### The long search

"The Search for Extra-Terrestrial Intelligence: Necessarily a Long-term Strategy" is the title for Jill Tarter's Seminar About Long-term Thinking this Friday. There's no deeper question than "Are we alone in the universe?" And there's no quick way to answer it. Slow, steady science is the hardest to fund and organize, but Jill Tarter has been working on the question for 30 years and the SETI Institute (which she co-founded) for 20 years. The work has had incremental jumps in capacity, such as with the seti@home program (the first major peer-to-peer application) and with the Allen Telescope Array, coming on line later this year.

Jill Tarter holds the Bernard Oliver chair and directs the Center for SETI Research at the SETI Institute in Mountain View. Interested in the subject since the mid-70s, Dr. Tarter first published on SETI in 1977. Recipient of numerous prizes and awards, Dr. Tarter has lately expanded her activities to include helping educate the next generation of scientists. She was the model for the Ellie Alloway character in Carl Sagan's 1985 novel _Contact_ and the 1997 movie starring Jodie Foster.

"We are the first generation of humans who can investigate for signs of other intelligences in the universe," began Jill Tarter at the July 8-9 Seminar About Long-term Thinking. All we have to find is one case for the universe to appear utterly different to us, because finding one will guarantee there are many.

"Anybody we find," she went on, "will be older than we are. SETI was rightly characterized right back at the beginning of the idea in 1959 as 'archaeology of the future'-- their past, our future."

"We can't detect intelligence at a distance, so really SETI is SETT-- the Search for Extra-terrestrial TECHNOLOGY." Jill thinks that the technological Singularity feared by some won't happen, "because in nature all exponential growths saturate at some point." If, however, technologies always self-extinguish, then we will find no one (and presumably we will eventually join the great silence). But if technologies at least sometimes stabilize, or even keep on accelerating, and they bother to communicate, we could gradually build a catalog of the ways technology can develop, to better guide our own.

In Earth's history inferior technologies have always been crushed by the "guns, germs, and steel" of superior technologies. Isn't contacting civilizations certain to be superior to ours asking for serious trouble? You can't catch a cold through the phone, Jill pointed out. The effect of ET contact is more likely to be what Europe experienced when it reached back in time for the culture, science, and technology of the Classical era (and across Asia via the Mongol Empire for the "compass, gunpowder, and printing" of China): the result of those contacts was the Renaissance.

As Jill chronicled the history of SETI, I was impressed at how limited the search has been so far, even though 101 targeted and survey searches have been reported since around 1974. If the nearest star, Alpha Centauri, were leaking TV and radio signals like Earth is, we would not detect it-- yet. The SETI Institute is now building at Hat Creek, California, a 300-times improvement on previous search technology-- the Allen Telescope Array (initially funded by Paul Allen; $16 million is needed to complete it). It will have 350 ingenious dishes (designed by Jill's husband Jack Welch) arrayed in a Gaussian random pattern. The next stage would be a Square Kilometer Array, offering 100-times better still power, for a cost of $1 billion. Then really good listening could be done from the far side of the Moon ("the only place in the Solar System not exposed to Earth's electronic noise").

Jill's catalog of search technology to come (she's a self-confessed hardware geek) had a piece of stunning news, at least to me. If computation keeps getting better and our radio-telescopy keeps improving, we should know by 2040 whether or not there's anyone out there, at least in our galaxy. That's soon! And huge.

On of Jill's slides quoted cartoonist Walt Kelly (via Porkypine): "Thar's only two possibilities: Thar is life out there in the universe which is smarter than we are, or we're the most intelligent life in the universe. Either way, it's a mighty sobering thought."

What about Earth transmitting instead of just listening? Jill noted that for a signal to go out and be answered could take up to 200,00 years. (That's within our galaxy; for the next galaxy over it would be millions of years.) She ended her talk: "Who should talk for Earth? The winders of the Clock of the Long Now. What should they say? The Library of human culture. You could call it… 'the long hello.'"