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They're dazzling, priceless...
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at times, even glowing.
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How can one not fall in love with rocks and minerals?
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I mean, the colors, the shapes...
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...and they're the building blocks of modern civilization.
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We wouldn't have televisions, we wouldn't have automobiles, we wouldn't have
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buildings without the mineral riches that we have.
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But could rocks and minerals also solve
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the greatest mystery of all time?
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The origin of life.
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The rocks we pick up tell a story
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that life couldn't have occurred without rocks.
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Could cold, lifeless stone hold the key
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to every living thing on Earth?
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From Australia, to Morocco,
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Nova goes around the world and back in time
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to investigate the origin and evolution of life.
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Look at a rock and you think ah, well, nothing.
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but this holds the signature of life.
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From its first spark...
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People were saying they've made Frankenstein in a test tube...
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...To the survival of the fittest.
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These were immense creatures. Sharks that may have been 50 or 60 feet.
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Was it the secret link between rocks and life
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that made the difference?
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Life's rocky start. Right now, on Nova.
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The ancient market of Marrakech,
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a chaotic, colorful gathering place teeming with life for thousands of years,
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the perfect place to ask how did this exotic, beautiful and sometimes bizarre
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thing called life, begin?
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How did Earth go from a lifeless, molten rock...
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to a living planet?
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Full of diverse and spectacular creatures.
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it's a question that has long perplexed scientists.
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Now, Robert Hazen, a geologist, is trying to show we are missing an essential
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ingredient in the recipe for life.
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-look at that vein of calcite...
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Rocks.
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Nothing seems more lifeless than a rock.
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it's inanimate, it's the antithesis of a living thing, but we're beginning to
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realize that rocks played an absolutely fundamental role in the origin of life.
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Hazen is out to expose a secret relationship between rocks and life that
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helped drive both the origin of life and its evolution into complex creatures.
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This is a very new set of understandings and the more we look, the more we see
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that life depends on rocks, rocks depend on life.
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This has been going on for four billion years.
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As a geologist, it's no surprise
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that Hazen is searching for answers written in stone.
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But is he right?
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Are rocks the missing spark of life?
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The history of Earth is unimaginably long.
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If it were sped up to the equivalent of a single day, all of humankind from the
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earliest skeletons to the invention of the iphone would have occurred in only
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the last four seconds.
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Dinosaurs were still roaming earth about 20 minutes before that,
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but the creation of our planet occurred more than 23 hours earlier, two cycles on
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this clock
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or 4.5 billion years ago.
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Comprehending Earth's vast history is a formidable task.
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It is four and a half billion years of change, but you can divide it into half a dozen ways of
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describing Earth through time.
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Bob Hazen has come up with another way to visualize Earth's long history that
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reveals this special relationship between rocks and life.
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He has divided it into six stages, each represented by a different color
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to understand how we ended up with green earth, the planet we now know, requires us
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to turn the clock back to before there was any life at all.
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Stage one was the creation of black Earth.
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Back in Morocco, Hazen and Adam Aaronson, a meteorite expert, seek out a small rock
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from the beginning of our cosmos.
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-Wow look at this pile here. -yeah.
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These are meteorites. Rocks that have fallen from space.
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-This is Tamta. This is the one that fell 20 kilometers up the road from here.
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People saw it fall.
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A recent meteorite fall in Siberia was captured in videos that have shown up on Youtube.
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Other space rocks have ended up for sale here in Morocco.
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-Say you'd buy this without doing tests...
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-I'll drop the cash right now here and give me a good price.
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Meteorites here can sell
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for tens of thousands of dollars. That may seem a steep price for a lump of
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rock, but these are some of the very oldest objects in our solar system.
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This is the oldest object you could ever hold in your hand. It's 4.6 billion years
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old and is formed before Earth formed. This is the very first solid material,
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the very first rock in our solar system and these came together to build all the planets.
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Our Earth was created out of the rocks and dust present at the start of our solar system.
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Over time, small fragments of orbiting rock collided, coming together into the
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planet circling the Sun.
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At first, Earth was molten with temperatures in the thousands of degrees,
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but in the cold vacuum of space this hot rock began to cool and change.
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Nothing.
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Not a speck of dust is believed to have survived from the period of black Earth.
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It was a hellishly unpleasant time.
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Volcanoes spewed hot lava from deep inside the planet.
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When it cooled, it covered Earth with its first rock called basalt
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and it was black.
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It seems like a desolate landscape, but some ingredients that life will need are
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already here in these rocks.
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Look inside and you begin to understand how intriguing
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even an ordinary rock is.
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Every rock, you slice it open
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you look inside, there's something special. Rocks are made up mostly of
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minerals, which are crystals like quartz or diamonds. Looking through a microscope
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at super thin slices of a rock lets you see its mineral composition.
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This is the rock Peridotite, made up of small crystals, including olivine and pyroxene.
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Even a simple black basalt rock, spewed from a volcano, becomes a
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patchwork of colorful minerals.
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It's sort of like a fruitcake, you know I slice it open, there's nuts and there's
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dried fruit and maybe some lemon peel.
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It's made of lots of little things and it is not until you slice into that fruitcake
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that you see all the stuff inside that makes it special.
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What makes them special is not only their beauty. Minerals have remarkable
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chemical and physical properties and are a source of many of the elements -
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nature's building blocks.
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That is why they are essential in our modern world to make everything from
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skyscrapers taller
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- mobile phones smaller.
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Extract the element molybdenum from the mineral molybdenite to make steel stronger.
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Or add a pinch of cobalt and your iphone battery will last longer.
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Minerals are the fundamental building block of societies. We wouldn't have
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televisions, we wouldn't have automobiles, we wouldn't have buildings without the
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mineral riches that we have.
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So, were the remarkable chemical properties of minerals also key in
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creating life?
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If so, Earth would mean more than it started with
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It's estimated that the meteorites that formed Earth had only about 250 minerals,
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sort of a chemical starter kit, containing many of the elements.
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Then, in the intense heat and pressures in the creation of our planet, new
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minerals began to form. This changed the appearance of our Earth from black to
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gray.
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Yosemite national park is a relatively new piece of Earth,
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but the kind of rock that makes up these dramatic cliffs goes back much further.
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These huge walls are granite containing minerals like quartz and feldspar.
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Granite became the foundation of our continents, leading Earth into the gray period.
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At this point, earth is still a long way from the glorious diversity of plants
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and animals that makes Yosemite so picturesque.
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But the stage is set for the next character in our planet story:
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Water, which will turn Earth blue. Water plays a central role in every model for
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the origin of life.
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That's because water is such a great solvent. All these different kinds of
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molecules can be floating around the water and then they have the potential to
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interact together. The starting point is the water.
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So when did Earth cool enough to have liquid water,
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this element key to life?
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One of the biggest unknowns in this whole idea of going from black to gray
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to a blue water-covered earth, is how quickly it happened.
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The timing is a big mystery.
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The Pilbara in Western Australia is one of the oldest places on Earth
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and so, one of the best places to solve the mystery of the planet's first oceans.
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Hazen joins an all-star team of geologists, including Martin Van Kranendonk
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from the University of New South Wales and John Valley of the University
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of Wisconsin.
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Valley is collecting rocks that could hold clues to when water first appeared.
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We could get zircons and other minerals that date all the way back to
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4.4 billion years old.
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Hopefully.
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Some rocks here contain sand-sized grains that wheathered from even older rocks.
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one in a million, literally, is a crystal called zircon, one of the longest lasting
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materials in nature.
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Zircon is a popular gemstone, but the microscopic zircon found here is even
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more precious.
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Zircon crystals are especially amazing. Gemstone zircons of course are valued, but
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these tiny ones the geologists value are microscopic that make a lousy ring, but
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they tell an incredible story.
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To tell that story, John Valley must first find the tiny crystals,
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the ultimate needle in a haystack.
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If you want to find a needle in a haystack, the first thing you do is you
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burn down the haystack.
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Then you sip through the ash to look for the needle. Rocks are pulverized into
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sand sized grains and sorted by weight in a machine developed to pan for gold.
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The gold that Valley is looking for are heavy zircon crystals which get
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channeled into different tracks.
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Then, grain by grain, with a very steady hand,
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thousands of small crystals are sorted and analyzed.
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The chemical structure of a zircon crystal holds evidence of both the environment
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and the age when it formed.
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Some of these tiny crystals go very far back,
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just over a hundred million years after Earth formed.
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They are the oldest pieces of Earth ever discovered.
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So they could shed light on what our young planet looked like.
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It's totally amazing. To hold this grain of sand in the palm of your hand
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is literally to see back through time.
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It is a time machine.
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Valley expected these crystal time machines would confirm the long-held
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view that the young Earth was covered in molten lava, still cooling after its
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violent formation.
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I think the zircon on the left looks very promising.
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So what he discovered was shocking, because this type of zircon created 4.3
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billion years ago could only have formed in the presence of liquid water.
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But how could there be water if Earth was still hot and hell-like?
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The implications were that the early Earth had water,
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it was cooler and it was wet.
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It's starting to look very much more familiar.
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And if water is a key starting point for life
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could there be life that early too?
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The science of the zircon is telling us that the Earth for a very, very long time
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was a habitable environment, not necessarily that there was life then.
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We don't know that yet, but there's no reason why there couldn't have been life
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as early as 4.3 billion years ago.
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So, if life were possible that early, it begs the question: how did life begin?
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In 1871, Charles Darwin speculated in a letter to a friend that a warm little
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pond might be life's birthplace.
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A warm soup of chemicals bathed by energy from the Sun would have been, well,
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comfortable for molecules to come together in new ways and create life.
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Darwin was way, way ahead of his time.
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A nice little warm soup is gonna get you a long way.
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Jeff Boda of the Scripps Institution of Oceanography in San Diego has spent his
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career working to understand the early Earth's soup of chemicals.
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He began under the direction of perhaps the most famous scientist in origin of
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life research,
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Stanley Miller.
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There are in the history of science turning points where we suddenly see the
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history of Earth and life differently. In the early nineteen fifties, Stanley
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Miller, the eager graduate student, and Harold Urey, the Nobel Prize winning
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mentor at the University of Chicago conducted this astonishing experiment
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where they made an early Earth environment.
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It looks like this sort of a Frankenstein type apparatus, but actually
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it's a very carefully thought out design. Boda sets up a modern-day test of the
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nineteen fifties experiment on Miller's original lab equipment.
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One flask contains water. That's to simulate the ocean.
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The other flask has just got the gases in it, so this is the atmosphere.
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Just as it does in nature, water from the ocean evaporates and rises into the
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atmosphere, where it condenses and returns to the ocean.
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Miller simulated what he believed to be the atmosphere of early Earth with
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different gases like ammonia and methane.
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Then he added a spark of genius.
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Miller and Urey decided to use a spark to simulate lightning, because that's
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such a ubiquitous process in the atmosphere of the Earth.
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That was the real inspiration. These little electric sparks that acted like
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simulated lightning. The energy from the spark of lightning breaks down the gas
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and water molecules so they can undergo further chemical reactions.
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To their astonishment, when they turn this apparatus on, after only a couple of days,
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you started seeing this pink color developing.
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In a few more days, black
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oily goo is forming around the electrodes.
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The electrodes get covered with new substances.
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Organic compounds, usually associated with life.
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And it wasn't just any organic compound. It was amino acids that make proteins,
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the ingredients for life.
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Amino acids are the building blocks of life.
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They form proteins, which are the key component of muscles and other tissues.