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[pensive music playing]
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00:00:14,120 --> 00:00:15,120
[Freeman] Nightfall…
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00:00:19,240 --> 00:00:22,880
reveals our planet's connection
to the universe.
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[whooshing]
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00:00:28,160 --> 00:00:29,560
A shooting star.
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Ancient rock from the depths of space…
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falling to Earth.
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Inside it are the chemical elements
that built our universe.
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[pensive music continues]
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[ethereal tinkling]
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For countless generations,
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sea turtles have roamed the oceans,
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gathering cosmic elements
in the food they eat.
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And as they've done
for hundreds of millions of years…
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every new generation
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recycles this same stardust…
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to produce the next.
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-[fire roaring]
-[majestic music playing]
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Born in The Big Bang…
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[whooshing]
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…and forged in the hearts of stars…
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[whooshing, exploding]
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…90 chemical elements
have created everything.
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Endlessly recycled and reconfigured
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throughout the entire history
of the universe.
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[whooshing]
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And now…
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using the same elements,
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each new turtle begins a life cycle…
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-[zapping]
-[majestic music crescendos]
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…that mirrors the lives of the stars.
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[dramatic music playing]
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[calm music playing]
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[bird squawking]
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[Freeman]
On Australia's Great Barrier Reef…
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[squawking continues]
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…something magical has happened.
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[calm music continues]
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After 50 days beneath the sand,
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chemical elements
from across the cosmos have created life.
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Combining to form the next generation
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of green sea turtles.
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[egg rustling]
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[calm music continues]
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[egg cracking]
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The eggs have now exhausted their supply
of life-giving elements.
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[calm music continues]
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And today, the baby turtles
will take their first taste of air.
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And as her brothers and sisters
scramble to make it to the water…
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a little female…
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is last to be born.
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In order to grow to adulthood,
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she will need to harvest chemical elements
from across the ocean.
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It's a dangerous journey…
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[ominous music playing]
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…with treachery at every turn.
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[bird squawking]
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But for the baby turtles,
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the call of the ocean is irresistible.
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[birds squawking loudly]
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[ominous music continues]
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From a nest of 100,
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sometimes only one will survive.
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Sometimes none.
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[birds continue squawking]
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[suspenseful music playing]
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But despite the risk,
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the little female knows
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she must make it to the water.
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[birds squawking]
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[suspenseful music continues]
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[birds continue squawking]
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[suspenseful music continues]
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She spots an opening…
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and takes her chance.
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[pensive music playing]
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Today…
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she's a lucky one.
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The hatchling won't stop swimming
until she has left the reef far behind.
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[pensive music continues]
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Safely past the predators
that gather in the shallow coastal waters,
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she'll disappear into the great void
of the open ocean…
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to spend her childhood feeding on atoms.
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[whooshing, zapping]
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Atoms whose origins go back through
the entire life of the cosmos.
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[energetic rock music playing]
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[whooshing]
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To the time our universe
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00:09:30,640 --> 00:09:32,440
was in its infancy.
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[pulsing]
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[whooshing]
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00:09:48,000 --> 00:09:53,080
Expanding from nothing
to everything in an instant.
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Our universe was born in The Big Bang.
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[calm music playing]
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At first,
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it was nothing but a hot, dense fog.
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[wind howling]
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But as it continued to expand…
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the fog began to cool.
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And on the tiniest scale imaginable…
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[zapping]
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…something astounding began to occur.
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[pulsing]
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[uplifting music playing]
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The first atoms condensed out of the fog.
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[zapping]
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Atoms of hydrogen.
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[high-pitched squeaking]
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The very first element in the universe.
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[uplifting music continues]
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00:11:06,640 --> 00:11:07,800
And in the ocean,
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juvenile turtles are hunting it down.
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As they emerge from the blue
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to forage in the shallow waters
of the reef.
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This is Stella.
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One of the lucky ones
that made it off the beach
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00:11:31,280 --> 00:11:32,520
and into the ocean.
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[pensive music playing]
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She's already more than 2,000 times
her hatching weight
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and growing fast.
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Feeding on creatures she's found drifting
in the open ocean,
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she's harvested one element
more than any other.
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[majestic music playing]
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Hydrogen.
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It makes up more than half
of all the atoms in the food she eats.
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00:12:20,800 --> 00:12:24,480
And is the most abundant element
in all living things.
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From fish
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to invertebrates.
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Anemones and coral.
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Hydrogen atoms formed
at the dawn of the universe
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have been passed on from star to planet,
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planet to animal…
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00:13:08,320 --> 00:13:11,280
and from prey to predator.
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00:13:13,320 --> 00:13:14,560
[Stella exhales sharply]
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00:13:22,080 --> 00:13:23,480
Which means, for Stella,
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00:13:24,280 --> 00:13:27,000
the waters around the reef
are full of danger.
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00:13:28,000 --> 00:13:30,800
[suspenseful music playing]
138
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Tiger sharks, hungry for the same atoms,
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hunt sea turtles
throughout their adult lives.
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Stella's main defense is her trusty armor.
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Its bone toughened
with calcium and phosphorus.
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[suspenseful music continues]
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00:14:02,320 --> 00:14:05,320
Elements that date back
to another pivotal moment…
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00:14:09,400 --> 00:14:11,280
in the life of our universe.
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00:14:12,600 --> 00:14:14,800
[ethereal music playing]
146
00:14:21,920 --> 00:14:25,680
For the first 300 million years
after The Big Bang…
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00:14:28,080 --> 00:14:31,000
there are no planets and no stars.
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00:14:34,080 --> 00:14:36,600
The dark ages of the universe.
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00:14:37,200 --> 00:14:39,680
[ominous music playing]
150
00:14:42,360 --> 00:14:44,120
Concealed in the gloom,
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00:14:44,640 --> 00:14:48,600
vast tendrils
of hydrogen gas crisscross the cosmos.
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00:14:53,280 --> 00:14:55,560
And then, incredibly,
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00:14:56,200 --> 00:14:58,680
as they were drawn together by gravity…
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00:14:58,760 --> 00:15:00,600
[roaring]
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00:15:02,400 --> 00:15:04,520
…the first stars were born.
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00:15:05,040 --> 00:15:06,480
[zapping]
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00:15:11,120 --> 00:15:13,000
This is the cosmic dawn.
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00:15:13,080 --> 00:15:14,880
[ethereal music playing]
159
00:15:16,720 --> 00:15:20,880
The moment the lights came on.
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[buzzing]
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00:15:24,840 --> 00:15:26,640
[crackling]
162
00:15:28,000 --> 00:15:30,680
And deep within those first stars…
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00:15:34,880 --> 00:15:37,080
a remarkable process began.
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00:15:37,160 --> 00:15:39,480
[ethereal music continues]
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00:15:40,400 --> 00:15:42,720
[pulsing]
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00:15:42,800 --> 00:15:46,080
Temperatures and pressures
were so extreme…
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00:15:46,760 --> 00:15:48,000
[whooshing]
168
00:15:48,080 --> 00:15:50,360
…that new elements were created.
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00:15:52,520 --> 00:15:56,400
Atoms of hydrogen
were forced together to make helium.
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00:15:58,800 --> 00:16:01,880
As they fused, energy was released.
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00:16:01,960 --> 00:16:03,120
[zapping]
172
00:16:04,520 --> 00:16:09,200
Creating a chain reaction that produced
increasingly heavier elements.
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00:16:09,280 --> 00:16:11,080
[pulsing]
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00:16:12,320 --> 00:16:15,640
Including those essential for life.
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[zapping]
176
00:16:17,640 --> 00:16:21,360
Three helium atoms combined
to make carbon.
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00:16:21,440 --> 00:16:24,760
[dramatic music playing]
178
00:16:26,800 --> 00:16:29,480
The element on which all life is based.
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00:16:31,760 --> 00:16:34,560
Carbon and helium made oxygen.
180
00:16:36,120 --> 00:16:37,400
The air we breathe.
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00:16:37,480 --> 00:16:39,600
[intriguing music playing]
182
00:16:39,680 --> 00:16:42,880
Oxygen atoms combined to make phosphorus.
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00:16:44,920 --> 00:16:47,160
Then silicon and calcium.
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00:16:48,160 --> 00:16:49,240
[zapping]
185
00:16:50,200 --> 00:16:52,800
The elements
that make up every living thing
186
00:16:54,320 --> 00:16:58,800
were created in the hearts
of the very first stars.
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00:16:59,560 --> 00:17:02,000
[dramatic music playing]
188
00:17:05,400 --> 00:17:07,680
[penguins chirping]
189
00:17:13,720 --> 00:17:15,000
[elephant huffing]
190
00:17:25,160 --> 00:17:26,600
[dramatic music crescendos]
191
00:17:31,000 --> 00:17:31,880
For Stella,
192
00:17:33,160 --> 00:17:35,040
some elements are so important…
193
00:17:35,120 --> 00:17:37,280
[pensive music playing]
194
00:17:38,600 --> 00:17:41,080
…she'll travel great distances
to find them.
195
00:17:51,600 --> 00:17:56,000
The warm, shallow waters
between Australia and Papua New Guinea
196
00:17:57,360 --> 00:17:59,800
are a paradise of vibrant seagrass.
197
00:18:01,280 --> 00:18:04,120
[intriguing music playing]
198
00:18:04,200 --> 00:18:06,680
The prairies of the ocean.
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00:18:16,120 --> 00:18:21,960
Stella has traveled all the way here
to access their magic ingredients.
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[whooshing]
201
00:18:32,560 --> 00:18:34,000
As it grows,
202
00:18:34,080 --> 00:18:37,200
seagrass absorbs elements from outer space
203
00:18:37,920 --> 00:18:40,680
that have found their way
to the ocean floor.
204
00:18:43,880 --> 00:18:48,040
Burgeoning fronds
rich in calcium and phosphorus
205
00:18:49,760 --> 00:18:53,280
provide Stella
with precisely the minerals she needs
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00:18:55,080 --> 00:18:58,320
to build and sustain her protective shell.
207
00:18:58,400 --> 00:19:00,920
[intriguing music continues]
208
00:19:01,880 --> 00:19:06,000
Hardening her armor for the trials ahead.
209
00:19:14,400 --> 00:19:16,960
Stella will spend her adolescent years
210
00:19:17,680 --> 00:19:19,200
searching the ocean
211
00:19:20,920 --> 00:19:24,240
for atoms born in the stars.
212
00:19:24,880 --> 00:19:27,880
[intriguing music swells]
213
00:19:33,240 --> 00:19:35,080
Her journey toward maturity…
214
00:19:37,320 --> 00:19:40,800
paralleled in the story of our universe.
215
00:19:42,800 --> 00:19:45,600
[whooshing]
216
00:19:45,680 --> 00:19:48,920
Because three billion years
after The Big Bang…
217
00:19:51,960 --> 00:19:53,800
[ethereal music playing]
218
00:19:53,880 --> 00:19:56,680
…the universe was also coming of age.
219
00:20:02,640 --> 00:20:08,440
It was entering an incredibly active phase
of star formation.
220
00:20:10,560 --> 00:20:12,120
[pulsing]
221
00:20:12,200 --> 00:20:13,240
As they grew,
222
00:20:13,960 --> 00:20:17,280
stars were pulled together
into vast galaxies.
223
00:20:20,080 --> 00:20:21,800
Like our Milky Way.
224
00:20:21,880 --> 00:20:24,920
[dramatic music playing]
225
00:20:25,000 --> 00:20:26,880
And within those galaxies,
226
00:20:28,160 --> 00:20:30,840
the chemical elements each star produced…
227
00:20:30,920 --> 00:20:33,160
[whooshing]
228
00:20:34,520 --> 00:20:40,960
…were transformed into planets and moons.
229
00:20:46,640 --> 00:20:48,880
[dramatic music continues]
230
00:20:49,920 --> 00:20:51,480
After billions of years,
231
00:20:53,320 --> 00:20:58,880
chemical elements have matured
into the Earth we know today.
232
00:21:23,080 --> 00:21:25,800
Stella is now fully grown herself.
233
00:21:25,880 --> 00:21:29,080
[ethereal music playing]
234
00:21:29,880 --> 00:21:31,240
Over a meter long,
235
00:21:32,280 --> 00:21:35,600
she has a thick shell
covered in green algae.
236
00:21:39,240 --> 00:21:42,400
Ideal camouflage for cruising coral reefs.
237
00:21:46,600 --> 00:21:49,120
She is now at one with the ocean.
238
00:21:55,800 --> 00:21:57,440
Atoms from the stars
239
00:21:59,320 --> 00:22:02,600
perfectly adapted to life at sea.
240
00:22:03,080 --> 00:22:05,680
[ethereal music continues]
241
00:22:11,000 --> 00:22:13,120
Just one example of life on Earth…
242
00:22:15,280 --> 00:22:18,320
exquisitely shaped from the cosmos.
243
00:22:35,560 --> 00:22:39,000
Stella is now ready
for the next stage of her life.
244
00:22:39,080 --> 00:22:41,480
[ethereal music continues]
245
00:22:43,680 --> 00:22:47,000
Because she's about
to become a mother herself.
246
00:22:50,200 --> 00:22:51,320
Inside her body…
247
00:22:53,960 --> 00:22:56,480
she's carrying a clutch of 100 eggs.
248
00:22:58,280 --> 00:23:01,080
The first of many
she'll have over her lifetime.
249
00:23:03,680 --> 00:23:07,880
Her own precious cargo of stardust.
250
00:23:15,760 --> 00:23:17,120
All across the reef,
251
00:23:18,360 --> 00:23:20,720
atoms are being assembled into new life.
252
00:23:25,480 --> 00:23:30,160
Creating one of the richest ecosystems
on Earth.
253
00:23:35,920 --> 00:23:38,000
But our planet…
254
00:23:38,080 --> 00:23:39,960
[whooshing]
255
00:23:41,320 --> 00:23:42,400
…is an outlier.
256
00:23:44,960 --> 00:23:47,120
In the rest of the solar system,
257
00:23:47,200 --> 00:23:49,160
the very same elements
258
00:23:49,240 --> 00:23:54,000
have created worlds
far less suited to life.
259
00:23:54,080 --> 00:23:56,960
[whooshing]
260
00:23:57,040 --> 00:23:58,400
[eerie music playing]
261
00:23:59,920 --> 00:24:01,320
Closest to the sun,
262
00:24:02,080 --> 00:24:05,000
Mercury is a planet rich in carbon.
263
00:24:05,720 --> 00:24:07,800
[fizzling]
264
00:24:07,880 --> 00:24:09,680
But rather than creating life,
265
00:24:11,560 --> 00:24:13,800
the carbon is baked into its crust.
266
00:24:16,160 --> 00:24:19,920
On a world scorched by starlight.
267
00:24:20,520 --> 00:24:22,040
[whooshing]
268
00:24:22,520 --> 00:24:26,440
While in the farthest reaches
of the solar system,
269
00:24:26,520 --> 00:24:28,560
Neptune's freezing temperatures
270
00:24:29,480 --> 00:24:33,520
cause carbon and hydrogen
to form clouds of methane.
271
00:24:33,600 --> 00:24:34,920
[wind gusting]
272
00:24:36,680 --> 00:24:40,880
The suffocating gas
that gives it its brilliant blue.
273
00:24:42,120 --> 00:24:45,680
[whooshing]
274
00:24:46,640 --> 00:24:47,960
And even on Mars,
275
00:24:49,160 --> 00:24:51,960
a planet with all the same ingredients
as Earth…
276
00:24:54,320 --> 00:24:56,880
the lack of an oxygen-rich atmosphere
277
00:24:57,520 --> 00:25:00,880
means complex life couldn't survive here.
278
00:25:02,840 --> 00:25:05,200
[eerie music continues]
279
00:25:07,800 --> 00:25:12,080
Only on Earth are conditions just right.
280
00:25:18,320 --> 00:25:19,320
But even here,
281
00:25:20,120 --> 00:25:22,280
competition for elements is fierce.
282
00:25:24,200 --> 00:25:25,040
And danger…
283
00:25:25,120 --> 00:25:27,480
[ominous music playing]
284
00:25:27,560 --> 00:25:29,040
…is never far away.
285
00:25:44,880 --> 00:25:48,400
Luckily, Stella has become
an expert at hide-and-seek.
286
00:25:48,480 --> 00:25:50,880
[ominous music continues]
287
00:26:05,560 --> 00:26:07,800
[ominous music intensifies]
288
00:26:25,000 --> 00:26:27,280
[calm music playing]
289
00:26:29,920 --> 00:26:31,400
Safe for now…
290
00:26:34,320 --> 00:26:37,320
Stella faces the biggest challenge
of her life.
291
00:26:39,520 --> 00:26:42,280
To return to the Great Barrier Reef
292
00:26:43,920 --> 00:26:45,600
and the island of her birth…
293
00:26:49,480 --> 00:26:51,880
to lay her own eggs in the sand.
294
00:26:58,880 --> 00:27:01,440
But a lifetime spent wandering the ocean
295
00:27:02,200 --> 00:27:05,600
means she's now 2,000 kilometers away.
296
00:27:05,680 --> 00:27:08,040
[calm music continues]
297
00:27:09,840 --> 00:27:11,520
How Stella navigates home
298
00:27:12,160 --> 00:27:14,760
is one of the wonders
of the natural world.
299
00:27:19,880 --> 00:27:21,320
[humming]
300
00:27:21,400 --> 00:27:22,760
Deep within the Earth,
301
00:27:23,600 --> 00:27:26,600
our planet's core generates
a magnetic field…
302
00:27:28,840 --> 00:27:33,880
which gives every place on its surface
a unique magnetic signature.
303
00:27:34,880 --> 00:27:36,600
[intriguing music playing]
304
00:27:37,560 --> 00:27:39,120
When she hatched,
305
00:27:39,200 --> 00:27:43,520
her island's signature
was imprinted in Stella's brain.
306
00:27:46,200 --> 00:27:48,200
And to find her way back,
307
00:27:48,280 --> 00:27:51,600
she'll rely on
yet another chemical element.
308
00:27:53,760 --> 00:27:56,880
One that connects her
to the planet's core.
309
00:28:00,400 --> 00:28:05,080
An element that's only created
when stars die.
310
00:28:08,400 --> 00:28:10,600
[ethereal music playing]
311
00:28:10,680 --> 00:28:12,720
In a nearby part of the galaxy,
312
00:28:13,720 --> 00:28:15,680
two and a half million years ago,
313
00:28:16,720 --> 00:28:20,520
a dramatic change took place
in the core of a giant star.
314
00:28:21,240 --> 00:28:23,480
[hissing]
315
00:28:25,280 --> 00:28:29,360
For all its life,
it had been powered by nuclear fusion.
316
00:28:30,360 --> 00:28:31,720
[pulsing]
317
00:28:35,880 --> 00:28:37,200
The energy released…
318
00:28:37,280 --> 00:28:38,960
[zapping]
319
00:28:39,040 --> 00:28:41,440
…creating heavier and heavier elements.
320
00:28:42,320 --> 00:28:44,480
[whooshing]
321
00:28:45,200 --> 00:28:48,120
Until the core became so hot,
322
00:28:48,640 --> 00:28:49,880
it started creating…
323
00:28:49,960 --> 00:28:51,560
[whooshing, zapping]
324
00:28:51,640 --> 00:28:52,480
…iron.
325
00:28:55,360 --> 00:28:58,200
Which caused a fundamental change
to take place.
326
00:28:59,960 --> 00:29:02,280
[whooshing, zapping]
327
00:29:03,080 --> 00:29:06,360
Because making iron
doesn't release energy.
328
00:29:07,880 --> 00:29:09,160
It consumes it.
329
00:29:10,080 --> 00:29:11,680
[cracking]
330
00:29:15,880 --> 00:29:18,360
As more and more
of the metal was produced,
331
00:29:19,240 --> 00:29:22,760
it spread through the core like a disease.
332
00:29:27,160 --> 00:29:29,160
Feeding off the star's heat.
333
00:29:29,240 --> 00:29:31,680
[cracking rapidly]
334
00:29:33,880 --> 00:29:34,880
Throttling it.
335
00:29:39,240 --> 00:29:41,400
[ethereal music continues]
336
00:29:41,480 --> 00:29:43,800
[cracking continues]
337
00:29:46,280 --> 00:29:48,560
With no heat source to hold it up.
338
00:29:49,400 --> 00:29:51,760
[gurgling]
339
00:29:52,840 --> 00:29:54,400
From this moment onward…
340
00:29:55,680 --> 00:29:57,400
[ethereal tinkling]
341
00:29:57,480 --> 00:29:59,680
…the star was doomed.
342
00:29:59,760 --> 00:30:02,160
[rumbling]
343
00:30:03,240 --> 00:30:05,680
[booming, ringing]
344
00:30:11,600 --> 00:30:16,200
The resulting explosion shone
with the brightness of 10 billion suns.
345
00:30:16,280 --> 00:30:20,000
[whooshing, zapping]
346
00:30:20,080 --> 00:30:21,920
[rumbling]
347
00:30:22,000 --> 00:30:27,080
A supernova which propelled
iron-rich dust across the galaxy.
348
00:30:27,160 --> 00:30:30,000
[wind whipping]
349
00:30:30,080 --> 00:30:32,640
[ethereal music playing]
350
00:30:35,120 --> 00:30:38,120
All the way to our planet.
351
00:30:43,160 --> 00:30:44,280
And even now,
352
00:30:45,280 --> 00:30:50,280
100 tons of stardust enters
Earth's atmosphere every day.
353
00:30:53,080 --> 00:30:56,800
Some left over
from the formation of the solar system.
354
00:30:56,880 --> 00:30:59,040
[ethereal tinkling]
355
00:31:00,600 --> 00:31:04,480
Some blown here from distant supernovas.
356
00:31:08,400 --> 00:31:13,600
A direct link
between our planet and the stars.
357
00:31:14,360 --> 00:31:16,680
[ethereal music continues]
358
00:31:19,680 --> 00:31:21,960
And it's the iron in this dust
359
00:31:22,520 --> 00:31:25,400
that allows Stella to find her way.
360
00:31:25,480 --> 00:31:28,400
[ethereal tinkling]
361
00:31:33,520 --> 00:31:35,200
Because deep in her brain…
362
00:31:35,280 --> 00:31:36,960
[whooshing]
363
00:31:37,040 --> 00:31:38,200
[pulsing]
364
00:31:38,280 --> 00:31:43,600
…specialized cells are thought
to contain crystals of magnetite.
365
00:31:44,520 --> 00:31:48,760
An iron-rich mineral that aligns itself
to the Earth's magnetic field.
366
00:31:48,840 --> 00:31:51,680
[intriguing music playing]
367
00:31:52,760 --> 00:31:53,680
A compass,
368
00:31:55,560 --> 00:31:57,680
pointing her in the right direction.
369
00:32:05,440 --> 00:32:11,680
Allowing Stella to find
the unique magnetic fingerprint of home.
370
00:32:13,720 --> 00:32:16,040
[intriguing music continues]
371
00:32:19,480 --> 00:32:22,680
And so an element forged in a supernova…
372
00:32:22,760 --> 00:32:25,280
[ethereal music playing]
373
00:32:30,360 --> 00:32:34,280
…will now guide her across kilometers
of featureless ocean.
374
00:32:48,600 --> 00:32:49,920
Back to the island…
375
00:32:53,800 --> 00:32:55,480
on which she was born.
376
00:33:08,120 --> 00:33:12,040
But there are other creatures
with magnetic homing abilities.
377
00:33:12,560 --> 00:33:14,600
[ominous music playing]
378
00:33:14,680 --> 00:33:16,480
The tiger sharks have it too.
379
00:33:19,600 --> 00:33:22,280
And it's leading them back
to the same island.
380
00:33:26,560 --> 00:33:28,920
Because for a few months every year,
381
00:33:29,000 --> 00:33:32,600
thousands of female turtles come here
to lay their eggs.
382
00:33:34,600 --> 00:33:37,880
It's the largest gathering
of green sea turtles
383
00:33:37,960 --> 00:33:39,960
anywhere on the planet.
384
00:33:41,640 --> 00:33:43,400
[ominous music continues]
385
00:33:45,600 --> 00:33:47,320
And as they come to shore,
386
00:33:49,080 --> 00:33:50,320
the feeding begins.
387
00:33:50,400 --> 00:33:52,080
[ominous music crescendos]
388
00:33:57,280 --> 00:34:00,120
[tense music playing]
389
00:34:03,800 --> 00:34:06,160
Stella must wait for the right moment…
390
00:34:08,840 --> 00:34:10,040
to find an opening…
391
00:34:12,160 --> 00:34:14,080
and avoid the onslaught.
392
00:34:14,600 --> 00:34:17,080
[tense music continues]
393
00:34:21,800 --> 00:34:24,480
[calm music playing]
394
00:34:27,680 --> 00:34:30,920
[birds squawking]
395
00:34:32,080 --> 00:34:33,800
When the danger has passed…
396
00:34:37,440 --> 00:34:39,080
she finally swims ashore.
397
00:34:43,680 --> 00:34:46,400
[triumphant music playing]
398
00:34:52,280 --> 00:34:53,880
After an epic journey…
399
00:34:57,080 --> 00:34:59,240
Stella emerges onto the sand
400
00:35:00,840 --> 00:35:03,320
she last touched as a hatchling.
401
00:35:08,840 --> 00:35:11,920
[triumphant music continues]
402
00:35:28,040 --> 00:35:30,920
The elements she spent
a lifetime collecting…
403
00:35:36,600 --> 00:35:39,160
are now safely delivered into the sand.
404
00:35:45,240 --> 00:35:46,960
Stella's mission is complete,
405
00:35:47,520 --> 00:35:49,240
and she returns to the ocean…
406
00:35:52,880 --> 00:35:56,600
to begin gathering stardust once more.
407
00:36:00,480 --> 00:36:01,800
The cycle of her life
408
00:36:03,640 --> 00:36:06,520
mirroring the grandest cycle of all.
409
00:36:08,440 --> 00:36:11,920
The lives and deaths of the stars.
410
00:36:13,080 --> 00:36:15,480
[ethereal music playing]
411
00:36:22,480 --> 00:36:25,600
Because far away across the galaxy,
412
00:36:27,000 --> 00:36:29,680
the ashes of countless supernovas
413
00:36:29,760 --> 00:36:34,480
have come together to form a giant nebula.
414
00:36:34,560 --> 00:36:37,280
[ethereal tinkling]
415
00:36:41,280 --> 00:36:44,480
A cloud of stardust
tens of light-years across.
416
00:36:48,120 --> 00:36:52,600
And buried within it are places
where the next generation of stars
417
00:36:53,840 --> 00:36:55,280
are beginning to form.
418
00:36:55,360 --> 00:36:57,760
[ethereal music continues]
419
00:37:06,800 --> 00:37:08,400
Called proplyds.
420
00:37:10,400 --> 00:37:12,880
They're like vast cosmic eggs.
421
00:37:15,000 --> 00:37:17,680
Each one bigger than our solar system.
422
00:37:23,720 --> 00:37:26,640
Inside their shells of ionized gas,
423
00:37:28,560 --> 00:37:31,480
the force of gravity
is pulling stardust together.
424
00:37:33,080 --> 00:37:35,880
[whooshing]
425
00:37:38,880 --> 00:37:42,400
And the stardust inside Stella's eggs…
426
00:37:45,440 --> 00:37:47,560
is also beginning to take shape.
427
00:37:47,640 --> 00:37:50,040
[ethereal music continues]
428
00:37:51,720 --> 00:37:54,320
[heartbeat thumping]
429
00:37:56,200 --> 00:38:01,800
As the elements she collected
are being transformed…
430
00:38:08,280 --> 00:38:11,800
into something that's starting
to resemble a tiny creature.
431
00:38:18,240 --> 00:38:21,280
[dramatic music playing]
432
00:38:24,280 --> 00:38:25,640
And within the proplyd…
433
00:38:27,840 --> 00:38:30,240
gases like hydrogen and helium…
434
00:38:31,840 --> 00:38:33,040
[rumbling]
435
00:38:33,120 --> 00:38:35,680
…are feeding an embryonic star.
436
00:38:39,160 --> 00:38:42,000
[dramatic music continues]
437
00:38:44,880 --> 00:38:46,680
And what was once an embryo…
438
00:38:49,080 --> 00:38:51,080
is now a tiny turtle…
439
00:38:55,200 --> 00:38:58,880
with shell, flippers, and beak.
440
00:39:02,880 --> 00:39:04,680
Elements reimagined…
441
00:39:08,080 --> 00:39:10,280
for a life at sea.
442
00:39:10,360 --> 00:39:12,680
[heartbeat thumping]
443
00:39:15,160 --> 00:39:16,120
In the proplyd,
444
00:39:17,000 --> 00:39:20,200
the new star's development
is also nearing completion.
445
00:39:21,480 --> 00:39:24,800
Reborn from the ashes
of the previous generation,
446
00:39:26,120 --> 00:39:30,000
its light now reveals a family
of growing planets in orbit.
447
00:39:34,200 --> 00:39:35,320
New worlds.
448
00:39:36,240 --> 00:39:40,280
But perhaps, new possibilities for life.
449
00:39:41,680 --> 00:39:44,120
[dramatic music continues]
450
00:39:48,280 --> 00:39:49,920
And beneath the sand,
451
00:39:51,240 --> 00:39:52,760
the same stardust,
452
00:39:54,080 --> 00:39:58,800
passed down through countless generations
of stars and turtles…
453
00:40:00,880 --> 00:40:03,200
will start yet another journey.
454
00:40:07,000 --> 00:40:08,080
[egg cracking]
455
00:40:08,160 --> 00:40:09,560
Each new life
456
00:40:11,080 --> 00:40:15,400
directly connected
to the origin of the universe.
457
00:40:18,680 --> 00:40:20,760
[dramatic music crescendos]
458
00:40:20,840 --> 00:40:26,400
Each new story beginning
at the end of the last.
459
00:40:31,160 --> 00:40:33,920
-[thunder rumbling]
-[lightning zapping]
460
00:40:34,880 --> 00:40:38,880
And so,
the story of our universe continues…
461
00:40:38,960 --> 00:40:40,680
[ethereal tinkling]
462
00:40:40,760 --> 00:40:43,000
…with Earth's most precious resource…
463
00:40:43,080 --> 00:40:45,240
[ethereal music playing]
464
00:40:46,280 --> 00:40:47,120
…water.
465
00:40:48,920 --> 00:40:52,800
And a family of elephants
on a dangerous mission to find it.
466
00:40:54,320 --> 00:40:55,440
[elephant huffing]
467
00:40:57,000 --> 00:40:59,360
Their journey every bit as extraordinary…
468
00:40:59,440 --> 00:41:01,080
[lion growls]
469
00:41:01,680 --> 00:41:06,440
…as water's journey across the vastness
of space to our planet.
470
00:41:10,640 --> 00:41:13,840
But why is Earth the only world
in the solar system
471
00:41:14,840 --> 00:41:17,240
whose surface
is covered with liquid water?
472
00:41:18,600 --> 00:41:21,960
And why is it so essential for life?
473
00:41:22,680 --> 00:41:23,920
[elephant trumpets]
474
00:41:26,080 --> 00:41:29,680
[dramatic music playing]