SETI: What to Do if a Signal Arrives

by Seth Shostak - Senior Astronomer

Jan. 25, 2001

Looking for aliens can be cold and lonely work, just ask Agent Mulder. Better yet, ask Frank Drake. Four decades ago, when Drake was the only SETI scientist on the planet, he would single-handedly tune the receiver on his radio telescope in the chilly West Virginia mornings.

He was prepared for discomfort. But he was less prepared for success. In 1960, Drake was hoping to eavesdrop on radio signals that might be coming from either of two Sun-like stars, Tau Ceti and Epsilon Eridani. These stellar neighbors are about a dozen light-years from Earth, and Drake was inspecting them with an 85-foot (26-meter) diameter antenna.

Then it happened. Tau Ceti had just eased below the horizon, so Drake swung the telescope toward Epsilon Eridani. To his surprise, the loudspeaker began to bray with a loud "wham." Drake was surprised. "Could it be this easy?" he thought. And then he pondered, "what do I do next?"

In fact, it wasnt that easy, and he didnt have to do anything. The provocative "wham" was human-made interference, not a signal from the Epsilon Eridani star system.

In the ensuing decades, SETI grew from a lone wolf project to an effort involving a worldwide pack of scientists. Realizing that finding a signal would, of course, happen unexpectedly, the researchers decided that it would be a good idea to formulate a plan of "what to do next."

And formulate they did. Most of the sweat equity was contributed by John Billingham and Jill Tarter (now at the SETI Institute) together with Michael Michaud (currently retired), together with their colleagues on the SETI Committee of the International Academy of Astronautics (IAA). In 1989, they submitted to the academy a short document with a long title: "A Declaration of Principles Concerning Activities Following the Detection of Extraterrestrial Intelligence." It was an action plan in case a signal was found.

Although approved by the IAA and a gush of other space and astronomy groups, the declaration is really only a gentlemens agreement. It has no force of law -- after all, who could or would enforce it? On the other hand, all the major SETI research teams have said they will abide by it if their telescopes pick up a faint buzz from space. The contents of the declaration are all maternity and apple pie: check the signal to be sure that its truly extraterrestrial, then notify the astronomical community, the government and the public (the order is unspecified).

In other words -- no secrecy. That may sound like a no-brainer, but in the past some astronomical discoveries have been kept secret, at least for a while. When pulsars were first found by English astronomers in 1967, there was confusion about what they were. Initially dubbing their discovery LGMs, for Little Green Men, the astronomers considered, semi-seriously, that they might have tripped upon alien broadcasts. Months passed, and only when it became clear that a natural explanation for the pulsing signals was in the offing did the astronomers make their find public. The declaration makes it clear that, in the case of a real LGM signal, the world should be told. And for reasons well discuss next time, this not only makes sense, but in fact cant happen any other way. Agent Mulder might be able to keep his investigations under wraps, but SETI research is as open as the Great Plains. If the astronomers hear a signal, youll be hearing from the astronomers.