In the second part of my E-mail chat with Seth Shostak, coauthor of the new book Cosmic Company and a leader in SETI (the search for extraterrestrial intelligence), the astronomer gives his thoughts on the likelihood of alien contact and what would happen next.
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Next News: Do you think aliens have visited here, perhaps using some sort of advanced technology like a bias drive or Alcubierre "warp drive"?
Shostak: It's not impossible to come here. You don't even need terribly advanced technology, if you're willing to tolerate long travel times. And after all, the Earth has had detectable life (which would be given away by the composition of our atmosphere) for a few billion years. So one cannot rule out the possibility that aliens visited Earth during, say, the Triassic, and took a few dinos back as specimens. We cannot prove that didn't happen. But on the other hand, there's no credible evidence, in my view, that aliens have visited the Earth (more particularly, not in modern times). It's an appealing idea, and one that spawns endless TV shows, but the evidence on the ground is very, very thin.
Next News: What do you think happened at Roswell . . . really?
Shostak: I think that what happened at Roswell is well and truly the crash of a military balloon train launched from the nearby Air Force base (they were making these launches on a regular basis in 1947). This experiment (Project Mogul) is well documented, and as an explanation of the "incident" in Roswell only incredible to those who make a living by suggesting that aliens somehow crash-landed there. It's been more than a half-century since the purported crash. Can anyone point to anything that we've learned from Roswell?
Next News: So you're not a conspiracy theorist?
Shostak: I think it's worth pointing out a misunderstanding that I hear a lot: many folk believe that a SETI discovery would be covered up, in the same way that they believe that crashed aliens would be efficiently collected by the government and secreted away. When asked why they expect such a paranoid scenario, the usual response is that "the public couldn't handle the news." Well, as we point out in the book, roughly half the populace believes that the aliens are already here, buzzing the Earth. They don't seem to be panicked in the streets about this. The whole idea that learning we aren't alone would inevitably brew widespread chaos is contradicted by this fact.
Next News: OK, then, let's say a radio astronomer discovers the Signal–a series of prime numbers or such. What happens next? What is the procedure? In Contact, for instance, the black helicopters were on the scene pretty fast. When is the president contacted?
Shostak: In fact, unlike in the movies, it would take several days–maybe even a week–before SETI scientists would be quite sure that the signal was truly extraterrestrial. All during that time, the story would be leaking out (there's no policy of secrecy. In fact, SETI researchers have agreed that if they get a signal, they ultimately call other astronomers, at other observatories, to get them to verify the transmission.) The story would break in a very messy fashion, I imagine, with the least reputable media running the story even before the scientists were sure that the signal was real. Of course, SETI will notify the government once it is very certain of the result, but by then the President (and everyone else) will have heard the story on the nightly news. There's little point in revving up helicopters of any color. You can't shut down a signal from space (the location and frequency are already known by astronomers around the world), and of course there's no danger from receiving a radio signal anyway
Next News: What do you see as the societal implication of finding 1) life, and 2) intelligent life?
Shostak: I think both discoveries would have profound (but not shocking) effect. If we were to find microbes living a few hundred feet under the rusty, dusty surface of Mars, that would prove in a moment that biology is commonplace–and if you are inclined to believe that life is a miracle, then you would have to say that it's a miracle that occurs all over the place–which to me takes it out of the miracle category! (The one exception to this is if it turns out that Martian life is similar to terrestrial life, and the Red Planet merely "infected" the Earth long ago . . . )
Finding intelligent life would affect us more deeply. We like to think that we're special, and that understandable anthropocentrism is reflected in the special place humankind occupies in most of our religions. We may be the children of God, but if we discover intelligent extraterrestrials, we will suddenly be confronted with the fact that God has many children. That may be a useful antidote to our usual hubris.
Next News: Do you believe in panspermia, the theory that life on Earth was seeded from space microbes?
Shostak: There's no evidence that this happens. But it's not ruled out, either. Various people have made estimates of the probability that infected rocks from one star system could reach another, and–depending on your assumptions–this seems possible. Of course, you might wonder what's the relevance of panspermia? Doesn't this simply "push" the question of how life got started to some other planet, without explaining anything? In fact, if it occurs, panspermia could do a little better than this. It could reconcile a possibly unlikely start of life (that is, maybe biology is very hard to get started) with its widespread occurrence. Turning nonliving chemicals into life might be difficult, and yet the universe could be stuffed with biology, if panspermia is an important mechanism. I think the best thing to do is run some experiments with our spacecraft to see if spores are floating around the cosmos.
Next News: Does your exploration of the universe make you more or less likely to believe in a Grand Designer behind it all?
Shostak: I don't see evidence for "intelligent design," which is to say, the necessity of a mechanism other than Darwinian evolution to produce the structures we find in earthly life. I don't, however, think that this somehow rules out God. I simply believe that, if God exists, then his operations are far more subtle than we like to assume.
