Not very far, I’m afraid, and within that little radio sphere there just aren’t many stars with potentially habitable planets. There are, however, about 5,900 stars, many with planets, within that radio sphere.

Unfortunately, every time the distance the radio waves travels doubles in size the signal gets 4 times weaker. So at the outer reaches the radio signals would be virtual indistinguishable from background static. By the time the signals reach the other side of the galaxy, over 100,000 years from now, humanity may not even be existing anymore. Who knows? And if somehow an alien over there was able to distinguish our radio waves from the background noise and sent a response, that response wouldn’t arrive here until over 200,000 years from now.

It kinda puts a damper on the whole “communicate with the aliens” theory.