Im sorry for my mistake I thought it was the upcoming launch. I still will not be suprised if Pakistan and Iranian officials attend the nuke test.
You can detect an underground nuclear explosion. There are seismic stations all around the world to find “abnormal” seismic activity. There are something around 300 seismic stations around the world looking for cheaters.There are detectable concentrations of the rare gases argon-37 and xenon-133 at 50 and 80 days, respectively, after the detonation.