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So what is human existence?
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How can you actually sum it up?
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It turns out it's really pretty simple.
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We are dead stars, looking back up at the sky.
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Everything you are, I mean literally the iron in your blood, comes from the instant before a star dies.
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You cut yourself, and you see that red from that oxygenated hemoglobin.
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That was the instant of the death of a solar system.
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The universe began with only the element hydrogen,
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the very very simplest atom that exists.
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And the only thing in the universe that can make a bigger atom is a star.
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The entire periodic table, every element you ever heard of was processed inside the body of a star.
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That star then unravelled or exploded.
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And here we are.
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All a star is, is a dust cloud that is collapsing under the force of gravity.
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That's it. And when you compress gas together, it actually heats up.
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There's a time when that's hot enough to set off a nuclear fusion reaction.
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That actually supports the star.
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This nuclear explosion inside supports the star against further collapse.
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But that nuclear fusion reaction is using fuel, it's using hydrogen.
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And so eventually, that will burn out, and the collapse of gravity will keep going.
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In the case of a more massive star, the gravity crushes more and more tightly.
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Things get hotter inside, you create things like carbon, oxygen, nitrogen,
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until finally, you get to the element iron.
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It fuses iron together, and instead of energy coming out, energy is actually absorbed.
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And the core of the star collapses.
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And that sets off the most violent, brilliant reaction we know of called a supernova reaction.
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Everything outside the element of iron, everything heavier.
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All the gold, all the silver, all the lead, all the uranium.
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That's formed in that supernova explosion.
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A single star will glow as brightly as entire galaxies, that's hundreds of billions of stars, in that moment of death.
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And that's what you are.
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That literally what your body is...
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Is that instant of death.
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You know, it's so tempting. Humans have done this before, for literally tens of thousands of years.
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They think of the stars as eternal.
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Stars will all burn out someday.
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There's only a certain amount of stellar fuel, hydrogen.
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Stars are burning through it.
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And the stars, as we know them, will all die out in some trillions of years.
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And the universe will be dark, for the rest of time. Whatever that means.
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But think about that, we're actually living in Eden right now.
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We're living in a time when this ten-billion-year-lived thing, the sun,
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is pouring down free energy, we are using it, we are evolving,
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we are becoming sentient, we are looking out at the universe.
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And what an amazing thing to think that that's for a tiny little brief part of the universe's history.
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And everything else will be dark.
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It does give you an ownership, about how wonderful this time is.
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How wonderful your life is right now. Your literal life.
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But also how wonderful this time of the universe is.
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Someday I wonder, if people will have myths about the days when stars rained down free sunlight, free energy.