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.
Several years ago, NYC and North Jersey put out public service announcements warning about what to do if there is a nuclear attack. I think that the NYC one can still be found on the internet. When I saw those warnings back then, I thought it was a com that you know who was threatening to set off a nuke in that area (near Trump's golf course in Bedminster, btw). Then there was the "earthquake" in north Jersey near Bedminster. Then, a year or so later, drone swarms in the same area. I'm thinking that the sum of all fears, if it takes place at all, will be there.
The drone swarms were nation wide too, they checked everywhere. I drove cross country for thanksgiving and saw them in the midwest chicago farm highways area. That was actual months before they were on TV so we had no idea what it was except it was a lot of them and they were stopping and going vertical. And looked closer than they were because as we kept driving they didn't go past as quickly as we expected. They were bigger and farther than drones should have been if they were normal size drones.
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.
This is so interesting.
Several years ago, NYC and North Jersey put out public service announcements warning about what to do if there is a nuclear attack. I think that the NYC one can still be found on the internet. When I saw those warnings back then, I thought it was a com that you know who was threatening to set off a nuke in that area (near Trump's golf course in Bedminster, btw). Then there was the "earthquake" in north Jersey near Bedminster. Then, a year or so later, drone swarms in the same area. I'm thinking that the sum of all fears, if it takes place at all, will be there.
The drone swarms were nation wide too, they checked everywhere. I drove cross country for thanksgiving and saw them in the midwest chicago farm highways area. That was actual months before they were on TV so we had no idea what it was except it was a lot of them and they were stopping and going vertical. And looked closer than they were because as we kept driving they didn't go past as quickly as we expected. They were bigger and farther than drones should have been if they were normal size drones.