1
00:00:00,435 --> 00:00:01,450
(dramatic music)

2
00:00:01,450 --> 00:00:03,420
2019 was a year filled

3
00:00:03,420 --> 00:00:06,997
with astonishing discoveries on Earth and beyond.

4
00:00:06,997 --> 00:00:08,370
(suspenseful music)

5
00:00:08,370 --> 00:00:10,653
We inched closer to immortality.

6
00:00:12,240 --> 00:00:14,613
Recovered and restored our heritage.

7
00:00:16,370 --> 00:00:18,920
And science fiction became science fact

8
00:00:19,783 --> 00:00:22,971
when we saw the unseeable for the very first time.

9
00:00:22,971 --> 00:00:25,721
(dramatic music)

10
00:00:29,512 --> 00:00:32,512
(suspenseful music)

11
00:00:36,090 --> 00:00:38,370
It's hard to imagine anything more terrifying

12
00:00:38,370 --> 00:00:40,170
than a galactic vacuum cleaner

13
00:00:40,170 --> 00:00:43,363
that devours planets and even stars.

14
00:00:45,260 --> 00:00:47,760
Einstein predicted the existence of black holes

15
00:00:47,760 --> 00:00:52,243
in 1916 and researchers confirmed them in 1971.

16
00:00:54,320 --> 00:00:56,300
But, though plenty of indirect evidence

17
00:00:56,300 --> 00:00:58,860
was collected over the last half century,

18
00:00:58,860 --> 00:01:01,183
black holes are extremely camera shy.

19
00:01:02,070 --> 00:01:06,230
Scientists hadn't actually seen one until this year

20
00:01:06,230 --> 00:01:08,830
thanks to an unprecedented global effort

21
00:01:08,830 --> 00:01:11,163
and the Event Horizon Telescope.

22
00:01:12,480 --> 00:01:16,450
The EHT is made of radio telescopes working in concert

23
00:01:16,450 --> 00:01:18,023
all over the Earth.

24
00:01:18,950 --> 00:01:22,920
This is possible because of one powerful feature.

25
00:01:22,920 --> 00:01:25,990
Interferometry doesn't care how far the antenna dishes

26
00:01:25,990 --> 00:01:29,633
are separated as long as they're precisely synchronized.

27
00:01:31,360 --> 00:01:33,480
The combined antenna work as though

28
00:01:33,480 --> 00:01:36,470
they're a single telescope with a collecting surface

29
00:01:36,470 --> 00:01:38,403
as big as the distance between them.

30
00:01:40,470 --> 00:01:45,470
With antenna located in Hawaii, North and South America,

31
00:01:45,630 --> 00:01:49,600
Greenland, Europe, and the South Pole,

32
00:01:49,600 --> 00:01:51,960
the EHT has a collecting surface

33
00:01:51,960 --> 00:01:54,193
literally the size of the Earth.

34
00:01:56,200 --> 00:01:58,920
The project began three years ago when a team

35
00:01:58,920 --> 00:02:01,050
connected millions of gigabytes of data

36
00:02:01,050 --> 00:02:04,303
from a remote galaxy known as M87.

37
00:02:06,200 --> 00:02:08,690
The data sent from the vast network of telescopes

38
00:02:08,690 --> 00:02:12,030
was often spotty and random, so they figured out

39
00:02:12,030 --> 00:02:15,363
how to fill in the gaps by applying several algorithms.

40
00:02:16,640 --> 00:02:17,810
The result?

41
00:02:17,810 --> 00:02:19,940
A complete and groundbreaking image

42
00:02:19,940 --> 00:02:23,000
of a lopsided ring-like structure,

43
00:02:23,000 --> 00:02:26,023
a black hole in the center of the distant galaxy.

44
00:02:28,130 --> 00:02:30,730
Now, history is being made.

45
00:02:30,730 --> 00:02:33,383
A direct photograph has just been released.

46
00:02:34,600 --> 00:02:38,380
And we are delighted to be able to report to you today

47
00:02:38,380 --> 00:02:41,143
that we have seen what we thought was unseeable.

48
00:02:42,110 --> 00:02:46,427
We have seen and taken a picture of a black hole.

49
00:02:46,427 --> 00:02:48,660
(audience applauds)

50
00:02:48,660 --> 00:02:49,718
Here it is.

51
00:02:49,718 --> 00:02:52,718
(audience applauds)

52
00:02:53,767 --> 00:02:55,205
(soft ominous music)

53
00:02:55,205 --> 00:02:57,500
And this is the strongest evidence that we have to date

54
00:02:57,500 --> 00:02:59,480
for the existence of black holes.

55
00:02:59,480 --> 00:03:02,420
And it is also consistent, the shape of this shadow,

56
00:03:02,420 --> 00:03:04,160
to the precision of our measurements

57
00:03:04,160 --> 00:03:06,078
with Einstein's prediction.

58
00:03:06,078 --> 00:03:09,078
(audience applauds)

59
00:03:10,850 --> 00:03:12,430
Black holes come in sizes

60
00:03:12,430 --> 00:03:16,090
ranging from nanoscale to thousands of times larger

61
00:03:16,090 --> 00:03:17,903
than our entire solar system.

62
00:03:18,880 --> 00:03:23,363
The diameter of M87 is roughly 24 billion miles across.

63
00:03:25,160 --> 00:03:27,490
It's an object where the physical realm

64
00:03:27,490 --> 00:03:31,580
and the laws of physics as we know them have broken down.

65
00:03:31,580 --> 00:03:33,300
(ominous music)

66
00:03:33,300 --> 00:03:36,550
And yet, it retains the gravity of all the mass

67
00:03:36,550 --> 00:03:39,203
of every object it has ever devoured.

68
00:03:41,980 --> 00:03:44,130
So, this is an easy way to visualize

69
00:03:44,130 --> 00:03:46,710
how a black hole shadow is formed.

70
00:03:46,710 --> 00:03:49,460
We can start by looking at what happens to light

71
00:03:49,460 --> 00:03:51,650
when we have just flat space.

72
00:03:51,650 --> 00:03:53,230
And, as our normal experience is,

73
00:03:53,230 --> 00:03:55,920
light just follows straight paths.

74
00:03:55,920 --> 00:03:57,370
But if I put the black hole in the middle,

75
00:03:57,370 --> 00:03:59,520
the black hole will warp the spacetime

76
00:03:59,520 --> 00:04:01,420
all the way to the singularity.

77
00:04:01,420 --> 00:04:03,743
It takes light rays and bends them,

78
00:04:04,784 --> 00:04:06,460
and some of them actually go straight down

79
00:04:06,460 --> 00:04:08,460
the neck of the singularity.

80
00:04:08,460 --> 00:04:10,860
A shadow is what a black hole casts

81
00:04:10,860 --> 00:04:12,810
on its surrounding emission.

82
00:04:12,810 --> 00:04:16,460
So, as gas gets close to the black hole,

83
00:04:16,460 --> 00:04:18,623
it heats up, it emits light.

84
00:04:19,620 --> 00:04:22,540
The black hole spacetime with the presence

85
00:04:22,540 --> 00:04:24,520
of the horizon and with the presence

86
00:04:24,520 --> 00:04:28,030
of a density depression at the center,

87
00:04:28,030 --> 00:04:29,480
absorbs all the light there,

88
00:04:29,480 --> 00:04:33,610
so it leaves a central darkness which we call the shadow

89
00:04:33,610 --> 00:04:36,552
that the black hole imprints on the image.

90
00:04:36,552 --> 00:04:37,385
(dramatic music)

91
00:04:37,385 --> 00:04:38,700
And the Earth Horizon Telescope

92
00:04:38,700 --> 00:04:40,490
is just getting started.

93
00:04:40,490 --> 00:04:43,310
Data gathered from the various Earth-based locations

94
00:04:43,310 --> 00:04:46,540
is now being processed to reveal a new image

95
00:04:46,540 --> 00:04:49,220
of an altogether different black hole

96
00:04:49,220 --> 00:04:52,020
and will be released to the public in the coming months.

97
00:04:55,059 --> 00:04:55,892
(suspenseful music)

98
00:04:55,892 --> 00:04:57,270
As scientists continue to probe

99
00:04:57,270 --> 00:04:59,680
these mysterious cosmic monsters,

100
00:04:59,680 --> 00:05:01,800
they'll be able to puncture even more myths

101
00:05:01,800 --> 00:05:03,633
about how our universe was born.

102
00:05:07,852 --> 00:05:09,470
(controller chattering)

103
00:05:09,470 --> 00:05:12,280
And liftoff of the Cassini spacecraft

104
00:05:12,280 --> 00:05:14,830
on a billion-mile trek to Saturn.

105
00:05:14,830 --> 00:05:17,050
Each of the planets in our own solar system

106
00:05:17,050 --> 00:05:20,270
has a unique appearance and personality,

107
00:05:20,270 --> 00:05:23,713
especially Saturn with its iconic rings,

108
00:05:25,220 --> 00:05:28,170
rings of ice and rock that extend

109
00:05:28,170 --> 00:05:31,550
up to 175,000 miles outward,

110
00:05:31,550 --> 00:05:34,033
yet only average 30 feet in height.

111
00:05:36,238 --> 00:05:38,030
(suspenseful music)

112
00:05:38,030 --> 00:05:41,040
NASA's Cassini space probe spent 13 years

113
00:05:41,040 --> 00:05:43,890
studying Saturn and its rings before plunging

114
00:05:43,890 --> 00:05:47,640
to its death in 2017, but it left behind a wealth

115
00:05:47,640 --> 00:05:49,653
of data for researchers back home.

116
00:05:51,930 --> 00:05:54,520
Early this year, new information revealed

117
00:05:54,520 --> 00:05:56,720
that perhaps Saturn's rings formed only

118
00:05:56,720 --> 00:06:00,480
between 10 million and 100 million years ago,

119
00:06:00,480 --> 00:06:02,850
at a time when dinosaurs roamed Earth,

120
00:06:02,850 --> 00:06:05,303
and not during the birth of our solar system.

121
00:06:06,360 --> 00:06:08,940
The majestic gas giant may have once existed

122
00:06:08,940 --> 00:06:10,743
without its distinctive halo.

123
00:06:16,360 --> 00:06:19,380
We used to think of rings as these individual particles

124
00:06:19,380 --> 00:06:22,070
kind of bumping into each other and sort of floating

125
00:06:22,070 --> 00:06:25,600
around in space, and we now know that the bulk

126
00:06:25,600 --> 00:06:27,220
of Saturn's main rings,

127
00:06:27,220 --> 00:06:29,300
the particles actually stick together

128
00:06:29,300 --> 00:06:33,210
and they form these long strands that we call wakes,

129
00:06:33,210 --> 00:06:34,920
and that these wakes line up

130
00:06:34,920 --> 00:06:37,387
like the rows of a marching band.

131
00:06:37,387 --> 00:06:39,930
(suspenseful music)

132
00:06:39,930 --> 00:06:41,570
They have grooves, if you like,

133
00:06:41,570 --> 00:06:43,820
like an old-fashioned record,

134
00:06:43,820 --> 00:06:46,560
created as wakes of moons which are orbiting.

135
00:06:46,560 --> 00:06:48,960
Some of the moons are in the rings,

136
00:06:48,960 --> 00:06:51,340
some of those moons are outside the rings,

137
00:06:51,340 --> 00:06:54,223
and these waves give an interesting texture.

138
00:06:57,520 --> 00:06:59,760
They break apart and they reform,

139
00:06:59,760 --> 00:07:02,400
so there's this beautiful cosmic dance

140
00:07:02,400 --> 00:07:04,053
going on inside the rings.

141
00:07:04,950 --> 00:07:06,430
And Cassini wasn't the only one

142
00:07:06,430 --> 00:07:07,980
getting in on the action.

143
00:07:07,980 --> 00:07:10,250
New ground-based telescope observations

144
00:07:10,250 --> 00:07:13,810
have identified 20 new moons orbiting Saturn,

145
00:07:13,810 --> 00:07:17,453
bringing the total to 82, beating Jupiter by three.

146
00:07:18,570 --> 00:07:21,580
So, we found these Saturn moons using the most powerful

147
00:07:21,580 --> 00:07:23,500
survey telescope in the world.

148
00:07:23,500 --> 00:07:26,963
It's the Subaru Telescope, which is eight meters in size,

149
00:07:27,880 --> 00:07:30,290
and it has the largest camera.

150
00:07:30,290 --> 00:07:32,750
It's the size of a small car, and it can cover

151
00:07:32,750 --> 00:07:35,190
six full moons in one image.

152
00:07:35,190 --> 00:07:37,190
And then, during the early source storm

153
00:07:37,190 --> 00:07:39,230
there's a lot of stuff flying around.

154
00:07:39,230 --> 00:07:40,860
There's a lot of comets and asteroids,

155
00:07:40,860 --> 00:07:42,660
many more than there are now,

156
00:07:42,660 --> 00:07:45,860
and so it's likely that these moons were hit

157
00:07:45,860 --> 00:07:49,997
by comets and asteroids that are just flying past Saturn.

158
00:07:49,997 --> 00:07:51,790
And that's why we see basically a lot of fragments

159
00:07:51,790 --> 00:07:53,959
from these collisions.

160
00:07:53,959 --> 00:07:54,792
(suspenseful music)

161
00:07:54,792 --> 00:07:57,330
The small moons, measuring only a few miles

162
00:07:57,330 --> 00:08:00,950
in size, orbit the outer edges of Saturn

163
00:08:00,950 --> 00:08:03,243
and many more could be hiding in plain sight.

164
00:08:04,640 --> 00:08:06,920
We're actually tracking more moons,

165
00:08:06,920 --> 00:08:08,690
and a lot of these moons are just on the edge

166
00:08:08,690 --> 00:08:10,990
of our detection, we can just barely see them.

167
00:08:11,990 --> 00:08:14,347
Saturn really is the moon king.

168
00:08:14,347 --> 00:08:16,847
(tense music)

169
00:08:17,690 --> 00:08:20,140
On February 1st, 2019,

170
00:08:20,140 --> 00:08:22,080
members of the Mars Exploration team

171
00:08:22,080 --> 00:08:24,110
gathered at NASA's JPL headquarters

172
00:08:24,110 --> 00:08:26,250
to say their final goodbye to one

173
00:08:26,250 --> 00:08:28,973
of space exploration's greatest pioneers,

174
00:08:29,920 --> 00:08:31,513
the Opportunity Rover.

175
00:08:32,910 --> 00:08:34,790
I wanted to say, with the completion

176
00:08:34,790 --> 00:08:37,770
of tonight's commanding, this concludes operations

177
00:08:37,770 --> 00:08:41,560
for MER-1 spacecraft ID 253.

178
00:08:41,560 --> 00:08:43,800
And on behalf of the entire MER project,

179
00:08:43,800 --> 00:08:47,180
we'd like to thank the DSN for over 15 1/2 years

180
00:08:47,180 --> 00:08:50,453
of outstanding support from launch until tonight.

181
00:08:51,420 --> 00:08:52,573
Thank you for your comments.

182
00:08:52,573 --> 00:08:53,983
Sad day for all of us.

183
00:08:54,818 --> 00:08:56,600
(somber music)

184
00:08:56,600 --> 00:08:58,223
14, you are released.

185
00:08:59,465 --> 00:09:02,560
(group applauding)

186
00:09:02,560 --> 00:09:05,100
It all began 15 years ago.

187
00:09:05,100 --> 00:09:07,782
The control room had a much different feel to it,

188
00:09:07,782 --> 00:09:08,615
(group cheering)

189
00:09:08,615 --> 00:09:11,853
one of excitement and, shall we say, opportunity.

190
00:09:12,820 --> 00:09:14,863
And it all started with one photo.

191
00:09:16,500 --> 00:09:18,780
When Opportunity sent back that first picture

192
00:09:18,780 --> 00:09:21,380
from Eagle Crater, that night is, like,

193
00:09:21,380 --> 00:09:23,500
burned in my brain, I will never forget it.

194
00:09:23,500 --> 00:09:26,210
It was such a dramatic image of Mars,

195
00:09:26,210 --> 00:09:30,150
and it was so different than any images we have seen before.

196
00:09:30,150 --> 00:09:33,260
(tense music)

197
00:09:33,260 --> 00:09:35,360
Opportunity, packed with tools

198
00:09:35,360 --> 00:09:38,120
and instruments was a wandering geologist

199
00:09:38,120 --> 00:09:40,530
probing the planet for information and searching

200
00:09:40,530 --> 00:09:42,023
for signs of liquid water.

201
00:09:43,562 --> 00:09:46,312
(probe whirring)

202
00:09:48,809 --> 00:09:51,190
Opportunity lands, right from the get go,

203
00:09:51,190 --> 00:09:53,500
discovery of water-formed rocks, right?

204
00:09:53,500 --> 00:09:55,600
Ya know, it came easy.

205
00:09:55,600 --> 00:09:58,510
Here, she found little so-called blueberries

206
00:09:58,510 --> 00:10:00,853
that contained hematite and iron ore.

207
00:10:01,720 --> 00:10:04,880
It's an iron mineral that forms in areas

208
00:10:04,880 --> 00:10:05,893
with a lot of water.

209
00:10:06,999 --> 00:10:09,553
(tense music)

210
00:10:09,553 --> 00:10:11,290
By the end, Opportunity traversed

211
00:10:11,290 --> 00:10:13,863
more than 28 miles of martian landscape,

212
00:10:15,070 --> 00:10:18,750
sharing more than 225,000 images of its surroundings

213
00:10:18,750 --> 00:10:20,300
with researchers back on Earth.

214
00:10:25,060 --> 00:10:28,680
Perseverance Valley, believed to be a water-formed gully,

215
00:10:28,680 --> 00:10:31,023
was Opportunity's final destination.

216
00:10:35,900 --> 00:10:40,450
It was here on June 10th, 2018, Sol 5111,

217
00:10:42,170 --> 00:10:45,010
that Opportunity sent its last message,

218
00:10:45,010 --> 00:10:48,667
creatively and poetically translated by media outlets as,

219
00:10:48,667 --> 00:10:51,737
"My battery is low and it's getting dark."

220
00:10:53,514 --> 00:10:54,920
(somber music)

221
00:10:54,920 --> 00:10:58,110
This as a massive and devastatingly dense

222
00:10:58,110 --> 00:10:59,483
dust storm approached.

223
00:11:01,320 --> 00:11:03,910
And so the robot couldn't generate any energy with that,

224
00:11:03,910 --> 00:11:06,490
and so, we saw the rover just shut down,

225
00:11:06,490 --> 00:11:08,580
and there was nothing we could do at that point

226
00:11:08,580 --> 00:11:12,000
because it didn't have power to keep going.

227
00:11:12,000 --> 00:11:13,623
And we just had to wait.

228
00:11:14,480 --> 00:11:18,293
And that's what we did do, is wait, and wait, and wait.

229
00:11:19,550 --> 00:11:21,800
This is its last panoramic view.

230
00:11:22,830 --> 00:11:27,530
Eight months later, NASA would designate Opportunity lost,

231
00:11:27,530 --> 00:11:29,782
its mission complete.

232
00:11:29,782 --> 00:11:31,490
(somber music)

233
00:11:31,490 --> 00:11:34,700
It taught us how to do surface operations.

234
00:11:34,700 --> 00:11:39,030
It taught us how to read the terrain and navigate

235
00:11:39,030 --> 00:11:42,210
and plot a safe path from one point to another.

236
00:11:42,210 --> 00:11:43,540
We did not know how to do those.

237
00:11:43,540 --> 00:11:45,010
It was all speculative.

238
00:11:45,010 --> 00:11:46,830
Three, two--
But new rovers

239
00:11:46,830 --> 00:11:48,318
are on the way.

240
00:11:48,318 --> 00:11:51,011
[Radio Controller] Zero, and liftoff of the Atlas V.

241
00:11:51,011 --> 00:11:51,844
(rocket jets boom)

242
00:11:51,844 --> 00:11:54,763
2019 was a very big year for Mars exploration.

243
00:11:55,870 --> 00:11:58,470
We've sent unmanned spacecraft to the fourth planet

244
00:11:58,470 --> 00:12:01,128
from the sun since the 1970s.

245
00:12:01,128 --> 00:12:02,980
(suspenseful music)

246
00:12:02,980 --> 00:12:05,500
But NASA's InSight is the first probe

247
00:12:05,500 --> 00:12:07,243
into the heart of the Red Planet.

248
00:12:10,120 --> 00:12:12,370
InSight uses cutting edge instruments

249
00:12:12,370 --> 00:12:14,780
to investigate internal processes

250
00:12:14,780 --> 00:12:17,723
that likely formed all of our terrestrial planets,

251
00:12:19,000 --> 00:12:22,603
taking Mars' daily temperature and planetary pulse.

252
00:12:24,770 --> 00:12:29,770
The basic idea of InSight is to map out the deep structure

253
00:12:29,800 --> 00:12:32,070
of Mars for the very first time.

254
00:12:32,070 --> 00:12:34,330
We're gonna map out the thickness of the crust,

255
00:12:34,330 --> 00:12:37,710
the size of the core, sort of get the first map

256
00:12:37,710 --> 00:12:39,563
of the inside of Mars.

257
00:12:40,810 --> 00:12:43,270
We don't know very much about what goes on

258
00:12:43,270 --> 00:12:45,270
2,000 miles below the surface,

259
00:12:45,270 --> 00:12:47,970
and this will be the first mission to investigate

260
00:12:47,970 --> 00:12:51,883
the huge extent of Mars below the surface.

261
00:12:51,883 --> 00:12:52,720
(soft music)

262
00:12:52,720 --> 00:12:54,260
But brand new technology

263
00:12:54,260 --> 00:12:55,603
doesn't come trouble-free.

264
00:12:56,820 --> 00:13:00,210
InSight's HP3, the mechanical mole designed

265
00:13:00,210 --> 00:13:03,110
to burrow 16 feet down into martian soil

266
00:13:03,110 --> 00:13:07,033
got stuck at just 12 inches down soon after landing.

267
00:13:09,037 --> 00:13:09,870
(tense music)

268
00:13:09,870 --> 00:13:13,350
Stuck on Earth, 140 million miles from Mars,

269
00:13:13,350 --> 00:13:15,060
engineers are working to determine

270
00:13:15,060 --> 00:13:17,080
if the stumbling block is a rock

271
00:13:17,080 --> 00:13:20,190
or if the problem lies with the unusual composition

272
00:13:20,190 --> 00:13:21,383
of the martian soil.

273
00:13:27,560 --> 00:13:31,260
The lander has detected several small Mars quakes.

274
00:13:31,260 --> 00:13:34,960
The tremors are much weaker than medium-sized earthquakes,

275
00:13:34,960 --> 00:13:38,810
confirming their suspicions that Mars is much more placid

276
00:13:38,810 --> 00:13:40,813
than tectonically-active Earth.

277
00:13:44,704 --> 00:13:48,650
(upbeat electronic music)

278
00:13:48,650 --> 00:13:51,300
NASA's family of fearless martian rovers

279
00:13:51,300 --> 00:13:54,250
have unlocked many of the Red Planet's secrets.

280
00:13:54,250 --> 00:13:57,033
From little Sojourner's first trip 22 years ago,

281
00:13:58,090 --> 00:14:00,910
to twins Spirit and Opportunity,

282
00:14:00,910 --> 00:14:03,053
and finally, the Curiosity rover.

283
00:14:03,890 --> 00:14:06,593
But it's time for a new generation of explorers.

284
00:14:07,560 --> 00:14:10,830
NASA plans to fly the first heavier-than-air spacecraft

285
00:14:10,830 --> 00:14:13,776
on another world, the Mars Helicopter.

286
00:14:13,776 --> 00:14:16,200
(helicopter whirring)

287
00:14:16,200 --> 00:14:19,166
The super bird is being tested right now.

288
00:14:19,166 --> 00:14:22,333
(helicopter whirring)

289
00:14:24,533 --> 00:14:27,550
We built the helicopter that'll go to Mars,

290
00:14:27,550 --> 00:14:30,920
and at this time we've shown that it can fly,

291
00:14:30,920 --> 00:14:33,370
we've done the flight test in the chamber

292
00:14:33,370 --> 00:14:36,283
with the thin atmosphere representative of Mars.

293
00:14:37,900 --> 00:14:41,120
In JPL's 25-foot wide vacuum chamber,

294
00:14:41,120 --> 00:14:43,420
the helicopter team recreated the gravity

295
00:14:43,420 --> 00:14:45,670
and flying conditions of the Red Planet

296
00:14:45,670 --> 00:14:47,363
to test the Mars helicopter.

297
00:14:48,560 --> 00:14:51,973
The vehicle's good to go for a July 2020 launch.

298
00:14:53,570 --> 00:14:55,790
But really, our job isn't done until we see

299
00:14:55,790 --> 00:14:59,900
the same test flight being performed at Mars.

300
00:14:59,900 --> 00:15:02,010
So, next time we fly it'll be on Mars,

301
00:15:02,010 --> 00:15:03,680
but that's our ultimate goal.

302
00:15:03,680 --> 00:15:06,106
That's when we'll go, "Yes." (chuckles)

303
00:15:06,106 --> 00:15:08,440
(soft tense music)

304
00:15:08,440 --> 00:15:10,180
Drones are the perfect way

305
00:15:10,180 --> 00:15:12,870
to investigate far-away worlds,

306
00:15:12,870 --> 00:15:16,740
especially in the search for extraterrestrial life.

307
00:15:16,740 --> 00:15:20,900
Titan, Saturn's largest moon, tantalizes scientists

308
00:15:20,900 --> 00:15:24,120
because it seems to hold all the ingredients for life

309
00:15:24,120 --> 00:15:26,163
that were present on early Earth.

310
00:15:27,047 --> 00:15:28,410
(soft tense music)

311
00:15:28,410 --> 00:15:30,920
And this year, a new mission has been approved

312
00:15:30,920 --> 00:15:33,310
to explore this alien world.

313
00:15:33,310 --> 00:15:37,003
NASA's Dragonfly drone is part of a new frontiers mission.

314
00:15:38,160 --> 00:15:41,020
The eight-rotor drone, expected to be the same size

315
00:15:41,020 --> 00:15:43,250
as the Curiosity Rover on Mars,

316
00:15:43,250 --> 00:15:45,810
will also carry many of the same instruments

317
00:15:45,810 --> 00:15:47,903
and will launch in 2026.

318
00:15:48,870 --> 00:15:52,520
Because Dragonfly will fly over instead of rolling on,

319
00:15:52,520 --> 00:15:55,410
it has the potential to cover far more territory.

320
00:15:55,410 --> 00:15:58,270
With speeds reaching 22 miles per hour,

321
00:15:58,270 --> 00:15:59,803
who knows what it will find.

322
00:16:01,510 --> 00:16:04,160
Dragonfly was designed to be a rotor craft

323
00:16:04,160 --> 00:16:05,730
to explore Titan because it's the right way

324
00:16:05,730 --> 00:16:07,130
to explore the Titan environment.

325
00:16:07,130 --> 00:16:09,580
It's the right way to make the measurements we need to

326
00:16:09,580 --> 00:16:12,540
to understand the chemistry oft this ocean world.

327
00:16:12,540 --> 00:16:15,080
There's sand dunes, there are clouds.

328
00:16:15,080 --> 00:16:16,390
You even have methane rain,

329
00:16:16,390 --> 00:16:19,100
there are methane rivers and lakes and seas.

330
00:16:19,100 --> 00:16:21,340
The organic chemistry in Titan's atmosphere

331
00:16:21,340 --> 00:16:24,110
and on its surface may replicate the type

332
00:16:24,110 --> 00:16:26,330
of organic chemistry we had here on Earth

333
00:16:26,330 --> 00:16:27,800
before life developed.

334
00:16:27,800 --> 00:16:30,860
We want to be able to understand how life took the step

335
00:16:30,860 --> 00:16:33,183
from chemistry to biology.

336
00:16:34,470 --> 00:16:36,090
While NASA and other agencies

337
00:16:36,090 --> 00:16:37,980
pioneer flight through space,

338
00:16:37,980 --> 00:16:41,320
78 years ago the first operational jet fighter plane

339
00:16:41,320 --> 00:16:44,330
was the engineering masterpiece of its time.

340
00:16:44,330 --> 00:16:48,090
The German Messerschmitt Me 262 set the course

341
00:16:48,090 --> 00:16:50,073
for the future of aviation history.

342
00:16:51,160 --> 00:16:53,030
If the Nazis had been able to access

343
00:16:53,030 --> 00:16:55,530
more refined metals for the jet's engines,

344
00:16:55,530 --> 00:16:59,200
if they'd had more fuel reserves and more time,

345
00:16:59,200 --> 00:17:01,110
then things might have played out very differently

346
00:17:01,110 --> 00:17:02,930
toward the end of World War II.

347
00:17:02,930 --> 00:17:05,600
Bomber crews had to have been terrified.

348
00:17:05,600 --> 00:17:09,289
The German airplane is almost 100 miles an hour faster.

349
00:17:09,289 --> 00:17:10,410
(jet engine roars)

350
00:17:10,410 --> 00:17:12,180
No one has flown a genuine example

351
00:17:12,180 --> 00:17:15,570
of this revolutionary machine since the 1950s,

352
00:17:15,570 --> 00:17:19,015
but it's now nearly ready to take to the skies once again.

353
00:17:19,015 --> 00:17:21,040
(bright orchestral music)

354
00:17:21,040 --> 00:17:23,630
It's been a 19-year effort to realize the dream

355
00:17:23,630 --> 00:17:25,350
of the late Vulcan founder

356
00:17:25,350 --> 00:17:28,070
and pioneer of Microsoft, Paul Allen,

357
00:17:28,070 --> 00:17:31,920
to restore the plane to precise historical accuracy.

358
00:17:31,920 --> 00:17:35,170
During the war, because of extreme pressure to win,

359
00:17:35,170 --> 00:17:37,570
that really accelerates the progress of technology

360
00:17:37,570 --> 00:17:39,290
and these engines are an example

361
00:17:39,290 --> 00:17:42,690
of the amazing leaps that happened because of that pressure.

362
00:17:42,690 --> 00:17:45,600
In 2000, the plane traveled across the world

363
00:17:45,600 --> 00:17:47,380
where engineers have stripped the plane down

364
00:17:47,380 --> 00:17:49,370
to its component parts.

365
00:17:49,370 --> 00:17:51,640
Basically, it came in a big wooden crate,

366
00:17:51,640 --> 00:17:53,293
pretty much just a rust bucket.

367
00:17:54,160 --> 00:17:57,763
Then painstakingly rebuilt it piece by piece.

368
00:18:01,030 --> 00:18:03,580
Up until the last year, we didn't know

369
00:18:03,580 --> 00:18:06,400
where the light at the end of the tunnel was.

370
00:18:06,400 --> 00:18:09,410
And with the success of the first engine tests,

371
00:18:09,410 --> 00:18:13,023
the Me 262 will attempt to take flight before year's end.

372
00:18:20,670 --> 00:18:23,337
(ominous music)

373
00:18:26,380 --> 00:18:29,150
A grim legacy of the same war has been discovered

374
00:18:29,150 --> 00:18:32,353
at a site of much earlier, but legendary tragedy.

375
00:18:40,350 --> 00:18:43,320
Over the years, archaeologists working in Pompeii,

376
00:18:43,320 --> 00:18:45,850
the famous archaeological sight, have discovered

377
00:18:45,850 --> 00:18:49,143
unexploded bombs dropped by the Allies in World War II.

378
00:18:50,240 --> 00:18:52,740
Another surfaced and was deactivated

379
00:18:52,740 --> 00:18:55,350
at the beginning of the first large-scale excavation

380
00:18:55,350 --> 00:18:59,750
in Pompeii in 70 years, nearly 2,000 years

381
00:18:59,750 --> 00:19:01,770
after the site was engulfed in ash

382
00:19:01,770 --> 00:19:03,773
by the eruption of Mt. Vesuvius.

383
00:19:07,970 --> 00:19:09,760
New finds at the famous site

384
00:19:09,760 --> 00:19:12,010
are rewriting everything we thought we knew

385
00:19:12,010 --> 00:19:15,400
about the deadly day in A.D. 79.

386
00:19:15,400 --> 00:19:18,480
Italian archaeologists have removed 24 feet

387
00:19:18,480 --> 00:19:22,530
of volcanic debris and have discovered brilliant murals

388
00:19:22,530 --> 00:19:26,201
and mosaics that remained hidden until now.

389
00:19:26,201 --> 00:19:27,610
(gentle music)

390
00:19:27,610 --> 00:19:30,260
New skeletons reveal more about the last minutes

391
00:19:30,260 --> 00:19:33,340
of aristocrats and slaves that never made it

392
00:19:33,340 --> 00:19:35,023
to the gates of the doomed city.

393
00:19:36,460 --> 00:19:38,700
But at the edge of the new excavation,

394
00:19:38,700 --> 00:19:40,040
archaeologists have discovered

395
00:19:40,040 --> 00:19:42,253
that they were not the first on site.

396
00:19:44,544 --> 00:19:45,630
(woman speaking in foreign language)

397
00:19:45,630 --> 00:19:48,480
In antiquity and even recent times,

398
00:19:48,480 --> 00:19:50,240
looters have dug a series of tunnels

399
00:19:50,240 --> 00:19:54,393
under the street into the stable of a once grand villa.

400
00:20:06,163 --> 00:20:07,060
(tense music)

401
00:20:07,060 --> 00:20:09,740
The tunnels, some as long as 60 meters,

402
00:20:09,740 --> 00:20:11,850
lead to neighboring homes.

403
00:20:11,850 --> 00:20:14,700
At night, using lanterns and lamps,

404
00:20:14,700 --> 00:20:16,410
the looters broke through the walls

405
00:20:16,410 --> 00:20:18,653
looking for precious objects of value.

406
00:20:38,668 --> 00:20:41,460
In contrast, archaeologists carefully remove

407
00:20:41,460 --> 00:20:45,060
the ash, layer by layer, searching for evidence

408
00:20:45,060 --> 00:20:46,163
of what happened here.

409
00:21:07,140 --> 00:21:08,280
The illegal diggers

410
00:21:08,280 --> 00:21:10,340
had partially cut through it,

411
00:21:10,340 --> 00:21:13,150
damaging the chance for a second mold.

412
00:21:13,150 --> 00:21:15,733
(somber music)

413
00:21:38,041 --> 00:21:40,791
(tools scraping)

414
00:22:10,286 --> 00:22:13,703
(soft suspenseful music)

415
00:22:26,720 --> 00:22:29,858
Mount Vesuvius is a stratovolcano

416
00:22:29,858 --> 00:22:33,370
and the deadly eruption produced six pyroclastic surges

417
00:22:33,370 --> 00:22:36,010
of fast-moving, ground-hugging waves

418
00:22:36,010 --> 00:22:38,783
of hot, toxic gases and ash.

419
00:22:40,370 --> 00:22:43,740
During the fourth surge, gas and pumice traveling

420
00:22:43,740 --> 00:22:46,260
at more than 150 miles per hour

421
00:22:46,260 --> 00:22:47,963
enveloped the city of Pompeii.

422
00:22:49,342 --> 00:22:51,560
(somber music)

423
00:22:51,560 --> 00:22:54,290
It's now known that most victims died instantly

424
00:22:54,290 --> 00:22:57,750
from the 600-degree super-heated air,

425
00:22:57,750 --> 00:22:59,870
but the ash continued to fall at the rate

426
00:22:59,870 --> 00:23:01,453
of six inches per hour.

427
00:23:05,510 --> 00:23:08,730
West of Vesuvius, Herculaneum escaped

428
00:23:08,730 --> 00:23:12,820
the first lethal blanketing, but just before midnight,

429
00:23:12,820 --> 00:23:17,820
another surge, this one a burning wall of volcanic mud,

430
00:23:17,950 --> 00:23:19,883
engulfed the smaller town.

431
00:23:21,930 --> 00:23:25,000
This pyroclastic flow quickly carbonized,

432
00:23:25,000 --> 00:23:28,270
encapsulating wood and other fragile materials

433
00:23:28,270 --> 00:23:30,293
with a thick black crust.

434
00:23:32,560 --> 00:23:35,280
Papyrus scrolls discovered in 1752

435
00:23:35,280 --> 00:23:37,720
were so fragile that every attempt

436
00:23:37,720 --> 00:23:39,460
to unwrap them through the centuries

437
00:23:39,460 --> 00:23:41,513
immediately caused them to crumble.

438
00:23:43,180 --> 00:23:46,340
These papyri are the only original literature

439
00:23:46,340 --> 00:23:49,300
to have survived from the classical world,

440
00:23:49,300 --> 00:23:52,413
so researchers are desperate to unwrap and read them.

441
00:23:54,840 --> 00:23:58,730
They are the canonical example of material

442
00:23:58,730 --> 00:24:01,850
from antiquity that is both too fragile

443
00:24:01,850 --> 00:24:05,590
to open and also so valuable and mysterious

444
00:24:05,590 --> 00:24:07,230
that it has captured the attention

445
00:24:07,230 --> 00:24:09,223
of scholars for many years.

446
00:24:10,140 --> 00:24:12,500
Now, by applying subatomic physics

447
00:24:12,500 --> 00:24:14,920
originally designed for medicine,

448
00:24:14,920 --> 00:24:16,583
they might have found a way.

449
00:24:17,450 --> 00:24:19,150
And then how many slices do you have to make up

450
00:24:19,150 --> 00:24:20,930
the whole run of the scroll?

451
00:24:20,930 --> 00:24:21,990
I mean, maybe 12,000?

452
00:24:21,990 --> 00:24:23,468
Right.

453
00:24:23,468 --> 00:24:25,213
That's a lotta data, right?

454
00:24:26,750 --> 00:24:28,460
Coupled with a surefire confidence

455
00:24:28,460 --> 00:24:31,140
in methodology, which drives Seales

456
00:24:31,140 --> 00:24:34,833
to his most ambitious projects and ultimate successes,

457
00:24:36,470 --> 00:24:39,540
including the 2016 virtual unwrapping

458
00:24:39,540 --> 00:24:41,730
of a third century Hebrew scroll

459
00:24:41,730 --> 00:24:43,523
known as the En-Gedi Scroll.

460
00:24:45,840 --> 00:24:48,940
Using X-ray to peer inside the badly damaged

461
00:24:48,940 --> 00:24:52,000
rolled up animal skin, Seales and his team

462
00:24:52,000 --> 00:24:54,520
laid out the artifact's geometric volume

463
00:24:54,520 --> 00:24:59,513
without ever opening it, highlighting the text within.

464
00:24:59,513 --> 00:25:02,096
(gentle music)

465
00:25:04,770 --> 00:25:07,120
The complex scanning of the Herculaneum scrolls

466
00:25:07,120 --> 00:25:10,930
took place over multiple days this summer in California

467
00:25:10,930 --> 00:25:14,010
as a team of international researchers held their breath

468
00:25:14,010 --> 00:25:15,879
as they unraveled history.

469
00:25:15,879 --> 00:25:18,796
(soft tense music)

470
00:25:20,460 --> 00:25:22,590
Well, you know, my expectations are always different

471
00:25:22,590 --> 00:25:23,450
from everyone else's.

472
00:25:23,450 --> 00:25:25,510
I expect things to happen quickly,

473
00:25:25,510 --> 00:25:27,930
but what's probably going to happen

474
00:25:27,930 --> 00:25:30,570
is that we will not see the complete text

475
00:25:30,570 --> 00:25:32,210
right away because there are too many

476
00:25:32,210 --> 00:25:35,460
computational steps involved in being really deliberate

477
00:25:35,460 --> 00:25:36,993
and systematic about our work.

478
00:25:37,970 --> 00:25:41,120
But when dealing with 2,000 year-old documents,

479
00:25:41,120 --> 00:25:44,133
what's a few months mean to learn the secrets held within?

480
00:25:45,480 --> 00:25:50,480
The prospect of noninvasively, virtually unwrapping

481
00:25:50,480 --> 00:25:53,030
these scrolls and reading their texts,

482
00:25:53,030 --> 00:25:55,700
is a very exciting breakthrough and scholars

483
00:25:55,700 --> 00:25:58,560
will potentially have access to a text

484
00:25:58,560 --> 00:26:02,023
that's complete, that's whole, and undamaged.

485
00:26:03,510 --> 00:26:08,510
If I could see one of our scrolls, seeing the writings,

486
00:26:11,354 --> 00:26:14,003
naturally, I'd jump for joy.

487
00:26:15,970 --> 00:26:18,103
What else? (chuckles)

488
00:26:19,540 --> 00:26:21,980
The scrolls are immensely valuable in the sense

489
00:26:21,980 --> 00:26:25,220
that it's the only library from antiquity

490
00:26:25,220 --> 00:26:28,300
that has ever been discovered in place.

491
00:26:28,300 --> 00:26:31,135
All libraries from antiquity have been lost.

492
00:26:31,135 --> 00:26:33,840
(ominous music)

493
00:26:33,840 --> 00:26:34,890
Throughout history,

494
00:26:34,890 --> 00:26:37,600
fire has been one of the most spontaneous

495
00:26:37,600 --> 00:26:40,717
and unstoppable forces of destruction.

496
00:26:42,073 --> 00:26:46,560
2019 saw a massive increase in wildfires around the globe.

497
00:26:46,560 --> 00:26:51,560
Siberia, Alaska, the Amazon, are all going up in smoke.

498
00:26:55,760 --> 00:26:57,790
Fast-moving fires can burn millions

499
00:26:57,790 --> 00:27:00,820
of acres of land and consume everything,

500
00:27:00,820 --> 00:27:04,409
trees, homes, even humans, in their paths.

501
00:27:04,409 --> 00:27:06,424
(tense music)

502
00:27:06,424 --> 00:27:07,300
(fireman chattering)

503
00:27:07,300 --> 00:27:10,530
Ongoing research in 2019 is revealing new

504
00:27:10,530 --> 00:27:13,563
and aggressive ways to combat wildfires.

505
00:27:14,940 --> 00:27:17,780
So, this vehicle is called the MSTAR,

506
00:27:17,780 --> 00:27:20,800
the Mobile Special Technology and Aerial Response.

507
00:27:20,800 --> 00:27:25,005
Typically we will carry one, two, three,

508
00:27:25,005 --> 00:27:26,963
four primary drones.

509
00:27:27,890 --> 00:27:30,553
You wanna get on scene and get a drone in the air quickly.

510
00:27:31,410 --> 00:27:33,880
The next phase in wildfire technology

511
00:27:33,880 --> 00:27:36,377
is integrating drone usage,

512
00:27:36,377 --> 00:27:39,680
and most likely it's used to map fires

513
00:27:39,680 --> 00:27:41,510
because you can put cameras on these,

514
00:27:41,510 --> 00:27:42,650
and you can put infrared cameras

515
00:27:42,650 --> 00:27:44,710
and you can fly in very complex terrain,

516
00:27:44,710 --> 00:27:47,200
smoky conditions, so that's a new tool

517
00:27:47,200 --> 00:27:49,760
that firefighters will be utilizing.

518
00:27:49,760 --> 00:27:52,900
Drone pilots go out, fly, to do mapping.

519
00:27:52,900 --> 00:27:54,300
They come back with an SD card

520
00:27:54,300 --> 00:27:56,080
that has all the pictures they've taken.

521
00:27:56,080 --> 00:27:58,070
I put it in my card reader.

522
00:27:58,070 --> 00:27:59,820
I'm using the software I have on here

523
00:27:59,820 --> 00:28:01,540
to go and stitch those things together,

524
00:28:01,540 --> 00:28:03,960
create an image, and maybe display that image

525
00:28:03,960 --> 00:28:05,740
outside to the commanders.

526
00:28:05,740 --> 00:28:08,240
(tense music)

527
00:28:12,290 --> 00:28:14,010
Meanwhile, this vehicle actually is equipped

528
00:28:14,010 --> 00:28:15,470
with many cameras.

529
00:28:15,470 --> 00:28:18,520
There's a camera on the front, the rear, and both sides

530
00:28:18,520 --> 00:28:20,200
as well as on top of the mast.

531
00:28:20,200 --> 00:28:23,040
So, I can see to maintain situational awareness

532
00:28:23,040 --> 00:28:25,400
of what's going on in the incident command post,

533
00:28:25,400 --> 00:28:26,720
but I can also at the same time see

534
00:28:26,720 --> 00:28:28,980
what the firefighters are doing on the inside of the fire.

535
00:28:28,980 --> 00:28:30,107
So, this could be my firefighters

536
00:28:30,107 --> 00:28:32,363
on the inside walking around.

537
00:28:34,180 --> 00:28:38,560
I think there's a lot of room for technology to improve

538
00:28:38,560 --> 00:28:41,230
the way that we fight wild land fires

539
00:28:41,230 --> 00:28:43,981
and the way that we prepare for wild land fires.

540
00:28:43,981 --> 00:28:44,814
(ominous music)

541
00:28:44,814 --> 00:28:48,460
Fire management agencies should be utilizing

542
00:28:48,460 --> 00:28:51,330
the current state of the science and technology.

543
00:28:51,330 --> 00:28:54,020
It takes a high-speed thermal camera,

544
00:28:54,020 --> 00:28:56,330
and then inside there's an optical frame.

545
00:28:56,330 --> 00:28:59,770
And if your vision is occluded by smoke,

546
00:28:59,770 --> 00:29:01,340
the thermal camera puts a green line

547
00:29:01,340 --> 00:29:03,770
around what you would be seeing.

548
00:29:03,770 --> 00:29:06,560
It's the small changes that make a big difference.

549
00:29:06,560 --> 00:29:08,410
Then your firefighters have a chance.

550
00:29:09,870 --> 00:29:11,270
If you look at the number of firefighters

551
00:29:11,270 --> 00:29:13,360
in the United States 30 years ago,

552
00:29:13,360 --> 00:29:14,650
it was about a million firefighters

553
00:29:14,650 --> 00:29:15,600
across the United States.

554
00:29:15,600 --> 00:29:18,020
Today, 30 years later, it's about a million-one,

555
00:29:18,020 --> 00:29:20,420
a million-two, almost the same number of firefighters,

556
00:29:20,420 --> 00:29:22,300
but the number of fires, number of incidents,

557
00:29:22,300 --> 00:29:24,193
number of calls have gone up.

558
00:29:25,330 --> 00:29:28,000
So, how do you get the point of doing more with less

559
00:29:28,000 --> 00:29:29,410
or more with the same?

560
00:29:29,410 --> 00:29:31,973
And the answer, of course, is technology.

561
00:29:32,950 --> 00:29:33,950
And no one could have used

562
00:29:33,950 --> 00:29:36,620
these advancements more than the brave souls combating

563
00:29:36,620 --> 00:29:39,726
this year's raging fires in South America.

564
00:29:39,726 --> 00:29:43,240
(soft tense music)

565
00:29:43,240 --> 00:29:46,580
The Amazon rainforest lost almost 4,000 square miles

566
00:29:46,580 --> 00:29:50,890
to fires in the first 26 days of August 2019 alone

567
00:29:50,890 --> 00:29:52,970
according to data from the Brazilian government's

568
00:29:52,970 --> 00:29:54,683
satellite monitoring agency.

569
00:29:56,320 --> 00:29:59,020
There is nobody here, there is nobody to stop it,

570
00:29:59,020 --> 00:30:01,943
and it just goes on for mile after mile.

571
00:30:01,943 --> 00:30:04,693
(fire crackling)

572
00:30:05,930 --> 00:30:08,290
The Amazon rainforest is over two million

573
00:30:08,290 --> 00:30:11,490
square miles of jungle in South America,

574
00:30:11,490 --> 00:30:12,853
billions of trees.

575
00:30:14,310 --> 00:30:16,870
But its health is important to the whole world.

576
00:30:16,870 --> 00:30:20,390
Without it, carbon dioxide would warm the atmosphere

577
00:30:20,390 --> 00:30:23,813
and oceans faster, changing weather patterns.

578
00:30:25,000 --> 00:30:27,760
The trees absorb and store carbon dioxide

579
00:30:27,760 --> 00:30:29,390
through their leaves.

580
00:30:29,390 --> 00:30:32,310
One tree can absorb the equivalent of a car burning

581
00:30:32,310 --> 00:30:37,220
eight liters of gasoline or 48 pounds per year.

582
00:30:37,220 --> 00:30:40,350
But when there's a mega drought coupled with fires,

583
00:30:40,350 --> 00:30:45,060
it stresses the forest and releases tons of carbon dioxide,

584
00:30:45,060 --> 00:30:47,133
contributing to the greenhouse effect.

585
00:30:48,460 --> 00:30:50,890
The canopy, of course, is where the plant

586
00:30:50,890 --> 00:30:53,110
is taking in carbon dioxide from the atmosphere,

587
00:30:53,110 --> 00:30:54,557
where the leaves are absorbing carbon dioxide

588
00:30:54,557 --> 00:30:57,920
and being stored up in the branches and the trunks

589
00:30:57,920 --> 00:30:59,433
and the roots.

590
00:30:59,433 --> 00:31:00,460
(upbeat music)

591
00:31:00,460 --> 00:31:03,810
The plants take out carbon and carbon dioxide

592
00:31:03,810 --> 00:31:05,233
and they release oxygen.

593
00:31:06,170 --> 00:31:08,940
All forests actually provide oxygen

594
00:31:08,940 --> 00:31:11,033
for the rest of life on Earth.

595
00:31:13,060 --> 00:31:15,500
This giant forest stores vast quantities

596
00:31:15,500 --> 00:31:16,733
of carbon dioxide.

597
00:31:17,750 --> 00:31:21,453
CO2 emissions are rising faster than models predict.

598
00:31:22,900 --> 00:31:25,650
Of the carbon dioxide we pump out ever year

599
00:31:25,650 --> 00:31:28,420
from factories, cars, power stations,

600
00:31:28,420 --> 00:31:32,670
and agricultural burn-offs, 40% is absorbed

601
00:31:32,670 --> 00:31:37,150
by the atmosphere, 30% is absorbed by the oceans,

602
00:31:37,150 --> 00:31:42,100
and 30% is absorbed and stored by forest ecosystems.

603
00:31:42,100 --> 00:31:44,260
The Amazon absorbs the largest amount

604
00:31:44,260 --> 00:31:47,207
of carbon of any rainforest in the world.

605
00:31:49,020 --> 00:31:51,690
With these mega fires occurring,

606
00:31:51,690 --> 00:31:54,540
the landscape is really a dark scenario

607
00:31:54,540 --> 00:31:56,945
I would say for the future of the Amazon.

608
00:31:56,945 --> 00:31:59,445
(tense music)

609
00:32:00,840 --> 00:32:02,470
Hundreds of billions of trees

610
00:32:02,470 --> 00:32:06,020
are going up in flames, and all these trees

611
00:32:06,020 --> 00:32:09,520
that once absorbed CO2, are now dead

612
00:32:09,520 --> 00:32:11,533
and releasing it into the atmosphere.

613
00:32:14,380 --> 00:32:17,430
The question is, will more fires push

614
00:32:17,430 --> 00:32:20,553
the Amazon rainforest to the point of no return?

615
00:32:22,220 --> 00:32:24,053
And how close are we already?

616
00:32:25,730 --> 00:32:28,470
Climate scientists say if temperatures do rise

617
00:32:28,470 --> 00:32:31,170
by three or four degrees this century,

618
00:32:31,170 --> 00:32:34,140
the Amazon rainforest won't absorb the great volumes

619
00:32:34,140 --> 00:32:38,530
of CO2 it currently does, or worse,

620
00:32:38,530 --> 00:32:42,400
it'll begin to produce more CO2 than it absorbs

621
00:32:42,400 --> 00:32:45,203
and our planet as we know it will change forever.

622
00:32:47,230 --> 00:32:49,710
Already, climate change is having a grim effect

623
00:32:49,710 --> 00:32:50,913
on our fragile planet.

624
00:32:53,210 --> 00:32:55,960
July 2019 was the hottest month

625
00:32:55,960 --> 00:32:57,943
in recorded history for our planet.

626
00:32:59,463 --> 00:33:00,830
(ice crashing)

627
00:33:00,830 --> 00:33:04,470
According to Noah, polar ice melted to record lows

628
00:33:04,470 --> 00:33:07,633
while worldwide summer temperatures soared to new heights.

629
00:33:09,700 --> 00:33:12,770
Earth has experienced global warming in the past,

630
00:33:12,770 --> 00:33:15,855
but never at this speed and with this intensity.

631
00:33:15,855 --> 00:33:17,690
(upbeat music)

632
00:33:17,690 --> 00:33:21,633
It begs the question, what lifeforms will be left on Earth?

633
00:33:22,570 --> 00:33:24,913
Possibly parasites.

634
00:33:25,820 --> 00:33:28,380
Groundbreaking research reveals that creatures

635
00:33:28,380 --> 00:33:32,040
that live on other organisms at the expense of their hosts

636
00:33:32,040 --> 00:33:34,653
make up half of all known species on Earth.

637
00:33:35,770 --> 00:33:38,350
Being a parasitologist, it's sort of like

638
00:33:38,350 --> 00:33:40,210
every day is your birthday.

639
00:33:40,210 --> 00:33:41,740
You have this present in front of you

640
00:33:41,740 --> 00:33:43,140
and you open it up, you don't know

641
00:33:43,140 --> 00:33:45,680
what's gonna be inside it, but usually it's something cool.

642
00:33:45,680 --> 00:33:48,577
This is a jar of raccoon roundworms.

643
00:33:48,577 --> 00:33:50,000
Sometimes it's something you've never seen before.

644
00:33:50,000 --> 00:33:51,860
Sometimes it might be something that nobody

645
00:33:51,860 --> 00:33:52,910
has ever seen before.

646
00:33:54,680 --> 00:33:56,590
Parasites can be deadly.

647
00:33:56,590 --> 00:33:58,790
In 2017, malaria caused

648
00:33:58,790 --> 00:34:02,740
an estimated 435,000 deaths globally,

649
00:34:02,740 --> 00:34:06,283
almost 85% occurring in Africa and India.

650
00:34:07,780 --> 00:34:10,110
However, parasites in the salt marshes

651
00:34:10,110 --> 00:34:12,390
of Southern California may help paint

652
00:34:12,390 --> 00:34:15,803
a broader picture of how they fit into our ecosystem.

653
00:34:17,330 --> 00:34:18,460
One of the things that we've learned

654
00:34:18,460 --> 00:34:21,170
is that parasites are really everywhere.

655
00:34:21,170 --> 00:34:24,610
There are so many parasites around us all the time

656
00:34:24,610 --> 00:34:25,939
that we just don't see.

657
00:34:25,939 --> 00:34:26,772
(tense music)

658
00:34:26,772 --> 00:34:30,480
You've got this species of snail that's basically

659
00:34:30,480 --> 00:34:33,890
hundreds per square meter sometimes like this,

660
00:34:33,890 --> 00:34:37,310
and then the trematodes that are in most of these guys,

661
00:34:37,310 --> 00:34:40,720
we think, they castrate the snail for life.

662
00:34:40,720 --> 00:34:41,940
So, they're sitting in the gonads

663
00:34:41,940 --> 00:34:44,280
and they multiply asexually and they fill up

664
00:34:44,280 --> 00:34:45,610
the gonads and they just munch away

665
00:34:45,610 --> 00:34:47,000
as the new gonads produce.

666
00:34:47,000 --> 00:34:48,570
And then if you open up an infected one,

667
00:34:48,570 --> 00:34:51,290
it's just this mass of worms in place

668
00:34:51,290 --> 00:34:54,000
of where the gonads should be, and as far as we know,

669
00:34:54,000 --> 00:34:56,120
the snail doesn't notice the difference.

670
00:34:56,120 --> 00:34:57,070
Yeah.
And instead of

671
00:34:57,070 --> 00:34:59,763
making snail babies, it makes parasite babies.

672
00:35:01,530 --> 00:35:04,580
Most of the parasites' extreme adaptations

673
00:35:04,580 --> 00:35:06,583
are ultimately about reproduction.

674
00:35:09,050 --> 00:35:10,480
The larvae in the snails grow

675
00:35:10,480 --> 00:35:12,760
into a trematode worm that keeps moving

676
00:35:12,760 --> 00:35:15,510
from one host to another as it develops.

677
00:35:15,510 --> 00:35:18,950
Since it can reproduce only in the gut of shore birds,

678
00:35:18,950 --> 00:35:22,070
it makes the transition through an unusual route:

679
00:35:22,070 --> 00:35:23,763
the brain of a fish.

680
00:35:25,260 --> 00:35:27,830
What we think is that this parasite has had

681
00:35:27,830 --> 00:35:30,730
this adaptation to basically sit on the brain

682
00:35:30,730 --> 00:35:32,910
of the fish, control its behavior,

683
00:35:32,910 --> 00:35:36,300
mind control in a way, and that puts the parasite

684
00:35:36,300 --> 00:35:39,210
in the driver's seat because when they're infected

685
00:35:39,210 --> 00:35:41,633
they'll do things like they'll roll over

686
00:35:41,633 --> 00:35:45,940
and show that bright white belly up in the air

687
00:35:45,940 --> 00:35:48,453
so a predatory bird is more likely to see them.

688
00:35:50,090 --> 00:35:52,720
The parasite's not using a sledgehammer to do this.

689
00:35:52,720 --> 00:35:56,653
It's using finely-tuned chemical manipulation.

690
00:35:58,580 --> 00:36:01,410
The unlikely odyssey of the trematode parasites

691
00:36:01,410 --> 00:36:04,860
doesn't come to an end when they reach the bellies of birds.

692
00:36:04,860 --> 00:36:07,240
The cycle begins all over again as the birds

693
00:36:07,240 --> 00:36:10,920
spread millions of parasite eggs in their droppings.

694
00:36:10,920 --> 00:36:12,780
You know, the birds are really the top

695
00:36:12,780 --> 00:36:15,640
of the food chain here, and of course in doing that,

696
00:36:15,640 --> 00:36:17,937
they're also the final host for so many

697
00:36:17,937 --> 00:36:20,240
of the parasites that are out here.

698
00:36:20,240 --> 00:36:22,590
There's just as much parasite biomass

699
00:36:22,590 --> 00:36:25,270
in this salt marsh as there is bird biomass.

700
00:36:25,270 --> 00:36:27,070
So, to the extent that we think that the birds

701
00:36:27,070 --> 00:36:29,560
are important players in the salt marsh,

702
00:36:29,560 --> 00:36:31,470
then I think we also have to think of the parasites

703
00:36:31,470 --> 00:36:33,070
as being important players, too.

704
00:36:34,170 --> 00:36:35,760
It may take us some time to get used

705
00:36:35,760 --> 00:36:38,330
to the idea that parasites are a vital part

706
00:36:38,330 --> 00:36:39,823
of every ecosystem.

707
00:36:42,149 --> 00:36:43,450
(gentle music)

708
00:36:43,450 --> 00:36:47,140
252 million years ago humans weren't around

709
00:36:47,140 --> 00:36:50,483
to impact which species failed and which thrived.

710
00:36:52,230 --> 00:36:54,710
Paleontologists in Norway just discovered

711
00:36:54,710 --> 00:36:57,860
that after the Permian-Triassic mass extinction,

712
00:36:57,860 --> 00:37:01,100
life recovered twice as fast in the polar regions

713
00:37:01,100 --> 00:37:02,523
than elsewhere on Earth.

714
00:37:04,031 --> 00:37:06,240
(bright music)

715
00:37:06,240 --> 00:37:09,473
How quickly can life recover after a global catastrophe?

716
00:37:11,240 --> 00:37:13,370
Answers may lie in the fossil record

717
00:37:13,370 --> 00:37:14,773
at the top of the world.

718
00:37:15,970 --> 00:37:17,390
Scientists are looking at the world's

719
00:37:17,390 --> 00:37:19,310
biggest extinction event for clues

720
00:37:19,310 --> 00:37:21,143
about which species survived.

721
00:37:22,850 --> 00:37:25,570
When we're talking about an extinction in paleontology,

722
00:37:25,570 --> 00:37:27,273
it means total extinction.

723
00:37:28,390 --> 00:37:32,103
And it almost wiped the whole blackboard completely.

724
00:37:33,290 --> 00:37:36,463
It happened 252 million years ago.

725
00:37:38,360 --> 00:37:41,630
It was not only a regional disaster,

726
00:37:41,630 --> 00:37:44,220
but it was really the biggest disaster

727
00:37:44,220 --> 00:37:46,070
in Earth's history.

728
00:37:46,070 --> 00:37:47,840
And of course there were life on land,

729
00:37:47,840 --> 00:37:50,430
there were life in the ocean at that time,

730
00:37:50,430 --> 00:37:51,973
and most of it got extinct.

731
00:37:52,864 --> 00:37:55,531
(ominous music)

732
00:37:57,580 --> 00:38:01,370
About 252 million years ago on the border

733
00:38:01,370 --> 00:38:03,346
between what we call the Permian

734
00:38:03,346 --> 00:38:05,383
and the Triassic time periods,

735
00:38:05,383 --> 00:38:06,730
(volcano booms)

736
00:38:06,730 --> 00:38:10,880
the biggest volcanic eruptions in Earth's history happened,

737
00:38:10,880 --> 00:38:14,940
and an area was covered in Siberia that was

738
00:38:14,940 --> 00:38:17,173
between the size of India and Australia.

739
00:38:18,060 --> 00:38:21,830
And not only it was this big, but it was also thick.

740
00:38:21,830 --> 00:38:24,790
The thickness of this volcanic eruption, all the things

741
00:38:24,790 --> 00:38:26,720
that came up through the volcanoes

742
00:38:26,720 --> 00:38:29,873
was about 2,000 meters if we average it.

743
00:38:30,880 --> 00:38:32,934
That's over one-mile thick.

744
00:38:32,934 --> 00:38:34,290
(dramatic music)

745
00:38:34,290 --> 00:38:37,633
Molten lava continued to spew for several million years,

746
00:38:38,900 --> 00:38:41,283
but it wasn't just the inferno that was deadly.

747
00:38:42,800 --> 00:38:46,173
The volcanics came in contact with evaporites.

748
00:38:47,200 --> 00:38:49,750
There had been a large sea in the area

749
00:38:49,750 --> 00:38:53,580
that completely dried out, like the Dead Sea today.

750
00:38:53,580 --> 00:38:55,970
So, you have big salt layers,

751
00:38:55,970 --> 00:38:58,610
and of course if you boil salt,

752
00:38:58,610 --> 00:39:02,812
you get a lot of nasty things because salt

753
00:39:02,812 --> 00:39:05,410
is a lot of chloride, and when you start

754
00:39:05,410 --> 00:39:09,370
to boil chloride you get a gas that's really poisonous,

755
00:39:09,370 --> 00:39:11,920
and there's always some sulfur,

756
00:39:11,920 --> 00:39:15,260
and if you start to boil the sulfur stuff,

757
00:39:15,260 --> 00:39:19,963
you get poisons and you get acids, sulfuric acid.

758
00:39:21,456 --> 00:39:24,206
(dramatic music)

759
00:39:25,143 --> 00:39:28,633
Everything on land and in the sea was affected.

760
00:39:31,200 --> 00:39:35,453
And suddenly we see in the rock layers mud,

761
00:39:36,290 --> 00:39:38,473
just dark, gray mud.

762
00:39:42,020 --> 00:39:45,500
And we can start to dig in it and we can see

763
00:39:45,500 --> 00:39:48,820
that there's almost no life.

764
00:39:48,820 --> 00:39:51,703
It's just covered with dead mud.

765
00:39:52,930 --> 00:39:54,800
The dramatic end of the Permian

766
00:39:54,800 --> 00:39:56,403
is known as the Great Dying,

767
00:39:57,670 --> 00:39:59,593
and the ocean suffered the most.

768
00:40:00,900 --> 00:40:05,110
But something between 82 and 96% of all species

769
00:40:05,110 --> 00:40:07,833
in the ocean everywhere got extinct.

770
00:40:09,730 --> 00:40:12,080
Even hearty, iconic species

771
00:40:12,080 --> 00:40:14,713
like trilobites vanished forever.

772
00:40:17,000 --> 00:40:19,430
The disaster was so nearly complete

773
00:40:19,430 --> 00:40:22,100
that in most places it would take 10 million years

774
00:40:22,100 --> 00:40:23,293
for life to recover.

775
00:40:24,750 --> 00:40:28,090
The period that begins just after the Permian Extinction,

776
00:40:28,090 --> 00:40:32,553
252 million years ago, is known as the Mesozoic Era.

777
00:40:35,140 --> 00:40:38,220
Through some wonderful work done by Chinese

778
00:40:38,220 --> 00:40:41,220
and English paleontologists for many years,

779
00:40:41,220 --> 00:40:43,870
they see that life slowly appears again,

780
00:40:43,870 --> 00:40:46,610
but the complex ecosystems that you see

781
00:40:46,610 --> 00:40:49,640
for the rest of the Mesozoic, they only appear

782
00:40:49,640 --> 00:40:50,873
after 10 million years.

783
00:40:52,550 --> 00:40:54,840
While Chinese and English paleontologists

784
00:40:54,840 --> 00:40:58,240
have calculated the recovery at 10 million years,

785
00:40:58,240 --> 00:41:00,490
Jorn and his team have searched the shale layers

786
00:41:00,490 --> 00:41:04,840
on Svalbard and found that recovery was much faster.

787
00:41:04,840 --> 00:41:06,480
(tense music)

788
00:41:06,480 --> 00:41:10,103
We are down to at least half the time.

789
00:41:11,060 --> 00:41:13,810
For the scientists, this was a revelation.

790
00:41:15,160 --> 00:41:17,520
So, in China, 10 million years.

791
00:41:17,520 --> 00:41:20,040
In Svalbard, five million years

792
00:41:20,040 --> 00:41:22,370
to a full ecosystem with top predators.

793
00:41:22,370 --> 00:41:26,113
We are trying now to push it down to four million years

794
00:41:26,113 --> 00:41:27,080
after the extinction.

795
00:41:27,080 --> 00:41:29,070
So, then it's six million-year gap

796
00:41:29,944 --> 00:41:33,430
between a large ecosystem close to the equator,

797
00:41:33,430 --> 00:41:36,370
and one on the northern end of the Pangaea.

798
00:41:36,370 --> 00:41:39,040
In Svalbard we see that things are moving

799
00:41:39,040 --> 00:41:40,943
much faster back to a recovery.

800
00:41:41,830 --> 00:41:43,270
The scientists don't yet know

801
00:41:43,270 --> 00:41:45,500
why this is the case, but they're determined

802
00:41:45,500 --> 00:41:46,563
to solve the mystery.

803
00:41:49,390 --> 00:41:51,220
Jorn and his team are the first to document

804
00:41:51,220 --> 00:41:53,530
this transition in northern Pangaea,

805
00:41:53,530 --> 00:41:56,573
five million years earlier than researchers thought.

806
00:41:57,680 --> 00:42:00,200
It's extremely fast evolution.

807
00:42:00,200 --> 00:42:05,070
We see the disaster taxa, we still see the bone fishes,

808
00:42:05,070 --> 00:42:08,120
then we see the marine amphibians,

809
00:42:08,120 --> 00:42:12,770
but then we also have the first marine reptiles

810
00:42:12,770 --> 00:42:14,780
in the same layer, and this is something

811
00:42:14,780 --> 00:42:16,980
that's quite spectacular for us to see,

812
00:42:16,980 --> 00:42:20,850
that actually we have the mix, we have the change.

813
00:42:20,850 --> 00:42:24,260
This is when we go from an environment

814
00:42:24,260 --> 00:42:28,440
that's just extremely strange because it's just after

815
00:42:28,440 --> 00:42:30,790
the big extinction into something

816
00:42:30,790 --> 00:42:35,653
that starts to hint towards a normal Mesozoic ecosystem.

817
00:42:36,800 --> 00:42:38,930
No matter how quickly life bounces back

818
00:42:38,930 --> 00:42:41,360
after pushing the reset button, it still takes

819
00:42:41,360 --> 00:42:44,863
millions of years before complete ecosystems thrive again.

820
00:42:46,030 --> 00:42:48,603
This has striking implications for Earth today.

821
00:42:49,560 --> 00:42:51,370
As we confront the climate crisis

822
00:42:51,370 --> 00:42:53,550
and increasing habitat destruction,

823
00:42:53,550 --> 00:42:56,540
we're seeing a pattern that parallels prehistory

824
00:42:56,540 --> 00:42:57,753
at warp speed.

825
00:42:59,720 --> 00:43:01,550
It's part of the impetus for scientists

826
00:43:01,550 --> 00:43:04,990
to decode the genomes of iconic extinct species

827
00:43:04,990 --> 00:43:08,680
and make plans to resurrect them within our lifetime.

828
00:43:08,680 --> 00:43:11,770
Thylacines once roamed throughout Australia

829
00:43:11,770 --> 00:43:13,960
and a breakthrough in Melbourne may see them

830
00:43:13,960 --> 00:43:17,093
hunting in Tasmanian forests again soon.

831
00:43:19,592 --> 00:43:20,830
(bright music)

832
00:43:20,830 --> 00:43:23,970
Andrew Pask is an expert in developmental genetics

833
00:43:23,970 --> 00:43:24,923
in Australia.

834
00:43:26,300 --> 00:43:28,870
His team made a huge breakthrough by sequencing

835
00:43:28,870 --> 00:43:32,290
the entire thylacine genome, but where did they get

836
00:43:32,290 --> 00:43:33,733
the thylacine DNA?

837
00:43:34,640 --> 00:43:36,210
Because people were going out and killing them

838
00:43:36,210 --> 00:43:38,810
on such a large scale, museums were really

839
00:43:38,810 --> 00:43:40,210
trying to collect specimens.

840
00:43:40,210 --> 00:43:42,720
They knew they were disappearing from the wild.

841
00:43:42,720 --> 00:43:45,470
And, in some rare circumstances, there were females

842
00:43:45,470 --> 00:43:48,640
that were shot that still had babies in their pouch,

843
00:43:48,640 --> 00:43:51,540
and then those babies made it into museum collections.

844
00:43:51,540 --> 00:43:53,710
And that's what really enabled us to start looking

845
00:43:53,710 --> 00:43:56,139
into the biology of the thylacine.

846
00:43:56,139 --> 00:43:57,260
(tense music)

847
00:43:57,260 --> 00:43:59,140
DNA from the Melbourne specimen

848
00:43:59,140 --> 00:44:01,270
had sequences long enough to recreate

849
00:44:01,270 --> 00:44:04,963
the entire three-billion letter genome of the thylacine.

850
00:44:06,140 --> 00:44:08,640
But Pask and his team needed to isolate

851
00:44:08,640 --> 00:44:11,310
specific genes from the DNA strings

852
00:44:11,310 --> 00:44:13,163
for the next phase of their research.

853
00:44:14,290 --> 00:44:16,820
De-extinction and trying to bring an animal back to life

854
00:44:16,820 --> 00:44:19,310
is very different from animal cloning.

855
00:44:19,310 --> 00:44:22,210
Animal cloning's something we're very good at today,

856
00:44:22,210 --> 00:44:25,160
and that process you have to start with a living cell,

857
00:44:25,160 --> 00:44:28,450
and you can put that living cell into an embryo

858
00:44:28,450 --> 00:44:29,900
and you can use that living cell then

859
00:44:29,900 --> 00:44:32,980
to generate a whole 'nother individual or clone

860
00:44:32,980 --> 00:44:35,480
of where that cell originally came from.

861
00:44:35,480 --> 00:44:37,740
The key thing for any of these sorts of technologies

862
00:44:37,740 --> 00:44:39,580
of bringing an animal back, is you have

863
00:44:39,580 --> 00:44:41,500
to start with a living cell.

864
00:44:41,500 --> 00:44:44,170
So, although we have the complete genetic blueprint

865
00:44:44,170 --> 00:44:47,210
of a thylacine, this is letters on a computer screen.

866
00:44:47,210 --> 00:44:49,398
This is not a living cell.

867
00:44:49,398 --> 00:44:51,120
(gentle music)

868
00:44:51,120 --> 00:44:54,140
There's a new technology called CRISPR-Cas line technology.

869
00:44:54,140 --> 00:44:57,590
It's a DNA editing tool that we now have

870
00:44:57,590 --> 00:45:00,280
that enables you to make those edits.

871
00:45:00,280 --> 00:45:02,160
The number edits that you have to make

872
00:45:02,160 --> 00:45:04,703
is in the order of millions of edits.

873
00:45:05,880 --> 00:45:08,010
The next step in Andrew Pask's journey

874
00:45:08,010 --> 00:45:09,930
through Jurassic Park down under,

875
00:45:09,930 --> 00:45:12,850
will be to create a living thylacine genome

876
00:45:12,850 --> 00:45:15,913
by modifying the genome of a close living relative.

877
00:45:17,100 --> 00:45:20,240
We can start to think about surrogate species

878
00:45:20,240 --> 00:45:22,330
that we would use to genome edit

879
00:45:22,330 --> 00:45:24,380
to make them look like a thylacine,

880
00:45:24,380 --> 00:45:26,530
but the really big problem with the thylacine then

881
00:45:26,530 --> 00:45:28,920
would be transferring that embryo

882
00:45:28,920 --> 00:45:31,390
into another marsupial surrogate mother

883
00:45:31,390 --> 00:45:33,020
that would then have to give birth

884
00:45:33,020 --> 00:45:35,263
to a thylacine pouch young.

885
00:45:37,210 --> 00:45:40,340
Pask thinks that Western Australia's Numbat

886
00:45:40,340 --> 00:45:43,293
might provide the best starting DNA blueprint.

887
00:45:44,240 --> 00:45:47,710
It's one of the thylacine's closest living relatives,

888
00:45:47,710 --> 00:45:51,313
last sharing a common ancestor 30 million years ago.

889
00:45:52,410 --> 00:45:56,070
The termite-eating creature also has stripes,

890
00:45:56,070 --> 00:45:59,170
but adults are only slightly bigger than a squirrel,

891
00:45:59,170 --> 00:46:01,963
where adult thylacines were much bigger.

892
00:46:03,690 --> 00:46:05,520
Numbats are the closest living relative

893
00:46:05,520 --> 00:46:09,050
to the thylacine, but unfortunately,

894
00:46:09,050 --> 00:46:11,560
these are insectivores, so they obviously

895
00:46:11,560 --> 00:46:14,540
have a very different digestive system,

896
00:46:14,540 --> 00:46:16,940
so they obviously have a huge amount of differences

897
00:46:16,940 --> 00:46:19,480
between their genomes, and that makes our job

898
00:46:19,480 --> 00:46:21,080
a lot harder because you would have to make

899
00:46:21,080 --> 00:46:24,840
many, many more of those edits to the blueprint

900
00:46:24,840 --> 00:46:29,720
to make our thylacine genome really come back to life.

901
00:46:29,720 --> 00:46:31,370
Why go to all this trouble

902
00:46:31,370 --> 00:46:34,033
to bring back an animal that's already extinct?

903
00:46:35,350 --> 00:46:36,930
It's one of the few animals that we know

904
00:46:36,930 --> 00:46:39,270
the exact moment that the last animal died

905
00:46:39,270 --> 00:46:42,820
and that species went completely extinct from our planet,

906
00:46:42,820 --> 00:46:45,030
and it's got this really sad story of extinction

907
00:46:45,030 --> 00:46:46,980
where we aggressively hunted this animal

908
00:46:46,980 --> 00:46:48,403
to extinction in the wild.

909
00:46:49,620 --> 00:46:52,060
The end goal of this de-extinction effort

910
00:46:52,060 --> 00:46:54,250
will be to reintroduce the thylacines

911
00:46:54,250 --> 00:46:56,650
to the wild reserves that cover about half

912
00:46:56,650 --> 00:46:57,933
of Tasmania today.

913
00:46:59,210 --> 00:47:01,440
With the thylacine, it's really a great example

914
00:47:01,440 --> 00:47:03,740
of a species that you could just pop back

915
00:47:03,740 --> 00:47:05,330
into the ecosystem in Tasmania,

916
00:47:05,330 --> 00:47:07,550
and it certainly has everything it needs there

917
00:47:07,550 --> 00:47:09,440
in order to not just survive,

918
00:47:09,440 --> 00:47:11,830
but also thrive in that environment.

919
00:47:11,830 --> 00:47:13,760
(upbeat music)

920
00:47:13,760 --> 00:47:16,250
Tremendous progress was made in 2019

921
00:47:16,250 --> 00:47:19,410
in the fields of genetic and biomedical engineering.

922
00:47:19,410 --> 00:47:22,230
Science can now construct the facial features

923
00:47:22,230 --> 00:47:25,623
of suspects who leave DNA at the scene of their crimes.

924
00:47:27,810 --> 00:47:29,720
They're decoding what was formerly thought

925
00:47:29,720 --> 00:47:33,550
to be junk DNA to reveal more than 10,000 markers

926
00:47:33,550 --> 00:47:35,003
for facial recognition.

927
00:47:37,080 --> 00:47:39,460
Our DNA is key to so many aspects

928
00:47:39,460 --> 00:47:42,253
of our appearances and our health.

929
00:47:47,110 --> 00:47:49,440
Heart disease is the number one cause of death

930
00:47:49,440 --> 00:47:51,223
for our species worldwide.

931
00:47:52,420 --> 00:47:54,790
That's why researchers are trailblazing ways

932
00:47:54,790 --> 00:47:59,725
to repair hearts through gene manipulation to 3D printing.

933
00:47:59,725 --> 00:48:02,225
(tense music)

934
00:48:03,487 --> 00:48:05,780
All around the world, researchers are determined

935
00:48:05,780 --> 00:48:07,743
to learn how to fix a broken heart,

936
00:48:09,550 --> 00:48:11,970
exploring multiple paths of inquiry

937
00:48:11,970 --> 00:48:14,563
to innovate new bioengineering methods,

938
00:48:15,880 --> 00:48:19,423
even developing the technology to print a new heart.

939
00:48:21,610 --> 00:48:24,793
The process of healing occurs very slowly in the heart.

940
00:48:26,610 --> 00:48:29,370
It's believed that only 30% of its cells

941
00:48:29,370 --> 00:48:31,893
are replaced over 50 years.

942
00:48:34,660 --> 00:48:37,920
So, once the heart is damaged, it takes a long time

943
00:48:37,920 --> 00:48:39,513
for recovery to take place.

944
00:48:41,100 --> 00:48:43,583
How can new heart cells be generated?

945
00:48:44,540 --> 00:48:49,110
It appears tiny extracellular bubbles called exosomes,

946
00:48:49,110 --> 00:48:53,040
some hidden within the heart, play a key role.

947
00:48:53,040 --> 00:48:55,763
They contain a message that can rebuild the heart.

948
00:49:00,710 --> 00:49:03,720
Renowned researcher, Dr. Eduardo Marban,

949
00:49:03,720 --> 00:49:06,560
tested this theory by giving with mice

950
00:49:06,560 --> 00:49:08,883
that had experienced cardiac infarction.

951
00:49:10,380 --> 00:49:12,303
The results were dramatic.

952
00:49:13,700 --> 00:49:16,983
This is the wall of the heart after cardiac infarction.

953
00:49:18,010 --> 00:49:20,110
The cells on the right side have died

954
00:49:21,000 --> 00:49:22,723
and the wall has become thin.

955
00:49:25,280 --> 00:49:27,900
But in mice that received these additional

956
00:49:27,900 --> 00:49:31,080
messaging molecules, the number of cells

957
00:49:31,080 --> 00:49:34,153
had increased and the wall had become thicker.

958
00:49:36,010 --> 00:49:38,560
They might be very powerful agents

959
00:49:38,560 --> 00:49:40,410
in the treatment of disease in a way

960
00:49:40,410 --> 00:49:43,817
that defies all the conventions.

961
00:49:43,817 --> 00:49:45,130
(tense music)

962
00:49:45,130 --> 00:49:47,330
Elsewhere, researchers investigate

963
00:49:47,330 --> 00:49:50,120
other approaches, including the development

964
00:49:50,120 --> 00:49:52,823
of lab-cultured tissues and organs.

965
00:49:54,512 --> 00:49:56,540
(tense music)

966
00:49:56,540 --> 00:49:59,920
This is Kenneth Chien, a world-leading expert

967
00:49:59,920 --> 00:50:01,913
in the field of regenerative medicine.

968
00:50:03,410 --> 00:50:06,660
Here, the researcher adds a certain signaling molecule

969
00:50:06,660 --> 00:50:07,993
to an ES cell.

970
00:50:09,210 --> 00:50:11,483
It's called Wnt.

971
00:50:12,850 --> 00:50:15,630
Wnt molecules are present in large quantities

972
00:50:15,630 --> 00:50:16,913
in dividing eggs.

973
00:50:20,610 --> 00:50:21,627
After one week,

974
00:50:21,627 --> 00:50:22,730
(scientist chattering)

975
00:50:22,730 --> 00:50:24,693
part of the cell is starting to pulse.

976
00:50:33,790 --> 00:50:36,750
Two days later, large ripples

977
00:50:36,750 --> 00:50:38,623
move across the flattened cell.

978
00:50:47,130 --> 00:50:49,793
This is the very beginning of a human heart.

979
00:50:52,760 --> 00:50:54,860
You can take an embryonic stem cell

980
00:50:54,860 --> 00:50:58,310
that can become any cell, and then instruct it

981
00:50:58,310 --> 00:51:01,740
to specifically almost entirely become

982
00:51:01,740 --> 00:51:04,473
human beating ventricular muscle.

983
00:51:06,290 --> 00:51:08,363
This is an exciting event.

984
00:51:10,360 --> 00:51:12,540
With the same transformative properties

985
00:51:12,540 --> 00:51:15,590
of embryonic stem cells, researchers in Israel

986
00:51:15,590 --> 00:51:20,230
are using iPS cells to develop startling new innovations,

987
00:51:20,230 --> 00:51:22,833
even printing a miniature heart.

988
00:51:24,640 --> 00:51:27,930
This is the first time that the whole cellular heart

989
00:51:27,930 --> 00:51:31,030
with blood vessel is printed.

990
00:51:31,030 --> 00:51:33,200
How did they do it?

991
00:51:33,200 --> 00:51:35,710
Tal Dvir and a team of research scientists

992
00:51:35,710 --> 00:51:39,520
at Tel Aviv University harvested patients' fatty tissue

993
00:51:39,520 --> 00:51:42,030
to produce a personalized biological hydrogel

994
00:51:43,494 --> 00:51:45,610
as well as iPS cells manipulated

995
00:51:45,610 --> 00:51:48,203
to become cardiac and vascular cells.

996
00:51:50,040 --> 00:51:53,210
Together, these form what Dvir calls bioinks.

997
00:51:54,963 --> 00:51:58,229
We have bioinks for the heart and bioinks

998
00:51:58,229 --> 00:52:00,053
for the blood vessels, and then we use

999
00:52:00,053 --> 00:52:02,630
a 3D printer to print whole hearts

1000
00:52:02,630 --> 00:52:04,633
with the major blood vessels.

1001
00:52:06,200 --> 00:52:10,860
The next stage is to mature these hearts in the lab

1002
00:52:10,860 --> 00:52:12,890
for at least a month to help the cells

1003
00:52:12,890 --> 00:52:16,213
or teach them how to interact with each other

1004
00:52:16,213 --> 00:52:18,020
and how to provide electrical signal

1005
00:52:18,020 --> 00:52:20,040
and to have a synchronous contraction

1006
00:52:20,040 --> 00:52:22,510
or pumping ability of the heart.

1007
00:52:22,510 --> 00:52:27,380
And in a year or two we hope to take these hearts

1008
00:52:27,380 --> 00:52:30,050
and transplant them in small animal models,

1009
00:52:30,050 --> 00:52:31,921
in rats or rabbits.

1010
00:52:31,921 --> 00:52:32,754
(tense music)

1011
00:52:32,754 --> 00:52:34,320
Astounding, no doubt,

1012
00:52:34,320 --> 00:52:36,020
and while much more work must be done

1013
00:52:36,020 --> 00:52:39,460
to scale up the study from printing rabbit-sized organs

1014
00:52:39,460 --> 00:52:41,840
to a truly human-sized heart,

1015
00:52:41,840 --> 00:52:44,163
its impact may be more immediate.

1016
00:52:45,170 --> 00:52:50,080
And in a year or two, we hope to take these hearts

1017
00:52:50,080 --> 00:52:52,750
and transplant them in small animal models,

1018
00:52:52,750 --> 00:52:54,103
in rats or rabbits.

1019
00:52:54,940 --> 00:52:56,950
The jury's still out as to whether or not

1020
00:52:56,950 --> 00:52:59,100
we should edit out dangerous genes in a way

1021
00:52:59,100 --> 00:53:00,740
that would eliminate them entirely

1022
00:53:00,740 --> 00:53:05,660
from all future generations, but living a full lifetime

1023
00:53:05,660 --> 00:53:08,230
despite disease or serious injury seems to be

1024
00:53:08,230 --> 00:53:10,320
the inherent goal of most species,

1025
00:53:10,320 --> 00:53:13,423
whether human or animal, present or past.

1026
00:53:14,830 --> 00:53:17,650
By studying both mortal and serious injuries

1027
00:53:17,650 --> 00:53:21,040
on fossil bones, scientists in North and South America

1028
00:53:21,040 --> 00:53:24,700
have redefined the daily lives of one of the most iconic

1029
00:53:24,700 --> 00:53:28,262
prehistoric predators, Smilodon.

1030
00:53:28,262 --> 00:53:30,762
(tense music)

1031
00:53:31,670 --> 00:53:35,983
Saber-toothed cats, it seems, are both fighters and lovers.

1032
00:53:36,940 --> 00:53:39,690
(dramatic music)

1033
00:53:41,830 --> 00:53:43,420
(teeth crunching)

1034
00:53:43,420 --> 00:53:44,778
Forget tigers.

1035
00:53:44,778 --> 00:53:45,780
(cat roars)

1036
00:53:45,780 --> 00:53:48,463
Forget lions and leopards.

1037
00:53:49,790 --> 00:53:51,980
One ferocious feline killed its prey

1038
00:53:51,980 --> 00:53:54,449
with canines nearly a foot long.

1039
00:53:54,449 --> 00:53:55,860
(Smilodon growls)

1040
00:53:55,860 --> 00:53:58,940
But while the beast weighed close to half a ton,

1041
00:53:58,940 --> 00:54:02,610
walked on paws three times larger than a Bengal tiger's,

1042
00:54:02,610 --> 00:54:06,470
Smilodon remains one of the most enigmatic predators,

1043
00:54:06,470 --> 00:54:07,693
past or present.

1044
00:54:08,727 --> 00:54:11,560
(Smilodon growls)

1045
00:54:13,051 --> 00:54:14,320
(man speaking in foreign language)

1046
00:54:14,320 --> 00:54:18,340
Now, scientists are breaking into Smilodon's secret life

1047
00:54:18,340 --> 00:54:20,023
through those incredible fangs.

1048
00:54:22,750 --> 00:54:24,360
So, there's lots of advantages of having

1049
00:54:24,360 --> 00:54:27,490
these elongated sabers, one of which is the ability

1050
00:54:27,490 --> 00:54:30,083
to have your prey bleed out very quickly.

1051
00:54:31,360 --> 00:54:33,080
Dr. Larisa DeSantis

1052
00:54:33,080 --> 00:54:36,613
is a vertebrate paleontologist at Vanderbilt University.

1053
00:54:37,700 --> 00:54:41,550
The saber teeth are actually as long, if not longer,

1054
00:54:41,550 --> 00:54:44,386
than some T-Rex teeth.

1055
00:54:44,386 --> 00:54:46,210
(soft tense music)

1056
00:54:46,210 --> 00:54:48,170
Dr. Nicolas Chimento

1057
00:54:48,170 --> 00:54:51,280
is at the cCmparative Anatomy Lab of Vertebrate Evolution

1058
00:54:51,280 --> 00:54:54,403
in the Natural History Museum Buenos Aires.

1059
00:54:56,141 --> 00:54:57,940
(Nicolas speaking in foreign language)

1060
00:54:57,940 --> 00:54:59,170
This is original material

1061
00:54:59,170 --> 00:55:02,250
from a saber-tooth cat, a Smilodon populator.

1062
00:55:02,250 --> 00:55:05,263
It was found here in Rio Areco in the Pampas region.

1063
00:55:06,437 --> 00:55:07,270
(men speaking in foreign language)

1064
00:55:07,270 --> 00:55:08,980
His new discovery in Argentina

1065
00:55:08,980 --> 00:55:11,760
suggests that Knife Tooth used its canines

1066
00:55:11,760 --> 00:55:14,570
not just to dispatch prey, but to battle

1067
00:55:14,570 --> 00:55:16,263
with members of its own kind.

1068
00:55:18,439 --> 00:55:20,090
(speaking in foreign language)

1069
00:55:20,090 --> 00:55:23,230
Here it had an oval-shaped hole,

1070
00:55:23,230 --> 00:55:25,090
and the shape coincided with the canine

1071
00:55:25,090 --> 00:55:26,323
of a saber-tooth cat.

1072
00:55:28,090 --> 00:55:30,970
So, what we did was insert the canine

1073
00:55:30,970 --> 00:55:33,220
into that hole and it matched the shape

1074
00:55:33,220 --> 00:55:35,363
and fit perfectly inside the skull.

1075
00:55:37,550 --> 00:55:39,370
The punctures in both skulls

1076
00:55:39,370 --> 00:55:42,327
could only have been inflicted by other Smilodons.

1077
00:55:44,880 --> 00:55:45,930
So, this is a wound

1078
00:55:45,930 --> 00:55:49,113
that would have undoubtedly caused the animal to die.

1079
00:55:51,580 --> 00:55:53,620
The Argentine specimen shows a wound

1080
00:55:53,620 --> 00:55:55,603
that appears to be instantly fatal.

1081
00:55:56,820 --> 00:55:59,330
It's a huge discovery as Smilodon fossils

1082
00:55:59,330 --> 00:56:01,433
are relatively rare in South America.

1083
00:56:03,030 --> 00:56:06,050
Smilodon kittens didn't sport true fangs

1084
00:56:06,050 --> 00:56:07,950
until they were about three years old.

1085
00:56:08,830 --> 00:56:12,040
There is a true evolutionary benefit

1086
00:56:12,040 --> 00:56:14,900
to having that tooth come completely in

1087
00:56:14,900 --> 00:56:17,640
before the other tooth, the baby tooth falls out,

1088
00:56:17,640 --> 00:56:20,500
and that provides evidence that these animals

1089
00:56:20,500 --> 00:56:22,480
were potentially provisioned or cared for

1090
00:56:22,480 --> 00:56:25,230
because those teeth were so critical to their survival.

1091
00:56:26,086 --> 00:56:26,919
(suspenseful music)

1092
00:56:26,919 --> 00:56:28,960
Until their weaponry was fully developed,

1093
00:56:28,960 --> 00:56:31,733
Smilodon kittens needed to stick close to mom.

1094
00:56:32,680 --> 00:56:35,050
It was taking a long time for these teeth to develop

1095
00:56:35,050 --> 00:56:37,520
and those were that critical for hunting,

1096
00:56:37,520 --> 00:56:40,740
then there may have been extended period of parental care

1097
00:56:40,740 --> 00:56:43,710
allowing for these animals to become more mature

1098
00:56:43,710 --> 00:56:47,610
and able to hunt effectively on the landscape.

1099
00:56:47,610 --> 00:56:50,070
This suggests that the prehistoric cats

1100
00:56:50,070 --> 00:56:53,683
may have had expanded family structures, similar to wolves.

1101
00:56:57,420 --> 00:57:00,810
We're not sure if saber-toothed cats hunted in pairs

1102
00:57:00,810 --> 00:57:03,713
or in prides, but they worked together.

1103
00:57:07,385 --> 00:57:10,600
(tense music)
(cat growling)

1104
00:57:10,600 --> 00:57:13,500
The prehistoric landscape was rich with forests

1105
00:57:13,500 --> 00:57:15,863
and prairies with many big beasts.

1106
00:57:16,950 --> 00:57:20,510
Giant ground sloths, short-faced bears,

1107
00:57:20,510 --> 00:57:24,260
mammoths and mastodons, and camel-like creatures

1108
00:57:24,260 --> 00:57:26,203
lived side-by-side with Smilodon.

1109
00:57:27,900 --> 00:57:30,550
Saber-toothed cats were the apex predators

1110
00:57:30,550 --> 00:57:32,173
throughout Pleistocene America.

1111
00:57:34,040 --> 00:57:36,180
Still, hunting could be dangerous

1112
00:57:36,180 --> 00:57:39,130
and injury could mean starvation for the predator.

1113
00:57:42,170 --> 00:57:44,130
We can actually analyze the teeth

1114
00:57:44,130 --> 00:57:46,480
of fossil animals and get an understanding

1115
00:57:46,480 --> 00:57:47,730
of what they were eating.

1116
00:57:49,240 --> 00:57:51,110
By analyzing the chemical signature

1117
00:57:51,110 --> 00:57:54,840
of a Smilodon's tooth enamel, she can see what it preyed on

1118
00:57:54,840 --> 00:57:57,820
and where that prey lived, and by studying

1119
00:57:57,820 --> 00:58:00,510
the microscopic grooves and wear on the surface

1120
00:58:00,510 --> 00:58:02,960
of the teeth, she can tell whether the owner

1121
00:58:02,960 --> 00:58:06,593
crunched bone or dined on delicacies.

1122
00:58:07,860 --> 00:58:09,900
And what we actually found was pretty interesting,

1123
00:58:09,900 --> 00:58:12,450
is that the individuals that were injured

1124
00:58:12,450 --> 00:58:14,710
were actually eating softer foods,

1125
00:58:14,710 --> 00:58:17,930
and this suggests that potentially they were actually

1126
00:58:17,930 --> 00:58:19,310
being provisioned food.

1127
00:58:19,310 --> 00:58:21,540
So, these weren't animals that were sort of

1128
00:58:21,540 --> 00:58:23,760
just desperately scavenging

1129
00:58:23,760 --> 00:58:25,300
for whatever food they could find.

1130
00:58:25,300 --> 00:58:30,170
They were actually able to get access to the flesh, likely,

1131
00:58:30,170 --> 00:58:31,840
and then potentially by other cats.

1132
00:58:31,840 --> 00:58:34,943
And so, that was really, really an exciting find.

1133
00:58:36,670 --> 00:58:39,390
And that is quite remarkable because that suggests

1134
00:58:39,390 --> 00:58:41,410
that these animals were really, ya know,

1135
00:58:41,410 --> 00:58:42,631
caring for each other.

1136
00:58:42,631 --> 00:58:43,490
(suspenseful music)

1137
00:58:43,490 --> 00:58:44,960
Growing those saber teeth

1138
00:58:44,960 --> 00:58:47,310
was a feat of evolutionary engineering

1139
00:58:47,310 --> 00:58:50,620
that continues to fascinate everyone who lays eyes on them.

1140
00:58:53,103 --> 00:58:54,590
(tense music)

1141
00:58:54,590 --> 00:58:58,420
Four little foot bones found by accident in 1994,

1142
00:58:58,420 --> 00:59:00,780
have led South African scientists to discover

1143
00:59:00,780 --> 00:59:04,563
the most complete paleoanthropological find of is kind.

1144
00:59:06,000 --> 00:59:10,580
Since revealed, fossil by fossil over 20 years,

1145
00:59:10,580 --> 00:59:13,300
the new discovery replaces much guess work

1146
00:59:13,300 --> 00:59:16,293
with real answers about our early ancestors.

1147
00:59:17,733 --> 00:59:19,930
(ominous music)

1148
00:59:19,930 --> 00:59:23,930
She was an older woman, not much over four feet,

1149
00:59:23,930 --> 00:59:25,800
and perhaps in her foraging,

1150
00:59:25,800 --> 00:59:28,170
she'd been disturbed by something,

1151
00:59:28,170 --> 00:59:31,970
some predator, a saber-tooth or a lion,

1152
00:59:31,970 --> 00:59:34,143
and had hastily tried to get away.

1153
00:59:35,880 --> 00:59:39,383
She fell into a cave, now known as the Sterkfontein,

1154
00:59:40,364 --> 00:59:41,620
and the four little foot bones of hers

1155
00:59:41,620 --> 00:59:44,330
were discovered here quite by accident

1156
00:59:44,330 --> 00:59:46,563
3.7 million years later.

1157
00:59:48,070 --> 00:59:51,210
Usually, scientists only discover small fragments

1158
00:59:51,210 --> 00:59:54,400
of a skeleton in the deep bedrock of time.

1159
00:59:54,400 --> 00:59:57,280
These give them clues, but not many answers

1160
00:59:57,280 --> 00:59:58,583
about our ancestors.

1161
00:59:59,580 --> 01:00:02,195
That has all changed with Little Foot.

1162
01:00:02,195 --> 01:00:03,100
(bright music)

1163
01:00:03,100 --> 01:00:06,230
I could see a little white bone that I recognized

1164
01:00:06,230 --> 01:00:09,870
as a foot bone of a hominid, and then another one,

1165
01:00:12,381 --> 01:00:14,930
(chuckles) and then another one.

1166
01:00:14,930 --> 01:00:17,503
I also found part of a tibia,

1167
01:00:18,390 --> 01:00:20,980
and I found part of a fibula.

1168
01:00:20,980 --> 01:00:25,140
So, I had parts of the foot and lower legs

1169
01:00:25,140 --> 01:00:26,687
from left and right.

1170
01:00:27,580 --> 01:00:30,040
From these first little foot fragments,

1171
01:00:30,040 --> 01:00:34,670
the team, Ron Clarke, Stephen Motsumi, and Nkwane Molefe

1172
01:00:34,670 --> 01:00:38,140
set out to find and piece together the rest.

1173
01:00:38,140 --> 01:00:41,053
It was to be a labor of love over decades.

1174
01:00:43,080 --> 01:00:46,950
Their biggest challenge was to remove soft fossil bone

1175
01:00:46,950 --> 01:00:50,560
from breccia, a type of natural concrete,

1176
01:00:50,560 --> 01:00:53,413
while keeping every single fossil fragment undamaged.

1177
01:00:56,000 --> 01:00:58,160
These are the actual fossils,

1178
01:00:58,160 --> 01:01:02,053
all assembled from one individual who fell into a cave

1179
01:01:02,053 --> 01:01:06,480
3.7 million years ago and left us a legacy

1180
01:01:06,480 --> 01:01:09,760
of knowledge beyond measure, including the only

1181
01:01:09,760 --> 01:01:14,603
complete skull and complete dentition, Little Foot.

1182
01:01:16,410 --> 01:01:21,410
This was the first time ever that a complete adult skull

1183
01:01:22,370 --> 01:01:25,111
of an Australopithecus had been found.

1184
01:01:25,111 --> 01:01:26,170
(tense music)

1185
01:01:26,170 --> 01:01:30,180
It had arms that were like ours, relatively short,

1186
01:01:30,180 --> 01:01:34,230
and I could see that the legs were actually longer

1187
01:01:34,230 --> 01:01:37,110
than the arms, just like us.

1188
01:01:37,110 --> 01:01:42,110
This human ancestor had proportions similar to us.

1189
01:01:43,340 --> 01:01:45,910
The fossils which Little Foot has offered up

1190
01:01:45,910 --> 01:01:48,100
quite literally fill the missing gaps

1191
01:01:48,100 --> 01:01:50,703
in our understanding of our early ancestors.

1192
01:01:52,320 --> 01:01:55,763
Little Foot, or Australopithecus Prometheus,

1193
01:01:56,850 --> 01:01:59,580
stood upright and has waited a long time

1194
01:01:59,580 --> 01:02:02,550
to pass on her secrets, and there's no doubt

1195
01:02:02,550 --> 01:02:04,873
she'll give us more answers in time to come.

1196
01:02:07,170 --> 01:02:10,100
And now, archaeologists may have finally figured out

1197
01:02:10,100 --> 01:02:11,683
how the pyramids were built.

1198
01:02:12,800 --> 01:02:14,470
At the ancient quarry of Hatnub,

1199
01:02:14,470 --> 01:02:17,010
they unearthed a contraption that would've been used

1200
01:02:17,010 --> 01:02:19,610
to transport heavy alabaster stones

1201
01:02:19,610 --> 01:02:23,809
up a very steep ramp 4500 years ago.

1202
01:02:23,809 --> 01:02:26,850
(mysterious music)

1203
01:02:26,850 --> 01:02:29,020
At the foot of the Pyramid of Khufu,

1204
01:02:29,020 --> 01:02:32,100
we can still see the quarries from which the majority,

1205
01:02:32,100 --> 01:02:35,363
that's about 95% of the blocks, were extracted.

1206
01:02:36,760 --> 01:02:39,320
By building the pyramids, the Ancient Egyptians

1207
01:02:39,320 --> 01:02:42,560
transformed the landscape, changing the geography

1208
01:02:42,560 --> 01:02:43,403
of the place.

1209
01:02:44,620 --> 01:02:47,160
They literally tore off much of the rocky base

1210
01:02:47,160 --> 01:02:48,423
of the Giza Plateau.

1211
01:02:49,510 --> 01:02:51,210
The Sphinx itself is a remnant

1212
01:02:51,210 --> 01:02:53,720
of this hard limestone plateau,

1213
01:02:53,720 --> 01:02:55,650
and with all the gravel and excess stone

1214
01:02:55,650 --> 01:02:58,500
this method produced, would have been reused

1215
01:02:58,500 --> 01:02:59,663
to build the ramps.

1216
01:03:03,290 --> 01:03:06,640
But what type of ramp did they use 4500 years ago

1217
01:03:06,640 --> 01:03:10,283
to transport blocks to a height of 146 meters?

1218
01:03:11,610 --> 01:03:15,180
The debate is raging between Egyptologyists and specialists

1219
01:03:15,180 --> 01:03:17,053
and many models have been proposed.

1220
01:03:18,520 --> 01:03:21,300
A single ramp is either too steep or too long

1221
01:03:21,300 --> 01:03:25,560
to maintain a realistic slope of no more than 12%.

1222
01:03:25,560 --> 01:03:26,610
(suspenseful music)

1223
01:03:26,610 --> 01:03:29,610
Several ramps seem to be a very costly solution

1224
01:03:29,610 --> 01:03:31,353
in terms of time and effort.

1225
01:03:32,920 --> 01:03:36,050
Is it an external rap around ramp?

1226
01:03:36,050 --> 01:03:38,100
Or the kind of internal ramp proposed

1227
01:03:38,100 --> 01:03:41,823
by architect Jean-Pierre Houdin in the 2000s?

1228
01:03:45,690 --> 01:03:47,720
For now, there's no definitive evidence

1229
01:03:47,720 --> 01:03:50,040
that would settle this debate.

1230
01:03:50,040 --> 01:03:52,620
Again, it may be necessary to distance ourselves

1231
01:03:52,620 --> 01:03:54,793
from the pyramids to find some answers.

1232
01:03:55,760 --> 01:03:59,070
300 kilometers south of the Giza pyramids,

1233
01:03:59,070 --> 01:04:01,280
a Franco-British archaeological mission

1234
01:04:01,280 --> 01:04:03,830
with the help of 100 Egyptian workers

1235
01:04:03,830 --> 01:04:06,263
is possibly about to make a major discovery.

1236
01:04:22,310 --> 01:04:24,330
In no other quarry have these type

1237
01:04:24,330 --> 01:04:25,603
of elements been found.

1238
01:04:26,830 --> 01:04:31,830
A ramp at a 20 to 25% grade, and in some places even more

1239
01:04:32,630 --> 01:04:36,360
depending on the location, and on the sides

1240
01:04:36,360 --> 01:04:40,033
there are stairs with holes cut into the rock.

1241
01:04:41,690 --> 01:04:43,413
What were these holes used for?

1242
01:04:44,420 --> 01:04:45,793
How did this ramp work?

1243
01:04:47,000 --> 01:04:49,370
Can it provide new clues about the construction

1244
01:04:49,370 --> 01:04:52,453
of the pyramids and the ramp system used at the time?

1245
01:04:54,230 --> 01:04:57,220
Olivier Lavigne has analyzed all these clues

1246
01:04:57,220 --> 01:04:59,371
and developed a hypothesis.

1247
01:04:59,371 --> 01:05:02,371
(suspenseful music)

1248
01:06:01,230 --> 01:06:04,090
They would have used mud, silt from the Nile,

1249
01:06:04,090 --> 01:06:06,550
to lubricate the ramp and slide the block,

1250
01:06:06,550 --> 01:06:08,913
eliminating friction as much as possible.

1251
01:06:09,820 --> 01:06:13,600
Here, along the towpath, large alabaster stones,

1252
01:06:13,600 --> 01:06:16,070
possibly weighing as much as 58 tons

1253
01:06:16,070 --> 01:06:17,463
could be moved this way.

1254
01:06:20,010 --> 01:06:22,570
So, as the block advanced, the teams above

1255
01:06:22,570 --> 01:06:24,810
would have positioned the ropes ahead of time

1256
01:06:24,810 --> 01:06:27,320
on the next set of poles so that the block

1257
01:06:27,320 --> 01:06:30,679
would have moved forward as smoothly as possible.

1258
01:06:30,679 --> 01:06:33,679
(suspenseful music)

1259
01:06:40,710 --> 01:06:43,730
According to Olivier Lavigne, this ramp system

1260
01:06:43,730 --> 01:06:46,130
could have been adapted to the Pyramid of Khufu.

1261
01:06:50,900 --> 01:06:53,850
But ramps on the pyramid were not built out of rock.

1262
01:06:53,850 --> 01:06:57,403
Instead, they were constructed with gravel and bricks.

1263
01:07:02,210 --> 01:07:06,080
So, to secure and stabilize the space between the poles,

1264
01:07:06,080 --> 01:07:09,060
they used wooden crossbars inside the ramp

1265
01:07:09,060 --> 01:07:10,363
and also above it.

1266
01:07:12,000 --> 01:07:13,763
But is this system feasible?

1267
01:07:15,640 --> 01:07:17,580
This hypothesis needs to be tested

1268
01:07:17,580 --> 01:07:19,593
under real conditions to know for sure.

1269
01:07:23,009 --> 01:07:25,509
(tense music)