Would you like to inspect the original subtitles? These are the user uploaded subtitles that are being translated:
1
00:00:02,435 --> 00:00:04,437
ZACHARY QUINTO:
A billion miles from the sun...
2
00:00:04,471 --> 00:00:05,538
(rocks thudding)
3
00:00:05,572 --> 00:00:11,211
Past Mars and Jupiter...
4
00:00:13,546 --> 00:00:16,149
A planet like no other.
5
00:00:16,182 --> 00:00:19,019
MICHELE DOUGHERTY:
All you can see is
this beautiful vision
6
00:00:19,052 --> 00:00:20,019
of the rings around it.
7
00:00:20,053 --> 00:00:21,454
♪
8
00:00:21,488 --> 00:00:24,290
QUINTO:
Saturn.
9
00:00:24,324 --> 00:00:26,559
Of all the distant worlds...
10
00:00:26,593 --> 00:00:29,629
EDGARD RIVERA-VALENTIN:
Saturn is very weird.
11
00:00:29,662 --> 00:00:32,165
Every time we think
we have Saturn pegged,
12
00:00:32,198 --> 00:00:34,067
we get another piece of evidence
that tells us,
13
00:00:34,100 --> 00:00:35,201
no, everything we thought
was wrong.
14
00:00:35,235 --> 00:00:36,569
(wind whipping)
15
00:00:36,603 --> 00:00:40,373
QUINTO:
...it's the most mysterious
and alluring.
16
00:00:40,407 --> 00:00:41,541
(lightning crashes)
17
00:00:41,574 --> 00:00:42,976
♪
18
00:00:43,009 --> 00:00:44,577
It's just a puzzle
you want to solve.
19
00:00:45,879 --> 00:00:48,982
QUINTO:
We've visited three times.
20
00:00:49,015 --> 00:00:53,353
Pioneer and Voyager offered
a passing glimpse.
21
00:00:53,386 --> 00:00:54,921
We started taking pictures
several weeks out.
22
00:00:54,954 --> 00:01:00,226
CAROLYN PORCO:
It's a frenzied period
of lots of activity
23
00:01:00,260 --> 00:01:01,728
and sleepless nights
24
00:01:01,761 --> 00:01:04,330
and discovery and conquest.
25
00:01:04,364 --> 00:01:05,632
And then it's all over.
26
00:01:05,665 --> 00:01:10,136
QUINTO:
But Cassini came to stay...
27
00:01:10,170 --> 00:01:11,504
And what a wonderland we found.
28
00:01:11,538 --> 00:01:13,206
QUINTO:
...and to astonish.
29
00:01:13,239 --> 00:01:14,307
(thunder rumbles)
30
00:01:14,340 --> 00:01:16,042
KEVIN BAINES:
We found water ice,
31
00:01:16,076 --> 00:01:17,544
and that basically blew
our minds.
32
00:01:17,577 --> 00:01:19,579
♪
33
00:01:19,612 --> 00:01:23,216
PORCO:
Just right out of the gate,
we saw vertical structures.
34
00:01:23,249 --> 00:01:25,018
♪
35
00:01:25,051 --> 00:01:28,054
We just lacked the imagination
that it would require
36
00:01:28,088 --> 00:01:29,456
to predict
what it would look like.
37
00:01:29,489 --> 00:01:30,990
♪
38
00:01:31,024 --> 00:01:34,494
JONATHAN LUNINE:
I think that Enceladus
may be the first place
39
00:01:34,527 --> 00:01:37,363
where we will discover a form
of life
40
00:01:37,397 --> 00:01:40,166
that's independent from life
on the Earth.
41
00:01:40,200 --> 00:01:43,303
QUINTO:
And in the end
a heartbreaking choice
42
00:01:43,336 --> 00:01:44,537
to save a world.
43
00:01:44,571 --> 00:01:45,939
♪
44
00:01:45,972 --> 00:01:48,508
JULIE WEBSTER:
I was supposed to call
end of mission.
45
00:01:48,541 --> 00:01:50,743
I couldn't get the words out.
46
00:01:52,112 --> 00:01:53,646
It's still hard.
47
00:01:55,181 --> 00:01:56,549
♪
48
00:01:56,583 --> 00:01:58,985
QUINTO:
"The Planets: Saturn."
49
00:01:59,018 --> 00:02:01,154
Right now, on "NOVA."
50
00:02:02,522 --> 00:02:06,993
♪
51
00:02:08,828 --> 00:02:20,640
Major funding for "NOVA"
is provided by the following:
52
00:02:21,641 --> 00:02:23,209
("The Void" by Muse playing)
53
00:02:23,243 --> 00:02:31,150
♪ They'll say
no one can see us ♪
54
00:02:31,184 --> 00:02:37,123
♪ That we're estranged
and all alone ♪
55
00:02:37,156 --> 00:02:43,830
♪ They believe
nothing can reach us ♪
56
00:02:43,863 --> 00:02:52,372
♪ And pull us out
of the boundless gloom ♪
57
00:02:52,405 --> 00:02:55,842
♪ They're wrong
58
00:02:55,875 --> 00:02:58,511
♪ They're wrong
59
00:02:58,545 --> 00:03:03,016
♪ They're wrong
60
00:03:07,587 --> 00:03:09,923
("The Void" ends)
61
00:03:13,159 --> 00:03:17,263
♪
62
00:03:21,701 --> 00:03:25,805
QUINTO:
Beyond the warm worlds
of the inner solar system...
63
00:03:30,710 --> 00:03:34,013
...beyond the gas giant Jupiter,
64
00:03:34,047 --> 00:03:39,152
in the freezing region
far beyond the sun...
65
00:03:39,185 --> 00:03:41,454
♪
66
00:03:41,487 --> 00:03:43,523
lies Saturn...
67
00:03:43,556 --> 00:03:50,463
♪
68
00:03:50,496 --> 00:03:52,832
a planet made unique
69
00:03:52,865 --> 00:03:56,869
thanks to a nearly
45,000-mile-wide ring
70
00:03:56,903 --> 00:03:58,404
of frozen water.
71
00:03:58,438 --> 00:04:03,309
♪
72
00:04:08,915 --> 00:04:12,919
Here, trillions of pieces of ice
have been sculpted
73
00:04:12,952 --> 00:04:14,454
by gravitational forces
74
00:04:14,487 --> 00:04:19,125
into some of the solar system's
most stunning vistas.
75
00:04:19,158 --> 00:04:23,296
♪
76
00:04:35,541 --> 00:04:38,378
Even from nearly
a billion miles away,
77
00:04:38,411 --> 00:04:41,981
this planet inspires.
78
00:04:42,015 --> 00:04:45,218
PORCO:
We were about,
13 or 14 years old,
79
00:04:45,251 --> 00:04:47,387
you know, just tootling around
trying to find, you know,
80
00:04:47,420 --> 00:04:48,688
this and that,
and then we saw Saturn,
81
00:04:48,721 --> 00:04:54,727
and it's just so alien
and mysterious-looking.
82
00:04:54,761 --> 00:04:55,928
All you can see is
83
00:04:55,962 --> 00:04:58,331
this beautiful vision
of the rings around it.
84
00:04:58,364 --> 00:05:02,135
It's a thin, flat disc
touching nowhere, you know?
85
00:05:02,168 --> 00:05:04,837
It's, they're just fascinating.
and you just can't help
86
00:05:04,871 --> 00:05:07,173
but wonder
what causes that structure.
87
00:05:09,776 --> 00:05:11,778
Saturn is very weird.
88
00:05:11,811 --> 00:05:14,914
Every time we think
we have Saturn pegged,
89
00:05:14,947 --> 00:05:16,683
we get another piece of evidence
that tells us
90
00:05:16,716 --> 00:05:17,817
no, everything
we thought was wrong.
91
00:05:17,850 --> 00:05:22,021
♪
92
00:05:22,055 --> 00:05:24,557
QUINTO:
Saturn is a planet of mysteries.
93
00:05:24,590 --> 00:05:29,195
(humming,
electricity crackling)
94
00:05:29,228 --> 00:05:32,999
Why did this world become
so large?
95
00:05:33,032 --> 00:05:36,803
What drives its strange weather?
96
00:05:36,836 --> 00:05:40,940
And where did its beautiful,
bright rings come from?
97
00:05:40,973 --> 00:05:45,344
♪
98
00:05:51,884 --> 00:05:54,620
Today our probes are beginning
to shed light
99
00:05:54,654 --> 00:05:57,357
on these questions,
100
00:05:57,390 --> 00:06:01,961
making discoveries which hint
that Saturn's true beauty
101
00:06:01,994 --> 00:06:04,497
lies beyond its rings,
102
00:06:04,530 --> 00:06:08,701
hidden within
its extraordinary moons.
103
00:06:08,735 --> 00:06:11,170
PORCO:
We now have
what I consider to be
104
00:06:11,204 --> 00:06:16,008
the most promising place to go
look for life.
105
00:06:16,042 --> 00:06:17,143
Will we find life if we go back?
106
00:06:17,176 --> 00:06:18,444
I don't know.
107
00:06:18,478 --> 00:06:21,247
Nobody knows.
108
00:06:21,280 --> 00:06:22,749
But we want to try.
109
00:06:24,884 --> 00:06:28,588
(wind blowing, thunder rumbling)
110
00:06:30,022 --> 00:06:32,425
(lightning crashes)
111
00:06:32,458 --> 00:06:36,062
♪
112
00:06:39,398 --> 00:06:44,337
QUINTO:
Picture a place with no surface
on which to stand...
113
00:06:44,370 --> 00:06:48,775
(thunder rumbling)
114
00:06:48,808 --> 00:06:51,210
only endless atmosphere.
115
00:06:51,244 --> 00:06:54,447
(crackling, rumbling)
116
00:06:57,383 --> 00:07:00,820
♪
117
00:07:00,853 --> 00:07:04,323
Compared to Earth,
Saturn is so alien
118
00:07:04,357 --> 00:07:06,726
that it's hard to imagine
how it could have grown
119
00:07:06,759 --> 00:07:11,230
from the same ingredients.
120
00:07:11,264 --> 00:07:16,836
So how did this incredible,
mysterious planet come to be?
121
00:07:16,869 --> 00:07:20,173
♪
122
00:07:24,377 --> 00:07:28,481
♪
123
00:07:35,254 --> 00:07:39,125
Saturn begins
as a tiny, ragged world,
124
00:07:39,158 --> 00:07:42,461
tumbling chaotically
through space.
125
00:07:42,495 --> 00:07:45,264
♪
126
00:07:45,298 --> 00:07:47,567
Just like
the inner, rocky worlds,
127
00:07:47,600 --> 00:07:51,671
it clumps together
with other objects to grow.
128
00:07:51,704 --> 00:07:54,740
But there is
a crucial difference.
129
00:07:54,774 --> 00:07:58,044
Saturn is forming far
from the sun.
130
00:07:58,077 --> 00:08:02,148
(rocks thudding)
131
00:08:02,181 --> 00:08:04,016
Among the planets
in the solar system,
132
00:08:04,050 --> 00:08:06,986
Saturn and Jupiter were two
of the first ones to form.
133
00:08:08,254 --> 00:08:11,524
They formed at a very unique
place in the solar system,
134
00:08:11,557 --> 00:08:13,826
what is known as the snow line.
135
00:08:13,860 --> 00:08:16,662
LEIGH FLETCHER:
Now, the snow line is
the location
136
00:08:16,696 --> 00:08:19,832
at which the temperature
of the original solar nebula
137
00:08:19,866 --> 00:08:23,102
got cold enough for ice to form.
138
00:08:23,135 --> 00:08:25,671
And that ice then goes on
to form the building blocks
139
00:08:25,705 --> 00:08:30,643
for the larger planets
that are present further out.
140
00:08:30,676 --> 00:08:35,515
LUNINE:
Now, what that snow line does is
it puts a large amount
141
00:08:35,548 --> 00:08:39,752
of additional solid material
into this disc.
142
00:08:39,785 --> 00:08:42,054
(thudding)
143
00:08:42,088 --> 00:08:45,658
And so that would accelerate
the growth of the giant planet,
144
00:08:45,691 --> 00:08:49,295
so it would allow them
to form their cores more quickly
145
00:08:49,328 --> 00:08:51,264
than if only rock were present.
146
00:08:51,297 --> 00:08:55,835
♪
147
00:08:57,436 --> 00:09:01,474
QUINTO:
As the infant Saturn sweeps
through its orbit,
148
00:09:01,507 --> 00:09:04,544
it's able to scoop up huge
amounts of extra frozen matter
149
00:09:04,577 --> 00:09:08,247
unavailable to the worlds
of the inner solar system.
150
00:09:08,281 --> 00:09:12,985
(rock rumbling, crashing)
151
00:09:13,019 --> 00:09:15,388
Under the force of gravity,
152
00:09:15,421 --> 00:09:19,191
this abundant ice
and rock collides and combines,
153
00:09:19,225 --> 00:09:21,994
♪
154
00:09:22,028 --> 00:09:26,699
helping the young Saturn grow
into a giant.
155
00:09:26,732 --> 00:09:30,870
♪
156
00:09:36,409 --> 00:09:39,345
Just a few million years
after its birth,
157
00:09:39,378 --> 00:09:44,116
Saturn has formed into
a great ball of rock and ice.
158
00:09:45,751 --> 00:09:48,988
So how did this world become
the giant planet of gas
159
00:09:49,021 --> 00:09:51,457
we know today?
160
00:09:51,490 --> 00:09:54,660
The clues to what happened next
would be revealed
161
00:09:54,694 --> 00:09:58,030
by one of the most ambitious
deep-space missions
162
00:09:58,064 --> 00:09:59,298
ever attempted.
163
00:10:01,167 --> 00:10:04,236
(rocket engine igniting)
164
00:10:07,473 --> 00:10:11,744
♪
165
00:10:24,523 --> 00:10:29,095
The Voyager probes are two
almost identical spacecraft
166
00:10:29,128 --> 00:10:32,898
built to explore the
solar system's distant worlds.
167
00:10:32,932 --> 00:10:35,468
♪
168
00:10:42,708 --> 00:10:46,345
PORCO:
Voyager was unlike anything
that had come before.
169
00:10:46,379 --> 00:10:50,416
It was a long-duration,
tricky, uncertain journey
170
00:10:50,449 --> 00:10:54,053
across the solar system
and beyond.
171
00:10:57,156 --> 00:11:01,727
♪
172
00:11:04,530 --> 00:11:06,665
We started taking pictures
several weeks out,
173
00:11:06,699 --> 00:11:10,369
and Saturn just grew larger
and larger in those images
174
00:11:10,403 --> 00:11:13,372
and more and more detail.
175
00:11:13,406 --> 00:11:15,007
I remember getting down to JPL,
176
00:11:15,041 --> 00:11:17,176
and the whole place was full
177
00:11:17,209 --> 00:11:19,645
of all these big RVs
from all the TV networks,
178
00:11:19,679 --> 00:11:22,081
and I was amazed that
there was all this interest.
179
00:11:22,114 --> 00:11:24,984
So I got in, and
people showed me these images,
180
00:11:25,017 --> 00:11:26,185
and they were just spectacular.
181
00:11:26,218 --> 00:11:30,356
♪
182
00:11:35,127 --> 00:11:36,829
LINDA SPILKER:
You could start to see evidence
183
00:11:36,862 --> 00:11:39,532
of the banded structure
around Saturn.
184
00:11:39,565 --> 00:11:41,434
You could start to see detail
in the rings,
185
00:11:41,467 --> 00:11:45,271
and it was just sort of like
watching this zoom in
186
00:11:45,304 --> 00:11:46,439
to see Saturn.
187
00:11:46,472 --> 00:11:49,175
♪
188
00:11:49,208 --> 00:11:53,646
JEFF CUZZI:
They're all these ringlets and
structure and bright and dark,
189
00:11:53,679 --> 00:11:54,747
beautiful, beautiful sight.
190
00:11:54,780 --> 00:11:58,350
(whirring)
191
00:11:58,384 --> 00:12:02,521
♪
192
00:12:02,555 --> 00:12:05,091
CARL SAGAN:
Just an amazing harvest
of pictures,
193
00:12:05,124 --> 00:12:07,059
you know, there's tens of
thousands of photographs
194
00:12:07,093 --> 00:12:09,428
of Saturn and its rings
and its moons
195
00:12:09,462 --> 00:12:11,297
taken by the Voyager 2
spacecraft.
196
00:12:11,330 --> 00:12:14,567
♪
197
00:12:14,600 --> 00:12:16,035
PORCO:
It's a frenzied
198
00:12:16,068 --> 00:12:18,938
period of lots of activity
199
00:12:18,971 --> 00:12:23,909
and sleepless nights
and, and discovery and conquest,
200
00:12:23,943 --> 00:12:25,010
and then it's all over.
201
00:12:25,044 --> 00:12:28,180
♪
202
00:12:35,821 --> 00:12:38,591
QUINTO:
The Voyager probes
completely transform
203
00:12:38,624 --> 00:12:40,793
our understanding of Saturn...
204
00:12:42,895 --> 00:12:44,363
showing in great detail
205
00:12:44,396 --> 00:12:48,767
the composition
of the upper atmosphere,
206
00:12:48,801 --> 00:12:52,705
almost all of it made
of helium and hydrogen...
207
00:12:52,738 --> 00:12:55,007
♪
208
00:12:55,040 --> 00:12:59,078
the very same gasses abundant
in the early solar system.
209
00:13:01,480 --> 00:13:02,615
It's critical evidence
210
00:13:02,648 --> 00:13:04,750
in piecing together
Saturn's story...
211
00:13:07,386 --> 00:13:10,923
and its evolution
from a rocky world.
212
00:13:17,363 --> 00:13:21,500
♪
213
00:13:28,541 --> 00:13:32,811
Just a few million years
after the formation of the sun,
214
00:13:32,845 --> 00:13:38,484
Saturn is beginning
a radical transformation.
215
00:13:38,517 --> 00:13:40,219
Many times more massive
216
00:13:40,252 --> 00:13:42,087
than the worlds
of the inner solar system...
217
00:13:42,121 --> 00:13:44,924
♪
218
00:13:44,957 --> 00:13:46,992
its gravity is powerful enough
219
00:13:47,026 --> 00:13:50,663
to draw in hydrogen
and helium gas.
220
00:13:50,696 --> 00:13:56,068
♪
221
00:13:56,101 --> 00:13:58,437
LUNINE:
Saturn got a large core,
222
00:13:58,470 --> 00:14:01,473
perhaps 20 times
the mass of the Earth,
223
00:14:01,507 --> 00:14:04,243
that was large enough to cause
all of that of hydrogen
224
00:14:04,276 --> 00:14:08,247
and helium gas around it
to collapse onto the core.
225
00:14:08,280 --> 00:14:09,648
It had enough gravity then
226
00:14:09,682 --> 00:14:12,151
to pull in a lot
of the other gases,
227
00:14:12,184 --> 00:14:15,187
and from that,
to grow this huge,
228
00:14:15,221 --> 00:14:17,990
what we call gas-giant planet.
229
00:14:18,023 --> 00:14:22,161
♪
230
00:14:24,964 --> 00:14:27,333
BAINES:
When you get to a certain size,
then you start grabbing
231
00:14:27,366 --> 00:14:29,435
onto these clouds of water
and hydrogen and helium
232
00:14:29,468 --> 00:14:30,836
that are still hanging around.
233
00:14:30,869 --> 00:14:32,037
It's a runaway effect.
234
00:14:32,071 --> 00:14:33,439
Once you grow a little bit,
235
00:14:33,472 --> 00:14:35,641
now you're going to expand
really fast.
236
00:14:35,674 --> 00:14:38,744
So that's how you grow from
a small, relatively small body
237
00:14:38,777 --> 00:14:40,412
to a huge body
in only a few million years.
238
00:14:40,446 --> 00:14:45,551
♪
239
00:14:45,584 --> 00:14:49,288
QUINTO:
Just a few hundred million years
after its birth,
240
00:14:49,321 --> 00:14:52,992
Saturn is now vast,
241
00:14:53,025 --> 00:14:58,130
so big, it could contain
5,000 Earth-sized worlds.
242
00:14:59,431 --> 00:15:04,637
Over time this gas will compress
and condense,
243
00:15:04,670 --> 00:15:07,206
eventually becoming
the second-largest planet
244
00:15:07,239 --> 00:15:10,342
in the solar system.
245
00:15:10,376 --> 00:15:14,346
♪
246
00:15:22,254 --> 00:15:26,925
The Voyager probes reveal some
of the mysteries of Saturn,
247
00:15:26,959 --> 00:15:31,730
but they raise more questions
than they answer.
248
00:15:31,764 --> 00:15:37,202
What is happening beneath
Saturn's strange, hazy exterior?
249
00:15:37,236 --> 00:15:41,640
Does the planet still have
a rocky core?
250
00:15:41,674 --> 00:15:44,076
And what is powering
the massive storms
251
00:15:44,109 --> 00:15:46,679
swirling across its surface?
252
00:15:46,712 --> 00:15:49,748
♪
253
00:15:49,782 --> 00:15:51,617
PORCO:
After Voyager was over,
254
00:15:51,650 --> 00:15:55,621
all of us were just really eager
to go back,
255
00:15:55,654 --> 00:15:57,389
because everything we saw,
256
00:15:57,423 --> 00:15:59,591
we just, you know,
we just skimmed the top,
257
00:15:59,625 --> 00:16:00,893
we didn't have time to delve
into.
258
00:16:00,926 --> 00:16:04,563
♪
259
00:16:08,267 --> 00:16:14,306
QUINTO:
Just a few years
after Voyager's flyby,
260
00:16:14,340 --> 00:16:16,742
planning begins on a new probe
loaded with instruments
261
00:16:16,775 --> 00:16:22,314
to uncover Saturn's secrets.
262
00:16:22,348 --> 00:16:26,085
Building a craft like this
is a huge challenge.
263
00:16:27,353 --> 00:16:28,887
DOUGHERTY:
It's difficult to put a number
264
00:16:28,921 --> 00:16:31,657
on how many people were involved
in Cassini,
265
00:16:31,690 --> 00:16:34,827
um...
tens of thousands, I would say.
266
00:16:34,860 --> 00:16:39,064
♪
267
00:16:42,634 --> 00:16:48,407
There's over ten miles of wiring
in the main harness alone.
268
00:16:48,440 --> 00:16:50,309
And you have to check out
every wire.
269
00:16:50,342 --> 00:16:54,146
This is a very, very
complex effort,
270
00:16:54,179 --> 00:16:57,683
so it took us
two-and-a-half years
271
00:16:57,716 --> 00:16:59,218
to put the thing together.
272
00:16:59,251 --> 00:17:04,590
♪
273
00:17:11,463 --> 00:17:13,565
PORCO:
All of us spent a lot of effort
274
00:17:13,599 --> 00:17:15,734
to get to that moment, uh,
275
00:17:15,768 --> 00:17:18,237
so there's a lot of emotion
attached to it.
276
00:17:18,270 --> 00:17:19,304
(rocket ignites)
277
00:17:19,338 --> 00:17:22,141
And then you see it launch,
and you know
278
00:17:22,174 --> 00:17:26,779
that it's on a journey
to a very, very distant place.
279
00:17:26,812 --> 00:17:29,047
And so you feel
like you're going too.
280
00:17:29,081 --> 00:17:31,383
♪
281
00:17:31,417 --> 00:17:33,519
QUINTO:
Cassini is one of the
heaviest interplanetary probes
282
00:17:33,552 --> 00:17:35,020
ever launched,
283
00:17:35,053 --> 00:17:39,591
weighing in at over six tons.
284
00:17:39,625 --> 00:17:46,031
But its huge size complicates
its route to Saturn.
285
00:17:46,064 --> 00:17:49,168
To be able to launch a
spacecraft as large as Cassini
286
00:17:49,201 --> 00:17:50,702
with enough fuel to be able
287
00:17:50,736 --> 00:17:55,107
to do exciting science out
at Saturn,
288
00:17:55,140 --> 00:17:57,910
you can't use all that fuel up
in getting out to Saturn.
289
00:17:57,943 --> 00:18:00,612
And so what is done is
290
00:18:00,646 --> 00:18:05,484
we use flybys past
other planets.
291
00:18:05,517 --> 00:18:06,919
(hissing, small explosion)
292
00:18:08,620 --> 00:18:11,423
It's almost like
two sort of billiard balls--
293
00:18:11,457 --> 00:18:13,725
if the moving one bumps
into the stationary one,
294
00:18:13,759 --> 00:18:15,394
it gives the stationary one
a bit of energy.
295
00:18:15,427 --> 00:18:16,662
So it's an exchange of energy.
296
00:18:16,695 --> 00:18:18,897
♪
297
00:18:18,931 --> 00:18:22,634
The spacecraft is flown
really close to a planet,
298
00:18:22,668 --> 00:18:23,969
gets a bit of a kick,
299
00:18:24,002 --> 00:18:27,139
and gets kicked out
onto the next one.
300
00:18:27,172 --> 00:18:32,478
QUINTO:
The journey to Saturn will
require two trips past Venus,
301
00:18:32,511 --> 00:18:34,913
one past Earth,
302
00:18:34,947 --> 00:18:39,318
and finally a speed boost
from Jupiter.
303
00:18:39,351 --> 00:18:41,987
These maneuvers help Cassini
reach speeds
304
00:18:42,020 --> 00:18:46,158
of over 60,000 miles per hour.
305
00:18:46,191 --> 00:18:51,697
But the probe's most difficult
moment is yet to come.
306
00:18:51,730 --> 00:18:53,899
CUZZI:
The one critical sequence,
307
00:18:53,932 --> 00:18:55,701
going into orbit around Saturn.
308
00:18:55,734 --> 00:19:01,440
♪
309
00:19:01,473 --> 00:19:02,774
You can get there,
310
00:19:02,808 --> 00:19:04,977
you throw a rock,
and the rock flies,
311
00:19:05,010 --> 00:19:07,112
but when we get there,
we have to stop.
312
00:19:07,146 --> 00:19:10,449
So we had to fire the rocket
at exactly the right time...
313
00:19:11,750 --> 00:19:13,218
in exactly the right direction
314
00:19:13,252 --> 00:19:15,954
for exactly
the right amount of time,
315
00:19:15,988 --> 00:19:18,190
or after all that planning,
we just go right by.
316
00:19:18,223 --> 00:19:19,858
♪
317
00:19:19,892 --> 00:19:23,629
WEBSTER:
The time to get data from Saturn
to the Earth is 90 minutes.
318
00:19:23,662 --> 00:19:25,531
So if you send a command
to the spacecraft,
319
00:19:25,564 --> 00:19:27,232
it takes 90 minutes to get
out there,
320
00:19:27,266 --> 00:19:28,433
lets the command work it,
321
00:19:28,467 --> 00:19:30,602
and then it takes 90 minutes
to get back.
322
00:19:30,636 --> 00:19:32,237
Until you get there,
323
00:19:32,271 --> 00:19:34,573
there's always this chance
in your mind
324
00:19:34,606 --> 00:19:38,777
that something's not right.
325
00:19:38,810 --> 00:19:40,212
MAN (on radio):
The Doppler has flattened out.
326
00:19:40,245 --> 00:19:42,114
(cheers and applause)
327
00:19:42,147 --> 00:19:45,484
WEBSTER:
So there was a great deal
of relief.
328
00:19:45,517 --> 00:19:46,919
(cheers, laughter)
329
00:19:54,793 --> 00:19:57,129
QUINTO:
When Cassini arrives,
330
00:19:57,162 --> 00:20:01,667
the images it sends back
to Earth are breathtaking.
331
00:20:01,700 --> 00:20:04,269
CUZZI:
I was sitting
in what they call the blue room
332
00:20:04,303 --> 00:20:08,140
being interviewed while they
were beaming for the first time,
333
00:20:08,173 --> 00:20:09,675
and then one of these pictures
came on,
334
00:20:09,708 --> 00:20:11,376
and I just went,
"Wow, look at that."
335
00:20:11,410 --> 00:20:13,145
♪
336
00:20:13,178 --> 00:20:14,279
That was really
337
00:20:14,313 --> 00:20:18,250
the jumping-out-of-the-chair
moment for me,
338
00:20:18,283 --> 00:20:19,585
and it was just the first day.
339
00:20:19,618 --> 00:20:23,255
♪
340
00:20:23,288 --> 00:20:25,157
CARL MURRAY:
What we were seeing was
the highest resolution
341
00:20:25,190 --> 00:20:28,126
that had ever been seen.
342
00:20:28,160 --> 00:20:30,495
I saw phenomena
that I'd only seen
343
00:20:30,529 --> 00:20:32,831
in kind of computer simulations
before,
344
00:20:32,864 --> 00:20:35,567
and now I was seeing it
for the first time, um,
345
00:20:35,601 --> 00:20:37,536
and realizing all,
all this was real.
346
00:20:37,569 --> 00:20:39,871
♪
347
00:20:39,905 --> 00:20:42,874
PORCO:
And we were seeing details
in the rings
348
00:20:42,908 --> 00:20:46,712
that were shocking, shocking.
349
00:20:46,745 --> 00:20:51,383
We just lacked the imagination
that it would require
350
00:20:51,416 --> 00:20:55,187
to predict
what it would look like.
351
00:20:55,220 --> 00:20:57,556
♪
352
00:20:57,589 --> 00:21:00,959
QUINTO:
Thanks to
Cassini's powerful instruments,
353
00:21:00,993 --> 00:21:03,996
Saturn's billion-year-old
mysteries
354
00:21:04,029 --> 00:21:05,931
start to become clearer.
355
00:21:09,167 --> 00:21:11,903
(low humming)
356
00:21:11,937 --> 00:21:15,274
Peering into
Saturn's tumultuous atmosphere
357
00:21:15,307 --> 00:21:19,711
produces new insights about
the planet's distant past.
358
00:21:19,745 --> 00:21:22,114
♪
359
00:21:22,147 --> 00:21:27,786
One of the biggest questions is
what lies within the clouds.
360
00:21:27,819 --> 00:21:30,355
BAINES:
You see clouds of different
things floating around,
361
00:21:30,389 --> 00:21:31,823
but what are
those clouds made out of?
362
00:21:31,857 --> 00:21:35,761
We didn't really know
until we got there with Cassini.
363
00:21:35,794 --> 00:21:38,597
Some of the clouds actually are
made of water ice.
364
00:21:38,630 --> 00:21:40,532
We found water ice,
365
00:21:40,565 --> 00:21:42,200
and that basically blew
our minds.
366
00:21:43,402 --> 00:21:45,237
It showed there is water
down there.
367
00:21:45,270 --> 00:21:47,372
♪
368
00:21:47,406 --> 00:21:49,307
QUINTO:
The discovery of icy clouds
369
00:21:49,341 --> 00:21:52,177
along with the measurements of
the gravitational field
370
00:21:52,210 --> 00:21:53,979
of the giant planet
371
00:21:54,012 --> 00:21:57,783
hint at what may have happened
to the young, rocky ice planet.
372
00:22:00,719 --> 00:22:02,554
Data collected by Cassini
373
00:22:02,587 --> 00:22:05,991
suggests that Saturn no longer
consists of a rocky core
374
00:22:06,024 --> 00:22:08,860
surrounded by
a vast atmosphere,
375
00:22:08,894 --> 00:22:14,099
but rather it is a single object
with no distinct boundaries.
376
00:22:16,168 --> 00:22:19,604
Saturn doesn't really have
a solid surface anywhere.
377
00:22:21,773 --> 00:22:25,143
FLETCHER:
That core that presumably was
there in the first place
378
00:22:25,177 --> 00:22:27,646
would effectively disintegrated
or been mixed in
379
00:22:27,679 --> 00:22:29,748
with all of the other material
that was present.
380
00:22:29,781 --> 00:22:32,884
So it may be today that
the material is still there,
381
00:22:32,918 --> 00:22:35,153
but it's completely distributed
within the envelope
382
00:22:35,187 --> 00:22:36,488
of Saturn itself.
383
00:22:36,521 --> 00:22:38,090
♪
384
00:22:38,123 --> 00:22:41,126
QUINTO:
What began as a rocky, icy world
385
00:22:41,159 --> 00:22:45,297
is now a fully fledged
gas giant.
386
00:22:45,330 --> 00:22:47,599
And within
its gaseous atmosphere,
387
00:22:47,632 --> 00:22:50,535
incredible mechanisms
are at play.
388
00:22:50,569 --> 00:22:53,271
♪
389
00:22:53,305 --> 00:22:54,539
(thunder rumbling)
390
00:22:54,573 --> 00:22:58,844
♪
391
00:22:58,877 --> 00:23:00,712
Saturn's atmosphere is
characterized
392
00:23:00,746 --> 00:23:06,618
by many unusual,
even bizarre features.
393
00:23:06,651 --> 00:23:10,021
Huge weather systems that take
on strange forms,
394
00:23:10,055 --> 00:23:13,358
persisting
for hundreds of years...
395
00:23:15,060 --> 00:23:16,528
perhaps none more striking
396
00:23:16,561 --> 00:23:21,266
than the formation nicknamed
the giant hexagon.
397
00:23:21,299 --> 00:23:26,004
It's over 16,000 miles across,
398
00:23:26,037 --> 00:23:31,276
big enough to swallow almost
four Earth-sized objects.
399
00:23:31,309 --> 00:23:35,046
But what could be driving this
huge planetary weather system?
400
00:23:35,080 --> 00:23:39,050
♪
401
00:23:44,523 --> 00:23:46,992
What powers weather is
very different
402
00:23:47,025 --> 00:23:48,693
depending on where
you find yourself
403
00:23:48,727 --> 00:23:49,728
in the solar system.
404
00:23:49,761 --> 00:23:52,631
♪
405
00:23:52,664 --> 00:23:54,266
BAINES:
The Earth's atmosphere
and the weather on Earth
406
00:23:54,299 --> 00:23:56,001
is, is driven largely
by one thing,
407
00:23:56,034 --> 00:23:57,369
and that's the sun.
408
00:23:57,402 --> 00:23:59,404
And the sun pours
its energy down
409
00:23:59,437 --> 00:24:00,405
through the atmosphere,
410
00:24:00,438 --> 00:24:01,773
and it hits the surface,
411
00:24:01,807 --> 00:24:04,643
and the surface of the Earth
then warms up.
412
00:24:04,676 --> 00:24:08,146
FLETCHER:
With Earth you've got all the
energy coming in from the sun,
413
00:24:08,180 --> 00:24:09,214
heating up the surface,
414
00:24:09,247 --> 00:24:11,516
creating thermals that then,
415
00:24:11,550 --> 00:24:14,753
then drive the atmospheric flows
that we see.
416
00:24:14,786 --> 00:24:18,623
Somewhere like Saturn doesn't
have a surface to be heated up.
417
00:24:18,657 --> 00:24:20,225
So when you compare
the weather systems
418
00:24:20,258 --> 00:24:22,594
on these giant planets
to those that we have on Earth,
419
00:24:22,627 --> 00:24:24,596
you have to sort of tear up
the rulebook a little bit.
420
00:24:26,998 --> 00:24:31,670
QUINTO:
The sun is the great controller
of Earth's atmosphere.
421
00:24:31,703 --> 00:24:33,905
But in the outer reaches
of the solar system,
422
00:24:33,939 --> 00:24:39,711
where Saturn lives,
sunlight is 100 times weaker.
423
00:24:39,744 --> 00:24:41,580
It means some other heat source
424
00:24:41,613 --> 00:24:44,382
must be driving
Saturn's weather,
425
00:24:44,416 --> 00:24:46,051
something deep within--
426
00:24:46,084 --> 00:24:51,690
creating huge, complex forms
that arise in its atmosphere.
427
00:24:51,723 --> 00:24:54,993
♪
428
00:25:00,398 --> 00:25:04,336
As Cassini studies
the cloud tops of Saturn,
429
00:25:04,369 --> 00:25:06,104
it's able to infer a huge amount
430
00:25:06,137 --> 00:25:10,475
about the truly strange world
that must lie beneath
431
00:25:10,508 --> 00:25:14,946
and the energy source
that helps power this planet.
432
00:25:14,980 --> 00:25:18,917
We had a whole variety of
scientific goals at Saturn,
433
00:25:18,950 --> 00:25:20,285
and one of the main ones was
434
00:25:20,318 --> 00:25:23,388
to understand the meteorology
of the Saturn atmosphere
435
00:25:23,421 --> 00:25:26,157
and what energizes the winds
that we see on it,
436
00:25:26,191 --> 00:25:27,926
and so on.
437
00:25:27,959 --> 00:25:30,929
And we have affirmed now
the belief
438
00:25:30,962 --> 00:25:35,000
that atmospheric systems
on Saturn are actually powered
439
00:25:35,033 --> 00:25:36,468
by energy from below;
440
00:25:36,501 --> 00:25:39,070
from an internal heat source
on Saturn.
441
00:25:39,104 --> 00:25:42,774
They're not powered by sunlight,
like we have on the Earth.
442
00:25:42,807 --> 00:25:45,310
♪
443
00:25:45,343 --> 00:25:49,214
(thunder rumbling)
444
00:25:49,247 --> 00:25:52,651
(wind blowing,
lightning crashes)
445
00:25:52,684 --> 00:25:54,386
QUINTO:
Looking deep inside the planet
446
00:25:54,419 --> 00:25:58,657
reveals a heat source shaped
by extreme pressure.
447
00:25:58,690 --> 00:26:01,092
(wind blowing, thunder rumbling)
448
00:26:01,126 --> 00:26:03,094
Within huge clouds of water,
449
00:26:03,128 --> 00:26:08,033
Cassini records lightning
10,000 times more powerful
450
00:26:08,066 --> 00:26:09,167
than any on Earth.
451
00:26:09,200 --> 00:26:13,071
(thunder rumbling,
lightning crackling)
452
00:26:13,104 --> 00:26:16,574
(crackling)
453
00:26:16,608 --> 00:26:21,046
This lightning transforms
methane gas
454
00:26:21,079 --> 00:26:23,982
into enormous clouds of soot.
455
00:26:24,015 --> 00:26:28,820
♪
456
00:26:28,853 --> 00:26:30,989
(crackling)
457
00:26:31,022 --> 00:26:33,124
At 5,000 miles deep,
458
00:26:33,158 --> 00:26:36,261
the pressure of the atmosphere
is 80 times greater
459
00:26:36,294 --> 00:26:40,098
than that at the bottom
of our deepest oceans--
460
00:26:40,131 --> 00:26:43,668
enough to transform
this sooty, graphite rain...
461
00:26:43,702 --> 00:26:46,237
(gems tinkling)
462
00:26:46,271 --> 00:26:47,973
into diamonds.
463
00:26:48,006 --> 00:26:54,312
♪
464
00:26:54,346 --> 00:26:57,315
But even these diamonds are
likely destroyed
465
00:26:57,349 --> 00:27:00,085
by the pressures of Saturn...
466
00:27:01,620 --> 00:27:03,955
eventually dissolving.
467
00:27:03,989 --> 00:27:08,126
♪
468
00:27:17,836 --> 00:27:19,971
18,000 miles down,
469
00:27:20,005 --> 00:27:24,042
Saturn's heat source
is revealed.
470
00:27:24,075 --> 00:27:26,111
Here pressures are so intense
471
00:27:26,144 --> 00:27:29,948
that the atmosphere behaves
like a liquid metal,
472
00:27:29,981 --> 00:27:33,818
able to conduct electricity.
473
00:27:33,852 --> 00:27:39,858
In this state,
molten helium falls like rain.
474
00:27:39,891 --> 00:27:44,396
As this strange rain merges
with the surrounding material,
475
00:27:44,429 --> 00:27:49,200
kinetic energy is released
as incredible amounts of heat.
476
00:27:49,234 --> 00:27:52,303
♪
477
00:27:52,337 --> 00:27:56,174
And it's this extraordinary
heat source
478
00:27:56,207 --> 00:27:59,244
that helps drive
Saturn's weather.
479
00:27:59,277 --> 00:28:04,783
♪
480
00:28:15,593 --> 00:28:19,130
Within just a few hundred
million years of its birth,
481
00:28:19,164 --> 00:28:23,068
Saturn has witnessed
great drama.
482
00:28:23,101 --> 00:28:25,470
Now it will remain
largely unchanged
483
00:28:25,503 --> 00:28:28,473
for billions of years,
484
00:28:28,506 --> 00:28:32,510
vast but still very different
from the planet we know today.
485
00:28:35,980 --> 00:28:38,683
And in time,
its great size will lead
486
00:28:38,716 --> 00:28:42,554
to its ultimate,
iconic transformation.
487
00:28:42,587 --> 00:28:44,122
♪
488
00:28:44,155 --> 00:28:47,926
CUZZI:
The rings have always made
Saturn kind of special.
489
00:28:47,959 --> 00:28:50,929
If you ask a kid to draw
a picture of a planet,
490
00:28:50,962 --> 00:28:53,031
they will draw a picture
of Saturn.
491
00:28:53,064 --> 00:28:55,800
♪
492
00:28:55,834 --> 00:28:58,736
PORCO:
Saturn's rings are what
you would call a debris disc.
493
00:28:58,770 --> 00:29:03,374
It's a collection
of icy particles
494
00:29:03,408 --> 00:29:05,210
ranging in size
495
00:29:05,243 --> 00:29:08,413
from the largest being the size
of small apartment buildings,
496
00:29:08,446 --> 00:29:12,517
all the way down to this... the
tiniest little piece of dust.
497
00:29:12,550 --> 00:29:16,287
QUINTO:
But the sparkling brilliance of
Saturn's rings are a mystery.
498
00:29:16,321 --> 00:29:20,191
CUZZI:
They're so white
and purely ice,
499
00:29:20,225 --> 00:29:24,028
but we know that Saturn's rings
are being bombarded all the time
500
00:29:24,062 --> 00:29:25,997
by meteorites
from the outer solar system,
501
00:29:26,030 --> 00:29:27,398
which are not white,
they're dark,
502
00:29:27,432 --> 00:29:29,067
they're sooty like charcoal.
503
00:29:29,100 --> 00:29:31,436
♪
504
00:29:31,469 --> 00:29:35,140
BROOKS:
We know that the rings are
exposed to in-falling material
505
00:29:35,173 --> 00:29:36,641
and that they appear to be
contaminated
506
00:29:36,674 --> 00:29:38,810
by this material.
507
00:29:38,843 --> 00:29:43,915
I like to give the analogy
of fresh snow in the city.
508
00:29:43,948 --> 00:29:46,284
Eventually over time, the snow
just kind of gets dirty.
509
00:29:46,317 --> 00:29:51,022
♪
510
00:29:51,055 --> 00:29:54,659
So why are the rings so bright?
511
00:29:54,692 --> 00:29:57,829
♪
512
00:29:57,862 --> 00:30:00,465
Thanks to a series of flybys,
513
00:30:00,498 --> 00:30:04,569
Cassini is able to make
a startling discover.
514
00:30:08,173 --> 00:30:10,208
♪
515
00:30:10,241 --> 00:30:11,843
CUZZI:
They cannot stay
516
00:30:11,876 --> 00:30:15,213
as bright and clean
as they are today
517
00:30:15,246 --> 00:30:16,614
if they're much older
518
00:30:16,648 --> 00:30:20,485
than one hundred million years.
519
00:30:20,518 --> 00:30:21,719
At the end of the day,
you have to accept the evidence,
520
00:30:21,753 --> 00:30:23,488
and the evidence says
521
00:30:23,521 --> 00:30:26,391
that the rings are actually
much younger than we thought.
522
00:30:26,424 --> 00:30:28,960
PORCO:
So it means that during
the time of the dinosaurs,
523
00:30:28,993 --> 00:30:30,962
Saturn didn't have rings.
524
00:30:30,995 --> 00:30:34,465
Some velociraptor with
a telescope looking at Saturn
525
00:30:34,499 --> 00:30:35,867
would not have seen rings.
526
00:30:35,900 --> 00:30:40,538
♪
527
00:30:40,572 --> 00:30:45,610
QUINTO:
So if the rings are young,
then where did they come from?
528
00:30:45,643 --> 00:30:47,011
Cassini would give us hints
529
00:30:47,045 --> 00:30:50,315
that the answer lies
not with planet itself,
530
00:30:50,348 --> 00:30:55,153
but with the worlds trapped
in orbit around it:
531
00:30:55,186 --> 00:30:57,055
Saturn's moons.
532
00:30:57,088 --> 00:31:00,792
♪
533
00:31:00,825 --> 00:31:03,494
The surfaces of these moons are
like storybooks,
534
00:31:03,528 --> 00:31:05,964
telling us about the history
535
00:31:05,997 --> 00:31:10,768
of how the Saturn system,
how these moons evolved.
536
00:31:10,802 --> 00:31:16,808
Our job is to unravel the story
that that moon is telling us.
537
00:31:16,841 --> 00:31:18,643
SPILKER:
Saturn has 62 moons.
538
00:31:18,676 --> 00:31:20,545
Some of them look
like flying saucers
539
00:31:20,578 --> 00:31:23,581
or, or pancakes or potatoes,
540
00:31:23,615 --> 00:31:24,816
very irregularly shaped.
541
00:31:24,849 --> 00:31:26,117
Once a moon gets bigger,
542
00:31:26,150 --> 00:31:28,419
its gravity tends
to round it out,
543
00:31:28,453 --> 00:31:32,423
and you get more of
a rounded, nicely shaped moon.
544
00:31:32,457 --> 00:31:34,525
♪
545
00:31:35,727 --> 00:31:38,896
LUNINE:
The moons are
the archaeological debris
546
00:31:38,930 --> 00:31:43,067
from planet formation,
547
00:31:43,101 --> 00:31:46,070
and the, their size,
their orbits, uh,
548
00:31:46,104 --> 00:31:47,905
even their composition,
549
00:31:47,939 --> 00:31:52,110
tell us about the details
of the environment
550
00:31:52,143 --> 00:31:53,244
within which they form.
551
00:31:53,278 --> 00:31:57,048
So it's possible
in the case of Saturn
552
00:31:57,081 --> 00:31:59,984
that we can use
the different moons
553
00:32:00,018 --> 00:32:03,354
to understand different eras,
different epochs
554
00:32:03,388 --> 00:32:05,523
of the evolution of Saturn.
555
00:32:05,556 --> 00:32:07,959
♪
556
00:32:07,992 --> 00:32:09,928
QUINTO:
As Cassini continues
its journey,
557
00:32:09,961 --> 00:32:14,465
it reveals many moons
made almost entirely of ice.
558
00:32:14,499 --> 00:32:16,968
♪
559
00:32:17,001 --> 00:32:20,838
And some of them take on
extraordinary forms
560
00:32:20,872 --> 00:32:22,907
in and around the rings.
561
00:32:22,940 --> 00:32:25,009
♪
562
00:32:39,557 --> 00:32:43,995
Cassini analyzes the ice moons
in ever-greater detail,
563
00:32:44,028 --> 00:32:48,099
and it becomes apparent
many of them are made
564
00:32:48,132 --> 00:32:53,004
of the same icy material
as the rings themselves,
565
00:32:53,037 --> 00:32:55,973
which suggests
that Saturn's rings
566
00:32:56,007 --> 00:32:59,243
may once have been a moon.
567
00:32:59,277 --> 00:33:02,280
PORCO:
The satellite system that
we're seeing around Saturn now
568
00:33:02,313 --> 00:33:05,650
is probably not the original
satellite system that it had,
569
00:33:05,683 --> 00:33:07,218
because if the rings
were created
570
00:33:07,251 --> 00:33:10,621
by the destruction of
one or two preexisting moons,
571
00:33:10,655 --> 00:33:13,124
it means that
there were moons before
572
00:33:13,157 --> 00:33:16,794
that don't exist any longer.
573
00:33:20,298 --> 00:33:23,501
♪
574
00:33:33,144 --> 00:33:35,446
QUINTO:
Millions of years ago,
575
00:33:35,480 --> 00:33:38,383
Saturn has an extra moon...
576
00:33:38,416 --> 00:33:43,921
♪
577
00:33:43,955 --> 00:33:47,125
perhaps 250 miles across
578
00:33:47,158 --> 00:33:50,361
and formed almost entirely
of ice.
579
00:33:50,395 --> 00:33:53,965
♪
580
00:33:53,998 --> 00:33:58,202
But this moon is doomed.
581
00:33:58,236 --> 00:33:59,971
It's orbiting just too close
582
00:34:00,004 --> 00:34:03,241
to resist the immense forces
of Saturn's gravity.
583
00:34:03,274 --> 00:34:07,412
♪
584
00:34:07,445 --> 00:34:08,813
SPILKER:
The rings probably formed
585
00:34:08,846 --> 00:34:12,350
from an object
that got too close to Saturn.
586
00:34:12,383 --> 00:34:14,619
There's this invisible boundary
around Saturn
587
00:34:14,652 --> 00:34:16,087
called the Roche limit,
588
00:34:16,120 --> 00:34:18,756
and that's the limit, depending
on what you're made of,
589
00:34:18,790 --> 00:34:20,725
where Saturn's gravity is
strong enough
590
00:34:20,758 --> 00:34:22,226
it will actually pull you apart.
591
00:34:22,260 --> 00:34:24,262
That the gravity
on the side closer to Saturn
592
00:34:24,295 --> 00:34:25,596
is strong enough that
593
00:34:25,630 --> 00:34:26,931
compared to the gravity
on the other side,
594
00:34:26,964 --> 00:34:28,366
it will literally rip you apart.
595
00:34:28,399 --> 00:34:30,701
You don't have enough gravity
of your own
596
00:34:30,735 --> 00:34:31,803
to stay together.
597
00:34:31,836 --> 00:34:35,406
♪
598
00:34:44,449 --> 00:34:49,720
QUINTO:
A leading theory suggests that
just beyond Saturn's atmosphere,
599
00:34:49,754 --> 00:34:51,856
an ice moon approaches close to
600
00:34:51,889 --> 00:34:54,959
or even just inside
its Roche limit.
601
00:34:54,992 --> 00:34:57,495
♪
602
00:34:57,528 --> 00:34:59,730
(rumbling)
603
00:34:59,764 --> 00:35:02,300
As Saturn's immense
gravitational force
604
00:35:02,333 --> 00:35:03,768
pulls it apart,
605
00:35:03,801 --> 00:35:07,972
the moon begins to rupture
catastrophically...
606
00:35:08,005 --> 00:35:11,709
♪
607
00:35:11,742 --> 00:35:13,678
(rumbling)
608
00:35:13,711 --> 00:35:17,515
a world ripped apart
by its proximity to a giant.
609
00:35:17,548 --> 00:35:22,687
♪
610
00:35:31,229 --> 00:35:34,599
(rumbling continues)
611
00:35:45,510 --> 00:35:49,313
♪
612
00:35:49,347 --> 00:35:54,485
(distant rumbling)
613
00:36:06,898 --> 00:36:10,134
Up to 17,000 trillion tons
of ice...
614
00:36:10,167 --> 00:36:12,737
(rumbling)
615
00:36:12,770 --> 00:36:15,773
breaks apart
in orbit around Saturn.
616
00:36:19,443 --> 00:36:21,913
♪
617
00:36:21,946 --> 00:36:25,516
And thanks to the speeds
this material is travelling,
618
00:36:25,550 --> 00:36:28,686
it's likely that
in just a few days,
619
00:36:28,719 --> 00:36:31,556
it spreads out to encircle
the great giant.
620
00:36:31,589 --> 00:36:34,759
♪
621
00:36:38,596 --> 00:36:43,267
Saturn's iconic ring is now
in place.
622
00:36:43,301 --> 00:36:49,040
♪
623
00:36:49,073 --> 00:36:52,543
But as Cassini turns
its instruments towards it,
624
00:36:52,577 --> 00:36:57,048
it sees a single ring
transformed.
625
00:36:57,081 --> 00:37:00,785
♪
626
00:37:04,055 --> 00:37:08,059
PORCO:
The images we returned,
they were phenomenal.
627
00:37:08,092 --> 00:37:13,197
They were resolution factor
of maybe 20 times better
628
00:37:13,231 --> 00:37:15,032
than anything we had had before.
629
00:37:15,066 --> 00:37:19,203
♪
630
00:37:23,107 --> 00:37:24,909
QUINTO:
Today Cassini reveals
631
00:37:24,942 --> 00:37:30,147
how Saturn's giant rings have
evolved.
632
00:37:30,181 --> 00:37:34,218
This debris now forms a disc
wider than Jupiter...
633
00:37:34,252 --> 00:37:36,120
♪
634
00:37:36,153 --> 00:37:39,824
yet on average
just 30 feet thick.
635
00:37:40,992 --> 00:37:44,929
Within, moon-sized chunks of ice
orbit the structure,
636
00:37:44,962 --> 00:37:46,864
clearing great voids...
637
00:37:46,897 --> 00:37:48,933
♪
638
00:37:48,966 --> 00:37:53,270
turning one ring into many.
639
00:37:53,304 --> 00:37:55,873
♪
640
00:37:55,906 --> 00:37:58,109
But it's as Cassini captures
images
641
00:37:58,142 --> 00:38:01,245
with the sun directly
above the equator
642
00:38:01,278 --> 00:38:05,916
that the most surprising feature
of the rings emerges.
643
00:38:05,950 --> 00:38:09,287
PORCO:
We knew this was going to be
a time
644
00:38:09,320 --> 00:38:11,922
for us to investigate
the third dimension,
645
00:38:11,956 --> 00:38:13,758
something that
you don't get to see
646
00:38:13,791 --> 00:38:16,627
when you just look
at a picture of Saturn's rings.
647
00:38:16,661 --> 00:38:19,964
And what we found was
staggering.
648
00:38:19,997 --> 00:38:23,734
♪
649
00:38:29,440 --> 00:38:33,411
Just right out of the gate,
we saw vertical structures.
650
00:38:33,444 --> 00:38:36,714
I just can't tell you how
surprised we were to see this.
651
00:38:36,747 --> 00:38:42,720
It's just... the spectacle of it
was just unanticipated.
652
00:38:42,753 --> 00:38:47,692
I have just imagined
flying along in a shuttle-craft
653
00:38:47,725 --> 00:38:50,394
across the ring, right,
654
00:38:50,428 --> 00:38:53,597
close to the ring,
so to my perspective
655
00:38:53,631 --> 00:38:57,301
it would be almost like
it was an infinite sheet
656
00:38:57,334 --> 00:39:00,037
of gleaming debris,
657
00:39:00,071 --> 00:39:02,606
and I'm flying along and
flying along and flying along,
658
00:39:02,640 --> 00:39:04,675
and suddenly I come upon a wall
of rubble
659
00:39:04,709 --> 00:39:06,143
that's two miles high.
660
00:39:06,177 --> 00:39:08,646
♪
661
00:39:11,649 --> 00:39:16,053
I mean, is that cool or what?
(chuckles)
662
00:39:16,087 --> 00:39:17,922
Really I've, I've said over
and over again,
663
00:39:17,955 --> 00:39:19,323
they should put that in a movie.
664
00:39:19,356 --> 00:39:21,692
♪
665
00:39:21,726 --> 00:39:24,428
QUINTO:
This once-tiny world
of rock and ice
666
00:39:24,462 --> 00:39:29,533
that has seen the
most dramatic transformations
667
00:39:29,567 --> 00:39:34,739
is today the solar system's
greatest jewel.
668
00:39:34,772 --> 00:39:37,908
♪
669
00:39:42,913 --> 00:39:45,683
After more than decade in orbit,
670
00:39:45,716 --> 00:39:49,887
Cassini has forever deepened
our understanding of Saturn.
671
00:39:49,920 --> 00:39:55,659
But its mission is far
from over.
672
00:39:55,693 --> 00:40:00,030
Because just beyond the rings
lies another treasure:
673
00:40:00,064 --> 00:40:03,667
a tiny world
that may hold answers
674
00:40:03,701 --> 00:40:05,169
to some of our deepest questions
675
00:40:05,202 --> 00:40:09,340
about the possibility of life
in the solar system...
676
00:40:09,373 --> 00:40:11,542
♪
677
00:40:11,575 --> 00:40:14,945
the ice moon Enceladus.
678
00:40:18,616 --> 00:40:21,585
Enceladus is one the moons in
a regular orbit around Saturn.
679
00:40:21,619 --> 00:40:25,055
It's quite small,
its diameter is 500 kilometers.
680
00:40:29,493 --> 00:40:33,998
PAPPALARDO:
From far away it looks smooth.
681
00:40:34,031 --> 00:40:35,599
When we look at it close up,
682
00:40:35,633 --> 00:40:38,803
we see that those smooth areas
are really places
683
00:40:38,836 --> 00:40:40,704
where there's been fracture
upon fracture,
684
00:40:40,738 --> 00:40:42,506
fault upon fault,
685
00:40:42,540 --> 00:40:45,843
destroying, disrupting
the surface.
686
00:40:45,876 --> 00:40:47,578
(crackling sound)
687
00:40:47,611 --> 00:40:51,081
♪
688
00:40:51,115 --> 00:40:54,618
PORCO:
We got to see these
five prominent fractures,
689
00:40:54,652 --> 00:40:57,988
deep, long fractures crossing
this region.
690
00:40:58,022 --> 00:41:02,459
And eventually, over time,
we were able to find
691
00:41:02,493 --> 00:41:07,565
that there were geysers coming
from those fractures.
692
00:41:07,598 --> 00:41:12,069
♪
693
00:41:12,102 --> 00:41:18,409
QUINTO:
Cassini discovers this tiny moon
is alive with activity.
694
00:41:18,442 --> 00:41:24,081
Its giant plumes eject over 500
pounds of ice and water vapor
695
00:41:24,114 --> 00:41:27,751
into space every second.
696
00:41:27,785 --> 00:41:30,855
DOUGHERTY:
I think for me and for
a lot of scientists on Cassini,
697
00:41:30,888 --> 00:41:34,291
the biggest surprise was
that Enceladus was active.
698
00:41:34,325 --> 00:41:35,726
There's this little moon
out there
699
00:41:35,759 --> 00:41:37,428
which is supposed to be dead,
700
00:41:37,461 --> 00:41:40,464
and it's spewing out this vast
amount of water vapor.
701
00:41:42,199 --> 00:41:43,968
♪
702
00:41:44,001 --> 00:41:48,572
PORCO:
It became clear
once we had found the plume
703
00:41:48,606 --> 00:41:51,675
that we needed to get
as deep into it as possible.
704
00:41:55,279 --> 00:41:58,816
Cassini, over 13 years,
did 23 flybys.
705
00:41:58,849 --> 00:42:01,819
(Cassini whooshing by)
706
00:42:01,852 --> 00:42:06,023
We flew through the plume
in about a dozen of those.
707
00:42:06,056 --> 00:42:09,260
♪
708
00:42:14,431 --> 00:42:17,835
QUINTO:
Piloted from
nearly a billion miles away...
709
00:42:17,868 --> 00:42:20,471
♪
710
00:42:20,504 --> 00:42:23,207
Cassini, on its closest flyby,
711
00:42:23,240 --> 00:42:29,613
passes within just 30 miles
of the surface of Enceladus.
712
00:42:29,647 --> 00:42:33,817
And what its instruments detect
is breathtaking.
713
00:42:36,787 --> 00:42:38,956
SPILKER:
We were able to sample directly
714
00:42:38,989 --> 00:42:42,993
material coming out
of Enceladus's plume.
715
00:42:43,027 --> 00:42:45,129
And what a wonderland we found.
716
00:42:45,162 --> 00:42:51,201
LUNINE:
We are sampling a subterranean
or subsurface ocean.
717
00:42:51,235 --> 00:42:54,772
And indeed Cassini,
as it flew through the plume,
718
00:42:54,805 --> 00:42:58,542
found, uh, not only water vapor
and water ice,
719
00:42:58,575 --> 00:43:03,314
but salts.
720
00:43:03,347 --> 00:43:04,882
PAPPALARDO:
Some of these particles,
721
00:43:04,915 --> 00:43:07,084
the fact that they're salty,
722
00:43:07,117 --> 00:43:09,119
tells us almost certainly
723
00:43:09,153 --> 00:43:13,157
that they came
from an underground ocean.
724
00:43:13,190 --> 00:43:16,026
Under that ice
there is an ocean,
725
00:43:16,060 --> 00:43:18,929
and then beneath that ocean
is rock.
726
00:43:20,264 --> 00:43:24,602
QUINTO:
And it is there
because of Saturn.
727
00:43:24,635 --> 00:43:27,304
As Enceladus moves
around the planet,
728
00:43:27,338 --> 00:43:30,474
its vast gravitational force
pulls at the moon,
729
00:43:30,507 --> 00:43:31,742
holding it in orbit.
730
00:43:31,775 --> 00:43:34,311
♪
731
00:43:34,345 --> 00:43:35,613
But every couple of orbits,
732
00:43:35,646 --> 00:43:41,685
another larger moon called Dione
draws Enceladus back.
733
00:43:41,719 --> 00:43:46,924
This process repeatedly
stretches and squeezes its core,
734
00:43:46,957 --> 00:43:52,429
warming and melting
the icy interior.
735
00:43:52,463 --> 00:43:55,833
♪
736
00:43:55,866 --> 00:44:00,204
But it's what Cassini finds next
that changes everything.
737
00:44:00,237 --> 00:44:05,542
♪
738
00:44:05,576 --> 00:44:10,781
As the plumes are analyzed
in ever greater detail,
739
00:44:10,814 --> 00:44:14,284
scientists discover
complex organic compounds.
740
00:44:14,318 --> 00:44:16,954
♪
741
00:44:16,987 --> 00:44:19,256
DOUGHERTY:
Once we got over our shock,
we then started focusing
742
00:44:19,289 --> 00:44:22,559
on the fact that there was
organic material leaking out
743
00:44:22,593 --> 00:44:23,861
from this little moon as well,
744
00:44:23,894 --> 00:44:25,396
and then everyone got excited.
745
00:44:25,429 --> 00:44:28,832
♪
746
00:44:31,869 --> 00:44:33,604
CUZZI:
So here you have a hot,
747
00:44:33,637 --> 00:44:40,511
liquid, salty, organic-rich,
subsurface ocean,
748
00:44:40,544 --> 00:44:44,982
and a lot of people feel that
this is one of the better places
749
00:44:45,015 --> 00:44:47,818
where life may even exist today
in the solar system.
750
00:44:47,851 --> 00:44:50,454
PORCO:
I don't know what to think.
751
00:44:50,487 --> 00:44:52,089
I just know that, you know,
752
00:44:52,122 --> 00:44:56,360
Enceladus is a place
that we know more about.
753
00:44:56,393 --> 00:44:59,396
It's a,
it's an alien environment
754
00:44:59,430 --> 00:45:03,033
that meets
all our formal requirements
755
00:45:03,067 --> 00:45:06,837
for a place
that could support life.
756
00:45:06,870 --> 00:45:12,209
♪
757
00:45:17,081 --> 00:45:19,516
QUINTO:
Deep beneath
Enceladus's icy shell,
758
00:45:19,550 --> 00:45:22,953
hot rock is in contact
with water...
759
00:45:22,986 --> 00:45:25,155
♪
760
00:45:25,189 --> 00:45:29,727
almost certainly creating
hydrothermal vents.
761
00:45:29,760 --> 00:45:31,462
♪
762
00:45:31,495 --> 00:45:37,734
On Earth, these types of vents
support a multitude of life,
763
00:45:37,768 --> 00:45:39,036
and leading theories suggest
764
00:45:39,069 --> 00:45:41,605
that these might have been
the setting
765
00:45:41,638 --> 00:45:46,376
for the emergence
of life on Earth.
766
00:45:47,911 --> 00:45:49,947
Which makes some wonder
767
00:45:49,980 --> 00:45:54,585
if the same thing is happening
on Enceladus.
768
00:45:54,618 --> 00:45:58,055
LUNINE:
I think that Enceladus
may be the first place
769
00:45:58,088 --> 00:46:00,958
where we will discover
a form of life
770
00:46:00,991 --> 00:46:03,961
that's independent
from life on the Earth,
771
00:46:03,994 --> 00:46:07,765
which would be one of
the most spectacular discoveries
772
00:46:07,798 --> 00:46:09,333
that science has ever made.
773
00:46:09,366 --> 00:46:10,501
If it doesn't have life,
774
00:46:10,534 --> 00:46:12,202
that would be equally amazing
too,
775
00:46:12,236 --> 00:46:15,572
because here you have
the conditions right for life,
776
00:46:15,606 --> 00:46:17,274
and yet it didn't form.
777
00:46:17,307 --> 00:46:21,345
So maybe you need something else
to get life started.
778
00:46:21,378 --> 00:46:25,983
♪
779
00:46:26,016 --> 00:46:28,652
QUINTO:
But for Cassini's scientists,
780
00:46:28,685 --> 00:46:32,122
the exotic world
under the ice of Enceladus
781
00:46:32,156 --> 00:46:34,658
is a bittersweet discovery.
782
00:46:34,691 --> 00:46:37,728
♪
783
00:46:49,006 --> 00:46:51,475
DOUGHERTY:
As we were approaching
the end-of-mission phase,
784
00:46:51,508 --> 00:46:53,644
we were essentially running out
of fuel,
785
00:46:53,677 --> 00:46:56,313
we knew we had to end
the mission somehow.
786
00:46:56,346 --> 00:46:59,483
And to protect,
in particular protect Enceladus,
787
00:46:59,516 --> 00:47:01,818
because it would be pretty bad
to go back to Enceladus
788
00:47:01,852 --> 00:47:03,320
and discover life,
789
00:47:03,353 --> 00:47:06,857
and it turned out to be Earth
microbes on Enceladus, so...
790
00:47:06,890 --> 00:47:08,158
We didn't sterilize Cassini.
791
00:47:08,192 --> 00:47:09,426
We didn't know we had to.
792
00:47:09,459 --> 00:47:13,630
You don't want to go
to a place like Enceladus
793
00:47:13,664 --> 00:47:15,199
and find something
794
00:47:15,232 --> 00:47:17,201
that the previous spacecraft
delivered there.
795
00:47:17,234 --> 00:47:23,040
MAN (on radio):
This is ACS One, we just had
transition to high rate mode.
796
00:47:23,073 --> 00:47:27,811
QUINTO:
Cassini ends its mission
in spectacular fashion,
797
00:47:27,845 --> 00:47:30,080
making a series
of ever-closer orbits
798
00:47:30,113 --> 00:47:32,916
to study the planet's rings
799
00:47:32,950 --> 00:47:37,221
before a final dive
into Saturn's atmosphere,
800
00:47:37,254 --> 00:47:41,725
a journey from which
it will never return.
801
00:47:41,758 --> 00:47:43,460
DOUGHERTY:
Some of us were concerned
802
00:47:43,493 --> 00:47:45,529
the spacecraft wouldn't even
survive the first orbit,
803
00:47:45,562 --> 00:47:47,497
because we were going
through the gap
804
00:47:47,531 --> 00:47:50,067
between the rings
and the atmosphere of Saturn.
805
00:47:50,100 --> 00:47:51,401
We didn't know what was there.
806
00:47:51,435 --> 00:47:53,971
We thought it was empty,
but we weren't sure.
807
00:47:54,004 --> 00:47:56,707
(Cassini whooshing)
808
00:47:56,740 --> 00:48:00,877
QUINTO:
Cassini survives its approach
to Saturn intact
809
00:48:00,911 --> 00:48:04,214
and continues on
towards its demise.
810
00:48:04,248 --> 00:48:05,816
♪
811
00:48:05,849 --> 00:48:07,050
DOUGHERTY:
We're out at JPL
812
00:48:07,084 --> 00:48:08,518
watching the signal coming
from the spacecraft,
813
00:48:08,552 --> 00:48:09,620
and there was a spike.
814
00:48:09,653 --> 00:48:10,621
And it went away,
815
00:48:10,654 --> 00:48:12,189
but it seemed to come back.
816
00:48:12,222 --> 00:48:15,525
Because the spacecraft hadn't
been told its life was ending,
817
00:48:15,559 --> 00:48:18,428
and so it had been programmed
to keep in touch with the Earth.
818
00:48:18,462 --> 00:48:21,598
So it moved itself.
819
00:48:21,632 --> 00:48:23,400
MAN (on radio):
Okay, we call loss of signal
820
00:48:23,433 --> 00:48:25,669
in one-one-five-five-four-six.
821
00:48:25,702 --> 00:48:26,970
FLETCHER:
The last command
822
00:48:27,004 --> 00:48:29,973
that my colleagues uploaded
to the spacecraft
823
00:48:30,007 --> 00:48:33,777
was a list of the 200 or some
scientists and engineers
824
00:48:33,810 --> 00:48:35,646
that had been involved
in the development
825
00:48:35,679 --> 00:48:37,014
of one of the instruments,
826
00:48:37,047 --> 00:48:40,183
which means that as Cassini was
literally disintegrating,
827
00:48:40,217 --> 00:48:43,720
in its computer memory was
a final thought of home.
828
00:48:43,754 --> 00:48:46,623
And I think that's just
a tremendous, tremendous thing.
829
00:48:46,657 --> 00:48:47,991
(wind blowing)
830
00:48:48,025 --> 00:48:49,426
MAN:
We have just heard
831
00:48:49,459 --> 00:48:51,595
the signal from the spacecraft
is gone,
832
00:48:51,628 --> 00:48:55,198
and within the next 45 seconds,
so will be the spacecraft.
833
00:48:55,232 --> 00:48:56,767
(hissing, rumbling)
834
00:48:56,800 --> 00:48:59,469
DOUGHERTY:
And then it lost control,
it began to tumble.
835
00:48:59,503 --> 00:49:00,871
(whooshing)
836
00:49:00,904 --> 00:49:02,806
QUINTO:
The world that had borne witness
837
00:49:02,839 --> 00:49:07,577
to some of the greatest dramas
in the solar system's history
838
00:49:07,611 --> 00:49:12,950
consumes the craft that has
given us its remarkable story.
839
00:49:12,983 --> 00:49:16,153
♪
840
00:49:26,296 --> 00:49:29,366
♪
841
00:49:36,173 --> 00:49:37,541
Congratulations to you all.
842
00:49:37,574 --> 00:49:40,711
(applause)
843
00:49:40,744 --> 00:49:42,979
WEBSTER:
I was supposed to call
end of mission.
844
00:49:43,013 --> 00:49:46,817
"Thanks and Godspeed Cassini."
845
00:49:46,850 --> 00:49:48,151
I couldn't get the words out.
846
00:49:48,185 --> 00:49:51,388
And there was some applause
but mostly people just...
847
00:49:55,492 --> 00:49:57,394
People were just looking
at each other.
848
00:49:57,427 --> 00:49:59,496
It was, it was, it was so sad.
849
00:49:59,529 --> 00:50:01,031
Really, really sad.
850
00:50:02,699 --> 00:50:04,735
It's still hard.
851
00:50:13,176 --> 00:50:17,314
♪
852
00:50:20,083 --> 00:50:21,518
QUINTO:
We journeyed out to Saturn
853
00:50:21,551 --> 00:50:26,890
to see this great beauty
up close,
854
00:50:26,923 --> 00:50:30,026
to understand its deep history,
855
00:50:30,060 --> 00:50:32,262
and explore its rings.
856
00:50:35,165 --> 00:50:37,834
But in the end we were rewarded
857
00:50:37,868 --> 00:50:41,505
with something
far more profound:
858
00:50:41,538 --> 00:50:45,742
early hints
of a second home for life.
859
00:50:45,776 --> 00:50:48,678
♪
860
00:50:48,712 --> 00:50:52,416
CUZZI:
It's sad that Cassini is no
longer up there doing its thing,
861
00:50:52,449 --> 00:50:56,286
but it has left us
a tremendous legacy of data
862
00:50:56,319 --> 00:50:59,723
that is going
to keep us all busy for decades.
863
00:50:59,756 --> 00:51:00,857
It's revealed so much,
864
00:51:00,891 --> 00:51:03,193
and there's still secrets in
that data
865
00:51:03,226 --> 00:51:04,528
that are going to become
unlocked.
866
00:51:04,561 --> 00:51:06,997
I'm convinced graduate students
20 years from now
867
00:51:07,030 --> 00:51:08,965
will be finding new things
in that data
868
00:51:08,999 --> 00:51:10,500
that we didn't, didn't know were
there.
869
00:51:10,534 --> 00:51:16,306
♪
870
00:51:16,339 --> 00:51:19,309
SPILKER:
Now when I go out in the
night sky and look at Saturn,
871
00:51:19,342 --> 00:51:21,778
I know Cassini is there,
872
00:51:21,812 --> 00:51:26,483
that the bits of Cassini will
always be part of Saturn.
873
00:51:26,516 --> 00:51:29,419
Saturn will never be quite
the same.
874
00:51:29,453 --> 00:51:31,855
We landed a device
of our own making
875
00:51:31,888 --> 00:51:38,595
on a world in...
in the outer solar system.
876
00:51:38,628 --> 00:51:42,666
We spent 13 years, you know,
in the...
877
00:51:45,268 --> 00:51:48,472
just methodically, quietly...
878
00:51:52,509 --> 00:51:54,377
just monitoring, observing.
879
00:51:54,411 --> 00:51:58,281
And... it's...
880
00:51:58,315 --> 00:51:59,783
it, to me, it represents
881
00:51:59,816 --> 00:52:03,920
the best that humanity has
to give.
882
00:52:03,954 --> 00:52:06,389
It's really...
it's us at our finest.
883
00:52:06,423 --> 00:52:09,459
♪
884
00:52:13,864 --> 00:52:16,199
Major funding for "NOVA"
is provided by the following:
885
00:52:48,598 --> 00:52:51,568
To order this program
on DVD or Blu-ray,
886
00:52:51,601 --> 00:52:56,106
visit ShopPBS
or call 1-800-PLAY-PBS.
887
00:52:56,139 --> 00:52:59,809
This program is also available
on Amazon Prime Video.
888
00:52:59,843 --> 00:53:01,778
♪
61854
Can't find what you're looking for?
Get subtitles in any language from opensubtitles.com, and translate them here.