To start off the proceedings, Frank Drake, the father of SETI, worried that the switch from analog television and radio signals to digital cable and satellite radio would render Earth invisible to aliens looking for other life. Right now, the Earth is surrounded by a 50-light-year thick cloud of radiation, starting with Hitler's opening address at the 1936 Olympics, and ending with this morning's broadcast of the Rachael Ray Show. But as more and more people receive their media beamed down to them from digital satellites, not up to them from analog radio towers, that signal slowly fades away, drastically reducing the chance that aliens might detect our tiny blue rock.