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The Power To Destroy Entire Worlds! | Strip the Cosmos | Science Channel
The Power To Destroy Entire Worlds! | Strip the Cosmos | Science Channel
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Phụ đề (160)
0:03
Black holes.
0:07
The most powerful objects in the
0:09
universe,
0:11
capable of destroying entire worlds.
0:17
For decades, they have terrified us
0:23
with their mystery and darkness. The
0:27
reason why we call a black hole black is
0:29
because light cannot be emitted from
0:32
inside the black hole. It's a one-way
0:34
street. It can go in, but it can't come
0:36
out.
0:38
>> If you're close to a black hole, they're
0:40
terrifying. There's huge amounts of
0:42
matter that can fall into them. This
0:43
matter gets very hot. It gets torn
0:45
apart. It falls into this basically
0:48
infinitely deep hole in the universe
0:50
itself.
0:55
But there's more to black holes than
0:57
chaos and destruction.
1:00
>> The more we learn about black holes, the
1:01
more we understand they have a real
1:03
purpose in our universe. They're sort of
1:05
cosmic organizers. They bring things
1:07
together.
1:09
>> Could new discoveries change how we see
1:12
black holes?
1:14
>> I definitely think it's time for an
1:15
image makeover for black holes.
1:20
Black holes are more than darkness.
1:29
Stripping away a donut-shaped shroud of
1:31
cold dust on the outside
1:39
reveals a huge disc of cosmic debris
1:42
spinning at millions of miles an hour.
1:46
This is where the black hole feasts.
1:51
Gas, dust, shattered stars, and planets
1:55
all descend into the gaping mouth of the
1:58
black hole. It's called the event
2:01
horizon.
2:04
It's a perfectly dark sphere from which
2:07
no light can escape.
2:10
Inside, the laws of the cosmos break
2:14
down.
2:17
Black holes are a place where some of
2:19
the rules we think about in the universe
2:22
don't apply as well as they do out here.
2:24
When you're falling into a black hole,
2:25
you move faster and faster and faster
2:27
and you finally reach the speed of light
2:29
as you pass into the black hole itself.
2:31
But then what happens inside of that? We
2:34
don't know.
2:35
>> We are confronting something that the
2:37
human brain doesn't understand. Where
2:39
space and time itself break down, don't
2:41
behave the way we think of them. That's
2:44
going to push us to evolve, to
2:47
understand the very nature of reality
2:49
better.
2:52
>> 30 years ago, black holes were purely
2:55
theoretical,
2:57
a mathematical prediction made by
2:59
Einstein.
3:02
But now we know
3:05
they're very real.
3:08
This is our galaxy, the Milky Way.
3:15
stripping away its stars, planets,
3:18
rocks, and dust
3:22
reveals a dark secret.
3:26
Lurking in the shadows is a massive
3:28
black hole,
3:30
Sagittarius, a star,
3:34
4 million times the mass of our sun and
3:37
just 26,000 light years from Earth.
3:42
Studying this Titan offers us a chance
3:45
to understand how black holes truly
3:49
work.
3:55
On top of Hawaii's tallest mountain,
3:57
Monaka,
3:59
scientists at the Kek Observatory do
4:02
just that.
4:06
Astronomer James like
4:09
studies Sagittarius AAR.
4:15
It's so unique to have a black hole that
4:17
massive that close to us because all the
4:20
other ones that are that massive are so
4:22
far away in other galaxies.
4:26
Getting to his office requires a 14,000
4:29
ft climb along a steep and winding dirt
4:32
road.
4:36
I've loved telescopes for a long time
4:38
and these are the these are the biggest
4:40
and the best. So if you want to get the
4:42
finest objects in the universe, if you
4:44
want to look at the finest detail, you
4:45
have to come to CEK.
4:47
Takes your breath away.
4:51
Today, James prepares Kek's 300 ton
4:55
telescope
4:57
to monitor Sagittarius AAR. The
5:01
telescope is going to come very close
5:02
right behind me.
5:04
You know, it takes a dedicated crew of
5:06
20 guys to get this thing running every
5:08
night of the year. It's a very complex
5:10
machine.
5:13
The constant movement of the Earth's
5:15
atmosphere,
5:16
bends light, and makes stars twinkle.
5:21
This distortion stops scientists from
5:23
getting a clear view of the Milky Way.
5:29
But the team at KEK has cracked this
5:31
problem.
5:33
As night falls, James shoots a bright
5:36
laser 50 miles up into the atmosphere.
5:40
>> We take pictures of the return from that
5:42
laser. It gets fuzzed up by the
5:44
atmosphere just the same way as the
5:45
natural star does.
5:47
>> By altering the telescope's mirrors,
5:50
James brings this beam of light into
5:52
focus.
5:55
This allows him to calibrate the
5:57
telescope and obtain the sharpest images
5:59
ever seen of objects in the Milky Way.
6:03
>> It's a revolution in astronomy. This is
6:06
technology that was dreamed about for
6:07
years. It's a bit of a game changer and
6:10
we now can see things that we never
6:11
could see before.
6:13
>> James and his team are making startling
6:16
discoveries that are changing our
6:18
understanding of how black holes work.
6:23
They have detected a mysterious object
6:26
close to Sagittarius A star.
6:34
It's called G2,
6:37
a cloud of interstellar gas which may
6:40
contain a star.
6:44
Its future is bleak.
6:47
Scientists believe the black hole will
6:50
slingshot part of the cloud into space
6:58
and then gorge on the remains,
7:02
growing even more massive and powerful.
7:13
G2 happens to be one of the closest
7:16
objects to the black hole. Anytime you
7:19
get that close to that extreme of
7:22
environment, you get to see new physics.
7:25
You get to see fantastic things.
7:28
Soon, the team will see a black hole
7:30
feeding for the very first time.
7:40
Sagittarius A star is 4 million times
7:44
more massive than the sun,
7:48
but 300 million light years away,
7:51
there's a black hole 5,000 times larger.
7:57
Deep inside a galaxy called NGC 4889
8:03
is the biggest black hole ever found.
8:08
It's so powerful it can shred super
8:11
giant stars that come too close.
8:17
What gives black holes the power to
8:20
destroy entire worlds?
