satellites cannot take air samples. Countries use balloons to sample air flowing from nuke sites in Eastern Europe and Iran to see what kind of isotopes are present and in what concentrations, for example. And at lower altitudes, you can also get better sideviews, if you are carrying cameras.
“Countries use balloons to sample air flowing from nuke sites in Eastern Europe and Iran to see what kind of isotopes are present and in what concentrations, for example.”
Gathering data for Russia?