These would be detectable. Nuclear material would put out small amounts of radiation. Although its possible if they are shielded by a large enough amount of water, radiation could be 100% blocked from nearly any scannable methods.
One completely unblockable nuclear emission is neutrinos. Those can't be blocked by anything - a neutrino can penetrate the entire planet. They pass through matter without interacting so easily they are also VERY difficult to detect.
I have been thinking about those drone swarms a few months ago with this in mind. Regular radiation sensors would work in planes. Satellites. Trucks. Drones wouldn't be needed. But neutrino detectors would have a very low chance of detecting anything so they would need to be deployed in large scale numbers. And if neutrinos are detected, capable of moving to zero in on the source to triangulate an unknown nuclear material source.
If I was searching for hidden nuclear weapons, I would build a swarm of large drones. Large size necessary for both neutrino detection - it can't reliably be shrunk much as they almost all need to be heavy and as big as possible - and for the longest loiter times possible because even the best neutrino detectors have a difficult time finding neutrinos. I would make swarms as large and wide as I could manage, as that helps increase detection through sheer numbers and area. And drones also make the whole detector array capable of moving wherever needed next, and adapting size/density when zeroing down on a suspect.
Also, I recall a story where one of those drones was shot down or crashed and first responders were told it was hazmat. Neutrino detectors at this size and distributed use would almost definitely include hazardous material, something like heavy water (hazard but mostly don't touch) to chlorine (very hazardous, don't be anywhere near). I never followed up on that story to see if evidence of what type of material they were worried about.
Fruitless. Neutrino detectors are huge and massive in order to detect anything. Unless you have exceedingly subtle data processing and lots of data, you would be mainly picking up the neutrinos emitted by the sun.
You can make a large distributed detector and put the individual nodes on drones
each node not such a great detector, a swarm of nodes multiplying effectiveness. Each drone would still need to be fairly large. And likely hazmat. Something like this could conceivably scale to the largest neutrino detector in existence easily.
And you would need to spend a large amount of time trying to find neutrinos. The odds of people noticing an operation like that are pretty big, I suspect it would make national news after a few months of flying under the radar
No, you can't. You have no idea how large these detectors are. As big as a school-bus might come close. Big as a small building, at least. You need to have it large in order to correctly correlate scintillations to determine if a neutrino has transited the detector.
If you are looking for nuclear materials, I doubt there will be much success. Both uranium and plutonium decay by alpha emission, and that can be totally shielded.
Think nuclear suitcase bombs hidden in cities around the world.
These would be detectable. Nuclear material would put out small amounts of radiation. Although its possible if they are shielded by a large enough amount of water, radiation could be 100% blocked from nearly any scannable methods.
One completely unblockable nuclear emission is neutrinos. Those can't be blocked by anything - a neutrino can penetrate the entire planet. They pass through matter without interacting so easily they are also VERY difficult to detect.
I have been thinking about those drone swarms a few months ago with this in mind. Regular radiation sensors would work in planes. Satellites. Trucks. Drones wouldn't be needed. But neutrino detectors would have a very low chance of detecting anything so they would need to be deployed in large scale numbers. And if neutrinos are detected, capable of moving to zero in on the source to triangulate an unknown nuclear material source.
If I was searching for hidden nuclear weapons, I would build a swarm of large drones. Large size necessary for both neutrino detection - it can't reliably be shrunk much as they almost all need to be heavy and as big as possible - and for the longest loiter times possible because even the best neutrino detectors have a difficult time finding neutrinos. I would make swarms as large and wide as I could manage, as that helps increase detection through sheer numbers and area. And drones also make the whole detector array capable of moving wherever needed next, and adapting size/density when zeroing down on a suspect.
Also, I recall a story where one of those drones was shot down or crashed and first responders were told it was hazmat. Neutrino detectors at this size and distributed use would almost definitely include hazardous material, something like heavy water (hazard but mostly don't touch) to chlorine (very hazardous, don't be anywhere near). I never followed up on that story to see if evidence of what type of material they were worried about.
Fruitless. Neutrino detectors are huge and massive in order to detect anything. Unless you have exceedingly subtle data processing and lots of data, you would be mainly picking up the neutrinos emitted by the sun.
You can make a large distributed detector and put the individual nodes on drones each node not such a great detector, a swarm of nodes multiplying effectiveness. Each drone would still need to be fairly large. And likely hazmat. Something like this could conceivably scale to the largest neutrino detector in existence easily.
And you would need to spend a large amount of time trying to find neutrinos. The odds of people noticing an operation like that are pretty big, I suspect it would make national news after a few months of flying under the radar
No, you can't. You have no idea how large these detectors are. As big as a school-bus might come close. Big as a small building, at least. You need to have it large in order to correctly correlate scintillations to determine if a neutrino has transited the detector.
If you are looking for nuclear materials, I doubt there will be much success. Both uranium and plutonium decay by alpha emission, and that can be totally shielded.