We send messages all the time, free of charge. There's a big shell out there now, 80 light-years around us. A civilization only a little more advanced than we are can pick those things up. — Frank Drake Copy Share Image
The problem here is that a civilization that is 1,000 light years away doesn't know we exist. They don't know that we have radio telescopes here on Earth because they see Earth as it was 1,000 years ago. Nothing can… — Paul Davies Copy Share Image
