>>Jill Tarter: So are we alone?
That's a pretty old and fundamental human question.
To quote a very eminent astronomer, Dr. Ellie Arroway, if we are, it seems like an awful
waste of space.
But putting science fiction aside, if you want to try and find an answer to this question
as a scientist, you have to begin to consider how we perceive the world around us and where
we actually are.
Well, obviously, we're here, enjoying ourselves very much.
And Google Earth has allowed us to comprehend that we're here, from the altitude of low
Earth orbit satellites, we're here.
And since 1968, we've been able to comprehend and envision ourselves here.
The Cassini Spacecraft orbiting Saturn looked through its rings and saw us here.
And in 1980, as the Voyager 1 spacecraft was passing Neptune on its way out of the solar
system, it turned around, looked homeward, and saw us here, as a pale blue dot.
We're here in the boondocks of a large spiral Galaxy out at the edge nowhere near the center.
And our sun is just one of about 400 billion stars in this Galaxy.
And the Milky Way Galaxy is actually here.
It's one of 100 billion or more galaxies in our observable universe.
But we've only recently come to understand that it takes a Cosmos to make a human.
We humans have a very deep and intimate relationship with the universe.
We humans trace our lineage not just back centuries through our families, or back through
millennia for our civilizations, not just back over the millions of years since we branched
off from the apes, nor back the 2.4 billion years that the Earth's atmosphere has been
profused with oxygen due to the labors of photosynthetic cyanobacteria.
And not just back to the formation of the sun and our solar system 5 billion years ago,
but all the way back to a supernova explosion and the death of a massive star about 8 billion
years ago.
So the iron in the hemoglobin molecules in your blood was fused deep within a massive
star that ended its life in a supernova explosion, leaving metal-rich remnants such as this recent
Nova explosion.
And these remnants are waiting to be incorporated into the next generation of stars and planets
and perhaps life.
So those of us who are in this room are very privileged for a number of reasons, one of
them being that we are among the first generation to be able to comprehend that the world around
us is actually a fragile island of life in a universe of possibilities.
So extremophiles such as these are beginning to illuminate the amazing possibilities for
life in every nook and cranny of this planet.
And they're suggesting the potential for a lot more habitable real estate out there,
perhaps on other planets in our solar system.
This upclose and personal view of Mars is being brought to us by Curiosity, the Mars
science laboratory that landed in early August.
I think it's awesome.
That should be Camelback Mountain, given the detail.
But it's Mars.
And alternatively, all right, life might be found in the water oceans beneath the icy
shells of Europa or Callisto or Ganymead, these large moons of Jupiter.
Or maybe in the ethane lakes of Titan, which is Saturn's large moon.
Or even possibly on one of the gazillions of icy comets in the oort cloud that surround
our solar system.
And we're learning that planets exist in other systems.
It's now looking like there are more planets out there than there are stars.
And ground-based astronomers are scrambling mightily to confirm the thousands of exoplanet
candidates that the Kepler spacecraft has provided us and will be providing us with
some more this month.
In fact, in our search for life, we have this particular chauvinism.
We like -- we have a bias for planets that might have liquid water on their surfaces.
These so-called "habitable worlds."
And so far, there are 46 within this cadre of Kepler candidates.
So these habitable worlds, given our biases and our definitions, they do and should receive
special attention.
But, actually, all of these exoplanetary systems are worthy of exploration.
And it's only if we look at them all that we can hedge against our biases, thinking
we know more than we actually do know.
But many of these exoplanet systems out there are turning out to be multiple planet systems,
are really different than our own solar system, our own nice, neat, clockwork solar system,
where we used to build mechanical orreries and turn the crank and watch the planet go
around.
These multiplanet systems are allowing us to learn amazing lessons about the formation
of planets and planetary systems.
And their diversity reminds us just how hard it is to predict the diversity and abundance
of possibilities in the world around us.
When you have only one example, we thought all of those were going to look just like
ours.
And we were so wrong.
So in the middle of the 20th century, the descendents of World War II radars were turned
skyward and the field of radio astronomy was born.
And that gave us new tools to use in trying to answer the questions about our place in
the Cosmos.
So in 1959, Giuseppi Cocconi and Phil Morrison published the first scientific paper on this
subject, suggesting that the radio astronomer's tools could be used, perhaps, to search for
cosmic company.
And independently, Frank Drake, in 1960, used the Tattle Telescope in Green Bank, West Virginia,
to make the first radio search of two nearby stars, listening for someone else's technology.
And in those years, the exploratory science that we called SETI, the search for extraterrestrial
intelligence, was born.
So at the dawn of the current 21st century, SETI harnessed the power of newly affordable
optical sensors that can count photons as they arrive at the telescope, can count them
rapidly enough to figure out how many photons arrive every single nanosecond.
And this has enabled new searches for technological civilizations that might be transmitting bright
laser pulses.
So the toolbox of SETI researchers continues to expand, and will expand further in the
future, incorporating technologies that we don't yet even comprehend.
We reserve the right to get smarter.
So today -- and, actually, tomorrow, but I can't tell you today -- scientists are eagerly
anticipating the discovery of Earth 2.0, a planet the size and mass of the Earth, at
the Earth's distance, circling a sun-like star, a potentially habitable world.
But for me, Earth 2.0 would be a world that was inhabited by technologists.
So our own technology is visible over interstellar distances, and their technology might be as
well.
Some grand communications network, some shield against asteroid impacts or something totally
unthinkable might produce signals at optical and radio wavelengths which we could detect
with a determined search.
And what, in fact, will determine the success or failure in SETI is the average distance
between technological civilizations.
Now, that's distance in space and distance across time.
So unless two technological civilizations are close enough in space and are coeval,
they exist at the same time, SETI will never succeed.
So longevity is the key to success.
Unless most technological civilizations in fact grow old, SETI will not succeed.
So we are a very young technology in a 10 billion year old galaxy, and we don't yet
know whether technologies can persist.
So Philip Morrison expressed this idea very powerfully.
He said, "SETI is the archaeology of the future."
And now I know perhaps he stole that phrase from you, John.
What we mean here is that the tyranny of light speed means that any information contained
in a signal that's detected will tell us about their past.
But the fact that we detect a signal and the longevity required for that successful detection
tells us that there's a possibility that we can have a long future as a technology.
So SETI has been searching for a bit more than 50 years.
And we've been trying to explore this cosmic ocean.
But so far, if you take the ocean's volume as an analog and you restrict yourself to
electromagnetic signals, I calculate that so far, we've looked at about one eight-ounce
glass out of that water.
[ Laughter ] >>Jill Tarter: But that cosmic ocean beckons
us.
The cosmic ocean is huge, the task is huge.
But it excites us, because our tools are getting fast exponentially.
In Northern California, we've commissioned the first phase of the Allen Telescope Array
with 42 telescopes.
It's the first time we've built an array of a large number of dishes connected with computers.
So that makes silicon as important as aluminum and steel.
And growth potential in the future lies both in building out this telescope with more dishes
for more sensitivity, perhaps to as many as 350 such dishes, and also in leveraging Moore's
Law to get more processing power to be able to look for more kinds of signals.
And many of you in this room have the resources and the skills to help us with this.
And I think that or I predict that you'd probably enjoy the challenges.
So I'd like to talk with you.
All right.
Today, radio and optical SETI searches are looking for simple signal artifacts that have
been compressed either in frequency or in time, signals that we don't think nature can
produce but we know technologies can.
So here, for instance, it's a waterfall plot.
It's a two-dimensional plot, a frequency-time domain.
What's in there is the carrier signal from the Voyager 1 spacecraft, the most distant
human object.
Have you seen it yet?
Well, even without the specific phase lock loops of NASA's big DSN receiving telescopes,
the extremely efficient algorithms that work on the Allen Telescope Array can find that
signal extremely quickly and easily.
It's very detectable.
These are simple artifacts.
Tomorrow, with increased computational capability, we can permit searches from more complex patterns.
And we're doing our searches in real time.
That's our challenge.
Maybe you'd like to help.
Over the millennia, we've seen where tribalism leads.
We've seen what happens when you divide the world around us into smaller islands.
But, ultimately, all of us belong to only one tribe.
We're all Earthlings.
And as members of that tribe, we really owe it to ourselves and each other to celebrate
our commonalities rather than our perceived differences.
And from this perspective, the violence against women and neighbors that we discussed yesterday
and today just seems so much more absurd and unjustifiable and not something that we want
to keep within our world.
So SETI is a mirror that can show us ourselves from an extraordinary point of view, a mirror
that can trivialize the differences among us.
And if SETI does nothing else but reveal this perspective to the world around us to every
human being, it will be among the most profound endeavors in all history.
So this perspective is a meme.
So call it the cosmic meme, the Earthling meme.
It's an idea.
It's an idea capable of spreading light in darkness.
And the important thing about a meme concept is that it can be spread.
By encouraging the act of participation of all Earthlings in this ultimate search for
cosmic company, the meme can proliferate.
Today, we're uniquely positioned.
All right, technology and social media can make this happen.
Spreading the cosmic meme can become a form of nonprofit collaboration.
And in Clinton's words, creative cooperation.
And companies and individuals can build reputation capital by spreading this meme.
So it took a Cosmos to make a human.
And it will take all humans working together to solve the challenges that we face in the
world around us.
A robust SETI program can in fact spread this meme and foster the cooperation that's needed
to deal with the many problems that do not respect national boundaries.
Ultimately, we are star dust, capable of studying the stars.
We are, all of us, what happens when a primordial mixture of hydrogen and helium evolves for
so long that it begins to ask where it came from.
At the SETI Institute, we've seen just how powerful this cosmic meme can be in the classroom
and how physics and math and biology and chemistry are so enjoyable to students within the context
of this really compelling cosmic meme.
And I hope that it will motivate them to innovate the new technologies that drive the changes
that are going to be needed to sustain the world around us.
SETI's kind of like a startup; right?
The odds are long, but if it's done right, it can change the world.
So in searching for others, we may finally come to know who we are and be able to secure
that long future for the world around us.
I look forward to talking with some of you about how to push this forward.
Thank you.