Radiation, even shielded, gives off heat (detectable from satellites and aerial drones) and causes various types of shielding to emit detectable chemical fumes...which can be picked up by aerial drones and filters.
Radiation, even shielded, gives off heat (detectable from satellites and aerial drones) and causes various types of shielding to emit detectable chemical fumes...which can be picked up by aerial drones and filters.
Understood. So if someone walked one across the desert open border, it may show up on a satellite infra red photo but by then wouldn't it be too late? By the time an analyst saw it and get some action the thing could be in Dayton.
For a drone to pick up an emitted gas, it would have to be "droning" overhead at that exact moment. Do we have drones constantly patrolling the entire Mexican border 24/7?