[capitan_refugio]

I'll take your word for it regarding earthborne radioactivity sources. I seem to recall that the effectiveness of a scintillometer drops off exponentially with respect to the distance away from the source. However, I also recall that one particular U-2 instrumentation package included a dust collector, wherein the dust could be analysed for telltale radioactive particles. Or is this in the realm of sci-fi???

[Boot Hill]

capitan_refugio says:   "I also recall that one particular U-2 instrumentation package included a dust collector, wherein the dust could be analysed for telltale radioactive particles."

The dust particles that the U-2 collected were generated by nuclear detonations, not from radioactive sources (weapons or other) stored here on the earth. Much of the confusion about this was generated by satellite radiation detection systems like SABRS and RADEC. While many thought these systems were capable of detecting nuclear weapons, the reality was that they were only designed to detect nuclear weapon detonations. Because of natural background radiation, you have to be within 30 meters (or so) before you can detect the radiation from an unexploded nuclear weapon.

Regards,

Boot Hill