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  • Is E.T. out there?

  • Well, I work at the SETI Institute.

  • That's almost my name, SETI.

  • "Search for Extraterrestrial Intelligence."

  • In other words, I look for aliens,

  • and when I tell people that at a cocktail party, they usually

  • look at me with a mildly incredulous look on their face.

  • I try to keep my own face somewhat dispassionate.

  • Now, a lot of people think that this is kind of idealistic,

  • ridiculous, maybe even hopeless,

  • but I just want to talk to you a little bit about why I think

  • that the job I have is actually a privilege, okay,

  • and give you a little bit of the motivation for my getting into

  • this line of work, if that's what you call it.

  • This thingwhoops, can we go back?

  • Hello, come in Earth. (Laughter)

  • There we go. All right.

  • This is Owens Valley Radio Observatory

  • behind the Sierra Nevadas, and in 1968,

  • I was working there collecting data for my thesis.

  • Now, it's kinda lonely, it's kinda tedious, just collecting data,

  • so I would amuse myself by taking photos at night

  • at the telescopes or even of myself,

  • because, you know, it, at night, I would be the only hominid

  • within about 30 miles.

  • So here are pictures of myself.

  • The observatory had just acquired at new book,

  • written by a Russian cosmologist

  • by the name of Joseph Shklovsky, and then expanded

  • and translated and edited by a little-known

  • Cornell astronomer by the name of Carl Sagan.

  • And I remember reading that book,

  • and at three in the morning I was reading this book

  • and it was explaining how the antennas I was using

  • to measure the spins of galaxies could also be used

  • to communicate, to send bits of information

  • from one star system to another.

  • Now, at three o'clock in the morning when you're all alone,

  • haven't had much sleep, that was a very romantic idea,

  • but it was that idea, the fact that you could in fact

  • prove that there's somebody out there

  • just using this same technology

  • that appealed to me so much that 20 years later I took a job

  • at the SETI Institute. Now, I have to say

  • that my memory is notoriously porous, and I've often

  • wondered whether there was any truth in this story,

  • or just, you know, misremembering something,

  • but I recently just blew up this old negative of mine,

  • and sure enough, there you can see

  • the Shklovsky and Sagan book underneath that

  • analog calculating device.

  • So it was true.

  • All right. Now, the idea for doing this, it wasn't very old

  • at the time that I made that photo.

  • The idea dates from 1960, when a young astronomer

  • by the name of Frank Drake used this antenna

  • in West Virginia, pointed it at a couple of nearby stars

  • in the hopes of eavesdropping on E.T.

  • Now, Frank didn't hear anything.

  • Actually it did, but it turned out to be the U.S. Air Force,

  • which doesn't count as extraterrestrial intelligence. (Laughter)

  • But Drake's idea here became very popular because it

  • was very appealingand I'll get back to that

  • and on the basis of this experiment, which didn't succeed,

  • we have been doing SETI ever since,

  • not continuously, but ever since.

  • We still haven't heard anything.

  • We still haven't heard anything.

  • In fact, we don't know about any life beyond Earth,

  • but I'm going to suggest to you that that's going to change

  • rather soon, and part of the reason, in fact,

  • the majority of the reason why I think that's going to change

  • is that the equipment's getting better.

  • This is the Allen Telescope Array, about 350 miles

  • from whatever seat you're in right now.

  • This is something that we're using today

  • to search for E.T., and the electronics have gotten

  • very much better too.

  • This is Frank Drake's electronics in 1960.

  • This is the Allen Telescope Array electronics today.

  • Some pundit with too much time on his hands

  • has reckoned that the new experiments are approximately

  • a hundred trillion times better than they were in 1960,

  • 100 trillion times better.

  • That's a degree of an improvement that would look good

  • on your report card, okay? (Laughter)

  • But something that's not appreciated by the public is,

  • in fact, that the experiment continues to get better,

  • and, consequently, tends to get faster.

  • This is a little plot, and every time you show a plot,

  • you lose 10 percent of the audience. (Laughter)

  • I have 12 of these. (Laughter)

  • But what I plotted here is just some metric

  • that shows how fast we're searching.

  • In other words, we're looking for a needle in a haystack.

  • We know how big the haystack is. It's the galaxy.

  • But we're going through the haystack no longer

  • with a teaspoon but with a skip loader,

  • because of this increase in speed.

  • In fact, those of you who are still conscious

  • and mathematically, you know, competent,

  • will note that this is a semi-log plot.

  • In other words, the rate of increase is exponential.

  • It's exponentially improving. Now, exponential is an

  • overworked word. You hear it on the media all the time.

  • They don't really know what exponential means,

  • but this is exponential. (Laughter)

  • In fact, it's doubling every 18 months, and, of course,

  • every card-carrying member of the digerati knows

  • that that's Moore's Law.

  • So this means that over the course of the next

  • two dozen years, we'll be able to look at a million star systems,

  • a million star systems, looking for signals

  • that would prove somebody's out there.

  • Well, a million star systems, is that interesting?

  • I mean, how many of those star systems have planets?

  • And the facts are, we didn't know the answer to that

  • even as recently as 15 years ago, and in fact, we really

  • didn't even know it even as recently as six months ago.

  • But now we do. Recent results suggest

  • that virtually every star has planets, and more than one.

  • They're like, you know, kittens. You get a litter.

  • You don't get one kitten. You get a bunch, okay. (Laughter)

  • So in fact, this is a pretty accurate estimate

  • of the number of planets in our galaxy,

  • just in our galaxy, by the way,

  • and I remind the non-astronomy majors among you

  • that our galaxy is only one of a hundred billion

  • that we can see with our telescopes.

  • That's a lot of real estate, but of course,

  • most of these planets are going to be kind of worthless,

  • like, you know, Mercury, or Neptune.

  • Neptune's probably not very big in your life. Okay.

  • So the question is, what fraction of these planets

  • are actually suitable for life?

  • We don't know the answer to that either,

  • but we will learn that answer this year, thanks to

  • NASA's Kepler Space Telescope,

  • and in fact, the smart money, which is to say the people who work on this project,

  • the smart money is suggesting that the fraction of planets

  • that might be suitable for life is maybe one in a thousand,

  • one in a hundred, something like that.

  • Well, even taking the pessimistic estimate, that it's

  • one in a thousand, that means that there are

  • at least a billion cousins of the earth

  • just in our own galaxy.

  • Okay, now I've given you a lot of numbers here,

  • but they're mostly big numbers, okay, so, you know,

  • keep that in mind. There's plenty of real estate,

  • plenty of real estate in the universe,

  • and if we're the only bit of real estate in which there's

  • some interesting occupants, that makes you a miracle,

  • and I know you like to think you're a miracle,

  • but if you do science, you learn rather quickly that

  • every time you think you're a miracle, you're wrong,

  • so probably not the case.

  • All right, so the bottom line is this.

  • Because of the increase in speed, and because of the

  • vast amount of habitable real estate in the cosmos, I figure

  • we're going to pick up a signal within two dozen years, and

  • I feel strongly enough about that to make a bet with you:

  • either we're going to find E.T. in the next two dozen years,

  • or I'll buy you a cup of coffee. (Laughter) Okay.

  • So that's not so bad. I mean, even with two dozen years,

  • you open up your browser and there's news of a signal,

  • or you get a cup of coffee.

  • Now, let me tell you about some aspect of this that

  • people don't think about, and that is,

  • what happens? Suppose that what I say is true.

  • I mean, who knows, but suppose it happens.

  • Suppose sometime in the next two dozen years

  • we pick up a faint line that tells us

  • we have some cosmic company.

  • What is the effect? What's the consequence?

  • Now, I might be at ground zero for this.

  • I happen to know what the consequence for me would be,

  • because we've had false alarms. This is 1997,

  • and this is a photo I made at about 3 o'clock in the morning

  • in Mountain View here, when we were watching

  • the computer monitors because we had picked up a signal

  • that we thought, "This is the real deal." All right?

  • And I kept waiting for the Men In Black to show up. Right?

  • I kept waiting for, I kept waiting for my mom to call,

  • somebody to call, the government to call. Nobody called.

  • Nobody called. I was so nervous

  • that I couldn't sit down. I just wandered around

  • taking photos like this one, just for something to do.

  • Well, at 9:30 in the morning, with my head down

  • on my desk because I obviously hadn't slept all night,

  • the phone rings and it's the New York Times.

  • And I think there's a lesson in that, and that lesson is

  • that if we pick up a signal, the media, the media will be on it

  • faster than a weasel on ball bearings. It's going to be fast.

  • Okay, you can be sure of that. No secrecy. Okay?

  • That's what happens to me. It kind of ruins my whole week,

  • because whatever I've got planned that week is kind of out the window.

  • But what about you? What's it going to do to you?

  • And the answer is that we don't know the answer.

  • We don't know what that's going to do to you, not

  • in the long term, and not even very much in the short term.

  • I mean, that would be a bit like

  • asking Chris Columbus in 1491, "Hey Chris,

  • you know, what happens if it turns out that there's a

  • continent between here and Japan, where you're sailing to,

  • what will be the consequences for humanity

  • if that turns out to be the case?"

  • And I think Chris would probably offer you some answer

  • that you might not have understood, but it probably

  • wouldn't have been right, and I think that to predict

  • what finding E.T.'s going to mean,

  • we can't predict that either.

  • But here are a couple things I can say.

  • To begin with, it's going to be a society that's way in advance of our own.

  • You're not going to hear from alien Neanderthals.

  • They're not building transmitters.

  • They're going to be ahead of us, maybe by a few thousand

  • years, maybe by a few millions years, but substantially

  • ahead of us, and that means, if you can understand

  • anything that they're going to say, then you might be able

  • to short-circuit history by getting information from a society

  • that's way beyond our own.

  • Now, you might find that a bit hyperbolic, and maybe it is,

  • but nonetheless, it's conceivable that this will happen,

  • and, you know, you could consider this like, I don't know,

  • giving Julius Caesar English lessons and the key

  • to the library of Congress.

  • It would change his day, all right? (Laughter)

  • That's one thing. Another thing that's for sure

  • going to happen is that it will calibrate us.

  • We will know that we're not that miracle, right,

  • that we're just another duck in a row,

  • we're not the only kids on the block, and I think that that's

  • philosophically a very profound thing to learn.

  • We're not a miracle, okay?

  • The third thing that it might tell you is somewhat vague,

  • but I think interesting and important,

  • and that is, if you find a signal coming from a more

  • advanced society, because they will be,

  • that will tell you something about our own possibilities,