I don’t know how I missed this, but I didn’t learn about Benford Beacons until I listened to the most recent installment of Planetary Radio. Maybe this SETI idea is reaching some sort of critical mass so it’s getting harder to avoid. With good reason, I think. The idea comes from Gregory Benford, astrophysicist and science fiction author, his brother James Benford, a physicist studying high-power microwaves, and Gregory’s son Dominic Benford, a NASA scientist.
Their notion is that radio signals from our cosmic brethren in distant star systems may not come in the form of constant or long-term broadcasts. Our far-off companions may not have the resources to blast hugely powerful signals over long time periods in all directions. This would take tremendous power. Instead, they might send targeted, short, microwave blips in our direction–signals much like the famous “Wow” reception of 1977. This blip would be repeated at unknown intervals.
Once a signal is recognized, we could look and listen in that direction with more sensitive instruments and possibly find a lower-power signal that is more constant and information-rich (and cheaper for ET to send).
The Benfords have some very specific and well-reasoned ideas about where to listen and what frequencies to listen to. This astronomynow.com article explains it better than I can. The exciting part is that if their ideas are correct, then current SETI efforts have for the most part looked at the wrong frequencies and sometimes in the wrong direction. It’s an avenue of exploration that we can follow with current technology.
Chances of success are unknown, but nothing ventured, nothing gained. I’ve speculated before that if we succeed, we might even find ourselves listening to the galactic equivalent of the Nigerian e-mail scam. Recently I read a Charles Stross short story that fleshes out this very scenario. On the other hand, assuming there are aliens who are enough like us that we could actually understand them–they might have some interesting information to pass along, recipes to share, gossip, warnings, advice, good stories, things we didn’t want to know, and embarrassing family photos.