The Search For Extraterrestrial Polluters

So how do you go about spotting an alien civilization? Well, you build a really big radio telescope and point it at the stars. But say if ET isn't transmitting? Say if ET is transmitting, but they are too far away? What if our alien neighbors decided not to transmit radio waves? What if they're [...]

Published On 10/19/2009
8:15 PM EDT