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FrozenGate by Avery

Radioisotopes Are Your Friends

I think it must have been a fair bit more than that:

Reported yield was 15 kt of TNT, or about 6E+13 joules. Given the fission energy of 1 kg of U235 is about 1.4E+14 joules per kilogram, the amount that fissioned should have been 400 grams or so. I did these calculations quick and dirty so don't blame me if they are off by a bit, but it's nothing near 'the weight of a dollar bill'.

It is however equivalent to converting something like 1.2 grams of matter to energy, which would be about the weight of a dollar bill.

On the other hand, very little of the uranium actually fissioned: the yield came from less than a kilogram of the uranium, while the whole thing had 64 kg of it.
 





I think it was a Vsauce video.

https://www.youtube.com/watch?v=SHZAaGidUbg at the 1:15 mark.

He got the info from a book, but it could have been like you said converting matter to energy and was merely misinterpreted.

Still, it was a tiny amount that fissioned compared to the amount that was in the bomb.
 
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This is a perfect example of why I don't get my news, or information for that matter, from YouTube. People who don't really understand the physics involved, but love to hear themselves talk, are all over this clap trap espousing theories they don't actually know and have embedded "experts" speak for less than a few seconds to give credence to what they are trying prove. It is full of incorrect information that usually young people then use a a reference to some knowledge they now claim to have.
 
Long before Trump’s Fake News;
The Era of Fake Knowledge: Why It's Never Been Easier To Fake What You Know
By Shane Parrish • 06/06/14 9:00am
“It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so.” — Mark Twain

Recently, Karl Taro Greenfeld, a journalist and author, published an op-ed in the New York Times on faking cultural literacy.

“It’s never been so easy,” he wrote, “to pretend to know so much without actually knowing anything. We pick topical, relevant bits from Facebook, Twitter or emailed news alerts, and then regurgitate them.”
Click to expand...
 
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I want to read that "Command and Control" book now though. It sounds like an interesting read.
 
That link to "The era of fake knowledge" is a good read, Mac. It seems quite relevant to today. It is too easy to skim the internet about a subject, and after reading a little, act like we know what we are talking about. There really is no substitute for actual knowledge, and as long as no one calls us out on it, makes one seem like they know what they are talking about.
 
I often wonder if today the world would be powered more by nuclear energy if it wasn't for mishaps like Chernobyl and Three Mile. Most of the accidents with fission power have been due to poor choices and human error, and I think if better systems had been in place those accidents may not have occurred, and public perception of nuclear power would be a lot better.

Personally, I think nuclear power in the form of fission now, and hopefully fusion in the near-ish future is our best bet for producing clean energy. Nuclear waste is a lot easier to manage and contain then pumping out tons of Co2 and other gases from burning coal and other fossil fuels.
 
I don't know where you got the idea that nuclear waste is easy to dispose of. It is the single most difficult problem that has always faced the nuclear energy industry. And the decay time for it is very long in comparison to other toxic substances. It is why there are no new nuclear plants being built in this country. When one can guarentee the containment of nuclear waste products for 20,000 years, we will have the problem licked.
 
It's kind a funny that they'll calling it "Nuclear Waste" and on same time NASA has been building and developing RPS devices >> (formerly known as RTGs on SNAP program) which are using this so called "waste" as their power source. Why all this misrepresentation for? -Yes, some of those materials can be dangerous when mishandled but they'll should educate people more for it instead scare people and create mass hysteria.

I think on that Galen Winsor’s talk, he is pointing out the physical value of the irradiated material that some people insist on calling high level waste.

He asks the final important questions – “Who owns the plutonium?” and “How much is it worth?”
He recognizes that using it beneficially threatens a number of powerful interests.

In this 2006 IECEC document they won't call it waste >>
 
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I think it is the sheer mass of all the radioactive material which is no longer usable in the reactors that it came from that makes this a problem. The amount of high level atomic waste from reactors increases each year by 12,000 metric tons. It is considered hazardous for about 1 million years. When you consider this amount of high level waste material is an amount the size of two skyscraper buildings, it is now a huge amount of radioactive material that will remain so for an incredibly long period of time. How are we to contain this much material and keep it safe for that long a period of time?
 
Blarg King said:
I think it was a Vsauce video.

https://www.youtube.com/watch?v=SHZAaGidUbg at the 1:15 mark.

He got the info from a book, but it could have been like you said converting matter to energy and was merely misinterpreted.

Still, it was a tiny amount that fissioned compared to the amount that was in the bomb.
Click to expand...

I think he got it wrong there. The 1.38% that actually fissioned sounds correct to me, but since there was 64 kg of the uranium in the bomb, that'd be in the order of a kilogram or so*. He then wrongly says the thing about the uranium being the weight off a dollar bill - the mass defect of the reaction is about that amount.

*this is in the same order of magnitude i calculated by the reported blast yield and energy density of U235 fission.

As for highly radioactive material being waste or useful product: That depends mostly on demand i suppose. The material that goes into RTG's for spacecraft is very useful in that application, but if you had to get rid of it on earth it'd be considered very dangerous waste.

This also goes for less active material: It is waste if you bury it so nooone ever touches it again, but the low level heat produced by it could also have some practical application as long as you get the shielding right. It'll not produce enough heat to run a power plant, but it could heat a swimming pool if you used separate closed loop systems and heat exchangers.
 
Oh FFS, we've known for decades how to deal with radioactive 'waste'. Park it in front of an accelerator and hammer it with protons. Make those unstable atoms a bit more unstable so they decay now instead of over 100's or 1000's of years. This has the side benefit of generating lots of heat, enough to run a power plant on. The power generated is more than enough to run the accelerator with some left over to sell. The end product will contain some activation products but these decay relatively quickly such that the waste from this kind of accelerator driven reactor will be less radioactive than the original uranium ore in 100 years or so. No millennial storage required. The catch here is spent fuel reprocessing, a dangerous and toxic affair.
 
Benm said:
I think he got it wrong there. The 1.38% that actually fissioned sounds correct to me, but since there was 64 kg of the uranium in the bomb, that'd be in the order of a kilogram or so*. He then wrongly says the thing about the uranium being the weight off a dollar bill - the mass defect of the reaction is about that amount.

*this is in the same order of magnitude i calculated by the reported blast yield and energy density of U235 fission.

As for highly radioactive material being waste or useful product: That depends mostly on demand i suppose. The material that goes into RTG's for spacecraft is very useful in that application, but if you had to get rid of it on earth it'd be considered very dangerous waste.

This also goes for less active material: It is waste if you bury it so nooone ever touches it again, but the low level heat produced by it could also have some practical application as long as you get the shielding right. It'll not produce enough heat to run a power plant, but it could heat a swimming pool if you used separate closed loop systems and heat exchangers.
Click to expand...

So basically just a miss-quoted comparison with regards to the Little Boy.

With regards to nuclear waste, I feel if properly dealt with by sealing it tight and burying it deep well away from populated areas, its a relatively easy byproduct to control. I also agree with your idea of re-using it as a source of heat.

I wish more research was being done into molten salt reactors. They seem to have the potential for cleaner and safer operation than light water reactors. The designs that use thorium seem especially safe, since thorium is a lot less "hot" than the enriched uranium fuel rods, and the half life of the waste is a much shorter 300 years.
 
I'm not really sure where the confusion came from, but the idea is that if you were to have half a gram of antimatter annihilate half a gram of matter, the energy released from that would be comparable to a (by current standards tiny) bomb like little boy.

As for nuclear 'waste': i'd suppose getting the maximum usable energy out of it. As long as it produces usable amounts of low temperature heat it can have applications in industrial and even domestic heating systems.

After that long term storage should be used, but the benefit is that the activity is much lower at that point and shielding the radiation is not that problematic either.

Shielding doesn't have to be very thick or bulky either - i've visited nuclear plants and stood at the edge of the pool where the store freshly spent fuel rods in. This stuff is still so radioactive you can see the blue glow of cherenkov radiation coming from it, but storage under 10-15 meters of water is plenty to be perfectly safe to look at it. Obviously falling into that pool would be very bad, but otherwise there is no problem.

Nuclear technology has an image of being extremely dangerous, which it can be, but i can also be very safe under most conditions. I've had the the chance to go into a couple of nuclear reactor facilities and seen both aspects of it.

Also i'd like to note that the most deadly incidents have been from chemical, not nuclear, factories. Something like chernobyl may seem like the worst industrial accident ever, but it is not, by far.
 
One of the worst I can think of was an amonium nitrate explosion in Texas City during WW II. It was actually thought to be benign and a ship full of the stuff went off and pretty much destroyed the harbor and killed many people. Destroyed a large chunk of the town too, IIRC.
 
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