>>11315378>https://www.sciencedirect.com/science/article/abs/pii/0019103575901165i can't see that source since i'm too lazy to log into my library proxy right now. give me a quote where it actually says that?
what is the reason it "attenuates"? cosmic dust or something? that doesn't seem like a good argument. i would buy it more if you said something along the lines of "the signals go below the background after so and so many light years" but i still think a radio observatory like the ones we have on earth can eliminate most backgrounds from other stars by focusing in on a narrow region of the sky. heck, they made that picture of the black hole at the core of the galaxy using radio astronomy
i'm not saying you're wrong about communications radio signals are too weak to pick up on say an FM radio on the moon, but with a proper radio telescope aimed at the FM broadcast tower you could surely do it. and i don't see how a similar principle doesn't extend to interstellar stuff, without something more quantitative about your supposed "attenuation" or at least something about a background noise that would drown out the signal
