Aliens on Line 1

For one evening, it looked like we finally had an extraterrestrial signal.

One day it happened. A signal was sent through space and picked up by a telescope tucked in the West Virginia mountains. The author’s colleagues analyzed the data. Was it a signal from intelligent life on another planet?

We thought we had found E.T.

It was early on a summer evening in 1997. I had just finished dinner, and although I don’t recall the fare, I do recall the post-prandial excitement. Tom Pierson, the SETI Institute’s chief executive, called me at home and suggested that I hightail it down to the office.

“We’ve got a signal,” he said in his trademark deadpan, “and it’s looking good.”

After a short drive to our headquarters in Mountain View, California, I walked into the labyrinth where the institute’s scientists and engineers work. I found them decamped to an adjacent hallway, where a long table with a row of monitors was pushed against a wall. A half-dozen sleepy people were seated facing the table, their eyes fixed on the monitors, which were displaying a teeming grid of data. The numbers told a simple story: A narrow-band signal—millions of times more spectrally compact than a TV broadcast—was coming from the skies.

More than 2,000 miles away, in the foothills of West Virginia’s Allegheny Mountains, the director of our SETI team, Jill Tarter, was at the controls of the National Radio Astronomy Observatory’s 140-foot antenna. We had been using that instrument for only a few weeks when it spit out this promising result. The incoming data were being transmitted to the institute’s computers in California, where the team there was watching.

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This story is a selection from the September issue of Air & Space magazine

There was an air of tempered excitement, and not just because we had found a signal. After all, when you pair a large antenna with a receiver tuning in 10 million frequency channels, you pick up signals several times a minute. These are caused by the thick fog of human-generated radio interference that blankets our world. Despite the obvious jokes, it’s easy to find intelligent life on Earth. But in this case, the signal had passed a simple test: When the antenna was moved away from the sky position where it had been aimed, the signal disappeared. When it was spun back, the signal returned. The nodding of the antenna had gone on for hours.

This was the first and most important requirement for any claim of success. We were picking up a narrow-band emission—a type that only transmitters make—coming from a position that seemed fixed relative to the stars. In years of trying, we had found no other signal that had been so promising. Could this be the real deal?

There wasn’t much for me to do to help answer that question, other than look at the monitors and chat with the tense crowd. I was nervous. If this really was proof that the galaxy had other technologically advanced societies, then a news story more shocking than John Kennedy’s assassination was about to break. That would seriously disrupt the workaday lives of all of us in that room, but more importantly would change the future of our species. It was a lot to process, and I paced the office, snapping occasional photos to distract myself.

As the clock edged toward morning, our target star system dropped to the western horizon. Soon, it would set just as the sun and moon do, becoming invisible to our antenna for 12 hours. We weighed the possibility of calling someone at a radio telescope in Europe or Australia to see if they could continue the observations, but we weren’t sufficiently confident that our detection was really that of an alien broadcaster. One of our scientists, John Dreher, well known for being brighter than the average bear, was checking the signal frequency to see if it matched that of any known Earth satellite.

Several team members used the forced intermission to peruse a document known as “the protocols” that had been drafted in the 1980s by SETI scientists in case an alien signal was detected. It should have been the perfect resource in the current situation.

The protocols were elegantly phrased, and simple in principle. We were advised to carefully check any promising signal. If we confirmed that it was truly extraterrestrial, we should share the news with the world and refrain from transmitting any reply without some sort of international approval.

We were still at step one.

I went to my desk to await the reappearance of the target, and sleepily mused on the fact that, contrary to what some might have expected, no men in black had shown up at the SETI Institute’s front door. There was no call from the Pentagon or the White House. Indeed, no one phoned at all.

That changed mid-morning, when a science reporter at the New York Times rang up. He had been tipped off to what was going on. No surprise there: The SETI community is not enamored of secrecy. He casually asked me to tell him about “the signal.” I replied that we were, indeed, checking out a promising candidate and suggested he call back in three hours.

By then, Dreher had tracked down the source of the excitement: It was a telemetry signal from SOHO, a solar research satellite operated by NASA and the European Space Agency. The false alarm was the product of a short chain of unlikely events. We had fallen victim to a chance geometric alignment of our radio telescope with SOHO; a second antenna in Georgia normally used to verify signals had been out of action for a few days.

No aliens were talking to us yet. In retrospect, I’m glad that we finally had a dry run of the time—possibly not far off—when we get a real signal.

And we had learned something. The SETI protocols, while well intentioned, aren’t particularly useful in real life. Yes, of course any promising signal should be checked thoroughly, but you don’t need a protocol to understand that. And the stipulation to tell the world is as useless as hair gel for Mr. Clean. The incident demonstrated that any promising signal will become public knowledge immediately, even though it will be days or weeks before it’s rigorously confirmed. While that fact should quiet those who think that any detection of alien intelligence would be kept under wraps to avoid panic among the populace, the corollary is that in the future, you should expect to hear about some signals that look good but, after a few days of checking, don’t pan out. As soon as an interesting signal tickles a radio telescope, scientists will start tweeting and blogging. You can bet on it.

The last protocol point, about sending a response, is a sensitive issue in some quarters of the scientific community. But realistically, if the aliens are hundreds or thousands of light-years away, there’s no particular hurry to agree on a message and transmit it.

Looking back, our experience in the summer of 1997 was momentarily exciting but ultimately disappointing. We hadn’t found E.T. But since then, the instrumentation used for SETI experiments has become substantially faster at processing all the observations they make—a trend that keeps me optimistic about future success.

Until you’ve really found something new, you’re empty-handed. Then, overnight, a discovery is made, and the world changes.

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