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Are The First Stars Really Still Out There?

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0:01

okay

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look

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up

0:07

when you peer at the heavens on a clear

0:09

moonless night you can see the stars of

0:12

our galaxy strewn across the black

0:15

we cannot help but seek recognizable

0:17

outlines by tracing our finger from one

0:20

star to the next like searching for

0:22

shapes in clouds

0:25

we see ourselves in the groups of stars

0:27

assigning them names and meaning to our

0:30

eyes the individual Stars making up

0:33

these constellations seem uniform

0:35

remarkable only when forming part of a

0:37

larger group

0:39

but with a powerful enough telescope the

0:41

truth reveals itself and we can finally

0:44

reshape the sky according to science not

0:47

symbolism

0:50

so let us take a tour of the Stars

0:53

in order of their Rarity

0:57

we begin with the failed Stars Brown

1:00

dwarfs below eight percent of the mass

1:03

of the Sun these are protostars without

1:05

the gravitational clout to spark Fusion

1:08

in their cores the Galaxy is littered

1:10

with these failures one for every

1:12

successful star

1:14

stars in the prime of their Stellar

1:16

lives make up 90 of the several hundred

1:19

billion in the Milky Way our sun is one

1:22

part of the yellow dwarf category in

1:24

which only about seven percent of stars

1:26

fall a relative Rarity far more numerous

1:29

are the cooler and smaller red dwarfs

1:31

that make up a much larger 75 percent as

1:34

we look for stars with larger masses the

1:36

search becomes more difficult thanks to

1:38

their volatility and short lifespan

1:41

white supergiants like cannipus the

1:44

second brightest star in the sky despite

1:45

its great distance from us comprised

1:47

less than one percent of the start in

1:49

our galaxy and more extreme hypergiants

1:52

like the largest known star Stevenson

1:54

218 are even harder to find their size

1:58

resulting in strong Stellar winds where

2:00

Stellar material the mass of Jupiter is

2:02

blown away in single events almost

2:05

evaporating the star as fast as it grows

2:08

While most stars are enjoying their best

2:10

life there are tens of billions in the

2:12

final stages of their Stellar Revolution

2:14

smaller Stars such as the sun will

2:17

eventually puff out into red giants a

2:19

fleeting midpoint on the way to a white

2:21

dwarf these dense and compact Stellar

2:25

remnants comprise about five percent of

2:27

stars in the present day though

2:29

eventually 97 percent of the Milky Ways

2:32

Stellar population will shrivel into

2:34

these gently fading spheres

2:36

neutron stars and black holes are exotic

2:39

high density phenomena making up 0.5

2:41

percent and point zero zero zero five

2:44

percent of our Galaxy's population

2:45

respectively and the result of

2:47

supernovae by the largest Stars while

2:50

spinning neutron stars pulsars have been

2:53

observed in their thousands since the

2:54

1960s we've only observed 31 of their

2:58

most extreme form

3:01

natash

3:02

this type of neutron star has a magnetic

3:05

field a thousand trillion times stronger

3:07

than that of the earth and star Quakes

3:10

on their surface produce powerful bursts

3:12

of gamma rays these star Quakes are also

3:15

much stronger than our equivalent

3:17

reaching up to 23 on the Richter scale

3:23

but even that is still not the rarest

3:26

form of star scientists predict could be

3:29

out there

3:32

in its early days the universe was

3:35

filled with hypergiants but they were

3:38

much different to those we see now the

3:41

first lights that kindled in the cosmos

3:43

were vast hungry and short-lived living

3:46

and dying in a cosmic blink of an eye

3:49

known as population 3 stars they were

3:53

the ancestors of us all and they may

3:56

still linger out there in the black

3:58

the rarest stars in the universe

4:14

how much time do you have a plank time

4:17

is the shortest possible moment of time

4:19

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4:21

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4:24

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4:26

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4:28

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4:31

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[Music]

5:52

in Japanese mythology the god of

5:54

creation gives birth to many deities but

5:57

three a particularly Divine tsukuyomi

6:00

the moon God susano the god of Storms

6:03

and seas and Amaterasu the goddess of

6:06

the Sun the highest deity of all

6:09

in the most famous Legend involving the

6:11

sun goddess susano threw a holy horse

6:13

into a loom flaying it alive and killing

6:16

a nearby weaving Maiden Amaterasu was so

6:19

upset that she fled and hid in a cave

6:21

blocking the entrance

6:23

Sun disappeared from the sky and a

6:26

permanent night fell on Japan this

6:29

eternal night only ended when the other

6:31

gods and goddesses staged a ritual

6:33

outside the cave laughing so loudly that

6:36

Amaterasu could not help but come out to

6:38

see what was going on the deities sealed

6:41

the cave shut as she emerged and Japan

6:43

once again became the Land of the Rising

6:47

Sun

6:48

[Music]

6:52

the sun is essential to all life on

6:55

Earth its calm and predictability

6:57

nurtures plants animals and humans alike

6:59

surrounding them with light and warmth

7:02

it is no wonder then that right from

7:04

where the earliest civilizations formed

7:06

the sun has often been portrayed as a

7:08

benevolent God want to be feared perhaps

7:11

but only because of its possible

7:12

disappearance

7:13

now of course we understand that stars

7:16

are physical entities still full of

7:18

wonder but explainable using modern

7:20

science

7:22

for the longest time we were reliant on

7:24

only our own eyes until Galileo ground

7:26

his artificial lenses and magnified the

7:29

skies with his telescope

7:31

the haze of the Milky Way resolved into

7:34

millions of stars and even some

7:36

individual Stars revealed themselves to

7:38

be binary systems hundreds of years

7:41

passed and we cataloged the positions of

7:43

these stars with increasing accuracy and

7:46

with the Advent of spectroscopy we could

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even begin to identify barcodes

7:50

individual to each star the gaps in

7:53

which revealed which heavy elements were

7:54

present in that Stellar atmosphere

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we could identify what these distant

7:59

Suns

8:00

were really made of

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but that was not all

8:06

[Music]

8:10

chemical elements comprise a nucleus

8:13

surrounded by electrons these electrons

8:15

naturally rest in the ground state but

8:18

can be excited up into different energy

8:19

levels by the absorption of a photon

8:21

with an energy equal to a particular

8:23

energy gap

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