This is the first of two rather extraordinary photographs I'm going to show you today.
It was taken 18 years ago.
I was 19 years old at the time.
I had just returned from one of the deepest dives I'd ever made at that time -- a little over 200 feet.
And I had caught this little fish.
It turns out that particular one was the first of its kind ever taken alive.
I'm not just an ichthyologist, I'm a bona fide fish nerd.
And to a fish nerd, this is some pretty exciting stuff.
More exciting was the fact that the person who took this photo is a guy named Jack Randall, the greatest living ichthyologist on earth -- the Grand Poobah of fish nerds, if you will.
And so, it was really exciting to me to have this moment in time.
It set the course for the rest of my life.
But really, the most significant, most profound thing about this picture is it was taken two days before I was completely paralyzed from the neck down.
I made a really stupid kind of mistake that most 19-year-old males do when they think they're immortal, and I got a bad case of the bends and was paralyzed, and had to be flown back for treatment.
I learned two really important things that day.
The first thing I learned -- well, I'm mortal.
That's a really big one.
And the second thing I learned was that I knew, with profound certainty, that this is exactly what I was going to do for the rest of my life.
I had to focus all my energies towards going to find new species of things down on deep coral reefs.
When you think of a coral reef, this is what most people think of: these big, hard, elaborate corals, lots of bright, colorful fishes and things.
But this is really just the tip of the iceberg.
If you look at this diagram of a coral reef, we know a lot about that part up near the top.
The reason we know so much about it is scuba divers can very easily go down there and access it.
There is a problem with scuba, though, in that it imposes some limitations on how deep you can go.
It turns out that depth is about 200 feet.
I'll get into why that is in just a minute, but the point is, scuba divers generally stay less than 100 feet deep, and very rarely go much below this, at least, not with any kind of sanity.
So to go deeper, most biologists have turned to submersibles.
Now, submersibles are great, wonderful things, but if you're going to spend 30,000 dollars a day to use one of these things and it's capable of going 2,000 feet, you're not going to go farting around up here in a couple of hundred feet, you're going to go way down deep.
So the bottom line is, almost all research using submersibles has taken place well below 500 feet.
Now, it's pretty obvious at this point there's a zone here in the middle.
That's the zone that centers around my own personal pursuit of happiness.
I want to find out what's in this zone; we know almost nothing about it.
Scuba divers can't get there, submarines go right on past it.
It took me a year to learn to walk again after my diving accident in Palau.
During that year, I spent a lot of time learning about the physics and physiology of diving and how to overcome these limitations.
I'm just going to show you a basic idea.
We're all breathing air right now.
Air is a mixture of oxygen and nitrogen, 20 percent oxygen, 80 percent nitrogen.
It's in our lungs.
And there's a phenomenon called Henry's law, that says gases will dissolve into a fluid in proportion to the partial pressures you're exposing them to.
So, basically the gas dissolves into our body.
The oxygen is bound by metabolism, we use it for energy.
The nitrogen sort of floats around in our blood and tissues.
That's fine, it's how we're designed.
The problem happens when you go underwater.
The deeper you go underwater, the higher the pressure is.
If you were to go down to a depth of about 130 feet, which is the recommended limit for most scuba divers, you'd get this pressure effect.
The effect of that pressure is you have an increased density of gas molecules in every breath you take.
Over time, those gas molecules dissolve into your blood and tissues and start to fill you up.
Now, if you were to go down to, say, 300 feet, you don't have five times as many gas molecules in your lungs, you've got 10 times as many gas molecules in your lungs.
And, sure enough, they dissolve into your blood and tissues as well.
And if you were to go down to where there's 15 times as much -- the deeper you go, the more exacerbating the problem becomes.
The limitation of diving with air is all those dots in your body, all the nitrogen and all the oxygen.
There are three basic limitations of scuba diving.
The first limitation is the oxygen -- oxygen toxicity.
Now, we all know the song: "Love is like oxygen.
You get too much, you get too high.
Not enough, and you're gonna die."
Well, in the context of diving, you get too much, you die also.
You die because oxygen toxicity can cause a seizure.
It makes you convulse underwater -- not a good thing to happen underwater.
It happens because there's too much concentration of oxygen in your body.
The nitrogen has two problems.
One of them is what Jacques Cousteau called "rapture of the deep."
It's nitrogen narcosis.
It makes you loopy; the deeper you go, the loopier you get.
You don't want to drive drunk, you don't want to dive drunk.
So that's a real big problem.
And of course, the third problem is the one I found out the hard way in Palau, which is the bends.
One thing I forgot to mention is that to obviate the problem of nitrogen narcosis -- all of those blue dots in our body -- you remove the nitrogen and replace it with helium.
Helium's a gas; there're a lot of reasons why helium's good, it's a tiny molecule, it's inert, it doesn't give you narcosis.
So that's the basic concept we use.
But the theory's relatively easy.
The tricky part is the implementation.
So this is how I began about 15 years ago.
I'll admit, it wasn't exactly the smartest of starts, but you've got to start somewhere.
(Laughter) At the time, I wasn't the only one who didn't know what I was doing.
Almost nobody did.
This rig was actually used for a dive of 300 feet.
But over time we got better at it, and we came up with this really sophisticated-looking rig with four scuba tanks, five regulators and all the right gas mixtures, all that good stuff.
It was fine and dandy, it allowed us to go down and find new species.
This picture was taken at 300 feet, catching new species of fish.
The problem was it didn't allow us much time.
For all its bulk and size, it only gave us about 15 minutes at most down at those sorts of depths.
We needed more time.
There had to be a better way.
And indeed, there is a better way.
In 1994, I was fortunate enough to get access to these prototype closed-circuit rebreathers.
Closed-circuit rebreather: what makes it different from scuba, and why is it better?
Well, there are three main advantages to a rebreather.
One, they're quiet, they don't make any noise.
Two, they allow you to stay underwater longer.
Three, they allow you to go deeper.
How is it that they do that?
In order to really understand how they do that, you have to look underneath the hood and see what's going on.
There are three basic systems to a closed-circuit rebreather.
The most fundamental is called the breathing loop.
It's a breathing loop because you breathe off of it; it's a closed loop, and you breathe the same gas around and around.
There's a mouthpiece that you put in your mouth, and there's a counter lung, or in this case, two counter lungs.
The counter lungs aren't high tech, they're simply flexible bags.
They allow you to mechanically breathe, mechanically ventilate.
When you exhale, it goes in the exhale counter lung; when you inhale, it comes from the inhale counter lung.
It's just pure mechanics, allowing you to cycle air through this breathing loop.
The other component on a breathing loop is the carbon-dioxide-absorbent canister.
Now, as we breathe, we produce carbon dioxide, and that carbon dioxide needs to be scrubbed out of the system.
There's a chemical filter in there that pulls the carbon dioxide out of the breathing gas, so that when it comes back to us, it's safe to breathe again.
That's the breathing loop in a nutshell.
The second main component of a closed-circuit rebreather is the gas system.
The primary purpose of the gas system is to provide oxygen, to replenish the oxygen that your body consumes.
So the main tank, the main critical thing, is this oxygen gas supply cylinder we have here.
But if we only had an oxygen gas supply cylinder, we wouldn't be able to go very deep, because we'd run into oxygen toxicity very quickly.
So we need another gas, something to dilute the oxygen with.
And that, fittingly enough, is called the diluent gas supply.
In our applications, we generally put air inside this diluent gas supply, because it's a very cheap and easy source of nitrogen.
So that's where we get our nitrogen from.
But if we want to go deeper, of course, we need another gas supply, and helium is what we really need to go deep.
Usually we'll have a slightly larger cylinder, mounted exterior on the rebreather, like this.
That's what we use to inject, as we start to do our deep dives.
We also have a second oxygen cylinder, solely as a backup; if there's a problem with our first oxygen supply, we can continue to breathe.
The way you manage all these different gases and different gas supplies is this really high-tech, sophisticated gas block up on the front here, where it's easy to reach.
It's got the valves and knobs and things you need to inject the right gases at the right time.
Normally, you don't have to do that, because all of it's done automatically with the electronics, the third system of a rebreather.
The most critical part of a rebreather are the oxygen sensors.
You need three, so if one goes bad, you know which one it is.
You need voting logic.
You also have three microprocessors.
Any one of those computers can run the entire system, so if you have to lose two of them, there's back-up power supplies.
And there are multiple displays, to get the information to the diver.
This is the high-tech gadgetry that allows us to do what we do on these deep dives.
I can talk about it all day -- just ask my wife -- but I want to move on to something much more interesting.
I'm going to take you on a deep dive, and show you what it's like to do one.
We start up on the boat, For all this high-tech, expensive equipment, this is still the best way to get in the water, just flop over the side of the boat.
Now, as I showed you in the earlier diagram, these reefs that we dive on start out near the surface and they go almost vertically, completely straight down.
So we drop in the water and go over the edge of this cliff, and then we start dropping, dropping, dropping.
People ask if it takes a long time to get there.
No; it only takes a couple minutes to get down to three or four hundred feet, which is what we're aiming for.
It's like skydiving in slow motion.
It's really very interesting.
You ever see "The Abyss," where Ed Harris is sinking down along the side of the wall?
That's what it feels like.
Amazing.
And down there, you find that the water is very clear, extremely clear, because there's hardly any plankton.
When you turn on your light and look around the caves, you're confronted with a tremendous amount of diversity, much more than anyone used to believe.
Now, not all of it is new species -- that fish you see with the white stripe, that's a known species.
But if you look carefully into the cracks and crevices, you'll see little things scurrying all over the place.
There's a just unbelievable diversity.
It's not just fish, either.
These are crinoids, sponges, black corals.
There're some more fishes.
Those fishes that you see now are new species.
They're still new species, because I had a video camera instead of my net, so they're still waiting down there for someone to go find them.
But this is what it looks like.
And this kind of habitat just goes on and on and on for miles.
This is Papua, New Guinea.
Now little fishes and invertebrates aren't the only things we see down there.
We also see sharks, much more regularly than I would have expected to.
We're not quite sure why.
What I want you to do now is imagine yourself 400 feet underwater, with all this high-tech gear on your back, you're in a remote reef off Papua, New Guinea, thousands of miles from the nearest recompression chamber, and you're completely surrounded by sharks.
(Video) Diver 1: (In squeaky voice) Look at those ...
Diver 2: Uh, oh ...
Uh, oh!
Audience: (Laughter) (Video) Diver 1: I think we have their attention ...
Richard Pyle: When you start talking like Donald Duck, there's no situation in the world that can seem tense.
(Laughter) So we're down there -- this is at 400 feet.
That's looking straight up, by the way, to give a sense of how far the surface is.
And if you're a biologist and know about sharks, and you want to assess, how much jeopardy am I really in here, there's one question that sort of jumps to the forefront of your mind immediately, which is -- (Video) Diver 1: What kind of sharks?
Diver 2: Silvertip sharks.
Diver 1: Oh.
RP: There are actually three species of sharks here.
The silvertips are the ones with the white edges on the fins, and there're also gray reef sharks and hammerheads off in the distance.
And yes, it's a little nerve-racking.
(Video) Diver 2: Hoo!
That little guy is frisky!
Audience: (Laughter) Now, you've seen video like this on TV a lot, and it's very intimidating.
I think it gives the wrong impression about sharks; they're actually not very dangerous animals.
That's why we weren't worried much and were joking around.
More people are killed by pigs, by lightning strikes, more people are killed at soccer games in England.
There's a lot of other ways you can die.
And I'm not making that stuff up.
Coconuts!
You can get killed by a coconut more likely than killed by a shark.
So sharks aren't quite as dangerous as most people make them out to be.
Now, I don't know if any of you get US News and World Report -- I got the recent issue.
There's a cover story about the great explorers of our time.
The last article is entitled, "No New Frontiers."
It questions whether or not there really are any new frontiers out there, whether there are any true, hardcore discoveries that can still be made.
My favorite line from the article: [... 'discovery' can mean finding a guppy with an extra spine in its dorsal fin."]
I have to laugh; they don't call us fish nerds for nothing.
We actually do get excited about finding a new dorsal spine in a guppy.
But it's much more than that.
I want to show you a few of the guppies we've found over the years.
This one -- you can see how ugly it is.
(Laughter) Even if you ignore the scientific value of this thing, look at the monetary value of this thing.
A couple of these were sold through the aquarium trade to Japan, where they sold for 15,000 dollars apiece.
That's half a million dollars a pound.
Here's another new angelfish we discovered.
This one we first discovered back in the air days -- the bad old air days, when we were doing these kind of dives with air.
We were at 360 feet.
I remember coming up from one of these deep dives and I had this fog, and the narcosis takes a little while to fade away, sort of like sobering up.
I had this vague recollection of seeing this yellow fish with a black spot, and thought, "Damn, I should have caught one -- I think that's a new species."
Eventually, I looked in my bucket.
Sure enough, I had caught one, I just completely forgot.
So this one, we decided to give the name Centropyge narcosis to.
That's its official scientific name, in reference to its deep-dwelling habits.
This is another neat one.
When we first found it, we weren't even sure what family it belonged to, so we just called it the Dr. Seuss fish, since it looked like something from one of those books.
Now, this one's pretty cool.
If you go to Papua, New Guinea and go down 300 feet, you'll see these big mounds.
This may be hard to see, but they're a couple meters in diameter.
If you look closely, you'll see there's a little white and gray fish that hangs out near them.
It turns out this little white fish builds these giant mounds, one pebble at a time.
It's extraordinary to find something like this.
It's not just new species, it's new behaviors, new ecology, all kind of new things.
What I'm going to show you now, quickly, is a sampling of the new species we've discovered.
What's extraordinary is not just the number of species we're finding -- though as you can see, that's pretty amazing; this is only half of what we've found -- what's extraordinary is how quickly we find them.
We're up to seven new species per hour of time we spend at that depth.
If you go to an Amazon jungle and fog a tree, you may get a lot of bugs, but for fishes, there's nowhere in the world you can get seven new species per hour of time.
Now, we've done some back-of-the-envelope calculations, and we're predicting there are probably about 2,000 to 2,500 new species in the Indo-Pacific alone.
There are only five to six thousand known species, so a very large percentage of what is out there isn't really known.
We thought we had a handle on all the reef fish diversity -- evidently not.
I'm going to just close on a very somber note.
At the beginning, I said I'd show you two extraordinary photographs.
This is the second extraordinary photograph I'm going to show you.
This one was taken at the exact moment I was down there filming those sharks.
This was taken exactly 300 feet above my head.
The reason this photograph is extraordinary is because it captures a moment in the very last minute of a person's life.
Less than 60 seconds after this picture was taken, this guy was dead.
When we recovered his body, we figured out what had gone wrong.
He had made a very simple mistake; he turned the wrong valve when he filled his cylinder.
he had 80 percent oxygen in his tank when he should have had 40.
He had an oxygen toxicity seizure and he drowned.
The reason I show this -- not to put a downer on everything -- but I just want to use it to key off my philosophy of life in general, which is that we all have two goals.
The first goal we share with every other living thing on this planet, which is to survive.
I call it perpetuation: the survival of the species and survival of ourselves, And those are both about perpetuating the genome.
The second goal, for those of us who have mastered the first goal -- call it spiritual fulfillment, call it financial success, you can call it any number of different things.
I call it seeking joy, this pursuit of happiness.
So, I guess my theme on this is this guy lived his life to the fullest, he absolutely did.
You have to balance those two goals.
If you live your whole life in fear -- I mean, life is a sexually transmitted disease with 100 percent mortality.
So you can't live your life in fear.
(Laughter) I thought that was an old one!
(Applause) But at the same time, you don't want to get so focused on rule number two, goal number two, that you neglect goal number one.
Because once you're dead, you really can't enjoy anything after that.
So I wish you all the best of luck in maintaining that balance in your future endeavors.
Thanks.
We live in difficult and challenging economic times, of course.
And one of the first victims of difficult economic times, I think, is public spending of any kind, but certainly in the firing line at the moment is public spending for science, and particularly curiosity-led science and exploration.
So I want to try and convince you in about 15 minutes that that's a ridiculous and ludicrous thing to do.
But I think to set the scene, I want to show -- the next slide is not my attempt to show the worst TED slide in the history of TED, but it is a bit of a mess.
(Laughter) But actually, it's not my fault; it's from the Guardian newspaper.
And it's actually a beautiful demonstration of how much science costs.
Because, if I'm going to make the case for continuing to spend on curiosity-driven science and exploration, I should tell you how much it costs.
So this is a game called "spot the science budgets."
This is the U.K. government spend.
You see there, it's about 620 billion a year.
The science budget is actually -- if you look to your left, there's a purple set of blobs and then yellow set of blobs.
And it's one of the yellow set of blobs around the big yellow blob.
It's about 3.3 billion pounds per year out of 620 billion.
That funds everything in the U.K.
from medical research, space exploration, where I work, at CERN in Geneva, particle physics, engineering, even arts and humanities, funded from the science budget, which is that 3.3 billion, that little, tiny yellow blob around the orange blob at the top left of the screen.
So that's what we're arguing about.
That percentage, by the way, is about the same in the U.S. and Germany and France.
R&amp;D in total in the economy, publicly funded, is about 0.6 percent of GDP.
So that's what we're arguing about.
The first thing I want to say, and this is straight from "Wonders of the Solar System," is that our exploration of the solar system and the universe has shown us that it is indescribably beautiful.
This is a picture that actually was sent back by the Cassini space probe around Saturn, after we'd finished filming "Wonders of the Solar System."
So it isn't in the series.
It's of the moon Enceladus.
So that big sweeping, white sphere in the corner is Saturn, which is actually in the background of the picture.
And that crescent there is the moon Enceladus, which is about as big as the British Isles.
It's about 500 kilometers in diameter.
So, tiny moon.
What's fascinating and beautiful ...
this an unprocessed picture, by the way, I should say, it's black and white, straight from Saturnian orbit.
What's beautiful is, you can probably see on the limb there some faint, sort of, wisps of almost smoke rising up from the limb.
This is how we visualize that in "Wonders of the Solar System."
It's a beautiful graphic.
What we found out were that those faint wisps are actually fountains of ice rising up from the surface of this tiny moon.
That's fascinating and beautiful in itself, but we think that the mechanism for powering those fountains requires there to be lakes of liquid water beneath the surface of this moon.
And what's important about that is that, on our planet, on Earth, wherever we find liquid water, we find life.
So, to find strong evidence of liquid, pools of liquid, beneath the surface of a moon 750 million miles away from the Earth is really quite astounding.
So what we're saying, essentially, is maybe that's a habitat for life in the solar system.
Well, let me just say, that was a graphic.
I just want to show this picture.
That's one more picture of Enceladus.
This is when Cassini flew beneath Enceladus.
So it made a very low pass, just a few hundred kilometers above the surface.
And so this, again, a real picture of the ice fountains rising up into space, absolutely beautiful.
But that's not the prime candidate for life in the solar system.
That's probably this place, which is a moon of Jupiter, Europa.
And again, we had to fly to the Jovian system to get any sense that this moon, as most moons, was anything other than a dead ball of rock.
It's actually an ice moon.
So what you're looking at is the surface of the moon Europa, which is a thick sheet of ice, probably a hundred kilometers thick.
But by measuring the way that Europa interacts with the magnetic field of Jupiter, and looking at how those cracks in the ice that you can see there on that graphic move around, we've inferred very strongly that there's an ocean of liquid surrounding the entire surface of Europa.
So below the ice, there's an ocean of liquid around the whole moon.
It could be hundreds of kilometers deep, we think.
We think it's saltwater, and that would mean that there's more water on that moon of Jupiter than there is in all the oceans of the Earth combined.
So that place, a little moon around Jupiter, is probably the prime candidate for finding life on a moon or a body outside the Earth, that we know of.
Tremendous and beautiful discovery.
Our exploration of the solar system has taught us that the solar system is beautiful.
It may also have pointed the way to answering one of the most profound questions that you can possibly ask, which is: "Are we alone in the universe?"
Is there any other use to exploration and science, other than just a sense of wonder?
Well, there is.
This is a very famous picture taken, actually, on my first Christmas Eve, December 24th, 1968, when I was about eight months old.
It was taken by Apollo 8 as it went around the back of the moon.
Earthrise from Apollo 8.
A famous picture; many people have said that it's the picture that saved 1968, which was a turbulent year -- the student riots in Paris, the height of the Vietnam War.
The reason many people think that about this picture, and Al Gore has said it many times, actually, on the stage at TED, is that this picture, arguably, was the beginning of the environmental movement.
Because, for the first time, we saw our world, not as a solid, immovable, kind of indestructible place, but as a very small, fragile-looking world just hanging against the blackness of space.
What's also not often said about the space exploration, about the Apollo program, is the economic contribution it made.
I mean while you can make arguments that it was wonderful and a tremendous achievement and delivered pictures like this, it cost a lot, didn't it?
Well, actually, many studies have been done about the economic effectiveness, the economic impact of Apollo.
The biggest one was in 1975 by Chase Econometrics.
And it showed that for every $1 spent on Apollo, 14 came back into the U.S. economy.
So the Apollo program paid for itself in inspiration, in engineering, achievement and, I think, in inspiring young scientists and engineers 14 times over.
So exploration can pay for itself.
What about scientific discovery?
What about driving innovation?
Well, this looks like a picture of virtually nothing.
What it is, is a picture of the spectrum of hydrogen.
See, back in the 1880s, 1890s, many scientists, many observers, looked at the light given off from atoms.
And they saw strange pictures like this.
What you're seeing when you put it through a prism is that you heat hydrogen up and it doesn't just glow like a white light, it just emits light at particular colors, a red one, a light blue one, some dark blue ones.
Now that led to an understanding of atomic structure because the way that's explained is atoms are a single nucleus with electrons going around them.
And the electrons can only be in particular places.
And when they jump up to the next place they can be, and fall back down again, they emit light at particular colors.
And so the fact that atoms, when you heat them up, only emit light at very specific colors, was one of the key drivers that led to the development of the quantum theory, the theory of the structure of atoms.
I just wanted to show this picture because this is remarkable.
This is actually a picture of the spectrum of the Sun.
And now, this is a picture of atoms in the Sun's atmosphere absorbing light.
And again, they only absorb light at particular colors when electrons jump up and fall down, jump up and fall down.
But look at the number of black lines in that spectrum.
And the element helium was discovered just by staring at the light from the Sun because some of those black lines were found that corresponded to no known element.
And that's why helium's called helium.
It's called "helios" -- helios from the Sun.
Now, that sounds esoteric, and indeed it was an esoteric pursuit, but the quantum theory quickly led to an understanding of the behaviors of electrons in materials like silicon, for example.
The way that silicon behaves, the fact that you can build transistors, is a purely quantum phenomenon.
So without that curiosity-driven understanding of the structure of atoms, which led to this rather esoteric theory, quantum mechanics, then we wouldn't have transistors, we wouldn't have silicon chips, we wouldn't have pretty much the basis of our modern economy.
There's one more, I think, wonderful twist to that tale.
In "Wonders of the Solar System," we kept emphasizing the laws of physics are universal.
It's one of the most incredible things about the physics and the understanding of nature that you get on Earth, is you can transport it, not only to the planets, but to the most distant stars and galaxies.
And one of the astonishing predictions of quantum mechanics, just by looking at the structure of atoms -- the same theory that describes transistors -- is that there can be no stars in the universe that have reached the end of their life that are bigger than, quite specifically, 1.4 times the mass of the Sun.
That's a limit imposed on the mass of stars.
You can work it out on a piece of paper in a laboratory, get a telescope, swing it to the sky, and you find that there are no dead stars bigger than 1.4 times the mass of the Sun.
That's quite an incredible prediction.
What happens when you have a star that's right on the edge of that mass?
Well, this is a picture of it.
This is the picture of a galaxy, a common "our garden" galaxy with, what, 100 billion stars like our Sun in it.
It's just one of billions of galaxies in the universe.
There are a billion stars in the galactic core, which is why it's shining out so brightly.
This is about 50 million light years away, so one of our neighboring galaxies.
But that bright star there is actually one of the stars in the galaxy.
So that star is also 50 million light years away.
It's part of that galaxy, and it's shining as brightly as the center of the galaxy with a billion suns in it.
That's a Type Ia supernova explosion.
Now that's an incredible phenomena, because it's a star that sits there.
It's called a carbon-oxygen dwarf.
It sits there about, say, 1.3 times the mass of the Sun.
And it has a binary companion that goes around it, so a big star, a big ball of gas.
And what it does is it sucks gas off its companion star, until it gets to this limit called the Chandrasekhar limit, and then it explodes.
And it explodes, and it shines as brightly as a billion suns for about two weeks, and releases, not only energy, but a huge amount of chemical elements into the universe.
In fact, that one is a carbon-oxygen dwarf.
Now, there was no carbon and oxygen in the universe at the Big Bang.
And there was no carbon and oxygen in the universe throughout the first generation of stars.
It was made in stars like that, locked away and then returned to the universe in explosions like that in order to recondense into planets, stars, new solar systems and, indeed, people like us.
I think that's a remarkable demonstration of the power and beauty and universality of the laws of physics, because we understand that process, because we understand the structure of atoms here on Earth.
This is a beautiful quote that I found -- we're talking about serendipity there -- from Alexander Fleming: "When I woke up just after dawn on September 28, 1928, I certainly didn't plan to revolutionize all medicine by discovering the world's first antibiotic."
Now, the explorers of the world of the atom did not intend to invent the transistor.
And they certainly didn't intend to describe the mechanics of supernova explosions, which eventually told us where the building blocks of life were synthesized in the universe.
So, I think science can be -- serendipity is important.
It can be beautiful.
It can reveal quite astonishing things.
It can also, I think, finally reveal the most profound ideas to us about our place in the universe and really the value of our home planet.
This is a spectacular picture of our home planet.
Now, it doesn't look like our home planet.
It looks like Saturn because, of course, it is.
It was taken by the Cassini space probe.
But it's a famous picture, not because of the beauty and majesty of Saturn's rings, but actually because of a tiny, faint blob just hanging underneath one of the rings.
And if I blow it up there, you see it.
It looks like a moon, but in fact, it's a picture of Earth.
It was a picture of Earth captured in that frame of Saturn.
That's our planet from 750 million miles away.
I think the Earth has got a strange property that the farther away you get from it, the more beautiful it seems.
But that is not the most distant or most famous picture of our planet.
It was taken by this thing, which is called the Voyager spacecraft.
And that's a picture of me in front of it for scale.
The Voyager is a tiny machine.
It's currently 10 billion miles away from Earth, transmitting with that dish, with the power of 20 watts, and we're still in contact with it.
But it visited Jupiter, Saturn, Uranus and Neptune.
And after it visited all four of those planets, Carl Sagan, who's one of my great heroes, had the wonderful idea of turning Voyager around and taking a picture of every planet it had visited.
And it took this picture of Earth.
Now it's very hard to see the Earth there, it's called the "Pale Blue Dot" picture, but Earth is suspended in that red shaft of light.
That's Earth from four billion miles away.
And I'd like to read you what Sagan wrote about it, just to finish, because I cannot say words as beautiful as this to describe what he saw in that picture that he had taken.
He said, "Consider again that dot.
That's here.
That's home.
That's us.
On it, everyone you love, everyone you know, everyone you've ever heard of, every human being who ever was lived out their lives.
The aggregates of joy and suffering thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every superstar, every supreme leader, every saint and sinner in the history of our species, lived there, on a mote of dust, suspended in a sunbeam.
It's been said that astronomy's a humbling and character-building experience.
There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world.
To me, it underscores our responsibility to deal more kindly with one another and to preserve and cherish the pale blue dot, the only home we've ever known."
Beautiful words about the power of science and exploration.
The argument has always been made, and it will always be made, that we know enough about the universe.
You could have made it in the 1920s; you wouldn't have had penicillin.
You could have made it in the 1890s; you wouldn't have the transistor.
And it's made today in these difficult economic times.
Surely, we know enough.
We don't need to discover anything else about our universe.
Let me leave the last words to someone who's rapidly becoming a hero of mine, Humphrey Davy, who did his science at the turn of the 19th century.
He was clearly under assault all the time.
"We know enough at the turn of the 19th century.
Just exploit it; just build things."
He said this, he said, "Nothing is more fatal to the progress of the human mind than to presume that our views of science are ultimate, that our triumphs are complete, that there are no mysteries in nature, and that there are no new worlds to conquer."
Thank you.
(Applause)