "a second kiss for Hirohito". It seems to me like the mood in the US camp was "let's hit them hard, teach them a lesson." rather than a more considered or balanced calculation. Edit: in the documentary "The Fog of War" on McNamara, there is discussion of Curtis LeMay's decision to firebomb Tokyo. In that case there was apparently a degree of cool-headed calculation. http://www.errolmorris.com/film/fow_transcript.html http://www.errolmorris.com/film/fow_transcript.html Some discussion of the nuclear bomb decision here: http://www.washingtonexaminer.com/it-wasnt-necessary-to-hit-them-with-that-awful-thing-why-dropping-the-a-bombs-was-wrong/article/2534018 http://www.washingtonexaminer.com/it-wasnt-necessary-to-hit-... (I have no idea what the politics of that paper are, caveat lector)

Tombone5 12y ago
"The use of the atomic bomb would have to be done with visual targeting, not by use of radar. [...] The targets should be 'large urban areas of not less than 3 miles in diameter existing in the larger populated areas… between the Japanese cities of Tokyo and Nagasaki… [and] should have high strategic value.' A list of possible targets that met this criteria was given [...] Of these, Hiroshima was noted as 'the largest untouched target not on the 21st Bomber Command priority list.' Tokyo, on the other hand, was 'now practically all bombed and burned out and is practically rubble with only the palace grounds left standing.' It was further noted that they had to take into account that the policy of the 20th Air Force was now 'systematically bombing out' cities 'with the prime purpose in mind of not leaving one stone lying on the other,' and that they would not likely reserve targets just for the Manhattan Project." "Stimson left the meeting thinking Truman completely understood the matter, and the final target order — with Hiroshima, Kokura, Niigata, and Nagasaki (the latter added only then) — was sent out. But what did Truman take away from this meeting? We can look at Truman’s own diary entry from July 25th: " This weapon is to be used against Japan between now and August 10th. I have told the Sec. of War, Mr. Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop that terrible bomb on the old capital or the new. He and I are in accord. The target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives. I’m sure they will not do that, but we will have given them the chance. It is certainly a good thing for the world that Hitler’s crowd or Stalin’s did not discover this atomic bomb. It seems to be the most terrible thing ever discovered, but it can be made the most useful. " This passage reflects an incredible misconception. Truman appears, here, to believe that Hiroshima was 'a purely military' target, and that 'soldiers and sailors' would be killed, 'not women and children.' But of course every city on that list was inhabited primarily by civilians. And by the calculus of war being waged, every city on that list had a military connection — they produced weapons for the military." http://blog.nuclearsecrecy.com/2014/08/08/kyoto-misconception/ http://blog.nuclearsecrecy.com/2014/08/08/kyoto-misconceptio...

leef 12y ago

Back then? We haven't gotten all that much better according to John Oliver (http://www.youtube.com/watch?v=1Y1ya-yF35g http://www.youtube.com/watch?v=1Y1ya-yF35g)

MrZongle2 12y ago

To know that such a devestating bomb was handled by a sultry, shirtless youngster, in a shed on a small island in the Pacific... Consider this: even if that "youngster" wasn't filtered out from his contemporaries due to his skills or character, he still came from a generation that was engaged in a war that had taken the lives of friends, family and neighbors. It was also probably also obvious by then that you don't mess around with bombs, regardless of how they worked. I'd wager that the average "youngster" during WW2 was a great deal more responsible than their modern-day counterparts of similar age.

samplonius 12y ago

So if the airmen wore shirts and were less sexy, you'd feel the whole situation was more safe? Or, do you need to take a time out and have a cold shower? Because it kinda of sounds like you are one Tom of Finland book away from hyperventilating. This sort of appeal to superficial appearances generally doesn't hunt on HackerNews.