An interesting story on Seth Shostak’s recent appearances in Athens, OH ran today in The Athens News. In a pair of talks Shostak, senior astronomer for the SETI Institute (Mountain View, CA), explained to a general audience why he thinks extraterrestrial life is out there. He even gave a timeline for its discovery: within the next two dozen years (he went on to bet each member of the audience a cup of Starbuck’s coffee on the proposition). Each SETI experiment, Shostak added, gathers more data than all the previous ones combined.

Deep in the article are two Shostak suggestions for extending the SETI search. First, focus on the same area of sky for longer periods of time, instead of today’s common practice of looking at a star for a few minutes and then moving on. Keep a longer gaze and look for signals of short duration that may repeat every few hours or days.

The second tactic: work harder on binary systems. These may contain technological civilizations that have explored both sides of their twin solar systems (inevitably, Centauri A and B come to mind). If two members of a binary system line up properly from our vantage point — and if the two systems are talking to each other — then there is a possibility for detecting their powerful, tightly focused communications.

Centauri Dreams‘ take: Believing that technological civilizations are rare in our galaxy (and elsewhere, for that matter), I doubt either of these strategies will succeed. But I’m all for SETI proponents who say we won’t know until we try. If ever there was an argument I would be happy to lose, it’s this one, but I’ll let someone else take Shostak up on that two dozen year bet.