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Lost Images from the 1945 Trinity Nuclear Test Restored

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Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#101

Post by fluidcruft »

gpm wrote: post #78
libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

> Or it might have ignited a fusion reaction in the atmosphere and destroyed the world Someone's got to explain to me how this was even remotely plausible. We've had orders of magnitude more energetic events in earth's history that they would be aware of (dinosaur slaying asteroid for instance). These didn't manage to destroy the earth by turning the atmosphere into a fusion reactor. Surely they were aware of this. S…

Dinosaur-slaying asteroid theory comes from 1980s so it probably wouldn't have crossed their minds.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#102

Post by fragmede »

ghaff wrote: post #73
libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

It was probably all pretty silly but there were a few probably-not-all-nutcases that were concerned about the LHC causing something horrible.

I dunno, ever since that weasel got stuck in it in 2016, things haven't been super great.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#103

Post by jstummbillig »

libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

Increasingly with more powerful and precise technology the relative danger of the bomb will decrease, to the point where the bombs will become meaningless. The stigma is too big, the blowback is too severe and we have countless other ways to pummel each other into oblivion with more finesse.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#104

Post by contubernio »

libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

My grandfather was a student of Kistiakowksy and worked on the simultaneity part of the firing unit and was present at the assembly of the bomb and to watch the detonation. He recounted being quite nervous that his contribution would fail (as it had a short while before the final test) and the test would be a dud, but no one involved seriously in the scientific and engineering part of the building of the bomb had serious doubts that it would work once the technical issues were overcome, and none of them worried that it would ignite the atmosphere, because they knew enough to know that was silly. They'd all been working on this and doing thousands (!) of tests for months or years at that point. During the test he was given what he called the "chicken switch" that could abort the test at the last moment, and he always said that his biggest worry had been that he would stupidly abort the test in a moment of panic (surely this was exactly why he was given the switch). He described the actual explosion as the most beautiful thing he saw in his life.

When one looks at the history one needs to remember that these were scientists and engineers who behaved as such. My grandfather, for example, was the sort of person who always loved blowing things up. He'd nearly blown up the family home as a kid when given a chemistry set ... and he studied chemistry because he liked blowing things up ... and he wrote a PhD thesis about the shock waves generated by blowing up a really big (conventional) bomb. It all gets dressed up as studying shock waves and so forth, but it's really kids blowing things up. They get caught up in the challenge of it. The consequences, political, moral and otherwise, are not forefront in the thinking of most. None of them are innocent, but some have misgivings or second thoughts. Others are more cynical and ambitious and even sinister. There are Oppenheimers and there are Tellers.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#105

Post by jeremyjh »

gpm wrote: post #78
libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

> Or it might have ignited a fusion reaction in the atmosphere and destroyed the world Someone's got to explain to me how this was even remotely plausible. We've had orders of magnitude more energetic events in earth's history that they would be aware of (dinosaur slaying asteroid for instance). These didn't manage to destroy the earth by turning the atmosphere into a fusion reactor. Surely they were aware of this. S…

> Someone's got to explain to me how this was even remotely plausible.

You need to understand what a nuclear chain reaction is. https://en.wikipedia.org/wiki/Nuclear_chain_reaction

> We've had orders of magnitude more energetic events in earth's history

It isn't about energy. There was never an unbounded nuclear chain reaction of anywhere near this magnitude on the planet before Trinity. A large asteroid impact doesn't cause a nuclear chain reaction at all. The moon impact melted the entire crust but didn't cause a nuclear chain reaction.

In fact, the only chain reaction that happened at all before Fermi's experiment in 1942 - that we know of - was in Oklo (now Gabon) about 1.8 billion years ago. We didn't learn about that until 1972, and anyway that was more like a controlled reactor pile and it only happened because there was so much more Uranium 235 so early in the Earth's history.

The event at Trinity was completely different because so many neutrons were released at exactly the same instant. They had good reasons to be very confident in their models and calculations, but they were not 100% sure, and as TFA points out, the blast was several times more powerful than most models predicted.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#106

Post by reedf1 »

contubernio wrote: post #104
libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

My grandfather was a student of Kistiakowksy and worked on the simultaneity part of the firing unit and was present at the assembly of the bomb and to watch the detonation. He recounted being quite nervous that his contribution would fail (as it had a short while before the final test) and the test would be a dud, but no one involved seriously in the scientific and engineering part of the building of the bomb had ser…

This very much overstates the certainty of the scientists in the outcome of the explosion. They could be pretty certain it would work - but they were not at all certain about the result of producing energy, pressures, temperature and forces that have never been tested on earthly reality before. There were many unexcepted outcomes of the explosion, we are just lucky (as we usually are with new science) that they weren't particularly bad.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#107

Post by u8080 »

iamjs wrote: post #100
jltsiren wrote: post #72

Earlier quoted context omitted.

I remember similar warnings from when I visited Chernobyl ~20 years ago. The ambient radiation exposure was not that different from the average flight, but there could be some actual risks if you accidentally ingest radioactive dust.

I know the Chernobyl fallout had a pretty significant impact on agricultural in the region, but I don't think I've ever heard about anything similar in New Mexico, Texas, Oklahoma, or Colorado. Why not? Surely there is less agricultural activity on the American West than in Eastern Europe, but is that the only reason?

You could check present Cesium-137 levels in mushrooms or forest berries with pretty simple tools to track that btw.

In Russia we used blueberries from certain region(they were openly sold on marketplaces) to calibrate amateur spectrometers(like RadiaCode 101).

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#108

Post by ndc »

butlike wrote: post #46
cassianoleal wrote: post #5

> And physicist George Kistiakowsky found himself certain that “at the end of the world—in the last millisecond of the Earth’s existence—the last human will see what we saw.” I highly doubt it. The last human will likely live many years in agony, fighting disease and starvation.

I doubt it. I've ruminated a little on this and what I think is that as people start dying off, the survivors will find a rather pleasant existence before the end. People start dying off, and all of a sudden housing prices go down. There's more parks open. The air feels fresher gradually. It's a gradual decline as human influence tapers off near the end. I think it will be more "The Last of Us" than "Mad Max"

Housing price goes down, but there's no maintenance. No shops open nearby, no hospitals, no firemen, no police, no gas stations.

People will flock to cities that still have services. Then the cities will have the same population density as before.

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#109

Post by leonidasrup »

libraryofbabel wrote: post #36

I used to teach a class on the history of contemporary science (WW2-present) and I started the class with Trinity. There’s no other moment better. We know how it turned out, but the people there waiting for the test did not know how it would turn out. The bomb might not have worked. Or it might have ignited a fusion reaction in the atmosphere and destroyed the world. Hans Bethe had sat down and done the calculations…

> Or it might have ignited a fusion reaction in the atmosphere and destroyed the world

"The “near zero” chances Oppenheimer unnerves Groves with in-movie probably come from Manhattan Project physicist Arthur Compton, who told author Pearl S. Buck in a 1959 interview that they’d calculated the odds at “slightly less than one-in-three-million.” In 1975, Bethe denied that there had ever been a less-than-one-in-three-million chance of setting the atmosphere on fire, but the idea had already lodged itself in the public imagination."

https://www.inverse.com/science/did-oppenheimer-really-worry...

Re: Lost Images from the 1945 Trinity Nuclear Test Restored

#110

Post by rpastuszak »

nateburke wrote: post #8
rpastuszak wrote: post #6

Earlier quoted context omitted.

I’m of a similar opinion, Lynch created a better depiction of it in twin peaks season 3.

Penderecki did most of the heavy lifting there

Ha, my almost neighbour from Kraków (from the times I still lived there)!
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