What are the chances that current SETI programs will succeed?
The answer depends on how many intelligent species are presently sending out signals that we’ re capable of picking up. People have been playing this entertaining guessing game ever since Frank Drake wrote down his famous equation and have come up with answers ranging from zero to enormous. It all hinges on the initial assumptions you make. At least now we can be pretty confident that planetary systems are fairly common, and the scientific consensus is leaning toward Parkes Radio Telescope the view that life will come about whenever it gets the chance. The big questions concerning which we have few clues are: (1) How often does life become intelligent (human level or greater)? (2) How often does intelligence develop advanced technology (capable of interstellar communication?)(3) How often does a communications-capable species make a sustained effort to send messages? (4) How often, on average, does a communicating race survive? An optimist might argue that intelligence confers such a b
