08-17-2017, 08:32 PM
Radio beams can be directed, whether focused as they are when used for radar, or by using the same phenomena as are used to generate laser beams (aka masers).
Laser beams can be detected off to the side if there's enough matter (dust clouds) in the way to cause scattering of some of the photons. Of course, the signal level would be far lower than if you were in the line-of-sight.
Laser beams can be detected off to the side if there's enough matter (dust clouds) in the way to cause scattering of some of the photons. Of course, the signal level would be far lower than if you were in the line-of-sight.
Selden