Jill Tarter

They’re herrrrre! No, not the extraterrestrials, the media. Sometimes it seems to me that filming, photographing, and chronicling us has become its own growth industry. On the one hand, that’s good, because it means people are interested (as you appear to be, because you are reading this), and new people who don’t yet know about us may find out from the media efforts. On the other hand, that’s bad, because it means that our observing sessions sometimes turn into three-ring circuses with lights and mikes and people everywhere. Fortunately our observing system is now so clever and reliable that it takes care of itself, and we can spare the time to interact with the media. Our team is getting pretty good at speaking slowly, not using our hands too much, eschewing mathematics and the technical jargon that really does make it easier for us to have internal discussions. And, of course, we try to keep it fresh to answer nearly the same questions in new and interesting ways—again and again. My colleague Seth Shostak is particularly adept at this; I keep trying to pick up tips from him.

The trouble is that when I try too hard, I sound a little like a TV evangelist—perhaps the Church of Jill. Short answers are best; long answers get “preachy.” It’s hard to distinguish what we know (or think we know), what we infer from that, and what we are merely speculating about without being able to quote statistics or resort to those wonderful “approximately equal to” and ~ symbols. It’s no good saying, “Trust me, I know what I’m talking about”; therein lies the church. I need to provide simple answers without overstating my case. This is actually easier to do one-on-one. The way a person phrases a question indicates his or her level of understanding, and I can then build my answer on that. The generic answer for the faceless audience is a lot harder to get right. Let’s see how I do with you. Why do I work on this project? Because it’s so important. The results of this work will calibrate humanity on a cosmic scale. For as long as anyone’s been keeping track, humans have been asking whether we share the universe with other sentient beings. I think it is fantastic that I live in the first human generation ever to have the technology necessary to try to answer that ancient question by doing experiments. I cannot imagine working on anything more important.

Why do I believe that there is intelligent life elsewhere? I don’t believe—I admit that I don’t know what the answer is. That’s why we are doing the experiments; we may discover an answer. I do think it is plausible that extraterrestrial intelligence may exist somewhere else in the cosmos. Life started quickly on the nascant Earth, in the blink of a cosmic eye, over 3.8 billion years ago. In our own Milky Way galaxy there are hundreds of billions of stars, many just like our sun, and there are hundreds of billions of galaxies in the observable universe. Environments similar to the early Earth are therefore likely to be abundant, and life may have also started quickly in them. Cristian deDuve puts this most eloquently when he states that “Life is a cosmic imperative.” Missions now being planned by NASA and ESA for the next two decades may inform us whether deDuve is correct as well as eloquent. As for intelligent life, Richard Dawkins may be on the right track when he argues that intelligence is the inevitable outcome of a predator-prey “arms race.” Or maybe Gaylord Simpson is closer to the truth in his claims of the “nonprevalence of humanoids.” SETI in its current, or some future, configuration is one way to try to find out. There are no guarantees.

We are a very young technology in a very old galaxy—but we’ll leave that until tomorrow. I’m going to go search for Pioneer 10 now.

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Note: On Tuesday, Slate posted an erroneous headline on the Table of Contents that described SETI’s work as “searching for UFOs.” SETI does no such thing, and click here to find out why not. Slate sincerely regrets the error.