December 7, 2021 • 43 mins
Daniel talks to Jill Tarter, longtime head of the SETI program, about how to look for alien intelligence
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Speaker 1 (00:00):
Hi, it's Jorge and Daniel here. And this holiday season,
if you're looking for a gift for yourself, for a friend,
or for your your family, why not get him the
gift of Answers about the Universe. So check out our
new book Frequently Ask Questions about the Universe. You can
find details at universe f a q dot com. Thanks
for supporting the podcast. Happy holidays everyone. How much have
(00:31):
you thought about what it might be like to talk
to aliens? While biologists wonder about what form alien life
might take, linguists speculate about how we might communicate with them,
and conspiracy theorists wonder whether aliens have already visited Earth
and taken over our government. Physicists have long expressed confidence
that they could most easily find common ground with aliens,
(00:53):
assuming that math and physics are universal, not specific to
Earth biology. Even more than that, physicists practically salivate at
the prospect of learning from aliens answers to big questions
in physics, how to bend space and time, or crack
open black holes and play elaborate pranks on Navy pilots.
But what would it actually be like to try to
(01:14):
learn physics from aliens. Could we even understand the cosmic
secrets they might share with us? Would they be so
advanced it would be like Schrodinger explaining quantum mechanics to
its cat. Do we actually share math and physics with
every intelligent civilization out there? Or would their minds be
so alien it would just be impossible. Hi, I'm Daniel.
(01:49):
I'm a particle physicist, and I can't wait to talk
to the aliens and learn the secrets of the universe.
There are so many things we don't understand about the universe,
and if aliens visit it or managed to send us
a message, it seems likely that they might have been
working on these questions for thousands or millions, or even
billions of years. Imagine catapulting our understanding that far forward.
(02:12):
We might learn about how quantum mechanics really works, or
what's inside a black hole, or how the universe actually began.
But is that making a basic mistake? Assuming the humans
and aliens might think about science in the same way,
how could we possibly anticipate what aliens might know, or
think about or wonder at so Welcome to the podcast.
Daniel and Jorge explain the universe of production of I
(02:35):
Heart Media, in which we dive deep into all these
questions about the universe. We asked the biggest, the deepest,
the craziest questions, and we strain for answers, explaining to
you everything we understand and everything that we don't. My
friend and co host Jorge is on a break, but
I have a special treat for you today. We are
very lucky to have as a guest one of the
leading scholars in the field of the search for extraterrestrial intelligence.
(02:59):
Today we'll be talking to Jill Tarter, astronomer and longtime
chair of the SETI program, the Search for Extra Terrestrial Intelligence,
and so today on the program, we'll be asking the
question how should we be searching for extra terrestrial life?
(03:20):
So it's my great pleasure to introduce Dr Jill Tarter.
She's very well known for leading the SETI program for
many years and is also famous for introducing the phrase
brown dwarf in her pH d thesis, which she completed
at Berkeley nine. But she's also been a leading voice
in the search for extra terrestrial life and intelligence for
more than three decades and has won many awards, including
(03:40):
the Carl Sagan Prize for Science popularization and being elected
to the American Academy of Arts and Sciences. Dr Tarter,
Welcome to the podcast. Thank you for joining us, Thank
you for having me. Daniel. So, I actually dug into
your thesis a little bit and I thought it was
quite fascinating. But it's well. I actually also got my
PhD from Berkeley the several years later, and I was
(04:01):
curious reading through it. It's not obvious the direction of
your career would take. So how did you get into
the search for extraterrestrial intelligence? Like what set you on
that course? Well, it all had to do with Berkeley
and graduate school and it was a big accident. So
my first year at Berkeley, I was supported on our
research assistant ship to program the first computer that we
(04:25):
ever had on our desktop. So it was a PDP
eight slash s now took two people to get it
on the desktop, so it wasn't that small. But the
other thing about it was that it had no language,
so you had to program the whole thing in often
for every instruction you wanted it to do, you had
to set all the ones in zeros. Kind of a
(04:47):
pretty arcane skill, but I found it interesting and fun,
so I did that for a year, and then I
went on to other things. Finally, many years later, when
I was about to finish my PhD and go off
to a post dog, Stu Bowyer, an X ray astronomer,
had a really clever idea. He'd been reading the material
(05:08):
that had been put out by NASA aims on the
search for life beyond Earth, and he said, you know,
UC Berkeley has a radio telescope in northern California, and
he was clever enough to know that with a radio
telescope you can make essentially a noiseless copy of the
voltage coming out of the telescope, and then on your
(05:32):
copy you could process it looking for engineered signals while
the astronomers went ahead and did whatever they were going
to do anyway, So very clever, this idea of observing commensally.
But he had no money, so he went begging for
pieces of equipment, and somebody gave him a hundred channel
p AR auto car. Later, and somebody else gave him
(05:54):
this old p d P A S computer. So somebody
pointed out to Stu that I used to work on
that computer, and he showed up in my office one
afternoon with a copy of the cyclops report that had
been done at NASA, Ames saying the way to find
extraterrestrial intelligence was to build an array of six hundred
(06:15):
meter telescopes. That never happened, but anyway, he gave me
that as a recruiting tool, and I read it and
I just got really hooked. Here I was with potentially
the right skills, in the right place, at the right
time to perhaps make a contribution to answering this age
old question of are we alone? So I worked with
(06:39):
the PDP eight s again and got a program with
Stu up and running at that creek, and then, you know,
as I said, I was hooked, and I've stayed hooked
ever since. It amazes me how we sometimes see sciences
as like linear, natural, obvious progression, but so much of
it depends on random accidents. Who happens to talk to
(07:01):
who and be inspired by what? And if you ran
the Earth science a hundred times in, you know, with
different initial conditions, you might get completely different trajectories of intellectually,
like where we end up as a species. So you
mentioned this, the device that wasn't built. What is SETI
actually doing? What instruments are they using and operating and
what are they actually listening for right now? Well, set
(07:23):
the search for extraterrestrial intelligence, which is a misnomer because
we don't know how to find intelligence, per say, we
can't even define it um. What we're doing is trying
to find evidence that somebody else is using some technology
that we can discover over the vast distances between the stars.
(07:45):
And so it started out as using radio telescopes to
try and find engineered signals, and then over time we
expanded it into optical searches and infrared searches, and now
we are trying to do something that we've known that
(08:06):
we should be doing for the past twenty years, but
just haven't had the technology to do it, and that
is to look for transient signals. And the trick there
is you want to look at all the sky, all
the time, and at as many frequencies as you possibly can.
And so now we are finally able to build starting
(08:28):
in the optical and then moving into the radio telescopes
that look at tens of thousands of square degrees at
a time, and in one case, if we can complete
the instrumentation, all the sky all the time looking for
these transient signals. So that's the exciting frontier for CET
today to try and get this sky coverage. And the
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other exciting thing is to begin to look at the
data in a different way. Historically, we have always looked
at data and said, is there a signal of this
description in the data, And we have defined the signals
that we're interested in as being frequency compressed in the radio,
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or time compressed in the optical, or monochromatic lasers in
the optical. But now we're beginning to see if we
can use machine learning to help us find patterns of
any kind in the data without having to pre describe
what pattern we're looking for. So we're hoping that algorithms
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in the future will be able to look at data
voltage is a function of time, intensity is a function
of time and say there's information content here, or no,
this is all noise. That's fascinating. If we need artificial
intelligence to recognize alien intelligence, well that alien intelligence is
quite likely to be artificial itself by machines, So maybe
(10:01):
we need machines as interpreters. But still we need to
somehow train that machine learning. We need to teach it
the kind of things that we are looking for. We
can't just we're not raising generic intelligence and say go
out and find some aliens, right, doesn't there need to
be some fought in advance for the kinds of things
we're teaching our machine learning algorithms to find. Well, actually,
(10:21):
the real problem is how do you get a null set?
How do you give it data that you know has
no information content. You know, when you have a data
set and we've explored it for X, Y and Z,
it doesn't mean that Q isn't there. So generally to
get a null set you generated randomly on a computer,
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and then you can give it lots of examples of
different signals that we have detected or that we generate
ourselves as the counter. And again it's early days. We're
very hopeful and we'll see what happens. Right. I suppose
you can't just take the ABC from the sky and
say assume there's nothing here, because the whole point is
to look for data in the sky, so then it
(11:06):
would learn to ignore signalities there. So you mentioned something fascinating,
which is thinking about the messages that we would send
or the ones that we have sent, and know that
in the early days of space exploration, you know, for example,
there's a Golden Record. We put on some of our probes,
and there's a message we sent out via a Recibo.
How do you look at those messages that we've sent
sort of with modern eyes, How would you design a
(11:28):
message to generic aliens now you hope would be observable
and detectable to the broadest set of intelligence. Well, I
do something that we haven't done with the Acibo message
or any of the other messages that we've transmitted, and
that is I would do it for ten thousand years,
all right. If you send a finite transmission, then that
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message is going to go past your target in a
finite amount of time, and the receivers would have to
be looking at you at just the right time, in
just the right way as your message flies past in
order to detect it. And the probability of that is
pretty small. So I think what you want to do
is start transmitting and then don't stop right so that
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whenever an emerging technology wakes up and begins to explore
its environment, your signal will be there for them to
find when and if they develop the right technologies and
the right strategy and are motivated to be looking. So
that's I think what I would do. And the reason
(12:36):
that I'm not at all enamored of efforts to transmit
messages today because we're just not grown up enough to
be able to culturally be able to manage such a
long term project. It's like just shouting once in the
night and hoping that somebody hears. You know, it's fascinating
as our message sort of sweeps across the universe. It's
always somewhere, but the chances that it happens to arrive
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when some he's listening do seem pretty small. Do you
think that's something our civilization would ever be capable of
sending messages for tens of thousands of years? Do you
think our civilization will last long enough to be able
to do that? I hope so. And in fact, one
of the things that I think about is that suppose
the distribution of lifetimes of technological civilizations or technologies, because
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that's what we're going to find is the technology is bimodal,
So you have lots of short lived technologies. They emerge,
develop an either turn themselves off or do themselves in.
They don't have a very long lifetime when compared to
the ten billion year history of the Milky Way, galaxy.
But now there might be an addition, some very long
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lived civilizations, And it might be that the probability of
transitioning from short lived technology to a long lived technology
is dependent on discovering other technological civilizations that have made
(14:07):
it to an old age. And I think that's one
of the things that today motivates me to continue working
on this project. How can we have a long future
for life on this planet? And if so, how and
that the answer to me is if anybody else has
made it through, that means we can figure it out too.
(14:29):
Are you suggesting that discovering a longstanding alien civilization might
help us build a civilization that's long standing just knowing
that it's possible. I think that's not unlikely or not impossible.
If I know that there's a solution to a problem,
even if I can't figure it out right now, I
have more motivation to figure out the solution. I know
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it's possible, So how the heck am I going to
solve it? That's very insporational. I hope that's true. In
all of these searches were looking for signals, signals generated
by technologies which in the end are somewhat similar to ours.
And there seems to be an implicit assumption there that
you know their information, their messages will be encoded in
(15:13):
ways that are familiar to us, even if the actual
code is alien. The fact that they are sending messages
coded in electromagnetic radiation of some kind assumes that you
know the civilization is mathematical or scientific. Do you think
that it's possible for us to imagine aliens in a
more broad sense, you know, to think about aliens that
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might not do math or might not have a scientific exploration,
or do you think that we can only search for
aliens that are sort of similar to us intellectually that
we could ever communicate with them. Well, they're kind of
two pieces to that question. One, we have a certain
amount of technology in the twenty one century, and we
understand a certain subset of physics, and those are the
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tools we have. We can't use tools that we don't have.
We can't search for things that we don't yet understand.
And in terms of another technology, we're actually trying to
think more broadly than we originally did, So not just
radio signals or not just optical signals, but something that
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we call a techno signature, something that is the result
of someone doing something with technology out there. And it's
particularly important to think about that now because we're moving
from the generation of ten class optical instruments and a
(16:42):
hundred elements in inferometers two thirty forty telescopes and interferometers
like near Cat the square kilometer array that are going
to have thousands of elements. So our ability to see
things on the sky is going to improve dramatically, and
(17:04):
we want to be thinking about, oh, what's that and
how the what's that might be interpreted in terms of technology,
So we're thinking about signals that are almost natural or
things that are obviously engineered. And obviously engineered has been
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the piece that we've been doing us far. But when
you begin to think about almost natural, you think about
maybe a pulsar, right, which has a period it's very constant,
and then it changes its period. Now we've seen that
in the data because there are star quakes on these
neutron stars have changed the moment of inertia and change
(17:45):
the period of the pulse sar. But what we haven't
seen is a pulsar that starts at one period, changes
to a second period, and then goes back to the
first period. But those could well be in our data
sets as we searched the sky for pulsars, So it's
almost natural, and we would catch it in a net
(18:06):
when we're doing an astronomy survey. So another example I
like to think about is transit. So we've been finding
all these exoplanets because they cast a shadow on the
image of the star and change the stellar luminosity as
the planet transits in front of the star. Now, the
(18:26):
i AU has declared that planets are spherical, right, and
so their shadows are going to be circular. But what
about some giant constructed artifact that's like a Venetian blind
or a triangle. Well, in the higher order moments of
the light curve at ingress and egress, you could tell
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the difference if you looked hard enough, between a triangular
shadow and a circular shadow. So that might be an
almost natural signal that would in fact ultimately lead us
to technology. Wow. Fascinating. So we have a whole spectrum
of things which we classify as natural because we think
(19:12):
they're not the product of intelligent action. Things are clearly artificial,
like the signal that says hello, we got your air
cebra message. Here's our address, and now you're imagining things
in between, which are subtle evidence of deviations from sort
of natural evolution of the universe because of intelligent actions.
You know, we're going to have so many new and
(19:32):
different eyes on the cosmos that we ought to be
broadening our thinking. That's fascinating and it seems like a
very worthwhile It still seems to me to be indicative
of sort of the way that our minds work. You know,
we build things that are square, and we build things
that are symmetric, and we're imagining that maybe aliens could
do that as well. And I certainly take your point
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that we can't look for things that we don't understand,
and we can't look for things that we can't imagine.
Does that frustrate you that you know that might be
that the spectrum of intelligence aliens out there could be
so much broader than we can imagine that it might
make it impossible to ever discover them. Yeah. Well, for
the longest time, we said, okay, if they have some
technology that we might be able to detect in some fashion,
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they're going to have to have math, right, can't build
things without some artificial way to represent them and construct them,
And so we thought, okay, so that means math is
the universal language of the cosmos. And then we had
some really interesting talks at the Cutty Institute by people
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who study the human brain, and they pointed out that, yeah,
they might well have math and be representing exactly the
same things that are mathematical programs do, but that our
math and the way we represent things is inevitably shape
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by the nature and structure of our human brain. And
so they might well be talking about exactly the same thing,
the same mathematics, but the representation of it might be
so different that we don't recognize it as such. So
now that's so are right now. And if you look
back at the sort of history of the development of
(21:23):
mathematics and the philosophy of mathematics, you know there are
still like big open questions about how to even build
a mathematical system that's self consistent, and a lot of
mathematicians practicing mathematicians sort of ignore that and say, look,
we have a system that mostly works. We can get
stuff done. But it tells you that if human history
had gone another way, if a different philosopher had been
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born or been influential, we might all think very differently mathematically,
And so the spectrum of like possible human explorations of
you know, ways to think is so potentially broad, and
it's sort of terrifying to imagine how broad it might
be when you're including, yeah, well there are anthropologists who
tell us that there are some very isolated tribal groups
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that don't have a zero in their worldview. So you
can do what you can do, and you can't do
what you can't yet do. So you've been working on
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this for a while. How long do you expect that
this project might take? I mean when LEGO turned on,
for example, I remember thinking, well, they have no idea
how common gravitational waves are, and they had no clue
whether they would wait decades for the first signal, And
of course they were lucky they heard something almost immediately,
and it's been a treasure trove. Do you harbor such
hopes that, you know, if we expand our capabilities to
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listen to the sky, that we might learn something too.
I don't know about soon. I think this could well
be a multi generation all exploration. And the reason I
say that is that the volume that might need to
be searched, even if an electromagnetic signal is the right
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thing to be looking for. That volume is really vast,
and so when c turned fifty, I tried to do
calculation that would show how vast it was and how
much we had searched to date for an electromagnetic signal. Again,
assuming that's the right thing to be looking for, there
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are nine different parameters that you have to explore space
and time and polarization and modulation and intensity, all of us.
And so I tried to make a guess at what
the range of each of those parameters might be, and
then I multiplied them all together some sort of a
nine dimensional volume. And I'm not any good at visualizing
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nine dimensional volumes. So I said, okay, here's the analogy
that volume. I'm going to set it equal to the
volume of all the Earth's oceans and then ask how
much of the Earth's oceans have we searched in fifty years.
And at that time the answer was one glass of
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water out of the ocean. Right. That shows you how
vast the search might need to be. And then when
city turned sixty, ten years later, the students at Penn State,
we did the calculation and they said, it's not a glass,
it's more like a small swimming pool, so that was
a big improvement over ten years, but still not a
(24:39):
lot of the oceans. So I think that it might
be multi generational, either because we haven't yet invented the
right technology, we don't understand the physics that's involved, or
simply because the search is so vast it's going to
take a while. It's getting faster all the time, primarily
(25:02):
because of Moore's law and the improvements in our computational capabilities,
but it may have to go on for a while.
The exciting thing for me about research like that is
that you just don't know until you begin if you're
searching for a signal which is obvious or really subtle.
Like in your ocean analogy, you only need a glass
of water to find salt, right, but if you're looking
(25:22):
for a particular fish, you may have to look through
millions and millions of glasses. And in our case, we
just don't know right how many civilizations are out there
they're super rare, or if they're everywhere. So have your
hope sort of changed over the years that when you
first got involved in this, in your that first project
you described using the PDP, did you think I might
discover aliens tomorrow. If your hopes sort of kept up
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or have they dimmed over the decades, well that's still true.
We could discover something tomorrow, or it might be my
granddaughter's generation that succeeds. We don't know, And this is
one of those questions that you don't know the answer
until you find the answer. And if anybody you know,
if I told you anything different, right, that would be
(26:07):
religion and not science. So no one knows. I still
think it's worthwhile. Humans have been asking themselves this question
since we walked out of the caves. We're really intrigued
with how we fit into the cosmos, how we compare
something else that might be out there. So every day
(26:29):
you're looking at information could be the day that you
get the signal that says wow. And now, like human
history pivots on that point, before that moment and after
that moment. So in your career or in the decades
of that we've been doing this, have there been any
moments when you thought to yourself, this could be any
sort of like, oh, this looks real kind of moments. Yeah,
there have been a few, and they've all turned out
(26:51):
to be false positives. But some of them took a
lot longer to dismiss than others. Let's see, we usually
observe with two widely spaced telescopes, and we require that
the signal be found at both and that it had
(27:14):
the appropriate light travel time between them, and that it
have if it's a narrowband signal, we can require that
it have a differential Doppler signature that represents the Earth's rotation. Right,
So we have all these tests that we need to do.
But back in nineteen I think it was, we were
(27:36):
using a telescope in green Banquest, Virginia and another one
in Woodbury, Georgia, and lightning struck the telescope in Georgia
and went through the electronics and frieda district, so that
telescope was off the air for days before FedEx could
get a new dis drive into the facility. But we
(27:57):
still had time. And that's of course a very racious
thing on the telescope in green Bank, West Virginia. So
we kept observing with that one telescope in a manner
that radio astronomers have often used. They stare at a
target source and then they look away, and then they
go back and they differentiate between the on and the
(28:20):
off source. So we we tried that with the Green
Bank telescope and sort of like five o'clock in the morning,
I saw a signal that was clearly artificial. Looked in
this waterfall plot, as we call it, like a picket fence.
So I saw multiple frequencies lit up, and the spacing
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between those frequency features was constant. That's not another nature.
And so I saw this every time I looked at
the target that we were tracking, and every time we
pointed the telescope away from that target, it went away.
And this went on for a while, and then I
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finally got clever idea. I said, okay, we've been observing
here for a couple of weeks. Let me look through
all the data that we have taken when looking at
other parts of the sky and see if we've ever
seen a signal that has that frequency spacing. Right, that's
a very significant characteristic. And so I wrote a program
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and it actually compiled me and I ran it, but
I was in I was excited. I mean I was
really excited, and so I was sloppy with my output,
and when I looked at the output, I actually missed
the fact that, yes, we've seen that particular signature when
looking in other places on the sky, but you know,
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being excited and I dismissed it. So we continued tracking
that and I woke up my colleagues, got them to help,
and finally, as the source set in the west, the
change in the drift rate that changed with frequency and
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time of the signal was consistent with something that was
rising to the zenith, not setting on the horizon, and
so sadly, by the end of the afternoon we knew
that this wasn't a real extraterrestrial signal. We didn't know
(30:29):
what it was. It took a while of doing web
searches and it turned out it was the Soho spacecraft
in orbit, not around the Earth we would have caught
that much earlier, but around the sun. And telescopes, like
human eyes, which have peripheral vision, telescopes have sidelobes where
(30:53):
the sensitivity is much lower, but it's not zero, And
so every time I pointed at the target, the Sun
would be in the sidelo, and when I moved the
telescope to the different direction, the sun fell out of
that silo and the sun tracked the Earth's rotation just
as the target ten, and so it took us a
(31:13):
while to figure that one out, but it was exciting.
It was really an enormous amount of adrenaline, and then
disappointing when we figured it out and we figured out
a couple of different ways to avoid having that happened
to us again well as a fascinating moment, because on
one hand, you desperately want to believe it's sort of
(31:33):
your scientific fantasy. On the other hand, you want to
push on it as hard as possible because you definitely
don't want to announce something if it's not real, and
so you have to be like the biggest cheerleader and
also be the biggest skeptic at the same time. Yeah,
make me a liar exactly. So what would happen and
(32:04):
walk us through what would happen if you got a
signal and you were not able to identify as coming
from any satellite or any nearby object, and all the
evidence pointed to it coming from another star and it
seemed sincerely artificial. Is there you know, a real protocol
sort of politically for what happens in that scenario? Do
you have to contact US government or are you're allowed
to talk to scientists from other countries about it. Well,
(32:26):
when we were ann asked the project, Yeah, there was
a protocol and it included which associate administrator was going
to notify in the White House, right, and it was
that detail. Now that we are philanthropically privately funded and
the other SETI projects like break through Lists and are
also privately funded, there is a protocol that we've informally
(32:49):
agreed upon. It has no enforceability, but basically it says,
at the discovery site, you try and use another instrument
now that you know what you're looking for. Probably a
normal off the shelf Hewlett Packard spectrometer will allow you
to find that signal. So you try and just detected
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with instrumentation that you didn't build and software that you
didn't write as a confirmation. And then if you do
that and you have some more confidence, then indeed you
do quietly call up the director of some observatory to
the west and ask for a little bit of discretionary
(33:32):
time to see, knowing what they're looking for, if they
can detect the signal, and that's probably your best hedge
against a hoax and deliberate hopes. And then if you
get that independent confirmation, then you sit down and figure
out how you're going to tell the world. And one
of the things that you might consider doing is sending
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out what used to be called an I A U telegraph,
something that goes to all the observatories around the world,
discreetly telling them what you've found and prepping them for
the fact that there will be a press conference coming
up very quickly, because what you want to do is
train up a bunch of professionals who can interpret for
(34:18):
their local media what's actually been found, and not leave
the media to make it up for themselves, right, because
it's probably going to be maybe ambiguous, right, and you
don't want the media writing their own story, so you'd
like to give them as much assistance in understanding what's
(34:40):
really been discovered. And then you tell the world, and
you want to be very careful that you make sure
that everyone who's been involved in any way gets appropriate credit.
Then you hope that the network at the study institute
or wherever the discovery site is doesn't melt from the
world trying to get hold of you, and you see
(35:00):
what happens. So walk through a hypothetical best case scenario.
Say we see an artificial signal and other people confirm it,
and we believe that it's there, then what do we do?
Do we respond? Do you write a message back and
you spend a decade trying to decode it, understand the
contents of it, and debate how to respond. Did we
spend you know, a hundred years going back and forth
(35:20):
before we learn each other's language and understand each other's mathematics. Oh,
we've thought about it, and we've held workshops and basically,
should we respond? And if so, who will speak for Earth?
And what will they say? And I think the disappointing
thing for me at the moment is so we've held
a number of workshops, they haven't really involved very much
(35:43):
of the world's diverse cultures. It's been sort of pretty
waspy and pretty male. So we continue to think about this,
and I continue to try and find a way two
take this question globally and find appropriate venues to ask
other cultures in other ways of being and thinking what
(36:07):
they would do, how they feel. So it's a work
in progress. You know. Freeman Dyson and here's a lot
would listen to me talking this is a very very
highbrow approach to doing things. He would just chuckle and
he'd say, come on, Jill, if you ever make such
an announcement, anybody anywhere on the planet that has access
(36:31):
to a transmit will grab that transmitter and start saying
whatever the hell they please. And then he, you know,
with a twinkle in his eye, and said, wouldn't that
cacophony be about the best representation of the Earth today
that we could make? That sounds like broadcasting Internet comment
sections up to aliens essentially. So the thing that's exciting
(36:54):
but also frustrating to me is that there's so much information,
you know, impacting the Earth, so much electromagnetic radiation and
particle radiation that we're just not gathering. When you talk
about like seeing the whole sky, the information from an
alien species, from an extra trust intelligence could be hitting
the Earth like right now at this moment and just
be you know, absorbed by rocks and concrete and Walmart
(37:15):
parking lots, etcetera. So I wonder, what would you do
if you were given you a billion dollar or ten
billion dollar or an unlimited budget, would be your sort
of fantasy detector or observatory to accomplish this task. We
thought about that, and because we can't promise results, because
we can't say that we're even looking in the right
(37:39):
way right and maybe we should be looking for zeta raise,
except we don't know what zata as are. I would
put that big chunk of money in an endowment, and
I would live off the interest from that endowment to
allow for a multi generational x lauration, an opportunity in
(38:03):
the future to employ technologies that we don't have today.
That would be my approach to it. There's certainly lots
of things that we would like to build, and we're
in the process of building some. And we're also getting
better at this concept of commensal observing. So in the radio,
(38:23):
for example, the very large array in Squarana, Mexico is
probably the most productive radio telescope that we have distrits.
So one of the people at the SETI Institute, andrewson
Ian and his team are figuring out a way to
get the voltage out of all of those antennas and
(38:45):
build uh commence a program for that, and they'll take
that and they'll apply it in the future to the
square kilometer array in South Africa. So there are new
things we'd like to build. We've got is error of
going from I think I already mentioned the ten class
optical telescopes to thirty and forty telescopes, and the large
(39:08):
Synoptic survey telescope looking at all the sky every few days.
We need to figure out how we can piggyback on those,
how we can find things in those data that makes
people go, huh, what's that. So there's a lot of
things coming up neutrino detectors, there have been some suggestions
(39:32):
of how information transferred with neutrinos could impact other parameters
that are easier to detect than the neutrinos themselves. So
I'd like to continue pushing all of those things, looking
at the universe in new ways, looking at archival data
for things like I think I already explained these almost
(39:56):
natural signals, and just keep in mind that the conclusion
that we are alone is so significant that it really
does require a systematic and very thorough exploration of the
(40:17):
cosmos before you're willing to make that conclusion. So, yeah,
give me a lot of money. I'll put in an
endowment a little of the interest and do lots of
interesting new things along the way. I'm sure. Well, if
I was a zillionaire, I would definitely write a big
check to set. So thinking about you know, our real universe,
of course, is absolutely fascinating. But there's a lot of
exploration of this topic in science fiction. And so if
(40:40):
I could ask you, what is your sort of favorite
depiction of extraterrestrial contact in movies or in a book,
your your favorite fictional depiction. Well, Contacted a really great job,
right because it was written by Carl Sagan, who knew
the business. I really liked The Arrival because of the
concept that if you're going to write in circles, you
(41:02):
need to know the future. I thought that was an
intriguing concept. And of course everybody is now remembering Rendezvous
with Rama given the passage of the Muamua through our
solar system. There's another part that I love. It's called
Door in Just Summer, and the hero in the book
lived in this drafty old cottage and it rained a lot,
(41:27):
and he had a cat named Patronius, and the cat
kept going to door after door after door, figuring that
one of those doors is going to open onto sunshine
rather than rain. So I have a cat named patrons wonderful. Well,
thanks very much for taking the time to talk to
us about how humanity is searching for extraterrestrial intelligence, what
(41:48):
we can do and what we are doing in the future.
I hope that the project does continue for another ten
thousand years, and that we managed to put ourselves out
there and speak to the cosmos and let them know
that we're here now. Danny, thank you for this opportunity
to talk to people, because I think it's really important.
I mean, set He is sometimes seen as unimportant and
fringe and not having any real tangible value, but I
(42:13):
disagree with that. I think that if we get to
talk to people and have them think about life evolving
somewhere else, it's like holding up a mirror to the
planet Earth and saying, hey, you, all of you. You
are all the same when compared to something else that
(42:35):
might have evolved on a planet around another star. And
it's important to get that concept across because we face
so many challenges on this planet in our future, and
those challenges are going to require global cooperation to find solutions.
(42:56):
So the more that we can make people think of
themselves as Earthlings rather than Americans, are Chinese some other thing.
We're all the same on this point and we all
have to work together. So I really think Setting has
a very practical application right now, Well, here's one thing
(43:18):
who totally agrees with you. So thanks very much for
devoting your life in your career to this vitally important project.
All right, have a good day, Thanks for listening, and
remember that Daniel and Jorge explained The Universe is a
productional I Heart Radio More podcast for my heart Radio,
(43:41):
visit the I Heart Radio Apple podcasts, or wherever you
listen to your favorite ships.
Hi, it's Jorge and Daniel here. And this holiday season,
if you're looking for a gift for yourself, for a friend,
or for your your family, why not get him the
gift of Answers about the Universe. So check out our
new book Frequently Ask Questions about the Universe. You can
find details at universe f a q dot com. Thanks
for supporting the podcast. Happy holidays everyone. How much have
(00:31):
you thought about what it might be like to talk
to aliens? While biologists wonder about what form alien life
might take, linguists speculate about how we might communicate with them,
and conspiracy theorists wonder whether aliens have already visited Earth
and taken over our government. Physicists have long expressed confidence
that they could most easily find common ground with aliens,
(00:53):
assuming that math and physics are universal, not specific to
Earth biology. Even more than that, physicists practically salivate at
the prospect of learning from aliens answers to big questions
in physics, how to bend space and time, or crack
open black holes and play elaborate pranks on Navy pilots.
But what would it actually be like to try to
(01:14):
learn physics from aliens. Could we even understand the cosmic
secrets they might share with us? Would they be so
advanced it would be like Schrodinger explaining quantum mechanics to
its cat. Do we actually share math and physics with
every intelligent civilization out there? Or would their minds be
so alien it would just be impossible. Hi, I'm Daniel.
(01:49):
I'm a particle physicist, and I can't wait to talk
to the aliens and learn the secrets of the universe.
There are so many things we don't understand about the universe,
and if aliens visit it or managed to send us
a message, it seems likely that they might have been
working on these questions for thousands or millions, or even
billions of years. Imagine catapulting our understanding that far forward.
(02:12):
We might learn about how quantum mechanics really works, or
what's inside a black hole, or how the universe actually began.
But is that making a basic mistake? Assuming the humans
and aliens might think about science in the same way,
how could we possibly anticipate what aliens might know, or
think about or wonder at so Welcome to the podcast.
Daniel and Jorge explain the universe of production of I
(02:35):
Heart Media, in which we dive deep into all these
questions about the universe. We asked the biggest, the deepest,
the craziest questions, and we strain for answers, explaining to
you everything we understand and everything that we don't. My
friend and co host Jorge is on a break, but
I have a special treat for you today. We are
very lucky to have as a guest one of the
leading scholars in the field of the search for extraterrestrial intelligence.
(02:59):
Today we'll be talking to Jill Tarter, astronomer and longtime
chair of the SETI program, the Search for Extra Terrestrial Intelligence,
and so today on the program, we'll be asking the
question how should we be searching for extra terrestrial life?
(03:20):
So it's my great pleasure to introduce Dr Jill Tarter.
She's very well known for leading the SETI program for
many years and is also famous for introducing the phrase
brown dwarf in her pH d thesis, which she completed
at Berkeley nine. But she's also been a leading voice
in the search for extra terrestrial life and intelligence for
more than three decades and has won many awards, including
(03:40):
the Carl Sagan Prize for Science popularization and being elected
to the American Academy of Arts and Sciences. Dr Tarter,
Welcome to the podcast. Thank you for joining us, Thank
you for having me. Daniel. So, I actually dug into
your thesis a little bit and I thought it was
quite fascinating. But it's well. I actually also got my
PhD from Berkeley the several years later, and I was
(04:01):
curious reading through it. It's not obvious the direction of
your career would take. So how did you get into
the search for extraterrestrial intelligence? Like what set you on
that course? Well, it all had to do with Berkeley
and graduate school and it was a big accident. So
my first year at Berkeley, I was supported on our
research assistant ship to program the first computer that we
(04:25):
ever had on our desktop. So it was a PDP
eight slash s now took two people to get it
on the desktop, so it wasn't that small. But the
other thing about it was that it had no language,
so you had to program the whole thing in often
for every instruction you wanted it to do, you had
to set all the ones in zeros. Kind of a
(04:47):
pretty arcane skill, but I found it interesting and fun,
so I did that for a year, and then I
went on to other things. Finally, many years later, when
I was about to finish my PhD and go off
to a post dog, Stu Bowyer, an X ray astronomer,
had a really clever idea. He'd been reading the material
(05:08):
that had been put out by NASA aims on the
search for life beyond Earth, and he said, you know,
UC Berkeley has a radio telescope in northern California, and
he was clever enough to know that with a radio
telescope you can make essentially a noiseless copy of the
voltage coming out of the telescope, and then on your
(05:32):
copy you could process it looking for engineered signals while
the astronomers went ahead and did whatever they were going
to do anyway, So very clever, this idea of observing commensally.
But he had no money, so he went begging for
pieces of equipment, and somebody gave him a hundred channel
p AR auto car. Later, and somebody else gave him
(05:54):
this old p d P A S computer. So somebody
pointed out to Stu that I used to work on
that computer, and he showed up in my office one
afternoon with a copy of the cyclops report that had
been done at NASA, Ames saying the way to find
extraterrestrial intelligence was to build an array of six hundred
(06:15):
meter telescopes. That never happened, but anyway, he gave me
that as a recruiting tool, and I read it and
I just got really hooked. Here I was with potentially
the right skills, in the right place, at the right
time to perhaps make a contribution to answering this age
old question of are we alone? So I worked with
(06:39):
the PDP eight s again and got a program with
Stu up and running at that creek, and then, you know,
as I said, I was hooked, and I've stayed hooked
ever since. It amazes me how we sometimes see sciences
as like linear, natural, obvious progression, but so much of
it depends on random accidents. Who happens to talk to
(07:01):
who and be inspired by what? And if you ran
the Earth science a hundred times in, you know, with
different initial conditions, you might get completely different trajectories of intellectually,
like where we end up as a species. So you
mentioned this, the device that wasn't built. What is SETI
actually doing? What instruments are they using and operating and
what are they actually listening for right now? Well, set
(07:23):
the search for extraterrestrial intelligence, which is a misnomer because
we don't know how to find intelligence, per say, we
can't even define it um. What we're doing is trying
to find evidence that somebody else is using some technology
that we can discover over the vast distances between the stars.
(07:45):
And so it started out as using radio telescopes to
try and find engineered signals, and then over time we
expanded it into optical searches and infrared searches, and now
we are trying to do something that we've known that
(08:06):
we should be doing for the past twenty years, but
just haven't had the technology to do it, and that
is to look for transient signals. And the trick there
is you want to look at all the sky, all
the time, and at as many frequencies as you possibly can.
And so now we are finally able to build starting
(08:28):
in the optical and then moving into the radio telescopes
that look at tens of thousands of square degrees at
a time, and in one case, if we can complete
the instrumentation, all the sky all the time looking for
these transient signals. So that's the exciting frontier for CET
today to try and get this sky coverage. And the
(08:50):
other exciting thing is to begin to look at the
data in a different way. Historically, we have always looked
at data and said, is there a signal of this
description in the data, And we have defined the signals
that we're interested in as being frequency compressed in the radio,
(09:13):
or time compressed in the optical, or monochromatic lasers in
the optical. But now we're beginning to see if we
can use machine learning to help us find patterns of
any kind in the data without having to pre describe
what pattern we're looking for. So we're hoping that algorithms
(09:36):
in the future will be able to look at data
voltage is a function of time, intensity is a function
of time and say there's information content here, or no,
this is all noise. That's fascinating. If we need artificial
intelligence to recognize alien intelligence, well that alien intelligence is
quite likely to be artificial itself by machines, So maybe
(10:01):
we need machines as interpreters. But still we need to
somehow train that machine learning. We need to teach it
the kind of things that we are looking for. We
can't just we're not raising generic intelligence and say go
out and find some aliens, right, doesn't there need to
be some fought in advance for the kinds of things
we're teaching our machine learning algorithms to find. Well, actually,
(10:21):
the real problem is how do you get a null set?
How do you give it data that you know has
no information content. You know, when you have a data
set and we've explored it for X, Y and Z,
it doesn't mean that Q isn't there. So generally to
get a null set you generated randomly on a computer,
(10:44):
and then you can give it lots of examples of
different signals that we have detected or that we generate
ourselves as the counter. And again it's early days. We're
very hopeful and we'll see what happens. Right. I suppose
you can't just take the ABC from the sky and
say assume there's nothing here, because the whole point is
to look for data in the sky, so then it
(11:06):
would learn to ignore signalities there. So you mentioned something fascinating,
which is thinking about the messages that we would send
or the ones that we have sent, and know that
in the early days of space exploration, you know, for example,
there's a Golden Record. We put on some of our probes,
and there's a message we sent out via a Recibo.
How do you look at those messages that we've sent
sort of with modern eyes, How would you design a
(11:28):
message to generic aliens now you hope would be observable
and detectable to the broadest set of intelligence. Well, I
do something that we haven't done with the Acibo message
or any of the other messages that we've transmitted, and
that is I would do it for ten thousand years,
all right. If you send a finite transmission, then that
(11:51):
message is going to go past your target in a
finite amount of time, and the receivers would have to
be looking at you at just the right time, in
just the right way as your message flies past in
order to detect it. And the probability of that is
pretty small. So I think what you want to do
is start transmitting and then don't stop right so that
(12:14):
whenever an emerging technology wakes up and begins to explore
its environment, your signal will be there for them to
find when and if they develop the right technologies and
the right strategy and are motivated to be looking. So
that's I think what I would do. And the reason
(12:36):
that I'm not at all enamored of efforts to transmit
messages today because we're just not grown up enough to
be able to culturally be able to manage such a
long term project. It's like just shouting once in the
night and hoping that somebody hears. You know, it's fascinating
as our message sort of sweeps across the universe. It's
always somewhere, but the chances that it happens to arrive
(12:59):
when some he's listening do seem pretty small. Do you
think that's something our civilization would ever be capable of
sending messages for tens of thousands of years? Do you
think our civilization will last long enough to be able
to do that? I hope so. And in fact, one
of the things that I think about is that suppose
the distribution of lifetimes of technological civilizations or technologies, because
(13:22):
that's what we're going to find is the technology is bimodal,
So you have lots of short lived technologies. They emerge,
develop an either turn themselves off or do themselves in.
They don't have a very long lifetime when compared to
the ten billion year history of the Milky Way, galaxy.
But now there might be an addition, some very long
(13:47):
lived civilizations, And it might be that the probability of
transitioning from short lived technology to a long lived technology
is dependent on discovering other technological civilizations that have made
(14:07):
it to an old age. And I think that's one
of the things that today motivates me to continue working
on this project. How can we have a long future
for life on this planet? And if so, how and
that the answer to me is if anybody else has
made it through, that means we can figure it out too.
(14:29):
Are you suggesting that discovering a longstanding alien civilization might
help us build a civilization that's long standing just knowing
that it's possible. I think that's not unlikely or not impossible.
If I know that there's a solution to a problem,
even if I can't figure it out right now, I
have more motivation to figure out the solution. I know
(14:52):
it's possible, So how the heck am I going to
solve it? That's very insporational. I hope that's true. In
all of these searches were looking for signals, signals generated
by technologies which in the end are somewhat similar to ours.
And there seems to be an implicit assumption there that
you know their information, their messages will be encoded in
(15:13):
ways that are familiar to us, even if the actual
code is alien. The fact that they are sending messages
coded in electromagnetic radiation of some kind assumes that you
know the civilization is mathematical or scientific. Do you think
that it's possible for us to imagine aliens in a
more broad sense, you know, to think about aliens that
(15:33):
might not do math or might not have a scientific exploration,
or do you think that we can only search for
aliens that are sort of similar to us intellectually that
we could ever communicate with them. Well, they're kind of
two pieces to that question. One, we have a certain
amount of technology in the twenty one century, and we
understand a certain subset of physics, and those are the
(15:57):
tools we have. We can't use tools that we don't have.
We can't search for things that we don't yet understand.
And in terms of another technology, we're actually trying to
think more broadly than we originally did, So not just
radio signals or not just optical signals, but something that
(16:20):
we call a techno signature, something that is the result
of someone doing something with technology out there. And it's
particularly important to think about that now because we're moving
from the generation of ten class optical instruments and a
(16:42):
hundred elements in inferometers two thirty forty telescopes and interferometers
like near Cat the square kilometer array that are going
to have thousands of elements. So our ability to see
things on the sky is going to improve dramatically, and
(17:04):
we want to be thinking about, oh, what's that and
how the what's that might be interpreted in terms of technology,
So we're thinking about signals that are almost natural or
things that are obviously engineered. And obviously engineered has been
(17:24):
the piece that we've been doing us far. But when
you begin to think about almost natural, you think about
maybe a pulsar, right, which has a period it's very constant,
and then it changes its period. Now we've seen that
in the data because there are star quakes on these
neutron stars have changed the moment of inertia and change
(17:45):
the period of the pulse sar. But what we haven't
seen is a pulsar that starts at one period, changes
to a second period, and then goes back to the
first period. But those could well be in our data
sets as we searched the sky for pulsars, So it's
almost natural, and we would catch it in a net
(18:06):
when we're doing an astronomy survey. So another example I
like to think about is transit. So we've been finding
all these exoplanets because they cast a shadow on the
image of the star and change the stellar luminosity as
the planet transits in front of the star. Now, the
(18:26):
i AU has declared that planets are spherical, right, and
so their shadows are going to be circular. But what
about some giant constructed artifact that's like a Venetian blind
or a triangle. Well, in the higher order moments of
the light curve at ingress and egress, you could tell
(18:48):
the difference if you looked hard enough, between a triangular
shadow and a circular shadow. So that might be an
almost natural signal that would in fact ultimately lead us
to technology. Wow. Fascinating. So we have a whole spectrum
of things which we classify as natural because we think
(19:12):
they're not the product of intelligent action. Things are clearly artificial,
like the signal that says hello, we got your air
cebra message. Here's our address, and now you're imagining things
in between, which are subtle evidence of deviations from sort
of natural evolution of the universe because of intelligent actions.
You know, we're going to have so many new and
(19:32):
different eyes on the cosmos that we ought to be
broadening our thinking. That's fascinating and it seems like a
very worthwhile It still seems to me to be indicative
of sort of the way that our minds work. You know,
we build things that are square, and we build things
that are symmetric, and we're imagining that maybe aliens could
do that as well. And I certainly take your point
(19:53):
that we can't look for things that we don't understand,
and we can't look for things that we can't imagine.
Does that frustrate you that you know that might be
that the spectrum of intelligence aliens out there could be
so much broader than we can imagine that it might
make it impossible to ever discover them. Yeah. Well, for
the longest time, we said, okay, if they have some
technology that we might be able to detect in some fashion,
(20:16):
they're going to have to have math, right, can't build
things without some artificial way to represent them and construct them,
And so we thought, okay, so that means math is
the universal language of the cosmos. And then we had
some really interesting talks at the Cutty Institute by people
(20:37):
who study the human brain, and they pointed out that, yeah,
they might well have math and be representing exactly the
same things that are mathematical programs do, but that our
math and the way we represent things is inevitably shape
(21:00):
by the nature and structure of our human brain. And
so they might well be talking about exactly the same thing,
the same mathematics, but the representation of it might be
so different that we don't recognize it as such. So
now that's so are right now. And if you look
back at the sort of history of the development of
(21:23):
mathematics and the philosophy of mathematics, you know there are
still like big open questions about how to even build
a mathematical system that's self consistent, and a lot of
mathematicians practicing mathematicians sort of ignore that and say, look,
we have a system that mostly works. We can get
stuff done. But it tells you that if human history
had gone another way, if a different philosopher had been
(21:43):
born or been influential, we might all think very differently mathematically,
And so the spectrum of like possible human explorations of
you know, ways to think is so potentially broad, and
it's sort of terrifying to imagine how broad it might
be when you're including, yeah, well there are anthropologists who
tell us that there are some very isolated tribal groups
(22:05):
that don't have a zero in their worldview. So you
can do what you can do, and you can't do
what you can't yet do. So you've been working on
(22:28):
this for a while. How long do you expect that
this project might take? I mean when LEGO turned on,
for example, I remember thinking, well, they have no idea
how common gravitational waves are, and they had no clue
whether they would wait decades for the first signal, And
of course they were lucky they heard something almost immediately,
and it's been a treasure trove. Do you harbor such
hopes that, you know, if we expand our capabilities to
(22:49):
listen to the sky, that we might learn something too.
I don't know about soon. I think this could well
be a multi generation all exploration. And the reason I
say that is that the volume that might need to
be searched, even if an electromagnetic signal is the right
(23:10):
thing to be looking for. That volume is really vast,
and so when c turned fifty, I tried to do
calculation that would show how vast it was and how
much we had searched to date for an electromagnetic signal. Again,
assuming that's the right thing to be looking for, there
(23:32):
are nine different parameters that you have to explore space
and time and polarization and modulation and intensity, all of us.
And so I tried to make a guess at what
the range of each of those parameters might be, and
then I multiplied them all together some sort of a
nine dimensional volume. And I'm not any good at visualizing
(23:56):
nine dimensional volumes. So I said, okay, here's the analogy
that volume. I'm going to set it equal to the
volume of all the Earth's oceans and then ask how
much of the Earth's oceans have we searched in fifty years.
And at that time the answer was one glass of
(24:16):
water out of the ocean. Right. That shows you how
vast the search might need to be. And then when
city turned sixty, ten years later, the students at Penn State,
we did the calculation and they said, it's not a glass,
it's more like a small swimming pool, so that was
a big improvement over ten years, but still not a
(24:39):
lot of the oceans. So I think that it might
be multi generational, either because we haven't yet invented the
right technology, we don't understand the physics that's involved, or
simply because the search is so vast it's going to
take a while. It's getting faster all the time, primarily
(25:02):
because of Moore's law and the improvements in our computational capabilities,
but it may have to go on for a while.
The exciting thing for me about research like that is
that you just don't know until you begin if you're
searching for a signal which is obvious or really subtle.
Like in your ocean analogy, you only need a glass
of water to find salt, right, but if you're looking
(25:22):
for a particular fish, you may have to look through
millions and millions of glasses. And in our case, we
just don't know right how many civilizations are out there
they're super rare, or if they're everywhere. So have your
hope sort of changed over the years that when you
first got involved in this, in your that first project
you described using the PDP, did you think I might
discover aliens tomorrow. If your hopes sort of kept up
(25:44):
or have they dimmed over the decades, well that's still true.
We could discover something tomorrow, or it might be my
granddaughter's generation that succeeds. We don't know, And this is
one of those questions that you don't know the answer
until you find the answer. And if anybody you know,
if I told you anything different, right, that would be
(26:07):
religion and not science. So no one knows. I still
think it's worthwhile. Humans have been asking themselves this question
since we walked out of the caves. We're really intrigued
with how we fit into the cosmos, how we compare
something else that might be out there. So every day
(26:29):
you're looking at information could be the day that you
get the signal that says wow. And now, like human
history pivots on that point, before that moment and after
that moment. So in your career or in the decades
of that we've been doing this, have there been any
moments when you thought to yourself, this could be any
sort of like, oh, this looks real kind of moments. Yeah,
there have been a few, and they've all turned out
(26:51):
to be false positives. But some of them took a
lot longer to dismiss than others. Let's see, we usually
observe with two widely spaced telescopes, and we require that
the signal be found at both and that it had
(27:14):
the appropriate light travel time between them, and that it
have if it's a narrowband signal, we can require that
it have a differential Doppler signature that represents the Earth's rotation. Right,
So we have all these tests that we need to do.
But back in nineteen I think it was, we were
(27:36):
using a telescope in green Banquest, Virginia and another one
in Woodbury, Georgia, and lightning struck the telescope in Georgia
and went through the electronics and frieda district, so that
telescope was off the air for days before FedEx could
get a new dis drive into the facility. But we
(27:57):
still had time. And that's of course a very racious
thing on the telescope in green Bank, West Virginia. So
we kept observing with that one telescope in a manner
that radio astronomers have often used. They stare at a
target source and then they look away, and then they
go back and they differentiate between the on and the
(28:20):
off source. So we we tried that with the Green
Bank telescope and sort of like five o'clock in the morning,
I saw a signal that was clearly artificial. Looked in
this waterfall plot, as we call it, like a picket fence.
So I saw multiple frequencies lit up, and the spacing
(28:42):
between those frequency features was constant. That's not another nature.
And so I saw this every time I looked at
the target that we were tracking, and every time we
pointed the telescope away from that target, it went away.
And this went on for a while, and then I
(29:02):
finally got clever idea. I said, okay, we've been observing
here for a couple of weeks. Let me look through
all the data that we have taken when looking at
other parts of the sky and see if we've ever
seen a signal that has that frequency spacing. Right, that's
a very significant characteristic. And so I wrote a program
(29:25):
and it actually compiled me and I ran it, but
I was in I was excited. I mean I was
really excited, and so I was sloppy with my output,
and when I looked at the output, I actually missed
the fact that, yes, we've seen that particular signature when
looking in other places on the sky, but you know,
(29:47):
being excited and I dismissed it. So we continued tracking
that and I woke up my colleagues, got them to help,
and finally, as the source set in the west, the
change in the drift rate that changed with frequency and
(30:08):
time of the signal was consistent with something that was
rising to the zenith, not setting on the horizon, and
so sadly, by the end of the afternoon we knew
that this wasn't a real extraterrestrial signal. We didn't know
(30:29):
what it was. It took a while of doing web
searches and it turned out it was the Soho spacecraft
in orbit, not around the Earth we would have caught
that much earlier, but around the sun. And telescopes, like
human eyes, which have peripheral vision, telescopes have sidelobes where
(30:53):
the sensitivity is much lower, but it's not zero, And
so every time I pointed at the target, the Sun
would be in the sidelo, and when I moved the
telescope to the different direction, the sun fell out of
that silo and the sun tracked the Earth's rotation just
as the target ten, and so it took us a
(31:13):
while to figure that one out, but it was exciting.
It was really an enormous amount of adrenaline, and then
disappointing when we figured it out and we figured out
a couple of different ways to avoid having that happened
to us again well as a fascinating moment, because on
one hand, you desperately want to believe it's sort of
(31:33):
your scientific fantasy. On the other hand, you want to
push on it as hard as possible because you definitely
don't want to announce something if it's not real, and
so you have to be like the biggest cheerleader and
also be the biggest skeptic at the same time. Yeah,
make me a liar exactly. So what would happen and
(32:04):
walk us through what would happen if you got a
signal and you were not able to identify as coming
from any satellite or any nearby object, and all the
evidence pointed to it coming from another star and it
seemed sincerely artificial. Is there you know, a real protocol
sort of politically for what happens in that scenario? Do
you have to contact US government or are you're allowed
to talk to scientists from other countries about it. Well,
(32:26):
when we were ann asked the project, Yeah, there was
a protocol and it included which associate administrator was going
to notify in the White House, right, and it was
that detail. Now that we are philanthropically privately funded and
the other SETI projects like break through Lists and are
also privately funded, there is a protocol that we've informally
(32:49):
agreed upon. It has no enforceability, but basically it says,
at the discovery site, you try and use another instrument
now that you know what you're looking for. Probably a
normal off the shelf Hewlett Packard spectrometer will allow you
to find that signal. So you try and just detected
(33:10):
with instrumentation that you didn't build and software that you
didn't write as a confirmation. And then if you do
that and you have some more confidence, then indeed you
do quietly call up the director of some observatory to
the west and ask for a little bit of discretionary
(33:32):
time to see, knowing what they're looking for, if they
can detect the signal, and that's probably your best hedge
against a hoax and deliberate hopes. And then if you
get that independent confirmation, then you sit down and figure
out how you're going to tell the world. And one
of the things that you might consider doing is sending
(33:54):
out what used to be called an I A U telegraph,
something that goes to all the observatories around the world,
discreetly telling them what you've found and prepping them for
the fact that there will be a press conference coming
up very quickly, because what you want to do is
train up a bunch of professionals who can interpret for
(34:18):
their local media what's actually been found, and not leave
the media to make it up for themselves, right, because
it's probably going to be maybe ambiguous, right, and you
don't want the media writing their own story, so you'd
like to give them as much assistance in understanding what's
(34:40):
really been discovered. And then you tell the world, and
you want to be very careful that you make sure
that everyone who's been involved in any way gets appropriate credit.
Then you hope that the network at the study institute
or wherever the discovery site is doesn't melt from the
world trying to get hold of you, and you see
(35:00):
what happens. So walk through a hypothetical best case scenario.
Say we see an artificial signal and other people confirm it,
and we believe that it's there, then what do we do?
Do we respond? Do you write a message back and
you spend a decade trying to decode it, understand the
contents of it, and debate how to respond. Did we
spend you know, a hundred years going back and forth
(35:20):
before we learn each other's language and understand each other's mathematics. Oh,
we've thought about it, and we've held workshops and basically,
should we respond? And if so, who will speak for Earth?
And what will they say? And I think the disappointing
thing for me at the moment is so we've held
a number of workshops, they haven't really involved very much
(35:43):
of the world's diverse cultures. It's been sort of pretty
waspy and pretty male. So we continue to think about this,
and I continue to try and find a way two
take this question globally and find appropriate venues to ask
other cultures in other ways of being and thinking what
(36:07):
they would do, how they feel. So it's a work
in progress. You know. Freeman Dyson and here's a lot
would listen to me talking this is a very very
highbrow approach to doing things. He would just chuckle and
he'd say, come on, Jill, if you ever make such
an announcement, anybody anywhere on the planet that has access
(36:31):
to a transmit will grab that transmitter and start saying
whatever the hell they please. And then he, you know,
with a twinkle in his eye, and said, wouldn't that
cacophony be about the best representation of the Earth today
that we could make? That sounds like broadcasting Internet comment
sections up to aliens essentially. So the thing that's exciting
(36:54):
but also frustrating to me is that there's so much information,
you know, impacting the Earth, so much electromagnetic radiation and
particle radiation that we're just not gathering. When you talk
about like seeing the whole sky, the information from an
alien species, from an extra trust intelligence could be hitting
the Earth like right now at this moment and just
be you know, absorbed by rocks and concrete and Walmart
(37:15):
parking lots, etcetera. So I wonder, what would you do
if you were given you a billion dollar or ten
billion dollar or an unlimited budget, would be your sort
of fantasy detector or observatory to accomplish this task. We
thought about that, and because we can't promise results, because
we can't say that we're even looking in the right
(37:39):
way right and maybe we should be looking for zeta raise,
except we don't know what zata as are. I would
put that big chunk of money in an endowment, and
I would live off the interest from that endowment to
allow for a multi generational x lauration, an opportunity in
(38:03):
the future to employ technologies that we don't have today.
That would be my approach to it. There's certainly lots
of things that we would like to build, and we're
in the process of building some. And we're also getting
better at this concept of commensal observing. So in the radio,
(38:23):
for example, the very large array in Squarana, Mexico is
probably the most productive radio telescope that we have distrits.
So one of the people at the SETI Institute, andrewson
Ian and his team are figuring out a way to
get the voltage out of all of those antennas and
(38:45):
build uh commence a program for that, and they'll take
that and they'll apply it in the future to the
square kilometer array in South Africa. So there are new
things we'd like to build. We've got is error of
going from I think I already mentioned the ten class
optical telescopes to thirty and forty telescopes, and the large
(39:08):
Synoptic survey telescope looking at all the sky every few days.
We need to figure out how we can piggyback on those,
how we can find things in those data that makes
people go, huh, what's that. So there's a lot of
things coming up neutrino detectors, there have been some suggestions
(39:32):
of how information transferred with neutrinos could impact other parameters
that are easier to detect than the neutrinos themselves. So
I'd like to continue pushing all of those things, looking
at the universe in new ways, looking at archival data
for things like I think I already explained these almost
(39:56):
natural signals, and just keep in mind that the conclusion
that we are alone is so significant that it really
does require a systematic and very thorough exploration of the
(40:17):
cosmos before you're willing to make that conclusion. So, yeah,
give me a lot of money. I'll put in an
endowment a little of the interest and do lots of
interesting new things along the way. I'm sure. Well, if
I was a zillionaire, I would definitely write a big
check to set. So thinking about you know, our real universe,
of course, is absolutely fascinating. But there's a lot of
exploration of this topic in science fiction. And so if
(40:40):
I could ask you, what is your sort of favorite
depiction of extraterrestrial contact in movies or in a book,
your your favorite fictional depiction. Well, Contacted a really great job,
right because it was written by Carl Sagan, who knew
the business. I really liked The Arrival because of the
concept that if you're going to write in circles, you
(41:02):
need to know the future. I thought that was an
intriguing concept. And of course everybody is now remembering Rendezvous
with Rama given the passage of the Muamua through our
solar system. There's another part that I love. It's called
Door in Just Summer, and the hero in the book
lived in this drafty old cottage and it rained a lot,
(41:27):
and he had a cat named Patronius, and the cat
kept going to door after door after door, figuring that
one of those doors is going to open onto sunshine
rather than rain. So I have a cat named patrons wonderful. Well,
thanks very much for taking the time to talk to
us about how humanity is searching for extraterrestrial intelligence, what
(41:48):
we can do and what we are doing in the future.
I hope that the project does continue for another ten
thousand years, and that we managed to put ourselves out
there and speak to the cosmos and let them know
that we're here now. Danny, thank you for this opportunity
to talk to people, because I think it's really important.
I mean, set He is sometimes seen as unimportant and
fringe and not having any real tangible value, but I
(42:13):
disagree with that. I think that if we get to
talk to people and have them think about life evolving
somewhere else, it's like holding up a mirror to the
planet Earth and saying, hey, you, all of you. You
are all the same when compared to something else that
(42:35):
might have evolved on a planet around another star. And
it's important to get that concept across because we face
so many challenges on this planet in our future, and
those challenges are going to require global cooperation to find solutions.
(42:56):
So the more that we can make people think of
themselves as Earthlings rather than Americans, are Chinese some other thing.
We're all the same on this point and we all
have to work together. So I really think Setting has
a very practical application right now, Well, here's one thing
(43:18):
who totally agrees with you. So thanks very much for
devoting your life in your career to this vitally important project.
All right, have a good day, Thanks for listening, and
remember that Daniel and Jorge explained The Universe is a
productional I Heart Radio More podcast for my heart Radio,
(43:41):
visit the I Heart Radio Apple podcasts, or wherever you
listen to your favorite ships.
Hosts And Creators
Daniel Whiteson
Kelly Weinersmith
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