"Stable" here means mechanically stable (they don't fall apart as quickly as was expected), not radiologically stable (the radioactive elements, of course, still decay at their normal rate).
It means "mechanically stable", which could be either good or bad depending on the question, but is generally a limited good thing.
At the least, it means these particular compounds aren't quickly breaking down into ever-smaller nano-particles that can be absorbed into living things.
This is tangentially related to the article, but it's interesting that the phrase "unexpectedly stable" triggers positive connotations. It did for me as well.
But the phrase is actually neutral, it's not making any claims if stability is a good or bad thing in this context, neither about "unexpected" stability. But given the larger context of language we read it as positive.
It’s hard to call them “rods” at this point, since they melted and then cooled into tiny metallic droplets and shards after they were ejected in the explosion.
For radionuclides more long-livd means less radioactive per unit of time, though. Of course uranium compounds can be toxic in the chemical sense as well, but I’m unsure if uranium compounds make it to the top threats in that list compared to e.g. arsenic and lead.
Of course radioactivity needs to be respected, and the exclusion zone is there for a reason due to factors such as hot spots.
This is "long-lived" in the ecological sense, not radiological. The grains of uranium oxide dust remain grains of uranium oxide dust, rather than breaking apart. If you ingest a few molecules of uranium oxide, it pretty much doesn't matter, you're fine¹. Ingest these dust particles, not so much. It's a question of concentration, and it seems that it's not diluting out naturally.
(P.S.: the radiological stability and lifetime of uranium doesn't make much sense to question; the dust flakes aren't large & concentrated enough to significantly shorten their half-life due to their own neutron emissions cascading and this isn't what the study was researching. Note the article talks about weathering: "It remains largely unclear why these particles weather at different rates in their environment.")
Much safer than newly built reactors using decades old designs for making Plutonium used as power generators, with every safety feature forcefully disabled and during a drill to investigate the feasibility of a condition live, the effects of which weren’t known by any operator and the drill hadn’t been tested in an offline experiment before nor was it even simulated. Then, maybe.
> A series of 50-kiloton bombs would be dropped into the cavern and exploded to heat the water and create steam. The steam would then power a secondary cooling loop for power extraction using a steam turbine. Dropping about two bombs a day would cause the system to reach thermal equilibrium, allowing the continual extraction of about 2 GW of electrical power
For some reason (that I haven’t figured out yet) thermonuclear bombs are just so much more efficient than any other proposed fission or fusion reaction.
It’s strange that controlled fusion is an energy sink, but whatever black magic is happening inside an H-bomb manages to unlock so much “free” energy.
Fusion is ridiculously efficient and effective power source. The problem with it is that it is very hard to created conditions where fusion can happen. The one reliable way we have that doesn't take more energy in than it outputs, is to detonate a fission bomb and use the x-rays to compress a fusion secondary.
The history of fusion research for the past 70 years is trying to figure out a cost-effective way to trigger enough fusion to make net energy without a nuke. So far, we've got bupkis. (The magnetic containment approaches using high-temperature superconductors seem promising, but we won't know they actually work until we've built them.)
Even the cleanest bombs (97%+ fusion rather than fission) turned out to be too dirty for basically everything civilian (unlocking gas reservoirs - too radioactive; landscaping to replace enormous amounts of conventional explosives - too radioactive).
Not really making nukes take a ridiculous amount of energy and you only get to use it once where the energy to create ITER gets split across its operating lifespan.
Further fission here requires a fission first stage which represents a huge additional energy input.
The efficiency is higher because the device is bigger. To oversimplify a bit, the surface area through which energy is radiated away grows slower than the volume containing the fuel. So heavier fuel "pellets" in bombs (ones in the kilogram to ton range) have a much easier time burning efficiently than the tiny milligram scale fuel pellets at NIF. Tiny fuel pellets cool down too fast. Likewise, multi-megaton fusion bombs are more efficient than the "little" sub-megaton bombs that the US favors (for reasons of compactness/deliverability) in its nuclear weapons stockpile.
Fission fragment rocket engines are also (theoretically) extremely efficient.. using the particles that come out of the reaction directly as a high-velocity exhaust stream.
Practical for many missions, just not for sending humans in person to other planets. For example, consider a mission to deliver a telescope out past 550AU so that it can use the whole sun as a gravitational lens. That’s more than 11× further than Pluto, but a fission fragment drive could get the telescope out there in about the amount of time it took New Horizons to fly past Pluto.
"Stable" here means mechanically stable (they don't fall apart as quickly as was expected), not radiologically stable (the radioactive elements, of course, still decay at their normal rate).
Thank you! Geigerclickbate?
The headline sounds weirdly positive... but it's "stable" as in [ed.: ecologically] "long-lived". Very much not a good thing.
It means "mechanically stable", which could be either good or bad depending on the question, but is generally a limited good thing.
At the least, it means these particular compounds aren't quickly breaking down into ever-smaller nano-particles that can be absorbed into living things.
This is tangentially related to the article, but it's interesting that the phrase "unexpectedly stable" triggers positive connotations. It did for me as well.
But the phrase is actually neutral, it's not making any claims if stability is a good or bad thing in this context, neither about "unexpected" stability. But given the larger context of language we read it as positive.
I think they mean that the fuel rods are not breaking down, aka leaching into the environment, as fast. That's a good thing.
It’s hard to call them “rods” at this point, since they melted and then cooled into tiny metallic droplets and shards after they were ejected in the explosion.
For radionuclides more long-livd means less radioactive per unit of time, though. Of course uranium compounds can be toxic in the chemical sense as well, but I’m unsure if uranium compounds make it to the top threats in that list compared to e.g. arsenic and lead.
Of course radioactivity needs to be respected, and the exclusion zone is there for a reason due to factors such as hot spots.
This is "long-lived" in the ecological sense, not radiological. The grains of uranium oxide dust remain grains of uranium oxide dust, rather than breaking apart. If you ingest a few molecules of uranium oxide, it pretty much doesn't matter, you're fine¹. Ingest these dust particles, not so much. It's a question of concentration, and it seems that it's not diluting out naturally.
¹ humans contain, on average, 90µg of uranium. [https://www.iaea.org/sites/default/files/DU_Eng.pdf]
(P.S.: the radiological stability and lifetime of uranium doesn't make much sense to question; the dust flakes aren't large & concentrated enough to significantly shorten their half-life due to their own neutron emissions cascading and this isn't what the study was researching. Note the article talks about weathering: "It remains largely unclear why these particles weather at different rates in their environment.")
40 years and counting, vs 1 year for Hiroshima
It was a power plant full of fuel, why is this surprising?
190 tons of nuclear fuel, vs 64 kilograms.
Basically, nuclear bombs are much safer than nuclear power plants.
Much safer than newly built reactors using decades old designs for making Plutonium used as power generators, with every safety feature forcefully disabled and during a drill to investigate the feasibility of a condition live, the effects of which weren’t known by any operator and the drill hadn’t been tested in an offline experiment before nor was it even simulated. Then, maybe.
Nuclear bombs are meant to go boom. Any part that doesn't go boom is waste whose weight could be better allocated to making it have a bigger boom.
next step: use nukes as an energy source
Check out this 1970s project that proposed extracting electricity from thermonuclear explosions.
https://en.wikipedia.org/wiki/Project_PACER
> A series of 50-kiloton bombs would be dropped into the cavern and exploded to heat the water and create steam. The steam would then power a secondary cooling loop for power extraction using a steam turbine. Dropping about two bombs a day would cause the system to reach thermal equilibrium, allowing the continual extraction of about 2 GW of electrical power
There was also project Plowshare, as chronicled by Kurzgesagt at https://www.youtube.com/watch?v=h3DCdWyb0cc
Which was building canals etc with nuclear bombs. https://en.wikipedia.org/wiki/Project_Plowshare
In the end we're just boiling water.
"Hey boss, do you think there is a chance this scheme might introduce radioactive byproducts into the ground water?"
"Shut up"
[dead]
Coming soon: thermonuclear fracking.
Already done https://en.wikipedia.org/wiki/Project_Gasbuggy
There goes another grant proposal into the bin...
[dead]
For some reason (that I haven’t figured out yet) thermonuclear bombs are just so much more efficient than any other proposed fission or fusion reaction.
It’s strange that controlled fusion is an energy sink, but whatever black magic is happening inside an H-bomb manages to unlock so much “free” energy.
Fusion is ridiculously efficient and effective power source. The problem with it is that it is very hard to created conditions where fusion can happen. The one reliable way we have that doesn't take more energy in than it outputs, is to detonate a fission bomb and use the x-rays to compress a fusion secondary.
The history of fusion research for the past 70 years is trying to figure out a cost-effective way to trigger enough fusion to make net energy without a nuke. So far, we've got bupkis. (The magnetic containment approaches using high-temperature superconductors seem promising, but we won't know they actually work until we've built them.)
Even the cleanest bombs (97%+ fusion rather than fission) turned out to be too dirty for basically everything civilian (unlocking gas reservoirs - too radioactive; landscaping to replace enormous amounts of conventional explosives - too radioactive).
Not really? How do you define efficiency here?
Thermonuclear bombs literally create lots of heat, and don’t tend to drive anything that produces work. It’s the opposite of efficient.
Just like lighting gasoline on fire and claiming that that’s more efficient than a combustion energy…
I’m talking about net energy. Harnessing it is a whole different story.
Not really making nukes take a ridiculous amount of energy and you only get to use it once where the energy to create ITER gets split across its operating lifespan.
Further fission here requires a fission first stage which represents a huge additional energy input.
GPT pro says 3 to 30x energy release compared to the entire supply chain input for a megaton class weapon.
I trust the argument. You can look into it yourself. Long story short, it is massively energy positive compared to controlled fusion.
What if we used them to run Tesla turbines
In order to trigger an H bomb, you first trigger a regular fission bomb to generate the necessary energy to trigger the second fusion stage.
So, fission bombs are the black magic.
I think there’s a lot more to it than that, like the heavy uranium tamper, “FOGBANK”, and radiation implosion (whatever that means).
It’s a much more efficient version of inertial confinement fusion like at the NIF.
The efficiency is higher because the device is bigger. To oversimplify a bit, the surface area through which energy is radiated away grows slower than the volume containing the fuel. So heavier fuel "pellets" in bombs (ones in the kilogram to ton range) have a much easier time burning efficiently than the tiny milligram scale fuel pellets at NIF. Tiny fuel pellets cool down too fast. Likewise, multi-megaton fusion bombs are more efficient than the "little" sub-megaton bombs that the US favors (for reasons of compactness/deliverability) in its nuclear weapons stockpile.
Some of the nuclear rocket propulsion ideas propose exactly that, like Project Orion.
Fission fragment rocket engines are also (theoretically) extremely efficient.. using the particles that come out of the reaction directly as a high-velocity exhaust stream.
FFR have super high ISP but microscopic thrust. Not exactly practical.
Practical for many missions, just not for sending humans in person to other planets. For example, consider a mission to deliver a telescope out past 550AU so that it can use the whole sun as a gravitational lens. That’s more than 11× further than Pluto, but a fission fragment drive could get the telescope out there in about the amount of time it took New Horizons to fly past Pluto.
For that particular mission I’d be curious to compare to an ion drive architecture.
Don't ion drives consume comparitively a lot of xenon to work?
Yes, they have substantially lower specific impulse than fission fragment.
If you like Orion check out Project Pluto (they even built some some test bench engines)
did they ever figure out how to brake? Spin the ship 180 degrees and bomb the front?
Couldn't you just turn and orbit ?
… without irradiating yourself?