Jill Tarter:

So let me just start by saying that I am not Jodie Foster. I do however get to do the job that her character, Ellie Araway, did in the movie Contact. However, I don’t wear headphones except for really cheesy Halloween costumes. My computers do the job of searching for signals, looking for patterns in noise that could be generated by a signal that was engineered rather than a signal that was produced by nature. This might be a way of finding out whether there are any other technological civilizations out there.

Jill Tarter:

I love what I do. I’m never going to get very rich at it, but my life is very rich indeed. I get to spend every day trying to figure out puzzles, trying to answer questions that I’ve asked, actually humanity has asked for thousands of years, and sometimes I get some answers. Sometimes I figure out things that no one else has yet figured out, and so it’s a very rich life indeed. And while I may never have a great big corner office on Wall Street, I in fact do have some pretty spectacular scenery in my job.

Jill Tarter:

This is the world’s largest radio telescope on the island of Puerto Rico. It’s a big sink hole. It’s a big thousand foot hole that’s lined with metal panels and 500 feet above it, there’s a superstructure with receivers that capture the radio waves. And I got to sit out on the cables, these big bridge strands that hold up this superstructure.

Jill Tarter:

I work with radio telescopes. Now, I suspect most of you are more familiar and have probably looked through an optical telescope. So optical, radio, they’re just different parts of the electromagnetic spectrum, waves. Optical waves are really short. Cram a few million of them in a meter. Radio waves are much longer. A few hundred would fit in a meter for the shortest radio waves, and some radio waves are many meters long. All the same stuff, carrying information, just different frequencies.

Jill Tarter:

Let me illustrate what the universe looks like in these different wavelengths. It looks very different. We live in a galaxy that’s called the Milky Way Galaxy. If we could step out of our galaxy, which has about 400 billion stars, if we could step back and look at it from a distance, it would look something like this. This is our nearest neighbor galaxy called Andromeda, or M31 by the astronomers, and this is what that galaxy looks like if you use a big radio telescope, and you can see all the bright light there. Those are all stars shining, and there are a lot of stars at the center of the galaxy, so it’s very bright there.

Jill Tarter:

But what does that galaxy look like in the radio? What if your eyes could see radio? Well, if you looked at a particular frequency where hydrogen gas emits, that’s the same galaxy. It doesn’t look at all the same, does it? Because you’re looking at different things. You’re not looking at the bright stars. You’re looking at this neutral hydrogen gas, and hydrogen is the most abundant element in the universe, so it’s important to study hydrogen. And you can see that it’s dark in the middle, whereas back here, it was bright in the middle. The reason is that those bright hot stars ionize. They change the hydrogen neutral gas and you can’t see it. It isn’t there in the center because of the bright stars.

Jill Tarter:

So we learn a lot of different things about the universe by doing our observations in different wavelength bands, and in particular, we think the radio is a good place to look for engineered signals because radio waves travel throughout the galaxy. If you were a light ray or a radio ray, it would take you, traveling at the speed of light, a hundred thousand years to go from one end of the galaxy to the other, so that galaxy is about a hundred thousand light years across.

Jill Tarter:

I want to look at stars not in Andromeda. They’re very far away. Any kind of transmitter there would have to be incredibly strong if I were going to detect it. I want to look at stars in our own Milky Way. And in some directions on the sky when I look, there are stars in the Milky Way in the foreground. Here, okay? That’s Andromeda. We’re looking in that direction, but in our own Milky Way, those star symbols and the three white dots, those are stars that are like our sun very nearby, and I’d like to study those. So we’ve built a telescope that can do this at the same time. My astronomy colleagues can look at distant objects and I can look at nearby stars in the foreground.

Jill Tarter:

That telescope looks like this today. There are 42 small dishes that reflect radio waves, and we hooked them together with a lot of computing power as if they were one great big giant telescope. Now we have 42 today, we’re just hoping that someone will add money and it’ll grow to 350 because that’s our goal, but we’re using these telescopes today to do a search for extraterrestrial intelligence at radio frequencies. At the same time, the astronomers that I work with are studying the more distant universe in radio waves, and some of my colleagues are actually using optical telescopes looking for different kinds of signals.

Jill Tarter:

Now inside, if you were sort of to look under the hood of one of these telescopes, there’s this really strange looking device. It always reminds me of sort of early Buck Rogers … right? Death ray kinds of things, but that’s like the aerial on your car. The mirrors of the radio telescope focus the radiation down on this device, and we receive a very wide range of radio frequencies. But the big spiky things, they pick up longer radio waves, and the small spiky things, they pick up shorter radio waves, and we can observe all of these at the same time.

Jill Tarter:
Now, what in the world, I’ve been talking now for 10 minutes, what in the world am I talking for? What are we looking at? What would a signal, an engineered signal from someone else look like? Well, here’s a picture. There’s a signal in there. This picture is displaying frequency this way and time that way, and the signal that’s in that picture is coming from the most distant human object. It’s the Voyager One spacecraft that is now 106 times as far away from us as the sun is. It’s about to leave the Solar System and travel off into the interstellar medium. Have you found the signal yet? Ah, our computers have no trouble whatsoever finding that signal. Once we can tell a computer the kinds of patterns to look for, it can do a really good job at finding a pattern. So this is what an artificial signal would look like. What would sound like? What’s that? What is that? That’s actually noise. There’s nothing there. What about that? Can you hear it?

Jill Tarter:

That’s an artificial signal like this one. We don’t tend to use audio recordings or our ears to detect signals because we only are sensitive to a very small range of frequencies and there’s a lot of information that we want to cover. But I’ve already told you that when you can define what you want to look for in the noise, computers do a really good job. But what about signals that you can’t define yet? What about anomalous kinds of things you don’t know enough about them to program a computer to find them? Well, what’s good at finding patterns in noise. Well, you are. Your brain and your eyes particularly are really good pattern detectors. So we are starting a community that we call SETI Quest. So look us up at setiquest.org. We’re trying to find ways that a number of different individuals can participate in making the search better.

Jill Tarter:

And we can use you as citizen scientists to help us look at data and find anomalies that we’re not yet aware of. So I love the job that I do. And one of the things that excites me about doing this work is that I think even if we do not ever find a signal, SETI can change the world. Because the act of looking for intelligent signals from a distant technology opens up our horizons, makes us think about ourselves in a much larger environment, a more cosmic perspective. It holds up a mirror and says, “Hey, you. You there on Earth. You’re all the same.” I think the idea of thinking about whether there are technologies elsewhere helps to trivialize the differences among us, that we find so difficult to deal with. That’s why I get out of bed every morning. That’s why I work on SETI.

Jill Tarter:

So I’m going to end by showing you some images of the telescope as we hope it will become and as it is today, and I’d asked you to think about joining in this search, supporting it as a benefactor or as a citizen scientist, or as someone who’s eager to tell the story about looking for life elsewhere to your friends and getting them involved, because this may be a search that lasts for generations before it succeeds. And I am always in search of my replacement and the future generations to carry on this really cool job.

Jill Tarter:

Thank you.