signals from civilizations that would be quite far away. there's to danger in that, of course. you tune in the radio, you don't have to worry about the deejay jumping into your home and giving you a hard time. that's a completely harmless sort of thing and interesting because it would tell you whether earth is really, really special, or whether there is enormous quantities of life out there. >> larry: but, david, one thing is has done with stephen hawking about it, it has opened many eyes, hasn't it? >> oh, yes. the problem is that everybody seems to have their own idea, of course, of what aliens ought to be like. we all say of course our broadcasts have already been detected by now. when seth himself has calculated and most of the astronomers have calculated that our tv broadcasts actually dissipate pretty soon after they leave our solar system. it's these narrow beams that are being sent out from taxpayer-paid observatories like