1
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sᴜᴘᴘᴏʀᴛ ʙʏ
2
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sᴜᴘᴘᴏʀᴛ ʙʏ
Protocol Labs
3
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sᴜᴘᴘᴏʀᴛ ʙʏ
Protocol Labs
Follow your curiosity.
4
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sᴜᴘᴘᴏʀᴛ ʙʏ
Protocol Labs
Follow your curiosity.
Lead humanity forward.
5
00:00:09,187 --> 00:00:09,437
Protocol Labs
Follow your curiosity.
Lead humanity forward.
6
00:00:09,437 --> 00:00:09,687
Follow your curiosity.
Lead humanity forward.
7
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"In all the universe,
8
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"In all the universe,
there stands only one known tree of life."
9
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"Does it stand alone?
10
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"Does it stand alone?
Or is it part of a vast cosmic wilderness?"
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"Imagine a museum
containing every type of life in the universe."
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"What strange things would such a museum hold?"
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"What is possible under the laws of nature?"
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LIFE
15
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LIFE BEYOND
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CHAPTER II
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CHAPTER II
The Museum Of Alien Life
18
00:02:02,805 --> 00:02:03,657
To have any hope-
19
00:02:03,657 --> 00:02:05,506
of finding alien life,
20
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we have to know what to look for.
21
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But where do we begin?
22
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How do we narrow down...
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00:02:16,568 --> 00:02:18,068
a seemingly infinite set-
24
00:02:18,068 --> 00:02:20,175
of possibilities...
25
00:02:27,310 --> 00:02:29,968
There's one thing we know for sure...
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nature will have to play-
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by her own rules.
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No matter how strange-
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alien life might be,
30
00:02:40,386 --> 00:02:41,180
is going to be limited-
31
00:02:41,220 --> 00:02:42,596
by the same physical...
32
00:02:42,606 --> 00:02:44,756
and chemical laws that we are....
33
00:02:46,952 --> 00:02:47,014
6
34
00:02:47,014 --> 00:02:47,077
6 C
35
00:02:47,077 --> 00:02:47,139
6 CO
36
00:02:47,139 --> 00:02:47,202
6 CO₂
37
00:02:47,202 --> 00:02:47,264
6 CO₂ +
38
00:02:47,264 --> 00:02:47,327
6 CO₂ + 6
39
00:02:47,327 --> 00:02:47,389
6 CO₂ + 6 H
40
00:02:47,389 --> 00:02:47,452
6 CO₂ + 6 H₂
41
00:02:47,452 --> 00:02:47,514
6 CO₂ + 6 H₂O
42
00:02:47,514 --> 00:02:47,577
6 CO₂ + 6 H₂O +
43
00:02:47,577 --> 00:02:47,639
6 CO₂ + 6 H₂O + L
44
00:02:47,639 --> 00:02:47,702
6 CO₂ + 6 H₂O + Li
45
00:02:47,702 --> 00:02:47,764
6 CO₂ + 6 H₂O + Lig
46
00:02:47,764 --> 00:02:47,827
6 CO₂ + 6 H₂O + Ligh
47
00:02:47,827 --> 00:02:47,889
6 CO₂ + 6 H₂O + Light
48
00:02:47,889 --> 00:02:47,952
6 CO₂ + 6 H₂O + Light →
49
00:02:47,952 --> 00:02:48,014
6 CO₂ + 6 H₂O + Light → C
50
00:02:48,014 --> 00:02:48,077
6 CO₂ + 6 H₂O + Light → C₆
51
00:02:48,077 --> 00:02:48,139
6 CO₂ + 6 H₂O + Light → C₆H
52
00:02:48,139 --> 00:02:48,202
6 CO₂ + 6 H₂O + Light → C₆H₁
53
00:02:48,202 --> 00:02:48,264
6 CO₂ + 6 H₂O + Light → C₆H₁₂
54
00:02:48,264 --> 00:02:48,326
6 CO₂ + 6 H₂O + Light → C₆H₁₂O
55
00:02:48,326 --> 00:02:48,389
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆
56
00:02:48,389 --> 00:02:48,451
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆ +
57
00:02:48,451 --> 00:02:48,514
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆ + 6
58
00:02:48,514 --> 00:02:48,576
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆ + 6 O
59
00:02:48,576 --> 00:02:51,613
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆ + 6 O₂
60
00:02:51,613 --> 00:02:52,312
On top of this,
6 CO₂ + 6 H₂O + Light → C₆H₁₂O₆ + 6 O₂
61
00:02:52,312 --> 00:02:52,733
On top of this,
62
00:02:53,244 --> 00:02:53,694
each alien environment will further limit-
63
00:02:53,694 --> 00:02:55,239
each alien environment will further limit-
ʜʏᴅʀᴏɢᴇɴ
64
00:02:55,239 --> 00:02:55,672
each alien environment will further limit-
ᴏxʏɢᴇɴ
65
00:02:55,672 --> 00:02:57,374
what kinds of life forms can evolve there.
ᴏxʏɢᴇɴ
66
00:02:57,374 --> 00:02:59,376
what kinds of life forms can evolve there.
ɴɪᴛʀᴏɢᴇɴ
67
00:03:06,992 --> 00:03:09,189
Despite these natural boundaries,
68
00:03:09,243 --> 00:03:12,206
the possibilities are staggering to imagine.
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00:03:14,235 --> 00:03:15,640
Trillions of planets,
70
00:03:15,778 --> 00:03:17,878
each a unique cauldron of chemicals,
71
00:03:17,924 --> 00:03:23,076
undergoing their own complex evolution.
72
00:03:28,150 --> 00:03:29,360
To guide our thinking,
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this museum of alien life-
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will be divided into two exhibits...
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Life as we know it,
76
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home to beings-
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with bio-chemistries like ours.
78
00:03:41,694 --> 00:03:43,588
And life as we don't know it,
79
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home to beings-
80
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that challenge our concept of life itself.
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Before we venture-
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too far into the unknown,
83
00:03:57,103 --> 00:03:59,177
we have to ask ourselves...
84
00:03:59,956 --> 00:04:01,089
what if alien life-
85
00:04:01,183 --> 00:04:02,253
is more like us...
86
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than we think?
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EXHIBIT I
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EXHIBIT I
Life As We Know It
89
00:04:14,746 --> 00:04:15,174
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
90
00:04:15,174 --> 00:04:16,307
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
If there's one feature-
91
00:04:16,307 --> 00:04:17,327
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
that unites us...
92
00:04:17,327 --> 00:04:19,510
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
with these other specimes in this museum,
93
00:04:19,510 --> 00:04:19,922
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
94
00:04:19,922 --> 00:04:21,245
EXHIBIT I
Life As We Know It
ᶜᵃʳᵇᵒⁿ ᵃⁿᵈ ʷᵃᵗᵉʳ ᵇᵃˢᵉᵈ
it's carbon...
95
00:04:21,775 --> 00:04:24,670
Carbon
96
00:04:24,670 --> 00:04:26,377
Carbon
Carbon is ubiquitous,
97
00:04:26,437 --> 00:04:27,514
Carbon
it's one o' tho most-
98
00:04:27,514 --> 00:04:29,450
Carbon
common elements in the universe,
99
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Carbon
and is very good at forming-
100
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Carbon
large stable molecules.
101
00:04:33,505 --> 00:04:37,183
Carbon
102
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Carbon
Carbon has the rare ability to form four way
bounds with other elements
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00:04:41,563 --> 00:04:41,807
Carbon
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Carbon
and to bind to itself in
long, stable chains;
105
00:04:46,424 --> 00:04:49,624
enabling the formation of
huge complex molecules.
106
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This versatility makes carbon the center piece
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in the moleculary machinery of life.
108
00:05:03,520 --> 00:05:07,742
And the same carbon compounds that we use
have been found far from Earth,
109
00:05:08,736 --> 00:05:10,087
clinging to meteorites
110
00:05:12,359 --> 00:05:15,623
and floating in far off
clouds of cosmic dust.
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00:05:18,670 --> 00:05:23,518
The building blocks of life drifting
like snow through the universe.
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00:05:30,162 --> 00:05:34,920
And if alien life has selected other carbon
compounds for the biochemistry,
113
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they will have plenty to choose from.
114
00:05:42,088 --> 00:05:47,570
Scientists recently identified over a
million possible alternatives to DNA:
115
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all carbon based.
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If we ever discover other
carbon based life forms,
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we will be fundamentally related.
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They will be our cosmic brother.
119
00:06:13,296 --> 00:06:15,137
But would they look anything like us?
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If they hail from Earth like planets,
121
00:06:22,857 --> 00:06:24,471
we could share even more in common,
122
00:06:25,065 --> 00:06:26,417
than just our biochemistry.
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What would life be like in another
planets, if its evolved?
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Would it be like, the world
today here on Earth?
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Or would be completely different?
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00:06:38,819 --> 00:06:42,121
There are those, who argue that
127
00:06:42,456 --> 00:06:44,470
from the argument of convergent evolution,
128
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if conditions on other planets are similar to here, then we will see very similar life forms;
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00:06:54,726 --> 00:06:58,236
animal and plant-like organisms, that look very familiar.
130
00:07:12,238 --> 00:07:16,618
On Earth, certain features like eyesight, echo-location and flight
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00:07:16,628 --> 00:07:20,812
have evolved multiple times, independently, in different species.
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This process of convergent evolution could extend to alien planets like Earth,
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where creatures share similar environmental pressures.
134
00:07:35,632 --> 00:07:40,372
It's no guarantee, but there could be certain universalities of life;
135
00:07:44,337 --> 00:07:48,337
the greatest hits of evolution on repeat across the Universe.
136
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Each feature would be a tune to its local environment.
137
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Dimly lit planets would produce huge eyes to suck in extra light, like nocturnal mammals.
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Some people have gone so far as to say
that human type organism, humanoids,
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will occur on other planets.
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00:08:26,136 --> 00:08:29,706
The existence of other human-like
organisms seems unlikely,
141
00:08:30,155 --> 00:08:33,602
given the long convoluted chain
of events that produced us.
142
00:08:35,296 --> 00:08:36,400
But we can't rule it out.
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00:08:40,817 --> 00:08:44,838
If just one in every 100 trillion
Earth-like planets produced
144
00:08:44,838 --> 00:08:49,551
a human-like form, the could still be
thousands of creatures like us out there.
145
00:09:02,605 --> 00:09:07,335
But in reality, we are more likely to find
something lower on the food chain.
146
00:09:10,171 --> 00:09:13,423
Convergent evolution is also
rampant in plant life
147
00:09:14,037 --> 00:09:19,312
and C4 photosynthesis has arisen
independently over 40 times.
148
00:09:21,799 --> 00:09:25,178
Would alien plants look like ours or
something else entirely?
149
00:09:36,926 --> 00:09:40,857
On Earth, plants appear green because
they absorb the other wavelenghts
150
00:09:40,997 --> 00:09:42,537
in the Sun's light spectrum.
151
00:09:45,739 --> 00:09:47,778
But stars come in many colors
152
00:09:52,629 --> 00:09:56,984
and alien plants would evolve different pigments
to adapt to their sun's unique spectrum.
153
00:10:04,431 --> 00:10:07,530
Plants feeding off hotter stars
could appear redder,
154
00:10:08,284 --> 00:10:11,161
by absorbing their energy rich bluer light.
155
00:10:19,761 --> 00:10:24,219
Around dim Red Dwarfs stars,
vegetation could appear black,
156
00:10:25,072 --> 00:10:28,155
adapted to absorb all visible
wavelengths of light.
157
00:10:45,058 --> 00:10:47,572
Earth itself may have once
appeared purple,
158
00:10:48,101 --> 00:10:52,004
due a pigment called retinal, that was
an early precursor to chlorophyll.
159
00:10:55,019 --> 00:10:57,779
Some think that retinal's molecular simplicity
160
00:10:58,189 --> 00:11:00,547
could make it a more universal pigment.
161
00:11:04,070 --> 00:11:09,146
If so, we may find that purple,
is life's favorite color.
162
00:11:19,820 --> 00:11:23,713
But the color of alien vegetation
is more than just a curiosity,
163
00:11:25,696 --> 00:11:29,155
it's chemical information that could
be seen from light years away.
164
00:11:34,504 --> 00:11:38,528
Earth plants leave a signature bump
in the light reflected off our planet.
165
00:11:40,306 --> 00:11:43,434
Finding a similar signal from another
world could point the way
166
00:11:43,647 --> 00:11:44,953
to alien vegetation.
167
00:11:50,376 --> 00:11:53,866
Perhaps this will be our first glimpse at alien life;
168
00:11:54,965 --> 00:11:58,375
a vibrant hue, cast by a distinct world.
169
00:12:12,005 --> 00:12:20,055
But the biggest influence on life won't be it's host star; it will be it's home planet.
170
00:12:20,715 --> 00:12:23,415
What happens, when you change the day - length of a planet?
171
00:12:23,495 --> 00:12:25,465
What happens when you change the tilt of a planet?
172
00:12:25,545 --> 00:12:27,626
What happens when you change the shape of the orbit?
173
00:12:27,965 --> 00:12:30,637
What happens when you change the gravity of a planet?
174
00:12:34,498 --> 00:12:38,938
Planets with long, elliptical orbits would see drastic seasons.
175
00:12:41,298 --> 00:12:44,823
There could be worlds that appear dead for thousands of years,
176
00:12:45,528 --> 00:12:47,496
then suddenly spring to life.
177
00:13:02,583 --> 00:13:07,073
Most of the rocky planets discovered so far have been massive "Super Earths".
178
00:13:09,243 --> 00:13:12,433
GJ 357 DSuper Earth Distance : ~ 31 Light Years Mass : ~ 7× Earth Temperature : ~ -53°C
179
00:13:12,570 --> 00:13:15,097
How would life evolve on these worlds?
180
00:13:18,580 --> 00:13:21,656
In the seas, gravity may not matter much at all.
181
00:13:29,590 --> 00:13:32,120
A high - gravity planet isn't high - gravity all over.
182
00:13:33,680 --> 00:13:37,660
If you're in the sea, that's where all life starts, there's very nearly no gravity,
183
00:13:37,660 --> 00:13:40,225
cause you're much the density as the stuff around you.
184
00:13:43,450 --> 00:13:47,270
It's when the animals come out on land, that they feel the gravity.
185
00:13:51,628 --> 00:13:53,628
High G - forces [vaguely, gravitational forces] would necessitate
186
00:13:53,628 --> 00:13:57,458
large bones and muscle mass in complex life on land.
187
00:13:59,748 --> 00:14:03,178
They would also demand a more robust circulatory system.
188
00:14:04,958 --> 00:14:10,578
And plant life could be stunted by the energy cost of carrying nutrients under stronger gravity.
189
00:14:17,318 --> 00:14:21,446
Low - gravity planets would more easily lose their atmospheres to space;
190
00:14:21,838 --> 00:14:25,158
and lack a magnetic field to protect from cosmic rays.
191
00:14:35,821 --> 00:14:39,091
But smaller worlds could be home to secret oases;
192
00:14:46,251 --> 00:14:49,451
huge cave systems that provide hide-outs for life.
193
00:15:02,751 --> 00:15:11,242
With steadier temperatures and protection from cosmic rays, life could thrive underground on planets with deadly surfaces.
194
00:15:26,732 --> 00:15:33,093
The smallest possible habitable planets are estimated at 2.5% Earth's mass.
195
00:15:35,042 --> 00:15:37,735
If surface life does evolve on these worlds,
196
00:15:38,822 --> 00:15:40,766
it could be a sight to behold.
197
00:15:44,584 --> 00:15:47,064
Plant life could grow to towering heights,
198
00:15:47,484 --> 00:15:50,594
able to carry nutrients higher, at lesser gravity.
199
00:15:59,194 --> 00:16:02,611
And without the need for bulky skeletons and muscle mass,
200
00:16:02,904 --> 00:16:06,031
animals could have body types, that boggle the mud.