Douglas Vakoch, PhD, likes to say that he spends half of his time searching for life on other planets and the other half trying to understand life on this one.
Vakoch, a clinical psychologist, is perhaps the only "director of interstellar message composition" in the world, a position he holds at the Mountain View, California-based SETI Institute. SETI, which stands for Search for Extraterrestrial Intelligence, is a 30-year-old nonprofit research institution where a staff of about 90 scientists combs the universe for signs of life. Over the years, such luminaries as Carl Sagan and SETI pioneer Frank Drake have been affiliated with the institute.
Vakoch, who is also a professor of clinical psychology at the California Institute of Integral Studies, is the only social scientist among the astronomers, physicists and biologists there. As a child in the 1960s obsessed with space exploration, he thought he'd grow up to be an astronomer or physicist, too.
"But in college, I decided I was more interested in people than stars," he says. He majored in religion and went on to earn his doctorate in clinical psychology.
Still, he kept up his interest in life beyond Earth. "When I chose to get my doctorate in clinical psychology, I wondered whether I'd become a full-blooded psychologist or find a career in SETI," he says. "But I chose psychology because if we want to communicate with ETI, what better to communicate about than what we are? And what better background is there for that than psychology?"
The constraints of communication
While completing his psychology training, Vakoch began to write papers and give talks to the SETI community, using his background in psychology and behavioral and social science to broach a new way of thinking about the challenges of communicating with extraterrestrial intelligence.
"From the outset [of SETI efforts], the idea had been that if you can build a radio telescope, [extraterrestrials] would understand our math, understand our science," he says. "And that struck me, even in my early 20s, as not that plausible."
In the early 1970s, for example, NASA sent the "Pioneer Plaques" aboard the Pioneer spacecraft, the first ships designed to achieve escape velocity from our solar system. The plaques, intended to be a message to any extraterrestrials that might find them, contained drawings of nude humans, and pictorial symbols representing our solar system and a hydrogen atom.
But Vakoch pointed out to the SETI astronomers and physicists that even if intelligent extraterrestrial beings understood, for example, the chemical composition of the universe, they might have such a radically different way of representing it that our pictograms would be completely uninterpretable.
Eventually, as Vakoch's work became known, the SETI Institute offered him the half-time position of director of interstellar message composition. There, for the past decade and a half, he has continued to contemplate what humanity should say to extraterrestrials, assuming we ever get the chance.
"The title really just reflects Doug's interests," says Seth Shostak, PhD, the astronomer who directs the Center for SETI Research at the SETI Institute. "Very little of this is being done. Doug is sui generis."
Vakoch has brought a few other social and behavioral scientists into the SETI fold. Psychologist Donald Hoffman, PhD, a professor of cognitive science at the University of California, Irvine, studies visual perception and builds robotic vision systems. Vakoch came across his work and saw a connection to SETI, Hoffman says. Though Hoffman hadn't studied SETI before, Vakoch asked him to write a paper on the implications of human vision research for SETI communication.
In the paperopens in new window, which Hoffman presented at a 2002 conference on interstellar communication, he argued that images are not in fact the "universal language" that SETI astronomers thought.
Laypeople and scientists who don't study vision tend to think that human vision works like a camera, passively recording scenes. But years of research shows that instead the human brain actively constructs what we see from the ambiguous visual data our eyes take in, using rules that have developed over hundreds of thousands of years of evolution. And there's no reason to think that extraterrestrials would have evolved the same rules that we did, or would be able to interpret or even "see" our images the way we intended — especially given that even different species on earth have evolved such different perceptual systems.
"The actual [visual] content that we try to communicate [to extraterrestrials] I would say is almost surely not going to be received in the way we intended it," Hoffman says. "We don't even understand the perceptual world of an ant, and we've been living with them a long time."
Given that reality, Vakoch says, the key is to think about how we could "communicate something meaningful, given the constraints of communication."
One idea, for example, would be to start with the most basic math. "Any civilization that can communicate should know that two plus two equals four." And then, with that basis, we could work up to communicating more complex math, including game theory — which can also transmit something about the idea of cooperation.
Reaching out
Even as Vakoch's and others' work has laid out the challenges of communicating with life on other planets, the chance that such life exists seem to be increasing. Less than three decades ago, astronomers had yet to identify a single planet orbiting a star other than the sun. Today, we know that most stars have planets, and that perhaps 20 percent are in a habitable temperature zone.
"Over the last 20 years, the chances have improved tremendously for life being out there because we know there's a lot of real estate where it's possible," Vakoch says.
As those chances have improved, a controversy has emerged in the SETI community: whether or not to engage in "active SETI," or broadcast targeted messages to locations more likely to contain life, rather than just passively "listen" with radio telescopes.
Vakoch has been a prominent voice in favor of active SETI, but he has many opponents. Recently, a group of 28 scientists signed a petition calling for a moratorium on active SETI until a "global consensus" was reached on whether and how to do it. Signers included SpaceX and Tesla founder Elon Musk and astrophysicist and science fiction writer David Brin.
The active SETI opponents invoke what might be thought of as a "War of the Worlds" argument — basically, do we really want to let potentially unfriendly and dangerous aliens know that we're here?
But Vakoch and other supporters of active SETI say the "hostile aliens" argument is moot. Any extraterrestrial intelligence might already be picking up old episodes of "I Love Lucy" and all of our other radio and television broadcast signals, so we might as well try to send a more targeted message.
And Vakoch thinks that the time to try active SETI is overdue. "We've always assumed that if the other civilization has the ability to communicate, they'll take on the burden of contacting us," he says. "That's not at all obvious to me."
The debate played out at a panel last spring at the American Association for the Advancement of Science, where Vakoch and Shostak debated Brin. The discussion garnered some media attention (see further reading box) for a topic the general public doesn't hear much about. But given the controversy, active SETI is unlikely to happen any time soon even though the technology to try it is easily available, Vakoch says.
"The fact that it is contentious means that it's difficult to move forward," he says.
So does all of this leave Vakoch frustrated? The fact that, for now at least, we can only listen for signs of extraterrestrial life? And that after decades of listening, we haven't heard a peep? And that there's a good chance that we won't in his lifetime? And that even if we did, his and others' work suggests how difficult it will be to understand each other?
"SETI is not a field for those who need certainty," he says. "You have to be willing to invest your time in a project with no guarantee. With psychology, you go into a lab and at the end either have evidence that supports your hypothesis or not. But we could go on for hundreds or thousands of years, and not get any signal, and still not be sure that we are alone."