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Scene report from the Chernobyl Zone

moxie.org

221–230 of 264 posts

Re: Scene report from the Chernobyl Zone

#222
post #196

Earlier quoted context omitted.

The largest ever fission explosion was, IIRC, something like a few hundred kT. It's just physically impossible to have a bigger yield from fission alone, as the bomb assembly blows apart before it has time to fission. And this was from a carefully designed weapon, not a reactor fueled with LEU melting. So yes, 5 MT is pure fantasy with absolutely no connection to reality. As for prompt criticality, in a weapon the ne…

The largest fission device tested was the 720Kt UK Orange Herald: https://en.wikipedia.org/wiki/Orange_Herald

As Wikipedia says, that was a boosted fission device, not pure fission.

Re: Scene report from the Chernobyl Zone

#223
post #138

Earlier quoted context omitted.

Nothing against Moxie, but this stated fact is clearly nonsense. It certainly would have been terrible for a large volume of water to reach the burning core, but you're not going to get a 5MT blast from a reactor accident. It takes a LOT of things working perfectly to make a nuclear bomb explode correctly. Lots of bad things happen when reactors go critical, a nuclear blast is generally not one of them. It's the spre…

"Only 1400 kilograms of uranium and graphite mixture would have needed to hit the water to set off a new explosion. Our experts studied the possibility and concluded that the explosion would have had a force of 3 to 5 megatons. Minsk...would have been razed." - Vassili Nesterenko, director of the Institute of Nuclear Energy at the National Academy of Sciences of Belarus. I am not a nuclear physicist, but at least som…

Ignoring the plausibility of the yield, Minsk is over 150km away from Pripyat. It's impossible for a 5Mt explosion centered on Pripyat to even reach Minsk, let alone "raze" it.

Re: Scene report from the Chernobyl Zone

#224
post #222

Earlier quoted context omitted.

The largest fission device tested was the 720Kt UK Orange Herald: https://en.wikipedia.org/wiki/Orange_Herald

As Wikipedia says, that was a boosted fission device, not pure fission.

I should probably have said "single stage" rather than fission!

Re: Scene report from the Chernobyl Zone

#225
post #152

Earlier quoted context omitted.

In the end the atomic bombs weren't really any different than the other tools of total war though, like all the aforementioned fire bombings. There's a lot of reasons the Japanese capitulated, and the relentless damage being inflicted across the entire country by the US (including the atomic bombings) was a very important reason. If the US had just backed off and stopped applying pressure on Japan, the war may never…

> at least not on the terms that we were demanding (and got) Terms that were un-necessary. Japan still has an emperor no? Could have ended the war much earlier if they wanted to.

Emperor yes, military no. What's the point?

Re: Scene report from the Chernobyl Zone

#226
post #212

Earlier quoted context omitted.

> there is no study that links low level ionizing radiation to any harmful effect on humans This does not mean much. The direct destruction effect of strong radiation on cells is cumulative, the longer you're exposed, the greater harm done. Given the physics and biology knowledge, our best bet so far is that effect of weak but extraordinary radiation is cumulative as well. It will increase probability of cancer and l…

> This does not mean much. It does in the context of places, like those mentioned above, with naturally elevated levels of background radiation. The absence of studies out of these areas with links to harmful health effects is evidence that such levels are likely safe.

Again, absence of evidence does not mean much. Nobody is expecting the workers to fall down after minutes of work there, the effects of low level radiation are subtle but given the known mechanism or damage there is no basis for calling such levels safe. Workers working with radioactive tailings may suffer harmful long-term effects. But it is hard to causally connect old age health issues with presence in these areas decades ago. You cannot conclude "likely safe" from absence of information or because the workers seem fine. You would have to do the studies, which as you say, probably were not made.

Re: Scene report from the Chernobyl Zone

#227

Earlier quoted context omitted.

Even if a thousands died from Chernobyl, it reflects the danger of the Soviet system, not of nuclear energy. Just take the thing we learned in this week's episode: The design flaw on the RBMK reactors that caused the explosion had been observed before, but the report was classified to not put the glorious Soviet nuclear technology in a bad light !!! In any remotely sane system, security risks are published and compen…

I kinda miss your point. What then does the Fukushima incident reflect? Danger of Japanese system, lol? Or as the US contractors built it, the US system? As according analysis [1] the Fukushima station design itself did not consider the natural features of place. Chernobyl incident happened due to human error, according to same source. [1] https://en.wikipedia.org/wiki/Comparison_of_Fukushima_and_Ch... edit: formatti…

Fukushima was a very extreme natural disaster striking at a precise location to expose that the Fukushima reactors were not fully ready for a theoretically possible but never in 1000+ years of Japanese history observed earthquake.

15,897 people died in Japan that day, in buildings, roads, and vehicles. None from the nuclear incident. Yet no one talks about how the building, road, and vehicle security failed and wants to ban those.

Sure, the Fukushima security could and should have been better. The industry has learned the lessons, as it does from all accidents. But even if it didn't, we could easily absorb accidents like these for once in a 1000+ years and still be the cleanest energy form there is.

The comparison with Chernobyl is no comparison. That was an unforced error on a calm spring night. Operators doing experiments on badly designed reactors with known flaws they were not informed about because it would look bad to spread the information that pressing a certain button in a certain situation was risky. So they pressed the button, and the reactor exploded.

https://en.wikipedia.org/wiki/2011_T%C5%8Dhoku_earthquake_an...

Re: Scene report from the Chernobyl Zone

#228
"When that material then started to smolder downwards out through the floor of the chamber, it threatened to come into contact with a large amount of water that had pooled there as a result of early firefighter attempts to put it out with hoses. This would have ignited a second reaction that would have been the equivalent of a 5 megaton explosion. It would have leveled Kiev and Minsk, and would have ejected the nuclear material from the other 3 Chernobyl reactors with a force that would have rendered much of Europe uninhabitable for hundreds of years. With only days to stop it, Alexei Ananenko, Valeri Bezpalov, and Boris Baranov went into the ruins of the plant, knowingly facing almost certain death from that level of radiation exposure, to release valves that would drain 5 million gallons of water."

Is this really true? Are there better sources than this blog post?

Re: Scene report from the Chernobyl Zone

#229

Earlier quoted context omitted.

It's hard to say with certainty. It's not like we can re-run history and try it again. Japan certainly turned out well with what did happen; it's not clear that a better outcome would have resulted from a less total surrender on their part. There's a lot of value in helping to move forward when you admit that you were completely beaten, not just mostly beaten; the latter leaves the door open for a repeat. And another…

> They started the war, killed millions of people in the process (including many millions of civilians in Asia), and then had the gall to try to bargain for decent surrender terms after all that horror they caused? Applying that standard, there would not be a single American left alive for the constant war they wage since the end of WW2.

The key difference is that Japan was defeated utterly; the US was never even close. The last fighting we did on our home soil was the Civil War; discounting that, 1812.

In warfare more than almost anything else, might matters.

Re: Scene report from the Chernobyl Zone

#230
post #215

Earlier quoted context omitted.

Mmm, that isn't strictly true. From what I've read his anarchist-leaning sailing documentary "Hold Fast" is... controversial, in sailing circles.

I enjoyed watching his documentary, but I'm not part of sailing circles. In what way is it considered controversial?

Disclaimer: I also am not in sailing circles and also have not seen the documentary in question - I'm basing this impression entirely on the hearsay of an extensive Reddit thread (that I cannot alas find again) full of sailors who had no idea about Moxie's other life. The objections I remember were:

-incompetent sailing

-criminal behaviour (or more likely faked criminal behaviour) including theft

-making a big show about being poor and bohemian when in fact they had loads of cash (some of which was spent on the boat offscreen, rather subverting the message)

This is exactly the same kind of pseudo-rebellious sketchiness as pretending to ride your motorcycle illegally through Chernobyl, when in fact you took the official tour.

(I have just queried a sailing IRC channel and got a similar response, so I don't think I'm misremembering.)

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