HUNTING THE ELEMENTS

PBS Airdate: April 4, 2012

DAVID POGUE (Technology Guru): Why do bombs go boom?

You have created fire!

I could feel that puppy!

How much gold is in 400 tons of dirt?

MIKE LASSITER (Refinery Supervisor, Barrick Gold Corporation): There's about a million and a half dollars there.

DAVID POGUE: Oh, man! What's that gorilla doing there? And how come rare earths, the metals that make our gadgets go, aren't that rare at all?

Watch out with the hammer. What are you…?

LAWRENCE L. "LARRY" JONES (The Ames Laboratory): Oh yeah. Cerium, lanthanum, praseodymium.

DAVID POGUE: We live in a world of incredible material variety.

Yet everything we know, the stars, the planets and life, itself, comes from about 90 basic building blocks,…

You have a periodic table table.

…all right here, on this remarkable chart: the periodic table of the elements.

It's a story that begins with the Big Bang and eventually leads to us.

Manganese! Go!

And we're made, almost entirely, of just a handful of ingredients, including one that burns with secret fire inside us all.

Join me as I explore the basic building blocks of the universe…

Oh!

LINDSAY BAKER (Gatorade Sports Science Institute): …as hard as you can. You can do it.

DAVID POGUE: …from some of the most common, like oxygen,…

LINDSAY BAKER: How do you feel at this stage?

DAVID POGUE: …to the least—manmade elements that last only fractions of a second; strange metals with repellant powers;…

And you're saying that this will repel the sharks. Oh, my gosh! Uh!

…poisonous gases,…

Isn't chlorine deadly?

THEO GRAY (Chemist and Author): Absolutely.

DAVID POGUE: …in stuff we eat every day. And now, we can even see what they're made of.

The dots are actual atoms?

If you're like me, you care about the elements and how they go together,…

Oh, the humanity!

…because, more than ever,…

Incoming neutron!

…matter, matters.

HARRIET HUNNABLE (Managing Director, CME Group): Copper is king.

DAVID POGUE: Commodities! Copper at 80 cents a pound.

Can we crack the code to build the world of the future? Join me on my Hunt for the Elements, right now, on NOVA.

Far from prying eyes, the ground erupts; heavy equipment moving millions of tons of earth in search of something: a secret, deep underground.

I'm David Pogue.

I've managed to talk my way into this hidden lair.

JOHN TAULE (Miner, Barrick Gold Corporation): …probably almost a mile from where we first came in.

DAVID POGUE: Boy, I hope I can talk my way out.

MIKE LASSITER: This area, here, has been backfilled.

DAVID POGUE: They tell me that so much money flows out of this place, it's like a gold mine. Wait a minute.

It is a gold mine! But where's the gold?

It turns out that nature has concealed thousands of pounds of the stuff under billions of cubic feet of earth. By digging, these guys are hoping to strike it rich.

But that's not why I'm here. I'm on a quest to understand the basic building blocks of everyday matter. They're called the elements. These symbols represent the atoms that make up every single thing in our universe: 118 unique substances arranged on an amazing chart that reveals their hidden secrets to anyone who knows how to read it.

It's a journey that dives deep into the metals of civilization, marvels at the mysteries of the extremely reactive, reveals hidden powers and harnesses secrets of life, from hydrogen to uranium and beyond.

I'm starting with one of humanity's first elemental loves: gold; symbol Au. Like all elements, gold is an atom that gets its identity from tiny particles: positively charged protons in the nucleus, balanced by negatively charged electrons all around, plus neutrons, which have no charge at all.

Gold has been sought since ancient times, yet all the gold ever mined would fit into a single cube about 60 feet on a side. Gold is unique among the metals. It doesn't rust or tarnish. It's virtually indestructible, yet also soft and malleable. It was a sacred material to ancient people, and it's never lost its luster.

The problem is it's exceedingly rare stuff in the earth's crust, and it's getting harder to find all the time.

Here, at the Cortez Mine, in Nevada, high-tech prospectors are moving mountains, closing in from above and below.

This rock face is about a quarter mile below the surface, and, according to John Taule, it's loaded with gold, somewhere.

And what would it look like? Like yellow, metallic streaks in the walls?

JOHN TAULE: No, it's really hard to tell from the rock, because it's microscopic, you can't see the gold.

DAVID POGUE: The gold is microscopic?

JOHN TAULE: Yes, you can't see it with the naked eye.

DAVID POGUE: So, we're way past the days of finding big gold nuggets sticking out of the wall, going "Hey, Bob, I got one here!" We're past that now, huh?

JOHN TAULE: That's correct.

DAVID POGUE: Which raises a question: if the gold is invisible to the naked eye, how do they even know if they're digging in the right place?

That's where Gayle Fitzwater and the assay team come in. Every day she receives hundreds of samples of earth taken from the mine. Her job is to figure out how much gold is in them there rocks.

To get at the color, it has to be crushed,…

Do you want ice cream with this?

…shuffled like a deck of cards,…

I think I've seen one of these machines at Starbucks.

…then pulverized to the consistency of baby powder.

I don't see any more rocks in here, but the bad news is, I don't see any gold in here, either. The good news is that we haven't finished; there may be still gold hiding in the mix.

The sample, mixed with a lead oxide powder, goes into a furnace heated to 2,000 degrees. It's a 500-year-old process called a fire assay. Using extreme heat, gold atoms are gradually coaxed away from the powdered rock.

So, after all that pulverizing and crushing and weighing and firing, what we're left with is this? These little teacups?

GAYLE FITZWATER (Laboratory Supervisor, Barrick Gold Corporation): What you're going to be able to see in here is a gold bead that was recovered from that sample that you crushed.

DAVID POGUE: Um, no.

GAYLE FITZWATER: Okay, come on.

DAVID POGUE: This is like the emperor's new teacup. There's nothing in here except that little tiny piece of dust.

GAYLE FITZWATER: That's a piece of gold. That actually weighs about a half a milligram, and…

DAVID POGUE: So all that work gave you only a half a milligram of gold?

GAYLE FITZWATER: …it equals out to about one ounce per ton.

DAVID POGUE: An ounce of gold for every ton of rock?

GAYLE FITZWATER: That's right, and…

DAVID POGUE: That's a terrible business. You'll never make any money.

GAYLE FITZWATER: …when you went in the mine, and you were able to see the trucks that we had, those are 400-ton haul packs. If you had 400 tons of material at one ounce per ton,…

DAVID POGUE: …four hundred tons and one ounce of gold for each ton. At that rate, that's 25 pounds of gold for every truck.

GAYLE FITZWATER: And at $1,800 an ounce…

DAVID POGUE: Eighteen hundred dollars times…720,000 bucks a truck! This is a fantastic business! How do I get in on this?

Turns out that an ounce per ton is pretty much optimal for the underground mine.

The surface mine produces less, about half an ounce per ton.

To see what it takes to get something bigger than that tiny bead, I visit the processing plant where the ore ends up.

Just another day in the gold refinery.

Here too, extraction begins with crushing, in these huge tumblers. And that sets the stage for the trickiest step, coaxing the microscopic gold out of the rocky ore.

About three quarters of the elements are metals, and gold is one of the most standoffish. How an atom reacts chemically depends on how willing it is to share electrons with others, and gold is not very social. Like Greta Garbo, it "vants" to be alone.

So do other so-called "noble" metals: silver, platinum, palladium, osmium and iridium, all located in the same quiet neighborhood of the periodic table.

Using cyanide to react with the gold allows them to gradually reduce 40,000-gallon tanks of pulverized sludge to this: three trays full of mud?

But there's not gold in here, is there?

MIKE LASSITER: There's a little bit of carbon that's mixed in with this that's changed the color on it, but I assure you that when we melt it and pour it down, Dave, we're going to have gold.

DAVID POGUE: All right, and how much gold, like, how many gold bars will this array make?

MIKE LASSITER: This should produce about a bar and a half.

DAVID POGUE: All right. And it all derived from one 40,000-gallon batch of solution?

MIKE LASSITER: Right.

DAVID POGUE: So, 40,000 gallons got distilled down to this, and that will get distilled down to a bar and a half?

MIKE LASSITER: Right, exactly.

DAVID POGUE: Wow.

The golden mud goes into a 2,000-degree induction furnace, along with a white powder called flux, chemicals that prevent the molten gold from reacting with or sticking to anything.

This is the first time an outsider has been allowed to pour gold.

Just call me King Midas.

I'm not sure they entirely know what they are doing, but they are going to let me pour the gold into a gold bar mold. If it goes over 70 pounds, it's a reject. They'll have to throw it away or just let me take it home in my luggage.

So, you know, I'll, I'll do my best not to spill. There's a lot of money at stake here. Here it comes, hot gold. Get your hot gold here.

Right there. It's a gold bar, ladies and gentlemen. It's been my pleasure. See you next week! Perfect job.

Final steps: cool and clean the bars, stamp them with their unique serial numbers and their weights.

So this is it, the proverbial gold bars. And you know what? They're still warm.

MIKE LASSITER: They're still warm. Hot off the press.

DAVID POGUE: Can I pick one of these up? It's not "May I?" It's "Can I?" Oh, man! This thing…so, so this is, what, 70 pounds?

MIKE LASSITER: It's about 60 pounds.

DAVID POGUE: Sixty pounds?

MIKE LASSITER: Yes.

DAVID POGUE: Oh, it's nothing. And, and about how much value here?

MIKE LASSITER: There is about a million and a half dollars there, Dave.

DAVID POGUE: Oh, man. Mike, what's that gorilla doing there?

They are deceptively heavy. Only a few natural elements have greater density than gold: rhenium, platinum, iridium and osmium.

Mike tells me that each bar represents about a million pounds of rock that had to be moved and processed. Eight bars, $12 million, sitting on this unassuming little table. What a transformation.

Of all the elements that touch our lives, nothing drives humankind to acts of love or destruction like gold. It is, perhaps, the most emotional of the elements.

But two rows above gold is another metal of antiquity that looms large in our lives: copper; symbol Cu; atomic number 29—29 protons, 29 electrons.

The ancients first learned how to heat rocks to extract copper, at least 7,000 years ago.

And, today, it's one of the most widely bought and sold metals in the world. The New York Mercantile Exchange is a vital hub in the global metals market, which is pretty good news for me.

At least, I thought so.

ED MOSES (Director, National Ignition Facility): Sorry, sir, you can't come in with this.

DAVID POGUE: I thought this is a copper exchange. I'm here to exchange some copper.

ED MOSES: I'm sorry, that's not allowed on the floor. You can't come in with this.

DAVID POGUE: Seriously? The only business that they're willing to do here is to buy or sell copper futures? Like, who would fall for that?

ANTHONY GRISANTI (Commodities Trader): Oh, this is an old, old business. This goes back to the 1800s, the late 1800s, where farmers were looking, actually, for money to plant their next year's crops. So what the farmers would do is they would say, for example, "David, you loan me some money, okay? And then, in the future, I will sell you that crop that I planted for this amount of dollar."

So what I'm doing is I'm selling you the right to buy or sell my future crops.

DAVID POGUE: So this crazy high-tech thing began as a glorified farmer's market?

HARRIET HUNNABLE: In fact, this exchange, in New York, started as a butter and cheese exchange, on Harrison Street.

DAVID POGUE: Is it safe to say there's no cheese pit here somewhere?

Uh, gruyere, gruyere! Cheddar, cheddar!

HARRIET HUNNABLE: David, you have to go to Chicago for that.

DAVID POGUE: They still do that?

HARRIET HUNNABLE: Yeah, they still trade agricultural products.

DAVID POGUE: I would think that there would be trading markets like this for gold and silver and platinum, and things that are valuable, but copper? Come on, it's like pennies, it's like…

HARRIET HUNNABLE: Copper is king, okay? Copper is used for everything. It's a really vital metal. We use it for infrastructure; we use it for electronic goods. I can hardly think of anything that doesn't have either a tiny bit of copper or lots of copper. I love copper. I do. I do.

DAVID POGUE: I'm getting that.

Harriet tells me that the copper market is huge. Traders in New York, London and Shanghai buy and sell more than 20 million tons a year. Copper is in wire, electronics and computer chips, plumbing and other building materials. It's so important that the rise and fall of copper prices provide a snapshot of the health of the entire world economy. When times are bad, copper prices tumble, and when times are good, they soar. Some say it should be called "Dr. Copper," because it's the only metal with a Ph.D. in economics.

Copper has been prized for millennia for its unique properties: it conducts electricity better than any metal except silver; it's malleable and has a moderate melting temperature; it even scares away bacteria.

These guys can trade their copper futures; I've got to unload my copper today.

Commodities! Get your commodities! Got copper at 80 cents a pound. Anybody? Anybody?

Copper alone is impressive stuff, but when ancient metallurgists combined it with another element, they invented a much tougher material that went on to conquer the world. That secret ingredient? Tin; symbol Sn; atomic number 50—50 protons and 50 electrons.

Tin added in small amounts to copper makes bronze, the first manmade metal alloy. Bronze helped to spur global trade, and, once forged into tools and weapons, it played a defining role in the empires of antiquity. Bronze named an entire age of human civilization. And even today, it's still hanging around.

This is The Verdin Company, a 170-year-old family-run business in Cincinnati, Ohio.

I'm here because they're about to cast several bells. Even with all the other modern materials available, they still choose bronze. I want to know why. Hasn't something better come along, after all these years?

Ralph Jung offers to make the case for bronze.

RALPH JUNG (Bell Maker, The Verdin Company): This is our pattern that we're going to use to actually make the form in the sand.

DAVID POGUE: So this looks like a finished bell. This isn't a bell?

RALPH JUNG: Yes, it does. This is just the pattern. Yeah. It's made out of aluminum, so it's real easy to handle.

DAVID POGUE: Well, what's wrong with that? Aluminum's good: aluminum doesn't rust; aluminum's light.

RALPH JUNG: You're right. It doesn't.

DAVID POGUE: Why don't you make the bells out of this?

RALPH JUNG: Well, the sound. It doesn't have that lasting ring. And it just…

DAVID POGUE: You don't like how that sounds?

RALPH JUNG: Not really. It sounds kind of tinny, also.

DAVID POGUE: Hey, thanks a lot, buddy.

RALPH JUNG: Well, you know.

DAVID POGUE: I practiced.

RALPH JUNG: We'll show you what a real bell sounds like.

DAVID POGUE: The quality of the sound depends on the atomic structure of the material.

In pure metals, the atoms are arranged in orderly rows and columns. Each atom gives up some of its electrons to create a kind of sea of these randomly moving charged particles.

It's these free-flowing electrons that make metals conductive. When placed in a circuit, the negatively charged particles line up and flow as an electric current.

The sea of electrons also creates flexible, metallic bonds among the atoms. In copper, they can slide past each other easily, which makes it relatively soft and easy to dent, not right for a bell. That's why Verdin uses stiffer stuff.

RALPH JUNG: So, we'll put this down into here.

DAVID POGUE: Ralph places the form into a circular steel sleeve, then fills the space around it with a mixture of sand and epoxy, to withstand the searing heat of the hot metal.

When this company started, they used a mixture of horsehair, manure and just about anything else that would hold a shape without burning, but the goal was the same: to create a hollow shape that follows the inner and outer perimeter of the bell.

Once he removes the aluminum and joins the two halves, a bell-shaped space remains on the inside, ready to accept the molten bronze.

RALPH JUNG: And what we have here, David, is the bronze ingots that we use to put in the furnace. As you can see, they're, they've got a little bit of heft to them.

DAVID POGUE: Yeah, it's like…

RALPH JUNG: They average about 20 pounds. That's a, that's a mixture, actually, of 80 percent copper and 20 percent tin. And what we have here is the tin in a raw form. This is how it comes out of the ground. This is from Malaysia.

DAVID POGUE: Okay.

RALPH JUNG: And we have a chunk of copper the way it comes out of the ground. And that's from South Africa.

DAVID POGUE: So, that's the recipe for bronze?

RALPH JUNG: Exactly.

DAVID POGUE: So, you've got copper plus tin equals bronze.

RALPH JUNG: Equals bronze, yeah.

DAVID POGUE: Why couldn't you use one of those metals by themselves? Why don't you make bells out of just copper?

RALPH JUNG: If it was all copper, it would, first of all, be too soft, and we wouldn't get that sound that we want from a bell. Tin with copper gives us that hardness.

DAVID POGUE: Adding tin to copper during melting changes the properties of the metal. The larger tin atoms restrict the movement of the copper atoms, making the material harder.

A blow causes the atoms to vibrate, but the tin prevents them from moving too far out of position. Tin is good for a bell, but only in the right proportion.

This is what can happen if the amount of tin isn't right. No one is certain why the Liberty Bell cracked, but a chemical analysis indicated there was too much tin and perhaps other impurities in the bronze. The crack could have been caused by the way the atoms were arranged within the metal.

Too much tin, and the copper atoms can't move at all. One good whack and…

When the bronze has reached the proper temperature, 2,200 degrees Fahrenheit, it's time to pour.

Is there any danger involved in this process?

RALPH JUNG: Well, if you consider getting burned a danger, yes there is.

DAVID POGUE: During the pour, speed is of the essence. If the metal is allowed to cool, flaws could develop, ruining the bell.

Even though the foundry has the technology to precisely control the temperature, and Ralph and his team have decades of experience, bronze remains unpredictable.

Out of every hundred bells they pour, 20 or 30 will fail.

That was quite a process. I appreciate your letting me help out like that.

RALPH JUNG: I think we got three successful bells out of this, but anything can go wrong, so you just don't know, until after you open up the molds and see what you've got.

DAVID POGUE: The bells have to cool for 24 hours, so it's the next day before we can find out if they'll be making music or ending up as scrap.

So, what am I going to see inside? A gleaming chrome, silver magnificent church bell ready for hanging?

RALPH JUNG: Actually no, you're going to see…I like to refer to them as a newborn baby. They come out kind of ugly and not so pretty, but they clean up really well.

DAVID POGUE: Bum…bum…bum… bum…bum! Wow, I can feel, I can feel waves of heat coming off of this.

RALPH JUNG: Yes, it's still quite warm.

DAVID POGUE: Is it, is it touchable?

RALPH JUNG: Yes, it's touchable.

DAVID POGUE: Oww! Speak for yourself, dude!

And what happens to a carefully crafted sand mold? It's history.

Is this an actual bell that you can actually sell to somebody?

RALPH JUNG: Oh, yes. Yes, we're going to. This will be on the market very soon.

DAVID POGUE: So I really do need to not chip it.

RALPH JUNG: That would be good.

DAVID POGUE: So what about all this black sooty stuff?

RALPH JUNG: So that's going to have to be cleaned off of there.

DAVID POGUE: You got some kind of big hydraulic…?

RALPH JUNG: Actually no, I've got this.

Well, that was a big waste of time. You missed a big spot over here. I, I guess that's okay for a rookie.

DAVID POGUE: Well thank you so much, Ralph.

And now, for the moment of truth: will this bell be good enough to sing?

What time is it? Time to celebrate the millennia-old tradition of bronze.

Our bell resonates with a beautiful tone, and it takes many seconds for the note to die out, thanks to the interplay between copper and tin.

Even the best bell makers can't know whether their bronze will be too stiff or too soft, until they pour a bell and strike it.

I wonder, though, if there's a more scientific way to evaluate the metal.

To find out, I'm taking a piece of it to David Muller, at Cornell University.

He's offered to show me how the atoms in our bronze stack up, literally.

I brought you a couple of hunks of bronze, uh, one of which was knocked off of a bell when it was done and one of which is un-poured. And I wouldn't mind taking a look at these under your magic microscope.

DAVID MULLER (Cornell University): Okay. Now, this is actually a lot of material. I need an area about the size of a farm, and you've given me the whole of the United States. So we're going to cut it down a little bit.

Now watch out, it's hot.

DAVID POGUE: It's what? Ow!

First, a polishing wheel gives the bronze a mirror-like finish. Then the sample is inserted into a powerful electron microscope. David tells me that when we reach full magnification, we will have images of the actual atoms in the bronze, something few people have ever seen.

Frankly, it seems a little farfetched.

So what's in there right now? What are we looking at?

DAVID MULLER: So, we have a piece of the bronze that we cut earlier, very similar to this one.

DAVID POGUE: Now, I have to say, this microscope is not especially impressive. I mean, I'm seeing the entire circle like I'm just wearing a pair of reading glasses or something.

DAVID MULLER: This is like having a map of the United States, and eventually we want to zoom in, and we want to pick out one car, parked somewhere in the U.S.

DAVID POGUE: We'll have to zoom in a hundred million times to see an atom.

To understand the scale, imagine if I were floating in space, 2,000 miles above the earth, looking down at the United States. Zooming in a hundred million times would allow me to pick out, not just a car, but a bug, crawling in the grass next to it.

So we can zoom in from here?

DAVID MULLER: Absolutely.

DAVID POGUE: How do you do that?

DAVID MULLER: So, there's the zoom button.

DAVID POGUE: The big knob, labeled "Magnification?"

DAVID MULLER: Absolutely. So crank up the mag, and let's see what happens as you zoom in.

DAVID POGUE: Wait! I see a little tiny cartoon sign that says, "Welcome to Whoville!"

To see atoms, we need to find an interesting region to sample. Now it's starting to look like an alien surface.

DAVID MULLER: Right. Now what we're actually starting to see is the microstructure of the grains in that bronze. And the brighter colors are things that contain more tin, and the things with less tin are the things that are slightly darker.

DAVID POGUE: Oh, my gosh, that is so cool.

The microscopic structure of metals is not uniform. Small features, called grains, become visible. Boundaries between grains are actually defects in the orderly arrangement of the atoms.

So you can't see atoms with this microscope?

DAVID MULLER: We can get almost all the way there, but not quite.

DAVID POGUE: Okay.

DAVID MULLER: And to look at atoms, we're going to need a bigger machine.

DAVID POGUE: Do you have one?

DAVID MULLER: We certainly do.

DAVID POGUE: This huge thing? This giant room-sized thing in a shipping container?

And why is it draped in shipping crate material?

DAVID MULLER: Those are acoustic blankets. They are meant to absorb and reflect sound, because the microscope itself is so sensitive that if you were to talk, just the pressure wave from your voice is going to, is going to give enough mechanical vibration to shake this thing around. We only have to shake things by an atom for the image to vanish.

DAVID POGUE: So our little piece of bronze that we've dug out of the first machine, is now the little black disc there?

DAVID MULLER: Well, that's the three millimeter support disc. The actual bronze chip itself is about a hundredth the thickness of a human hair. It's too small for us to see, so we have to mount it on a carrier grid, so we can handle it.

DAVID POGUE: Oh, so you've, you've essentially put it on a little plate.

DAVID MULLER: That's right.

DAVID POGUE: Are you telling me that I can see individual atoms of my piece of bell?

DAVID MULLER: That's correct.

DAVID POGUE: Scientists have understood, since the early 20th century, that metals are crystals; that is, they have an orderly arrangement of atoms.

By bombarding samples with x-rays they were able to create shadowy images of that crystal structure, but the idea that we might one day see actual atoms was beyond imagination.

If David's microscope is powerful enough, we should see regular rows of copper atoms with tin atoms packed in between. Or so the theory predicts.

The dots are atoms?

DAVID MULLER: That's right. Each, each individual dot is an atom.

DAVID POGUE: We are seeing actual atoms in my little bell piece?

DAVID MULLER: The bright ones, those are the tin atoms, and the slightly darker ones, those are the copper atoms.

DAVID POGUE: And, and isn't it kind of like a mind-blower that we're actually looking at actual atoms? I mean, isn't this a historic technological achievement?

DAVID MULLER: Every time people see that for the first time, they get really excited.

DAVID POGUE: To actually see atoms…amazing!

Well, what can we learn about this? Like, like, for one thing, I notice they're really, really grid-like. They're, they're like a little aerial photo of a planned community.

DAVID MULLER: That's actually the stacking of the atoms in the material. The pattern that it orders into, that is the crystal structure, directly.

DAVID POGUE: David tells me we got very lucky. The atoms in our bronze are unusually well ordered. Our bell makers must be true masters of their craft.

Well, thanks for my tour into the, to the unseen and to what used to be the pure, purely theoretical. I can't believe I can now put on my resume that I've seen atoms. Thanks for the tour!

DAVID MULLER: It was a pleasure.

DAVID POGUE: This amazing ability to see atoms has opened up new worlds for scientists. Muller's lab has successfully captured many other images of atoms in gold and computer chips, oxygen, powerful magnets and even glass.

But, even so, they've barely scratched the surface, because they can discern only the outermost boundaries around atoms. The interior is 10,000 times smaller. If the outer boundary of a hydrogen atom, where the electron is found, were enlarged to be two miles wide, about the size of a city, the single proton in its nucleus would be the size of a golf ball.

It's here we find elements at their most elemental, because every nucleus contains protons, and it's the number of protons that determines what kind of element the atom is.

One proton is hydrogen; two protons, helium; three protons, lithium; four protons, beryllium; all the way up to element 118, with 118 protons.

The number of protons is called the atomic number and it's the fundamental organizing principle of every table of the elements, including this one.

Wow. This is cool. You have a periodic table table.

THEO GRAY: It's called the periodic table, why do people keep putting them on the wall?

DAVID POGUE: Every high school student has seen the elements chart, but author Theo Gray's version is unique: handmade, with each element's identity card meticulously carved into the wood.

But, I have to say, I've never completely gotten it right. They're filled with stats and figures that don't make any sense to the ordinary person.

Theo gives me a refresher.

THEO GRAY: You've got the name of the element. You've got the atomic symbol.

DAVID POGUE: Ca for calcium.

THEO GRAY: Calcium.

You've got the atomic number, which is the number of protons in the nucleus of each atom of that element. It's probably the most important thing on this tile.

DAVID POGUE: So where's gold?

THEO GRAY: Gold's right there, number 79.

DAVID POGUE: Okay, so here's a classic example. They would do a much better job marketing this table if the name and the symbol matched. Gold doesn't even have Au in it.

THEO GRAY: The symbol is based on the Latin name aurum. And if you think about it, the name of each element is the least important piece of information you could possibly have. What matters about elements is that they are real physical substances with properties and things you can do with them.

DAVID POGUE: Theo makes the point by putting me in touch with the real deal.

Oh, I see what you've done.

To make the entire table less abstract, he invites me to lay out the rest of his collection of pure elements.

Well, this is really pretty amazing. This is a visual representation of every single element that makes up this entire planet and everything on it.

Then Theo reminds me of something I'd forgotten. As we can clearly see, more than 70 percent of the elements on the table are metals, shiny, malleable materials that conduct electricity.

THEO GRAY: There's, sort of, a diagonal line here. Everything from here on over, including the bottom part, is all metals. Everything from here on over is non-metals. And down the middle are these, kind of, halfway in between things, which include, for example, semiconductors, like silicon.

DAVID POGUE: Silicon. Right.

I have to say many of these elements look the way you would think—gold looks like gold, silver looks like silver—but not all of them. The one I was looking at, in particular, was calcium. Most people probably think of calcium as white and chalky, you know? It's bone, it's chalk, it's, uh, it's milk. But this is a silver, shiny metal.

This is when Theo's collection starts to get really interesting, when he pairs the pure elements with their more familiar forms. Like pure calcium metal, combined with other elements to make bone; bismuth, in stomach medicine; bromine, in soda; and even this element, hiding out in collectible Fiesta® ware. This bowl, from the 1930s, gets its orange color from uranium, and it's actually dangerously radioactive.

Theo's table and his remarkable collection make a powerful point. From about 90 elements found on earth, nature and man have derived millions of different substances that make our world. But, to me, there's something even more amazing: the table organizes the elements by atomic number, that is, the number of protons in each atom, yet the table's creator—a 19th-century Russian chemistry professor, named Dmitri Mendeleev—knew nothing about protons or atomic numbers.

Even the atom itself hadn't been discovered.

To understand how he cracked the code of the table, I've come to St. Petersburg, Russia, to the State University and to Mendeleev's apartment and office. In the late 1860s, at this very desk, Mendeleev set out to discover the underlying order to the elements.

In one often repeated story, Mendeleev is said to have created 63 cards, one for each of the elements known at the time. He distinguished them, not by atomic number, but by atomic weight.

So he didn't know about atoms, but isn't this the atomic weight? How does he know the weight, if he doesn't know about atoms?

IGOR DMITRIEV (Director, Mendeleev Museum): It's not in grams or pounds or kilograms. In the 19th century, they did it like this: they compared the weights of different elements to the lightest, hydrogen. So when they say oxygen is 16, that means 16 times the weight of hydrogen.

DAVID POGUE: Nineteenth-century scientists relied on relative weight to order the elements.

Imagine if you have two containers, one full of red marbles, one full of blue marbles. If both contain the same number of marbles, but the blue container weighs twice as much, you can infer that the blue marbles weigh twice as much as the red marbles, even if you can't see the marbles at all.

Early chemists devised clever ways of calculating the weights of elements, even gases, relative to the lightest one: hydrogen.

So the chemists knew that different elements have different weights. But why, why not just one big line forever?

IGOR DMITRIEV: Mendeleev decided that he would arrange them by weight, but also by family.

DAVID POGUE: This is one of Mendeleev's charts. You can see hydrogen sticking out, just as it does today. The families he knew are now arranged in columns. This one has the metals—lithium, sodium and potassium—that explode in water. Next door, calcium and magnesium, which also react with water.

This big block in the middle are metals that are safe to handle, like nickel, iron, zinc and gold.

As we go to the right, the elements become less metallic. These columns are headed by boron, carbon and nitrogen. In this neighborhood, some elements conduct electricity, some don't, and some can't make up their minds.

But next door is a more volatile crowd, headed by oxygen and fluorine.

The table gets its shape from the properties of the elements, like relative weight, conductivity and reactivity. It's true today, as it was in Mendeleev's time.

Though his chart displayed only the 63 elements known at the time, his understanding of the family properties was so strong he was able to leave gaps in his chart, bold predictions of elements yet to be discovered. And when they were eventually found, they proved completely consistent with his descriptions.

Mendeleev lived until 1907, long enough to see three gaps filled by the discoveries of scandium, gallium and germanium.

Since his death, dozens of new elements have been discovered, and incredibly, his chart perfectly accommodates all of them, including an entire group that fits neatly onto the end of the table: the noble gases.

Where does that term "noble gases" come from? Are they nobility? Do they rush to rescue maidens?

THEO GRAY: No, you're thinking of heroes. They are like nobility in the sense that they don't mix with the riffraff. They don't like to react with any other elements.

By and large, it's not possible to form compounds with them.

DAVID POGUE: Well, it's a shame for your collection that they are gases, because you've got big blanks here. Oh, ho, ho, ho!

The noble gases, like neon and argon, pose a problem for chemists who prefer their elements to join forces and react with each other. You can run an electric current through them, excite their electrons and get pretty colors—which is how neon lights work—but the noble gases don't react.

They pretty much refuse to combine with other elements.

THEO GRAY: Being an inert gas, being unwilling to mix with the other elements, react with them, this is a very clear-cut distinction that sets apart this particular column from all the others in the periodic table.

DAVID POGUE: So why are these guys so aloof? As it turns out, protons may determine the identity of an element, but electrons rule its reactivity. And reactivity is a shell game.

Here's how the game is played.

Imagine that these balls are electrons, and the target is an atom. Electrons don't just pile on around the nucleus. As with skee-ball, where you land, relative to the center counts.

Oh come on!

The electrons take up positions in what can be thought of as concentric shells. The first shell maxes out at just two electrons, the next holds eight, then it goes up to eighteen. An atom with eight electrons in its outer shell makes one happy, satisfied atom.

And noble gases come pre-equipped with completely satisfied shells.

And is this the only column like that?

THEO GRAY: It's the only column where all the shells are completely filled.

DAVID POGUE: But what about the column just before those stable noble gases? They are called the halogens. They have an outer shell that needs just one more electron to be full. And they'll grab it any way they can. The group includes fluorine and bromine, but the most notorious is chlorine: 17 protons surrounded by 17 electrons, arranged in three shells of two, eight and seven, one short of being full.

It's that extra electron chlorine will get any way it can, sometimes with violent results. That's why chlorine gas was used as a deadly poison in World War One.

THEO GRAY: Chlorine, I mean, this is nasty stuff. This will take electrons from kittens. It'll go and steal an electron from off the water in your lungs and turn it to hydrochloric acid, because it really wants an electron.

DAVID POGUE: Yeah, maybe I'll leave that where it was.

THEO GRAY: Now, if you go the other direction, you end up with the alkali metals.

DAVID POGUE: The alkali metals are the first column. Each of them has full shells, plus one extra electron sitting in a new, outer shell.

They have familiar names like lithium, sodium and potassium. And they all want to get rid of that single, lonely electron, any way they can.

So those on that end of the table all have one extra. This column all has one too few. I shudder to ask what happens if you put those two alone in a room.

THEO GRAY: I happen to have a place where we might be able to do that.

DAVID POGUE: Am I invited?

THEO GRAY: Please, come to my lair.

DAVID POGUE: Turns out there's more to my friend Theo than mere love of table. He's also got a deep love of chemical reactions and a very remote location where he's free to indulge it.

Okay, they told me you were outstanding in your field, but this is ridiculous.

THEO GRAY: Yeah, well you know the secret to a good mad scientist's lair: no neighbors.

DAVID POGUE: Theo has an infectious attitude toward the most reactive elements…

Nice!

…which reminds me of a snake handler's affection for his most venomous pets.

Oh, ho, the humanity!

And one of his favorite temperamental friends? Sodium: symbol Na; 11 protons and 11 electrons arranged in shells as two, eight and one. Sodium is an alkali metal. Like all the elements in this group, it's desperate to get rid of that extra electron.

THEO GRAY: If you cut it quickly,…

DAVID POGUE: I should see some silvery…

THEO GRAY: …you should see a silvery surface inside.

DAVID POGUE: Indeed. Wow.

It slices like cheese, but it's actually a soft metal.

Theo's offered to put on one of his favorite sodium demonstrations. What happens when the pure element dumps its outer electron in a violent altercation with ordinary water?

He insists we wait until nightfall, when the reaction will be most spectacular.

Kids, do not try this at home!

The whole purpose of this contraption is just to dump it into the bucket of water?

THEO GRAY: Yeah. This is a, it's a sodium dumping machine.

DAVID POGUE: All right, let's give this a try. Here we go!

Nice! Oh!

What we're seeing is what happens when sodium's extra electron tears apart water molecules, releasing flammable hydrogen gas—the H in H2O—which explodes when it mixes with air.

The next day, Theo takes it up a notch. As if sodium plus water weren't violent enough, now he wants to combine the same deadly sodium with another lethal element: chlorine, one of the halogens.

The result, he claims, will be a tasty flavoring for a net full of popcorn.

Isn't chlorine deadly poison?

THEO GRAY: Absolutely.

I mean, chlorine, chlorine—they used it as a poison gas in World War I.

DAVID POGUE: It'll be perfectly safe when these two deadly ingredients combine?

THEO GRAY: I didn't say that. I said that after they're combined, the result is perfectly safe. The actual process of combining them is fraught with difficulties.

DAVID POGUE: Okay. And that's why we're dressed up like miners here.

First, a hunk of sodium in a dry metal bowl,then a jet of pure chlorine: surprisingly, no explosion.

Somehow, when these two bad boys of the periodic table come together, they calm down.

At the atomic level, sodium, an alkali metal, had an electron it didn't want, and chlorine, a halogen, wants desperately to grab an electron. Once the handoff was complete, both atoms wound up with full shells, making them stable and able to join together to form a crystal compound we can't live without: sodium chloride, table salt.

Now, I don't exactly see, like, a pile of salt anywhere.

THEO GRAY: No, the salt, most of it went up in the smoke. That is, it went in the popcorn.

DAVID POGUE: It tastes like salt, the good stuff, fresh.

THEO GRAY: Fresh salt.

DAVID POGUE: Only the freshest salt at Theo's farm.

Theo's backyard reactions have given me a crucial insight: how elements come together to form compounds is all about electrons.

Which brings me to one of the most notorious electron hounds on the table: oxygen; symbol O; eight protons, eight electrons; it wants eight electrons to complete its outer shell, but it has only six.

So it's always on the prowl for two more. And it's more determined than almost any other element on the table.

To get a first-hand look at oxygen's lust for electrons, I've traveled to the Energetic Materials Research and Testing Center at New Mexico Tech, where the business of violent reactions is booming.

TIM COLLISTER (Ordnance Technician): What he has here, in the rear, is four pounds of C-4.

DAVID POGUE: Four pounds?

It's a deadly serious business for researchers who study improvised explosive devices, I.E.D.s.

TIM COLLISTER: By adding the 5/16ths nuts, now we have something that's going to get propelled out of here at a few thousand feet per second.

DAVID POGUE: They have a wide variety of explosives on hand. On a typical day, they might blow up a suicide vest, a few pipe bombs and a briefcase bomb. Tim Collister's job is to train law enforcement and fire professionals how to deal with these dangerous weapons, but, today, I'm his only student.

We're going to set off one of the most powerful off-the-shelf explosives there is. In the trunk of this car, 300 pounds of ANFO, unassuming white pellets that contain enough oxygen, as well as nitrogen and hydrogen, to turn this car into a scrap heap. Basically, it's a fertilizer bomb.

This is not something I'm going to soon forget.

TIM COLLISTER: No you're not.

VOICE: Three, two, one.

DAVID POGUE: Hundreds of pounds of solid explosive, transformed, in a millionth of a second, into an infernal ball of superheated gas, expanding at more than 10 times the speed of sound: a devastating chemical reaction, yet many times smaller than the most notorious ANFO bomb ever detonated.

In 1995, over 4,000 pounds of ANFO, loaded into a rented truck, destroyed the Federal Building in Oklahoma City, killing and injuring hundreds of people. It's incredibly destructive stuff.

How does it work?

I don't know about you, but I am not seeing much car over there.

CHRISTA HOCKENSMITH (Senior Research Chemist): That's 'cause there's not much car left, David.

DAVID POGUE: To find out, I turn to the lab's chief research chemist, Christa Hockensmith.

CHRISTA HOCKENSMITH: The tires are still there.

DAVID POGUE: She's an expert in the chemistry of explosives.

Wow.

CHRISTA HOCKENSMITH: Whoo! Doesn't smell so good, does it?

DAVID POGUE: No. You know, we thought maybe the engine would become a projectile, to come hurtling out. The engine did not leave, but the entire car did: this whole front half. And the car used to be parked over there!

CHRISTA HOCKENSMITH: Ah! Look at this.

DAVID POGUE: With her help, I'm going to conduct a forensic investigation of the blast site.

CHRISTA HOCKENSMITH: Cadillac! But there's not much left.

DAVID POGUE: What kind of evidence can you derive from this? I mean the car is totally decimated.

CHRISTA HOCKENSMITH: Oh, no. We can do good work on finding out what caused this explosion with the magic swabs.

DAVID POGUE: We know what was in the bomb,…

I'm getting the hang of this now.

CHRISTA HOCKENSMITH: Yeah, you are. You're getting good.

DAVID POGUE: …but in an actual criminal investigation, this work is vital.

CHRISTA HOCKENSMITH: We're not picking up only filth. What we're picking up is what the bomb was made with.

DAVID POGUE: You think there's going to be traces, even on this fragment?

CHRISTA HOCKENSMITH: Not if you stick your fingers on it, no, but otherwise, yes. What you're going to find is, when we take these back to the lab, that we'll be able to tell what elements were present in the bomb.

DAVID POGUE: So much energy released so quickly—did oxygen have a role?

Still runs!

CHRISTA HOCKENSMITH: So, David, what did you think of that car bomb?

DAVID POGUE: Wicked cool.

CHRISTA HOCKENSMITH: Yes, it was.

DAVID POGUE: You have the luckiest job in the world.

CHRISTA HOCKENSMITH: You got the swab?

DAVID POGUE: Here's your swab.

CHRISTA HOCKENSMITH: Okay.

DAVID POGUE: Christa instructs me to dip the pad into purified water…

CHRISTA HOCKENSMITH: You can shake this up.

DAVID POGUE: Like that?

…to dissolve any chemical traces recovered from the debris.

Covered with paper pulp?

CHRISTA HOCKENSMITH: No, covered with nasty.

DAVID POGUE: All right. There you are. You go like this? Shall I suck it up?

CHRISTA HOCKENSMITH: Please. That's plenty.

DAVID POGUE: Okay.

CHRISTA HOCKENSMITH: Stick it right back into the ion chromatograph.

DAVID POGUE: Now you'll just feel a little pinch.

The ion chromatograph looks for positively or negatively charged molecules, called ions, in the residue, fragments of the original chemical explosive.

Well, there appears to be a spike, right here, at number three.

CHRISTA HOCKENSMITH: There sure does.

DAVID POGUE: What use is this analysis? Can you tell the State Department where the bomb came from?

CHRISTA HOCKENSMITH: I can.

DAVID POGUE: Really? And have you? Do they bring this?

CHRISTA HOCKENSMITH: I can't talk about that.

DAVID POGUE: You can just say yes or no. You can wink.

CHRISTA HOCKENSMITH: No, I can't.

DAVID POGUE: Different elements show up as spikes in different locations on the graph. Christa tells me this spike indicates that oxygen is at work here, contained in molecules called nitrates. Nitrates consist of three oxygen atoms bound to a central nitrogen atom. To set off the bomb, an initial spark of heat breaks those bonds. Once set free, oxygen rushes away from the nitrogen to combine with the elements it prefers: carbon, hydrogen and even other oxygen atoms, leaving the nitrogen to pair up with each other.

Every time atoms form a new bond, the reaction releases energy. And that's what powers the explosion.

But, in fact, we see similar oxygen reactions every day, like ordinary fire…

The heat of this flame is generated when carbon atoms in the wick bond with oxygen in the air.

…or rust, a very slow reaction when iron and oxygen combine.

Oxygen makes engines rev, rockets roar. And, in exactly the same way, oxygen reacts with the food we eat, releasing energy like countless tiny fires burning in our cells, keeping us alive.

All of these combustion reactions are essentially the same, the only difference is speed.

So how do you speed up a fire to create an explosion?

You regulate the amount of oxygen and how closely it's packed together with other elements.

As a final demonstration, Christa wants to show me how chemists have learned to control the speed of combustion. She has arranged the use of a high-speed camera to record several different types of explosives.

We take cover.

CHRISTA HOCKENSMITH: Bunker.

DAVID POGUE: Bunker.

The first demonstration will be ordinary gunpowder.

So, pure gunpowder is our first test here, right?

CHRISTA HOCKENSMITH: Yes. This is a smokeless powder. Whoa!

DAVID POGUE: Nicely done!

It was quick, but it wasn't blisteringly quick.

The gunpowder contains its own oxygen. But it's in a mixture of powdered chemicals held far away from the carbon it needs to bond with.

But when they finally find their partners, the new bonds they form release lots of energy. Gunpowder is a relatively slow explosive. That's why it's used in guns: it creates enough force to fire a projectile, but not enough to damage the barrel.

So, you're saying there must be explosives that don't take that long?

CHRISTA HOCKENSMITH: We're going to get faster and faster.

DAVID POGUE: Next is an emulsion gel explosive. Its main ingredient is ammonium nitrate, the same stuff that blew up the car. A lot more oxygen and a lot of nitrogen packed very closely together in a liquid.

VOICE: Three, two, one.

DAVID POGUE: Oh, jeez! Man, I could feel that puppy through here.

This is a high explosive. It generates a shockwave that moves faster than the speed of sound. In this explosive, oxygen, hydrogen and nitrogen are so close together they lose no time finding new partners and making new bonds that release energy.

The final demonstration is one pound of C-4, a military-grade high explosive, which burns fast enough to cut steel.

VOICE: Five, four, three, two, one.

CHRISTA HOCKENSMITH: Oh, jeez!

DAVID POGUE: There's nothing to see. It was there, and it was gone!

C-4 assembles oxygen, nitrogen, hydrogen and carbon in high concentration, close together, all on a big molecule, so the speed of reaction is blisteringly fast.

And that gives me an idea: maybe C-4 can help me exorcise a personal demon. What can I say? I have issues.

Quite frankly, Christa, I've been look forward to this one the most.

CHRISTA HOCKENSMITH: I am with you, a hundred percent.

DAVID POGUE: Clown.

CHRISTA HOCKENSMITH: Let's do it to the clown.

DAVID POGUE: Let's do it to the clown!

VOICE: Three, two, one.

DAVID POGUE: Okay! Well, the world is minus one clown, and I am out of therapy!

The oxygen that powers all those explosions makes up 21 percent of our atmosphere. It's the most abundant element in the earth's crust. It's also a big part of us, which makes me wonder: what other elements make life possible? What, for example, is in me? What's in a David?

Amazingly, I'm mostly made of just six elements, non-metals, mainly, from a small neighborhood on the periodic table: carbon, hydrogen, nitrogen, oxygen, phosphorus, sulfur, or, as some prefer to call them, CHNOPS. These are the elements that form the basis of all living things, from the most primitive bacteria to the largest creatures on earth.

It seems incredible that so much diversity could spring from such a tiny list.

But what I don't get is why these six? Why CHNOPS?

Professor?

CHRISTINE THOMAS (Brandeis University): Yeah?

DAVID POGUE: Sorry. I'm a little late for class.

Chemistry professor Christine Thomas, at Brandeis University, has agreed to help me understand what makes me tick.

I was told that you can help me understand C, H, N, O, P, S, CHNOPS, the elements of life.

Better than that, she's going to show me the actual elements, in the actual quantities that are in me, but I don't get how.

CHRISTINE THOMAS: I've prepared for you a CHNOPping list.

DAVID POGUE: A CHNOPping list?

You'll have to show me this. Where do you go to find the elements that make up a 185-pound man?

Isn't it a little weird that we're shopping for the elements of life at a hardware store?

CHRISTINE THOMAS: Does seem a little strange at first.

DAVID POGUE: But in fact, they're all here in these aisles, starting with C: carbon.

CHRISTINE THOMAS: All right, charcoal, right over here.

DAVID POGUE: Charcoal? Don't think of the human body being made of charcoal.

CHRISTINE THOMAS: Oh, it's made of carbon, and, you know, just trust me. You'll see.

DAVID POGUE: Hydrogen?

CHRISTINE THOMAS: Yep, that's next. We're going to get it right here, in water. In fact, we're going to get both hydrogen and oxygen all in one place.

So, next on the list is nitrogen.

DAVID POGUE: This is fertilizer.

CHRISTINE THOMAS: It is. And fertilizer, as it turns out, has a lot of nitrogen in it, just like you.

DAVID POGUE: I've been told I'm full of…never mind.

Next is phosphorous.

I'm not seeing phosphorus.

CHRISTINE THOMAS: There's, in fact, phosphorus in these matches. You're probably going to need…mmm…probably all of the matches that they have here. There you go! Oh, that ought to do.

DAVID POGUE: Hi, there. How are you? Just a couple things. We're having a couple people over for a grill.

A hundred sixty eight bucks? All the vital elements in this magnificent body, 168 bucks?

CHRISTINE THOMAS: Yep, that's it.

DAVID POGUE: So, you're telling me that our hardware store haul here actually is representative of the CHNOPS elements in all life and roughly in the right proportions?

Christine tells me we did pretty well, but we didn't quite nail it. We're still missing most of the phosphorous we need.

Luckily, she knows where to get some, thanks to a discovery by a 17th-century alchemist named Hennig Brandt. Brandt was looking for precious gold, and he thought he might find it in a bodily fluid that looks golden indeed.

All right. So we've got to get some, some urine, and we can, we can get phosphorus from it.

CHRISTINE THOMAS: Actually, you're going to provide a urine sample for us to study.

DAVID POGUE: Okay. Anything for science.

Turns out, the amount of phosphorous in my sample is microscopic. We're going to need a lot more, so back to the stable.

Centuries ago, Hennig Brandt had to collect gallons of urine for his experiment.

CHRISTINE THOMAS: Wow. I didn't think you had it in you; very impressive.

DAVID POGUE: Very funny. It was a lot of work, frankly.

The next step requires a concentrated sludge, which is urine minus most of the water.

Brandt's early process caused the phosphorous to rise as a vapor, which Christine directs safely into water, because phosphorous is dangerously reactive in the air.

While that's underway, it's time to get the lowdown on the stuff we bought, starting with carbon: 6 protons, 6 electrons in two shells.

Its pure forms include graphite, diamond, buckyballs, nanotubes and graphene.

You mean charcoal?

CHRISTINE THOMAS: Well, we bought charcoal to represent carbon, because it's made up of mostly carbon. Carbon, in its elemental form, looks like this graphite here, like you'd find on the inside of a pencil.

What charcoal is mostly is just left over, say, burnt wood. When wood burns, what's eventually left over looks an awful lot like this charcoal or this carbon.

DAVID POGUE: And the stuff in charcoal happens to be the foundation of all life on Earth, and for good reason.

CHRISTINE THOMAS: Carbon is the backbone of living things, because, since it can bond to itself, it can form these long chains of molecules.

DAVID POGUE: Long chains can form, because every carbon atom needs four electrons to fill its outer shell, which means it's eager to bond with up to four others, even carbon atoms. Virtually all long molecules in the body are built around carbon.

CHRISTINE THOMAS: Your body's about 18 percent carbon, which, for you, would be 33.3 pounds, which is equivalent to about two and a half bags of charcoal, here.

DAVID POGUE: All right, so next we have nitrogen.

CHRISTINE THOMAS: We do.

DAVID POGUE: For this you bought fertilizer.

CHRISTINE THOMAS: Right. So fertilizer is made up of a very large percentage of nitrogen, because plants actually use nitrogen as food.

DAVID POGUE: So how much actual nitrogen is in a guy like me?

CHRISTINE THOMAS: So your body's about three percent nitrogen, so in your case that's 5.6 pounds.

DAVID POGUE: Okay, hydrogen and oxygen. You have these tiles stacked side by side: hydrogen and oxygen, H2O, in water, a twofer.

CHRISTINE THOMAS: Hydrogen and oxygen can actually be separated from water using a little bit of electricity.

DAVID POGUE: Electric current breaks up the water molecule. The result is these tiny bubbles of hydrogen gas. Turns out, they're really quite volatile.

Ooh!

What the electric current accomplished, by separating water into hydrogen and oxygen, a simple flame put back together again.

CHRISTINE THOMAS: Now, notice what you see on here. It's a little cloudy, right?

DAVID POGUE: That little foggy spot on the test tube is brand new water, made just now by burning hydrogen and oxygen.

Hydrogen is the lightest atom in the universe, so even though there are more hydrogen atoms in me than any other kind, it adds up to only about 18 pounds.

Next: oxygen, also in water. Of course, I know how much fire likes pure oxygen.

CHRISTINE THOMAS: So, why don't you go ahead and light this twig here on fire.

When you see it starting to glow, go ahead and blow it out.

DAVID POGUE: Whoa-ho-ho! You have created fire!

Okay, so how much oxygen is in me?

CHRISTINE THOMAS: In a person's body, there's 65 percent oxygen; actually, in your body would equate to 120 pounds.

DAVID POGUE: That makes it sound like I'm a Macy's Thanksgiving balloon or something.

But as Christine has already demonstrated, it's not in me as a gas, it's in all that water.

And this brings us to P. I mean, of course, P as in phosphorous.

Hot phosphorus vapor, when cooled in water, turns into a solid.

CHRISTINE THOMAS: Yes. We've actually condensed it here as a nice chunky, white solid.

Phosphorus is actually involved in something really important called A.T.P., which is the molecule that all cells use for energy.

DAVID POGUE: Altogether, phosphorus makes up about one percent of my six-foot-two-inch body. Phosphorous was the first element isolated from a living creature, and it must have surprised Brandt.

Exposed to air, it glows, creating what he described as "cold fire." This chemical glow is what we mean today by "phosphorescence." And when burned in oxygen, it generates a spectacular pulsing display, called a phosphorous sun. No wonder it's used to provide energy in our bodies…and to think where it came from.

There's just one thing left on our CHNOPPING list: sulfur.

I don't get it. What does a tire have to do with sulfur?

CHRISTINE THOMAS: So, there's a very small fraction of sulfur in this tire, and as it turns out, there's the same amount of sulfur in this one tire as there is in a 185-pound David.

DAVID POGUE: Which is about how much?

CHRISTINE THOMAS: Which is about half a pound.

DAVID POGUE: Altogether just those six CHNOPS elements make up 97 percent of the weight of my body, but what about the other three percent?

And so, whatever is left over in those different beings must be what differentiates one from the next.

CHRISTINE THOMAS: Right. There's what's called the trace elements. And the person that would be better to talk to about those might be someone that's interested in maybe sports medicine or professional athletes.

DAVID POGUE: Let's see. Who could tell us about sports, athletes and elements? Who could tell us?

Hey, are you Lindsay?

LINDSAY BAKER: Yeah, I'm Lindsay.

DAVID POGUE: David.

LINDSAY BAKER: Nice to meet you, David. Welcome to the Gatorade Sports Science Institute.

DAVID POGUE: Gatorade Sports Science Institute; I know you guys are involved with elements in the body and athlete performance.

I actually am very concerned with these things, too. In fact, every morning, I take supplements. I use organic elements; I make my own. Calcium, very important. Sometimes I, sometimes I'll mix it up, get a little chalk. It might look like soap to you, but it's a fine source of potassium. Iron, zinc, magnesium…I like to think of this as an excellent source of sodium. And this is it, every morning.

You know, it doesn't taste fantastic, but, wow, is it good for me! Am I going about this the right way?

LINDSAY BAKER: Actually, David, there's a better way to get your elements, such as calcium, iron, magnesium in your daily food intake.

DAVID POGUE: But this is organic, free-range!

I'm curious to know how my body uses those trace elements, but, first, a battery of tests to determine what kind of shape I'm in.

Once I've been poked,…

LINDSAY BAKER: Go ahead and take all of your clothes off.

DAVID POGUE: Okay.

…weighed,…

LINDSAY BAKER: David, I said all your clothes.

DAVID POGUE: …measured and scanned,—and by the way, in the real world, this costs some serious money—she puts me on a treadmill to measure my oxygen use, which could be impaired if I have an iron deficiency.

LINDSAY BAKER: Okay. And start. We'll get to a nice comfy walking pace. Fifteen seconds, we're going to increase the speed.

Okay, David, what's your rating of perceived exertion?

Keep pushing.

Okay, David, how do you feel at this stage? Fifteen?

Where you at now?

He's at an 18. Okay, 10 more seconds, hard as you can. You can do it. Got any more left? Okay, okay. Go ahead and stretch. Go ahead and grab onto the railing. That's good, that's good.

DAVID POGUE: Next, a sweat test.

I haven't done this since I was a four-year-old girl.

SCOTT GADEKEN (Head, Physical Conditioning, IMG): I can tell.

All the way down. Good. Lock out at the top.

DAVID POGUE: This is how OSHA violations happen.

You know, if you play this video in opposite way, it will look like I'm really running.

Thank you, sir. It's been a pleasure. Go train somebody else.

SCOTT GADEKEN: We're just getting warmed up.

DAVID POGUE: Unfortunately, he wasn't joking.

Now they're ready to start the actual test.

These patches will collect my sweat, which, in turn, will tell Lindsay how much of the trace elements I'm losing from my body.

I feel like an old tire.

SCOTT GADEKEN: Here we go. Ready? Go!

DAVID POGUE: Shouldn't you have a mower attachment, at least?

SCOTT GADEKEN: Come on, drive it. Let's go.

Come on, stay lower. Use your butt, use your gluts.

Finish it, finish it!

All the way down, all the way up.

DAVID POGUE: Like that?

SCOTT GADEKEN: There you go. A little higher, a little higher, let's go. I'm going to start calling you names in a minute. Let's go.

DAVID POGUE: Oh, my god.

SCOTT GADEKEN: Keep going, keep going. That was two. Third-grade girls can get 10. Let's go, keep going.

Excellent job. Yeah. Great job.

DAVID POGUE: I have sweaty pads.

SCOTT GADEKEN: That's right.

DAVID POGUE: Come and get 'em!

So the purpose of all this was to measure what electrolytes and salts and stuff were leaking out of my sweat, right?

SCOTT GADEKEN: Yep.

DAVID POGUE: And why exactly do we care? Why do you care, in the athletes you train here?

SCOTT GADEKEN: What we want to prevent is athletes cramping, affecting their performance, not only in practices, but also in games.

DAVID POGUE: So you could be properly hydrated and still get cramps?

SCOTT GADEKEN: Correct.

DAVID POGUE: Well, thanks for the education, and thanks for the workout, Coach.

SCOTT GADEKEN: You got it. Any time, Dave.

DAVID POGUE: And now for the results.

My bone density test: normal; plenty of calcium in me.

LINDSAY BAKER: So, you have nice strong bones.

DAVID POGUE: So that means that my morning ritual of consuming calcium seems to be working.

LINDSAY BAKER: It is working. However, I would suggest dairy products to get your calcium instead of seashells.

DAVID POGUE: The treadmill: not so good.

LINDSAY BAKER: For your age and compared to other males, you're in about the 30th percentile.

DAVID POGUE: That's low.

LINDSAY BAKER: It's low. It's below average.

DAVID POGUE: This could mean one of two things: either I might have an iron deficiency, so my blood isn't carrying enough oxygen, or I'm really out of shape. And my blood test showed I'm not iron deficient, so…

Well, what about the other elements, what do they do?

Zinc?

LINDSAY BAKER: Zinc is important for energy metabolism.

DAVID POGUE: Potassium?

LINDSAY BAKER: Potassium is an important part of nervous system function.

DAVID POGUE: Magnesium?

LINDSAY BAKER: Energy metabolism.

DAVID POGUE: Okay.

And finally, what about sodium?

LINDSAY BAKER: So, sodium is important for nervous system function, that's why we did that test on you today.

DAVID POGUE: Luckily, my test results were normal. I may have been sweating a lot out on that field, but I sweat like a champ.

In total, the human body uses more than 25 elements in ways and quantities that are unique to us.

Not every living thing does it the same way. Take oxygen: we love the stuff, can't live without it, but it wasn't always this way. When life began, conditions were very different on Earth. To begin with, there was no oxygen in the air.

To learn what put the "o" in our at-mo-sphere, I've traveled to Yellowstone National Park.

David Ward has spent his professional life studying the earth's most ancient organisms.

So, Dave, you're a microbe expert, I hear.

DAVID WARD (Microbial Biologist):I am a microbial biologist. I study microorganisms, and I'm particularly interested in how they evolved.

DAVID POGUE: Well, when you say the earliest ones, how old are we talking about?

DAVID WARD: We're talking three, four billion years ago.

DAVID POGUE: Yellowstone sits atop the largest volcanic system in North America. That unusual geology creates hot, poisonous pools that Ward sees as a window into the past.

You installed a hot tub here.

The park permits Ward to collect samples from these protected environments.

So this is you, this is your office, huh?

DAVID WARD: Yeah. Now, you are not actually allowed to be inside the rocks there.

DAVID POGUE: D'oh!

DAVID WARD: You have to have special…a sampling permit. You stay here, and I'll go on across.

DAVID POGUE: Let me know if you need a bottle of water or something.

What is that gizmo you have there?

DAVID WARD: This is a thermistor, takes temperature.

DAVID POGUE: Oh, we call that a "thermometer?"

DAVID WARD: You know, scientists have to have fancy words for things.

DAVID POGUE: Scientists think that in order to get the energy they needed to live, some of the earliest forms of life required extremely hot water, mixed with elements like hydrogen, sulfur and iron. But, as the planet cooled, another ancient microorganism evolved and changed everything.

They are called cyanobacteria, but we know them as blue-green algae. They found a way to get their energy from light and water, releasing oxygen as a byproduct, just like modern plants do.

The evolution of cyanobacteria set the stage for all the plant and animal life that followed.

DAVID WARD: And in fact, you can see that clearly here. You can see this orange to brown transition.

DAVID POGUE: Yeah.

DAVID WARD: And, you know, this is one set of species, and then there's another, and then, finally, this third.

DAVID POGUE: Dave Ward offers to introduce me to one of my oldest living relatives, with the help of an ordinary drinking straw.

DAVID WARD: And we'll take a sample here. This is the real high-tech part.

I use my high-tech soda straw. Just take aim and push the straw in, and just immerse it into the liquid nitrogen.

DAVID POGUE: Wow, snap-frozen for freshness, huh?

DAVID WARD: Yep.

DAVID POGUE: The different colors are actually different species of microorganism.

Back at his lab, Ward prepares the sample.

DAVID WARD: There we go.

DAVID POGUE: Here, in the layers, we can see different species living together, separated by hundreds of millions of years of evolution. The thin greenish layer on the top is cyanobacteria, situated at the best spot to find light, water and carbon dioxide for growth.

And in the history of life, it's the cyanobacteria and us that truly came out on top.

DAVID WARD: Take a peek here, Dave.

DAVID POGUE: As they spread out of the volcanic pools and colonized the planet, these tiny organisms pumped out more and more oxygen.

For a few hundred million years, oxygen simply reacted with the metals in the earth's crust, and the planet slowly rusted.

But eventually the oxygen began to build up in the atmosphere. And those little bugs are still hard at work today.

DAVID WARD: These little critters that are making half of the oxygen that all of the things requiring oxygen breathe today.

So they're still at work making all of this oxygen.

DAVID POGUE: These microbes changed the face of an entire planet.

But where did the elements of life and all the other elements come from in the first place?

Let's start at the very beginning, with hydrogen: one proton and one electron. Around 90 percent of all the atoms in the universe are hydrogen, and they were all made by the Big Bang, more than 13 billion years ago.

But where did things go from there?

The answer is in the stars like our own sun, a seething cauldron of hot gas, constantly turning hydrogen atoms into element number two: helium.

It's a process called fusion.

And now, scientists at the National Ignition Facility in California are actually trying to recreate that solar process, here on Earth.

If they can make it practical, and that's a big if, they could unlock a new source of limitless, clean energy.

ED MOSES: So, the world is going to be using more energy.

DAVID POGUE: Ed Moses is a physicist who's leading the effort. And his raw material is hydrogen, the smallest and the oldest element in the universe.

ED MOSES: Around 30 seconds after the Big Bang, all that hydrogen appeared.

DAVID POGUE: From the Big Bang?

ED MOSES: From the Big Bang. It sort of has an infinite life. So we, when we, you know, drink a glass of water, are sampling the Big Bang.

DAVID POGUE: Fusion forces two hydrogen atoms to merge into a single helium atom: pound for pound it's the most energetic reaction in the cosmos.

And that's what his facility would like to reproduce.

ED MOSES: We crash them together. And what happens is we turn mass into energy, just like Einstein told us.

DAVID POGUE: To do this, Ed's team focuses 192 of the world's most powerful laser beams onto a BB-sized capsule containing hydrogen atoms.

This fuses them into helium atoms and releases a 100-million-degree pulse of energy. The goal is to create a sustained fusion reaction, but right now it lasts only a billionth of a second.

Stars create helium throughout their long lives, but in their old age they run low on hydrogen and begin to fuse helium, creating larger and larger elements.

ED MOSES: And you'll start walking up the periodic table, making more and more elements. First you made helium; then you'll make lithium and beryllium and boron.

And you can do this all the way up to iron.

DAVID POGUE: By the time it's fusing iron, a star is in its death throes. It begins to collapse, and if it's massive enough, that collapse leads to a powerful explosion called a supernova.

In that intense flash, the supernova creates elements heavier than iron, launching them all into the cosmos, creating the raw materials of planets and of life.

And now we're using those raw materials to shape our civilization, with elements like silicon—14 protons, 14 electrons—the second most abundant element in the earth's rocky crust; a member of the one of the smallest neighborhoods on the table: the semiconductors. When most people think of silicon, they think of computer chips and the information age, but its most familiar form is actually in this.

For more than 5,000 years, silicon glass has brought light and beauty to our lives.

Today, scientists are re-engineering this ancient material, atom by atom, here, at Corning, in upstate New York.

PETER BOCKO (Chief Technology Officer, Corning, Incorporated): You know, David, this place looks and sounds like a blacksmith shop, but, actually, it's a scientific laboratory.

DAVID POGUE: They're fiddling around with various combinations of elements…

PETER BOCKO: That's right. Yeah.

DAVID POGUE: …seeing what kind of glass comes out.

They tell me it all starts with ordinary sand, which is made of a combination of silicon and oxygen.

But sand is opaque, isn't it?

It turns out, it's much more glass-like than I thought.

PETER BOCKO: Under magnification, sand looks like little tiny glass jewels that are essentially transparent.

DAVID POGUE: So the light's coming from underneath these grains of sand and shining right through them?

PETER BOCKO: That's right, yep. And you know, it shows that it's transparent.

DAVID POGUE: That is so weird.

Melting sand and then allowing it to cool begins to turn it into glass.

Feels like thick, heavy vinyl.

Glass is surprisingly strong. It can withstand a lot of crushing force, but it's also very brittle.

Is there any way to get around that weakness?

PETER BOCKO: What the scientists do is they can tailor the glass, by adding other things other than the sand, to engineer the properties they want to into, into the glass.

DAVID POGUE: Should I worry that my gloves are on fire?

Changing the five-thousand-year-old recipe for glass has led to a new form they call Gorilla Glass, and you can probably guess why they named it that.

PETER BOCKO: Something that we call a drop test. With the glass…is in a frame, like we have a piece of Gorilla Glass in this.

DAVID POGUE: Okay.

PETER BOCKO: And the ball is dropped from a height of one meter.

DAVID POGUE: How thick is this piece of glass?

PETER BOCKO: This is 0.7 millimeters.

DAVID POGUE: Not even a millimeter?

PETER BOCKO: Not even a millimeter thick.

DAVID POGUE: We're going to drop four pounds on that?

PETER BOCKO: That's right.

David, this is our hail gun. It shoots a ball of ice at 60 to 70 miles an hour.

DAVID POGUE: Ready, aim, hail!

PETER BOCKO: So this is a sample of our special glass.

DAVID POGUE: This is plastic, dude. I can make a paper airplane out of this.

PETER BOCKO: Yeah, yeah.

DAVID POGUE: It didn't break.

Oh, my gosh! It's going to fold it in half. There's a lot of bend to it.

Ready, aim, fire!

The secret behind these weirdly durable forms of glass is engineering on the atomic scale.

Sweet!

Clearly it worked. The 70-mile-an-hour golf-ball sized hail did absolutely nothing to it.

The glassmakers have learned how to precisely place minute amounts of metal atoms like sodium, potassium and aluminum among the silicon atoms. The result is hard, yet flexible and scratch-resistant.

No, ho, ho…

But is it really glass?

You maintain that this is not, in fact, plastic…

PETER BOCKO: Mmm-hmm. Yep. Yep.

DAVID POGUE: …that this is actually glass?

PETER BOCKO: But yet, very strong, within reason. There is no such thing as an unbreakable glass.

It is a glass.

DAVID POGUE: Ooh!

PETER BOCKO: It is a glass.

DAVID POGUE: Ooh!

PETER BOCKO: So there are limits.

DAVID POGUE: These days, we need strong glass for lenses, fiber optics and screens of all sizes.

Hey, I'm on TV!

But silicon's work is not yet done, because underneath the glass, there's a lot more silicon in the guts of all those electronics.

Silicon is the standard bearer of the semiconductors, materials that change from free-flowing conductors to non-flowing insulators when we simply zap them with an electric current.

Switches made out of semiconductors made computers possible, but lately when it comes to high tech, there's a new family on the block: the rare earths—fifteen elements located near the bottom of the table.

And in my job as a technology writer, there's one rare earth that interests me more than any other, neodymium.

It's the key ingredient in the world's strongest magnets. They're critical to computers, cell phones, hybrid cars, wind turbines, even tiny ear buds. Without neodymium, we'd be sunk!

So that raises a question: if they're in everything, how come they're called "rare" earths?

The best place to find out is at the source. John Burba is the chief technology officer at Molycorp. He's overseeing a billion-dollar operation to bring this 50-year-old mine into the 21st century.

So how many rare earth mines like this are there in the United States?

JOHN BURBA (Chief Technology Officer, Molycorp, Inc.): One.

DAVID POGUE: This is it?

JOHN BURBA: This is it.

DAVID POGUE: One mine in the United States, and John tells me it's not even fully operational yet.

So, where do rare earth minerals come from in the world?

JOHN BURBA: The majority of it comes from China.

DAVID POGUE: What kind of majority?

JOHN BURBA: Like, 98 percent.

DAVID POGUE: Ninety-eight percent of these minerals come from China?

JOHN BURBA: Yes.

DAVID POGUE: Then he breaks the news that the Chinese government has been limiting the export of these strategically important elements.

Seems like the fate of the free world could be riding on these rocks. I'd better get some of my own while the getting is good.

JOHN BURBA: But look for stuff like this; we'll find out how good a geologist you are.

DAVID POGUE: This reddish stuff?

JOHN BURBA: Yeah.

DAVID POGUE: This is a hunk of, of what?

JOHN BURBA: Barite, barium sulfate…it's got some monazite in it. They are naturally occurring crystals that contain the elements.

DAVID POGUE: So, can I get a few more of these?

JOHN BURBA: Yeah, just look for stuff that, that's similar.

DAVID POGUE: You know what, John? I like these two a lot. I can't decide. It's an either "ore" situation.

So how can I find out which elements are in this hunk?

Molycorp's facility is still under construction, so, to find out what's in my rocks, he suggests I take them to the world's premier rare earth research lab, in Ames, Iowa. We'll be there soon.

I'm dying to know what I've got my hands on: a pinch of praseodymium, perhaps? A whole pound of holmium? A thimbleful of thulium? Or dare I hope, magnet-making neodymium?

If anyone can extract all the precious neodymium from my rocks, it's these guys.

LARRY JONES: David, I've been expecting you. Good to see you.

DAVID POGUE: David Pogue. How are you?

LARRY JONES: Yes, sir. Yes, sir. I see you brought the ore with you.

DAVID POGUE: I brought this all the way from California.

LARRY JONES: All the way? All right!

DAVID POGUE: I carried it by hand.

LARRY JONES: Uh-huh.

DAVID POGUE: Because you know it's rare earth…

LARRY JONES: It's rare earth.

DAVID POGUE: …ore, and I didn't want anything to happen. I didn't check it. I didn't put it in the overhead.

LARRY JONES: Yeah, okay.

DAVID POGUE: I think I got some beautiful samples.

LARRY JONES: Oh, yeah?

DAVID POGUE: There's this mine in California, the largest one in the United States.

LARRY JONES: Right.

DAVID POGUE: Look at the size of this one.

LARRY JONES: Oh, yeah.

DAVID POGUE: I think this one's my favorite.

LARRY JONES: Oh, yeah.

DAVID POGUE: I thought if we brought it here to Ames Lab, I thought you could do a little chemical analysis on it and tell me.

LARRY JONES: We certainly can.

Well, let's see.

DAVID POGUE: Yeah, watch out with that…

LARRY JONES: We'll take your favorite one and…

DAVID POGUE: Watch out with the hammer. What are you…?

LARRY JONES: See? Oh, yeah, there we go. That's a good piece right there. That's all we're going to need for the chemical analysis, so the rest of this we'll just…

DAVID POGUE: Yeah, but…

LARRY JONES: …throw it right here, in the trash.

DAVID POGUE: But, but that's, that's rare ear-, ah! California!

The truth is rare earths are not rare. They're just notoriously hard to separate. The problem is at an atomic level, the rare earth elements all look weirdly alike.

Moving from element to element, along a row of the periodic table, adds a proton to the nucleus and an electron to the outer shell, but in the rare earths, the new electron disappears into an unfilled inner shell. The result? Fifteen atoms that all have identical outer electron shells, making them virtually indistinguishable chemically.

But what about my rocks?

LARRY JONES: Okay, David, the ore that you brought us, the rocks that look like this, we analyzed those, and this is what we found: we found major components of cerium, lanthanum and praseodymium, but no neodymium.

DAVID POGUE: Apparently, my rocks are neo free.

But there was some good news. The ore I brought in contained a whopping 20 percent rare earth oxide.

Molycorp may soon be able to take a big bite out of China's near-monopoly.

Before I head out though, there's one more lab I'm determined to visit.

PAUL CANFIELD (Physicist, The Ames Laboratory): So, David, would you be interested in seeing a rare earth magnet?

DAVID POGUE: Paul is one of the lab's top magnet guys.

PAUL CANFIELD: This is a rare earth magnet. This is actually neodymium, iron and boron. This is about 150 grams of the world's highest purity neodymium.

DAVID POGUE: Neodymium magnets are a bit of a misnomer. They're really iron magnets, with a pinch of neodymium added like a powerful spice to make them stronger, plus a few boron atoms to help hold everything in place.

You grow these? You don't dig these out of the ore, somehow?

PAUL CANFIELD: No, no, no. These don't exist in nature. These are things that we have to combine and cook, in the same way that huevos rancheros doesn't exist in nature; it has to be put together.

DAVID POGUE: Paul's lab is like a dieter's kitchen, satisfying a hunger for powerful magnetic crystals, while reducing the amount of neodymium needed in the recipe.

And he's just about to whip up a fresh batch.

The main ingredient is ordinary iron. Iron makes magnets.

PAUL CANFIELD: There you go!

DAVID POGUE: But adding neodymium makes magnets on steroids.

Here's how you make a magnet: first, all the solid ingredients are sealed into a quartz tube, to be melted together.

Scientist!

After some time in the furnace, tiny magnetic crystals have formed in the melted iron.

Two thousand degree…oh, my gosh! It's like threading a needle!

The next step is to separate the solids from the liquid. One, two, three, dump it in, slam the lid.

They put the centrifuge on the floor for safety, in case anything goes wrong in the super-hot vial.

PAUL CANFIELD: We turn it off. That lets you open it up. And we can take it out.

We have single crystals of the neodymium iron boron, separated from the extra liquid, which the centrifuge separated with the ten to a hundred Gs.

DAVID POGUE: The result of all this cooking and spinning?

A powerful magnet that uses less neodymium, we hope.

It sounds like you're saying you're trying to use as little of the rare earth as possible.

PAUL CANFIELD: Absolutely.

DAVID POGUE: Why? 'Cause I thought that rare earths really aren't that rare.

PAUL CANFIELD: The rare earths are not rare, but they're hard to separate. And that's part of the expense.

DAVID POGUE: Even with Paul's help, it looks like rare earths are going to remain in short supply, at least for now.

Partly because scientists continue to find surprising new ways to use these strange metals.

Like marine biologist and conservationist Patrick Rice. If he has anything to say about it, rare earths may be coming soon to a fish hook near you.

Ah, is this your little kiddie pool where you bring the children to swim?

PATRICK RICE (Marine Biologist): This is our little tank here, where we have a couple little bonnet head sharks and a little nurse shark, in here.

DAVID POGUE: Rice was searching for the next great shark repellent, when he made an accidental discovery that looks like it'll be good news for both man and fish.

PATRICK RICE: We had sharks in a tank like this, and a pump broke on one of our tanks, and so, we were playing with these magnets, and we put the magnets down by the tank to go fix the pump, and when we put the magnet by the tank, the sharks took off.

DAVID POGUE: Somehow, the sharks inside the tank sensed the presence of magnets outside the tank, and when they did, they voted with their fins.

Patrick offers to demonstrate the weird repulsive effect. He hands me a case of super-strong magnets.

So this is, this is full of actual regular, old refrigerator…oh yeah, more than, more than refrigerator magnets.

PATRICK RICE: That's right, that's right.

DAVID POGUE: And you're saying that this will somehow repel the sharks?

Okay, here comes a little guy.

PATRICK RICE: That's a little nurse shark. It might work for him. Tell me when he gets over here.

DAVID POGUE: All right. Three, two, one.

Oh, my gosh. It's like you dropped that thing on his head.

PATRICK RICE: Yeah, you saw it, huh?

DAVID POGUE: Yeah, he's like, dun dun dun, wow! He, like, whipped out of there.

PATRICK RICE: Right. Right, right, exactly.

DAVID POGUE: The shark can't see the magnet, but it obviously feels the effect.

And it's not happy.

PATRICK RICE: One, two, three, now. Boom! You got him.

DAVID POGUE: Really?

PATRICK RICE: Yeah, you got him.

DAVID POGUE: That's crazy.

PATRICK RICE: Isn't it amazing?

DAVID POGUE: Patrick thought he could somehow use this effect to save sharks from being inadvertently caught by commercial fishermen, but there was, so to speak, a catch.

PATRICK RICE: We put the magnet right above the hook, on the line.

DAVID POGUE: Oh, okay.

PATRICK RICE: And what was happening was the hooks were swinging around and getting caught on the magnets.

DAVID POGUE: That would happen.

PATRICK RICE: So, it wasn't catching any sharks, but it wasn't catching anything else either.

DAVID POGUE: But he wasn't willing to give up. He decided he needed to find the weakest possible magnet that would still effect sharks.

The first step was to create a baseline for comparison, by exposing sharks to non-magnetic materials.

He offers to recreate his experiment.

You know, I don't have insurance for this.

PATRICK RICE: Be careful. It might be slippery.

DAVID POGUE: You're warning me about the slipperiness? Dude, there's three sharks in here!

PATRICK RICE: No, but they're nice.

DAVID POGUE: Okay, I just want to say, for the record, that I'm standing in a tank full of sharks.

PATRICK RICE: That's correct.

DAVID POGUE: This is like Jaws 7: The Kiddie Pool.

Step one: capture a shark.

Dude, you just caught a shark with your bare hands!

Then, flip the shark upside down, which induces a trance state called "tonic immobility." Once the shark is calm, we test its reaction to a piece of ordinary, non-magnetic lead.

Would you like me to just conk her on the head with this?

PATRICK RICE: Cover up her eyes.

DAVID POGUE: So it's not a visual thing.

Using a shield, to make sure that the shark can't see the metal, I bring it close.

PATRICK RICE: No reaction.

DAVID POGUE: None at all, as expected.

Next: a non-magnetic piece of samarium, a rare earth element. The expectation was that, because it's non-magnetic, there would be no reaction.

Oh, man.

PATRICK RICE: She didn't like that at all.

DAVID POGUE: This is like kryptonite for sharks.

PATRICK RICE: Yes, it is.

DAVID POGUE: Wow, that's amazing. It just woke her up and drove her crazy.

PATRICK RICE: Yep.

DAVID POGUE: So the idea is you could make what out of this stuff?

PATRICK RICE: Well, the idea is that it's not magnetic, so we could potentially incorporate it into a fishing hook. And then you got something that repels sharks but doesn't have the magnetic properties, so it won't tangle the gear and stuff like that.

DAVID POGUE: The discovery that non-magnetic rare earths have a repellent effect on sharks was a complete fluke.

And it works with other rare earth metals as well. But why? What do sharks have against these particular elements?

PATRICK RICE: We believe it's creating a little electric shock.

DAVID POGUE: A little electric shock?

PATRICK RICE: Yeah, yeah.

DAVID POGUE: A shark shock?

PATRICK RICE: A shark shocker.

DAVID POGUE: Patrick demonstrates, using a beaker of seawater, a piece of samarium, a voltmeter and an actual shark fin.

(Singing) Bum bum, bum bum, bum bum, bum bum…

When he submerges the samarium and the shark fin in the seawater, an electric current flows.

Whoa! Oh, my god.

PATRICK RICE: That's almost a D-size battery.

DAVID POGUE: You're kid-…did we just make, in effect, a battery?

PATRICK RICE: Correct.

DAVID POGUE: As a group, the rare earths give up their outer electrons very easily. In the salt water, samarium atoms break free of the metal disk and give up one or more of their outer electrons. The atoms become positively charged and are attracted to the shark fin, which, like many biological materials, has a slight negative charge. The movement of the charged atoms creates an electric current.

Wow, that's some real juice flowing in there, just like in a battery.

It is like a battery, isn't it? It's a complete closed circuit, and the voltmeter's measuring that. That's pretty amazing.

PATRICK RICE: Yeah.

DAVID POGUE: But is the effect actually strong enough to put a shark off its meal?

PATRICK RICE: So we've just done our little test.

DAVID POGUE: There's one final experiment we can run to find out.

PATRICK RICE: What we're going to do now…

DAVID POGUE: Thank you.

PATRICK RICE: You're welcome.

DAVID POGUE: That was just for the blooper reel. We like to get some material…

As I was saying, there's one final experiment we can run to find out.

PATRICK RICE: What we're going to do here is a little experiment we've never done before.

DAVID POGUE: You haven't done this before?

PATRICK RICE: We haven't done this before.

DAVID POGUE: You waited until there was a national TV camera rolling?

There's a nine-foot lemon shark in this lagoon, and it's lunchtime.

Now for the test: we're going to suspend two identical pieces of tuna. One will hang below a piece of lead,—that's our control—the other under a piece of samarium.

PATRICK RICE: You go ahead and put it out there.

DAVID POGUE: Really?

PATRICK RICE: Yep.

DAVID POGUE: Lower her down.

If the test is successful, the shark should avoid the samarium-tainted meal, but not the food near the lead.

PATRICK RICE: Here she comes.

DAVID POGUE: Oh, she didn't like it at all. She was aiming right at it and she was like, "Uhhhh!"

PATRICK RICE: That was an excellent response. Notice the other fish; it doesn't have any effect on them.

DAVID POGUE: Okay, wait a minute. Now she's going for the lead.

PATRICK RICE: So there's the control.

DAVID POGUE: And she loves the lead one!

PATRICK RICE: No problem on the control, so, that's awesome.

DAVID POGUE: Since making this remarkable discovery, Patrick has experimented with designs for shark-repelling fishing hooks, and he's seen some promising results.

PATRICK RICE: The last experiment we did, we put out 46,000 hooks, and we reduced shark by-catch by 27 percent.

DAVID POGUE: Get your fresh chum, here!

Shark zapping is just the latest entry in the growing list of curious rare earth abilities.

But perhaps the real shocker is that these 15 elements were so long misunderstood, their identities masked by their identical outer electron shells.

But those aren't the only atoms hiding from view. Scientists now know that most elements come in more than one version. The different versions are called isotopes.

Consider carbon, the backbone of life. It has three natural isotopes, or versions. Each has six protons and six electrons. That's what makes them all carbon. The difference between them is the number of neutrons in the nucleus.

Neutrons are electrically neutral particles that act as glue to hold atoms together. What we think of as normal carbon is called carbon-12: six protons plus six neutrons. But about one percent of carbon atoms have an extra neutron, giving them seven. They're called carbon-13.

And about one in a million have eight neutrons. That's carbon-14.

And that rare version of carbon has proven to be a crucial tool for unlocking the past.

Several times a year, scientist Scott Stine travels to the shores of Mono Lake, near Yosemite National Park.

So this, then, is Mono Lake.

SCOTT STINE (Paleoclimatologist): Mono Lake, yeah. Right here, at the foot of the Sierra Nevada.

DAVID POGUE: He's studying the long history of droughts in California, trying to determine how frequently they occur and how long they last.

Over the millennia, the water level has risen and fallen, as the area has cycled between wet periods and dry times.

So that sandy area should be the level?

SCOTT STINE: During times when the climate was dry, Mono Lake dropped down, exposed the shore lands, and allowed trees and shrubs to grow. When the dry periods ended and the water level rose, the trees drowned, marking the end of the droughts.

Since then, the remains of those trees have been well preserved by the arid climate.

These droughts were long and persistent.

DAVID POGUE: To determine how long ago these droughts occurred, Scott is using carbon-14 to date the trees.

Unlike the other natural isotopes of carbon, carbon-14 is unstable. Over time, its atoms begin to deteriorate. One of its neutrons turns into a proton and spits out an electron. Now, with seven protons instead of six, it's turned into nitrogen.

That process is called radioactive decay. And scientists know exactly how long it will take for half of any amount of carbon-14 to decay away. Scientists call that time its "half-life."

Living things constantly replenish the carbon in their bodies, animals from food, plants from the atmosphere, but after death, that process stops.

The amount of carbon-12 stays the same, but the carbon-14 decays away, at a constant rate, making carbon-14 a ticking atomic clock.

To know how long ago this ancient tree died, we just need to count the carbon atoms in a small sample—piece of cake, if you're this guy.

Now, these are fragments of the tree stumps at Mono Lake, and I understand that you are the master of carbon-dating.

Physicist Tom Brown works in the carbon-dating program at Lawrence Livermore National Laboratory. In fact, if I'm not mistaken, carbon dating actually preexisted before Internet dating.

TOM BROWN (Research Physicist, Lawrence Livermore National Laboratory): Very much.

DAVID POGUE: Carbon-14 can be used to date samples up to 40,000 years old. It's been used to find the ages of many Egyptian mummies and other ancient artifacts.

So how does wood fare with carbon-dating?

TOM BROWN: Intact wood is very good material to date. It retains the carbon from when that material died, and we're able to extract and purify it and get a really good material for dating.

DAVID POGUE: Tom needs only a small amount of wood, even this tiny sample is overkill.

A lab technician cleans it and reduces it to a fine powder.

Oh, man, this huge thing, this is your Carbon-Dater-Matic 3,000?

The actual counting of the atoms takes place here, in the carbon-dating accelerator.

I see you bought the camping version.

TOM BROWN: So we have our one milligram of carbon from the wood chip sample, basically, in that hole.

DAVID POGUE: In that tiny little hole?

TOM BROWN: That's where the one milligram of carbon is, from that sample.

DAVID POGUE: Not a lot of wood chips.

TOM BROWN: We put about 64 of these holders in one of these wheels.

DAVID POGUE: The accelerator applies a powerful electric charge to the atoms—basically lightning—giving them the speed and energy they need to hit a detector with enough force to be counted.

TOM BROWN: The ratio of the carbon-14 ions to the amount of carbon-12 in the sample tells us how old the sample is.

DAVID POGUE: The fewer the carbon-14s, the older it is?

TOM BROWN: Yes.

DAVID POGUE: With his accelerator, Tom calculates that our tree died about 150 years ago. That must have been when California's last drought ended, a key piece of information for understanding the region's climate cycles.

Carbon-14 has helped open up deep insights into the past, but it's just one of hundreds of radioactive isotopes, that is, elements that decay.

In fact, at the bottom of the periodic table, beginning with number 84, polonium, all of the elements and their isotopes are radioactive, including the element that stands for both the promise and the peril of radioactivity: uranium: 92 protons, 92 electrons and 146 neutrons.

Before the nuclear age, uranium was thought to be the end of the periodic table, but in the last 70 years, scientists have left nature behind and created 26 new elements.

The age of manmade atoms began in the first half of the 20th century, when researchers began bombarding elements with neutrons. Sometimes the neutron is simply absorbed, creating a new isotope, but sometimes the nucleus can't take the punishment. It becomes unstable and splits into two smaller atoms, in a powerful reaction, called fission, that releases large amounts of energy.

To learn more, I've come to the Nuclear Museum, in Albuquerque, New Mexico,…

MATTHEW DENNIS (Nuclear Engineer, American Nuclear Society, Trinity Section): Yeah, this is a mad science project.

DAVID POGUE: …where atomic scientist Matt Dennis has offered to demonstrate how a nuclear reactor works.

D'oh! You guys make a lot of jokes about "Gone fission?"

MATT DENNIS: I actually have an atomic shirt that says something to that effect, so, yes, yes.

DAVID POGUE: I knew that! I knew that!

Okay, now, to the naked eye, this looks exactly like a nuclear reactor.

MATT DENNIS: The similarities are the mousetraps are uranium atoms and the white ping pong balls are neutrons, which…you use one to start a chain reaction.

DAVID POGUE: In a reactor, one neutron splits a uranium atom, which releases energy and two or three more neutrons, which, in turn, split more atoms, releasing more neutrons and so on, causing a chain reaction.

MATT DENNIS: So you get more and more neutrons, and thus, the chain reaction keeps going.

DAVID POGUE: All right, ladies and jelly spoons, here goes the orange ping pong ball. This evening's role, you'll be portraying the neutron. All right, I just drop it in here? Any old place?

MATT DENNIS: Just drop it in right there. We'll start the chain reaction.

DAVID POGUE: Incoming neutron!

I'm sorry, Matt. The camera wasn't rolling. Can you set that up again?

From a single neutron, an escalating response. Our mousetrap reactor doesn't have many atoms, so the reaction dies quickly, but pack enough fissionable uranium atoms closely enough together and the whole thing can get out of hand pretty fast.

And sometimes, that's the point.

This museum has the world's largest public collection of artifacts that chronicle the dark side of nuclear energy.

JAMES WALTHER (Director, National Museum of Nuclear Science & History): And so, that's a Trident Z-3, up there.

DAVID POGUE: That's huge. You guys are just surrounded by bombs. I feel like a kid in a death store.

In 1945, the U.S. developed two atomic weapons. Both were used against Japan.

The first was fueled by an isotope called uranium-235. That bomb was called Little Boy.

JAMES WALTHER: This is the Little Boy bomb. This is the…

DAVID POGUE: This is it? I guess I shouldn't bump it then, huh?

JAMES WALTHER: Well, it's a current—concurrent copy.

This is just like it. Inside this big case was a gun barrel and high explosives on the ends, to push the two pieces of enriched uranium together at supersonic speed.

DAVID POGUE: The military made only one uranium bomb, because separating rare U-235 from the more common U-238, which doesn't work in fission reactions, is a very difficult process.

So for the second bomb, called Fat Man, they used an entirely different element, plutonium: 94 protons, 94 electrons and 150 neutrons.

Plutonium was the first manmade element. It was first created as an accidental byproduct in the first nuclear reactors.

But no one knew it, until plutonium was identified, in 1940, by chemist Glenn Seaborg, when he bombarded uranium atoms with protons and neutrons, until some of them stuck.

Over his long career, Se