Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:04,715 --> 00:00:08,260
NARRATOR:
Humans are natural-born explorers.
2
00:00:08,468 --> 00:00:12,848
We charge into uncharted territory
and seek out the unknown.
3
00:00:14,433 --> 00:00:16,476
We've mapped nearly every inch
of Mother Earth...
4
00:00:18,478 --> 00:00:20,856
...and left tracks on the moon.
5
00:00:21,064 --> 00:00:23,442
But to set foot on another planet...
6
00:00:23,650 --> 00:00:25,944
...to travel beyond our solar system...
7
00:00:26,111 --> 00:00:28,614
...that is a dream for the future.
8
00:00:33,452 --> 00:00:37,831
A dream that comes to life
in the feature film Interstellar.
9
00:00:39,416 --> 00:00:45,214
BRAND: We must think not as individuals
but as a species.
10
00:00:45,380 --> 00:00:49,218
We must confront the reality
of interstellar travel.
11
00:00:54,223 --> 00:00:59,728
NARRATOR: The film Interstellar deals with the
quest for new worlds and the fate of humanity.
12
00:01:00,479 --> 00:01:02,731
Sound like the stuff of science fiction?
13
00:01:03,315 --> 00:01:04,733
Maybe.
14
00:01:04,900 --> 00:01:09,571
But the foundations of this film
are rooted in real science...
15
00:01:09,738 --> 00:01:14,326
...thanks to the involvement
of renowned astrophysicist Kip Thorne.
16
00:01:14,493 --> 00:01:18,247
In Interstellar,
one of the most important features...
17
00:01:18,413 --> 00:01:22,918
...is the way that the science
is totally embedded in the film.
18
00:01:23,085 --> 00:01:24,878
There are some wild things in here.
19
00:01:26,004 --> 00:01:31,260
NARRATOR: Beyond fantasy and fiction,
this is the real science of Interstellar.
20
00:01:39,768 --> 00:01:42,771
Space travel has been a staple of the movies
from the very beginning...
21
00:01:42,938 --> 00:01:46,525
...but the feature film Interstellar
has a unique pedigree.
22
00:01:46,692 --> 00:01:49,444
It was inspired in part
by the work of Kip Thorne...
23
00:01:51,655 --> 00:01:55,409
...an authority on astrophysics,
gravitational waves...
24
00:01:55,575 --> 00:01:58,328
...and the warping of space-time.
25
00:01:58,495 --> 00:02:01,540
He's also an executive producer
on the film.
26
00:02:01,873 --> 00:02:07,713
In Interstellar, real science was built
into the fabric of the film from the outset.
27
00:02:08,213 --> 00:02:13,927
The other major players in this film,
they all respected the science...
28
00:02:14,094 --> 00:02:18,015
...and they worked with me to see
that the science was well incorporated.
29
00:02:18,181 --> 00:02:24,646
Can you tell me what the easiest definition
of what a singularity is?
30
00:02:24,813 --> 00:02:29,860
Kip and myself meshed well
in terms of trying to use current thinking...
31
00:02:30,027 --> 00:02:33,155
...current scientific understanding
to drive the narrative.
32
00:02:33,322 --> 00:02:34,698
The language we use...
33
00:02:34,865 --> 00:02:41,204
...is it's a place where the curvature
of space and time gets infinitely high.
34
00:02:41,371 --> 00:02:42,456
So we're good, okay.
35
00:02:42,622 --> 00:02:46,835
And we just hope that the research we've done
and the conversations I'd had with Kip...
36
00:02:47,002 --> 00:02:50,380
...and that Chris had had with Kip
informed the narrative...
37
00:02:50,547 --> 00:02:52,424
...and that the audience would feel that.
38
00:02:52,591 --> 00:02:55,719
NOLAN:
Why simply imagine, fantasize...
39
00:02:55,886 --> 00:02:59,514
...about things that might happen in space
or on an interstellar journey?
40
00:02:59,681 --> 00:03:02,851
Why not actually look
at, uh, the real science there?
41
00:03:05,604 --> 00:03:06,980
It's an Indian surveillance drone.
42
00:03:07,147 --> 00:03:09,066
NARRATOR:
Interstellar takes place in a future...
43
00:03:09,232 --> 00:03:12,986
...where living conditions on Earth
threaten the survival of humanity.
44
00:03:13,904 --> 00:03:17,032
BRAND: Your daughter's generation
will be the last to survive on Earth.
45
00:03:17,199 --> 00:03:20,535
COOPER: Now you need to tell me
what your plan is to save the world.
46
00:03:20,702 --> 00:03:23,914
BRAND: We're not meant to save the world,
we're meant to leave it.
47
00:03:24,873 --> 00:03:28,502
One of the things that the film explores is,
do we belong on Earth...
48
00:03:28,668 --> 00:03:31,797
...and should we be staying on Earth...
49
00:03:31,963 --> 00:03:35,008
...and if there is anything else out there,
should we be exploring that?
50
00:03:35,342 --> 00:03:36,635
Here we go.
51
00:03:36,802 --> 00:03:39,429
NARRATOR: In the film,
the crew seeks a new place to call home.
52
00:03:39,596 --> 00:03:41,264
A planet that can sustain life.
53
00:03:42,099 --> 00:03:43,225
Human life.
54
00:03:43,392 --> 00:03:44,643
- I'm not gonna make it!
- Yes, you are.
55
00:03:44,810 --> 00:03:47,771
It's an exciting concept
that there may be other worlds out there.
56
00:03:48,438 --> 00:03:51,149
Well, what are those worlds
and what could they be...
57
00:03:51,316 --> 00:03:53,235
...and is there a place for us out there?
58
00:03:53,735 --> 00:03:55,320
NARRATOR:
The search for another Earth...
59
00:03:55,487 --> 00:03:58,281
...sounds like a job
for the explorers of tomorrow...
60
00:03:58,782 --> 00:04:01,576
...but it's happening right now.
61
00:04:05,038 --> 00:04:09,251
Astrophysicist Natalie Batalha
is a passionate planet hunter.
62
00:04:09,418 --> 00:04:13,171
BATALHA: I think the only way that we're going
to really understand our place in the galaxy...
63
00:04:13,338 --> 00:04:18,927
...is by looking at this broad picture
and understanding the diversity of all planets.
64
00:04:19,094 --> 00:04:21,138
Twenty or 30 years ago, we didn't know...
65
00:04:21,304 --> 00:04:25,725
...of any other planets orbiting normal stars
like our own sun.
66
00:04:26,435 --> 00:04:29,312
NARRATOR: Natalie has helped
rewrite that story as mission scientist...
67
00:04:29,479 --> 00:04:31,398
...for NASA's Kepler space telescope.
68
00:04:31,565 --> 00:04:33,859
BATALHA:
Kepler's objective is very simple.
69
00:04:34,025 --> 00:04:37,320
It's to determine the fraction of stars
in our galaxy...
70
00:04:37,487 --> 00:04:41,283
...that harbor potentially habitable
Earth-size planets.
71
00:04:41,450 --> 00:04:43,743
NARRATOR: And what makes a planet
potentially habitable?
72
00:04:43,910 --> 00:04:46,955
The one ingredient that we think
is common to all life forms...
73
00:04:47,122 --> 00:04:49,791
...is this requirement of liquid water.
74
00:04:49,958 --> 00:04:52,544
So that's why we look for planets
that have rocky surfaces...
75
00:04:52,711 --> 00:04:53,879
...where water could pool...
76
00:04:54,212 --> 00:04:57,132
...and that are receiving the right amount
of energy from the star...
77
00:04:57,299 --> 00:05:01,136
...where the water wouldn't be locked up
in a frozen state because the planet is so cold...
78
00:05:01,303 --> 00:05:04,848
...nor would it be evaporated away
because the planet is too hot.
79
00:05:05,015 --> 00:05:09,436
We call it the Goldilocks Zone,
where liquid water could potentially exist.
80
00:05:10,437 --> 00:05:12,647
NARRATOR:
Launched in 2009, Kepler stared...
81
00:05:12,814 --> 00:05:17,319
...at one small patch of the Milky Way
for four years straight.
82
00:05:17,486 --> 00:05:21,865
Compared to stars,
planets are too tiny for Kepler to spot...
83
00:05:22,657 --> 00:05:24,159
...but it can detect their shadows.
84
00:05:24,326 --> 00:05:29,581
BATALHA: Every planet orbiting a luminous
object is casting a shadow out into space.
85
00:05:29,748 --> 00:05:32,417
The Kepler spacecraft makes use
of that fact...
86
00:05:32,584 --> 00:05:37,214
...waiting for a planet
in its orbit about the star...
87
00:05:37,380 --> 00:05:41,176
...to pass directly between
the disc of the star and the spacecraft...
88
00:05:41,676 --> 00:05:46,097
...and the telescope perceives that
as a dimming of light.
89
00:05:46,264 --> 00:05:49,518
NARRATOR: This simple method
has revealed thousands of exoplanets.
90
00:05:50,268 --> 00:05:53,647
Planets orbiting other stars in our galaxy.
91
00:05:53,813 --> 00:05:55,023
What we've learned so far...
92
00:05:55,190 --> 00:06:00,570
...is that literally every star in the galaxy
has at least one planet.
93
00:06:01,071 --> 00:06:05,158
There's an amazing diversity
of exoplanets out there...
94
00:06:05,325 --> 00:06:07,327
...and we've found very exotic worlds.
95
00:06:07,994 --> 00:06:12,249
Two hundred light-years away,
there is a Saturn-size planet orbiting...
96
00:06:12,415 --> 00:06:14,918
...not one, but two stars.
97
00:06:15,085 --> 00:06:18,296
So if you were living
on a world like Kepler-16b...
98
00:06:18,463 --> 00:06:22,634
...you would see in the sky two stars
rising in the east, setting in the west...
99
00:06:22,801 --> 00:06:27,472
...continuously changing position
as they orbit one another.
100
00:06:30,141 --> 00:06:33,562
This is an artist's rendition
of the planet Kepler-10b.
101
00:06:33,728 --> 00:06:39,901
It's orbiting 23 times closer to its parent star
than Mercury is to our own sun.
102
00:06:40,068 --> 00:06:45,198
So this star-facing side is just
being blasted by stellar radiation...
103
00:06:45,574 --> 00:06:49,661
...creating temperatures
in excess of that required to melt iron.
104
00:06:49,828 --> 00:06:54,124
The planet has an entire hemisphere
larger than the Pacific Ocean...
105
00:06:54,291 --> 00:06:57,294
...which is an ocean,
but it's not an ocean of water.
106
00:06:57,460 --> 00:06:59,671
It's an ocean of molten lava.
107
00:07:00,714 --> 00:07:03,049
NARRATOR:
Not an attractive destination.
108
00:07:04,718 --> 00:07:08,888
But Kepler recently found us
a possible second home.
109
00:07:09,055 --> 00:07:12,767
This is an artist's concept
of the Kepler-186 planetary system.
110
00:07:12,934 --> 00:07:15,979
Five planets orbiting this M-type star...
111
00:07:16,146 --> 00:07:20,275
...and the outermost planet is Kepler-186f.
112
00:07:21,109 --> 00:07:26,448
Our first discovery of an Earth-size planet
in the habitable zone of a normal star.
113
00:07:26,615 --> 00:07:32,370
When I think about Kepler-186f,
I try to imagine it as a real place...
114
00:07:32,537 --> 00:07:34,789
...because it is a real place.
115
00:07:34,956 --> 00:07:38,001
We know that it could be rocky,
it's the same size as Earth...
116
00:07:38,168 --> 00:07:40,837
...so I do imagine a rocky surface.
117
00:07:41,546 --> 00:07:45,592
We don't know that it has a liquid ocean,
but we can certainly imagine one.
118
00:07:46,092 --> 00:07:48,428
And then, all of a sudden
in your imagination...
119
00:07:48,595 --> 00:07:51,389
...you internalize the existence
of this world out there...
120
00:07:51,556 --> 00:07:54,893
...that there is a place
that could be very, very much like Earth.
121
00:07:55,977 --> 00:08:00,482
NARRATOR: So when do we set sail
for these distant shores?
122
00:08:00,649 --> 00:08:02,651
Reality check.
123
00:08:02,942 --> 00:08:08,114
Kepler-186f is nearly 3 quadrillion miles
from Earth.
124
00:08:08,281 --> 00:08:11,117
Otherwise put, 500 light-years away.
125
00:08:11,910 --> 00:08:16,164
That's a journey of 500 years
at the speed of light.
126
00:08:16,456 --> 00:08:19,584
But no thing can travel as fast as light.
127
00:08:19,751 --> 00:08:22,754
At best, our spacecrafts
are thousands of times slower.
128
00:08:23,088 --> 00:08:25,757
Even the spaceships in Interstellar
don't come close.
129
00:08:25,924 --> 00:08:29,094
BRAND: We need the bravest humans
to find us a new home.
130
00:08:29,260 --> 00:08:32,305
COOPER: But the nearest star
is over a thousand years away.
131
00:08:32,472 --> 00:08:34,099
- Hence the bravery.
- Okay.
132
00:08:34,474 --> 00:08:38,019
NARRATOR: So how do they reach new worlds
beyond our solar system?
133
00:08:39,437 --> 00:08:42,816
They take a walk on the warp side
of space and time.
134
00:08:47,404 --> 00:08:49,239
MURPH:
You have no idea when you're coming back.
135
00:08:50,323 --> 00:08:53,201
AMELIA: Couldn't you have told her
you were going to save the world?
136
00:08:53,368 --> 00:08:54,619
No.
137
00:08:56,121 --> 00:08:58,248
I'm coming back.
138
00:08:58,915 --> 00:09:04,462
NARRATOR: When we journey to a far-off place,
we travel not just in space but also in time...
139
00:09:04,629 --> 00:09:07,257
...as we move into the future.
140
00:09:08,633 --> 00:09:15,306
Until about a century ago, scientists believed
that space and time were entirely separate.
141
00:09:16,266 --> 00:09:22,647
Theoretical physicist Sean Carroll explains
how Albert Einstein overturned that idea.
142
00:09:23,022 --> 00:09:24,858
CARROLL:
One of Einstein's great insights...
143
00:09:25,024 --> 00:09:27,485
...was that space and time
were related to each other...
144
00:09:27,652 --> 00:09:29,529
...where you have space and you have time.
145
00:09:29,696 --> 00:09:33,450
Einstein says, "There's only one thing
which we call space-time."
146
00:09:34,617 --> 00:09:37,036
And then he says, "This space-time thing...
147
00:09:37,203 --> 00:09:41,207
...it's not just the stage
on which all the action plays out.
148
00:09:41,374 --> 00:09:42,542
It's an actor itself."
149
00:09:45,712 --> 00:09:50,383
Space-time can change, it can move,
it can bend, and it can warp.
150
00:09:53,678 --> 00:09:59,058
NARRATOR: Einstein's theory of relativity
states that space-time is like a flexible fabric.
151
00:09:59,225 --> 00:10:06,107
The objects embedded in it:
The sun, planets, even us, warp that fabric.
152
00:10:06,608 --> 00:10:10,779
And the consequence of that warping
is what we call gravity.
153
00:10:10,945 --> 00:10:14,908
The more massive the object,
the more space-time is warped...
154
00:10:15,074 --> 00:10:17,452
...and the greater the gravity.
155
00:10:21,915 --> 00:10:23,416
We feel gravity.
156
00:10:25,460 --> 00:10:29,589
The flexibility of space-time
is harder to grasp on a gut level...
157
00:10:29,756 --> 00:10:32,383
...but its effects are measurable.
158
00:10:35,261 --> 00:10:41,267
As Sean demonstrates, the greater the gravity,
the more slowly time flows.
159
00:10:41,434 --> 00:10:44,229
CARROLL: For example,
if I were on the ground floor with a clock...
160
00:10:44,395 --> 00:10:46,397
...a super accurate atomic clock...
161
00:10:46,564 --> 00:10:49,234
...and a twin of mine was up
on the top floor of a building...
162
00:10:49,400 --> 00:10:51,236
...with an equally accurate atomic clock...
163
00:10:51,402 --> 00:10:55,824
...if we later on compared them,
mine would have ticked off fewer seconds.
164
00:10:57,242 --> 00:11:01,162
NARRATOR: On the ground floor,
Sean experiences slightly more gravity...
165
00:11:01,329 --> 00:11:03,540
...than his twin on the top floor.
166
00:11:03,706 --> 00:11:07,418
He also experiences slightly less time
than his twin.
167
00:11:08,127 --> 00:11:11,214
The difference is tiny, but real.
168
00:11:11,381 --> 00:11:13,341
And there are practical applications.
169
00:11:13,508 --> 00:11:17,178
CARROLL: For example, the GPS system,
the Global Positioning System...
170
00:11:17,345 --> 00:11:20,557
...that is a very, very precise set of clocks...
171
00:11:20,723 --> 00:11:23,017
...on satellites orbiting around the Earth...
172
00:11:23,184 --> 00:11:27,397
...and that orbit is in a slightly different
gravitational field than we are in down here.
173
00:11:27,564 --> 00:11:32,151
So the fact that time moves differently
here on the surface of the Earth...
174
00:11:32,318 --> 00:11:34,654
...than in the satellite orbit,
is very, very important...
175
00:11:34,821 --> 00:11:36,906
...to getting the GPS to work correctly.
176
00:11:37,574 --> 00:11:41,744
NARRATOR: Time on a GPS satellite clock
advances faster than a clock on Earth...
177
00:11:41,911 --> 00:11:44,247
...by about 38 microseconds per day...
178
00:11:44,622 --> 00:11:47,000
...so the system's computers correct for that.
179
00:11:49,586 --> 00:11:52,755
Motion also affects our experience
of space-time.
180
00:11:52,922 --> 00:11:55,675
CARROLL:
The best way to say it is just staying still...
181
00:11:55,842 --> 00:11:58,595
...means that you experience
the most time that you can.
182
00:11:58,761 --> 00:12:02,599
Moving around and doing things
means you experience less time.
183
00:12:02,765 --> 00:12:07,604
NARRATOR: Let's revisit Sean at the wheel
of his car and his twin on a park bench.
184
00:12:07,770 --> 00:12:10,899
If you move out on your car,
and then you come back...
185
00:12:11,274 --> 00:12:13,860
...compared to the person
who stayed behind...
186
00:12:14,027 --> 00:12:16,446
...your clock that you took with you
on that journey...
187
00:12:16,613 --> 00:12:20,408
...will have experienced a little bit less time
than the one who stayed behind.
188
00:12:22,911 --> 00:12:25,914
NARRATOR: We normally move too slowly
to notice the effect.
189
00:12:26,748 --> 00:12:29,959
But if Sean could drive
near the speed of light...
190
00:12:31,461 --> 00:12:35,298
...he could race across the United States
and back again a million times...
191
00:12:35,465 --> 00:12:38,384
...and experience less
than a second of time...
192
00:12:38,551 --> 00:12:40,345
...while the twin he left behind...
193
00:12:40,511 --> 00:12:43,431
...would endure hours of waiting
for Sean's return.
194
00:12:44,682 --> 00:12:49,562
In other words, Sean would've traveled
into the future compared to his twin.
195
00:12:51,356 --> 00:12:53,608
This means space travel may get tricky
in years to come.
196
00:12:54,525 --> 00:12:58,446
The faster our spaceships,
the greater the gravity fields we encounter...
197
00:12:58,613 --> 00:13:02,492
...the further out of sync we may become
with those we leave behind.
198
00:13:02,659 --> 00:13:06,204
COOPER:
So if we find a home, then what?
199
00:13:06,371 --> 00:13:08,790
Every hour is seven years back on Earth.
200
00:13:09,207 --> 00:13:14,837
NARRATOR: The relativity of time is the source
of hardship and heartbreak in Interstellar.
201
00:13:16,172 --> 00:13:18,967
The theory of relativity
is fascinating all by itself...
202
00:13:19,133 --> 00:13:22,053
...but it immediately becomes
something very emotional...
203
00:13:22,220 --> 00:13:25,515
...when you talk about
the distances between people.
204
00:13:26,557 --> 00:13:29,268
You know, we all spend time
away from our families.
205
00:13:29,435 --> 00:13:33,982
I just thought, what if you could take that
to its logical and very bittersweet extreme?
206
00:13:34,148 --> 00:13:38,403
NOLAN: For me, it was very exciting
to be able to examine the concept...
207
00:13:38,569 --> 00:13:40,947
...of the subjective experience of time.
208
00:13:41,114 --> 00:13:43,658
It's really the first time
I've had an objective structure...
209
00:13:43,825 --> 00:13:46,744
...around the film saying
that time literally is relative...
210
00:13:46,911 --> 00:13:50,289
...that we all experience time differently
depending on where we are in the universe.
211
00:13:51,249 --> 00:13:54,127
NARRATOR: But the warping of space-time
may also provide shortcuts...
212
00:13:54,585 --> 00:13:57,213
...that could make interstellar travel a snap.
213
00:13:58,506 --> 00:13:59,716
Wormholes.
214
00:14:00,717 --> 00:14:02,510
They're a staple of science fiction...
215
00:14:03,928 --> 00:14:06,347
...but they're based on real science.
216
00:14:06,973 --> 00:14:12,061
Einstein's relativistic laws
govern the warping of space and time...
217
00:14:12,228 --> 00:14:16,357
...and they say that wormholes might exist,
they could exist.
218
00:14:16,816 --> 00:14:20,236
So this dates all the way back to 1916.
219
00:14:22,155 --> 00:14:26,451
CARROLL: A wormhole is a particular way
that space and time can be curved.
220
00:14:26,617 --> 00:14:30,997
It's like adding a little tube
that connects two parts of space.
221
00:14:31,622 --> 00:14:36,627
The basic idea is that if you're an ant
and you live on the surface of the apple...
222
00:14:36,794 --> 00:14:39,422
...the surface of the apple
is your entire universe.
223
00:14:40,048 --> 00:14:44,302
You can go around the outside
through the universe itself...
224
00:14:44,469 --> 00:14:47,180
...or you can go through the wormhole.
225
00:14:47,472 --> 00:14:52,143
NARRATOR: But Einstein's equations also
predict that if wormholes do form in nature...
226
00:14:52,310 --> 00:14:54,645
...they may be subatomic in size...
227
00:14:54,812 --> 00:14:58,900
...and exist for only fractions of a second
before closing off.
228
00:15:00,234 --> 00:15:04,280
Theoretically, what would it take
to keep a wormhole open...
229
00:15:04,447 --> 00:15:07,325
...and make it big enough
to accommodate a spaceship?
230
00:15:07,492 --> 00:15:10,870
THORNE: It turns out that in order
to hold a wormhole open...
231
00:15:11,037 --> 00:15:14,832
...so it doesn't crunch off and kill you
when you try to go through...
232
00:15:14,999 --> 00:15:21,631
...that you have to have the wormhole threaded
by a negative mass or negative energy.
233
00:15:21,798 --> 00:15:24,008
Einstein says
mass and energy are equivalent.
234
00:15:24,759 --> 00:15:30,139
NARRATOR: Almost all the forms of matter
we know have positive mass and exert gravity.
235
00:15:31,557 --> 00:15:34,018
Negative mass would exert antigravity...
236
00:15:34,185 --> 00:15:37,897
...and repel the walls of a wormhole
to keep it open.
237
00:15:38,064 --> 00:15:43,402
Strangely, it is true
that negative energy can exist...
238
00:15:43,569 --> 00:15:48,116
...and it's been created in the laboratory,
but only in very tiny amounts.
239
00:15:49,075 --> 00:15:50,743
NARRATOR:
It would take vast quantities...
240
00:15:50,910 --> 00:15:54,413
...to prop open a wormhole
large enough for a spaceship.
241
00:15:55,081 --> 00:15:57,583
But just maybe, in the future...
242
00:15:57,750 --> 00:16:02,547
...engineers will devise
advanced technologies to do just that.
243
00:16:02,713 --> 00:16:06,926
Today it's an educated guess,
maybe I should say a half-educated guess...
244
00:16:07,093 --> 00:16:10,429
...that wormholes cannot exist
in our universe...
245
00:16:10,596 --> 00:16:12,598
...but we're far from sure of that.
246
00:16:12,765 --> 00:16:15,643
CARROLL:
The truth is, we just don't know right now.
247
00:16:15,810 --> 00:16:18,563
We don't understand the laws of physics
well enough to say for sure...
248
00:16:18,729 --> 00:16:20,356
...whether or not wormholes are possible.
249
00:16:21,149 --> 00:16:25,862
NARRATOR: But since they're not impossible,
they're fair game for a filmmaker.
250
00:16:26,028 --> 00:16:29,699
I was very excited about the idea
of focusing on a family...
251
00:16:30,032 --> 00:16:31,617
...who would be the pioneers...
252
00:16:31,784 --> 00:16:36,038
...who would experience some of
the extraordinary features of astrophysics...
253
00:16:36,205 --> 00:16:41,085
...particularly the idea of a wormhole
that would allow us to travel to distant stars.
254
00:16:42,795 --> 00:16:45,339
NARRATOR: To create a wormhole
based on real science...
255
00:16:45,506 --> 00:16:48,759
...Visual Effects supervisor Paul Franklin
turned to Kip Thorne.
256
00:16:50,845 --> 00:16:54,473
FRANKLIN: The popular image
of what a wormhole might look like...
257
00:16:54,640 --> 00:16:56,601
...is literally just a hole in space.
258
00:16:56,767 --> 00:17:00,897
It sits on an invisible surface,
you see stuff sliding down the sides...
259
00:17:01,063 --> 00:17:03,232
...and disappearing down the drain,
as it were.
260
00:17:03,399 --> 00:17:05,985
And right in that first conversation,
Kip showed me an image...
261
00:17:06,152 --> 00:17:08,988
...of that kind of classical fantasy image
of these things...
262
00:17:09,155 --> 00:17:13,492
...and said, "This is all wrong."
Ha, ha. "This is not how it is."
263
00:17:13,826 --> 00:17:17,747
NARRATOR: Kip worked out the scientific
equations that define the wormhole...
264
00:17:17,914 --> 00:17:20,458
...and sent them to Paul's animators
back in London.
265
00:17:20,625 --> 00:17:24,420
THORNE: And so for the movie,
I built a mathematical model wormhole...
266
00:17:24,587 --> 00:17:27,965
...based on Einstein's relativity equations.
267
00:17:28,132 --> 00:17:32,845
Paul, Kip and myself, we discussed,
"Okay, we'll visualize the thing.
268
00:17:33,012 --> 00:17:36,015
We'll simulate the thing
exactly as the calculations say."
269
00:17:36,182 --> 00:17:39,060
And Paul Franklin and his team,
they were thrilled to get algorithms...
270
00:17:39,227 --> 00:17:42,688
...that were the absolute latest,
most interesting and up-to-the-minute.
271
00:17:42,855 --> 00:17:44,232
MAN:
Now we can go to the other one.
272
00:17:44,398 --> 00:17:46,817
The wormhole
is a three-dimensional hole in space.
273
00:17:46,984 --> 00:17:49,946
What do you get if you take a circle
and sweep it out in three dimensions?
274
00:17:50,112 --> 00:17:51,364
You get a sphere.
275
00:17:51,530 --> 00:17:55,743
So the wormhole almost feels like
a crystal ball hanging in space.
276
00:17:58,621 --> 00:18:02,333
THORNE: I don't think anybody had ever
really done this kind of visualization before.
277
00:18:02,500 --> 00:18:03,584
This is really unique.
278
00:18:03,751 --> 00:18:08,297
Uh, first time for me,
as well as for you and the audience.
279
00:18:08,464 --> 00:18:09,548
Absolutely, yes.
280
00:18:12,009 --> 00:18:14,929
NARRATOR: In Interstellar, crew members
take a giant leap of faith...
281
00:18:15,096 --> 00:18:17,390
...when they plunge into a wormhole.
282
00:18:17,556 --> 00:18:20,101
DOYLE: You can't think about your family.
You have to think bigger.
283
00:18:20,476 --> 00:18:24,313
COOPER: I am thinking about my family
and millions of other families.
284
00:18:24,480 --> 00:18:27,483
AMELIA: You might have to decide
between seeing your children again...
285
00:18:27,650 --> 00:18:29,277
...and the future of the human race.
286
00:18:29,944 --> 00:18:33,906
NARRATOR: Beyond the wormhole,
the crew will face a far greater challenge:
287
00:18:34,532 --> 00:18:38,286
To navigate the perils of a black hole.
288
00:18:39,954 --> 00:18:43,749
For a filmmaker, that threat
is full of dramatic possibilities.
289
00:18:45,042 --> 00:18:49,630
NOLAN: When you venture out into a story
about a man against the elements...
290
00:18:49,797 --> 00:18:56,387
...visualizing the threat against our protagonist
become very much more exotic.
291
00:18:56,887 --> 00:19:01,976
Deep, deep space gives you
a very, very fresh approach.
292
00:19:02,852 --> 00:19:05,688
NARRATOR: Black holes were predicted
by Einstein's equations...
293
00:19:05,855 --> 00:19:08,649
...but physicists questioned
whether they could really exist.
294
00:19:08,816 --> 00:19:11,319
THORNE:
A black hole is a strange beast.
295
00:19:11,485 --> 00:19:15,031
If this were a black hole,
then instead of a rubber surface...
296
00:19:15,197 --> 00:19:18,409
...it would have a surface
that is made of absolutely nothing...
297
00:19:18,576 --> 00:19:21,245
...except warped space and time.
298
00:19:22,872 --> 00:19:25,541
It's a place where gravity is so strong...
299
00:19:25,708 --> 00:19:29,462
...that if anything falls into the black hole,
it can never get back out.
300
00:19:29,628 --> 00:19:31,964
If you fall in,
you can't send signals back out.
301
00:19:32,131 --> 00:19:34,258
Light can't get out from the interior.
302
00:19:36,052 --> 00:19:38,637
CARROLL: So you might ask,
how would that ever happen?
303
00:19:38,804 --> 00:19:43,434
In outer space, you can get so much mass
together, like in a super-massive star...
304
00:19:43,601 --> 00:19:46,854
...that the gravity just becomes stronger
and stronger and stronger...
305
00:19:47,021 --> 00:19:51,317
...and eventually the pressure
that matter exerts on itself can't keep up.
306
00:19:52,276 --> 00:19:54,904
And everything collapses,
there's a big explosion.
307
00:19:55,071 --> 00:19:59,033
Some of the stuff is blown away,
but the rest of it collapses into a black hole.
308
00:20:00,743 --> 00:20:04,914
NARRATOR: A black hole that spins on its axis
drags the very space around it...
309
00:20:05,081 --> 00:20:09,919
...into a whirling motion
that pulls stars and planets into orbit.
310
00:20:10,086 --> 00:20:14,090
Closer in, gravity increases like a riptide.
311
00:20:14,256 --> 00:20:18,761
At a boundary called the event horizon,
gravity becomes so extreme...
312
00:20:18,928 --> 00:20:22,306
...that nothing can escape being pulled
into the heart of the beast...
313
00:20:22,473 --> 00:20:23,891
...and lost forever.
314
00:20:24,517 --> 00:20:28,354
GHEZ: Black holes are simple,
and yet they have a lot of character.
315
00:20:28,521 --> 00:20:30,523
It's almost like
they can take on personalities.
316
00:20:30,689 --> 00:20:35,027
Um, they can be picky eaters, um,
they can be energetic.
317
00:20:35,194 --> 00:20:36,904
And what you're seeing and describing...
318
00:20:37,071 --> 00:20:39,907
...is really how the black hole
interacts with the environment.
319
00:20:40,866 --> 00:20:43,369
NARRATOR:
UCLA astronomer Andrea Ghez...
320
00:20:43,536 --> 00:20:44,745
Looks like this is Sagi's star.
321
00:20:44,912 --> 00:20:46,872
NARRATOR:
...is an expert on black hole detection.
322
00:20:47,039 --> 00:20:49,041
- Must be this one, right?
- I think it's that one.
323
00:20:49,208 --> 00:20:53,421
NARRATOR: She played a key role investigating
what had long been a scientific hunch.
324
00:20:53,587 --> 00:20:57,007
That a huge black hole
lives at the center of the Milky Way.
325
00:20:57,174 --> 00:20:58,342
It's looking good.
326
00:20:58,509 --> 00:21:01,137
NARRATOR: Astronomers knew
the heart of our galaxy was buzzing...
327
00:21:01,303 --> 00:21:05,141
...with gas, dust and millions of stars.
328
00:21:05,307 --> 00:21:08,644
Some powerful force
appeared to be driving this hubbub.
329
00:21:08,811 --> 00:21:11,188
Could it be a black hole?
330
00:21:12,106 --> 00:21:15,025
Ground telescopes just couldn't produce
sharp images of the region...
331
00:21:16,068 --> 00:21:21,407
...then a technique called adaptive optics
vastly improved the view.
332
00:21:21,574 --> 00:21:25,244
This is what it looks like
before you use advanced technology.
333
00:21:25,744 --> 00:21:26,996
It's a blurry mess...
334
00:21:27,163 --> 00:21:30,833
...and now you can see the individual stars
with adaptive optics turned on.
335
00:21:31,000 --> 00:21:35,129
So each point of light here
is associated with an individual star.
336
00:21:36,589 --> 00:21:41,510
NARRATOR: Andrea put that technique to work
at the Keck Observatory in Hawaii.
337
00:21:42,887 --> 00:21:44,388
GHEZ:
This is a road map.
338
00:21:44,555 --> 00:21:48,184
NARRATOR: And she and her team began
to track the stars at the center of the Milky Way.
339
00:21:48,350 --> 00:21:50,728
GHEZ:
And that's the center of our galaxy.
340
00:21:50,895 --> 00:21:54,064
The very first year that we took the data
was in 1995.
341
00:21:55,107 --> 00:21:59,111
Then we go back to the telescope in '96,
then we take our second image...
342
00:21:59,278 --> 00:22:01,530
...and you have two pictures,
and you can compare them.
343
00:22:03,073 --> 00:22:07,077
NARRATOR: Andrea wanted to see if the stars
were orbiting a single source of gravity...
344
00:22:07,411 --> 00:22:10,206
...but stars can take years
to complete an orbit.
345
00:22:10,831 --> 00:22:13,334
GHEZ: And so it was really important
that we kept going...
346
00:22:13,501 --> 00:22:18,255
...and by 2000 we finally started
to see the star's curve.
347
00:22:18,422 --> 00:22:23,052
In other words, the gravitational influence
of the black hole, um...
348
00:22:23,219 --> 00:22:27,598
...had made those stars
go from straight lines to starting to bend.
349
00:22:27,765 --> 00:22:29,558
Precise enough to see that curvature.
350
00:22:29,725 --> 00:22:34,313
NARRATOR: Year by year,
Andrea and her team built their case.
351
00:22:34,480 --> 00:22:38,567
This animation represents, uh,
20 years of work...
352
00:22:38,734 --> 00:22:45,658
...and it tells you that there is a black hole,
and exactly how massive it is.
353
00:22:45,824 --> 00:22:48,911
NARRATOR: Andrea's painstaking project
revealed a monster...
354
00:22:49,078 --> 00:22:52,331
...with more than 4 million times
the mass of our sun...
355
00:22:52,498 --> 00:22:55,793
...at the center of our Milky Way.
356
00:22:56,418 --> 00:23:00,798
Today, scientists are hunting black holes
with new tools.
357
00:23:00,965 --> 00:23:06,220
Caltech astrophysicist Fiona Harrison
scans the skies with NuSTAR...
358
00:23:06,387 --> 00:23:09,932
...a telescope that looks at the universe
in high-energy x-rays.
359
00:23:11,141 --> 00:23:13,561
HARRISON:
The black hole itself doesn't emit light...
360
00:23:13,727 --> 00:23:16,772
...but dust and gas
falls onto the black holes...
361
00:23:16,939 --> 00:23:22,861
...and in doing so, it heats up,
and it emits x-rays.
362
00:23:23,571 --> 00:23:28,075
NARRATOR: NuSTAR captures black holes
in the process of feasting on matter...
363
00:23:28,242 --> 00:23:31,579
...and the telescope is spotting them
all over the place.
364
00:23:31,954 --> 00:23:36,959
HARRISON: It's really only 10, 20 years ago
that we thought black holes were rare.
365
00:23:37,126 --> 00:23:40,129
We now know that every galaxy,
like our Milky Way...
366
00:23:40,296 --> 00:23:43,090
...has a massive black hole at its heart.
367
00:23:43,591 --> 00:23:48,762
So rather than just being curiosities,
they're actually fundamentally important...
368
00:23:48,929 --> 00:23:51,473
...to why the universe is the way it is.
369
00:23:52,057 --> 00:23:55,561
NARRATOR: So is the Earth at risk
of getting swallowed by a black hole?
370
00:23:56,312 --> 00:23:59,315
HARRISON: Even though we have black holes
sprinkled throughout the galaxy...
371
00:23:59,481 --> 00:24:01,108
...we're in absolutely no danger.
372
00:24:01,275 --> 00:24:05,029
It's a common misconception
that black holes might suck the Earth.
373
00:24:05,195 --> 00:24:08,532
Well, there's no sucking going on,
it's just normal gravity.
374
00:24:09,992 --> 00:24:11,827
It's just when you get very close to it...
375
00:24:11,994 --> 00:24:15,039
...that there's a region
from which light can't even escape...
376
00:24:15,205 --> 00:24:18,042
...and Earth is not gonna do that.
377
00:24:18,917 --> 00:24:20,127
NARRATOR:
But in Interstellar...
378
00:24:20,294 --> 00:24:23,255
...crew members have a precariously close
encounter with a black hole.
379
00:24:23,714 --> 00:24:25,382
COOPER:
Oh, we are not prepared for this.
380
00:24:25,758 --> 00:24:28,385
NARRATOR:
What would the beast look like to them?
381
00:24:28,552 --> 00:24:30,554
One of the things
that Kip was very insistent on...
382
00:24:30,721 --> 00:24:34,433
...is that the black hole, it's spherical,
but it's absolutely black.
383
00:24:34,600 --> 00:24:36,226
It has no surface detail.
384
00:24:36,393 --> 00:24:39,188
Doesn't give shadows
or highlights or anything.
385
00:24:39,355 --> 00:24:42,358
But then early on,
we were talking about accretion disks.
386
00:24:42,775 --> 00:24:47,780
And that gave us a way
to define the spherical shape of the thing.
387
00:24:47,946 --> 00:24:52,326
NARRATOR: A black hole's accretion disk is
made up of gas and dust and magnetic fields...
388
00:24:52,493 --> 00:24:53,911
...that spin at high speeds...
389
00:24:54,411 --> 00:24:56,997
...radiating heat and light.
390
00:24:58,374 --> 00:25:02,419
The black hole's gravity would actually
bend that light like a camera lens...
391
00:25:02,586 --> 00:25:04,338
...in ways that Kip would calculate.
392
00:25:04,797 --> 00:25:09,802
THORNE: I worked out the equations for tracing
light rays traveling around the black hole...
393
00:25:09,968 --> 00:25:15,432
...to see what the disk would look like if you
were in a spacecraft looking at it up close.
394
00:25:15,599 --> 00:25:18,394
NARRATOR: And Paul's team
brought the mathematics to life.
395
00:25:18,560 --> 00:25:22,314
We were really able to use
a very, very accurate representation...
396
00:25:22,481 --> 00:25:26,694
...of the gravitational lens and the effects
of gravity and light around the black hole.
397
00:25:26,860 --> 00:25:32,241
Uh, because what the algorithms gave us
was extremely spectacular.
398
00:25:33,992 --> 00:25:36,245
NARRATOR:
Even Kip was surprised.
399
00:25:36,412 --> 00:25:38,580
You see the disk in front...
400
00:25:38,747 --> 00:25:40,207
...and then when it goes around...
401
00:25:40,374 --> 00:25:44,420
...you see the disk wrap up
around the top of the black hole...
402
00:25:44,586 --> 00:25:46,547
...and wrap around the bottom
of the black hole.
403
00:25:49,717 --> 00:25:51,969
I had guessed
it would look more or less like this...
404
00:25:52,136 --> 00:25:54,763
...but knowing it intellectually
is different than feeling it...
405
00:25:54,930 --> 00:25:57,182
...than absorbing it, than seeing it.
406
00:25:57,850 --> 00:25:59,643
It just blew me away.
407
00:26:00,394 --> 00:26:01,979
NARRATOR:
But this brilliant depiction...
408
00:26:02,146 --> 00:26:05,566
...still can't tell us what happens
in the heart of a black hole...
409
00:26:05,733 --> 00:26:07,484
...beyond the event horizon.
410
00:26:08,902 --> 00:26:14,783
What would happen to an astronaut
daring or crazy enough to dive in feet-first?
411
00:26:14,950 --> 00:26:16,994
THORNE:
In the simplest descriptions of this...
412
00:26:17,161 --> 00:26:20,789
...the descriptions that you will find
in most books that you read...
413
00:26:20,956 --> 00:26:22,916
...you're simply stretched
from head to foot...
414
00:26:23,083 --> 00:26:28,881
...and squeezed from the side by tidal forces,
"spaghettified" is what it often says.
415
00:26:29,381 --> 00:26:32,676
You're spaghettified as you fall in
and you're destroyed.
416
00:26:33,135 --> 00:26:34,970
That's the standard story.
417
00:26:39,600 --> 00:26:42,770
NARRATOR: The truth is,
all the laws of physics that we know...
418
00:26:42,936 --> 00:26:46,190
...break down in the heart of a black hole.
419
00:26:46,356 --> 00:26:50,652
Physicists are still working
on exactly what happens there.
420
00:26:52,070 --> 00:26:53,739
That's the gravity well, though, isn't it?
421
00:26:53,906 --> 00:26:59,119
When we talk to non-physicists,
we will often say it's the gravity well.
422
00:26:59,286 --> 00:27:01,497
So you've been lying to us all these years.
423
00:27:01,663 --> 00:27:04,833
You know how these things go,
there are lies and there are "lies."
424
00:27:05,000 --> 00:27:06,043
I know, but now...
425
00:27:06,460 --> 00:27:11,757
The movie Interstellar deals with physics
that is well-understood, well-established.
426
00:27:11,924 --> 00:27:15,052
It deals with physics
where we make educated guesses...
427
00:27:15,219 --> 00:27:17,930
...and we're almost sure,
but not 100 percent sure of our guesses.
428
00:27:19,056 --> 00:27:22,810
And it deals with physics
at the frontiers of human understanding...
429
00:27:22,976 --> 00:27:24,812
...where we have to speculate...
430
00:27:24,978 --> 00:27:26,814
...and when you get
beyond those frontiers...
431
00:27:26,980 --> 00:27:30,067
...Interstellar works hard to align itself...
432
00:27:30,234 --> 00:27:34,029
...with the best speculations
a scientist could imagine.
433
00:27:34,196 --> 00:27:39,284
We're struggling very hard as filmmakers
to try and explain, uh...
434
00:27:39,451 --> 00:27:42,913
...these scientific concepts,
these sort of abstract ideas...
435
00:27:43,080 --> 00:27:47,209
...in a subjective way and a way that you can
actually experience and feel something about.
436
00:27:48,961 --> 00:27:53,841
NARRATOR: Interstellar mines that gray area
where new ideas percolate...
437
00:27:54,007 --> 00:27:58,887
...and taps deep into questions
about the nature of the universe.
438
00:28:04,393 --> 00:28:08,355
In Interstellar, telescopes on Earth
first detect the presence of a wormhole.
439
00:28:10,065 --> 00:28:14,862
It shows up as a gravitational anomaly
that distorts the view of space.
440
00:28:15,445 --> 00:28:18,782
We made the wormhole
not have all that strong a gravity.
441
00:28:18,949 --> 00:28:20,701
But why the wormhole?
442
00:28:21,076 --> 00:28:24,329
Because then you have a reason
for your trip around it.
443
00:28:24,496 --> 00:28:27,374
I feel uncomfortable with the wormhole
having that much gravity.
444
00:28:27,541 --> 00:28:30,294
THORNE: When I first began working
with Christopher Nolan...
445
00:28:30,460 --> 00:28:33,255
...he wanted a wormhole
that had rather gentle gravity...
446
00:28:33,422 --> 00:28:35,716
...so we discussed
how big the wormhole should be...
447
00:28:35,883 --> 00:28:39,428
...and agreed that it should be
just barely big enough...
448
00:28:39,595 --> 00:28:41,388
...that it could be seen from Earth...
449
00:28:41,555 --> 00:28:44,224
...through the bending of light
around the wormhole...
450
00:28:44,391 --> 00:28:46,560
...by the wormhole's warped space.
451
00:28:46,727 --> 00:28:50,564
NARRATOR: Kip Thorne worked out just
the right gravity for Interstellar's wormhole...
452
00:28:50,981 --> 00:28:55,360
...using equations based on Einstein's theory
of general relativity.
453
00:28:55,527 --> 00:29:01,700
As we've learned, that theory states
that objects warp space-time, creating gravity.
454
00:29:02,534 --> 00:29:06,496
It also predicts that when objects move,
they generate a pulse...
455
00:29:06,663 --> 00:29:10,667
...that propagates through space-time,
a bit like waves through water.
456
00:29:13,629 --> 00:29:18,342
These gravitational waves
have never been directly observed.
457
00:29:18,508 --> 00:29:21,261
They would be small and hard to detect...
458
00:29:21,428 --> 00:29:25,807
...unless they were generated
by a massively violent motion.
459
00:29:27,351 --> 00:29:30,395
Like the birth of the universe.
460
00:29:33,565 --> 00:29:36,443
Physicists developed their big bang theory...
461
00:29:36,610 --> 00:29:41,531
...in part by observing
that today the universe is expanding.
462
00:29:42,741 --> 00:29:48,330
Galaxies are moving away from each other
like raisins in a rising loaf of bread...
463
00:29:48,997 --> 00:29:54,294
...which suggests that in the distant past,
the universe must have been much smaller.
464
00:29:54,461 --> 00:29:59,091
CARROLL: If you wind the movie backwards,
in the past, everything was closer together...
465
00:29:59,257 --> 00:30:04,221
...and you plug that idea
into the equations that Einstein gives us.
466
00:30:04,596 --> 00:30:08,767
And there's a moment, which we now know
was about 14 billion years ago...
467
00:30:08,934 --> 00:30:10,978
...when everything was on top
of everything else...
468
00:30:11,144 --> 00:30:15,816
...when the density of stuff in the universe
was apparently infinitely big.
469
00:30:18,610 --> 00:30:22,906
NARRATOR: Then a powerful force triggered
an expansion of space itself.
470
00:30:23,073 --> 00:30:28,537
Faster than the speed of light,
a theory called cosmic inflation.
471
00:30:28,704 --> 00:30:34,459
And the theory said that this inflation should've
taken fluctuations in the shape of space...
472
00:30:34,626 --> 00:30:37,838
...and amplified them
so they got much stronger.
473
00:30:39,047 --> 00:30:41,383
And they become gravitational waves...
474
00:30:41,550 --> 00:30:45,470
...producing ripples
in the fabric of space and time.
475
00:30:46,638 --> 00:30:48,849
NARRATOR:
If we could detect those ripples today...
476
00:30:49,016 --> 00:30:52,185
...it would help us understand
how the big bang banged.
477
00:30:52,352 --> 00:30:55,063
BOCK: The trick was always
how were we going to measure such a thing.
478
00:30:55,230 --> 00:30:57,107
And that led us to propose and develop...
479
00:30:57,274 --> 00:31:00,152
...this very specialized experiment, um...
480
00:31:00,318 --> 00:31:04,990
...which one of my colleagues
referred to gleefully as a wild-goose chase.
481
00:31:06,199 --> 00:31:10,746
NARRATOR: Caltech physicist Jamie Bock
works in experimental cosmology.
482
00:31:10,912 --> 00:31:14,249
BOCK: Experimental cosmology
is building experiments...
483
00:31:14,416 --> 00:31:16,710
...trying to get back to the dawn of time.
484
00:31:16,877 --> 00:31:17,919
You need a hand with that?
485
00:31:18,086 --> 00:31:19,921
NARRATOR:
The focus of his latest experiment...
486
00:31:20,088 --> 00:31:21,840
...was the oldest light in the universe.
487
00:31:22,174 --> 00:31:26,053
The faint afterglow of the big bang.
488
00:31:26,219 --> 00:31:30,140
Physicists have mapped
this cosmic microwave background...
489
00:31:30,307 --> 00:31:32,517
...across the universe.
490
00:31:33,560 --> 00:31:37,439
If the birth of the universe
produced gravitational waves...
491
00:31:37,606 --> 00:31:39,441
...they would've warped
this primordial light...
492
00:31:39,608 --> 00:31:44,196
...and caused it to be polarized
or curled in a specific direction.
493
00:31:44,362 --> 00:31:46,156
BOCK:
If one could measure the polarization...
494
00:31:46,323 --> 00:31:48,867
...and then not only measure it
but look at its pattern...
495
00:31:49,034 --> 00:31:51,203
...there might be kind of a swirly pattern...
496
00:31:51,369 --> 00:31:54,456
...that would be an indicator
of gravitational waves.
497
00:31:55,999 --> 00:32:00,504
NARRATOR: Jamie and his team designed
a series of small super-sensitive telescopes...
498
00:32:01,630 --> 00:32:04,716
...that they installed
where the skies are crystal clear.
499
00:32:04,883 --> 00:32:06,885
At the South Pole.
500
00:32:07,511 --> 00:32:10,222
BOCK: The South Pole
is the closest we can get to outer space...
501
00:32:10,388 --> 00:32:11,723
...to make our measurements.
502
00:32:14,184 --> 00:32:17,979
NARRATOR: For eight years, the team's
telescopes scanned a patch in the sky...
503
00:32:18,146 --> 00:32:20,607
...measuring minute differences
in the temperature...
504
00:32:20,774 --> 00:32:23,110
...of the cosmic microwave background...
505
00:32:23,276 --> 00:32:24,945
...and a pattern emerged.
506
00:32:25,112 --> 00:32:30,450
BOCK: Our results reported that we see
this swirly pattern of polarization...
507
00:32:30,617 --> 00:32:34,913
...that's consistent with, uh,
what you expect from gravitational waves.
508
00:32:35,705 --> 00:32:39,417
THORNE: So they didn't really see the
gravitational waves from the early universe...
509
00:32:39,584 --> 00:32:43,421
...but they saw this polarization pattern
that was precisely what was predicted...
510
00:32:43,588 --> 00:32:46,091
...except that it was stronger than expected.
511
00:32:46,716 --> 00:32:49,678
Tells us what went on
immediately after the big bang...
512
00:32:49,845 --> 00:32:54,182
...when the universe was a trillionth
of a trillionth of a trillionth of a second old.
513
00:32:54,349 --> 00:32:57,561
So it's seeing almost
the creation of the universe.
514
00:32:58,895 --> 00:33:02,524
NARRATOR: The finding must be confirmed
by other experiments.
515
00:33:02,691 --> 00:33:07,028
If it holds up, this first evidence
for the detection of gravitational waves...
516
00:33:07,195 --> 00:33:11,241
...will deepen our understanding
of the birth of the universe.
517
00:33:12,784 --> 00:33:18,540
And that, by extension,
may help us answer an enduring question:
518
00:33:18,915 --> 00:33:20,876
Can we time travel?
519
00:33:21,042 --> 00:33:23,336
CARROLL:
You know, it's very easy to travel in time.
520
00:33:23,503 --> 00:33:26,548
Yesterday, I've moved forward 24 hours
and here I am.
521
00:33:26,715 --> 00:33:30,093
But that's the only way that it's easy.
It's easy to go into the future.
522
00:33:30,260 --> 00:33:34,514
In fact, it's not just easy, it's inevitable.
We all move into the future over time.
523
00:33:35,265 --> 00:33:38,894
NARRATOR:
But traveling to the past is a different story...
524
00:33:39,227 --> 00:33:42,939
...because space and time
have profoundly different properties.
525
00:33:43,481 --> 00:33:46,735
In space, you can go up, down,
left, right, forward, backward.
526
00:33:48,320 --> 00:33:52,032
NARRATOR: We move freely
through the three dimensions of space.
527
00:33:52,199 --> 00:33:56,953
In time, we experience its one dimension
and a lot less freedom.
528
00:33:57,495 --> 00:34:00,207
CARROLL: Because time has a direction
and space does not.
529
00:34:00,373 --> 00:34:02,209
In time, there's a huge difference...
530
00:34:02,375 --> 00:34:05,545
...between one direction, the future,
and the other direction, the past.
531
00:34:05,712 --> 00:34:09,758
For example, you remember the past,
but you don't remember the future.
532
00:34:09,925 --> 00:34:12,469
You were younger in the past,
we were all younger in the past.
533
00:34:12,636 --> 00:34:15,222
We will all be older. It's all universal to us.
534
00:34:17,891 --> 00:34:21,353
This arrow of time is a little bit mysterious.
535
00:34:21,519 --> 00:34:23,521
We understand the basic underpinnings...
536
00:34:23,688 --> 00:34:27,317
...in a concept called entropy,
the disorderliness of the universe.
537
00:34:28,902 --> 00:34:32,489
NARRATOR: Entropy is the measure
of the disorder in a system.
538
00:34:32,656 --> 00:34:36,034
The more ordered a system,
the lower its entropy.
539
00:34:38,453 --> 00:34:42,207
The more disordered a system,
the higher its entropy.
540
00:34:42,540 --> 00:34:46,962
A classic example of entropy increasing
is just mixing cream into coffee.
541
00:34:47,128 --> 00:34:50,048
When the cream and the coffee are separate,
that's low entropy.
542
00:34:50,215 --> 00:34:52,300
They're organized.
There's the cream, the coffee.
543
00:34:52,467 --> 00:34:55,178
You pour them together,
you let them mix together.
544
00:34:55,512 --> 00:34:58,348
Entropy just goes up.
Things become more and more disorderly.
545
00:35:02,477 --> 00:35:06,147
And this goes all the way back 14 billion years
to the big bang.
546
00:35:07,357 --> 00:35:11,528
NARRATOR: Back then, all the matter in
the universe would have been on top of itself.
547
00:35:11,695 --> 00:35:14,656
Density would have been infinite.
548
00:35:14,823 --> 00:35:17,951
It was the epitome of low entropy.
549
00:35:19,995 --> 00:35:24,165
But entropy has been on the rise
ever since the big bang.
550
00:35:24,541 --> 00:35:27,043
CARROLL: We think, but we haven't
absolutely established...
551
00:35:27,210 --> 00:35:30,922
...that this general tendency
to go from order to disorder...
552
00:35:31,089 --> 00:35:35,218
...is the single reason
why the past is different from the future.
553
00:35:35,385 --> 00:35:39,639
We can't discount in principle
the possibility of visiting the past...
554
00:35:39,806 --> 00:35:43,893
...but all of these weird puzzles
that sort of rub us the wrong way...
555
00:35:44,060 --> 00:35:47,856
...about if I go back into the past
and I give myself a really good idea...
556
00:35:48,023 --> 00:35:51,484
...and then I grow up and become rich off
that idea, where did the idea come from?
557
00:35:51,651 --> 00:35:54,154
These kinds of puzzles would evaporate...
558
00:35:54,321 --> 00:35:57,907
...if we just said, "Well, the laws of physics
don't allow you to visit the past."
559
00:35:58,074 --> 00:36:00,285
So that's probably true.
560
00:36:01,578 --> 00:36:05,749
NARRATOR: To contemplate the mysteries
of space, time and the universe...
561
00:36:05,915 --> 00:36:08,543
...can make a person feel mighty small.
562
00:36:08,710 --> 00:36:13,340
Maybe it's best to lower our sights,
hunker down and focus on planet Earth.
563
00:36:14,382 --> 00:36:18,011
But that's not really an option for humanity
in the long run.
564
00:36:21,556 --> 00:36:25,310
Interstellar depicts a future
where living conditions on Earth are grim.
565
00:36:25,477 --> 00:36:30,231
Our mission does not work if the people
on Earth are dead by the time we pull it off.
566
00:36:30,690 --> 00:36:33,068
NARRATOR:
Failing crops.
567
00:36:33,443 --> 00:36:35,445
Clouds of dust.
568
00:36:37,030 --> 00:36:39,491
Roads clogged with refugees.
569
00:36:39,657 --> 00:36:41,201
Sound familiar?
570
00:36:43,828 --> 00:36:47,290
That's because we've lived
through this scenario before.
571
00:36:48,124 --> 00:36:51,586
In the 1930s, the Great Plains
were hit by extreme drought.
572
00:36:52,379 --> 00:36:55,465
Farmers had plowed up native grasslands.
573
00:36:55,632 --> 00:37:01,012
When crops failed, unprotected topsoil billowed
into clouds that darkened the sky for days.
574
00:37:03,515 --> 00:37:07,852
Some 400,000 people lost nearly everything
during the dust bowl.
575
00:37:08,186 --> 00:37:12,524
One of America's
worst man-made ecological disasters.
576
00:37:15,527 --> 00:37:19,906
It was the model
for the calamity depicted in Interstellar.
577
00:37:21,658 --> 00:37:24,619
NOLAN: I really wanted to try
and bring the audiences' attention...
578
00:37:24,786 --> 00:37:28,039
...to the idea that this
sort of thing really can happen.
579
00:37:28,206 --> 00:37:32,460
And it struck me
that the imagery that you can find...
580
00:37:32,627 --> 00:37:36,005
...was so much more extraordinary than
anything you see in a science fiction film.
581
00:37:36,172 --> 00:37:39,884
And, indeed, in our portrayal of it,
we had to frankly water it down.
582
00:37:40,635 --> 00:37:43,847
NARRATOR: But we'd never let a dust bowl
happen again, would we?
583
00:37:47,350 --> 00:37:52,439
In recent years, cities in the
American Southwest, especially Texas...
584
00:37:52,605 --> 00:37:55,358
...have been battered by huge dust storms.
585
00:37:55,817 --> 00:38:00,113
They've caused fatal traffic accidents
and damaged infrastructure.
586
00:38:00,280 --> 00:38:04,909
The causes are frighteningly familiar
to UCLA geographer Greg Okin...
587
00:38:05,076 --> 00:38:08,538
...an expert on the dynamics
of wind and dust.
588
00:38:09,247 --> 00:38:10,832
OKIN:
We have wind-erodible soil.
589
00:38:10,999 --> 00:38:13,835
We have agriculture
that's disturbed the native vegetation.
590
00:38:14,002 --> 00:38:17,547
We have bare ground because crops fail.
591
00:38:17,714 --> 00:38:19,424
And we have windy conditions.
592
00:38:19,591 --> 00:38:24,596
So all of the same things that happened
in the dust bowl are happening now.
593
00:38:26,222 --> 00:38:29,976
NARRATOR: Models of climate change
predict higher global temperatures.
594
00:38:30,143 --> 00:38:32,687
That probably means more droughts.
595
00:38:33,396 --> 00:38:36,524
Economic pressures may lead
to increased farming of wildlands.
596
00:38:38,526 --> 00:38:42,739
If crops fail due to drought,
that could mean more dust.
597
00:38:43,114 --> 00:38:44,908
OKIN:
It could happen in China.
598
00:38:45,074 --> 00:38:46,618
It could happen in Africa.
599
00:38:46,784 --> 00:38:51,414
Any of these factors, when they're in place,
could cause what we have called the dust bowl.
600
00:38:52,707 --> 00:38:54,375
NARRATOR:
And to make matters worse...
601
00:38:55,043 --> 00:38:59,339
...dust is much dirtier today
than it was in the 1930s.
602
00:38:59,506 --> 00:39:04,219
OKIN: The dust that is interacting
with clouds of pollution from cities...
603
00:39:04,385 --> 00:39:06,846
...in urban and industrial activities, um...
604
00:39:07,013 --> 00:39:12,060
...that actually does appear
to also be more noxious than regular dust.
605
00:39:12,936 --> 00:39:17,565
NARRATOR: Winds blow dust across oceans
and continents and into our lungs.
606
00:39:17,732 --> 00:39:21,444
Dust, particularly for kids with asthma,
is a really big problem.
607
00:39:21,611 --> 00:39:23,530
There's actually quite good evidence...
608
00:39:23,696 --> 00:39:28,785
...for dust being correlated
with pediatric hospital admissions.
609
00:39:28,952 --> 00:39:31,371
That's where the really clear evidence is.
610
00:39:32,664 --> 00:39:35,917
NARRATOR:
No one predicted the dust bowl of the 1930s.
611
00:39:36,084 --> 00:39:38,169
Today, we should know better.
612
00:39:38,336 --> 00:39:41,965
OKIN: We learned the important lesson
that poorly-planned human activity...
613
00:39:42,131 --> 00:39:47,303
...plus unexpected climate variability
can lead to disaster.
614
00:39:47,470 --> 00:39:49,556
There's a lot to worry about.
615
00:39:51,391 --> 00:39:54,644
NARRATOR: Sadly, we don't have a great
track record taking care of Mother Earth.
616
00:39:56,229 --> 00:40:01,359
But the planet is also threatened
by forces far beyond our control.
617
00:40:05,572 --> 00:40:08,116
February 15th, 2013...
618
00:40:10,326 --> 00:40:14,539
...a meteor shining brighter than the sun
streaks across Siberia.
619
00:40:15,206 --> 00:40:18,167
It's a rock 65 feet in diameter...
620
00:40:18,334 --> 00:40:22,213
...and when it explodes in midair,
it releases more than 20 times the energy...
621
00:40:22,380 --> 00:40:25,091
...of the bomb dropped on Hiroshima.
622
00:40:25,717 --> 00:40:27,385
[SCREAMING]
623
00:40:31,347 --> 00:40:35,643
No one was killed,
but more than a thousand people were injured.
624
00:40:37,895 --> 00:40:40,565
Asteroids have struck Earth before.
625
00:40:40,732 --> 00:40:42,567
Some 65 million years ago...
626
00:40:42,942 --> 00:40:47,739
...a monster 6 miles wide
may have wiped out half the species on Earth.
627
00:40:47,905 --> 00:40:50,074
Remember the dinosaurs?
628
00:40:50,241 --> 00:40:53,453
A similar impact, or worse,
could happen any time...
629
00:40:53,953 --> 00:40:57,332
...and turn our blue marble
into a lifeless rock.
630
00:40:59,542 --> 00:41:00,835
And the bottom line?
631
00:41:01,002 --> 00:41:03,963
Earth cannot sustain us forever.
632
00:41:04,756 --> 00:41:08,968
In a few billion years,
our sun will expand as it begins to die...
633
00:41:10,845 --> 00:41:13,640
...and our planet will be toast.
634
00:41:17,268 --> 00:41:18,478
But there's good news.
635
00:41:18,645 --> 00:41:19,979
Unlike the dinosaurs--
636
00:41:20,146 --> 00:41:22,398
MAN: Flight crew, close and lock your visors.
Time to fly.
637
00:41:22,565 --> 00:41:24,233
NARRATOR:
--we can leave Earth.
638
00:41:24,400 --> 00:41:26,944
MAN:
T-minus-10, nine...
639
00:41:27,111 --> 00:41:28,821
Ignition sequence start.
640
00:41:28,988 --> 00:41:33,951
Six, five, four, three, two, one.
641
00:41:34,827 --> 00:41:36,287
Zero.
642
00:41:40,333 --> 00:41:44,212
Zero and liftoff of space shuttle Atlantis.
643
00:41:44,379 --> 00:41:47,715
NARRATOR: Today, nearly 600 people
have traveled to space.
644
00:41:49,550 --> 00:41:54,347
During the shuttle era,
Marsha Ivins made the trip five times.
645
00:41:54,514 --> 00:42:00,311
In order to record all of this, um, we have
created this, uh, wiring nightmare here.
646
00:42:00,478 --> 00:42:05,108
NARRATOR: At Kennedy Space Center Visitor
Complex, she checks in on an old friend.
647
00:42:06,901 --> 00:42:11,823
IVINS: I look at Atlantis hanging here,
it's a surreal kind of experience to think...
648
00:42:12,532 --> 00:42:14,492
...I flew that into space.
649
00:42:14,659 --> 00:42:17,120
It's still something
that I have a hard time believing.
650
00:42:17,286 --> 00:42:18,621
- Hi.
- My name is Tanya.
651
00:42:18,788 --> 00:42:19,997
PHOTOGRAPHER:
One, two, three.
652
00:42:20,164 --> 00:42:24,001
And it makes me feel good
that people still have a wonder...
653
00:42:24,168 --> 00:42:27,797
...and an amazement and a pure joy...
654
00:42:27,964 --> 00:42:31,968
...for the fact that we did fly this vehicle
into space.
655
00:42:32,510 --> 00:42:37,348
NARRATOR: For Marsha,
each mission was as breathtaking as her first.
656
00:42:37,515 --> 00:42:39,600
IVINS:
I looked up overhead...
657
00:42:39,767 --> 00:42:45,982
...and here was this black sky
and this blue Earth.
658
00:42:46,149 --> 00:42:50,653
All hits you at that point,
"I am not on the planet anymore."
659
00:42:51,028 --> 00:42:54,907
And every astronaut who has flown
has come back and said the same thing.
660
00:42:55,074 --> 00:42:56,826
As you circle the Earth...
661
00:42:56,993 --> 00:43:02,707
...you do not see natural borders
and boundaries that separate the countries.
662
00:43:02,874 --> 00:43:08,087
And all of the wars and the angst
and the strife that tear this planet apart...
663
00:43:08,254 --> 00:43:11,132
...seem so insignificant from that view.
664
00:43:12,425 --> 00:43:13,634
NOLAN:
To me...
665
00:43:14,177 --> 00:43:19,849
...space travel, space exploration
has always represented the ultimate frontier.
666
00:43:20,016 --> 00:43:23,895
It's of the absolute extremities
of what human experience is...
667
00:43:24,061 --> 00:43:28,232
...and it's all about trying to, in some way,
define our place in the universe.
668
00:43:28,399 --> 00:43:32,069
MAN: Forty seconds away
from the Apollo 11 liftoff.
669
00:43:32,236 --> 00:43:33,905
JONATHAN:
I remember growing up as a kid...
670
00:43:34,071 --> 00:43:37,950
...and we were both fascinated
by this impulse to flight.
671
00:43:38,117 --> 00:43:44,290
This impulse to build unimaginable machines
and use them to blast off into space.
672
00:43:45,291 --> 00:43:51,088
MAN: Having fired the imagination of
a generation, pulls into port for the last time.
673
00:43:51,255 --> 00:43:54,008
NARRATOR:
The space shuttles were retired in 2011...
674
00:43:54,175 --> 00:43:57,512
...after traveling more than
a half billion miles.
675
00:43:59,931 --> 00:44:03,142
Space exploration demands
enormous resources.
676
00:44:03,309 --> 00:44:06,604
The kind that government agencies
like NASA can marshal.
677
00:44:07,855 --> 00:44:10,650
Recently, some new players entered the fray.
678
00:44:11,692 --> 00:44:14,862
MUSK: I do think we're at the dawn
of a new space era...
679
00:44:15,029 --> 00:44:17,615
...and it's one where commercial companies
play a stronger role.
680
00:44:17,782 --> 00:44:19,325
NASA's not out of the picture.
681
00:44:19,492 --> 00:44:25,206
They're very much in the picture,
but it's not all a NASA-designed system.
682
00:44:26,040 --> 00:44:31,087
NARRATOR: In 2002, Elon Musk started
his own rocket company.
683
00:44:31,254 --> 00:44:34,298
A decade later, under contract to NASA...
684
00:44:34,465 --> 00:44:38,511
...SpaceX became the first private company
in history to carry supplies...
685
00:44:38,678 --> 00:44:41,138
...to and from
the International Space Station.
686
00:44:44,976 --> 00:44:48,688
Now SpaceX is tackling
an even greater challenge.
687
00:44:48,855 --> 00:44:53,401
MUSK: I started SpaceX with the idea
of trying to revolutionize space transport.
688
00:44:53,568 --> 00:44:57,989
And critical to that
is full and rapid reusability of the rocket.
689
00:44:59,323 --> 00:45:02,702
The big issue with rocketry today
is you get one use out of the rocket...
690
00:45:02,869 --> 00:45:07,498
...and then it smashes down into the ocean
or into the plains of Siberia, um...
691
00:45:07,665 --> 00:45:09,375
...and you can't use it again.
692
00:45:10,960 --> 00:45:13,796
If you can, in fact, land the rocket safely...
693
00:45:13,963 --> 00:45:16,591
...and then reuse it
with a minimal amount of effort...
694
00:45:16,757 --> 00:45:22,305
...then you can dramatically
reduce the cost of space transport.
695
00:45:22,471 --> 00:45:27,685
NARRATOR: SpaceX is currently developing
a fully and rapidly reusable launch system.
696
00:45:27,852 --> 00:45:30,646
And that will take Elon closer
to a more ambitious goal:
697
00:45:31,606 --> 00:45:36,402
To help send crews
to establish a colony on Mars.
698
00:45:37,111 --> 00:45:39,822
Not a mission for the fainthearted.
699
00:45:40,489 --> 00:45:42,074
MUSK:
Anyone who wants to go to Mars...
700
00:45:42,241 --> 00:45:47,872
...their desire for adventure would have to
overcome their desire for comfort and safety.
701
00:45:48,873 --> 00:45:53,336
NARRATOR: The colony on Mars
could be the next giant leap for humankind.
702
00:45:53,502 --> 00:45:56,631
NOLAN: It's such a fundamental idea
when you think about it.
703
00:45:56,797 --> 00:46:00,468
It's just a decision that has to be made
in terms of how you view the--
704
00:46:00,635 --> 00:46:02,887
The human race's place in the universe.
705
00:46:03,054 --> 00:46:09,101
We either stay here on Earth or we leave
and we journey through the galaxy.
706
00:46:12,396 --> 00:46:15,191
NARRATOR: To create the look
of the space technology in Interstellar...
707
00:46:15,358 --> 00:46:18,778
...Christopher Nolan
took a clear design approach.
708
00:46:18,945 --> 00:46:22,865
NOLAN: We didn't wanna have anything
that felt purely decorative.
709
00:46:23,032 --> 00:46:26,786
We wanted to approach it
from a more functional point of view...
710
00:46:26,953 --> 00:46:28,913
...just be as convincing as possible...
711
00:46:29,080 --> 00:46:31,707
...looking at the NASA technology
that exists today...
712
00:46:31,874 --> 00:46:34,919
...the International Space Station,
these kind of things as our influences.
713
00:46:36,212 --> 00:46:40,257
NARRATOR: There's no telling how space
technology will evolve in the years to come.
714
00:46:41,217 --> 00:46:46,430
We may be decades away or longer
from establishing a colony on Mars...
715
00:46:46,931 --> 00:46:50,184
...or a permanent habitat
in orbit around the Earth.
716
00:46:50,351 --> 00:46:53,562
But people around the world
are dreaming of that next step.
717
00:46:56,232 --> 00:46:58,901
At a recent space conference...
718
00:46:59,068 --> 00:47:01,070
...NASA and the National Space Society...
719
00:47:01,404 --> 00:47:05,366
...handed out awards
to dozens of forward-looking designs.
720
00:47:07,785 --> 00:47:10,997
A self-sustaining settlement
for 20,000 people.
721
00:47:12,540 --> 00:47:16,460
A moon base that mines minerals
from lunar soil.
722
00:47:17,003 --> 00:47:20,381
A fleet of robots that clean up space junk.
723
00:47:20,548 --> 00:47:23,009
But, of course, this is hard
because we're burning fuel...
724
00:47:23,175 --> 00:47:26,554
NARRATOR: There's not a single PhD
among the prize-winning designers.
725
00:47:26,721 --> 00:47:28,889
[SINGING IN SPANISH]
726
00:47:30,141 --> 00:47:33,477
NARRATOR: These are middle and high school
students from around the world.
727
00:47:33,644 --> 00:47:39,275
What first inspired me was the sky,
the stars, the moon, the planets.
728
00:47:39,442 --> 00:47:44,530
Thinking about going to space
is really exhilarating.
729
00:47:44,697 --> 00:47:48,826
I've always wanted to know, like, what's next?
And for me, space is next.
730
00:47:48,993 --> 00:47:51,245
What we can do is beyond our imagination.
731
00:47:51,620 --> 00:47:57,710
For the survival of the human race,
really, the only option is to go into space.
732
00:47:57,877 --> 00:48:01,589
It should be something that--
A first step we should take as a world.
733
00:48:01,756 --> 00:48:05,134
NARRATOR: One of these kids
may stand on Mars someday...
734
00:48:05,301 --> 00:48:07,511
...or make a breakthrough
in propulsion systems...
735
00:48:08,012 --> 00:48:10,556
...or start a revolution in astrophysics.
736
00:48:11,932 --> 00:48:16,020
To inspire their kind of enthusiasm
is the hope of the Interstellar team.
737
00:48:16,562 --> 00:48:19,023
THOMAS:
I would love for kids to watch Interstellar...
738
00:48:19,190 --> 00:48:23,319
...and get excited about possibilities
of space travel and exploration.
739
00:48:23,652 --> 00:48:28,949
I would hope that this film
introduces many people to science...
740
00:48:29,116 --> 00:48:32,870
...who might not have gotten curious
about this kind of science in any other way.
741
00:48:33,037 --> 00:48:36,707
I think it would be really thrilling
if people got some sense from this film...
742
00:48:36,874 --> 00:48:39,502
...that, uh, these ideas
are worth thinking about.
743
00:48:42,213 --> 00:48:44,965
NARRATOR: The interplay between science
and science fiction...
744
00:48:45,132 --> 00:48:47,760
...springs from a
deep-seated creative drive.
745
00:48:51,263 --> 00:48:52,598
To make sense of the unknown.
746
00:49:01,107 --> 00:49:02,691
To engineer new worlds.
747
00:49:07,780 --> 00:49:09,532
To dream up a better future.
748
00:49:10,783 --> 00:49:14,203
We'll find answers where we always have:
749
00:49:14,870 --> 00:49:17,456
Just beyond the next horizon.
71446
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.