IRA FLATOW, host:
And now a birthday greeting. Ten years ago, I talked with Dan Werthimer of the University of California at Berkeley about a new project that he had just begun, one that would let people lend their personal computers to help scientists hunt for signals from outer space. And in the 10 years since then, five-million SETI@home volunteers in over 200 countries have donated over three million years of computing time to the project. And while we have not heard that phone home from E.T. yet phoning us, in fact, the project has also sparked other distributed computing projects.
Dan Werthimer, chief scientist at SETI@home, joins us again today. Welcome back to the program.
Mr. DAN WERTHIMER (Chief Scientist, SETI@home): Thanks, Ira, pleased to be with you.
FLATOW: You must - are you getting impatient?
Mr. WERTHIMER: No, I think it's - we're in it for the long haul. It's going to be a while. Earthlings are just getting in the game. We've only had radio 100 years, and even though I'm really excited about all the searching that we're doing, I think we've only covered a small range of the possibilities. Radio signals could be going right by the planet, and we would miss them. We might get lucky, but I think it's going to be 50 or 100 years. So don't hold your breath.
FLATOW: What do you listen for? How do you know that it's something intelligent instead of just a star hissing or something?
Mr. WERTHIMER: So we're trying to answer this question: Are we alone? Is anybody out there? And the early ideas are that earthlings are sending off all this television and radio and SCIENCE FRIDAY, TALK OF THE NATION is going out at the speed of light, and you should be careful what you say, and the early Ed Sullivan, "I Love Lucy" shows have gone past 10,000 stars.
So maybe other civilizations have something like this, radio or television or radar signals that come off their planet or maybe just accidentally come off their planet the way that radio signals come off our planet. Or maybe even deliberately sending messages our way because they're interested in communication - that would be really spectacular. They might send us all their music, poetry, science, medicine, maybe tell us how to get on the galactic Internet and all the other civilizations they've been talking to.
So we're listening for these radio signals, and that's what we're trying to do, and that's what we're asking the volunteers around the world to help us analyze the data.
FLATOW: Do you use also some of those big radio telescopes like we saw in "Contact," you know, the very large array, things like that, or is it solely using the computing power of the SETI@home people.
Mr. WERTHIMER: Yeah, to do this work, we need a big telescope, and we need a big supercomputer, and we use the world's largest radio-telescope. It's called the Arecibo Telescope, run by the National Science Foundation. It's in Puerto Rico, and it was in the movie "Contact," and it was also in James Bond, "GoldenEye," although in "GoldenEye" it comes up out of the water. It doesn't really do that.
(Soundbite of laughter)
Mr. WERTHIMER: It's 1,000-feet across. It holds 10 billion bowls of Corn Flakes. It's a spectacular telescope, 10 times bigger than anything else on the planet. And we're able to use it, almost all year round, we're serving the sky with other groups…
Mr. WERTHIMER: …also serving the sky and collecting data, and then we send that data out to volunteers around the world.
FLATOW: Mm-hmm. And you're going to continue this project? Who funds it? Who's interested enough to give you the money for this?
Mr. WERTHIMER: Well, it was very difficult at first to raise the money. We started with volunteers doing the project - my colleague, David Anderson is a brilliant computer scientist and directs this project. In the beginning, we didn't have any money. And he did it - he had a full-time job. He did it as a volunteer. He wrote all this code. And now, people all around the planet are helping us analyze the data and helping us write the code.
We do have a little bit more money now that we, you know, we're more successful. We have money from the National Science Foundation. We have money from NASA. We have industry partners that help us with equipment that we need. And then we get funding from the volunteers. The participants send us money. So not only are they making the biggest super computer on the planet, but they're making it, the whole thing operate.
FLATOW: Why would we think that any civilization that hears us wants to talk to us? I mean, you know, we're smart enough to talk to them?
Mr. WERTHIMER: That's an interesting question. If they've been listening to our stuff or they've seen us evolve and they're seeing smog in our atmosphere, they might know, you know, they may have been watching us for a while, and there may be a kind of prime directive, don't mess with primitive civilizations like us. And maybe they're going to hold back until we stop killing each other. Or maybe they're just leaking signals. Maybe they don't care. They just leak off signals the way we do into space. Maybe they're interested in primitive civilizations like us. It's very hard - it's fun to speculate. It's really hard to know what's out there. And that's why we search…
Mr. WERTHIMER: …for a variety of signals. We don't really know what to look for. We're looking in - for laser signals, radio signals, lots of different kinds of signals. We have seven different searches here at Berkeley.
FLATOW: You know that Drake Equation, which was made famous by Carl Sagan, about how many civilizations that might be out there, a life in outer space, has been attacked recently as being very overly optimistic. Does that bother you guys at all?
Mr. WERTHIMER: You know, I think - again, this is one of these open questions. The Drake Equation is a kind of - there's a lot of speculation there. We don't really know what any of the numbers are. We know there's a trillion planets in our Milky Way galaxy.
If you'd asked me 15 years ago, are there planets in the Milky Way galaxy outside going around other stars? I'd say, well, we think so. We don't - but that's all changed now. We know about planets going around a lot of stars. We think there's a trillion planets. And our Milky Way galaxy alone has billions of galaxies.
Mr. WERTHIMER: So it will be incredibly bizarre, I think, if we were alone. But it's an interesting question either way. If we are alone, that's profound. If we're not alone, that's profound as well. So either way, I think this is an exciting question.
FLATOW: 1-800-989-8255 is our number. Talking with Dan Werthimer, director of the SETI program. How many people are involved with this? And how many computers - at home computers are working at any one time?
Mr. WERTHIMER: There are about a million computers working on this thing. The volunteers donate a couple thousand years of computing time every day. The people working on SETI@home and the other distributed computing projects have built the planet's biggest super computer on the planet. It does eight quadrillion calculations a second. That's eight petaflops. The largest - the second largest super computer is one petaflop, by comparison.
FLATOW: Mm-hmm. We're talking about SETI@home this hour on SCIENCE FRIDAY from NPR News.
I'm Ira Flatow talking with Dan Werthimer.
Let's go to the phones, to Dana(ph) in Yarmouth. Hi, Dana.
DANA (Caller): Hello.
FLATOW: Hi there.
DANA: Hi. And hello, Mr. Werthimer. Did I get the name right?
FLATOW: You got it right. Quickly, we're running out of time, Dana.
DANA: Okay. Yeah. Well, as an American citizen, I'm concerned that some intelligent life, ten, you know, thousand-plus light years from here now is going to pick up and embarrass us by picking up "I Love Lucy" signals and, you know, "American Idol" signals and other sorts of commercial dribble. And, you know, that's how they're going to perceive us by what they hear from, you know, commercial television all these years. It's kind of scary.
FLATOW: All right. Thanks for calling.
DANA: You're welcome.
FLATOW: Any comment?
Mr. WERTHIMER: Some people say we should transmit deliberately instead of leaking off all these strange signals. I actually think because we're a young civilization, we should not be transmitting deliberately. You know, maybe in a thousand years, if we don't hear anything, we should think about transmitting. But I think it's too early to do that.
We want to do passive searches. We want to be listening at first and try to understand what's out there. If we do transmit, it would be interesting to see - well, some people say we should transmit Bach and our best literature and science and poetry, put our best foot forward. Some people say it's better to just…
Mr. WERTHIMER: …put it all out there.
FLATOW: And do you have a plan for what if you do hear something intelligent?
Mr. WERTHIMER: Yeah. So the first thing is we want to make sure that it's really an interesting signal, that it's not a graduate student playing a prank on us or a bug in our software. And we - the way to do that is to ask a different group with a different telescope, different computing system, different instrumentation, different people, to look at it as well. And if they can see it and we can see it, maybe then ask other groups to see it and get it independently confirmed, then we'll know it's an interesting thing that should be pursued.
And at that point, we want to make the information public, all the information, everything we know, where to look, what frequency, what we know about the signal. And we might not know it's ET at that point. It might be - when pulsars were discovered, people thought they were ET, there was a new - so we might have discovered some new phenomenon. We'll say, hey, we don't know what this is. This new phenomenon might be another civilization. I imagine a lot of people start looking at it and try to figure out what it is.
And I think if it's sent to us deliberately, I suspect we'll be able to decode it, because they'll make it easy, you know, if they're interested in communication, they'll put lots of pictures, language lessons, they've probably been in contact with other civilizations, so they'll know how to do this.
If it's kind of a leakage thing, though, if it's sent accidentally, you know, kind of like we're trying to figure out what their television or their equivalent of SCIENCE FRIDAY, I think it's going to be very hard for us to figure out what's going on. So we'll know they're out there, but we won't know very much about them.
FLATOW: That's why we try to make the show as intelligent as possible.
Mr. WERTHIMER: And you do a great job, Ira.
(Soundbite of laughter)
FLATOW: So when those ancient civilizations - when Alpha Centauri picks us up or something, they'll know. And so, you're looking forward, you're feeling confident? May not in your - maybe not in our lifetime.
Mr. WERTHIMER: I think (unintelligible) the long run. I think, even though I'm really proud of what we're doing. I think there's this huge - we call it the cosmic haystack. We're looking for a needle in a haystack. We don't know where to point the telescope. We don't know what frequency to listen at. We don't know how powerful this signal is. We don't know what kind of signal, what kind of modulation and what kind of signal type it is. There's a huge number of unknowns in this search. And we're just getting aim, learning how to do this.
And the good news is that we're making incredible progress because it's limited by technology, how much computing power we have, the better - more computing power you have, the better job you can do looking for these signals. And that's a great kind of limit to have because that's growing exponentially. Capabilities of - in our group have been doubling every year.
Mr. WERTHIMER: And so, I'm actually optimistic in the long run that if our - if there are other civilizations out there, eventually earthlings will be able to get in touch with them and find out what's going on.
FLATOW: Well our limiting technology makes us say goodbye. Thank you very much for taking time to be with us today, Dan.
Mr. WERTHIMER: Thanks, Ira. And thanks for all the volunteers who are helping us.
FLATOW: We thank them too.
Dan Werthimer, director of the SETI program and the Center for Astronomy Signal Processing, associate director of the Berkeley Wireless Research Center, University of California, Berkeley.
I'm Ira Flatow. This is SCIENCE FRIDAY from NPR News.