MARY LOUISE KELLY, HOST:
Astrophysicist Adam Frank is bouncing in his seat. He is that excited to be at a NASA conference in Houston - a NASA conference all about looking for signs of civilization somewhere far beyond Earth. This sort of meeting has not happened in decades, so we've got Adam on the line to tell us all about it. Hey there.
ADAM FRANK: Hey, how's it going?
KELLY: Well, thank you. So why hasn't this kind of meeting happened in decades, and why now?
FRANK: Well, in the 1990s, NASA was - had a project for doing search for extraterrestrial intelligence, or SETI. And it turned out that some people in Congress thought it was a giant waste of taxpayer dollars. But since then, you know, researchers - there was sort of the sense that NASA was not the place to do SETI. And so even though NASA has done amazing work in searching for life, it has really not done much about searching for intelligent life.
KELLY: So you're at a NASA conference now, though, and they are searching for signs of extraterrestrial life. That's the focus of this conference?
FRANK: Yeah. Well, really what they're looking to do is they're looking for help, suggestions in terms of looking for technosignatures.
KELLY: What's a technosignature?
FRANK: A technosignature is basically any signal or evidence you can find that there is a technology-using civilization out there. So we have been talking about things for the last couple days like looking for pollution in the atmosphere of a distant planet. We've talked about detecting satellites - their satellites in orbit. We've even talked about the ability to see cities on distant planets because of their heat signature. So it's really all amazing stuff, and we're really getting to the point where some of this is going to be possible now, or it is going to be possible in the near future.
KELLY: For the record, have they found anything?
FRANK: No. We have not found anything yet. But the important thing to understand is that, you know, people have this idea that, like, SETI's happening all the time, that astronomers are always looking for civilizations among the stars. And it's actually not true. One of the talks that was given was by a researcher who actually looked at how much searching we've done, and it turns out that if the stars were, like, at the ocean, then the only thing that we've looked at so far is a hot tub (laughter).
KELLY: Because there's just so - it's so big. There's so much to look at.
FRANK: There's so much to look at. And we've done so little of it so far. So if you're interested in whether or not there are dolphins in the ocean and you've looked at one hot tub and you didn't find a dolphin, would you then say like, oh, there's no dolphins in the ocean?
KELLY: You're making the case for optimists. The fact that they haven't found anything yet by no means rules out that it's out there and could be found.
FRANK: That's true. What has really changed now is the discovery of exoplanets - that we've found all these planets orbiting other stars whereas, 20 years ago, we didn't know whether there were any planets orbiting any other stars. And that changes the whole nature of how we go about looking for them.
KELLY: It raises all kinds of possibilities in terms of places to look.
FRANK: That's it and that we're finally actually able to stare at planets, which is where we think life forms. And if you look at the history of SETI, originally taking a radio telescope and looking for someone beaming messages to you - right? - an intentional signal, and now with these exoplanets that we're staring at, we can look for unintentional signal, things like pollution or satellites in orbit. And that really changes the game. It's not your grandparents' SETI anymore.
KELLY: Thank you, Adam.
FRANK: Oh, it so much fun. Thank you.
KELLY: Adam Frank - he teaches astrophysics at the University of Rochester. His most recent book is "Light Of The Stars: Alien Worlds And The Fate Of The Earth."
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