Senior astronomer Seth Shostak on the “Search for Extraterrestrial Intelligence”

By Hana Baba

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If you take the train or the freeway south this weekend, through the Peninsula, into the South Bay, and you end up in Santa Clara, you’ll be just in time for a very special, first of its kind event. This weekend is the first annual convention of the SETI Institute, SETI is short for “Search for Extraterrestrial Intelligence.”

It’s a gathering of astro-physicists, evolutionary biologists, geneticists and astronomers who all have one thing in common – they are in search of life outside planet Earth. But don’t confuse them with astrologists and the UFO crowd. Seth Shostak is a senior astronomer at the SETI Institute, host of KALW’s radio show “Are We Alone?” and a self-proclaimed alien hunter. KALW’s Hana Baba asked him what exactly he’s looking for.

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HANA BABA: So, you call yourself an alien hunter, and that’s the title of your book, “Confessions of an Alien Hunter – a Scientist’s Search for Extraterrestrial Intelligence”, and at SETIcon you will be presenting a speech on, when you find the signal – not if, when – you’ll find the signal. So when you say you’re searching for extraterrestrials, what are you looking for exactly?

SETH SHOSTAK: Well, we don’t actually look for the extraterrestrials themselves, because that would involve them coming here – we can’t go there, our rockets just don’t go nearly fast enough. So how could you find them? You can do what SETI experiments do and that is, that you direct a telescope, a radiotelescope, a big antenna, for example, and you aim it at the sky, in the direction of nearby star systems, hoping that maybe one of them has a planet where ET is hanging out and you try to eavesdrop on their signals. In the same way that ET could find out that there is intelligent life on Earth by picking up the signal from KALW, for example.

BABA: Why are you so sure that they have signals that they transmit?

SHOSTAK: Well, obviously, we don’t know that they do and that is really the purpose of the experiment, but, it is true that we are broadcasting into space, not deliberately, but we’ve been sending television signals into space since the war, really, at high power. And that means that “I love Lucy”, every day, washes over a new star system. That’s just going into space willy-nilly, it wasn’t “broadcast” out there, but the signal scoots out there, across the rooftops of the city wherever the transmitter is and then eventually it just keeps going in a straight line right out into space. And so there is this sort of inadvertent transmission, this noise from Earth that would tell somebody we’re here. Look, if we’re doing this only 100 years after Marconi, only 100 years after the invention of radio, it’s hard to imagine that a society that was thousands or millions of years more advanced than ours wouldn’t have this technology.

BABA: What makes you so sure there is extraterrestrial life – that might be a very basic question, but what evidence, to you, is most compelling?

SHOSTAK: Well, there isn’t any evidence of extraterrestrial life, compelling evidence, yet; in fact, the bottom line is, there isn’t – we haven’t found ET and frankly, we haven’t found pond scum. We haven’t found dead pond scum. But, I think that situation is going to change in the next couple of decades and the reason is that the searches are getting so much better. We’re sending space craft, of course, to Mars. There may be life on Mars. What you have to do, probably, to find it, is drill a hole a couple of hundred feet deep and pull up the muck at the bottom of that hole and look at it under a microscope and you might see martian pond scum. You might say, I don’t know, do I care about that? Do I want to spend my tax dollars looking for Martian pond scum? Because you know, I’ve got earthly pond scum in the bathtub at home.

But if you found life on Mars then you would know that life is just some sort of cosmic infection, it’s not something miraculous because look, two worlds have it, so there must be many more. All these things are possible but we haven’t found them yet and I think that the reason that I remain optimistic that we will, are just developments in mostly astronomy, and the fact that we’re learning that planets are just as common as fire hydrants – they’re all over place. The best estimates for the number of worlds in our own galaxy, the number of planets – a trillion. A trillion! That’s a big number.

BABA: Let’s talk about another area. How are we to make the distinction between what’s science and what’s pseudoscience, you know, there are so many skeptics and nay-sayers, yet you and your colleagues are astronomers, geneticists, evolutionary biologists, you’re doing real scientific research about this. How do you get people to take what you do seriously and not dismiss it as out-of-this-world mumbo-jumbo?

SHOSTAK: Anybody who would go to our observatory, for example, and look at the actual experiment would see that it really has the hallmarks of science becuase it’s not like for example, looking for Big Foot, where you send some guys out into the woods with a pair of binoculars and a videocamera and hope to find it. This is all grounded in terms of calculations that show what frequencies can travel through the interstellar medium, that can go from one star to another in a reasonable way, without being blocked by interstellar gas and so on. There is science behind the hypothesis.

But beyond that, it’s being conducted in the way science is conducted. In other words, you say “Look, we think they might be out there. One way you could find them is if you could find a signal that had the characteristics of a signal made by a radiotransmitter. So let’s build the equipment that could find that.” We don’t say “We found’em” until we find them. In other words, this is not like the UFO hypothesis which says that the aliens are here and we claim that they’re here and you can believe or not believe it. If we claim that we found a signal, of course, anybody with an antenna, anyone in the world can go verify that – that’s the hallmark of science. You can do the experiment too, and you can just decide for yourself whether that signal is there or not. The government can’t hide that at “Area 51” or some such place – the signal is up in the sky and anyone can get to it.

BABA: So to me, it sounds like, since we haven’t yet found evidence, as you’re saying, of alien life, that this search may actually be driven by a belief that there’s life out there, rather than scientific proof. Which to me would seem ironic, that the scientists, many of whom consider faith and belief to be non-scientific values, are throwing all of this behind a belief rather than science. Has anyone said that to you before?

SHOSTAK: Maybe you should look at this as exploration. Consider when they were trying to find the Northwest Passage, they didn’t know for sure that it existed, but you would not say that it’s a religion to look for the Northwest Passage or to look for Antarctica. For thousands of years, people had speculated that maybe there’s a big hunk of land, a continent or something, down at the bottom of the world. And you could sit around in the bars of Europe and discuss it ad infinitum, but in the end, you’d do the experiment – you’d send some ships down there and say well, do you see it or not, is it there or not there? This is the same sort of deal.

Everything we’ve learned about the universe suggests that we’re not terribly special, not astronomically, not in terms of the physics or the chemistry that’s going on here – there’s nothing we can point to and say “You know, this is the only place in the cosmos that’s going to have these conditions” – we simply can’t do that. So, if you want to assume that, well, nonetheless, we are the smartest things in the universe, we’re the only planet that has intelligent life, that would be a miracle beacuse that would make us incredibly special. And so it’s a very resonable hypothesis –  you can call it a belief if you like, but it’s a hypothesis, that there is something to be found.

BABA: Why are you doing this? Why do you think it’s useful for us to know about life on other planets? Is there a benefit to humanity, or is it not really about that?

SHOSTAK: In the first instance I’d say it’s not really aboout that because I think it’s about curiosity It’s OK that 99 percent of the population doesn’t have very much curiosity, that’s OK. But if 100 percent of the population doesn’t have curiosity, you get a situation like in ancient Egypt where the whole society, the whole culture eventually stagnates. That’s not good, it’s like ants, you have to have a certain percentage of ants that wander around just of aimlessly, they don’t follow all the other ants along in a line, they go out and look for new food. So curiosity pays.

You could say, what was the purpose of sending Captain Cook to the South Pacific, looking for Antarctica, which he did a couple of times, what possible benefit could there be from that? These are things you do because you’re curious and curiosity has always paid off in the long term for society. Now, I hear a lot of people saying “I’m spending all of my tax dollars on these NASA projects and NASA is sending all of these motorized skateboards to Mars, what’s in it for me?” If you look at it carefully, for every dollar you spend on NASA, you get ten dollars back in terms of commercial products and commercial activity and so forth. So even just from a straight economic point of view, it’s a good thing to do baisc research, but I think there’s more to it than that – it’s just knowing things. What was the purpose of having Copernicus say that the Earth is not the center of the universe? How much is that worth?

BABA: I’m going to play Devil’s advocate one last time. What if someone were to say to you, “You know, I lost my job, I’m dealing with the economy, health care and my children can’t be bused to school anymore because of budget cuts. I’m not going to spend my time worrying about outer space when I need to take care of my Earth”?

SHOSTAK: People are perfectly free to say that. This is not a tax-supported project so if they don’t want to support or don’t want to think about it, that’s perfectly OK. I encourage people to think about it but if they don’t want to, that’s entirely up to them. But the argument that because of all the difficulties we have in the world today, that somehow we should stop doing basic research, that I do have an issue with because that’s extremeley myopic. That’s worse than having said, back in the 1800s to the kings of Europe, “You’re supporting this guy Wolfgang Mozart, all he’s doing is writing music – we’ve got people dying in the street of hunger and you’re giving him money to write music, what a waste, let’s stop that right now.” I don’t think that would have been a good move. To begin with, you don’t feed a lot of people with the amount of money you were spending on Mozart, but beyond that, in the case of SETI or space research today, the amount of money being spent, it’s less than being spent on cat food every day, that’s for sure. It’s a very tiny fraction of the economy. And yet, this is the thing that guarantees that your country, and for that matter the world, has a future.

BABA: If there’s one thing you’d like the public to understand about your work, and SETI, and a scientific search for extraterrestrial intelligence, what would that be?

SHOSTAK: A lot of things.The public thinks we’re  broadcasting and that we’re waiting for a response, and so forth. There are a lot of misconceptions about the nature of the project. I would say this: This is a project that rests entirely on the interest of the public. One of the reasons we’re having this SETIcon conference is to get the public involved. Because it’s privately funded. If the public isn’t interested, this project stops. And the interesting thing for them to know is that the idea that there might something up there in the sky that’s as clever as we are is a very old idea. I’m sure the Neanderthals thought about it too – everybody has thought about it. What’s interesting is that now, finally, at the beginning of 21st century, we can actually do an experiment. And the experiment makes sense, on paper, it doesn’t depend on hyper-dimensional physics, or anything science-fictiony – it can actually work. And that makes us a special generation. It’s a little like after 1492, one generation had the opportunity to map the Earth and they did that. We have the opportunity to find out how special we really are.

The SETIcon conference takes place August 13 -15 at the Hyatt Regency Hotel in Santa Clara.

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