November 13, 2011

Battling the giggle factor in the search for extraterrestrialintelligence

Dr. Bernard Bates is fascinated by the search for extraterrestrial intelligence, but acknowledges there’s a certain “giggle factor” about the endeavor even as 21st-Century observatories discover planets in orbit around faraway stars on an almost daily basis. Bates, astronomy instructor at the University of Puget Sound, gave an informative and humorous talk this week titled, “The Quiet Sky: Searching for Extraterrestrial Intelligence.” The event at the Swiss Pub in Tacoma was part of the Science Café series presented by the Pacific Science Center and KCTS9 television.

SETI is listening, but is anyone talking?
Surely part of the giggle factor comes from a half century of listening for electromagnetic transmissions from ET without hearing a peep. Bates said as technology improves so does the hunt, and suggests we give it another 40 years or so.

“If Moore’s law [about rapidly doubling computer power at lower cost] continues, if we don’t stumble upon someone by 2050, we’ve done something wrong,” he said.

That something could be in the design of the experiment.

“The worst assumption we made was that somebody is out there transmitting,” Bates said. “Someone would have to come up with funding on another planet to just send out signals for no apparent reason for a long time.”

Perhaps cash-strapped governments in other systems decided it was cheaper to just listen. Earthlings, on the other hand, have been broadcasting for a little over a century, and the original transmissions of Gilligan’s Island are now crackling out near Theta Boötes. Bates said if we were out there we would figure it out.

“We are really good at what we do. With the technology we have right now, we could find ourselves a quarter of the way across the galaxy,” he said.

It has been 50 years since Frank Drake cooked up the equation which now bears his name as a device for thinking about the factors that affect the chances of intelligent, radio-beaming civilizations appearing around the galaxy. In 1961 all we had for the seven variables were wild guesses. But now we have a pretty good idea about the astronomical variables: the rate of star formation, the fraction of stars with planetary systems, and the number of planets in each system that could support life. That part of the Drake equation suggests there should be 10 civilizations in the galaxy that are emitting electromagnetic signals. Bates said we’re still a little fuzzy on the rest of the variables.

“All of those cannot be incredibly small probabilities, because we’re here,” he noted, so the final answer has to be at least one. “But we just don’t know. Each of those variables represents an area of active research in different disciplines.”

Why all the fuss about SETI? Bates said his nine-year-old daughter drove the point home when she observed recently that she never sees two of anything. There is either just one, or there are many. Bates thinks that may go for extraterrestrial life, too.

“If we find a second genesis within the solar system that means there are probably a lot of them,” he said. “It’s hard to believe that there would only be two examples of life originating in the entire galaxy.”

Bates thinks most of the people working in the field believe there is at least simple life out there.

“It’s complex life that is hard,” he said. “Intelligence might be something that is so rare or so hard to come by that it never appeared again. There might be so many little accidents that had to happen in order for intelligent life to appear that we’re just it.”

Bates thinks we should keep at it, even if we don’t have a clear signal from another civilization by 2050.

“In the end, the worst that could happen is that we just give up and say, ‘OK we’re it. There’s no one else out there to talk to.’”

You can view the entire talk by Bates on the KCTS9 website.

No comments:

Post a Comment