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  • They're dazzling, priceless...

  • at times, even glowing.

  • How can one not fall in love with rocks and minerals?

  • I mean, the colors, the shapes...

  • ...and they're the building blocks of modern civilization.

  • We wouldn't have televisions, we wouldn't have automobiles, we wouldn't have

  • buildings without the mineral riches that we have.

  • But could rocks and minerals also solve

  • the greatest mystery of all time?

  • The origin of life.

  • The rocks we pick up tell a story

  • that life couldn't have occurred without rocks.

  • Could cold, lifeless stone hold the key

  • to every living thing on Earth?

  • From Australia, to Morocco,

  • Nova goes around the world and back in time

  • to investigate the origin and evolution of life.

  • Look at a rock and you think ah, well, nothing.

  • but this holds the signature of life.

  • From its first spark...

  • People were saying they've made Frankenstein in a test tube...

  • ...To the survival of the fittest.

  • These were immense creatures. Sharks that may have been 50 or 60 feet.

  • Was it the secret link between rocks and life

  • that made the difference?

  • Life's rocky start. Right now, on Nova.

  • The ancient market of Marrakech,

  • a chaotic, colorful gathering place teeming with life for thousands of years,

  • the perfect place to ask how did this exotic, beautiful and sometimes bizarre

  • thing called life, begin?

  • How did Earth go from a lifeless, molten rock...

  • to a living planet?

  • Full of diverse and spectacular creatures.

  • it's a question that has long perplexed scientists.

  • Now, Robert Hazen, a geologist, is trying to show we are missing an essential

  • ingredient in the recipe for life.

  • -look at that vein of calcite...

  • Rocks.

  • Nothing seems more lifeless than a rock.

  • it's inanimate, it's the antithesis of a living thing, but we're beginning to

  • realize that rocks played an absolutely fundamental role in the origin of life.

  • Hazen is out to expose a secret relationship between rocks and life that

  • helped drive both the origin of life and its evolution into complex creatures.

  • This is a very new set of understandings and the more we look, the more we see

  • that life depends on rocks, rocks depend on life.

  • This has been going on for four billion years.

  • As a geologist, it's no surprise

  • that Hazen is searching for answers written in stone.

  • But is he right?

  • Are rocks the missing spark of life?

  • The history of Earth is unimaginably long.

  • If it were sped up to the equivalent of a single day, all of humankind from the

  • earliest skeletons to the invention of the iphone would have occurred in only

  • the last four seconds.

  • Dinosaurs were still roaming earth about 20 minutes before that,

  • but the creation of our planet occurred more than 23 hours earlier, two cycles on

  • this clock

  • or 4.5 billion years ago.

  • Comprehending Earth's vast history is a formidable task.

  • It is four and a half billion years of change, but you can divide it into half a dozen ways of

  • describing Earth through time.

  • Bob Hazen has come up with another way to visualize Earth's long history that

  • reveals this special relationship between rocks and life.

  • He has divided it into six stages, each represented by a different color

  • to understand how we ended up with green earth, the planet we now know, requires us

  • to turn the clock back to before there was any life at all.

  • Stage one was the creation of black Earth.

  • Back in Morocco, Hazen and Adam Aaronson, a meteorite expert, seek out a small rock

  • from the beginning of our cosmos.

  • -Wow look at this pile here. -yeah.

  • These are meteorites. Rocks that have fallen from space.

  • -This is Tamta. This is the one that fell 20 kilometers up the road from here.

  • People saw it fall.

  • A recent meteorite fall in Siberia was captured in videos that have shown up on Youtube.

  • Other space rocks have ended up for sale here in Morocco.

  • -Say you'd buy this without doing tests...

  • -I'll drop the cash right now here and give me a good price.

  • Meteorites here can sell

  • for tens of thousands of dollars. That may seem a steep price for a lump of

  • rock, but these are some of the very oldest objects in our solar system.

  • This is the oldest object you could ever hold in your hand. It's 4.6 billion years

  • old and is formed before Earth formed. This is the very first solid material,

  • the very first rock in our solar system and these came together to build all the planets.

  • Our Earth was created out of the rocks and dust present at the start of our solar system.

  • Over time, small fragments of orbiting rock collided, coming together into the

  • planet circling the Sun.

  • At first, Earth was molten with temperatures in the thousands of degrees,

  • but in the cold vacuum of space this hot rock began to cool and change.

  • Nothing.

  • Not a speck of dust is believed to have survived from the period of black Earth.

  • It was a hellishly unpleasant time.

  • Volcanoes spewed hot lava from deep inside the planet.

  • When it cooled, it covered Earth with its first rock called basalt

  • and it was black.

  • It seems like a desolate landscape, but some ingredients that life will need are

  • already here in these rocks.

  • Look inside and you begin to understand how intriguing

  • even an ordinary rock is.

  • Every rock, you slice it open

  • you look inside, there's something special. Rocks are made up mostly of

  • minerals, which are crystals like quartz or diamonds. Looking through a microscope

  • at super thin slices of a rock lets you see its mineral composition.

  • This is the rock Peridotite, made up of small crystals, including olivine and pyroxene.

  • Even a simple black basalt rock, spewed from a volcano, becomes a

  • patchwork of colorful minerals.

  • It's sort of like a fruitcake, you know I slice it open, there's nuts and there's

  • dried fruit and maybe some lemon peel.

  • It's made of lots of little things and it is not until you slice into that fruitcake

  • that you see all the stuff inside that makes it special.

  • What makes them special is not only their beauty. Minerals have remarkable

  • chemical and physical properties and are a source of many of the elements -

  • nature's building blocks.

  • That is why they are essential in our modern world to make everything from

  • skyscrapers taller

  • - mobile phones smaller.

  • Extract the element molybdenum from the mineral molybdenite to make steel stronger.

  • Or add a pinch of cobalt and your iphone battery will last longer.

  • Minerals are the fundamental building block of societies. We wouldn't have

  • televisions, we wouldn't have automobiles, we wouldn't have buildings without the

  • mineral riches that we have.

  • So, were the remarkable chemical properties of minerals also key in

  • creating life?

  • If so, Earth would mean more than it started with

  • It's estimated that the meteorites that formed Earth had only about 250 minerals,

  • sort of a chemical starter kit, containing many of the elements.

  • Then, in the intense heat and pressures in the creation of our planet, new

  • minerals began to form. This changed the appearance of our Earth from black to

  • gray.

  • Yosemite national park is a relatively new piece of Earth,

  • but the kind of rock that makes up these dramatic cliffs goes back much further.

  • These huge walls are granite containing minerals like quartz and feldspar.

  • Granite became the foundation of our continents, leading Earth into the gray period.

  • At this point, earth is still a long way from the glorious diversity of plants

  • and animals that makes Yosemite so picturesque.

  • But the stage is set for the next character in our planet story:

  • Water, which will turn Earth blue. Water plays a central role in every model for

  • the origin of life.

  • That's because water is such a great solvent. All these different kinds of

  • molecules can be floating around the water and then they have the potential to

  • interact together. The starting point is the water.

  • So when did Earth cool enough to have liquid water,

  • this element key to life?

  • One of the biggest unknowns in this whole idea of going from black to gray

  • to a blue water-covered earth, is how quickly it happened.

  • The timing is a big mystery.

  • The Pilbara in Western Australia is one of the oldest places on Earth

  • and so, one of the best places to solve the mystery of the planet's first oceans.

  • Hazen joins an all-star team of geologists, including Martin Van Kranendonk

  • from the University of New South Wales and John Valley of the University

  • of Wisconsin.

  • Valley is collecting rocks that could hold clues to when water first appeared.

  • We could get zircons and other minerals that date all the way back to

  • 4.4 billion years old.

  • Hopefully.

  • Some rocks here contain sand-sized grains that wheathered from even older rocks.

  • one in a million, literally, is a crystal called zircon, one of the longest lasting

  • materials in nature.

  • Zircon is a popular gemstone, but the microscopic zircon found here is even

  • more precious.

  • Zircon crystals are especially amazing. Gemstone zircons of course are valued, but

  • these tiny ones the geologists value are microscopic that make a lousy ring, but

  • they tell an incredible story.

  • To tell that story, John Valley must first find the tiny crystals,

  • the ultimate needle in a haystack.

  • If you want to find a needle in a haystack, the first thing you do is you

  • burn down the haystack.

  • Then you sip through the ash to look for the needle. Rocks are pulverized into

  • sand sized grains and sorted by weight in a machine developed to pan for gold.

  • The gold that Valley is looking for are heavy zircon crystals which get

  • channeled into different tracks.

  • Then, grain by grain, with a very steady hand,

  • thousands of small crystals are sorted and analyzed.

  • The chemical structure of a zircon crystal holds evidence of both the environment

  • and the age when it formed.

  • Some of these tiny crystals go very far back,

  • just over a hundred million years after Earth formed.

  • They are the oldest pieces of Earth ever discovered.

  • So they could shed light on what our young planet looked like.

  • It's totally amazing. To hold this grain of sand in the palm of your hand

  • is literally to see back through time.

  • It is a time machine.

  • Valley expected these crystal time machines would confirm the long-held

  • view that the young Earth was covered in molten lava, still cooling after its

  • violent formation.

  • I think the zircon on the left looks very promising.

  • So what he discovered was shocking, because this type of zircon created 4.3

  • billion years ago could only have formed in the presence of liquid water.

  • But how could there be water if Earth was still hot and hell-like?

  • The implications were that the early Earth had water,

  • it was cooler and it was wet.

  • It's starting to look very much more familiar.

  • And if water is a key starting point for life

  • could there be life that early too?

  • The science of the zircon is telling us that the Earth for a very, very long time

  • was a habitable environment, not necessarily that there was life then.

  • We don't know that yet, but there's no reason why there couldn't have been life

  • as early as 4.3 billion years ago.

  • So, if life were possible that early, it begs the question: how did life begin?

  • In 1871, Charles Darwin speculated in a letter to a friend that a warm little

  • pond might be life's birthplace.

  • A warm soup of chemicals bathed by energy from the Sun would have been, well,

  • comfortable for molecules to come together in new ways and create life.

  • Darwin was way, way ahead of his time.

  • A nice little warm soup is gonna get you a long way.

  • Jeff Boda of the Scripps Institution of Oceanography in San Diego has spent his

  • career working to understand the early Earth's soup of chemicals.

  • He began under the direction of perhaps the most famous scientist in origin of

  • life research,

  • Stanley Miller.

  • There are in the history of science turning points where we suddenly see the

  • history of Earth and life differently. In the early nineteen fifties, Stanley

  • Miller, the eager graduate student, and Harold Urey, the Nobel Prize winning

  • mentor at the University of Chicago conducted this astonishing experiment

  • where they made an early Earth environment.

  • It looks like this sort of a Frankenstein type apparatus, but actually

  • it's a very carefully thought out design. Boda sets up a modern-day test of the

  • nineteen fifties experiment on Miller's original lab equipment.

  • One flask contains water. That's to simulate the ocean.

  • The other flask has just got the gases in it, so this is the atmosphere.

  • Just as it does in nature, water from the ocean evaporates and rises into the

  • atmosphere, where it condenses and returns to the ocean.

  • Miller simulated what he believed to be the atmosphere of early Earth with

  • different gases like ammonia and methane.

  • Then he added a spark of genius.

  • Miller and Urey decided to use a spark to simulate lightning, because that's

  • such a ubiquitous process in the atmosphere of the Earth.

  • That was the real inspiration. These little electric sparks that acted like

  • simulated lightning. The energy from the spark of lightning breaks down the gas

  • and water molecules so they can undergo further chemical reactions.

  • To their astonishment, when they turn this apparatus on, after only a couple of days,

  • you started seeing this pink color developing.

  • In a few more days, black

  • oily goo is forming around the electrodes.

  • The electrodes get covered with new substances.

  • Organic compounds, usually associated with life.

  • And it wasn't just any organic compound. It was amino acids that make proteins,

  • the ingredients for life.

  • Amino acids are the building blocks of life.

  • They form proteins, which are the key component of muscles and other tissues.