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NEIL DEGRASSE TYSON:
We pulled the stars
from the skies...
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...and brought them
down to Earth.
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00:00:23,640 --> 00:00:26,408
But at what cost?
4
00:00:26,443 --> 00:00:29,578
When we turned on
all these lights...
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we lost something precious.
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The stars.
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¶ ¶
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¶ ¶
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(flames crackling)
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A long time ago,
in a world lit only by fire,
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our relationship with the stars
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00:02:40,310 --> 00:02:42,544
was far more...
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00:02:42,579 --> 00:02:44,046
personal.
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For thousands of generations,
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we watched the stars
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as if our lives depended on it.
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Because they did.
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We humans were not the biggest,
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the strongest, nor the fastest
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of all the animals
we competed against.
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But we did have
one thing going for us:
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our intelligence.
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One aspect of that was a genius
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for pattern recognition.
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Night after night,
we watched the stars.
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And over time,
our ancestors noticed
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that the motions of the stars
across the nights of the year
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foretold changes on Earth
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that threatened or enhanced
our chances for survival.
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In a time
when our imaginations
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were the only stage
where stories came to life,
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before there were movies or TVs
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or electronic devices
of any kind,
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every human culture
connected the dots
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to form their own pictures.
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These images became the
illustrations of a storybook
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that, on a deeper level,
was also a survival manual.
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The names and personalities
of the gods, heroes,
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farm animals
or familiar objects
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varied from culture to culture.
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But there was one particularly
gorgeous group of stars
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known to the ancient Greeks
and to us today
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as the Pleiades,
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a star cluster formed
about 100 million years ago.
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Each of them is some 40 times
brighter than our Sun.
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And Alcyone, the most luminous,
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outshines our Sun 1,000 times.
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For ages, the Pleiades
have been used as an eye test
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for people all over the world.
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If you could see
at least six of them,
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you were considered normal.
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If you saw more than seven,
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you were an ideal candidate
for a warrior or scout.
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Among the ancient Celts and
Druids of the British Isles,
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the Pleiades were believed to
have a haunting significance.
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On the night of the year
that they reach
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the highest point
in the sky at midnight,
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the spirits of the dead were
thought to wander the Earth.
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This is believed to be
the origin of the holiday
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00:04:47,270 --> 00:04:49,338
once known as Samhain,
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now called Halloween.
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All over the Earth,
our ancestors told
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wonderful stories to explain
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how the Pleiades came
to be in the sky.
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00:04:58,715 --> 00:05:01,049
For the Kiowa people
of North America,
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it happened something like this.
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(indistinct chatter)
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Long, long ago,
some young women
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snuck away from their campsite
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to dance freely
beneath the stars.
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¶ ¶
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(bear roaring)
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(women screaming)
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(roaring)
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(panting)
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Rock, save us!
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Rock, take pity on us!
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DEGRASSE TYSON:
The rock heard their cries
and grew taller.
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00:06:07,183 --> 00:06:11,520
Until it became what is today
known as the Devil's Tower.
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00:06:15,992 --> 00:06:20,262
The maidens were transformed
into the stars of the Pleiades,
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00:06:20,296 --> 00:06:23,899
which may be seen hanging
above the tower in midwinter.
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00:06:25,802 --> 00:06:28,103
The ancient Greeks
also saw those seven jewels
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as seven maidens,
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the seven daughters of Atlas,
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pursued not by bears, but by...
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00:06:36,579 --> 00:06:38,547
Orion the hunter,
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who spied them when he was
out walking one day.
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Orion became mad with desire.
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00:06:55,364 --> 00:06:56,364
(gasps)
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(maidens screaming)
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For seven years,
he chased them relentlessly.
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00:07:06,509 --> 00:07:08,844
Exhausted...
Zeus, help us.
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00:07:08,878 --> 00:07:11,346
they prayed to Zeus
for deliverance.
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00:07:13,516 --> 00:07:17,986
Zeus, the king of the gods,
felt sorry for them,
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00:07:18,020 --> 00:07:20,222
and transformed
those seven maidens
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into the Pleiades.
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00:07:31,067 --> 00:07:34,402
But the gods are,
if anything, capricious.
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00:07:34,437 --> 00:07:38,006
When Orion was killed
by the sting of a scorpion,
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Zeus placed him in the sky where
he could resume his pursuit
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of the seven gorgeous sisters.
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Our ancestors, they wove
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brilliantly imaginative stories.
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But they can bring us
no closer to the stars
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than our dreams.
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00:07:50,953 --> 00:07:53,722
It took yet another
few thousand years
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until three brilliant scientists
unlocked the secrets
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of the true lives of the stars.
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DEGRASSE TYSON:
In 1901,
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Harvard was a man's world.
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But an astronomer named
Edward Charles Pickering
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00:08:16,312 --> 00:08:17,979
broke that rule.
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Oh, Pickering's office
is just down the hallway.
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And that door over
there leads to the room
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where he keeps
his computers.
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We're supposed to call those
women "computers," but, uh,
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I've heard more than one fellow
refer to those gals
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as "Pickering's Harem."
(men laughing)
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DEGRASSE TYSON:
Pickering assembled
a team of women
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to map and classify
the types of stars.
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One of them provided the key
to our understanding
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of the substance of the stars.
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And another devised a way
for us to calculate
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the size of the universe.
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For some reason, you probably
never heard of either of them.
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00:09:09,565 --> 00:09:12,033
Wonder why.
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That's Annie Jump Cannon,
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the leader of the team.
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Before she was through,
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she catalogued a quarter
of a million stars.
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Number 11 is a B7.
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That's Alcyone in the Pleiades.
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DEGRASSE TYSON:
Cannon lost her hearing
during a bout of scarlet fever
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when she was a young woman.
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Number 12 is a B6.
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00:09:37,093 --> 00:09:39,928
DEGRASSE TYSON:
That's Henrietta Swan Leavitt.
She's also deaf.
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And she's the other
great scientist in the room.
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Leavitt discovered the law
that astronomers still use
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more than a century later
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to measure the distances
to the stars
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and the size
of the cosmos itself.
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00:09:55,311 --> 00:09:58,213
Annie Jump Cannon sent out
a Christmas card explaining
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what she and her sisters
were actually doing.
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00:10:01,317 --> 00:10:03,251
The light from a star
is allowed
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to fall through a prism placed
in the telescope, she wrote.
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00:10:06,789 --> 00:10:10,458
Thus magnified, the starlight
is split up into a band
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showing its component colors,
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the red rays going to one end
and the violet to the other.
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This is the spectrum
of the star.
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It shows the presence
of fine, dark lines.
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00:10:22,538 --> 00:10:24,673
By comparing them
with lines given
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by glowing substances
in the laboratory,
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we can determine that the same
elements familiar to us
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on the Earth also exist
in the outermost star.
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This is plate number
12358B.
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Number one at this plate
is a B-type star.
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Make that a B2.
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DEGRASSE TYSON:
It took Cannon decades
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to classify
the spectral character
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of hundreds of thousands
of stars
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according to the scheme
that she devised.
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Cannon discovered
that the stars fell
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into a continuous sequence
of seven broad categories
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according to their spectral
line patterns.
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Each was designated
by a letter.
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But the spectral lines of two
stars in the same letter class
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could differ in subtle ways,
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minute variations
that Cannon learned
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to recognize from memory.
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To distinguish these spectra
from one another,
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she assigned ten numerical
subcategories for each class.
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Annie Jump Cannon
organized the stars,
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but it would fall to another
scientist to decipher
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the hidden meaning in her work.
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(ship's horn blows thrice)
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In the England of 1923,
women were forbidden
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from pursuing
advanced degrees in science.
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But Cecelia Payne had attended
a lecture in London
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by the astronomer
Sir Arthur Eddington,
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the first scientist
to provide evidence
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00:12:06,876 --> 00:12:08,510
that Einstein's revolutionary
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00:12:08,544 --> 00:12:10,712
General Theory of Relativity
was correct.
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From that moment on,
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she knew that nothing
would deter her
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from pursing her big dreams.
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She resolved to emigrate
to America,
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where women had already
gained the freedom
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to study the stars.
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Her application was accepted
at Harvard.
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What she would discover there
would challenge
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one of the central beliefs
of astronomy.
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The resulting impact
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00:12:35,104 --> 00:12:38,440
would be the dawn
of modern astrophysics.
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DEGRASSE TYSON:
As the decades passed,
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00:12:45,781 --> 00:12:48,983
Annie Jump Cannon and her team
kept sifting the stars,
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checking each one's
spectral signature
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with a fleeting glance
and then dropping them
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into one of seven categories.
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They became hundreds
of thousands of dots
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00:12:58,360 --> 00:13:01,663
in a larger picture which
no one could yet understand.
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00:13:01,697 --> 00:13:06,568
Into this community of women
came one more.
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Well, hello there.
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You must be Miss Payne.
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We've been
waiting for you.
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Come on in.
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00:13:16,378 --> 00:13:19,047
DEGRASSE TYSON:
Cecilia Payne had never
experienced such kindness
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00:13:19,081 --> 00:13:21,616
in a scientific setting before.
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00:13:21,650 --> 00:13:24,285
This sisterhood
generously shared
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00:13:24,320 --> 00:13:26,387
the fruits of their labors
with her,
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00:13:26,422 --> 00:13:28,223
and she turned
their observations
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00:13:28,257 --> 00:13:31,793
into a radical new
understanding of the stars.
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00:13:31,827 --> 00:13:34,929
The two women became
great friends.
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00:13:34,964 --> 00:13:36,664
Cannon taught Payne everything
she had learned
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00:13:36,699 --> 00:13:38,199
about stellar spectra.
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00:13:38,234 --> 00:13:40,001
And Payne began to analyze
Cannon's data
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00:13:40,035 --> 00:13:43,738
to see if she could determine
the actual chemical composition
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00:13:43,772 --> 00:13:45,974
and physical state of the stars.
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00:13:46,008 --> 00:13:48,309
She brought to this work
her expertise
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00:13:48,344 --> 00:13:50,178
in theoretical
and atomic physics.
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00:13:53,015 --> 00:13:55,850
The most prominent features
in the spectra of stars
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00:13:55,885 --> 00:13:57,585
showed the presence
of heavy elements
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00:13:57,620 --> 00:14:01,556
such as calcium... and iron,
222
00:14:01,590 --> 00:14:04,526
which are among the most
abundant elements in the Earth.
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00:14:04,560 --> 00:14:06,528
So astronomers
naturally concluded
224
00:14:06,562 --> 00:14:08,396
that the stars were made
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00:14:08,430 --> 00:14:10,365
of the same elements
as the Earth
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00:14:10,399 --> 00:14:12,534
and in roughly
the same proportions.
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00:14:12,568 --> 00:14:17,438
In 1924, Henry Norris Russell
was the dean
228
00:14:17,473 --> 00:14:20,742
of American astronomers,
having made major contributions
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00:14:20,776 --> 00:14:23,111
to our understanding
of the stars.
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00:14:23,145 --> 00:14:25,880
RUSSELL:
40 to 45 of the
chemical elements
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00:14:25,915 --> 00:14:27,749
that we have here on Earth
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00:14:27,783 --> 00:14:30,552
are also present
in the spectrum of the Sun.
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00:14:30,586 --> 00:14:34,088
So we can assume
that the composition of the Sun
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00:14:34,123 --> 00:14:36,958
resembles that of the Earth.
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00:14:36,992 --> 00:14:40,461
If one were to heat the crust
of the Earth to incandescence,
236
00:14:40,496 --> 00:14:44,065
its spectrum would resemble
that of the Sun.
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00:14:58,647 --> 00:15:02,584
Annie, I think I now
understand what it all means.
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All your years of work.
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00:15:04,520 --> 00:15:05,753
Tell me.
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00:15:05,788 --> 00:15:07,388
I've calculated
what the spectra
241
00:15:07,423 --> 00:15:09,457
should look like
across a wide range
242
00:15:09,491 --> 00:15:11,125
of temperatures,
and they match
243
00:15:11,160 --> 00:15:13,962
your system
of classification perfectly.
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00:15:13,996 --> 00:15:18,166
The spectrum of any star
tells you exactly how hot it is.
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00:15:18,200 --> 00:15:24,172
Your "O-B-A-F-G-K-M" is really
a temperature scale of the stars
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00:15:24,206 --> 00:15:26,708
from the hottest to the coldest.
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00:15:28,877 --> 00:15:31,679
Here's the headline, Annie:
Thanks to your work,
248
00:15:31,714 --> 00:15:33,748
I've discovered that the stars
are made almost entirely
249
00:15:33,782 --> 00:15:35,416
of hydrogen and helium.
250
00:15:35,451 --> 00:15:38,519
There's a million times more
hydrogen and helium
251
00:15:38,554 --> 00:15:40,688
than the metals
in the stars.
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00:15:40,723 --> 00:15:43,358
I know, it sounds daft.
253
00:15:43,392 --> 00:15:45,426
Are you certain?
254
00:15:45,461 --> 00:15:50,164
Has anyone else checked
your calculations?
255
00:15:50,199 --> 00:15:52,767
Not yet,
but it's all in my thesis,
256
00:15:52,801 --> 00:15:55,236
which is already on its way
to Professor Russell.
257
00:16:06,849 --> 00:16:08,883
Poor woman.
258
00:16:08,917 --> 00:16:12,153
DEGRASSE TYSON:
Russell felt sorry
for Cecilia Payne.
259
00:16:12,187 --> 00:16:15,690
Her thesis appeared to him
to be fundamentally flawed.
260
00:16:23,265 --> 00:16:26,701
RUSSELL:
It is clearly impossible
that hydrogen should be
261
00:16:26,735 --> 00:16:29,404
a million times more abundant
than the metals.
262
00:16:33,609 --> 00:16:37,378
DEGRASSE TYSON:
Her carefully gathered evidence
flew in the face
263
00:16:37,413 --> 00:16:40,048
of conventional
scientific wisdom.
264
00:16:40,082 --> 00:16:42,016
"How could I be right,"
she asked,
265
00:16:42,051 --> 00:16:44,252
"if that must mean
266
00:16:44,286 --> 00:16:47,255
that such a distinguished
scientist was wrong?"
267
00:16:48,957 --> 00:16:51,993
Despite her confidence
in the quality of her research,
268
00:16:52,027 --> 00:16:55,096
she caved and added a sentence
to her thesis
269
00:16:55,130 --> 00:16:58,099
that undermined
its greatest insight.
270
00:17:03,639 --> 00:17:05,073
It would be four years
271
00:17:05,107 --> 00:17:07,842
before Russell realized
that Payne was right.
272
00:17:07,876 --> 00:17:11,012
To his credit,
as soon as he did,
273
00:17:11,046 --> 00:17:13,381
he acknowledged
that it was her discovery.
274
00:17:16,819 --> 00:17:20,621
Payne's "Stellar Atmospheres"
is widely regarded
275
00:17:20,656 --> 00:17:22,757
as the most brilliant
PhD thesis
276
00:17:22,791 --> 00:17:24,592
ever written in astronomy.
277
00:17:24,626 --> 00:17:28,963
It became the standard text
in its field.
278
00:17:28,997 --> 00:17:32,700
PAYNE:
I was to blame for not having
pressed my point.
279
00:17:32,735 --> 00:17:37,572
I had given in to authority
when I believed I was right.
280
00:17:37,606 --> 00:17:39,640
If you are sure of your facts,
281
00:17:39,675 --> 00:17:42,110
you should defend
your position.
282
00:17:43,512 --> 00:17:45,580
DEGRASSE TYSON:
The words of the powerful
283
00:17:45,614 --> 00:17:48,416
may prevail in other spheres
of human experience,
284
00:17:48,450 --> 00:17:52,420
but in science, the only thing
that counts is the evidence
285
00:17:52,454 --> 00:17:54,922
and the logic
of the argument itself.
286
00:17:54,957 --> 00:17:58,326
Cecilia Payne's interpretation
of Annie Jump Cannon's sequence
287
00:17:58,360 --> 00:18:01,095
of stellar spectra
made it possible for us
288
00:18:01,130 --> 00:18:03,331
to read the life stories
of the stars
289
00:18:03,365 --> 00:18:07,335
and to trace the story of life
itself back to its beginnings
290
00:18:07,369 --> 00:18:10,371
in their fiery deaths.
291
00:18:16,295 --> 00:18:19,063
DEGRASSE TYSON:
There are many kinds of stars.
292
00:18:19,098 --> 00:18:21,632
Some are bright like the Sun.
293
00:18:21,667 --> 00:18:23,768
Some are dim.
294
00:18:23,802 --> 00:18:25,903
The greatest stars
are ten million times larger
295
00:18:25,938 --> 00:18:28,139
than the smallest ones.
296
00:18:28,173 --> 00:18:30,741
Some stars are old
beyond imagining,
297
00:18:30,776 --> 00:18:33,945
more than ten billion years
of age.
298
00:18:33,979 --> 00:18:36,314
Others are being born
right now.
299
00:18:40,052 --> 00:18:43,020
When atoms fuse
in the hearts of stars,
300
00:18:43,055 --> 00:18:44,322
they make starlight.
301
00:18:44,356 --> 00:18:46,257
Stars are born in litters,
302
00:18:46,291 --> 00:18:49,927
formed from the gas and dust
of interstellar clouds.
303
00:18:49,962 --> 00:18:52,864
The mass of the individual
stars in a litter
304
00:18:52,898 --> 00:18:55,199
can range from the runts--
not much larger
305
00:18:55,234 --> 00:18:57,268
than the largest planets--
306
00:18:57,302 --> 00:19:00,071
to the supergiant stars
that dwarf the Sun.
307
00:19:06,245 --> 00:19:10,148
The stars in the nebula below
Orion's Belt are newborns,
308
00:19:10,182 --> 00:19:11,883
around five million years old,
309
00:19:11,917 --> 00:19:15,119
and still swaddled
in the gas and dust
310
00:19:15,154 --> 00:19:17,321
that gave birth to them.
311
00:19:17,356 --> 00:19:20,491
The stars in the Pleiades
are already toddlers,
312
00:19:20,526 --> 00:19:22,393
about 100 million years old.
313
00:19:22,427 --> 00:19:24,529
They've shed their blankets
of gas and dust,
314
00:19:24,563 --> 00:19:26,464
but they're still bound
together
315
00:19:26,498 --> 00:19:28,399
by their mutual gravity.
316
00:19:28,433 --> 00:19:30,334
Another few hundred
million years,
317
00:19:30,369 --> 00:19:32,970
and they'll drift apart
and go their separate ways,
318
00:19:33,005 --> 00:19:35,506
never to meet again.
319
00:19:35,541 --> 00:19:39,143
Most of the stars of the
Big Dipper are adolescents,
320
00:19:39,178 --> 00:19:41,712
roughly half a billion
years old.
321
00:19:41,747 --> 00:19:44,315
They've already drifted apart
from their birth cluster,
322
00:19:44,349 --> 00:19:47,385
although we can still trace
their common ancestry.
323
00:19:47,419 --> 00:19:50,821
Eventually, they'll spread out
around the Milky Way galaxy.
324
00:19:50,856 --> 00:19:53,691
But most of the familiar
constellations
325
00:19:53,725 --> 00:19:57,061
are a mix of entirely
unrelated stars,
326
00:19:57,095 --> 00:19:58,863
some faint and nearby,
327
00:19:58,897 --> 00:20:02,033
others bright and far away.
328
00:20:04,570 --> 00:20:06,103
Our own Sun?
329
00:20:06,138 --> 00:20:08,105
From the distance
of even a few light-years,
330
00:20:08,140 --> 00:20:11,542
it's hard to find
amidst the other stars.
331
00:20:11,577 --> 00:20:13,578
It's that one.
332
00:20:15,214 --> 00:20:16,714
Our Sun is middle-aged
333
00:20:16,748 --> 00:20:18,683
and a long way
from where it was born.
334
00:20:18,717 --> 00:20:20,384
Its sister stars,
335
00:20:20,419 --> 00:20:22,186
hatched from the same
interstellar cloud,
336
00:20:22,221 --> 00:20:25,056
are dispersed
throughout the galaxy.
337
00:20:25,090 --> 00:20:27,725
Many of them have
their own planets.
338
00:20:27,759 --> 00:20:29,627
Perhaps some of them nurture
339
00:20:29,661 --> 00:20:32,730
the evolution of life
and intelligence.
340
00:20:32,764 --> 00:20:34,865
Most of the stars
in our night sky
341
00:20:34,900 --> 00:20:38,536
actually orbit around one
or more stellar companions.
342
00:20:38,570 --> 00:20:40,071
With the naked eye,
343
00:20:40,105 --> 00:20:41,639
we usually can't see
the fainter members
344
00:20:41,673 --> 00:20:43,908
in such double
and multiple star systems.
345
00:20:46,645 --> 00:20:48,546
On a world with three suns,
346
00:20:48,580 --> 00:20:50,481
the nights would be rare
347
00:20:50,515 --> 00:20:54,151
and the days might alternate
between red and blue.
348
00:21:00,659 --> 00:21:03,394
It is the destiny
of stars to collapse.
349
00:21:03,428 --> 00:21:05,396
Of the thousands
of stars you see
350
00:21:05,430 --> 00:21:07,565
when you look up
at the night sky,
351
00:21:07,599 --> 00:21:08,899
every one of them is living
352
00:21:08,934 --> 00:21:11,068
in an interval
between two collapses:
353
00:21:11,103 --> 00:21:13,938
an initial collapse of a dark,
interstellar gas cloud
354
00:21:13,972 --> 00:21:15,573
to form the star,
355
00:21:15,607 --> 00:21:18,142
and a final collapse
of the luminous star
356
00:21:18,176 --> 00:21:20,911
on its way
to its ultimate fate.
357
00:21:20,946 --> 00:21:22,613
Gravity makes stars contract,
358
00:21:22,648 --> 00:21:24,849
unless some other force
intervenes.
359
00:21:24,883 --> 00:21:28,185
The Sun is a great, big ball
of incandescent gas.
360
00:21:28,220 --> 00:21:31,155
The super hot gas in its core
361
00:21:31,189 --> 00:21:33,190
pushes the Sun
to expand outward.
362
00:21:33,225 --> 00:21:36,027
At the same time,
the Sun's own gravity
363
00:21:36,061 --> 00:21:38,095
pulls it inward to contract.
364
00:21:38,130 --> 00:21:40,831
And our Sun is poised
between these two forces
365
00:21:40,866 --> 00:21:42,700
in a stable equilibrium
366
00:21:42,734 --> 00:21:45,870
between gravity
and nuclear fire,
367
00:21:45,904 --> 00:21:47,371
a balance it will maintain
368
00:21:47,406 --> 00:21:49,707
for another four billion years.
369
00:21:49,741 --> 00:21:52,043
But as the Sun
consumes hydrogen,
370
00:21:52,077 --> 00:21:55,012
its core very slowly shrinks,
371
00:21:55,047 --> 00:21:58,516
and the Sun's surface
gradually expands in response.
372
00:21:58,550 --> 00:21:59,984
It happens very slowly,
373
00:22:00,018 --> 00:22:01,485
imperceptibly,
374
00:22:01,520 --> 00:22:03,220
over the course
of millions of years.
375
00:22:03,255 --> 00:22:05,323
But in about a billion years,
376
00:22:05,357 --> 00:22:07,291
the Sun will be
ten percent brighter
377
00:22:07,326 --> 00:22:09,493
than it is today.
378
00:22:12,164 --> 00:22:14,131
Ten percent may not
sound like much,
379
00:22:14,166 --> 00:22:18,169
but that extra heat
will have a big effect on Earth.
380
00:22:25,277 --> 00:22:27,912
When the Sun finally exhausts
its nuclear fuel
381
00:22:27,946 --> 00:22:30,581
four or five
billion years from now,
382
00:22:30,615 --> 00:22:34,218
its gas will cool
and the pressure will fall.
383
00:22:34,252 --> 00:22:35,653
The Sun's interior
384
00:22:35,687 --> 00:22:37,188
can no longer support the weight
385
00:22:37,222 --> 00:22:38,856
of the outer layers,
386
00:22:38,890 --> 00:22:42,226
and the initial collapse
will resume.
387
00:22:42,260 --> 00:22:44,095
Nothing lasts forever.
388
00:22:44,129 --> 00:22:46,597
Even the stars die.
389
00:22:46,631 --> 00:22:48,899
Helium, the ash
390
00:22:48,934 --> 00:22:50,868
of ten billion years
of hydrogen fusion,
391
00:22:50,902 --> 00:22:53,104
has built up in the core.
392
00:22:53,138 --> 00:22:55,673
With no nuclear fire
to sustain its weight,
393
00:22:55,707 --> 00:22:58,175
the core collapses
until it becomes hot enough
394
00:22:58,210 --> 00:23:01,545
to start fusing helium
into carbon and oxygen.
395
00:23:01,580 --> 00:23:03,180
The core of the Sun
396
00:23:03,215 --> 00:23:05,416
is now much hotter
than it was before.
397
00:23:05,450 --> 00:23:08,185
Its atmosphere rapidly expands.
398
00:23:08,220 --> 00:23:11,288
Over the next billion years,
it'll become bloated
399
00:23:11,323 --> 00:23:13,791
to more than 100 times
its original size--
400
00:23:13,825 --> 00:23:16,927
a red giant star.
401
00:23:19,931 --> 00:23:22,133
It will envelop and devour
402
00:23:22,167 --> 00:23:24,735
the planets Mercury...
403
00:23:27,272 --> 00:23:29,640
...and Venus...
404
00:23:34,012 --> 00:23:36,113
...and possibly the Earth.
405
00:23:38,116 --> 00:23:39,950
I like to think that
406
00:23:39,985 --> 00:23:42,486
tens of millions of years
before that far distant future,
407
00:23:42,521 --> 00:23:45,723
if there still be life
born of Earth,
408
00:23:45,757 --> 00:23:49,360
it will have found new homes
among the stars.
409
00:23:51,329 --> 00:23:53,397
Once the Sun burns
through its helium,
410
00:23:53,432 --> 00:23:55,599
it will become highly unstable,
411
00:23:55,634 --> 00:23:58,536
casting off its outer layers
into space.
412
00:24:00,939 --> 00:24:02,673
The exposed, super hot core
413
00:24:02,707 --> 00:24:04,408
will flood its surroundings
414
00:24:04,443 --> 00:24:06,811
with high-energy
ultraviolet light.
415
00:24:09,047 --> 00:24:12,883
The atoms will perform
a wild, fluorescent dance.
416
00:24:19,057 --> 00:24:21,959
The Sun will collapse
like a soufflé,
417
00:24:21,993 --> 00:24:25,129
shrinking a hundredfold
to the size of the Earth.
418
00:24:25,163 --> 00:24:27,798
And at that point,
the Sun will be so dense
419
00:24:27,833 --> 00:24:30,367
that its overcrowded electrons
will push back,
420
00:24:30,402 --> 00:24:32,670
stopping any further
contraction.
421
00:24:32,704 --> 00:24:34,438
The kernel of light
at the center
422
00:24:34,473 --> 00:24:37,875
will be the only part
of the Sun that endures,
423
00:24:37,909 --> 00:24:41,345
a white dwarf star
that will go on shining dimly
424
00:24:41,379 --> 00:24:44,048
for another 100 billion years.
425
00:24:44,082 --> 00:24:46,383
Will the beings
of a distant future,
426
00:24:46,418 --> 00:24:48,819
sailing past
this wreck of a star,
427
00:24:48,854 --> 00:24:53,724
have any idea of the life
and worlds that it once warmed?
428
00:25:13,695 --> 00:25:15,763
DEGRASSE TYSON:
The psychedelic death shrouds
429
00:25:15,797 --> 00:25:18,799
of ordinary stars are fleeting,
430
00:25:18,833 --> 00:25:22,169
lasting only
tens of thousands of years
431
00:25:22,204 --> 00:25:25,606
before dissipating in
the interstellar gas and dust
432
00:25:25,640 --> 00:25:27,675
from which the new stars
will be born.
433
00:25:32,180 --> 00:25:34,582
The stars in
a binary star system
434
00:25:34,616 --> 00:25:36,684
can have a different fate.
435
00:25:36,718 --> 00:25:39,853
Sirius, the brightest star
in the night sky,
436
00:25:39,888 --> 00:25:42,957
has a very faint
stellar companion--
437
00:25:42,991 --> 00:25:44,358
a white dwarf.
438
00:25:44,392 --> 00:25:46,293
It was once a Sun-like star.
439
00:25:46,328 --> 00:25:49,096
Someday, when Sirius
runs out of fuel
440
00:25:49,130 --> 00:25:50,931
and becomes a red giant,
441
00:25:50,966 --> 00:25:53,767
it will shed its substance
onto the white dwarf.
442
00:25:53,802 --> 00:25:56,870
The intense gravity
of the companion
443
00:25:56,905 --> 00:25:58,505
will attract that gas,
444
00:25:58,540 --> 00:26:00,941
pulling it into
a spiraling disk.
445
00:26:00,976 --> 00:26:03,110
When the gas
from the larger star
446
00:26:03,144 --> 00:26:05,112
falls onto the surface
of the white dwarf,
447
00:26:05,146 --> 00:26:08,048
it will trigger
nuclear explosions.
448
00:26:11,853 --> 00:26:13,721
The greatest burst will release
449
00:26:13,755 --> 00:26:16,490
100,000 times more energy
than the Sun.
450
00:26:18,260 --> 00:26:21,328
Each one of those star bursts
is called a "nova,"
451
00:26:21,363 --> 00:26:24,565
from the Latin for "new."
452
00:26:24,599 --> 00:26:27,501
A star about 15 times
as massive as the Sun,
453
00:26:27,535 --> 00:26:30,471
one like Rigel,
the blue supergiant
454
00:26:30,505 --> 00:26:32,573
that forms the right foot
of Orion,
455
00:26:32,607 --> 00:26:34,408
has a different fate in store.
456
00:26:34,442 --> 00:26:38,045
Its collapse will not be stopped
by the pressure of electrons.
457
00:26:40,181 --> 00:26:43,384
The star will keep
falling in on itself,
458
00:26:43,418 --> 00:26:46,420
until its nuclei
become so overcrowded
459
00:26:46,454 --> 00:26:48,889
that they push back.
460
00:26:51,192 --> 00:26:54,228
Rigel will shrink down
about 100,000 times,
461
00:26:54,262 --> 00:26:57,564
until there's no space left
between the nuclei
462
00:26:57,599 --> 00:26:59,800
and it can shrink no more.
463
00:27:04,572 --> 00:27:06,006
At that point, it ignites
464
00:27:06,041 --> 00:27:10,044
a more powerful
nuclear reaction: a supernova.
465
00:27:15,417 --> 00:27:16,950
Most stellar evolution
466
00:27:16,985 --> 00:27:19,053
takes millions
or billions of years.
467
00:27:19,087 --> 00:27:20,788
But the interior collapse
468
00:27:20,822 --> 00:27:23,691
that triggers a supernova
explosion takes only seconds.
469
00:27:23,725 --> 00:27:27,194
What remains will be
an atomic nucleus
470
00:27:27,228 --> 00:27:29,897
the size of a small city--
471
00:27:29,931 --> 00:27:33,767
a rapidly rotating neutron star
called a pulsar.
472
00:27:46,448 --> 00:27:47,915
But for a star more than
473
00:27:47,949 --> 00:27:49,917
30 times as massive
as the Sun--
474
00:27:49,951 --> 00:27:52,920
a star like Alnilam,
in Orion's Belt--
475
00:27:52,954 --> 00:27:55,889
there will be no stopping
its collapse.
476
00:27:55,924 --> 00:27:57,624
In a few million years,
477
00:27:57,659 --> 00:27:59,426
when Alnilam runs out of fuel,
478
00:27:59,461 --> 00:28:01,462
it, too, will go supernova.
479
00:28:01,496 --> 00:28:04,832
The imploding core of Alnilam
480
00:28:04,866 --> 00:28:08,335
will be so massive
that not even nuclear forces
481
00:28:08,370 --> 00:28:11,338
will be strong enough
to hold off its collapse.
482
00:28:11,373 --> 00:28:14,241
Nothing can withstand
such gravity.
483
00:28:14,275 --> 00:28:16,543
And such a star has
an astonishing destiny.
484
00:28:21,349 --> 00:28:23,317
It will continues to collapse,
485
00:28:23,351 --> 00:28:25,919
crossing a boundary
in space-time
486
00:28:25,954 --> 00:28:28,122
called the "event horizon,"
487
00:28:28,156 --> 00:28:30,190
beyond which we cannot see.
488
00:28:30,225 --> 00:28:32,292
When it traverses
that frontier,
489
00:28:32,327 --> 00:28:35,562
the star will vanish
completely from sight.
490
00:28:37,465 --> 00:28:40,100
It will be inside a black hole,
491
00:28:40,135 --> 00:28:42,836
a place where gravity
is so strong
492
00:28:42,871 --> 00:28:46,306
that nothing, not even light,
can escape.
493
00:28:50,979 --> 00:28:52,179
But there's an even
494
00:28:52,213 --> 00:28:53,447
more dramatic fate
495
00:28:53,481 --> 00:28:55,516
that awaits a rare kind of star.
496
00:28:55,550 --> 00:28:57,684
There's one of them
in our galaxy.
497
00:28:57,719 --> 00:29:00,220
It's so unstable
that when it goes,
498
00:29:00,255 --> 00:29:03,690
it won't become a mere nova
or supernova.
499
00:29:03,725 --> 00:29:06,226
It'll become something
far more catastrophic:
500
00:29:06,261 --> 00:29:08,529
a hypernova.
501
00:29:08,563 --> 00:29:11,365
And it could happen
in our lifetime.
502
00:29:22,343 --> 00:29:25,179
There are few places on Earth
to get a better view
503
00:29:25,213 --> 00:29:28,248
of the night sky
than the Australian Outback.
504
00:29:30,051 --> 00:29:32,386
No buildings,
505
00:29:32,420 --> 00:29:35,322
no cars, streetlights,
nothing out here;
506
00:29:35,356 --> 00:29:37,191
just lots of starlight...
507
00:29:37,225 --> 00:29:39,560
and the occasional kangaroo.
508
00:29:39,594 --> 00:29:41,161
You can get
a particularly good view
509
00:29:41,196 --> 00:29:43,063
of the Milky Way from down here.
510
00:29:43,097 --> 00:29:44,765
The center of our galaxy
511
00:29:44,799 --> 00:29:46,400
rises high in the sky,
512
00:29:46,434 --> 00:29:48,435
and it arches across the heavens
513
00:29:48,470 --> 00:29:51,104
like the backbone of night.
514
00:29:51,139 --> 00:29:52,873
We live in a spiral galaxy.
515
00:29:52,907 --> 00:29:54,875
And when we look
at the Milky Way,
516
00:29:54,909 --> 00:29:58,846
we're seeing light from billions
of stars in its spiral disk.
517
00:29:58,880 --> 00:30:01,281
And under this beautiful
dark sky,
518
00:30:01,316 --> 00:30:04,918
you can see that the Milky Way
isn't a uniform band of light.
519
00:30:04,953 --> 00:30:08,055
There are dark patches,
breaks in the starlight.
520
00:30:08,089 --> 00:30:11,959
Those dark patches are caused
by interstellar dust.
521
00:30:11,993 --> 00:30:15,596
The dust blocks the starlight,
and there's lots of it.
522
00:30:17,332 --> 00:30:19,800
Most cultures looked up
at the stars
523
00:30:19,834 --> 00:30:21,134
and connected the dots
524
00:30:21,169 --> 00:30:23,303
to form familiar images
in the sky.
525
00:30:23,338 --> 00:30:25,439
Constellations.
526
00:30:30,612 --> 00:30:32,946
But the Aboriginal people
of Australia
527
00:30:32,981 --> 00:30:35,115
saw a pattern in the darkness
528
00:30:35,149 --> 00:30:37,217
running through the Milky Way.
529
00:30:37,252 --> 00:30:39,953
They saw an emu, a large bird
530
00:30:39,988 --> 00:30:42,256
native to this continent.
531
00:30:42,290 --> 00:30:46,193
Not in the stars,
but in the absence of stars.
532
00:30:49,364 --> 00:30:52,099
There are so many ways
to look at the night sky.
533
00:30:52,133 --> 00:30:55,135
For a million years or more,
we've watched the sky.
534
00:30:55,169 --> 00:30:56,837
And a lot's happened
in that time.
535
00:30:56,871 --> 00:31:00,741
Supernova explode in our galaxy
about once a century.
536
00:31:00,775 --> 00:31:03,810
If we could compress
all those nights of stargazing
537
00:31:03,845 --> 00:31:05,612
into a single minute,
538
00:31:05,647 --> 00:31:08,215
this is what we would see.
539
00:31:13,221 --> 00:31:15,355
Now, if our eyes
were telescopes,
540
00:31:15,390 --> 00:31:18,091
if they were light buckets
as big as wagon wheels
541
00:31:18,126 --> 00:31:21,762
and our vision was not limited
to just one kind of light,
542
00:31:21,796 --> 00:31:26,199
then this is the Milky Way
we would see.
543
00:31:26,234 --> 00:31:28,936
A galaxy in near-infrared light
544
00:31:28,970 --> 00:31:31,104
with streaming tendrils of dust
545
00:31:31,139 --> 00:31:33,807
hurled outward
by those exploding supernovas,
546
00:31:33,841 --> 00:31:35,809
silhouetted against a backdrop
547
00:31:35,843 --> 00:31:38,645
of countless stars.
548
00:31:38,680 --> 00:31:41,615
About 7,500 light-years away,
549
00:31:41,649 --> 00:31:43,850
in another part of our galaxy,
550
00:31:43,885 --> 00:31:46,019
there is a place of upheaval
551
00:31:46,054 --> 00:31:48,488
on an inconceivable scale.
552
00:31:55,129 --> 00:31:58,265
This is the Carina Nebula.
553
00:31:58,299 --> 00:32:00,701
A star-making machine.
554
00:32:04,505 --> 00:32:08,475
It takes a ray of light
50 years to cross it.
555
00:32:11,512 --> 00:32:14,848
The titanic stars born here
556
00:32:14,882 --> 00:32:17,117
sear the surrounding
gas and dust
557
00:32:17,151 --> 00:32:20,153
with their fierce
ultraviolet radiation.
558
00:32:20,188 --> 00:32:22,623
When a massive star dies,
559
00:32:22,657 --> 00:32:25,892
it blows itself to smithereens.
560
00:32:28,563 --> 00:32:31,264
Its substance is propelled
across the vastness
561
00:32:31,299 --> 00:32:33,300
to be stirred by starlight
562
00:32:33,334 --> 00:32:35,602
and gathered up by gravity.
563
00:32:35,637 --> 00:32:37,471
Stars to dust
564
00:32:37,505 --> 00:32:40,307
and dust to stars.
565
00:32:40,341 --> 00:32:43,210
In the cosmos,
nothing is wasted.
566
00:32:45,346 --> 00:32:49,249
But there's an upper limit
to how massive a star can be.
567
00:32:51,586 --> 00:32:53,987
Back in the 17th century,
when Edmond Halley
568
00:32:54,022 --> 00:32:56,690
crossed the equator to map
the southern constellations,
569
00:32:56,724 --> 00:32:59,960
Eta Carinae seemed
like just another faint star.
570
00:32:59,994 --> 00:33:02,796
But in 1843, Eta Carinae
571
00:33:02,830 --> 00:33:05,532
suddenly became the second
brightest star in the sky,
572
00:33:05,566 --> 00:33:08,235
outshined only by Sirius.
573
00:33:08,269 --> 00:33:10,871
And it's been
flipping out ever since.
574
00:33:13,341 --> 00:33:15,509
That dumbbell-shaped cloud
575
00:33:15,543 --> 00:33:18,745
is the expanding remnant
of that event.
576
00:33:23,284 --> 00:33:26,353
At its center
is one crazy star.
577
00:33:26,387 --> 00:33:28,255
Talk about unstable--
578
00:33:28,289 --> 00:33:30,223
Eta Carinae
is at least 100 times
579
00:33:30,258 --> 00:33:31,858
more massive than the Sun,
580
00:33:31,893 --> 00:33:35,162
and pouring out
five million times more light.
581
00:33:35,196 --> 00:33:40,667
It's pushing the upper limit
of what a star can be.
582
00:33:40,702 --> 00:33:43,503
What's more, there's
evidence that Eta Carinae
583
00:33:43,538 --> 00:33:47,274
is being gravitationally
tormented by an evil twin--
584
00:33:47,308 --> 00:33:50,343
another massive star
in orbit around it
585
00:33:50,378 --> 00:33:54,247
as close as Saturn is
to the Sun.
586
00:33:54,282 --> 00:33:58,218
The core of a supermassive star
pours out so much light
587
00:33:58,252 --> 00:34:01,755
that the outward pressure can
overwhelm the star's gravity.
588
00:34:01,789 --> 00:34:04,224
If a star is too massive,
589
00:34:04,258 --> 00:34:06,893
its radiation pressure
overpowers its gravity
590
00:34:06,928 --> 00:34:09,763
and blows the star apart.
591
00:34:11,566 --> 00:34:13,533
The fate of Eta Carinae
was sealed
592
00:34:13,568 --> 00:34:15,969
when it was born
millions of years ago.
593
00:34:16,003 --> 00:34:18,071
When it finally does blow up--
594
00:34:18,106 --> 00:34:20,407
and who knows,
maybe it already has;
595
00:34:20,441 --> 00:34:23,143
after all, we're looking at it
by light that left the star
596
00:34:23,177 --> 00:34:25,645
7,500 years ago--
597
00:34:25,680 --> 00:34:29,616
it will be a cataclysm unlike
anything we've seen before.
598
00:34:29,650 --> 00:34:31,585
A hypernova.
599
00:34:43,531 --> 00:34:46,500
An explosion so powerful,
it'll make a supernova
600
00:34:46,534 --> 00:34:49,402
seem like a firecracker
by comparison.
601
00:34:49,437 --> 00:34:51,605
If there are
nearby solar systems
602
00:34:51,639 --> 00:34:55,942
with planets harboring life,
their days are numbered.
603
00:34:55,977 --> 00:34:59,279
A hypernova spews
so much radiation into space--
604
00:34:59,313 --> 00:35:02,582
not just light,
but X-rays and gamma rays--
605
00:35:02,617 --> 00:35:04,618
that planets that are dozens
606
00:35:04,652 --> 00:35:06,987
or perhaps hundreds
of light-years away
607
00:35:07,021 --> 00:35:08,955
could be stripped
of their atmospheres
608
00:35:08,990 --> 00:35:11,625
and bathed in deadly radiation.
609
00:35:11,659 --> 00:35:13,126
It would wreak havoc
610
00:35:13,161 --> 00:35:15,862
in thousands
of nearby star systems.
611
00:35:15,897 --> 00:35:18,532
Right about now,
you're probably asking yourself,
612
00:35:18,566 --> 00:35:20,967
"Are we safe?"
613
00:35:21,002 --> 00:35:23,336
If Eta Carinae blows up,
614
00:35:23,371 --> 00:35:26,006
what happens to Earth?
615
00:35:26,040 --> 00:35:29,209
Rest assured,
Earth will be just fine.
616
00:35:29,243 --> 00:35:31,611
Remember,
we're 7,500 light-years
617
00:35:31,646 --> 00:35:33,313
away from Eta Carinae.
618
00:35:33,347 --> 00:35:35,448
The intensity of radiation
from a star,
619
00:35:35,483 --> 00:35:37,317
even an exploding star,
620
00:35:37,351 --> 00:35:39,553
falls off rapidly
with distance.
621
00:35:39,587 --> 00:35:42,989
But still, Eta Carinae
in its death throes
622
00:35:43,024 --> 00:35:44,991
will put on quite a show.
623
00:35:45,026 --> 00:35:47,494
It will light up the night
of the southern hemisphere
624
00:35:47,528 --> 00:35:49,863
with the brightness
of a second moon.
625
00:35:49,897 --> 00:35:54,167
The most dramatic swan song
a star can sing.
626
00:35:59,507 --> 00:36:02,175
Our ancestors
worshipped the Sun.
627
00:36:02,210 --> 00:36:05,245
And they were far from foolish.
628
00:36:05,279 --> 00:36:08,982
It makes good sense
to revere the Sun and stars,
629
00:36:09,016 --> 00:36:11,384
because we are their children.
630
00:36:11,419 --> 00:36:14,855
The silicon in the rocks,
the oxygen in the air,
631
00:36:14,889 --> 00:36:18,725
the carbon in our DNA,
the iron in our skyscrapers,
632
00:36:18,759 --> 00:36:21,027
the silver in our jewelry
633
00:36:21,062 --> 00:36:24,865
were all made in stars
billions of years ago.
634
00:36:24,899 --> 00:36:28,568
Our planet, our society
and we ourselves
635
00:36:28,603 --> 00:36:31,071
are stardust.
636
00:36:32,640 --> 00:36:35,775
Well, what is it
that makes the atoms dance?
637
00:36:35,810 --> 00:36:38,545
How is the energy
of a star transformed
638
00:36:38,579 --> 00:36:41,581
into everything
that happens in the world?
639
00:36:41,616 --> 00:36:43,850
What is energy?
640
00:36:43,885 --> 00:36:45,552
We're awash in it.
641
00:36:45,586 --> 00:36:48,355
When hydrogen atoms fuse
inside the Sun,
642
00:36:48,389 --> 00:36:50,056
they make helium atoms.
643
00:36:50,091 --> 00:36:52,559
And this fusion emits
a burst of energy
644
00:36:52,593 --> 00:36:55,862
that can wander inside the Sun
for ten million years
645
00:36:55,897 --> 00:36:58,365
before making its way
to the surface.
646
00:36:58,399 --> 00:37:00,901
And once there, it's free to fly
647
00:37:00,935 --> 00:37:03,103
straight from the Sun
to the Earth
648
00:37:03,137 --> 00:37:05,772
as visible light.
649
00:37:05,806 --> 00:37:08,942
If it should strike
the surface of a leaf,
650
00:37:08,976 --> 00:37:11,912
it will be stored in the plant
as chemical energy.
651
00:37:11,946 --> 00:37:13,947
Sunshine...
652
00:37:13,981 --> 00:37:15,849
into moonshine.
653
00:37:26,127 --> 00:37:28,528
(both speak Italian)
654
00:37:35,269 --> 00:37:38,972
I can feel my brain turning
the chemical energy of the wine
655
00:37:39,006 --> 00:37:41,141
into the electrical energy
of my thoughts
656
00:37:41,175 --> 00:37:42,909
and directing my vocal chords
657
00:37:42,944 --> 00:37:45,679
to produce the acoustic energy
of my voice.
658
00:37:45,713 --> 00:37:48,148
Such transformations of energy
659
00:37:48,182 --> 00:37:50,750
are happening everywhere
all the time.
660
00:37:50,785 --> 00:37:52,419
Energy from our star
661
00:37:52,453 --> 00:37:54,454
drives the wind
and the waves
662
00:37:54,488 --> 00:37:56,289
and the life
around us.
663
00:37:56,324 --> 00:37:59,759
How lucky we are to have this
vast source of clean energy
664
00:37:59,794 --> 00:38:03,697
falling like manna
from heaven on all of us.
665
00:38:03,731 --> 00:38:05,632
To Annie Jump Cannon,
666
00:38:05,666 --> 00:38:07,300
Henrietta Swan Leavitt
667
00:38:07,335 --> 00:38:08,969
and Cecilia Payne
668
00:38:09,003 --> 00:38:11,938
for blazing the trail
to modern astrophysics.
669
00:38:11,973 --> 00:38:15,875
And to all the sisters
of the Sun.
670
00:38:21,816 --> 00:38:25,785
There's no refuge
from change in the cosmos.
671
00:38:25,820 --> 00:38:28,655
Some ten or 20 million years
from now,
672
00:38:28,689 --> 00:38:30,957
it'll seem for a cosmic moment
673
00:38:30,992 --> 00:38:34,694
as if Orion is finally about
to catch the seven sisters.
674
00:38:34,729 --> 00:38:37,297
But before he has them
in his clutches,
675
00:38:37,331 --> 00:38:41,001
the biggest stars of Orion
will go supernova.
676
00:38:41,035 --> 00:38:44,137
Orion's pursuit of the Pleiades
will finally end,
677
00:38:44,171 --> 00:38:45,638
and the seven sisters
678
00:38:45,673 --> 00:38:48,508
will glide serenely
into the waiting arms
679
00:38:48,542 --> 00:38:50,910
of the Milky Way.
680
00:38:53,581 --> 00:38:56,349
We on Earth marvel--
and rightly so--
681
00:38:56,384 --> 00:38:59,185
at the return
of our solitary Sun.
682
00:38:59,220 --> 00:39:01,554
But from a planet
orbiting a star
683
00:39:01,589 --> 00:39:03,556
in a distant globular cluster,
684
00:39:03,591 --> 00:39:06,693
a still
more glorious dawn awaits.
685
00:39:07,962 --> 00:39:10,096
Not a sunrise...
686
00:39:10,131 --> 00:39:13,066
but a galaxy rise.
687
00:39:13,100 --> 00:39:17,170
A morning filled
with 200 billion suns.
688
00:39:17,204 --> 00:39:20,173
The rising of the Milky Way.
689
00:39:20,207 --> 00:39:23,910
An enormous spiral form
with collapsing gas clouds,
690
00:39:23,944 --> 00:39:27,580
condensing planetary systems,
luminous supergiants,
691
00:39:27,615 --> 00:39:31,518
stable middle-aged suns,
red giants, white dwarfs,
692
00:39:31,552 --> 00:39:33,953
planetary nebulas, supernovas,
693
00:39:33,988 --> 00:39:36,923
neutron stars,
pulsars, black holes
694
00:39:36,957 --> 00:39:39,459
and, there is
every reason to think,
695
00:39:39,493 --> 00:39:43,763
other exotic objects
that we have yet to discover.
696
00:39:43,798 --> 00:39:47,634
From such a world,
high above the Milky Way,
697
00:39:47,668 --> 00:39:50,303
it would be clear,
as it is beginning
698
00:39:50,337 --> 00:39:52,539
to be clear on our world,
699
00:39:52,573 --> 00:39:56,876
that we are made by the atoms
and the stars,
700
00:39:56,911 --> 00:39:58,945
that our matter and our form
701
00:39:58,979 --> 00:40:03,583
are forged by the great
and ancient cosmos,
702
00:40:03,617 --> 00:40:06,286
of which we are a part.
703
00:40:06,320 --> 00:40:06,286
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