All of our radio signals since it's inception hasn't travelled far enough to matter. Even after short distances, out radio signals would be indistinguishable fr

All of our radio signals since it's inception hasn't travelled far enough to matter. Even after short distances, out radio signals would be indistinguishable from noise. If humanity stood on an alpha Centauri planet, our closest star, we wouldn't be able to detect life on Earth with the current tech we have.