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NOVA scienceNOW: June 30, 2009

PBS Airdate: June 30, 2009
Go to the companion Web site

NEIL DeGRASSE TYSON (Astrophysicist/American Museum of Natural History): Hi, I'm Neil DeGRASSE Tyson, your host for NOVA scienceNOW. Welcome to a brand new season.

On this episode, I'm blindfolded and taken to a secret location.

Where am I?

Why? Well, because of what they produce here: diamonds.

BRYANT LINARES (Apollo Diamond, Inc.): The diamonds are 100 percent real diamond. They're chemically, physically and optically identical to mined diamonds, with one exception: we grow them.

NEIL DeGRASSE TYSON: Yes, they're growing diamonds, and not just for bling. Diamonds have unique properties.

It's cutting through the ice like a knife through butter.

Some say they could someday replace silicon chips.

STEPHEN STEINER (Massachusetts Institute of Technology): Silicon is so 20th century. It's time to move on.

NEIL DeGRASSE TYSON: But can these manmade diamonds fool an expert?

ARA ARSLANIAN (Cora International): If I have to guess, I would guess this one.

NEIL DeGRASSE TYSON: Also, we'll profile a game-playing, TV-watching computer science professor who could pass for one of his own students, many of whom he calls "dude."

LUIS VON AHN (Carnegie Mellon University): ...like, "Dude." And they're like, "Dude."

NEIL DeGRASSE TYSON: This dude is so creative, not only did he invent a key internet program millions of us use every day, but he figured out how to turn this mindless task into valuable work.

LUIS VON AHN: What can you do when you can get 100 million people working on the same thing? And I think we can do amazing things.

NEIL DeGRASSE TYSON: And within weeks of the 9/11 terrorist attack, weapons- grade anthrax had been dispersed though the mail.

ALAN ZELICOFF (Bioterrorism Expert): The first thought that most of us had was that this was likely a state-sponsored effort to cause harm in an already chaotic situation.

NEIL DeGRASSE TYSON: The F.B.I. led one of the most extensive and expensive criminal investigations ever, and it was the new science of microbial forensics that cracked the case. We'll show you how, and more, on this episode of NOVA scienceNOW.

Funding for NOVA scienceNOW is provided by The National Science Foundation, where discoveries begin. And...

Discover new knowledge; biomedical research and science education; Howard Hughes Medical Institute: HHMI.

And the Alfred P. Sloan Foundation to enhance public understanding of science and technology and to portray the lives of men and women engaged in scientific and technological pursuit.

And the George D. Smith Fund.

And by PBS viewers like you. Thank you.

DIAMOND FACTORY

NEIL DeGRASSE TYSON (As Treasure-Hunter Indiana Jones): Treasure hunters are known for taking risks, especially if they're after something as valuable as a giant diamond.

These days, big diamonds are in demand, and not just for jewelry. Some think they hold a key to a new age of electronics. ...problem is the right kinds of diamonds are extremely rare in nature and hard to find.

(As Scientist Indiana Jones): Dr. Tyson, we have an answer.

(As Treasure Hunter Indiana Jones): Some scientists have a new recipe for diamonds, made, not in the earth, but in the lab.

Recently, I got to visit a secret place. I can't tell you where it is, because, well, I don't really know where it is. I could only get there if I agreed to be blindfolded.

BRUCE LIKELY: It will be a little while driving, so make yourself comfortable.

NEIL DeGRASSE TYSON: In fact, the location is so secret, our entire film crew had to be blindfolded.

When I finally got to peek, it didn't look all that unusual.

Where am I? Oh, sorry!

But don't let appearances fool you.

ROBERT LINARES (Apollo Diamond, Inc.): You're at the U.S. diamond factory.

NEIL DeGRASSE TYSON: A diamond factory?

Or maybe a better term would be a diamond "farm," because, as I discovered, what they're doing in the back rooms of this ordinary office building is actually growing diamonds.

BRYANT LINARES: The diamonds we grow are 100 percent real diamond. They are chemically, physically and optically identical to mined diamonds, with one exception: we grow them.

NEIL DeGRASSE TYSON: And some of the diamonds they grow here are beautiful.

So basically, you're making diamonds in machines like this?

But Robert Linares didn't start this company simply to make bling. He wants to make diamonds that will revolutionize technology.

ROBERT LINARES: Diamond is going to have a huge worldwide impact for the next 50 years.

BRYANT LINARES: It's going to be in our cell phones. It's going to be in our electric cars and in our power grid. It will be everywhere.

NEIL DeGRASSE TYSON: The company hopes to realize the potential that scientists have seen in diamond for years. Because it's not just pretty, it's one of the most impressive materials in the universe.

PATRICK DOERING (Apollo Diamond, Inc.): Diamond has an amazing toolkit of properties.

JAMES E. BUTLER (Naval Research Laboratory): You can boil it in any acid or any base and it doesn't destroy diamond.

PATRICK DOERING: The highest velocity of sound is in diamond. If you could speak to somebody through diamond, the sound would get there much faster than it would through air.

NEIL DeGRASSE TYSON: And it's not just sound that travels quickly through a diamond. Heat moves faster through a diamond than any other known substance.

Jim Butler at the Naval Research Lab demonstrated this to me with a simple experiment...

JIM BUTLER: Do you have a credit card?

NEIL DeGRASSE TYSON: ...and a block of ice.

I only just met you, so how about my triple-A card?

JIM BUTLER: That's fine with me.

Press against the block and count the number of seconds until your fingers get cold.

NEIL DeGRASSE TYSON: This is going to take awhile.

JIM BUTLER: This is going to take awhile, so it's not going to happen. And did it make any dent in the ice?

NEIL DeGRASSE TYSON: Okay, I don't see any. Nothing, there's nothing there.

JIM BUTLER: So, how about a piece of copper? So hold it by the edge.

NEIL DeGRASSE TYSON: This'd be like holding a penny.

JIM BUTLER: Yeah, holding a penny, but this is just a nice, pure piece of copper.

NEIL DeGRASSE TYSON: About a half inch from the edge.

JIM BUTLER: Okay, now count the number of seconds.

NEIL DeGRASSE TYSON: Oh, right there!

JIM BUTLER: So, how many seconds?

NEIL DeGRASSE TYSON: That was three seconds.

JIM BUTLER: Three to four seconds. And what did you do to the ice cube?

NEIL DeGRASSE TYSON: It's still cold. I cut the ice.

This small piece of copper sliced right through the ice, because, unlike the plastic card, copper is an excellent conductor of heat. So it drew the heat right out of my fingertips, melting the ice and leaving my fingers cold. Impressive, huh?

But then, Jim offered me a big chunk of diamond.

JIM BUTLER: Hold it just by the tip. Now, touch the ice and count the seconds.

NEIL DeGRASSE TYSON: Instant. It's cutting through the ice like a knife through butter.

JIM BUTLER: Yes.

NEIL DeGRASSE TYSON: It turns out diamond conducts heat five times faster than copper.

All this is possible because of diamond's unusual crystal structure. Pure diamond is made of all carbon atoms, but the carbon atoms have to be arranged in a unique way to give it the amazing properties of diamond.

If you arrange the carbon atoms in another way, you get this: graphite, one of the softest materials around.

STEPHEN STEINER: Well, obviously, these are two very different materials. Graphite is black, it's opaque; when we rub it against paper, it comes apart. Whereas diamond is transparent; it's hard, one of the hardest substances known to mankind.

PATRICK DOERING: Diamond has the highest atomic density of any material. So there's more atoms per cubic centimeter than any other material.

NEIL DeGRASSE TYSON: But diamond isn't just hard, it has impressive electrical properties, as well.

STEPHEN STEINER: A centimeter-thick plate of diamond can withstand 10 million volts of electricity.

NEIL DeGRASSE TYSON: Electrical engineers would love to exploit these unique properties, but they've been frustrated by the ones that come out of the ground, because they're all slightly different.

JIM BUTLER: The reason we cannot use diamonds out of the ground for a lot of technological applications is because no two are alike. They're like snowflakes. Have you ever seen two snowflakes that are alike? We've got billions of diamonds that we've mined out of the ground but trying to find two that have exactly the same properties is actually very difficult.

NEIL DeGRASSE TYSON: It all comes down to how natural diamonds form. Most natural diamonds formed billions of years ago, deep beneath Earth's crust, under extreme pressures and temperatures. Volcanic activity transported them to the surface, where we find them today.

PATRICK DOERING: So the earth is not a really well-controlled crystal growth furnace. So what happens is you're left with whatever the earth gives you. You have to then scratch your head and say, "What can I do with it?"

NEIL DeGRASSE TYSON: Decades ago, engineers figured out how to make diamonds in giant, hot vises. But the process is impractical for making large stones, and it's difficult to produce a crystal that's pure carbon without defects.

But what if you can manufacture diamonds and guarantee purity and consistency?

ROBERT LINARES: Neil, you have to put your glasses on.

NEIL DeGRASSE TYSON: The folks at Apollo Diamond say they can do it.

They're one of just a few companies making diamonds using technology known as "chemical vapor deposition," or C.V.D.

PATRICK DOERING: So, to grow a diamond, you have to start with a piece of diamond. So you start with a very thin plate of diamond. It's as thick as a human hair.

NEIL DeGRASSE TYSON: Here's how it works: they start with thin slices of pure diamond called "seeds." The seeds are then placed inside a vacuum chamber; a cocktail of gasses is pumped in. Apollo's exact recipe is top-secret, but it, of course, includes gasses that contain carbon—such as methane—which are heated to extreme temperatures, so they become what's called a "plasma."

So what temperature is that plasma?

PATRICK DOERING: That plasma—if you could measure—the temperature's probably 3,000 or 4,000 degrees Celsius. It's about the same temperature of the gas that you'd find at the edge of the sun.

NEIL DeGRASSE TYSON: The extreme heat breaks apart the gas molecules, and then, through a complex chain of reactions, carbon atoms take their place on the crystal below, following the pattern established by the diamond seed.

Over the course of a week or more, diamonds grow bigger and bigger. When they emerge from the grower, they don't look much like diamonds, until they're cut and polished. And then...

The diamonds baked up here look great to me, but what would an expert think? To find out, I took a sample to the famous diamond district in New York City, where I met Ara Arslanian, who buys and cuts some of the most impressive stones in the world.

ARA ARSLANIAN: Fifty carat, they will charge you four million.

NEIL DeGRASSE TYSON: Aah! Not 10,000, not 100,000?

ARA ARSLANIAN: No, no, no. This is real, the real McCoy.

NEIL DeGRASSE TYSON: This is the real thing?

ARA ARSLANIAN: This is the real thing.

NEIL DeGRASSE TYSON: So, you know why I'm here.

So, even though small stones aren't usually his thing, Ara agreed to participate in our little experiment.

Point-two-nine and point-three carat.

I showed Ara three small cut gemstones. One was grown in Apollo's lab, the two others came from diamond mines.

ARA ARSLANIAN: ...so tiny. I'm not used to those.

NEIL DeGRASSE TYSON: As I told you, at least one of these is manmade.

ARA ARSLANIAN: Let me put this thing on my telescope. Here we go.

NEIL DeGRASSE TYSON: I see them sparkle from here...

ARA ARSLANIAN: Yeah.

NEIL DeGRASSE TYSON: ...as all good diamonds should do.

ARA ARSLANIAN: They pretty much look the same. So, normally, I'm a rough guy; I do the rough diamonds. If I have to guess—well it's a wild guess—I would guess this one.

NEIL DeGRASSE TYSON: That's the .3 carat.

The one that is manmade is this one.

ARA ARSLANIAN: But I know what I'm seeing, I'm seeing here. I couldn't distinguish which one is manmade and the natural.

NEIL DeGRASSE TYSON: With the customary jeweler's loupe, Ara couldn't detect any difference in the manmade diamond.

ARA ARSLANIAN: Yeah, it's amazing what they can do. It's like a toupee. It's the feeling which got...you can...which one you prefer, the toupee or your real hair?

NEIL DeGRASSE TYSON: The real hair.

ARA ARSLANIAN: Even if the toupee looks great.

NEIL DeGRASSE TYSON: More advanced equipment can reveal subtle differences, and Apollo isn't trying to trick anyone. In fact, their manmade gemstones are marked with a microscopic brand, so the people who buy them know just what they're getting.

But for scientists, what's most exciting about growing diamonds is not how you can make them just like natural stones but how you can make them different.

Because with chemical vapor deposition, or C.V.D., diamonds can be grown into shapes and sizes nature could never produce.

And you can tinker with the recipe.

JIM BUTLER: In a C.V.D. diamond we can actually control how we grow the diamonds. We can engineer the material to have the property match the application that we need.

NEIL DeGRASSE TYSON: For example, add a little bit of the element boron to the carbon gas mixture, and you get a blue diamond. That's where the famous Hope Diamond gets its distinctive color, but boron does more.

PATRICK DOERING: So when you put the boron in it, it not only makes the diamond blue, it also changes its electrical properties. So a diamond with no boron, perfectly pure

diamond, basically, you can't get any electricity to flow through it. When you put boron in, you can now get electricity to flow through the diamond. And this is an essential component, if you want to make an electronic device.

NEIL DeGRASSE TYSON: Today, most electronic devices, from computer chips to televisions, are built from silicon. But silicon has its limits.

STEPHEN STEINER: Silicon is so 20th century. It's time to move on. Silicon has some fundamental drawbacks: it fails when it gets hot. Somewhere around the boiling point of water, it starts to break down. It's not able to process information anymore.

Well, it turns out that there are a number of features of diamond which blow silicon out of the water.

NEIL DeGRASSE TYSON: So, take an electric train. Today, these modern machines carry tons of silicon transistors to manage the high-voltage electricity coming into the train. But what if you could make those transistors out of diamond instead?

STEPHEN STEINER: Diamond can come to the rescue. Diamond has the ability to switch much higher frequencies, much higher voltages.

JIM BUTLER: Then all of that electronics could be simplified, the weight could be removed. You could envision that your train, instead of having one to two tons of electronics per railcar, might have only fifty pounds of electronics per railcar.

NEIL DeGRASSE TYSON: And a lighter train is more energy efficient.

The field of diamond electronics is in its infancy, and a lot more work needs to be done before diamond starts replacing silicon, but the potential is there, and the diamond growers have big dreams: diamond switches that could improve our aging electrical grid, diamond windows for spacecraft, and who knows what else?

STEPHEN STEINER: Mother Nature was the only manufacturer of diamond for a really long time. And that's what's so exciting about a material like diamond...is because it's kind of been kept in a little treasure box for a long time, and now, we've just begun to open that treasure box, and all of the possibilities which come with it are beginning to emerge, as well.

On Screen Text: So what is Apollo's secret ingredient? They're still not saying. But diamond-making scientists at the University of Nuevo Leon, Mexico use tequila. We're not kidding. They created diamonds using a similar process and their own "secret ingredient."

ANTHRAX INVESTIGATION

NEIL DeGRASSE TYSON: When a murder is committed, one of the key ways to link the culprit with the crime is by tracing the murder weapon. For instance, every gun leaves a unique signature on the bullets it fires. Match the lethal bullet to the gun, you might find your murderer.

But what if the murder weapon isn't a bullet, but a tiny microbe, invisible to the naked eye, a bacterium? How would you trace it to its source?

That was the challenge facing the F.B.I., in 2001, when they saw their first real case of bioterrorism.

And, as correspondent Peter Standring reports, even microbes can leave telltale signs of their origin. But you've got to look awfully closely to see them, all the way down to single letters of their D.N.A.

PETER STANDRING (Correspondent): From the outside, this could be just another science building at Northern Arizona University. The inside is another story.

You don't get in here without one of these suits, and a damn good reason. You might be studying, for instance, how plague spreads through colonies of prairie dogs, or how one of the most infectious bacterium in the world, Coxiella burnetii, gives rise to debilitating Q fever.

As for our excuse for being here, it's to tell the story of how scientists, in this lab and across the country, participated in one of the most extensive criminal investigations ever, and, in the process, not only solved a mystery, but helped launch a new kind of science: "microbial forensics."

Our story begins just after 9/11, with the wreckage at Ground Zero still fresh and Americans confronting the possibility they are under attack again.

Evidence came first from a local hospital in Boca Raton, Florida. A photo editor of a tabloid newspaper, Robert Stevens, was dying from inhalation anthrax. He might have contracted it naturally; found in soil, anthrax, a spore-forming bacterium will, on occasion, infect a human. But it has also been turned into a deadly biological weapon, and Stevens had received a letter with a strange powder—facts which brought in the FBI.

THOMAS DELLAFERA (U.S. Postal Inspection Service): When Mr. Stevens turned up sick, in late September, early October, there was concern, certainly, that he had anthrax, but on the tails of the 9/11 attacks, the radar antennas were up and investigators were monitoring that situation.

PETER STANDRING: The F.B.I. rushed anthrax from Stevens's body to biologist Paul Keim at Northern Arizona University. Two years earlier, Keim had invented a test to distinguish one strain of anthrax from another.

PAUL KEIM (Northern Arizona University): So my laboratory and my research program had been focusing on anthrax for about 10 years prior to the attacks in 2001. We were the experts on anthrax types, and we had collections of anthrax from all around the world.

PETER STANDRING: Keim set out to match the anthrax killing Stevens with one of the 88 strains in his collection. As he compared fragments of D.N.A. for eight genetic markers, one strain stood out.

RESEARCHER: As you can tell, for each one of these markers, they line up exactly all the way across.

PAUL KEIM: And what we found, of course, was that this strain, this type of anthrax, was known to be a highly virulent strain being used by the U.S. Army for vaccine studies. And it was called the Ames strain.

PETER STANDRING: Isolated from a Texas cow, in 1981, the strain had been sent to Fort Detrick, Maryland, home of the U.S. Army Medical Research Institute of Infectious Disease. But it didn't stay at USAMRIID. Researchers, intrigued by its virulence, passed it from lab to lab,

which made a lab the most likely source of Stevens's infection.

ALAN ZELICOFF: And for people who study the biological weapons problem, the first thought that most of us had was that this was likely a state-sponsored intentional effort to cause harm, in an already-chaotic situation, in the United States.

PETER STANDRING: That suspicion grew as four more letters laced with anthrax turned up at the New York Post, NBC's New York headquarters and the U.S. Senate. The enclosed notes seemed to leave no question about their origins.

By late November, 22 people had been infected; five were dead.

It seemed certain terrorists had acquired anthrax, weaponized to disperse easily. But from where? We might never have known, except for one crucial development.

Now, if you think back to those dark days in 2001, you may recall that the anthrax attacks and 9/11 weren't the only events making headlines. In fact, a huge scientific achievement, only recently considered impossible, was shining just over the horizon.

Scientists stood on the verge of reading the entire human genetic code or genome, three billion letters of D.N.A., represented here by As, Cs, Gs and Ts. Together, these four chemical letters spell out instructions for making every living thing.

Since the D.N.A. of other species was also being read, the F.B.I. began to wonder if the new science of genomics might hold the key to the anthrax mystery.

They approached The Institute for Genomic Research, in Rockville, Maryland. Known as TIGR, the institute had already decoded the D.N.A. of several microbes.

CLAIRE FRASER-LIGGETT (University of Maryland School of Medicine, Institute for Genome Sciences): And the work that we proposed was to do an initial comparison between the D.N.A. sequence from the anthrax bacterium that killed Mr. Stevens and the original Ames anthrax bacterium that was collected in 1981.

PETER STANDRING: Never before had two entire genomes of a species been compared at every unit of their D.N.A. It meant matching up five million chemical letters, over 5,000 genes. The hope was that the Ames strain had mutated as it passed from lab to lab, and those mutations could be used to identify where the attack anthrax had come from.

While TIGR went to work, the F.B.I. began to collect samples from all the labs working with Ames anthrax.

THOMAS DELLAFERA: We went to the C.D.C. to identify all the laboratories that were authorized to work with pathogens; we went to publications to identify individuals who had worked with anthrax. At some point in early 2002, we'd identified a total of roughly 99 labs, worked our way down to where we ended up with 16 domestic labs and three foreign labs.

After months of work, investigators at TIGR could finally compare the two Ames genomes: the original sample from the cow and the anthrax used in the attacks.

JACQUES RAVEL (University of Maryland School of Medicine, Institute for Genome Sciences): So, to our disappointment, when we finished those two genomes—a quarter million dollars spent on each one—and we just did not find any difference.

CLAIRE FRASER-LIGGETT: Essentially all five-million-plus letters in these two genomes were identical. And at that point, I think the same thought was running through everybody's mind. And that was that perhaps this was going to end up as a dead-end.

PETER STANDRING: And there our story might have ended, except that one month later, a researcher at USAMRIID, using the sort of sharp-eyed observation that Sherlock Holmes would have admired, noticed something almost unnoticeable: among the colonies of attack anthrax being grown in Petri dishes, the color and shape of some looked slightly different.

JACQUES RAVEL: And we thought this could be the way to crack the case. We knew that those differences had to be linked to a genetic difference. And we went after those genetic differences.

PETER STANDRING: Four types of odd-looking colonies, known as morphs, were separated out, so their D.N.A. could be extracted and sequenced. Months and millions of dollars later, the results were in.

JACQUES RAVEL: What you can see here, after comparing the genome of some of the morph, and, in this case, morph D, what you can see is that the genome of morph D is missing a large portion.

PETER STANDRING: Remarkably, three involved only altering a single chemical letter of D.N.A.

JACQUES RAVEL: If you look at morph A, we change from a C to an A; and in morph B, a T to a C; and in morph C, a G to an A.

PETER STANDRING: So the only difference then, between morph A, B and C here and the ancestral Ames strain, is this one letter?

JACQUES RAVEL: It's one letter, only one, out of the 5.2 million letters that makes the genome.

PETER STANDRING: That's a very subtle change.

JACQUES RAVEL: Extremely subtle. And a lot of people, you know, when they looked at it, could have said it's just an error in a sequencing.

PETER STANDRING: So this was the beginning of being able to trace back the attack anthrax to its origins?

JACQUES RAVEL: Exactly. We finally had a combination of signatures that was extremely unique to the anthrax used in the attack.

PETER STANDRING: Searching for four mutations, the F.B.I. began testing the samples it had collected from labs working with Ames anthrax.

CLAIRE FRASER-LIGGETT: It turns out that only eight out of the nearly 1,100 samples contained all four of the genetic mutations that had been associated with the anthrax sent through the mail.

THOMAS DELLAFERA: We then went back to those researchers, investigated the source of those samples, and determined they all came from a particular spore sample known as RMR-1029.

PETER STANDRING: The flask labeled "RMR-1029" was traced to an army lab at USAMRIID. Its keeper: a senior biodefense researcher named Bruce Ivins. Was he the perpetrator? Ask the F.B.I., and you will hear no doubt.

THOMAS DELLAFERA: I can say with certainty that every member of the taskforce is convinced it was Dr. Ivins, and, unfortunately, we are never going to get our day in court.

PETER STANDRING: The reason? Ivins committed suicide after he became the prime suspect in the case. But others doubt Ivins could have made the anthrax used in the attacks.

ALAN ZELICOFF: It's not easy to do openly, particularly in a place like USAMRIID, where there are many people around and where, I think, there's a very strict protocol associated with working with any dangerous pathogen.

PETER STANDRING: Moreover, not a single spore was ever recovered from Ivins's property.

CLAIRE FRASER-LIGGETT: I don't think the science will ever be able to say who the perpetrator was. The best the science would ever be able to do would be to lead investigators back to a potential source.

On Screen Text: Anthrax has been found to exist on all continents except Antarctica. But in 1912, polar explorer R.R. Scott may have brought it with him, probably through infected ponies.

The evidence? Scott's hut, 90 years later: scientists found anthrax D.N.A.

AUTO-TUNE

NEIL DeGRASSE TYSON: "Our love was like a supernova,"

Yeah, I sing.

"In the nebula of my soul."

Okay, I'm not great.

"But now I find her heart is like a big black hole."

All right, I'm terrible. But here's what I'm wondering: if, digitally, you can remove red-eye, smooth over wrinkles, make people look thinner, then why don't we have the technology to make me sing better?

ANDY HILDEBRAND (Antares Audio Technologies): We can fix Neil.

NEIL DeGRASSE TYSON: This guy invented a way to do it.

ANDY HILDEBRAND: We can fix Neil's pitch. He's still going to sound like Neil, though.

NEIL DeGRASSE TYSON: Electrical engineer and inventor Andy Hildebrand designs pitch-correction software. He calls it Auto-Tune.

"Pitch correction?" Is that a euphemism for "fixing bad singers?"

ANDY HILDEBRAND: Yes, we fix bad singers.

NEIL DeGRASSE TYSON: I visited Andy at Antares Audio Technologies in Scotts Valley California, where he and engineer Justin Malo...

JUSTIN MALO: Hey, Neil.

NEIL DeGRASSE TYSON: ...showed me how it works.

Hummmmmmmmmm.

ANDY HILDEBRAND: Great. There you go. You did that.

NEIL DeGRASSE TYSON: That wavy line represents the exact frequency of my voice. This line shows where a perfect A should be, so, not too bad.

ANDY HILDEBRAND: He's right dead nuts on in tune. Look at that.

NEIL DeGRASSE TYSON: So how does a computer know that?

ANDY HILDEBRAND: When you hear A, you're hearing 440 vibrations per second.

NEIL DeGRASSE TYSON: So somebody at the beginning of time said 440 vibrations per second is an A?

ANDY HILDEBRAND: A.

NEIL DeGRASSE TYSON: So, if you sing or play a pitch at 440 cycles per second, the computer calls it an A and it rests on this line. B-flat would go on the line above it, G-sharp below, and so on.

"But now I find her heart..."

When you're out of tune, the notes don't fall so neatly onto the lines of the grid.

"...big..."

That's awful.

"...black hole."

ANDY HILDEBRAND: Well, it's creative, it's creative. Okay.

NEIL DeGRASSE TYSON: "...supernova..."

Those lines are me singing the word "super."

"supernova..."

My pitch is all over the place. If anything, it's closest to this note, here.

JUSTIN MALO: Neil, you sang an F, which normally is okay, if you're in the key of F. And we're not, so we moved your F to an E.

NEIL DeGRASSE TYSON: "Supernova..."

So Justin gently nudges it down to where an E would be.

"Supernova..."

You're changing the frequency of the sound that came out of my vocal cords.

JUSTIN MALO: Actually, yes.

ALVIN AND THE CHIPMUNKS (Audio recording): "Christmas, Christmas..."

NEIL DeGRASSE TYSON: Changing pitch isn't new. You can change someone's voice by fast forwarding on a tape recorder, but you'd sound like...

ALVIN AND THE CHIPMUNKS (Audio recording): "Christmas, Christmas time is here."

NEIL DeGRASSE TYSON: ...well, a chipmunk.

Pitch correction software lets you change the pitch...

"Supernova..."

...while keeping the essential tone of a voice the same.

And so, although few engineers are willing to admit it, pitch correction software, like Auto-Tune, has become an indispensable tool in most recording studios.

ANDY HILDEBRAND: It's been used by a lot of people: Madonna...

MADONNA (Film clip): "Music makes the bourgeoisie..."

NEIL DeGRASSE TYSON: ...Celine Dion...

CELINE DION (Film clip): "You got one heart you are following..."

NEIL DeGRASSE TYSON: Reba McEntire uses it live?

REBA McENTIRE (Film clip): "Starting over again..."

NEIL DeGRASSE TYSON: You're telling me a singer can sing into a microphone a bad note, and out the speakers comes a good note?

ANDY HILDEBRAND: Yes.

NEIL DeGRASSE TYSON: Now, that's evil.

ANDY HILDEBRAND: To modify something isn't necessarily evil. My wife wears makeup. Is that evil?

Is that okay, honey?

NEIL DeGRASSE TYSON: Evil or not, the recording industry kept Auto-Tune on the down-low.

ANDY HILDEBRAND: The secret popped out of the bag when Cher did "Believe."

CHER (Film clip): "Do you believe in life after love?"

ANDY HILDEBRAND: I couldn't believe it.

CHER (Film clip): "...aside and I can't break through..."

NEIL DeGRASSE TYSON: Rather than gradually and naturally reaching up to each note...

CHER (Film clip): "I can feel something inside me say..."

NEIL DeGRASSE TYSON: ...like this, Cher's producer forced Auto-Tune to jump suddenly from one pitch to the next.

CHER (Film clip): "I feel something inside me say..."

NEIL DeGRASSE TYSON: Is this some knob that you turn?

ANDY HILDEBRAND: Yes.

NEIL DeGRASSE TYSON: All right.

ANDY HILDEBRAND: And we can turn this knob to zero, which means "move instantaneously to the new pitch." And so, if we do that, your voice would sound like this.

NEIL DeGRASSE TYSON: "But now I find her heart..."

Did you plan for people to use it that way?

ANDY HILDEBRAND: No. I didn't think anybody in their right mind would ever use it that way.

NEIL DeGRASSE TYSON: Well a lot of artists do.

T-PAIN (Film clip): "She got me doing the dishes

Anything she want for some kisses"

OJO (Film clip): "I was young and in love..."

SNOOP DOG (Film clip): "She might be with him but she's thinkin' bout me, me, me."

NEIL DeGRASSE TYSON: But it's mostly used to tweak out-of-tune performances—a kind of cosmetic surgery.

"...big black hole."

In my case though, more like triple-bypass.

ANDY HILDEBRAND: Try to change this to the key of C.

NEIL DeGRASSE TYSON: Moving the traces of my voice up in pitch or down...

"...supernova..."

...Justin coaxes me into tune.

"Supernova

of my soul..."

It took several hours.

"...of my soul..."

How well did it work? You be the judge.

"Our love was like a supernova

In the nebula of my soul, but now I find

her heart is like a big black hole..."

JUSTIN MALO: It's a lot more pleasing.

NEIL DeGRASSE TYSON: I thought the first one sounded pretty good myself, I don't know.

Kidding aside, there's no substitute for training or talent.

ANDY HILDEBRAND: If the singer doesn't have a good tonality to their voice, we're not going to make that better.

Do us a favor. Don't go on American Idol.

PROFILE: LUIS VON AHN

NEIL DeGRASSE TYSON (As Game Show Host): Welcome to Find that Robot! the show where our electronic bachelorette tries to guess which of our three mystery contestants is not human, because sometimes, like on the Internet, the difference is not obvious.

BATCHELORETTE COMPUTER: Bachelor Number One, what is your idea of the perfect date?

NEIL DeGRASSE TYSON (As Bachelor Number One): I'd take you to the finest restaurant, and I'd recite love poems to you while we sip expensive champagne.

BATCHELORETTE COMPUTER: Hmmm; I don't drink. Bachelor Number Two?

NEIL DeGRASSE TYSON (As Bachelor Number Two): We would take a long walk on the beach, watch a beautiful sunset, and I'd learn all about you by moonlight.

BATCHELORETTE COMPUTER: Great. Bachelor Number Three, what is your idea of the perfect date?

BACHELOR NUMBER THREE COMPUTER: The perfect date is June 23, 1912.

BATCHELORETTE COMPUTER: He's the one!

NEIL DeGRASSE TYSON (As Game Show Host): Oh, what a lovely couple.

(As himself) In this episode's profile, we'll meet a guy who not only invented a way for a computer to spot another a computer, but a way to do it that will actually help mankind.

Luis von Ahn may seem like a slacker. He loves watching television.

LUIS VON AHN: I watch a lot of TV. That's how I spend most of my time outside of work. If I had more time, I would fill it 100 percent with watching TV. Right now I'm watching Heroes, Dexter and Fringe. Weeds, I've been watching Weeds, as well.

NEIL DeGRASSE TYSON: When he's not watching TV, Luis is playing games.

LUIS VON AHN: I definitely play some games, like Nintendo D.S. or the Wii, and some computer games.

LAURA DABBISH (Luis von Ahn's Fiancee): Luis is the kind of person who gets a game, and he wants to beat the game, you know? Play it nonstop until he beats it.

NEIL DeGRASSE TYSON: Luis even calls everybody "dude."

LUIS VON AHN: That's a really good trick, if you don't know their name. Just like, "Dude." And then they're like, "Dude."

NEIL DeGRASSE TYSON: But Luis is no slacker. He's a hotshot Carnegie Mellon computer science professor. He drives a Porsche. And, at age 30, he's quickly raced to the top of his field. You may have read about him. And you've almost certainly used his cutting edge computer programs. So when Luis watches TV and plays games, he's actually doing serious research.

PETER LEE (Carnegie Mellon University): I don't think it's relaxation for him. In fact, I've never known him to relax. He is a sponge, just trying to understand what motivates this social animal, which is the masses.

NEIL DeGRASSE TYSON: And unbeknownst to you, you're probably already working for Luis: fighting spam, digitizing books and labeling images on the Web. You're part of Luis' master plan to mobilize the largest workforce in the history of mankind; the hundreds of millions of people who use the Internet.

LUIS VON AHN: One of the things that I'm trying to figure out is, what can we do with this many people? What can you do when you can get 100 million people working on the same thing? And I think we can do amazing things.

NEIL DeGRASSE TYSON: As for the source of his ideas, Luis is a human think tank.

LUIS VON AHN: I guess I'm a big pacer. I pace when I do most things. So yeah, when I'm trying to think or solve a problem, I pace around.

LAURA DABBISH: Any time he has a problem, and he's, sort of, ruminating over the problem, that's what he does. You would see him walk up and down that hallway 20 times a day. He can take a problem that seems impossible and just sort of see the solution, see through it.

LUIS VON AHN: I have multiple ideas per day, all the time. The vast majority of these are completely idiotic. Usually, I just sit on the idea for several months. And if I have not decided that it's idiotic, then it's...might be a good idea.

NEIL DeGRASSE TYSON: Luis' first big idea came when he and his adviser, Manuel Blum, were approached by Yahoo!.

MANUEL BLUM (Luis von Ahn's Ph.D. Advisor): The chief scientist at Yahoo! told us he had a problem.

NEIL DeGRASSE TYSON: The problem was spam, and it was clogging up Yahoo!. Spammers needed a vast number of email accounts to send their spam, and they were using automated computer programs to sign up for them.

LUIS VON AHN: Spammers were writing programs to obtain millions of Yahoo! email accounts every day, because they wanted to send spam.

NEIL DeGRASSE TYSON: Luis and Manuel needed a way to tell the difference between a well-meaning Yahoo! subscriber, and a malicious spam computer program.

LUIS VON AHN: We came up with this idea of trying to give a test to figure out whether it's a human or not.

It's got to be a computerized test, given to humans and computers. So the computer must be able to grade a test that it cannot pass. You know, it looks paradoxical.

NEIL DeGRASSE TYSON: What Luis and Manuel developed was a CAPTCHA, a secret password that people can read, but computers can't.

MANUEL BLUM: The computer can take some characters, and it can put them on a rubber sheet, and they can then stretch this sheet and pour paint on it, and change the looks of these characters, to the point where it can no longer see the original characters, and then can put it out there knowing that humans are still very good at being able to recognize this.

NEIL DeGRASSE TYSON: So using CAPTCHA, people could sign up for Yahoo! accounts, but automated spam programs could not. CAPTCHA has spread across the web. It's now used by most major websites.

PETER LEE: CAPTCHA has had this amazing impact. There are fairly good estimates that more than 750-million different people in the world have solved at least one CAPTCHA.

NEIL DeGRASSE TYSON: Luis' resourcefulness and his quest for efficiency go back as far as he can remember, as a boy growing up in Guatemala, where his family owned a candy factory.

LUIS VON AHN: I think growing up in a candy factory has influenced me. It's quite a complex process, the machines of making the candy and wrapping it and everything. I always wondered how all of those machines worked.

NEIL DeGRASSE TYSON: At the age of seven, Luis even built his own machine, to do his homework faster.

LUIS VON AHN: I was taking a penmanship class. The assignments were to draw a lot of ovals, like, a gazillion ovals. And that was really boring. So what I did, is I put, like, five pens together. I was just using that one thing with the five pens and it was going five times faster. Of course, I got caught. But it was great while it lasted—doing my homework in 20 minutes as opposed to an hour and a half.

NEIL DeGRASSE TYSON: Twenty years later, Luis applied this same kind of efficiency to the time wasted typing in CAPTCHAs.

LUIS VON AHN: I started feeling bad, because each time you type a CAPTCHA—you know, the squiggly characters—essentially, you waste 10 seconds of your time. And if you multiply that by 200 million, you get that humanity as a whole is wasting, like,

500,000 hours every day, typing these annoying CAPTCHAs. I started thinking, is there a way in which we could use this human effort for something that's good for humanity? Can we make good use of those 10 seconds of your time?

NEIL DeGRASSE TYSON: Luis struggled with this question. And then he got involved with an even bigger project: putting all the old books in the world onto the Internet.

LUIS VON AHN: There's a lot of projects out there trying to digitize books; Google has one, the Internet Archive has another one.

NEIL DeGRASSE TYSON: But there's a problem. Many of the books are old and faded, so when the computers scan them, they don't recognize many of the words.

LUIS VON AHN: For things that were written before 1900, between 30 percent and 40 percent of the words, the computer is going to decipher wrong.

MANUEL BLUM: They were written at a time when the type didn't line up always nicely, and what remnants we have of it are smudged.

NEIL DeGRASSE TYSON: Luis's solution was to take these hard to read words from old books and use them as CAPTCHAs.

But this raised a new problem, the computer would now present a word that it could not read in the first place.

MANUEL BLUM: The computer didn't know what the answer was. How is it to be able to tell what the right answer is?

NEIL DeGRASSE TYSON: Luis found a solution: to combine the word from an old book with a traditional CAPTCHA generated by the computer.

MANUEL BLUM: We'll give two tests, one that we know the answer to, one that we don't. And if the person can solve the one that we know the answer to, then we'll assume they can solve the one that we don't.

NEIL DeGRASSE TYSON: They called it reCAPTCHA. Now, every time you type a CAPTCHA, you may very well be working for Luis, transcribing an old book.

PETER LEE: Today, on the order of 125 to 150 books per day are being digitized because of reCAPTCHA. It's an amazing thing.

NEIL DeGRASSE TYSON: And it's not just books. ReCAPTCHA is also transcribing the entire back archive of The New York Times.

LUIS VON AHN: The New York Times has this huge archive of 130 years of newspaper archived there. And we've done, maybe, about 20 years so far of The New York Times in the last few months. And I believe we're going to be done next year, by just having people do a word at a time.

NEIL DeGRASSE TYSON: With CAPTCHA and reCAPTCHA under his belt, Luis was a hot commodity when he graduated with his Ph.D. from Carnegie Mellon.

PETER LEE: He became this, kind of, sensation. People immediately understood that there was something very new here.

LUIS VON AHN: I had offers from Microsoft and Yahoo! and all kinds of companies. For the Microsoft offer, they even had Bill Gates call me.

NEIL DeGRASSE TYSON: But Luis wanted to become a professor.

LUIS VON AHN: I did turn my back on a lot of money. But in the end, I decided that I liked the academic job better.

NEIL DeGRASSE TYSON: Just days after taking a teaching job at Carnegie Mellon, Luis won the half-million dollar MacArthur Fellowship.

LUIS VON AHN: When I found out that I had won the MacArthur Fellowship, I had been a professor at Carnegie Mellon for a week. I probably shouldn't be saying this on TV, but I stopped worrying about tenure. Please give me tenure.

NEIL DeGRASSE TYSON: And it's not just the genius grant that may help Luis get tenure.

PETER LEE: Luis von Ahn is one of our very best teachers. In fact, last year he won one of the top awards for teaching here at Carnegie Mellon.

LUIS VON AHN: So my philosophy for teaching is, make it interesting or fun or just keep them engaged. That's the most important thing. Secondary to that is teaching them something.

On Screen Text: Okay, wait a minute. Rewind, please.

BACHELOR NUMBER THREE COMPUTER: "The perfect date is June 23, 1912."

What's so special about June 23, 1912? You tell us. Go to pbs.org.

Cosmic Perspective: Carbon

NEIL DeGRASSE TYSON: And now for some final thoughts on carbon.

You might think of carbon as kind of an unpleasant little element. After all, it's the active ingredient in soot. It's also the stuff left over after you burn your toast.

But it's actually quite distinguished among elements. Carbon has the highest melting point. Pure carbon can become graphite, one of the softest materials around, used every time you write with a pencil. Meanwhile, pure carbon, when exposed to heat, pressure and a little bit of time, also makes diamond, one of the hardest materials around, used for the cutting tips of masonry saws and jackhammers.

Perhaps you didn't know, but when light passes into a diamond, it slows down to only 40 percent of its speed in a vacuum. Oh, and did I mention you can use diamonds to make jewelry?

But carbon's greatest distinction of all is that it's the building block for the molecules of life. Carbon is remarkably fertile. You can make more molecules with carbon in them than you can with all other kinds of molecules combined.

So we shouldn't be surprised that life—the most complex expression of chemistry we know—is based on carbon.

And because carbon is the third most abundant chemically active ingredient in the universe, right after hydrogen and oxygen, we're given every reason to presume that yet-to-be-discovered life, elsewhere in the cosmos, would be based on carbon as well.

So what would we do? Where would be without carbon? Jewelry would be a lot less interesting. But that would be the least of our concerns, since life itself probably would not exist at all.

And that is the cosmic perspective.

And now we'd like to hear your perspective on this episode of NOVA scienceNOW. Log on to our Web site and tell us what you think.

You can watch any of these stories again, download additional audio and video, explore interactives, hear from experts, and much more. Find us at pbs.org.

That's our show. We'll see you next time. Stay tuned for scenes from the next NOVA scienceNOW, but first...

Funding for NOVA scienceNOW is provided by The National Science Foundation, where discoveries begin. And...

Discover new knowledge; biomedical research and science education; Howard Hughes Medical Institute: HHMI.

And the Alfred P. Sloan Foundation to enhance public understanding of science and technology and to portray the lives of men and women engaged in scientific and technological pursuit.

And the George D. Smith Fund.

And by PBS viewers like you. Thank you.

This NOVA program is available on DVD. To order, visit shoppbs.org, or call us at 1-800-PLAY PBS.

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