The first radio waves escaped earth’s atmosphere over a hundred years ago, heading into the universe in all directions at once. While they will eventually dissipate into nothingness, they be detectable in a radius that’s many. many light-years long.
You remember Contact, right? Radio astronomer Jody Foster became the first to detect extraterrestrial life when they beamed back Hitler’s TV speech from the opening ceremonies of the 1936 Berlin Olympics.That was an interesting wake-up call–and theoretically very, very possible.
Another variation on that theme is Year Zero which tells of how the universe was bankrupted after aliens stole all our music and had to pay for the copyright violations. It’s very funny.
This is a long introduction to LightYear.fm which illustrates how the farther you go away from Earth, the farther back in time you go when it comes to our broadcasts. Click on the image to see what I mean.