1
00:00:00,007 --> 00:00:03,090
(dramatic music)
2
00:00:03,090 --> 00:00:07,173
Earth is born out of chaos and catastrophe.
3
00:00:08,340 --> 00:00:11,010
Despite such hostile conditions,
4
00:00:11,010 --> 00:00:13,563
life emerges on our planet,
5
00:00:15,390 --> 00:00:18,360
but it must withstand deadly disasters,
6
00:00:18,360 --> 00:00:19,863
again and again.
7
00:00:22,080 --> 00:00:25,380
Planet Earth is a wild world.
8
00:00:25,380 --> 00:00:28,053
Shaken by unimaginable impacts,
9
00:00:30,330 --> 00:00:33,333
volcanic eruptions that flood the landscape,
10
00:00:34,620 --> 00:00:38,520
and drastic climate changes that lead to ice ages
11
00:00:38,520 --> 00:00:41,763
that freeze the world from pole to pole.
12
00:00:43,260 --> 00:00:47,223
Yet each assault creates a path for something new.
13
00:00:48,270 --> 00:00:51,240
Life always finds a way,
14
00:00:51,240 --> 00:00:54,583
despite being constantly put to the test.
15
00:00:54,583 --> 00:00:56,010
(dramatic music continues)
16
00:00:56,010 --> 00:00:58,020
Without these catastrophes,
17
00:00:58,020 --> 00:01:03,020
life as we know it would not exist on our fateful planet.
18
00:01:12,510 --> 00:01:13,800
Chile.
19
00:01:13,800 --> 00:01:15,960
In the heart of the Atacama Desert,
20
00:01:15,960 --> 00:01:20,010
scientists are trying to understand how our home,
21
00:01:20,010 --> 00:01:22,143
Planet Earth, came into being.
22
00:01:25,530 --> 00:01:27,780
Astronomers are like archeologists,
23
00:01:27,780 --> 00:01:30,693
so we have somehow to reconstruct the past.
24
00:01:32,340 --> 00:01:34,110
Professor Thomas Henning is one
25
00:01:34,110 --> 00:01:37,890
of the world's leading experts on planet formation.
26
00:01:37,890 --> 00:01:39,960
We live in a period of discoveries
27
00:01:39,960 --> 00:01:44,280
and it's really absolutely exciting to be part of this
28
00:01:44,280 --> 00:01:47,820
and to be part of this great adventure
29
00:01:47,820 --> 00:01:50,673
to unravel the mysteries of the universe.
30
00:01:52,560 --> 00:01:55,890
As the end of the last century came to a close,
31
00:01:55,890 --> 00:01:58,710
a staggering discovery was made.
32
00:01:58,710 --> 00:02:01,770
Scientists had measured the slightly shifting light
33
00:02:01,770 --> 00:02:02,673
of a star.
34
00:02:03,750 --> 00:02:06,990
From the data, they could tell that a giant object had
35
00:02:06,990 --> 00:02:09,573
to be pulling on it: a planet.
36
00:02:10,470 --> 00:02:14,370
This was the first planet outside our own solar system
37
00:02:14,370 --> 00:02:15,780
to be discovered.
38
00:02:15,780 --> 00:02:17,883
A so-called exoplanet.
39
00:02:19,470 --> 00:02:21,120
It was an absolute game changer,
40
00:02:21,120 --> 00:02:24,360
I think was one of the most fundamental discoveries.
41
00:02:24,360 --> 00:02:28,473
And in that time, we can put our solar system context.
42
00:02:30,300 --> 00:02:34,110
This newly-found planet is far from unique.
43
00:02:34,110 --> 00:02:37,440
Scientists believe that in just our galaxy alone,
44
00:02:37,440 --> 00:02:40,233
there are around 100 billion planets.
45
00:02:41,580 --> 00:02:44,070
Many could even foster life.
46
00:02:44,070 --> 00:02:46,410
By researching these distant planets,
47
00:02:46,410 --> 00:02:49,200
scientists hope that they can shed more light
48
00:02:49,200 --> 00:02:52,470
on our own planet and its formation,
49
00:02:52,470 --> 00:02:55,173
but detecting them remains a challenge.
50
00:02:59,550 --> 00:03:02,700
One of the technique is actually using a dip
51
00:03:02,700 --> 00:03:04,020
in the light intensity.
52
00:03:04,020 --> 00:03:07,140
So let's imagine that the lamp would be the star
53
00:03:07,140 --> 00:03:08,850
and this would be the planet.
54
00:03:08,850 --> 00:03:12,930
Then we would see a slight dip in the light intensity,
55
00:03:12,930 --> 00:03:14,400
and we could conclude
56
00:03:14,400 --> 00:03:16,953
that a planet crossed the stellar surface.
57
00:03:18,120 --> 00:03:19,890
These the so-called transits
58
00:03:19,890 --> 00:03:21,600
can help determine a variety
59
00:03:21,600 --> 00:03:25,020
of different exoplanet characteristics,
60
00:03:25,020 --> 00:03:27,570
from the size of the exoplanet's orbit
61
00:03:27,570 --> 00:03:30,780
to the radius of the planet itself,
62
00:03:30,780 --> 00:03:32,940
even its atmosphere.
63
00:03:32,940 --> 00:03:36,330
But there is one thing this method does not provide.
64
00:03:36,330 --> 00:03:39,450
Our ultimate goal is to image planets,
65
00:03:39,450 --> 00:03:42,780
and that is actually really, really difficult.
66
00:03:42,780 --> 00:03:44,253
And the reason for that is
67
00:03:44,253 --> 00:03:48,693
that the central stellar object is over shining the planet.
68
00:03:50,523 --> 00:03:52,620
To image distant exoplanets,
69
00:03:52,620 --> 00:03:56,310
Professor Henning works at a high-tech facility,
70
00:03:56,310 --> 00:03:59,523
the European Southern Observatory at Mount Parana.
71
00:04:00,420 --> 00:04:03,870
Located in the Atacama Desert in Northern Chile,
72
00:04:03,870 --> 00:04:08,103
the astronomical observatory towers above the desert.
73
00:04:09,480 --> 00:04:12,870
By analyzing exoplanets and their systems,
74
00:04:12,870 --> 00:04:16,020
scientists can find out how our solar system
75
00:04:16,020 --> 00:04:18,840
and Planet Earth have formed,
76
00:04:18,840 --> 00:04:21,420
and they also try to discover
77
00:04:21,420 --> 00:04:24,112
if there is life in outer space.
78
00:04:24,112 --> 00:04:26,044
(awe-inspiring music)
79
00:04:26,044 --> 00:04:27,360
This is a magic place.
80
00:04:27,360 --> 00:04:30,300
The landscape is just breathtaking.
81
00:04:30,300 --> 00:04:33,360
It's one of the greatest places for astronomy.
82
00:04:33,360 --> 00:04:35,520
We have many clear nights
83
00:04:35,520 --> 00:04:37,710
and we have very little water in the atmosphere.
84
00:04:37,710 --> 00:04:39,870
It's very dry, and that's great
85
00:04:39,870 --> 00:04:42,153
for observing stars and planets.
86
00:04:43,890 --> 00:04:46,020
For this reason, a special array
87
00:04:46,020 --> 00:04:48,510
of telescopes is utilized here
88
00:04:48,510 --> 00:04:52,083
to help scientists understand the birth of our own planet.
89
00:04:53,160 --> 00:04:57,393
It is called the VLT or very large telescope.
90
00:05:00,360 --> 00:05:04,470
Each of the four 27-feet telescopes can take pictures
91
00:05:04,470 --> 00:05:08,970
of tiny celestial objects over 4 billion times fainter
92
00:05:08,970 --> 00:05:12,120
than what can be seen with the naked eye.
93
00:05:12,120 --> 00:05:14,610
But even this is not enough.
94
00:05:14,610 --> 00:05:16,110
Beneath the telescopes,
95
00:05:16,110 --> 00:05:20,190
a collection of high-tech systems enables the scientists
96
00:05:20,190 --> 00:05:23,850
to create a virtual mega telescope.
97
00:05:23,850 --> 00:05:25,860
We are not only using a single telescope
98
00:05:25,860 --> 00:05:30,570
but we are combining four of the big telescopes
99
00:05:30,570 --> 00:05:33,960
and that provides us with a space resolution
100
00:05:33,960 --> 00:05:36,723
of 140-meter telescope.
101
00:05:38,520 --> 00:05:39,840
With their equipment,
102
00:05:39,840 --> 00:05:44,840
the scientists can now not only detect, but image planets.
103
00:05:45,090 --> 00:05:48,183
When the Sun sets, the magic begins.
104
00:05:49,050 --> 00:05:53,250
Laser beams are used to create artificial guide stars
105
00:05:53,250 --> 00:05:56,853
to correct the distortions caused by the Earth's atmosphere.
106
00:05:58,140 --> 00:05:59,460
In the night skies,
107
00:05:59,460 --> 00:06:03,030
the scientists are looking out for exoplanets,
108
00:06:03,030 --> 00:06:05,400
especially newborn ones
109
00:06:05,400 --> 00:06:08,040
as they might deliver important clues
110
00:06:08,040 --> 00:06:10,443
to understand how planets form.
111
00:06:11,910 --> 00:06:12,960
In the control room,
112
00:06:12,960 --> 00:06:15,690
Thomas Henning and his colleague are monitoring
113
00:06:15,690 --> 00:06:17,373
the telescope's measurements.
114
00:06:18,390 --> 00:06:23,390
So I think the telescope is ready to go.
115
00:06:23,730 --> 00:06:25,113
Okay, let's get started.
116
00:06:27,330 --> 00:06:30,390
At a distance of nearly 400 light years,
117
00:06:30,390 --> 00:06:34,050
the astronomers have identified a young star.
118
00:06:34,050 --> 00:06:35,220
In its vicinity,
119
00:06:35,220 --> 00:06:39,600
they are now trying to capture an image of an exoplanet.
120
00:06:39,600 --> 00:06:43,950
To do this, Thomas Henning is using a stiller coronagraph,
121
00:06:43,950 --> 00:06:47,760
an instrument that emulates a solar eclipse.
122
00:06:47,760 --> 00:06:51,090
It blocks out the bright direct light from the star
123
00:06:51,090 --> 00:06:54,540
so that nearby planets become visible.
124
00:06:54,540 --> 00:06:57,960
In 2018, the scientists finally succeeded
125
00:06:57,960 --> 00:07:00,273
in capturing an amazing image.
126
00:07:01,440 --> 00:07:05,610
For the first time, we could see a planetary system
127
00:07:05,610 --> 00:07:07,200
in its birth environment
128
00:07:07,200 --> 00:07:10,980
so we could practically study a baby planet.
129
00:07:10,980 --> 00:07:13,560
And this was a very emotional moment
130
00:07:13,560 --> 00:07:18,150
because I tried that for many years.
131
00:07:18,150 --> 00:07:20,160
The picture revealed a disc filled
132
00:07:20,160 --> 00:07:24,000
with gas and dust surrounding the infant planet,
133
00:07:24,000 --> 00:07:28,260
leftover material from the formation of the system's star.
134
00:07:28,260 --> 00:07:30,450
From the image, Professor Henning could tell
135
00:07:30,450 --> 00:07:33,360
that the baby planet was a gas giant
136
00:07:33,360 --> 00:07:36,480
at least five times the mass of Jupiter,
137
00:07:36,480 --> 00:07:39,150
the largest planet in our solar system.
138
00:07:39,150 --> 00:07:41,580
We could analyze its atmosphere,
139
00:07:41,580 --> 00:07:44,850
and everything points to an atmosphere which is very dusty,
140
00:07:44,850 --> 00:07:46,140
which actually has clouds.
141
00:07:46,140 --> 00:07:48,270
So it must be something similar
142
00:07:48,270 --> 00:07:51,300
to the desert here when we have wind.
143
00:07:51,300 --> 00:07:53,580
The picture also tells Professor Henning
144
00:07:53,580 --> 00:07:55,530
something about the dramatic past
145
00:07:55,530 --> 00:07:58,620
of the exoplanet and its system.
146
00:07:58,620 --> 00:08:00,810
Because of its massive gravity,
147
00:08:00,810 --> 00:08:03,960
the planet sucks in everything in its path,
148
00:08:03,960 --> 00:08:06,330
forcing the region around its orbit
149
00:08:06,330 --> 00:08:09,183
to become devoid of gas and dust.
150
00:08:10,140 --> 00:08:13,830
The exoplanet shifts its orbit towards its star,
151
00:08:13,830 --> 00:08:17,520
sucking in even more material on its way.
152
00:08:17,520 --> 00:08:22,500
Any smaller objects it comes across are simply consumed,
153
00:08:22,500 --> 00:08:25,080
even other planets.
154
00:08:25,080 --> 00:08:26,520
We see this black stuff here,
155
00:08:26,520 --> 00:08:29,310
and this is caused by the fact
156
00:08:29,310 --> 00:08:33,090
that these giant planets clean everything
157
00:08:33,090 --> 00:08:36,450
so there is no other planets in a catastrophic way.
158
00:08:36,450 --> 00:08:39,903
They remove all the material from the disc.
159
00:08:42,060 --> 00:08:45,060
Since the detection of the first exoplanet,
160
00:08:45,060 --> 00:08:47,280
thousands of them have now been found
161
00:08:47,280 --> 00:08:49,113
in our own galaxy alone.
162
00:08:51,390 --> 00:08:53,280
By witnessing the birth of a planet
163
00:08:53,280 --> 00:08:55,050
for the first time in history,
164
00:08:55,050 --> 00:08:59,850
Professor Henning and his team have gathered important data.
165
00:08:59,850 --> 00:09:04,080
Our exoplanet research now paves the way to answer three
166
00:09:04,080 --> 00:09:08,010
of the most fundamental questions mankind can ask.
167
00:09:08,010 --> 00:09:11,370
First, are we actually alone in the universe?
168
00:09:11,370 --> 00:09:13,950
Is there life somewhere else?
169
00:09:13,950 --> 00:09:17,030
Second, how did life actually form
170
00:09:17,030 --> 00:09:18,663
in the early history of Earth?
171
00:09:19,685 --> 00:09:23,550
And the third question we can also ask and answer,
172
00:09:23,550 --> 00:09:25,560
how did Earth form
173
00:09:25,560 --> 00:09:28,413
and how did our planetary system came about?
174
00:09:30,090 --> 00:09:31,800
It is still miraculous
175
00:09:31,800 --> 00:09:35,040
how our planet has grown from stardust
176
00:09:35,040 --> 00:09:37,113
to a place fit for life.
177
00:09:38,070 --> 00:09:40,050
But the latest scientific discoveries
178
00:09:40,050 --> 00:09:42,050
have shed more and more light
179
00:09:42,050 --> 00:09:44,103
on how this could have happened.
180
00:09:47,280 --> 00:09:49,020
The formation of our world
181
00:09:49,020 --> 00:09:51,630
and the emergence of life are mysteries
182
00:09:51,630 --> 00:09:53,613
that scientists are trying to solve.
183
00:09:54,570 --> 00:09:57,930
Laura Kreidberg from the Max Planck Institute for Astronomy
184
00:09:57,930 --> 00:10:02,310
in Germany is passionate about finding these answers.
185
00:10:02,310 --> 00:10:04,860
Since her childhood, she has been fascinated
186
00:10:04,860 --> 00:10:06,933
by the vastness of the cosmos.
187
00:10:07,890 --> 00:10:09,450
One of the things I asked my mom
188
00:10:09,450 --> 00:10:11,610
when I was very young was,
189
00:10:11,610 --> 00:10:13,800
where is the edge of the universe?
190
00:10:13,800 --> 00:10:16,110
And she didn't know the answer,
191
00:10:16,110 --> 00:10:19,480
but I've been asking these questions ever since.
192
00:10:19,480 --> 00:10:21,900
(somber music)
193
00:10:21,900 --> 00:10:25,650
For me, looking in the night sky really puts our life
194
00:10:25,650 --> 00:10:27,750
on Earth in context.
195
00:10:27,750 --> 00:10:30,360
We know now that almost every other star
196
00:10:30,360 --> 00:10:32,970
in the sky has at least one planet,
197
00:10:32,970 --> 00:10:35,430
and when you get to see all of them up there,
198
00:10:35,430 --> 00:10:37,620
twinkling at us, you can imagine
199
00:10:37,620 --> 00:10:39,840
that perhaps there's an Earth-like planet
200
00:10:39,840 --> 00:10:41,910
with people on it wondering about us,
201
00:10:41,910 --> 00:10:43,910
just the way we would wonder about them.
202
00:10:44,940 --> 00:10:48,810
Whether we are alone is still unclear,
203
00:10:48,810 --> 00:10:52,200
but how our Earth evolved into the place it is today
204
00:10:52,200 --> 00:10:55,410
is only just beginning to be unraveled.
205
00:10:55,410 --> 00:10:57,660
The exploration of our solar system
206
00:10:57,660 --> 00:11:00,360
brings researchers one step closer
207
00:11:00,360 --> 00:11:01,923
to solving this mystery.
208
00:11:02,880 --> 00:11:04,980
To understand how our home,
209
00:11:04,980 --> 00:11:08,040
a small, rocky planet third from the Sun,
210
00:11:08,040 --> 00:11:10,410
became a place fit for life,
211
00:11:10,410 --> 00:11:13,860
we need to go back in time to the beginning,
212
00:11:13,860 --> 00:11:16,443
over 4 1/2 billion years ago.
213
00:11:19,620 --> 00:11:22,740
Scientists believe that our solar system begins
214
00:11:22,740 --> 00:11:26,790
as a vast interstellar cloud of gas and dust,
215
00:11:26,790 --> 00:11:30,210
twisting through the universe without direction.
216
00:11:30,210 --> 00:11:33,810
Eventually, the cloud collapses in on itself
217
00:11:33,810 --> 00:11:36,513
after becoming gravitationally unstable,
218
00:11:37,380 --> 00:11:39,360
forming a solar nebula,
219
00:11:39,360 --> 00:11:41,853
a spinning, swirling disc of material.
220
00:11:43,410 --> 00:11:45,600
And what tends to happen is
221
00:11:45,600 --> 00:11:49,650
that whatever random motions existed at the beginning,
222
00:11:49,650 --> 00:11:53,730
those are preserved so you hold on to the rotation.
223
00:11:53,730 --> 00:11:56,850
But the up and down motion cancels out.
224
00:11:56,850 --> 00:11:59,880
Material moving down collides with material moving up,
225
00:11:59,880 --> 00:12:02,850
and so that flattens the disc over time
226
00:12:02,850 --> 00:12:06,630
and you're left with this rotating flat disc
227
00:12:06,630 --> 00:12:08,073
that the planets form in.
228
00:12:09,630 --> 00:12:11,220
At the center of the disc,
229
00:12:11,220 --> 00:12:13,593
gravity pulls everything inward.
230
00:12:14,820 --> 00:12:17,790
The material at the center got hotter and hotter
231
00:12:17,790 --> 00:12:19,590
and higher and higher pressure,
232
00:12:19,590 --> 00:12:23,070
and eventually reached a point where the density
233
00:12:23,070 --> 00:12:25,590
and the temperature and the pressure were so high
234
00:12:25,590 --> 00:12:27,903
that hydrogen began to fuse in the core.
235
00:12:29,010 --> 00:12:31,740
With the pressure in the core so immense,
236
00:12:31,740 --> 00:12:35,460
hydrogen atoms begin to combine and form helium,
237
00:12:35,460 --> 00:12:38,133
releasing a tremendous amount of energy.
238
00:12:39,750 --> 00:12:42,120
This is some of the most dramatic events
239
00:12:42,120 --> 00:12:44,520
in the history of a solar system.
240
00:12:44,520 --> 00:12:47,523
With that, our Sun is born.
241
00:12:49,050 --> 00:12:51,570
A shining mass of chemical elements,
242
00:12:51,570 --> 00:12:54,990
forging light into the vast darkness.
243
00:12:54,990 --> 00:12:57,240
The temperature in the core of the Sun
244
00:12:57,240 --> 00:13:01,080
reaches more than 27 million degrees Fahrenheit,
245
00:13:01,080 --> 00:13:04,710
driven by internal nuclear reactions.
246
00:13:04,710 --> 00:13:07,170
It's been estimated every second
247
00:13:07,170 --> 00:13:11,643
the Sun produces more energy than a billion atomic bombs.
248
00:13:12,780 --> 00:13:16,980
The Sun accreted almost all of the gas surrounding it.
249
00:13:16,980 --> 00:13:20,130
99% of the material went into the Sun,
250
00:13:20,130 --> 00:13:22,110
but there was a little bit left over
251
00:13:22,110 --> 00:13:25,650
that formed a little proto-planetary disc.
252
00:13:25,650 --> 00:13:28,650
We call it a swirling cloud of gas and dust
253
00:13:28,650 --> 00:13:29,790
around the young star,
254
00:13:29,790 --> 00:13:31,740
and that's where the planets were born.
255
00:13:33,030 --> 00:13:34,860
The little material that remained
256
00:13:34,860 --> 00:13:37,350
around the heart of the new star was enough
257
00:13:37,350 --> 00:13:39,360
to form the raw ingredients
258
00:13:39,360 --> 00:13:42,903
for a new system of planets orbiting around the Sun.
259
00:13:43,770 --> 00:13:46,920
But how this material turned into planets
260
00:13:46,920 --> 00:13:49,369
has always been a subject of debate.
261
00:13:49,369 --> 00:13:51,810
(gentle music)
262
00:13:51,810 --> 00:13:53,460
One of the newest ideas about
263
00:13:53,460 --> 00:13:55,950
how planets form is called pebble accretion.
264
00:13:55,950 --> 00:13:58,560
And with this idea, the planets are growing out
265
00:13:58,560 --> 00:14:01,293
of small pebbles, so little bit at a time.
266
00:14:02,640 --> 00:14:05,220
Within the giant disc of gas and dust
267
00:14:05,220 --> 00:14:07,320
that circled the young star,
268
00:14:07,320 --> 00:14:10,950
particles smaller than the width of a human hair
269
00:14:10,950 --> 00:14:14,310
started to clump together and coalesce.
270
00:14:14,310 --> 00:14:17,790
By this, they grew into larger and larger pebbles,
271
00:14:17,790 --> 00:14:20,730
which started to collide with each other.
272
00:14:20,730 --> 00:14:22,770
It's a process that can be compared
273
00:14:22,770 --> 00:14:25,980
to colliding bumper cars at the amusement park.
274
00:14:25,980 --> 00:14:28,320
In the young solar system, there was a lot of material
275
00:14:28,320 --> 00:14:30,240
that was bumping into each other,
276
00:14:30,240 --> 00:14:33,360
exactly like these bumper cars are bumping into each other.
277
00:14:33,360 --> 00:14:36,450
But eventually, with bumper cars,
278
00:14:36,450 --> 00:14:38,133
you bump and you separate.
279
00:14:40,380 --> 00:14:43,260
But when planets form, the material is actually able
280
00:14:43,260 --> 00:14:46,260
to stick together and grow to form the planets we see today.
281
00:14:47,190 --> 00:14:48,863
Just like when the bumper cars come together
282
00:14:48,863 --> 00:14:51,137
and the one in the middle can't escape.
283
00:14:52,587 --> 00:14:53,940
Escape from these collisions,
284
00:14:53,940 --> 00:14:57,930
pebbles eventually grew into gigantic bodies of rock,
285
00:14:57,930 --> 00:15:01,110
some the size of the biggest asteroids we find
286
00:15:01,110 --> 00:15:02,733
in the solar system today.
287
00:15:04,320 --> 00:15:07,650
Eventually, some of these objects became large enough
288
00:15:07,650 --> 00:15:11,100
to take on a spherical shape under the influence
289
00:15:11,100 --> 00:15:12,303
of their own gravity.
290
00:15:13,230 --> 00:15:15,840
At this stage, these protoplanets started
291
00:15:15,840 --> 00:15:19,470
to grow faster and faster by consuming all the material
292
00:15:19,470 --> 00:15:21,243
in their orbit around the Sun.
293
00:15:25,440 --> 00:15:28,620
And these pebbles are able to be vacuumed
294
00:15:28,620 --> 00:15:31,500
into the young, growing planet very, very quickly,
295
00:15:31,500 --> 00:15:35,070
very efficiently, so that we can grow very large planets
296
00:15:35,070 --> 00:15:38,703
on the short timescales that we observe around other stars.
297
00:15:39,930 --> 00:15:42,420
Growing planets is not unlike
298
00:15:42,420 --> 00:15:44,019
making cotton candy.
299
00:15:44,019 --> 00:15:46,602
(gentle music)
300
00:15:49,800 --> 00:15:54,330
And now watching this cotton candy slowly grow up
301
00:15:54,330 --> 00:15:57,030
into a big ball, it's almost exactly the same
302
00:15:57,030 --> 00:16:00,600
as a protoplanet accreting more and more gas and dust
303
00:16:00,600 --> 00:16:03,300
as it moves through the proto-planetary disc.
304
00:16:03,300 --> 00:16:04,620
As it moves through its orbit,
305
00:16:04,620 --> 00:16:07,470
you can see it growing larger and larger and larger
306
00:16:07,470 --> 00:16:11,040
until, at the very end, you have a giant planet,
307
00:16:11,040 --> 00:16:12,897
or perhaps cotton candy.
308
00:16:12,897 --> 00:16:15,461
(awe-inspiring music)
309
00:16:15,461 --> 00:16:19,044
(Laura speaking in German)
310
00:16:24,510 --> 00:16:26,640
The newly-born planets are anchored
311
00:16:26,640 --> 00:16:28,440
by the gravity of the Sun,
312
00:16:28,440 --> 00:16:31,480
which they orbit in various paths.
313
00:16:31,480 --> 00:16:34,290
It is this gravity that keeps these protoplanets
314
00:16:34,290 --> 00:16:38,013
from flying off into the universe or collapsing together.
315
00:16:39,289 --> 00:16:43,110
In the outer solar system, our biggest planets are formed.
316
00:16:43,110 --> 00:16:46,860
They absorb all the gas within the proto-planetary disc,
317
00:16:46,860 --> 00:16:51,860
becoming the gas giants, Jupiter and Saturn,
318
00:16:51,930 --> 00:16:56,853
and the far away ice giants, Uranus and Neptune.
319
00:16:58,500 --> 00:17:00,960
Without any gas left in the disc,
320
00:17:00,960 --> 00:17:04,740
the protoplanets in the inner solar system remain rocky
321
00:17:04,740 --> 00:17:06,750
and relatively small,
322
00:17:06,750 --> 00:17:08,970
becoming terrestrial planets
323
00:17:08,970 --> 00:17:13,970
like Mercury, closest to the Sun, Venus, and Mars.
324
00:17:15,480 --> 00:17:18,930
We think that planet formation happens pretty quickly.
325
00:17:18,930 --> 00:17:20,580
So after the star forms
326
00:17:20,580 --> 00:17:23,400
and there's this disc of material around it,
327
00:17:23,400 --> 00:17:25,770
after not even 10 million years,
328
00:17:25,770 --> 00:17:28,770
the planets can be fully formed after that.
329
00:17:28,770 --> 00:17:30,210
And that's just the blink of an eye
330
00:17:30,210 --> 00:17:32,163
in the length of the solar system.
331
00:17:33,120 --> 00:17:35,010
One of those planets has formed
332
00:17:35,010 --> 00:17:38,733
between Venus and Mars, Earth,
333
00:17:39,780 --> 00:17:43,800
born from tiny dust particles like its cousins.
334
00:17:43,800 --> 00:17:47,400
But it's not the blue planet we know today.
335
00:17:47,400 --> 00:17:50,853
Earth is a spinning of red hot rock.
336
00:17:51,720 --> 00:17:53,430
Our barren planet looks
337
00:17:53,430 --> 00:17:57,003
like it could not contain anything related to life.
338
00:17:59,190 --> 00:18:01,710
The Earth during its very early lifetime
339
00:18:01,710 --> 00:18:04,740
was not a friendly place for life at all.
340
00:18:04,740 --> 00:18:07,620
Imagine yourself standing on top
341
00:18:07,620 --> 00:18:10,680
of the early Earth just after it formed.
342
00:18:10,680 --> 00:18:12,450
This is not a happy place to be.
343
00:18:12,450 --> 00:18:14,580
It is excruciatingly hot.
344
00:18:14,580 --> 00:18:17,280
The surface is so hot that it's molten lava.
345
00:18:17,280 --> 00:18:19,230
You would not survive very long,
346
00:18:19,230 --> 00:18:20,973
but that is not your only problem.
347
00:18:22,230 --> 00:18:24,450
4 1/2 billion years ago,
348
00:18:24,450 --> 00:18:28,473
the solar system was vastly different from what it is today.
349
00:18:29,400 --> 00:18:32,550
Not only was the young Earth extremely hot,
350
00:18:32,550 --> 00:18:35,280
extremely inhospitable to life as we know it,
351
00:18:35,280 --> 00:18:38,253
but it was about to face a very enormous challenge.
352
00:18:39,630 --> 00:18:42,990
A catastrophic event was about to take place
353
00:18:42,990 --> 00:18:46,453
that would change the history of Earth forever.
354
00:18:46,453 --> 00:18:49,120
(ominous music)
355
00:18:50,978 --> 00:18:53,760
(gentle music)
356
00:18:53,760 --> 00:18:56,490
It is the Moon that provides us with evidence
357
00:18:56,490 --> 00:18:58,143
of this first catastrophe.
358
00:18:58,980 --> 00:19:02,640
In 1969, the Apollo 11 mission brought back
359
00:19:02,640 --> 00:19:05,850
the first moon rock samples to earth.
360
00:19:05,850 --> 00:19:09,540
Since then, NASA has retrieved thousands of samples
361
00:19:09,540 --> 00:19:10,713
on their missions.
362
00:19:11,550 --> 00:19:14,940
Because the Moon, unlike our Earth, hasn't changed
363
00:19:14,940 --> 00:19:17,190
as much since its formation,
364
00:19:17,190 --> 00:19:19,500
these samples can help unravel
365
00:19:19,500 --> 00:19:21,993
how the past has shaped our present,
366
00:19:22,830 --> 00:19:25,050
holding the key to the mysteries
367
00:19:25,050 --> 00:19:28,233
of the emergence of the Moon and the Earth alike.
368
00:19:31,500 --> 00:19:32,793
Zurich, Switzerland.
369
00:19:34,070 --> 00:19:37,620
Every year, NASA distributes some of their moon samples
370
00:19:37,620 --> 00:19:40,683
to a select group of scientists around the world.
371
00:19:42,690 --> 00:19:44,430
Professor Maria Schonbachler
372
00:19:44,430 --> 00:19:47,310
at the Swiss Federal Institute of Technology
373
00:19:47,310 --> 00:19:49,113
is one of those recipients.
374
00:19:54,180 --> 00:19:56,070
They are much more valuable than gold.
375
00:19:56,070 --> 00:20:00,630
So a gram like that is about 10 or 20 times more valuable.
376
00:20:00,630 --> 00:20:02,460
The lunar surface is very old
377
00:20:02,460 --> 00:20:04,770
and has hardly changed compared to the Earth,
378
00:20:04,770 --> 00:20:06,840
and that helps us decipher the secrets
379
00:20:06,840 --> 00:20:09,240
of the early Earth and the early Moon.
380
00:20:09,240 --> 00:20:11,820
The Moon is like a window back into the past,
381
00:20:11,820 --> 00:20:13,443
and I find that fascinating.
382
00:20:15,870 --> 00:20:17,850
Professor Schonbachler is looking
383
00:20:17,850 --> 00:20:21,450
for particular chemical signatures in the lunar rocks
384
00:20:21,450 --> 00:20:24,363
that might reveal clues about their origins.
385
00:20:25,200 --> 00:20:28,680
In an experiment, she now wants to compare the composition
386
00:20:28,680 --> 00:20:31,323
of the Moon to the composition of Earth.
387
00:20:33,630 --> 00:20:36,660
Here we have a dissolved sample of the Moon
388
00:20:36,660 --> 00:20:38,733
and this is an Earth sample from Hawaii.
389
00:20:41,250 --> 00:20:42,720
Now we can analyze these
390
00:20:42,720 --> 00:20:45,543
and see how closely related Earth and Moon are.
391
00:20:48,420 --> 00:20:50,520
Using isotope analysis,
392
00:20:50,520 --> 00:20:54,600
Maria can compare the samples on an atomic level.
393
00:20:54,600 --> 00:20:57,270
She's particularly struck by the composition
394
00:20:57,270 --> 00:21:00,180
of the respective chromium isotopes.
395
00:21:00,180 --> 00:21:02,403
The measured values are astounding.
396
00:21:04,170 --> 00:21:05,910
What we see here are the measurements
397
00:21:05,910 --> 00:21:08,103
from the Earth sample and the Moon sample.
398
00:21:09,030 --> 00:21:10,950
All the bars are identical.
399
00:21:10,950 --> 00:21:12,000
That means the Earth
400
00:21:12,000 --> 00:21:15,060
and the Moon have exactly the same fingerprint,
401
00:21:15,060 --> 00:21:19,110
and that in turn tells us they must be very closely related.
402
00:21:19,110 --> 00:21:22,980
So the Earth and the Moon are geological twins.
403
00:21:22,980 --> 00:21:25,683
The question now is, how did that come about?
404
00:21:29,880 --> 00:21:31,380
There are multiple theories
405
00:21:31,380 --> 00:21:33,990
about how the Moon was formed.
406
00:21:33,990 --> 00:21:36,660
The results of the analysis suggest
407
00:21:36,660 --> 00:21:39,030
that its formation is closely linked
408
00:21:39,030 --> 00:21:40,833
to the history of Earth.
409
00:21:43,080 --> 00:21:45,660
People have wondered for a really long time
410
00:21:45,660 --> 00:21:48,233
how Earth's moon formed, and there have been a lot
411
00:21:48,233 --> 00:21:50,400
of different ideas how it happened.
412
00:21:50,400 --> 00:21:54,120
One of them was that the Moon actually was a little piece
413
00:21:54,120 --> 00:21:56,520
of the Earth that got broken off early
414
00:21:56,520 --> 00:21:58,563
in the lifetime of the planet.
415
00:21:59,790 --> 00:22:01,740
Another idea was that the Earth
416
00:22:01,740 --> 00:22:04,110
and Moon actually formed at the same time
417
00:22:04,110 --> 00:22:08,220
from the proto-planetary disc, like a little binary system.
418
00:22:08,220 --> 00:22:11,790
But the theory that has the most support now
419
00:22:11,790 --> 00:22:14,433
is actually much more spectacular.
420
00:22:17,910 --> 00:22:20,340
4.5 billion years ago,
421
00:22:20,340 --> 00:22:24,390
planetary embryos were circling around the Sun,
422
00:22:24,390 --> 00:22:27,060
together with a countless number of smaller
423
00:22:27,060 --> 00:22:29,373
but still huge chunks of rocks.
424
00:22:30,240 --> 00:22:33,723
The early solar system was a hazardous place.
425
00:22:37,560 --> 00:22:40,773
Maria Schonbachler can read this in the Moon's surface.
426
00:22:42,540 --> 00:22:44,430
The exciting thing about the Moon is
427
00:22:44,430 --> 00:22:46,950
that its surface is very old.
428
00:22:46,950 --> 00:22:50,190
That means if we study the Moon, we also study the history
429
00:22:50,190 --> 00:22:52,773
of the Earth because it's a mirror image.
430
00:22:53,730 --> 00:22:56,070
And if we now look at the surface of the Moon
431
00:22:56,070 --> 00:22:58,050
and see all these craters,
432
00:22:58,050 --> 00:23:00,630
some of which are also extremely old,
433
00:23:00,630 --> 00:23:02,460
then we know that early Earth
434
00:23:02,460 --> 00:23:07,230
also suffered many impacts from asteroids or comets,
435
00:23:07,230 --> 00:23:08,283
just like the Moon.
436
00:23:10,170 --> 00:23:12,240
Just after the planets formed,
437
00:23:12,240 --> 00:23:15,390
the solar system was a very dangerous place to be.
438
00:23:15,390 --> 00:23:17,940
There was material leftover from planet formation
439
00:23:17,940 --> 00:23:19,350
that was flying around.
440
00:23:19,350 --> 00:23:20,820
Collisions were common,
441
00:23:20,820 --> 00:23:22,920
and the Earth was about to experience one
442
00:23:22,920 --> 00:23:26,553
of the most catastrophic collisions in its entire history.
443
00:23:27,450 --> 00:23:30,030
In the early days of our solar system,
444
00:23:30,030 --> 00:23:32,193
Earth was being bombarded.
445
00:23:34,380 --> 00:23:37,020
The young solar system was a very violent place
446
00:23:37,020 --> 00:23:38,733
and collisions were common.
447
00:23:41,010 --> 00:23:43,170
But the most apocalyptic collision
448
00:23:43,170 --> 00:23:46,563
in the history of our Earth was about to take place.
449
00:23:49,080 --> 00:23:53,100
At this time, Earth was an ocean of molten lava,
450
00:23:53,100 --> 00:23:55,170
hundreds of miles in depth,
451
00:23:55,170 --> 00:23:57,360
perpetually stirred up by the impacts
452
00:23:57,360 --> 00:23:59,283
of asteroids and comets.
453
00:24:00,210 --> 00:24:02,913
It had nearly reached its final size,
454
00:24:04,740 --> 00:24:07,950
but approaching from the dark void was Theia,
455
00:24:07,950 --> 00:24:11,313
a massive protoplanet the size of Mars.
456
00:24:12,150 --> 00:24:14,520
Like Earth, it had been growing quickly
457
00:24:14,520 --> 00:24:17,460
by consuming everything in its path
458
00:24:17,460 --> 00:24:20,746
and now it was heading straight for Earth.
459
00:24:20,746 --> 00:24:23,413
(ominous music)
460
00:24:25,955 --> 00:24:28,705
(impact booming)
461
00:24:33,060 --> 00:24:36,393
The impact of Theia nearly destroyed Earth.
462
00:24:37,260 --> 00:24:40,050
Vaporized chunks of our young planet's crust
463
00:24:40,050 --> 00:24:41,703
were thrown into space.
464
00:24:45,690 --> 00:24:49,140
The scale of this impact is hard to even imagine.
465
00:24:49,140 --> 00:24:52,500
It was a hundred million times larger
466
00:24:52,500 --> 00:24:55,770
than the impact to Earth that we think killed the dinosaurs.
467
00:24:55,770 --> 00:25:00,030
The impact was so strong that Theia was obliterated,
468
00:25:00,030 --> 00:25:04,440
and what was left over was chunks of both Theia
469
00:25:04,440 --> 00:25:06,420
and the surface of the Earth
470
00:25:06,420 --> 00:25:10,200
that were ejected into orbit around Earth itself
471
00:25:10,200 --> 00:25:12,183
and were held in by Earth's gravity.
472
00:25:15,450 --> 00:25:18,540
That debris cloud flattened into a disc,
473
00:25:18,540 --> 00:25:21,960
not so different from the original disc around the young Sun
474
00:25:21,960 --> 00:25:23,550
where the first planets formed.
475
00:25:23,550 --> 00:25:26,430
As material orbited around the young Earth,
476
00:25:26,430 --> 00:25:28,380
you had small pebbles, small grains,
477
00:25:28,380 --> 00:25:30,603
bumping into each other that grew and grew.
478
00:25:32,670 --> 00:25:35,370
Gas, dust, and rock coalesced
479
00:25:35,370 --> 00:25:39,063
into a spherical shape that continued to orbit Earth.
480
00:25:39,930 --> 00:25:43,833
A new world was created, the Moon.
481
00:25:45,270 --> 00:25:47,793
But it was far from the one we know today.
482
00:25:48,990 --> 00:25:50,670
Right after its formation,
483
00:25:50,670 --> 00:25:53,160
the Moon was about 17 times closer
484
00:25:53,160 --> 00:25:55,473
to our planet than it is today.
485
00:25:56,310 --> 00:26:00,300
Its proximity to Earth had dire consequences,
486
00:26:00,300 --> 00:26:02,490
bringing violent instability
487
00:26:02,490 --> 00:26:04,743
to the molten planet it orbited.
488
00:26:05,760 --> 00:26:08,493
Earth had passed its baptism of fire.
489
00:26:09,660 --> 00:26:12,660
But even a long time after the impact,
490
00:26:12,660 --> 00:26:15,060
our planet was far from being a place
491
00:26:15,060 --> 00:26:16,833
where life could emerge.
492
00:26:21,060 --> 00:26:22,680
How this happened is one
493
00:26:22,680 --> 00:26:24,720
of the key questions that scientists
494
00:26:24,720 --> 00:26:27,720
at the Max Planck Institute for Solar System Research
495
00:26:27,720 --> 00:26:30,153
in Gottingen, Germany want to answer.
496
00:26:31,200 --> 00:26:34,200
One of them is Dr. Fred Goesmann.
497
00:26:34,200 --> 00:26:37,320
He participated in the European Space Agency's
498
00:26:37,320 --> 00:26:41,220
Rosetta Mission, where a probe was sent to a comet
499
00:26:41,220 --> 00:26:45,270
to look for earliest traces of life in our solar system.
500
00:26:45,270 --> 00:26:46,830
People came up with the idea in Europe,
501
00:26:46,830 --> 00:26:48,120
let's fly to a comet.
502
00:26:48,120 --> 00:26:52,080
Let's not just fly past it, let's go to the comet,
503
00:26:52,080 --> 00:26:54,900
orbit it, land on it, and see what it's made of.
504
00:26:54,900 --> 00:26:57,960
And so the question is, did comets bring something
505
00:26:57,960 --> 00:27:00,273
which helped for life to emerge on Earth?
506
00:27:01,530 --> 00:27:06,330
The comet known as 67P/Churyumov-Gerasimenko
507
00:27:06,330 --> 00:27:08,880
was on an elliptical journey stretching
508
00:27:08,880 --> 00:27:10,920
between Jupiter at one end
509
00:27:10,920 --> 00:27:14,670
and the region between Earth and Mars at the other.
510
00:27:14,670 --> 00:27:18,690
The plan was for the Rosetta probe to travel with the comet,
511
00:27:18,690 --> 00:27:21,720
before dispatching a lander to the comet's surface
512
00:27:21,720 --> 00:27:23,613
to collect invaluable data.
513
00:27:24,510 --> 00:27:27,060
Fred Goesmann developed a special instrument
514
00:27:27,060 --> 00:27:29,010
for Rosetta's lander, Philae,
515
00:27:29,010 --> 00:27:32,580
that's capable of measuring the properties of the comet.
516
00:27:32,580 --> 00:27:36,330
Philae is a little bit of a small beast landing on a comet
517
00:27:36,330 --> 00:27:38,100
and it has eyes, which are the camera,
518
00:27:38,100 --> 00:27:41,430
it's got a sense of feeling, which is the feet,
519
00:27:41,430 --> 00:27:42,990
and this thing was the nose.
520
00:27:42,990 --> 00:27:44,190
It is a chemical instrument.
521
00:27:44,190 --> 00:27:45,780
It's sniffing for molecules
522
00:27:45,780 --> 00:27:48,933
and identifying them by technical means.
523
00:27:49,800 --> 00:27:53,010
In 2004, the Rosetta probe was launched
524
00:27:53,010 --> 00:27:55,860
on its billion-kilometer journey.
525
00:27:55,860 --> 00:27:57,960
After a flight of 10 years,
526
00:27:57,960 --> 00:28:01,770
the spacecraft finally reached its destination.
527
00:28:01,770 --> 00:28:05,460
The optical instruments onboard Rosetta catched a glimpse
528
00:28:05,460 --> 00:28:07,173
of the strange looking comet.
529
00:28:09,660 --> 00:28:12,030
And it slowly grew in size, and you saw,
530
00:28:12,030 --> 00:28:14,460
oh no, it looks like a rubber duck.
531
00:28:14,460 --> 00:28:16,893
And it was pretty clear, don't call it a duck.
532
00:28:17,850 --> 00:28:22,110
Rosetta entered the orbit of Comet 67P.
533
00:28:22,110 --> 00:28:25,443
Then, Philae was released to land on the surface.
534
00:28:29,220 --> 00:28:31,980
The landing itself was really exciting.
535
00:28:31,980 --> 00:28:34,200
We saw images of the camera system of the orbiter
536
00:28:34,200 --> 00:28:35,520
that the legs had unfolded.
537
00:28:35,520 --> 00:28:36,353
It worked.
538
00:28:36,353 --> 00:28:37,770
The legs were nicely spread out,
539
00:28:37,770 --> 00:28:41,130
and so the thing came down and then we heard touchdown.
540
00:28:41,130 --> 00:28:42,600
We are on ground.
541
00:28:42,600 --> 00:28:44,640
People at ESA were cheering and everything,
542
00:28:44,640 --> 00:28:47,190
and then the engineers scratched their heads
543
00:28:47,190 --> 00:28:50,790
and said, no, it's moving.
544
00:28:50,790 --> 00:28:52,390
And that was really frightening.
545
00:28:53,430 --> 00:28:55,170
The landing gear did not appear
546
00:28:55,170 --> 00:28:56,763
to be working as planned.
547
00:28:58,530 --> 00:29:03,030
What we have here is one of the three landing legs.
548
00:29:03,030 --> 00:29:05,460
So in order to stay on the cometary surface,
549
00:29:05,460 --> 00:29:07,800
which we already knew would be very difficult,
550
00:29:07,800 --> 00:29:12,060
we gave this lander harpoons, claws, teeth, everything.
551
00:29:12,060 --> 00:29:13,830
And this is one of the feet.
552
00:29:13,830 --> 00:29:16,470
When these paws touch the surface
553
00:29:16,470 --> 00:29:19,770
and they experience a force, are being pushed back,
554
00:29:19,770 --> 00:29:23,100
they could retract and push forward,
555
00:29:23,100 --> 00:29:24,930
we called it an ice screw.
556
00:29:24,930 --> 00:29:28,170
The idea was, well, you touch the surface
557
00:29:28,170 --> 00:29:29,700
and you recognize that
558
00:29:29,700 --> 00:29:32,610
by some motion in the mechanical system.
559
00:29:32,610 --> 00:29:35,460
And once that happened, you fire harpoons into the comet
560
00:29:35,460 --> 00:29:36,720
and then you secure everything.
561
00:29:36,720 --> 00:29:39,780
You pull the rope of the harpoon and everything.
562
00:29:39,780 --> 00:29:40,613
Nope.
563
00:29:41,730 --> 00:29:43,920
The harpoons that should anchor Philae
564
00:29:43,920 --> 00:29:46,113
to the landing spot failed.
565
00:29:46,980 --> 00:29:49,590
Untethered, Philae bounced off the comet
566
00:29:49,590 --> 00:29:51,540
for the next two hours.
567
00:29:51,540 --> 00:29:55,023
Finally, the lander settled in the shadow of a cliff.
568
00:29:56,340 --> 00:30:00,000
The final position where it came to rest was so awkward.
569
00:30:00,000 --> 00:30:01,500
It wasn't standing on its legs.
570
00:30:01,500 --> 00:30:02,850
It was kind of up way,
571
00:30:02,850 --> 00:30:05,370
one leg was really pointing upwards.
572
00:30:05,370 --> 00:30:08,670
The drill was kind of poking into nowhere.
573
00:30:08,670 --> 00:30:10,023
It didn't reach the ground.
574
00:30:11,310 --> 00:30:13,710
So it did all its motions,
575
00:30:13,710 --> 00:30:15,180
but it didn't give us a sample
576
00:30:15,180 --> 00:30:18,900
because it couldn't touch anything.
577
00:30:18,900 --> 00:30:21,060
It seemed that the billion-dollar mission
578
00:30:21,060 --> 00:30:25,650
to find out more about the origin of life had failed.
579
00:30:25,650 --> 00:30:30,270
But despite things not going to plan, samples were taken.
580
00:30:30,270 --> 00:30:33,420
We were a bit fortunate because we hit the ground,
581
00:30:33,420 --> 00:30:35,460
and obviously stuff was excavated
582
00:30:35,460 --> 00:30:37,650
and there was a plume of something coming up.
583
00:30:37,650 --> 00:30:39,510
And this very initial measurement
584
00:30:39,510 --> 00:30:41,370
where we just switch on the mass spectrometer
585
00:30:41,370 --> 00:30:43,830
to see what the environment tells us,
586
00:30:43,830 --> 00:30:47,100
only these two tiny minutes of measurements
587
00:30:47,100 --> 00:30:49,080
gave us a brilliant spectrum.
588
00:30:49,080 --> 00:30:50,580
For me, when I was seeing it,
589
00:30:50,580 --> 00:30:53,397
it was the most sexy mass spectrum in the world,
590
00:30:53,397 --> 00:30:55,200
and it still is.
591
00:30:55,200 --> 00:30:56,880
After a thorough analysis
592
00:30:56,880 --> 00:31:00,990
of the measurements, the comet's properties were revealed.
593
00:31:00,990 --> 00:31:05,700
It contained carbon, hydrogen, oxygen, nitrogen,
594
00:31:05,700 --> 00:31:06,993
and even more.
595
00:31:08,550 --> 00:31:10,950
We found molecules, organic molecules.
596
00:31:10,950 --> 00:31:13,020
And if you put them in the right environment,
597
00:31:13,020 --> 00:31:15,180
they would be suitable to combine
598
00:31:15,180 --> 00:31:17,893
and to build anything you need in order to have life.
599
00:31:17,893 --> 00:31:20,400
I would say that if you have a planet
600
00:31:20,400 --> 00:31:21,930
and many comets fall onto it
601
00:31:21,930 --> 00:31:24,030
and they are of such composition,
602
00:31:24,030 --> 00:31:25,800
it would create an environment
603
00:31:25,800 --> 00:31:28,143
which life would be happy to thrive on.
604
00:31:29,700 --> 00:31:31,380
Whether it was really comets
605
00:31:31,380 --> 00:31:34,920
that started life on Earth is debated,
606
00:31:34,920 --> 00:31:37,710
but even if they did deliver the building blocks,
607
00:31:37,710 --> 00:31:42,630
our planet needed a radical change to enable life to evolve.
608
00:31:42,630 --> 00:31:46,290
There was still another ingredient that was missing.
609
00:31:46,290 --> 00:31:47,123
Water.
610
00:31:48,660 --> 00:31:51,480
Comets like 67P originate
611
00:31:51,480 --> 00:31:55,680
from beyond the orbit of Neptune or even farther out
612
00:31:55,680 --> 00:32:00,360
and are supposed to carry a lot of water in the form of ice.
613
00:32:00,360 --> 00:32:02,640
Many scientists, therefore, believe
614
00:32:02,640 --> 00:32:05,703
that comets also brought water to Earth.
615
00:32:06,870 --> 00:32:10,470
High resolution images of comet 67P
616
00:32:10,470 --> 00:32:13,863
indeed show the presence of water ice on the surface,
617
00:32:14,790 --> 00:32:16,950
but the analysis of the atomic makeup
618
00:32:16,950 --> 00:32:19,800
of the comet water shows that it is different
619
00:32:19,800 --> 00:32:21,573
from the water we have on Earth.
620
00:32:22,500 --> 00:32:24,030
This means that water
621
00:32:24,030 --> 00:32:27,750
on Earth cannot have been delivered by comets.
622
00:32:27,750 --> 00:32:30,033
It must have come from somewhere else.
623
00:32:32,700 --> 00:32:35,400
On September 12th, 2019,
624
00:32:35,400 --> 00:32:39,540
more than 500 people along the North Sea coast reported
625
00:32:39,540 --> 00:32:42,660
seeing a strange phenomenon across the sky
626
00:32:42,660 --> 00:32:43,863
in broad daylight.
627
00:32:44,820 --> 00:32:46,890
While filming a selfie video,
628
00:32:46,890 --> 00:32:50,340
a kite surfer from Northern Germany captured the event
629
00:32:50,340 --> 00:32:54,120
in the background, a flash of bright light.
630
00:32:54,120 --> 00:32:57,633
It was a meteorite on its way down to Earth.
631
00:32:58,590 --> 00:33:00,890
Professor Thorsten Kleine, director
632
00:33:00,890 --> 00:33:04,380
of the Max Planck Institute for Solar System Research,
633
00:33:04,380 --> 00:33:06,000
wants to find out if this piece
634
00:33:06,000 --> 00:33:09,240
of rock can help solve the riddle of water.
635
00:33:09,240 --> 00:33:11,730
A day after the flash, a 25-gram piece
636
00:33:11,730 --> 00:33:15,090
of a meteorite has been found near Flensburg in Germany.
637
00:33:15,090 --> 00:33:17,820
It would've looked just like this, a black rock,
638
00:33:17,820 --> 00:33:19,350
not very spectacular looking,
639
00:33:19,350 --> 00:33:21,513
but scientifically extremely interesting.
640
00:33:22,890 --> 00:33:24,150
The analysis shows
641
00:33:24,150 --> 00:33:27,780
that the meteorite is nearly as old as the solar system,
642
00:33:27,780 --> 00:33:30,333
and that it is a piece from an asteroid.
643
00:33:31,230 --> 00:33:33,690
While comets are icy with tails
644
00:33:33,690 --> 00:33:36,270
and come from the outer solar system,
645
00:33:36,270 --> 00:33:39,000
asteroids are rocky and mainly stay
646
00:33:39,000 --> 00:33:41,853
in a belt between Mars and Jupiter.
647
00:33:43,170 --> 00:33:46,110
Because of their relative proximity to the Sun,
648
00:33:46,110 --> 00:33:49,170
they usually do not consist of ice.
649
00:33:49,170 --> 00:33:53,460
Nevertheless, the analysis in the lab shows Thorsten Kleine
650
00:33:53,460 --> 00:33:56,490
that they do carry a precious cargo.
651
00:33:56,490 --> 00:33:59,340
If you look into this, we can find hydrogen and oxygen,
652
00:33:59,340 --> 00:34:02,430
the building blocks of water, bound into minerals.
653
00:34:02,430 --> 00:34:05,610
But most importantly, we can also find the signature is the
654
00:34:05,610 --> 00:34:08,820
same as it is for water from the Earth.
655
00:34:08,820 --> 00:34:09,990
That means that the water
656
00:34:09,990 --> 00:34:12,603
on our planet might have come from asteroids.
657
00:34:13,590 --> 00:34:15,540
Further research also revealed
658
00:34:15,540 --> 00:34:19,200
that mineral-bound-water-containing asteroids initially came
659
00:34:19,200 --> 00:34:21,870
together to form our planet.
660
00:34:21,870 --> 00:34:23,940
This means water could have been on Earth
661
00:34:23,940 --> 00:34:27,453
from the beginning, albeit not in liquid form.
662
00:34:31,080 --> 00:34:33,660
But how did the mineral-bound water transform
663
00:34:33,660 --> 00:34:35,640
the hellish early Earth into something
664
00:34:35,640 --> 00:34:37,323
that could host life one day?
665
00:34:38,250 --> 00:34:39,810
Over millions of years,
666
00:34:39,810 --> 00:34:43,113
the hot molten planet cooled enough to form a crust.
667
00:34:44,070 --> 00:34:47,370
The heat below the surface released, amongst others,
668
00:34:47,370 --> 00:34:51,003
oxygen and hydrogen that was bound in the minerals.
669
00:34:51,960 --> 00:34:55,080
The out gassing formed an atmosphere.
670
00:34:55,080 --> 00:34:57,420
Water vapor condensed and fell
671
00:34:57,420 --> 00:34:59,643
onto the rocky planet as rain.
672
00:35:00,600 --> 00:35:02,940
It rained for millions of years,
673
00:35:02,940 --> 00:35:05,493
long enough to create the first oceans.
674
00:35:07,290 --> 00:35:10,440
The world that had once been a ball of fire
675
00:35:10,440 --> 00:35:13,143
had become a world of water.
676
00:35:14,910 --> 00:35:17,940
200 million years after its formation,
677
00:35:17,940 --> 00:35:20,970
Earth is covered with liquid water.
678
00:35:20,970 --> 00:35:24,540
But despite this, there is no life yet
679
00:35:24,540 --> 00:35:28,980
because our planet is still a hostile place.
680
00:35:28,980 --> 00:35:31,443
One reason for this is our Moon.
681
00:35:32,400 --> 00:35:34,800
The impact of Theia has caused Earth
682
00:35:34,800 --> 00:35:39,063
to become bound to a new moon, and this is causing havoc.
683
00:35:39,900 --> 00:35:43,860
Over 4 billion years ago, the Moon was very different
684
00:35:43,860 --> 00:35:45,213
to what it is today.
685
00:35:46,380 --> 00:35:49,500
Just after the Moon formed, it was much closer
686
00:35:49,500 --> 00:35:51,510
to the Earth than the Moon is today.
687
00:35:51,510 --> 00:35:53,340
More than 10 times closer.
688
00:35:53,340 --> 00:35:56,430
So it would've appeared very large in the sky,
689
00:35:56,430 --> 00:35:59,610
and not only that, but it would still be incredibly hot
690
00:35:59,610 --> 00:36:02,460
from the violent impact that formed it,
691
00:36:02,460 --> 00:36:04,440
and so it would be glowing.
692
00:36:04,440 --> 00:36:06,790
You'd be able to see it even during the daytime
693
00:36:08,284 --> 00:36:09,930
With an object this large
694
00:36:09,930 --> 00:36:11,520
and this close to Earth,
695
00:36:11,520 --> 00:36:14,283
cataclysmic effects shook our planet.
696
00:36:15,480 --> 00:36:18,030
The most important force that governs the motion
697
00:36:18,030 --> 00:36:20,580
of the Earth and Moon is gravity.
698
00:36:20,580 --> 00:36:22,740
The Earth is exerting a gravitational pull
699
00:36:22,740 --> 00:36:24,543
on the Moon and vice versa.
700
00:36:25,500 --> 00:36:27,420
Similarly, when you're on a carousel
701
00:36:27,420 --> 00:36:30,330
and you're moving quickly around the center,
702
00:36:30,330 --> 00:36:33,750
there's a centrifugal force that is pushing you outwards
703
00:36:33,750 --> 00:36:35,340
and that's the exact same force
704
00:36:35,340 --> 00:36:38,623
that would be at play with the Earth and the Moon.
705
00:36:38,623 --> 00:36:42,070
The moon tore at our young planet's surface.
706
00:36:44,460 --> 00:36:48,120
This was a very dramatic environment for the early Earth.
707
00:36:48,120 --> 00:36:52,380
The Moon's tidal forces were driving enormous waves
708
00:36:52,380 --> 00:36:55,290
in Earth's ocean, so every wave crashing on the shore
709
00:36:55,290 --> 00:36:57,390
would've been like a tsunami at that time.
710
00:36:58,770 --> 00:37:00,690
The world of water was shaken
711
00:37:00,690 --> 00:37:03,603
by the enormous force the Moon exerted.
712
00:37:04,470 --> 00:37:06,240
The Earth, during its early lifetime,
713
00:37:06,240 --> 00:37:08,850
experienced some very tumultuous years.
714
00:37:08,850 --> 00:37:10,950
So you can think of the Earth kind of
715
00:37:10,950 --> 00:37:13,293
as a teenager early on in its life.
716
00:37:14,250 --> 00:37:15,690
Not only the proximity
717
00:37:15,690 --> 00:37:18,720
to the Moon was causing havoc at this time,
718
00:37:18,720 --> 00:37:22,770
Earth itself was also spinning up to six times faster
719
00:37:22,770 --> 00:37:25,590
around its axis than it is today.
720
00:37:25,590 --> 00:37:27,990
It was a wild planet.
721
00:37:27,990 --> 00:37:29,520
Just after the Moon was formed,
722
00:37:29,520 --> 00:37:32,250
the Earth was spinning very, very fast.
723
00:37:32,250 --> 00:37:35,970
The length of the day was only about four hours.
724
00:37:35,970 --> 00:37:36,870
Earth was far
725
00:37:36,870 --> 00:37:39,720
from the hospitable world we have today,
726
00:37:39,720 --> 00:37:42,360
but this was about to change.
727
00:37:42,360 --> 00:37:45,900
The Moon, the very thing that was causing so much stress,
728
00:37:45,900 --> 00:37:50,190
was also about to help Earth take a vital step towards life.
729
00:37:50,190 --> 00:37:51,990
The Moon was tugging on the Earth
730
00:37:51,990 --> 00:37:54,780
so strongly it actually caused
731
00:37:54,780 --> 00:37:58,590
something called tidal friction, which caused energy
732
00:37:58,590 --> 00:38:01,533
to be lost from the early Earth-Moon system.
733
00:38:02,700 --> 00:38:03,630
Due to the fact
734
00:38:03,630 --> 00:38:05,850
that the Moon tugs at our planet,
735
00:38:05,850 --> 00:38:08,400
the tides were created.
736
00:38:08,400 --> 00:38:12,120
Huge waves bulge out and exert a gravitational pull
737
00:38:12,120 --> 00:38:14,340
on their own on the Moon.
738
00:38:14,340 --> 00:38:16,560
Because it takes time for all that water
739
00:38:16,560 --> 00:38:18,330
to shift and pile up,
740
00:38:18,330 --> 00:38:20,910
the bulging oceans don't exactly match up
741
00:38:20,910 --> 00:38:22,830
with the position of the Moon.
742
00:38:22,830 --> 00:38:25,470
They are always a little out of sync.
743
00:38:25,470 --> 00:38:29,910
This creates friction that slows Earth's own rotation,
744
00:38:29,910 --> 00:38:32,130
albeit very slowly.
745
00:38:32,130 --> 00:38:37,130
Every 50,000 years, the days become one second longer.
746
00:38:37,620 --> 00:38:39,600
This also creates forces
747
00:38:39,600 --> 00:38:42,150
that change the Moon's orbital speed,
748
00:38:42,150 --> 00:38:45,453
causing it to slowly fall away into space.
749
00:38:47,910 --> 00:38:51,030
Today, the Moon is still moving away from the Earth,
750
00:38:51,030 --> 00:38:54,330
little bit by little bit, about four centimeters per year.
751
00:38:54,330 --> 00:38:56,430
As the Moon moves away,
752
00:38:56,430 --> 00:38:58,590
the gravitational pull is a little bit less
753
00:38:58,590 --> 00:39:00,240
and that allows the Earth's rotation
754
00:39:00,240 --> 00:39:03,000
to slow down just a tiny bit.
755
00:39:03,000 --> 00:39:06,930
As this happens, the moon will slowly move away.
756
00:39:06,930 --> 00:39:09,453
The amount of friction decreases,
757
00:39:10,560 --> 00:39:14,340
leaving the Earth in a much more placid and calm place
758
00:39:14,340 --> 00:39:15,815
for the origin of life.
759
00:39:15,815 --> 00:39:16,950
(awe-inspiring music)
760
00:39:16,950 --> 00:39:18,237
As time passed
761
00:39:18,237 --> 00:39:20,700
and the Moon continued to move away,
762
00:39:20,700 --> 00:39:23,580
our days gradually got longer
763
00:39:23,580 --> 00:39:27,630
and Earth's rotation got slower and slower.
764
00:39:27,630 --> 00:39:31,860
The new Moon finally brought stability to our planet,
765
00:39:31,860 --> 00:39:35,433
setting the stage for life to begin.
766
00:39:39,660 --> 00:39:43,170
At the Ludwig Maximilian University in Munich, Germany,
767
00:39:43,170 --> 00:39:44,850
scientists want to find out
768
00:39:44,850 --> 00:39:47,733
how life might have evolved on early Earth.
769
00:39:48,870 --> 00:39:53,013
For Professor Oliver Trapp, chemistry is the key to life.
770
00:39:54,960 --> 00:39:57,090
You can create new molecules,
771
00:39:57,090 --> 00:40:00,150
you can create new functionality,
772
00:40:00,150 --> 00:40:03,270
and you can make absolute new matter,
773
00:40:03,270 --> 00:40:05,370
which didn't exist before.
774
00:40:05,370 --> 00:40:09,690
And this was already fascinating me as a child.
775
00:40:09,690 --> 00:40:10,830
In his laboratory,
776
00:40:10,830 --> 00:40:12,990
Professor Trapp wants to understand
777
00:40:12,990 --> 00:40:17,400
how life formed over 4.3 billion years ago.
778
00:40:17,400 --> 00:40:19,740
My goal of this research is
779
00:40:19,740 --> 00:40:24,740
that we discover a mechanism which led to evolution.
780
00:40:25,890 --> 00:40:29,103
Oliver Trapp wants to form life in a test tube.
781
00:40:30,210 --> 00:40:33,300
We try to simulate the processes
782
00:40:33,300 --> 00:40:35,970
which took place on the early Earth.
783
00:40:35,970 --> 00:40:37,470
Trapp's work is based
784
00:40:37,470 --> 00:40:39,810
on a groundbreaking experiment.
785
00:40:39,810 --> 00:40:43,530
In 1953, biologist and chemist, Stanley Miller,
786
00:40:43,530 --> 00:40:45,510
and his mentor, Harold Urey,
787
00:40:45,510 --> 00:40:48,660
built a setup that tries to show that life emerged
788
00:40:48,660 --> 00:40:50,880
from a primordial soup.
789
00:40:50,880 --> 00:40:54,155
They injected ammonia, methane, and water vapor
790
00:40:54,155 --> 00:40:57,930
into an enclosed glass container to simulate
791
00:40:57,930 --> 00:41:00,540
what were then believed to be the conditions
792
00:41:00,540 --> 00:41:03,000
of Earth's early atmosphere.
793
00:41:03,000 --> 00:41:08,000
Finally, Miller and Urey also replicated lightning strikes.
794
00:41:08,340 --> 00:41:13,140
They induced a reaction by making sparks,
795
00:41:13,140 --> 00:41:17,250
and the amazing outcome was that they observed the formation
796
00:41:17,250 --> 00:41:18,900
of amino acids.
797
00:41:18,900 --> 00:41:20,970
Amino acids are the molecules
798
00:41:20,970 --> 00:41:23,130
that combine to form proteins
799
00:41:23,130 --> 00:41:26,250
and are the building blocks of life on Earth.
800
00:41:26,250 --> 00:41:28,590
The experiment laid the foundation
801
00:41:28,590 --> 00:41:31,560
to further research on the origin of life,
802
00:41:31,560 --> 00:41:34,320
but Miller and Urey made one mistake.
803
00:41:34,320 --> 00:41:36,210
What they didn't know at this time
804
00:41:36,210 --> 00:41:38,460
was the composition of the atmosphere.
805
00:41:38,460 --> 00:41:43,460
They assumed that we had an atmosphere with methane gas,
806
00:41:43,740 --> 00:41:46,773
and it turned out in the 90s that this was wrong.
807
00:41:47,940 --> 00:41:49,410
Professor Trapp now wants
808
00:41:49,410 --> 00:41:51,210
to repeat this experiment,
809
00:41:51,210 --> 00:41:55,050
but this time he's incorporating the latest understanding
810
00:41:55,050 --> 00:41:58,440
of the composition of ancient planet Earth.
811
00:41:58,440 --> 00:42:01,920
The starting ingredients is the inorganic matter
812
00:42:01,920 --> 00:42:04,143
that was available on early Earth.
813
00:42:06,630 --> 00:42:07,950
So we are starting really
814
00:42:07,950 --> 00:42:09,960
from very, very simple molecules.
815
00:42:09,960 --> 00:42:13,740
We had carbon dioxide in the atmosphere.
816
00:42:13,740 --> 00:42:18,740
We had water also as vapor, as steam in the air,
817
00:42:19,170 --> 00:42:21,003
and, of course, nitrogen.
818
00:42:21,930 --> 00:42:24,120
But Oliver Trapp also adds
819
00:42:24,120 --> 00:42:26,580
a dissolved meteorite to the mix
820
00:42:26,580 --> 00:42:28,470
to duplicate the bombardments
821
00:42:28,470 --> 00:42:31,080
that took place on early Earth.
822
00:42:31,080 --> 00:42:35,670
By this, he creates simple organic molecules.
823
00:42:35,670 --> 00:42:39,300
Now, Professor Trapp puts this primordial soup
824
00:42:39,300 --> 00:42:41,850
into a container, together with water,
825
00:42:41,850 --> 00:42:44,760
which is heated to induce evaporation,
826
00:42:44,760 --> 00:42:46,710
replicating the water cycle
827
00:42:46,710 --> 00:42:50,100
as it may have been 4 billion years ago.
828
00:42:50,100 --> 00:42:54,480
Then comes the final important step of the experiment.
829
00:42:54,480 --> 00:42:55,920
This is a Tesla coil.
830
00:42:55,920 --> 00:43:00,600
It generates sparks and this simulates day and night cycles,
831
00:43:00,600 --> 00:43:03,420
which is very important to have the energy
832
00:43:03,420 --> 00:43:06,510
from the Sun in our reaction setup.
833
00:43:06,510 --> 00:43:11,215
And I expect that this will trigger new reactions
834
00:43:11,215 --> 00:43:13,983
and provide new material.
835
00:43:15,480 --> 00:43:18,330
1 million volts ionize the air
836
00:43:18,330 --> 00:43:19,743
and generate lightning.
837
00:43:21,120 --> 00:43:22,920
Each flash replicates a day
838
00:43:22,920 --> 00:43:26,583
on which the Sun supplies our young planet with energy.
839
00:43:27,750 --> 00:43:32,643
By doing so, Professor Trapp simulates years of evolution.
840
00:43:34,470 --> 00:43:36,600
This actually doesn't look like much.
841
00:43:36,600 --> 00:43:38,190
It looks like water.
842
00:43:38,190 --> 00:43:40,890
But if the experiment worked,
843
00:43:40,890 --> 00:43:43,740
we will have the first building blocks of life.
844
00:43:43,740 --> 00:43:45,960
The molecules are much too small
845
00:43:45,960 --> 00:43:47,940
for the eye to see.
846
00:43:47,940 --> 00:43:51,870
Using a gas chromatograph, Professor Trapp can find out
847
00:43:51,870 --> 00:43:55,110
what has formed in his primordial soup.
848
00:43:55,110 --> 00:43:58,620
This is adenosine, cytosine, and guanosine,
849
00:43:58,620 --> 00:44:01,710
and these are the DNA building blocks.
850
00:44:01,710 --> 00:44:04,080
So far, we have not formed life,
851
00:44:04,080 --> 00:44:08,070
but I'm pretty sure that with this we can continue,
852
00:44:08,070 --> 00:44:10,950
and we will see the formation of life
853
00:44:10,950 --> 00:44:14,703
in a test tube starting from inorganic material.
854
00:44:15,927 --> 00:44:17,400
It is these compounds
855
00:44:17,400 --> 00:44:19,980
which would eventually kickstart the evolution
856
00:44:19,980 --> 00:44:21,543
of life on Earth.
857
00:44:22,410 --> 00:44:24,270
Over millions of years,
858
00:44:24,270 --> 00:44:26,640
these building blocks would replicate
859
00:44:26,640 --> 00:44:29,100
and assemble into cell membranes
860
00:44:29,100 --> 00:44:33,003
until eventually a single-celled organism emerged.
861
00:44:34,080 --> 00:44:38,160
This organism, which lived around 4 billion years ago,
862
00:44:38,160 --> 00:44:40,770
would become known as LUCA,
863
00:44:40,770 --> 00:44:44,070
our last universal common ancestor.
864
00:44:44,070 --> 00:44:46,917
But where on Earth did life begin?
865
00:44:46,917 --> 00:44:50,310
(dramatic music)
866
00:44:50,310 --> 00:44:55,260
One possibility is the deep sea around hydrothermal vents.
867
00:44:55,260 --> 00:44:57,900
Chimneys formed where seawater comes
868
00:44:57,900 --> 00:45:01,140
into contact with magma on the ocean floor,
869
00:45:01,140 --> 00:45:05,100
resulting in streams of super-heated plumes.
870
00:45:05,100 --> 00:45:07,170
But life may as well have formed
871
00:45:07,170 --> 00:45:11,160
in scalding, highly acidic hot springs environments,
872
00:45:11,160 --> 00:45:14,763
like those found today in the Yellowstone National Park.
873
00:45:16,020 --> 00:45:18,750
Eventually, the organism's ancestors
874
00:45:18,750 --> 00:45:21,453
will make the first step outside of water.
875
00:45:22,380 --> 00:45:26,313
How and why this happened is only just being revealed,
876
00:45:27,360 --> 00:45:29,730
but what is clear already is
877
00:45:29,730 --> 00:45:34,380
that our hostile Earth plays the central role
878
00:45:34,380 --> 00:45:36,573
in the evolution of life.
879
00:45:41,790 --> 00:45:44,010
One of the best places to understand
880
00:45:44,010 --> 00:45:47,880
just how hostile our early planet was can be found
881
00:45:47,880 --> 00:45:50,430
right here on Earth today.
882
00:45:50,430 --> 00:45:53,943
The Atacama is one of the driest deserts in the world.
883
00:45:54,930 --> 00:45:57,630
Here, a team of German biologists try
884
00:45:57,630 --> 00:46:01,260
to trace the ways in which early life evolved.
885
00:46:01,260 --> 00:46:04,050
And they want to find out how life was able
886
00:46:04,050 --> 00:46:06,796
to gain a foothold outside of water.
887
00:46:06,796 --> 00:46:08,875
Hi, Michael.
Hi, Luis.
888
00:46:08,875 --> 00:46:10,407
Nice to meet you.
Nice to meet you.
889
00:46:10,407 --> 00:46:11,421
Hi, I'm Patrick.
890
00:46:11,421 --> 00:46:12,600
Nice to meet you.
Hi, Luis.
891
00:46:12,600 --> 00:46:14,700
Nice to meet you.
Hello.
892
00:46:14,700 --> 00:46:17,460
The Pan de Azucar National Park is part
893
00:46:17,460 --> 00:46:19,650
of the Atacama Desert.
894
00:46:19,650 --> 00:46:21,330
Within the park, there is supposed
895
00:46:21,330 --> 00:46:25,440
to be an area which is particularly hostile to life,
896
00:46:25,440 --> 00:46:27,963
a place that is closed to the public.
897
00:46:30,810 --> 00:46:34,080
The deeper Patrick Jung and Michael Lakatos venture
898
00:46:34,080 --> 00:46:35,250
into the desert,
899
00:46:35,250 --> 00:46:38,490
the more barren the landscape becomes.
900
00:46:38,490 --> 00:46:42,990
Here, it is so dry that seemingly nothing grows anymore.
901
00:46:42,990 --> 00:46:45,453
The perfect place to search for life.
902
00:46:46,500 --> 00:46:47,880
On the desert floor,
903
00:46:47,880 --> 00:46:51,603
a dark crust is the only unusual thing they discover.
904
00:46:55,140 --> 00:46:57,233
Can you imagine what that might be?
905
00:46:58,620 --> 00:47:00,240
It's mineral.
906
00:47:00,240 --> 00:47:01,830
Do you really think so?
907
00:47:01,830 --> 00:47:04,430
Yes. Those are black pebbles here.
908
00:47:05,310 --> 00:47:06,600
Closer analysis
909
00:47:06,600 --> 00:47:10,200
of the desert floor amazes the scientists.
910
00:47:10,200 --> 00:47:13,320
Tiny dark cracks run through the pebbles.
911
00:47:13,320 --> 00:47:14,460
For the experts,
912
00:47:14,460 --> 00:47:18,333
this is a possible sign of biological activity.
913
00:47:21,150 --> 00:47:21,983
I have another idea.
914
00:47:21,983 --> 00:47:23,260
You got that water bottle?
915
00:47:26,250 --> 00:47:27,360
The scientists know
916
00:47:27,360 --> 00:47:30,930
that this rock does not absorb water.
917
00:47:30,930 --> 00:47:33,960
If it does, this would be a clear sign
918
00:47:33,960 --> 00:47:36,453
that it has been penetrated by an organism.
919
00:47:39,990 --> 00:47:41,490
You see how it changes?
920
00:47:41,490 --> 00:47:42,960
Oh, yeah.
921
00:47:42,960 --> 00:47:44,783
Now let's give it a moment.
922
00:47:46,560 --> 00:47:48,030
I'm going to look through there again,
923
00:47:48,030 --> 00:47:50,223
but I think I can see it turning green.
924
00:47:52,740 --> 00:47:54,090
A change in color
925
00:47:54,090 --> 00:47:56,100
would also indicate the presence
926
00:47:56,100 --> 00:47:57,993
of an organism in the stone.
927
00:47:59,340 --> 00:48:00,270
We just found out
928
00:48:00,270 --> 00:48:01,950
that these are microorganisms
929
00:48:01,950 --> 00:48:04,290
that are sitting on these little pebbles,
930
00:48:04,290 --> 00:48:06,120
and now we have to take our instruments
931
00:48:06,120 --> 00:48:08,220
to find out what they are doing here,
932
00:48:08,220 --> 00:48:09,480
how they can survive,
933
00:48:09,480 --> 00:48:11,793
and what kind of microorganisms they are.
934
00:48:15,390 --> 00:48:16,440
The scientists want
935
00:48:16,440 --> 00:48:21,150
to find out whether these microorganisms are actually alive.
936
00:48:21,150 --> 00:48:24,060
For this, they are using a measuring device
937
00:48:24,060 --> 00:48:27,633
that is capable of detecting photosynthetic activity.
938
00:48:28,590 --> 00:48:31,530
First, they measure the dry rock.
939
00:48:31,530 --> 00:48:35,193
The red color of the display means no activity.
940
00:48:38,010 --> 00:48:39,030
So hold on.
941
00:48:39,030 --> 00:48:40,503
I sprinkle it with water now.
942
00:48:44,580 --> 00:48:46,080
You can start the measurement.
943
00:48:49,410 --> 00:48:50,880
That's amazing.
944
00:48:50,880 --> 00:48:53,040
It's alive.
945
00:48:53,040 --> 00:48:55,110
We found out that there's a color change
946
00:48:55,110 --> 00:48:56,880
of the photosynthetic signal.
947
00:48:56,880 --> 00:48:59,520
That is, it flips from red to green and blue,
948
00:48:59,520 --> 00:49:03,060
and that shows us we actually have photosynthetic activity
949
00:49:03,060 --> 00:49:04,563
here, and therefore life.
950
00:49:07,290 --> 00:49:09,000
With a field microscope,
951
00:49:09,000 --> 00:49:10,290
the scientists now want
952
00:49:10,290 --> 00:49:13,320
to find out which organisms have been able
953
00:49:13,320 --> 00:49:16,383
to survive in this hostile environment.
954
00:49:19,740 --> 00:49:20,573
Michael, come here
955
00:49:20,573 --> 00:49:23,430
and take a look at this.
956
00:49:23,430 --> 00:49:26,823
When I adjust the focus, you can see that there is a lichen.
957
00:49:28,590 --> 00:49:31,110
So you can see the fungal structures,
958
00:49:31,110 --> 00:49:33,240
and here the green algae.
959
00:49:33,240 --> 00:49:35,133
And also here. It's everywhere.
960
00:49:36,600 --> 00:49:38,663
That's really beautiful.
961
00:49:39,690 --> 00:49:42,480
Lichens are symbiotic microorganisms
962
00:49:42,480 --> 00:49:46,290
that exist on Earth for about 400 million years.
963
00:49:46,290 --> 00:49:49,653
In this case, they consist of an algae and a fungus.
964
00:49:50,880 --> 00:49:53,790
The algae is photosynthetically active,
965
00:49:53,790 --> 00:49:56,730
so it converts light, CO2 from the air,
966
00:49:56,730 --> 00:49:58,710
and water into sugars,
967
00:49:58,710 --> 00:50:02,040
and these sugars can be taken up by the fungus partner.
968
00:50:02,040 --> 00:50:02,913
It feeds on them.
969
00:50:03,750 --> 00:50:07,020
And in return, the fungus partner positions the algae
970
00:50:07,020 --> 00:50:09,060
in the lichen in an optimal position
971
00:50:09,060 --> 00:50:10,980
in the organism that is formed
972
00:50:10,980 --> 00:50:14,760
so that the algae can optimally photosynthesize.
973
00:50:14,760 --> 00:50:16,590
Only through this symbiosis can
974
00:50:16,590 --> 00:50:19,520
these individual partners survive here together
975
00:50:19,520 --> 00:50:21,063
in the Atacama Desert.
976
00:50:23,820 --> 00:50:25,830
But from where does the organism
977
00:50:25,830 --> 00:50:28,263
in this area get the vital water?
978
00:50:30,180 --> 00:50:31,710
We are in one of the driest
979
00:50:31,710 --> 00:50:33,600
and oldest deserts on earth,
980
00:50:33,600 --> 00:50:36,120
but still we are only about 12 kilometers
981
00:50:36,120 --> 00:50:38,580
from the coast that is over here.
982
00:50:38,580 --> 00:50:41,940
Water vapor rises there, condenses out as fog,
983
00:50:41,940 --> 00:50:44,940
and then moves very flat across the landscape.
984
00:50:44,940 --> 00:50:47,280
That's a super small amount of water input,
985
00:50:47,280 --> 00:50:50,163
but that amount is enough to make life possible here.
986
00:50:52,830 --> 00:50:53,760
With a drone,
987
00:50:53,760 --> 00:50:56,070
the scientists now want to get an overview
988
00:50:56,070 --> 00:50:58,473
of the distribution of these organisms.
989
00:51:00,990 --> 00:51:03,480
Yeah. Go up a little bit more.
990
00:51:03,480 --> 00:51:04,800
Right.
991
00:51:04,800 --> 00:51:07,500
Now if you go to the left another bit.
992
00:51:07,500 --> 00:51:09,510
Gradually, the full extent
993
00:51:09,510 --> 00:51:11,583
of the growth is revealed.
994
00:51:12,660 --> 00:51:15,410
Look at this. It's really everywhere.
995
00:51:17,790 --> 00:51:20,700
Patrick Jung and Michael Lakatos suspect
996
00:51:20,700 --> 00:51:23,790
that the lichens here form a superorganism,
997
00:51:23,790 --> 00:51:27,120
comparable to a coral reef that covers large parts
998
00:51:27,120 --> 00:51:29,433
of the hostile Atacama Desert.
999
00:51:31,560 --> 00:51:33,450
The microorganisms that we found here
1000
00:51:33,450 --> 00:51:35,940
are adapted to extreme locations.
1001
00:51:35,940 --> 00:51:36,960
By working together,
1002
00:51:36,960 --> 00:51:39,780
they have made this leap into the landscape,
1003
00:51:39,780 --> 00:51:41,910
and that's a comparable situation
1004
00:51:41,910 --> 00:51:44,583
to what we find in the early history of the Earth.
1005
00:51:45,480 --> 00:51:47,343
Through these abilities out of the cooperation
1006
00:51:47,343 --> 00:51:50,490
and symbiosis of adapted microorganisms,
1007
00:51:50,490 --> 00:51:54,033
life that originated in water might have leaped on land.
1008
00:51:56,160 --> 00:51:59,100
After almost 4 billion years,
1009
00:51:59,100 --> 00:52:04,050
life has developed innumerable characteristics and forms.
1010
00:52:04,050 --> 00:52:05,820
In the course of evolution,
1011
00:52:05,820 --> 00:52:09,870
highly complex living beings have developed.
1012
00:52:09,870 --> 00:52:13,770
But the road to the diversity we have today is a long
1013
00:52:13,770 --> 00:52:18,770
and rocky one that puts life to the test again and again.
1014
00:52:21,270 --> 00:52:24,030
However, one thing is for sure.
1015
00:52:24,030 --> 00:52:25,410
Without catastrophes,
1016
00:52:25,410 --> 00:52:28,320
like the apocalyptic collision with Theia,
1017
00:52:28,320 --> 00:52:31,980
life on Earth as we know it today
1018
00:52:31,980 --> 00:52:33,231
would not exist.
1019
00:52:33,231 --> 00:52:36,398
(awe-inspiring music)
1020
00:52:39,985 --> 00:52:42,735
(dramatic music)
1021
00:53:09,081 --> 00:53:12,664
(dramatic music continues)