1 00:00:16,800 --> 00:00:20,400 (wind) 2 00:00:22,734 --> 00:00:25,233 SAGAN: We were hunters and foragers. 3 00:00:26,000 --> 00:00:28,800 The frontier was everywhere. 4 00:00:37,100 --> 00:00:42,000 We were bounded only by the earth and the ocean and the sky. 5 00:00:49,533 --> 00:00:54,133 The open road still softly calls like a nearly forgotten 6 00:00:54,266 --> 00:00:56,266 song of childhood. 7 00:00:57,233 --> 00:01:00,667 For all our failings, despite our limitations and 8 00:01:00,800 --> 00:01:04,767 fallibilities, we humans are capable of greatness. 9 00:01:10,567 --> 00:01:14,533 How far will our nomadic species have wandered by the 10 00:01:14,667 --> 00:01:17,200 end of the next century? 11 00:01:19,000 --> 00:01:21,800 And the next millennium? 12 00:01:41,233 --> 00:01:47,467 ♪ ♪ 13 00:01:49,033 --> 00:01:52,734 TYSON: Welcome back to the shores of the cosmic ocean... 14 00:01:53,100 --> 00:01:55,066 An immensity of space and time, 15 00:01:56,233 --> 00:01:58,700 a vastness still mostly uncharted. 16 00:01:59,500 --> 00:02:03,200 We're bound for the possible worlds revealed by science. 17 00:02:03,967 --> 00:02:07,400 We'll take a ride on the underground worldwide network 18 00:02:07,533 --> 00:02:09,266 that no one knew was there. 19 00:02:10,200 --> 00:02:13,333 I'm going to tell you a first contact story that's true. 20 00:02:16,333 --> 00:02:19,200 We'll meet some of the most courageous people who ever lived. 21 00:02:20,500 --> 00:02:25,367 And we're going to venture into the future we can still have, 22 00:02:25,900 --> 00:02:30,233 to the homes of our distant descendants among the starts. 23 00:02:31,000 --> 00:02:34,100 Science can carry us across that vastness. 24 00:02:34,233 --> 00:02:36,900 But without imagination, we go nowhere. 25 00:02:39,133 --> 00:02:42,533 Our Ship of the Imagination is propelled by twin engines 26 00:02:42,667 --> 00:02:44,867 of skepticism and wonder. 27 00:02:45,533 --> 00:02:49,667 It's guided by the simple set of rules that define science 28 00:02:49,800 --> 00:02:51,133 and make it so powerful. 29 00:02:52,800 --> 00:02:54,233 (splash) 30 00:02:54,800 --> 00:02:57,834 Test ideas by experiment and observation. 31 00:02:57,967 --> 00:03:00,567 Build on those ideas that pass the test. 32 00:03:01,266 --> 00:03:03,367 Reject the ones that fail. 33 00:03:03,500 --> 00:03:06,333 Follow the evidence wherever it leads. 34 00:03:06,467 --> 00:03:08,600 and question everything. 35 00:03:09,400 --> 00:03:13,800 Take these rules to heart, and the cosmos is yours. 36 00:03:14,800 --> 00:03:17,000 Come with me... 37 00:03:24,767 --> 00:03:30,567 (theme music plays). 38 00:03:50,033 --> 00:03:55,800 ♪ ♪ 39 00:04:14,967 --> 00:04:21,333 ♪ ♪ 40 00:04:40,700 --> 00:04:46,567 ♪ ♪ 41 00:04:48,633 --> 00:04:51,500 TYSON: Our Ship of the Imagination can take us 42 00:04:51,633 --> 00:04:54,567 anywhere in space and time. 43 00:04:56,033 --> 00:04:59,133 The cosmos is right outside our front window. 44 00:05:00,333 --> 00:05:03,600 If you want to see the past, look down. 45 00:05:16,333 --> 00:05:19,400 And if you want to see the future, look up. 46 00:05:33,066 --> 00:05:36,900 On this voyage, we are bound for a distant galaxy. 47 00:05:38,967 --> 00:05:42,467 And we'll discover how we as a species became 48 00:05:42,600 --> 00:05:44,800 explorers of the cosmos. 49 00:05:45,600 --> 00:05:47,934 There. There she is. 50 00:05:48,066 --> 00:05:50,200 NASA's Voyager 1. 51 00:05:50,333 --> 00:05:52,567 Launched in 1977, 52 00:05:52,700 --> 00:05:55,467 she is the most distant object built by human hands. 53 00:05:56,867 --> 00:05:59,367 She's done some hard traveling since our last encounter, 54 00:06:00,033 --> 00:06:02,333 logged another billion and a half miles. 55 00:06:02,934 --> 00:06:06,266 Voyager's making for other parts of our Milky Way, 56 00:06:06,400 --> 00:06:09,700 but we have another, far more distant destination. 57 00:06:10,934 --> 00:06:14,166 The cosmic ocean is made of space and time. 58 00:06:14,967 --> 00:06:18,000 You can't move in space without also moving in time. 59 00:06:18,800 --> 00:06:21,834 Our voyage will take us a long way from home, 60 00:06:22,166 --> 00:06:25,233 a little more than a billion light-years. 61 00:06:25,367 --> 00:06:28,867 We're also traveling a billion years into the past, 62 00:06:29,000 --> 00:06:32,333 to an event so violent it will even shatter time. 63 00:06:43,834 --> 00:06:46,266 Now, we're getting close to our destination. 64 00:06:46,400 --> 00:06:48,700 This is what we came for. 65 00:06:51,800 --> 00:06:54,467 These two black holes were born from the collapse of a 66 00:06:54,600 --> 00:06:57,400 pair of massive stars. 67 00:06:58,066 --> 00:07:00,567 And they've been doing a gravitational tango ever since 68 00:07:00,967 --> 00:07:02,667 for millions of years. 69 00:07:02,800 --> 00:07:05,200 We're here for the climax. 70 00:07:05,467 --> 00:07:08,300 When those two collide, they will set off a space-time 71 00:07:08,433 --> 00:07:10,800 tsunami that will stretch and compress space 72 00:07:10,934 --> 00:07:12,467 in all directions. 73 00:07:12,600 --> 00:07:15,233 And it will slow down time itself, 74 00:07:15,367 --> 00:07:17,934 before speeding it up and slowing it down again. 75 00:07:24,400 --> 00:07:28,533 (distorted, echoes). 76 00:07:44,700 --> 00:07:47,900 Gravitational... 77 00:07:48,433 --> 00:07:51,300 and it will slow down time itself... 78 00:07:52,867 --> 00:07:55,967 Set off a space-time tsunami... 79 00:07:56,300 --> 00:07:59,333 Stretch and compress space in all directions a billion 80 00:07:59,467 --> 00:08:01,266 light-years away. 81 00:08:04,266 --> 00:08:07,633 (grunts and exhales). 82 00:08:09,900 --> 00:08:11,667 What does an event that took place more than a billion 83 00:08:11,800 --> 00:08:14,967 light-years away have to do with us? 84 00:08:15,467 --> 00:08:18,333 Albert Einstein was the first to understand that matter 85 00:08:18,467 --> 00:08:21,133 could send ripples across space-time. 86 00:08:21,500 --> 00:08:24,033 He imagined that catastrophic explosions of matter should 87 00:08:24,166 --> 00:08:27,500 create something much bigger than ripples, great waves, 88 00:08:28,500 --> 00:08:30,533 gravitational waves. 89 00:08:30,667 --> 00:08:33,500 You are seeing and hearing me right now, 90 00:08:33,633 --> 00:08:36,867 on whatever device you have, because we figured out a way 91 00:08:37,000 --> 00:08:39,967 to manipulate the electromagnetic spectrum. 92 00:08:40,300 --> 00:08:42,667 If we can learn to surf those gravitational waves the 93 00:08:42,800 --> 00:08:45,800 way we know how to ride the electromagnetic ones, 94 00:08:45,934 --> 00:08:47,533 who knows? 95 00:08:47,667 --> 00:08:50,867 It's as impossible to foresee as our world was to the 96 00:08:51,066 --> 00:08:53,467 scientists who experimented with electricity back 97 00:08:53,600 --> 00:08:56,100 in the 19th century. 98 00:08:56,233 --> 00:08:59,100 Cosmologists predicted the existence of black holes. 99 00:09:00,200 --> 00:09:03,567 Gravitational waves are the first direct evidence that 100 00:09:03,700 --> 00:09:05,900 black holes are real. 101 00:09:06,033 --> 00:09:08,467 But they may also provide a new way of knowing and 102 00:09:08,600 --> 00:09:10,300 exploring the cosmos. 103 00:09:10,433 --> 00:09:12,934 We can add it to the other senses that science has 104 00:09:13,066 --> 00:09:16,600 devised to penetrate the great dark ocean, 105 00:09:16,734 --> 00:09:19,667 all the kinds of light we use; gamma ray, 106 00:09:22,600 --> 00:09:26,066 X-ray, ultraviolet, 107 00:09:27,800 --> 00:09:31,200 infrared, microwave, 108 00:09:32,700 --> 00:09:36,900 radio wave and visible light. 109 00:09:38,533 --> 00:09:41,667 This newest way to search the cosmos could help us to one 110 00:09:41,800 --> 00:09:45,233 day know what's happening inside those black holes, 111 00:09:46,333 --> 00:09:48,533 and the other hidden places that make up most 112 00:09:48,667 --> 00:09:50,633 of the universe. 113 00:09:50,767 --> 00:09:53,734 What if we could detect the gravitational waves that were 114 00:09:53,867 --> 00:09:56,166 caused by the first moment of creation, 115 00:09:57,400 --> 00:09:59,734 the birth of the cosmos? 116 00:10:01,600 --> 00:10:05,233 What if we could extend our vision to see the whole sweep 117 00:10:05,367 --> 00:10:08,667 of 14 billion years of cosmic evolution? 118 00:10:21,633 --> 00:10:24,233 So, how did we get so smart? 119 00:10:25,533 --> 00:10:28,600 We know something about the evolution of our species, 120 00:10:28,734 --> 00:10:31,367 but how did the human mind evolve? 121 00:10:32,567 --> 00:10:35,467 Where did that crazy ambition to climb the ladder to the 122 00:10:35,600 --> 00:10:37,333 stars come from? 123 00:10:38,100 --> 00:10:42,633 How did we become a way for the universe to know itself? 124 00:10:44,800 --> 00:10:47,633 It started over there. 125 00:10:53,867 --> 00:10:56,633 is a way for us to grasp theCr 126 00:10:56,767 --> 00:10:58,767 vastness of time. 127 00:10:58,900 --> 00:11:00,500 We've taken all of time, 128 00:11:00,633 --> 00:11:03,100 from the birth of the universe to this very moment, 129 00:11:03,233 --> 00:11:06,233 and compressed it into a single calendar year. 130 00:11:06,367 --> 00:11:08,767 On this scale, every month represents a little 131 00:11:08,900 --> 00:11:10,967 more than a billion years. 132 00:11:11,100 --> 00:11:14,400 Every day represents nearly 40 million years. 133 00:11:16,133 --> 00:11:19,033 Our own story begins with all the other life on 134 00:11:19,166 --> 00:11:21,333 our little world. 135 00:11:21,467 --> 00:11:24,433 Every living thing on Earth is descended from 136 00:11:24,567 --> 00:11:26,467 a single origin. 137 00:11:26,600 --> 00:11:30,400 It happened in the deep ocean darkness on September 15, 138 00:11:30,533 --> 00:11:33,567 about four billion years ago. 139 00:11:34,567 --> 00:11:38,900 Within this tiny single-celled organism was a kind of chemical ladder, 140 00:11:40,033 --> 00:11:42,433 the DNA double helix. 141 00:11:44,467 --> 00:11:46,867 Star stuff... 142 00:11:47,233 --> 00:11:50,166 Oxygen, carbon, nitrogen... 143 00:11:50,300 --> 00:11:53,333 Elements cooked in the hearts of distant stars, 144 00:11:53,467 --> 00:11:56,834 combined with hydrogen from the Big Bang to become alive 145 00:11:56,967 --> 00:11:59,233 on this little world. 146 00:11:59,533 --> 00:12:02,934 Through random changes, mutations in the genes, 147 00:12:03,066 --> 00:12:05,700 some of which led to more successful life-forms, 148 00:12:05,834 --> 00:12:08,333 what we call evolution by natural selection. 149 00:12:09,166 --> 00:12:13,834 The ladder grew, adding more and more rungs. 150 00:12:15,433 --> 00:12:18,967 It took another three billion years for life to evolve the 151 00:12:19,100 --> 00:12:22,333 complexity of the plants and animals that you could see 152 00:12:22,467 --> 00:12:24,633 with the naked eye. 153 00:12:30,834 --> 00:12:33,567 If the Cosmic Calendar had holidays, 154 00:12:33,700 --> 00:12:36,600 surely December 26 would be one of them. 155 00:12:37,233 --> 00:12:40,467 Some time on this day, about 200 million years ago, 156 00:12:41,867 --> 00:12:44,166 the first mammals evolved. 157 00:12:44,533 --> 00:12:46,867 They brought a new feature to life on Earth: 158 00:12:47,000 --> 00:12:49,467 the neocortex. 159 00:12:50,567 --> 00:12:52,166 Back in the Triassic, 160 00:12:52,300 --> 00:12:55,834 the odds were against her kind, but the dinosaurs that 161 00:12:55,967 --> 00:12:58,800 terrorized the mammals went extinct. 162 00:12:59,934 --> 00:13:02,900 It was the evolution of the neocortex in small, 163 00:13:03,033 --> 00:13:05,033 furtive creatures such as this one, 164 00:13:05,567 --> 00:13:09,233 that enabled their descendants to take over the planet. 165 00:13:09,800 --> 00:13:13,033 Mammals brought something else that was new. 166 00:13:13,333 --> 00:13:15,066 They suckled their young. 167 00:13:15,900 --> 00:13:17,800 They nurtured them. 168 00:13:17,934 --> 00:13:20,233 And there was love. 169 00:13:21,667 --> 00:13:24,867 Mother's Day on the Cosmic Calendar. 170 00:13:28,100 --> 00:13:31,600 Evolution by natural selection means that those living things 171 00:13:31,734 --> 00:13:34,834 able to better adapt to their environment are more likely to 172 00:13:34,967 --> 00:13:37,333 survive and leave offspring. 173 00:13:38,066 --> 00:13:41,700 Intelligence can be a huge selective advantage. 174 00:13:42,066 --> 00:13:45,867 The fate of this planet was changed forever by an event 175 00:13:46,000 --> 00:13:48,500 involving just 13 atoms. 176 00:13:48,800 --> 00:13:51,133 How small is 13 atoms? 177 00:13:51,266 --> 00:13:54,934 It's a quadrillionth the size of a grain of salt. 178 00:13:55,600 --> 00:13:59,467 A mutation occurred in the DNA of just one of our ancestors. 179 00:14:00,266 --> 00:14:03,967 Every source of self-esteem, everything we've learned, 180 00:14:04,100 --> 00:14:07,734 and built, might come down to nothing more than this. 181 00:14:09,600 --> 00:14:11,734 One base pair of a single gene. 182 00:14:12,767 --> 00:14:17,000 Just a single rung programmed the neocortex to grow larger 183 00:14:17,133 --> 00:14:19,133 still and fold more deeply. 184 00:14:19,934 --> 00:14:22,567 Maybe it was a random zap from a cosmic ray, 185 00:14:23,100 --> 00:14:26,200 or a simple error in transmission from one cell to another. 186 00:14:28,000 --> 00:14:31,800 Whatever it was, it led to a change in our species that 187 00:14:31,934 --> 00:14:34,467 would ultimately affect every other species 188 00:14:34,600 --> 00:14:37,133 of life on Earth. 189 00:14:37,800 --> 00:14:40,600 It happened late on New Year's Eve on this 190 00:14:40,734 --> 00:14:43,800 Cosmic Calendar of ours. 191 00:14:48,600 --> 00:14:51,066 To think that, for good or evil, 192 00:14:51,200 --> 00:14:54,400 our ability to feel loyalty and concern for increasingly 193 00:14:54,533 --> 00:14:58,033 larger groups, our obsession with certain belief systems, 194 00:14:58,700 --> 00:15:01,266 our capacity to imagine the future, 195 00:15:01,400 --> 00:15:05,533 our power to transform the world and to search the cosmos 196 00:15:05,667 --> 00:15:08,000 for answers... 197 00:15:08,333 --> 00:15:11,233 The very name we gave to our own species, 198 00:15:11,367 --> 00:15:15,567 homo sapiens, Latin for "wise persons" all of it 199 00:15:15,700 --> 00:15:20,200 comes down to nothing more than a single rung on our tiny 200 00:15:20,333 --> 00:15:22,500 DNA ladder to the stars. 201 00:15:26,133 --> 00:15:28,800 For much of the last hour on the Cosmic Calendar, 202 00:15:29,400 --> 00:15:31,700 for all but the last minute, 203 00:15:31,834 --> 00:15:34,200 our ancestors were hunters and gatherers, 204 00:15:35,700 --> 00:15:38,533 living in small bands. 205 00:15:44,867 --> 00:15:47,533 You know, when people just shrug and say 206 00:15:47,667 --> 00:15:50,867 "chalk it up to human nature," it puzzles me. 207 00:15:51,967 --> 00:15:54,033 They're usually talking about our greed, 208 00:15:54,166 --> 00:15:56,967 our arrogance, our violence. 209 00:15:57,100 --> 00:15:58,667 But we've been human for at least a couple of 210 00:15:58,800 --> 00:16:00,700 hundred thousand years. 211 00:16:00,834 --> 00:16:03,934 For most of that time we weren't that way at all. 212 00:16:04,800 --> 00:16:06,433 How do we know? 213 00:16:06,567 --> 00:16:09,133 From the accounts of explorers and anthropologists 214 00:16:09,266 --> 00:16:11,934 encountering surviving hunter-gatherer societies 215 00:16:12,066 --> 00:16:14,867 across four centuries. 216 00:16:15,000 --> 00:16:17,500 There are, of course, exceptions, especially in 217 00:16:17,633 --> 00:16:20,233 the circumstances of extreme scarcity. 218 00:16:20,367 --> 00:16:24,066 But the overwhelming consensus paints a picture of humans 219 00:16:24,200 --> 00:16:26,467 who lived in relative harmony with each other 220 00:16:26,600 --> 00:16:28,500 and the environment. 221 00:16:28,633 --> 00:16:31,500 We shared the little we had because we knew that our 222 00:16:31,633 --> 00:16:34,033 survival depended on the group. 223 00:16:34,600 --> 00:16:38,066 We didn't prize wealth beyond our needs because possessions 224 00:16:38,200 --> 00:16:40,233 would just weigh us down as we wandered. 225 00:16:41,233 --> 00:16:44,233 We were different from our non-human primate ancestors 226 00:16:44,367 --> 00:16:47,500 with their alpha-males bullying their way to dominance. 227 00:16:56,734 --> 00:16:59,300 And where was God? 228 00:17:01,233 --> 00:17:03,066 Everywhere. 229 00:17:03,200 --> 00:17:04,934 In the rocks and in the rivers, 230 00:17:05,066 --> 00:17:09,133 in the trees, in the birds and every living thing. 231 00:17:09,433 --> 00:17:11,400 And that was human nature for a couple of 232 00:17:11,533 --> 00:17:13,967 hundred thousand years. 233 00:17:14,400 --> 00:17:17,567 I'm standing on the southern tip of Africa and imagining 234 00:17:17,700 --> 00:17:19,967 what it was like some time in the last hundreds 235 00:17:20,100 --> 00:17:21,800 of thousands of years. 236 00:17:21,934 --> 00:17:26,166 Back then, Africa was home to all the world's homo sapiens... 237 00:17:27,433 --> 00:17:29,767 All 10,000 of them. 238 00:17:30,233 --> 00:17:33,200 If you were an extra-terrestrial on a survey mission, 239 00:17:33,333 --> 00:17:36,834 you might have thought we were an endangered species. 240 00:17:36,967 --> 00:17:40,867 Someday soon there will be ten billion of us. 241 00:17:41,000 --> 00:17:42,333 What happened? 242 00:17:42,467 --> 00:17:44,667 How did we become the globe-girdling, 243 00:17:44,800 --> 00:17:47,767 space-traveling species that we are today? 244 00:17:56,834 --> 00:18:00,300 Welcome to the first laboratory on Earth. 245 00:18:00,433 --> 00:18:03,300 We're in Blombos Cave where the evolution of the mind 246 00:18:03,433 --> 00:18:05,300 made a great leap. 247 00:18:05,433 --> 00:18:07,767 Our ancestors were conducting chemistry experiments 248 00:18:07,900 --> 00:18:11,867 here with a mineral rich in iron, ocher. 249 00:18:13,400 --> 00:18:16,533 They used it to decorate objects with bits of red color, 250 00:18:16,667 --> 00:18:19,100 but it may have also had other uses, 251 00:18:19,233 --> 00:18:21,033 to preserve animal hides or as a medicine, 252 00:18:22,200 --> 00:18:24,100 or as a way to sharpen their tools, 253 00:18:25,867 --> 00:18:28,333 or maybe as an insect repellent. 254 00:18:29,834 --> 00:18:32,100 And they engraved the ocher with symbols. 255 00:18:32,233 --> 00:18:36,000 Something completely new on the planet Earth, art. 256 00:18:37,633 --> 00:18:39,467 Not to be eaten. 257 00:18:39,600 --> 00:18:41,333 Not to provide shelter. 258 00:18:41,467 --> 00:18:44,066 But to symbolize something... 259 00:18:44,200 --> 00:18:46,367 Or just to be. 260 00:18:47,400 --> 00:18:48,900 It looks a little bit like a ladder, 261 00:18:49,033 --> 00:18:50,533 or a double helix. 262 00:18:50,667 --> 00:18:52,333 Whatever it was supposed to be, 263 00:18:52,467 --> 00:18:55,600 it's the earliest remnant we have of human culture. 264 00:18:56,000 --> 00:19:00,367 We had found a way to leave behind something distinctly human. 265 00:19:00,734 --> 00:19:04,133 A means to communicate, however enigmatically, 266 00:19:04,266 --> 00:19:08,600 to you and me 100,000 years away. 267 00:19:09,667 --> 00:19:12,633 A great power was discovered here in Blombos Cave. 268 00:19:20,433 --> 00:19:23,800 At 25 cosmic seconds-to-midnight, 269 00:19:23,934 --> 00:19:27,266 between 10,000 and 12,000 years ago, 270 00:19:28,000 --> 00:19:31,834 humans discovered another great power. 271 00:19:32,567 --> 00:19:35,000 Instead of foraging for food, 272 00:19:35,133 --> 00:19:37,734 we learned how to grow it in the earth. 273 00:19:39,133 --> 00:19:42,400 This changed everything. 274 00:19:42,834 --> 00:19:44,767 Our ancestors did something else they had 275 00:19:44,900 --> 00:19:46,633 never done before. 276 00:19:46,767 --> 00:19:49,166 They invented new tools, technology, 277 00:19:50,300 --> 00:19:53,333 to plant and pull food out of the earth. 278 00:19:54,033 --> 00:19:57,100 They settled down and moved indoors. 279 00:19:57,667 --> 00:20:00,600 Our relationship to nature, and to one another, 280 00:20:00,734 --> 00:20:03,300 would never be the same. 281 00:20:03,767 --> 00:20:06,166 This agricultural revolution, 282 00:20:06,300 --> 00:20:09,133 the domestication of plants and animals, 283 00:20:09,266 --> 00:20:12,433 is the mother of all revolutions because all 284 00:20:12,567 --> 00:20:14,834 others trace back to it. 285 00:20:14,967 --> 00:20:17,367 Its consequences reach far beyond even our 286 00:20:17,500 --> 00:20:19,834 own moment in time. 287 00:20:19,967 --> 00:20:21,800 Like most revolutions, 288 00:20:21,934 --> 00:20:24,867 this one brought change that was both great, 289 00:20:25,000 --> 00:20:26,600 and horrifying. 290 00:20:26,734 --> 00:20:30,533 There was a new concept in the world, "Home." 291 00:20:31,734 --> 00:20:34,867 A specific place on the planet where your ancestors, 292 00:20:35,000 --> 00:20:38,300 and you, were born and lived. 293 00:20:38,767 --> 00:20:41,633 And over time these settlements grew larger, 294 00:20:41,767 --> 00:20:47,367 until about 20 cosmic seconds ago or around 7000 BCE. 295 00:20:53,667 --> 00:20:56,100 Welcome to Çatalhöyük, 296 00:20:56,233 --> 00:20:58,734 a community on the Anatolian plain. 297 00:20:58,867 --> 00:21:01,967 It's about 9,000 years ago and everyone has settled 298 00:21:02,100 --> 00:21:04,200 in for the evening. 299 00:21:04,533 --> 00:21:07,533 Tonight, roughly the same number of people who once 300 00:21:07,667 --> 00:21:11,300 populated all of Africa are living together 301 00:21:11,433 --> 00:21:13,667 in this proto-city. 302 00:21:14,300 --> 00:21:16,800 The city is such a new idea, 303 00:21:16,934 --> 00:21:19,266 they haven't invented the street yet, 304 00:21:19,400 --> 00:21:21,066 or the window. 305 00:21:21,200 --> 00:21:23,900 So the only way you can get into your apartment is to walk 306 00:21:24,033 --> 00:21:26,934 along the rooftops till you arrive at the opening 307 00:21:27,066 --> 00:21:28,567 to your dwelling. 308 00:21:30,033 --> 00:21:32,967 Çatalhöyük lacked something much more significant than 309 00:21:33,100 --> 00:21:36,233 streets and windows. 310 00:21:36,867 --> 00:21:40,066 There is no palace here. 311 00:21:40,200 --> 00:21:42,767 The bitter price that the invention of agriculture cost 312 00:21:42,900 --> 00:21:45,967 human society had yet to be paid. 313 00:21:46,266 --> 00:21:50,100 Here, there was no dominance of the few over the many. 314 00:21:50,233 --> 00:21:53,600 There was no 1% attaining lavish wealth, 315 00:21:53,734 --> 00:21:56,800 while most everyone else merely subsisted. 316 00:21:56,934 --> 00:22:00,100 Forensic analysis of the women, men, and children 317 00:22:00,233 --> 00:22:03,600 who lived here show a remarkable similarity in diet. 318 00:22:04,967 --> 00:22:09,100 They still cherished the hunter-gatherer ethos of sharing. 319 00:22:09,734 --> 00:22:12,900 Çatalhöyük was egalitarian. 320 00:22:13,033 --> 00:22:16,166 The weakest ate the same food that the strongest did, 321 00:22:17,133 --> 00:22:20,333 and everyone lived in the same kind of home. 322 00:22:20,834 --> 00:22:23,333 But, man, it was anything but drab. 323 00:22:23,467 --> 00:22:26,233 Come on. I'll show you. 324 00:22:40,900 --> 00:22:44,300 TYSON: This was a typical apartment in one of the first cities, 325 00:22:45,300 --> 00:22:47,567 Çatalhöyük, in what is now Turkey, 326 00:22:47,700 --> 00:22:50,333 as it looked about 9,000 years ago. 327 00:22:52,533 --> 00:22:55,200 They were a lot like us. 328 00:22:56,734 --> 00:22:59,166 This bit of volcanic glass, 329 00:22:59,300 --> 00:23:01,800 called obsidian, made an excellent mirror. 330 00:23:05,133 --> 00:23:08,533 If we could only find a way to see all the things 331 00:23:08,667 --> 00:23:10,533 that were once reflected here. 332 00:23:14,200 --> 00:23:16,233 This apartment was home for an extended family of 333 00:23:16,367 --> 00:23:18,400 seven to ten people. 334 00:23:18,533 --> 00:23:20,500 Every apartment had a similar floor plan. 335 00:23:21,700 --> 00:23:26,633 Bedroom. Living room. Kitchen. 336 00:23:29,700 --> 00:23:32,000 Plaster auroch head. 337 00:23:32,133 --> 00:23:35,734 The people of Çatalhöyük had a passion for decorating. 338 00:23:36,033 --> 00:23:38,834 Apartments were richly appointed with the teeth and 339 00:23:38,967 --> 00:23:41,166 bones and skins of animals. 340 00:23:42,233 --> 00:23:44,900 The ocher that our ancestors picked up in Africa, 341 00:23:45,033 --> 00:23:48,600 about 100,000 years before, was now the medium of choice 342 00:23:49,667 --> 00:23:52,400 for the interior decorators of Çatalhöyük. 343 00:23:57,266 --> 00:24:00,166 And the red ocher had yet another profound application. 344 00:24:01,233 --> 00:24:04,800 They used it to create an entirely new art form: 345 00:24:05,133 --> 00:24:06,667 the map. 346 00:24:06,800 --> 00:24:09,100 For the first time ever, humans created a 347 00:24:09,233 --> 00:24:12,300 two-dimensional representation of their location 348 00:24:12,433 --> 00:24:14,867 in space and time. 349 00:24:16,400 --> 00:24:20,567 "This is where my home is in relation to the volcano." 350 00:24:21,633 --> 00:24:23,600 And with a few magical strokes, 351 00:24:23,734 --> 00:24:26,867 the artist sent a message across 9,000 years... 352 00:24:27,767 --> 00:24:31,533 "I was here when the volcano awakened." 353 00:24:40,433 --> 00:24:43,433 The experiment at Çatalhöyük was a success, 354 00:24:43,567 --> 00:24:47,000 and within a few thousand years there were cities everywhere. 355 00:24:57,033 --> 00:25:02,600 ♪ ♪ 356 00:25:04,567 --> 00:25:06,734 TYSON: When different kinds of people congregate 357 00:25:06,867 --> 00:25:08,066 in a single place, 358 00:25:08,200 --> 00:25:11,000 ideas are exchanged and new possibilities arise. 359 00:25:12,100 --> 00:25:14,400 The city is a kind of brain, 360 00:25:14,533 --> 00:25:16,967 creating and processing new ideas. 361 00:25:20,133 --> 00:25:22,200 Here, in the city of Amsterdam, 362 00:25:22,333 --> 00:25:24,767 in the 17th century, citizens of the old and 363 00:25:24,900 --> 00:25:27,567 new worlds mingled as they never had before, 364 00:25:28,500 --> 00:25:30,934 and there was an unprecedented freedom of thought. 365 00:25:31,867 --> 00:25:35,767 These conditions produced a golden age of science and art. 366 00:25:36,467 --> 00:25:39,567 In Italy, Giordano Bruno had proclaimed the existence 367 00:25:39,700 --> 00:25:41,166 of other worlds. 368 00:25:41,300 --> 00:25:44,834 For this he had been made to suffer. 369 00:25:45,867 --> 00:25:48,233 But a mere 50 years later in Holland, 370 00:25:48,367 --> 00:25:50,166 the astronomer Christiaan Huygens, 371 00:25:50,300 --> 00:25:53,533 who held the same belief, was showered with honors. 372 00:25:56,400 --> 00:26:00,133 Light was the central theme of the age: 373 00:26:00,533 --> 00:26:04,500 The enlightenment of human curiosity set free, 374 00:26:04,834 --> 00:26:07,266 and the light shed by Europe's first look at 375 00:26:07,400 --> 00:26:10,133 the once hidden realms of the planet. 376 00:26:10,900 --> 00:26:14,066 The light that permeated the paintings of the time, 377 00:26:14,200 --> 00:26:16,900 particularly the work of Vermeer. 378 00:26:18,200 --> 00:26:21,500 And light as an object of scientific inquiry. 379 00:26:22,700 --> 00:26:25,867 For generations, textile merchants had used a lens to 380 00:26:26,000 --> 00:26:28,400 examine the thread count of finely stitched fabrics. 381 00:26:29,533 --> 00:26:31,367 In the Amsterdam of that time, 382 00:26:31,500 --> 00:26:33,467 there lived three men whose passion for 383 00:26:33,600 --> 00:26:37,967 light inspired them to use that ancient device in a completely new way. 384 00:26:39,367 --> 00:26:42,467 They aimed the textile merchants' lens at objects no 385 00:26:42,600 --> 00:26:45,734 one had ever thought to examine closely before. 386 00:26:46,200 --> 00:26:49,266 It became a window, an aperture for finding and 387 00:26:49,400 --> 00:26:51,867 exploring new worlds. 388 00:26:52,266 --> 00:26:55,633 Antonie Van Leeuwenhoek used a single lens to reveal 389 00:26:55,767 --> 00:26:58,533 the teeming microcosm in a drop of water. 390 00:27:06,400 --> 00:27:07,700 His friend, 391 00:27:07,834 --> 00:27:10,333 Christiaan Huygens used two lenses to bring the stars, 392 00:27:10,467 --> 00:27:13,133 planets, and moons close enough to 393 00:27:13,266 --> 00:27:15,233 reveal their features. 394 00:27:15,967 --> 00:27:19,133 Huygens became the first to see that Saturn's rings did not 395 00:27:19,266 --> 00:27:23,500 touch the planet, and the first to understand what they really were. 396 00:27:25,166 --> 00:27:28,066 He also discovered Saturn's largest moon, Titan. 397 00:27:29,567 --> 00:27:31,133 Huygens, like Bruno, 398 00:27:31,266 --> 00:27:33,867 believed that the stars were other suns, 399 00:27:34,000 --> 00:27:37,266 orbited by their own systems of planets and moons. 400 00:27:37,900 --> 00:27:40,200 But why was there no hint of those other worlds and 401 00:27:40,333 --> 00:27:44,433 their living things in the sacred books? 402 00:27:45,934 --> 00:27:48,633 Whatever disquiet this contradiction may have stirred 403 00:27:48,767 --> 00:27:52,000 in the hearts and minds of the leaders of the Enlightenment, 404 00:27:52,133 --> 00:27:55,667 there was only one man who dared to address it head-on. 405 00:27:56,000 --> 00:27:58,767 He was another wizard of light. 406 00:27:58,900 --> 00:28:01,333 Baruch Spinoza had been a member of the Jewish 407 00:28:01,467 --> 00:28:04,000 congregation of Amsterdam through his teenage years. 408 00:28:05,166 --> 00:28:07,867 But in his early 20s, he began to speak publicly of 409 00:28:08,000 --> 00:28:10,300 a new vision of God. 410 00:28:11,667 --> 00:28:14,633 Spinoza's God was the physical laws of the universe. 411 00:28:16,500 --> 00:28:19,633 His sacred text, the book of nature. 412 00:28:22,367 --> 00:28:24,567 The Jews of Amsterdam were mostly refugees from 413 00:28:24,700 --> 00:28:27,633 the vicious Inquisitions in Spain and Portugal, 414 00:28:28,000 --> 00:28:30,900 where so many of them had been tortured and murdered. 415 00:28:32,900 --> 00:28:35,900 Amsterdam had offered the Jews a refuge, 416 00:28:36,033 --> 00:28:38,400 and they must have seen Spinoza's radical ideas as a 417 00:28:38,533 --> 00:28:41,567 threat to their hard-won security in Holland. 418 00:28:42,233 --> 00:28:44,133 They excommunicated the young rebel, 419 00:28:44,266 --> 00:28:46,867 and decreed that he must be forever shunned. 420 00:28:47,533 --> 00:28:50,734 Spinoza accepted their punishment with dignity, 421 00:28:50,867 --> 00:28:53,400 but without a trace of submission. 422 00:28:53,533 --> 00:28:55,500 He moved nearby, to The Hague. 423 00:28:55,633 --> 00:28:58,900 Where he went even further, daring to write that the Bible 424 00:28:59,033 --> 00:29:02,834 was not dictated by God, but written by human beings. 425 00:29:03,333 --> 00:29:04,767 Spinoza wrote: 426 00:29:04,900 --> 00:29:07,100 "Do not look for God in miracles. 427 00:29:07,233 --> 00:29:10,100 Miracles are violations of the laws of nature. 428 00:29:10,633 --> 00:29:13,633 God is best apprehended in the study of those laws." 429 00:29:15,467 --> 00:29:18,233 No one had ever said these things aloud before. 430 00:29:18,800 --> 00:29:22,200 Spinoza knew that he was testing the limits of free thought, 431 00:29:22,333 --> 00:29:24,367 even for Holland. 432 00:29:27,500 --> 00:29:30,867 To him, an official state religion was more than 433 00:29:31,000 --> 00:29:34,166 spiritual coercion of the individual. 434 00:29:34,300 --> 00:29:37,500 Spinoza regarded the miraculous events of the major 435 00:29:37,633 --> 00:29:40,900 religious traditions as organized superstition. 436 00:29:42,400 --> 00:29:45,967 In his view, magical thinking posed a danger to 437 00:29:46,100 --> 00:29:49,867 the future citizens of a rational, free society. 438 00:29:51,000 --> 00:29:53,600 There could be no such thing as democracy without the 439 00:29:53,734 --> 00:29:56,433 separation of church and state. 440 00:29:56,567 --> 00:29:59,300 He wrote a book that introduced the ideas at the 441 00:29:59,433 --> 00:30:02,800 heart of the American and many another revolution. 442 00:30:04,800 --> 00:30:07,734 Then, as now, there were those who were threatened 443 00:30:07,867 --> 00:30:09,834 by this view of God. 444 00:30:10,633 --> 00:30:12,100 (grunting). 445 00:30:20,967 --> 00:30:23,500 Spinoza continued to write and speak about his 446 00:30:23,633 --> 00:30:26,133 revolutionary view of God, 447 00:30:26,266 --> 00:30:29,100 always wearing the slashed cape as a badge of honor. 448 00:30:31,300 --> 00:30:35,266 He died at 44, possibly from inhaling particles of dust 449 00:30:35,400 --> 00:30:37,333 during his years of grinding lenses for 450 00:30:37,467 --> 00:30:39,633 microscopes and telescopes. 451 00:30:40,934 --> 00:30:44,800 250 years later, another man with a passion for light made 452 00:30:44,934 --> 00:30:47,400 a pilgrimage to the humble workroom that had been 453 00:30:47,533 --> 00:30:50,133 preserved as a testament to the vast influence of 454 00:30:50,266 --> 00:30:52,300 Spinoza's philosophy. 455 00:30:52,433 --> 00:30:56,166 This man, world famous for finding a new law of nature, 456 00:30:56,300 --> 00:30:59,500 was often asked if he believed in God. 457 00:30:59,633 --> 00:31:01,633 Albert Einstein replied: 458 00:31:02,233 --> 00:31:08,300 "I believe in Spinoza's God, who reveals himself in the harmony of all that exists." 459 00:31:12,233 --> 00:31:15,500 Our understanding of nature's laws has advanced far beyond 460 00:31:15,633 --> 00:31:18,667 Spinoza's, and even Einstein's wildest dreams. 461 00:31:19,967 --> 00:31:23,600 But there is one law of nature we cannot seem to grasp. 462 00:31:24,200 --> 00:31:27,033 Inscribed in the book of nature is a parable about an 463 00:31:27,166 --> 00:31:29,800 ancient alliance between two kingdoms. 464 00:31:30,533 --> 00:31:33,667 And those who would tear it apart. 465 00:31:46,333 --> 00:31:48,967 TYSON: Long ago, there were two kingdoms. 466 00:31:49,100 --> 00:31:51,400 An alliance was formed between them, 467 00:31:51,533 --> 00:31:54,533 one that would bring them both riches beyond measure. 468 00:31:55,200 --> 00:31:59,400 A partnership lasting more than a 100 million years. 469 00:31:59,533 --> 00:32:03,700 And then a new kind of being evolved in one of the two kingdoms. 470 00:32:04,233 --> 00:32:08,834 Its descendants plundered the riches and violated the alliance. 471 00:32:09,200 --> 00:32:12,567 In their arrogance, they became a mortal danger to both 472 00:32:12,700 --> 00:32:15,500 kingdoms and to themselves. 473 00:32:27,166 --> 00:32:29,433 This parable is true. 474 00:32:29,567 --> 00:32:33,266 It's the story of two of the half dozen realms of life on Earth, 475 00:32:33,400 --> 00:32:36,467 the plant and animal kingdoms. 476 00:32:37,166 --> 00:32:39,967 It's not easy being green. 477 00:32:41,133 --> 00:32:44,600 Sex is challenging when you're stuck in one place. 478 00:32:44,734 --> 00:32:46,000 There's no dating. 479 00:32:46,133 --> 00:32:49,033 You just sit there and cast your seed to the winds. 480 00:32:50,200 --> 00:32:51,633 Literally. 481 00:32:51,767 --> 00:32:54,200 You just wait for the wind to blow. 482 00:32:54,333 --> 00:32:56,467 If you get lucky, some of your pollen will 483 00:32:56,600 --> 00:32:59,500 be carried away and land on the sexual reproductive part 484 00:32:59,633 --> 00:33:02,066 of another plant. 485 00:33:02,200 --> 00:33:04,600 The plants played this hit-or-miss game of chance for 486 00:33:04,734 --> 00:33:06,967 a couple of hundred million years, 487 00:33:07,100 --> 00:33:10,834 until insects evolved to play cupid. 488 00:33:15,000 --> 00:33:17,800 What resulted was one of the great co-evolution marriages 489 00:33:17,934 --> 00:33:19,800 in the history of life. 490 00:33:19,934 --> 00:33:22,333 The insect would visit a flower for a dinner of 491 00:33:22,467 --> 00:33:24,667 protein-rich pollen. 492 00:33:24,800 --> 00:33:27,633 Inevitably, some of the pollen would stick to the body 493 00:33:27,767 --> 00:33:29,467 of the insect. 494 00:33:29,600 --> 00:33:31,500 The insect would visit another flower, 495 00:33:31,633 --> 00:33:34,367 bringing along the leftovers on its body. 496 00:33:34,934 --> 00:33:37,967 That pollen fertilized the next flower, 497 00:33:38,100 --> 00:33:40,333 allowing it to reproduce. 498 00:33:41,233 --> 00:33:44,467 It was a win-win deal for both the flowers and the insects, 499 00:33:45,300 --> 00:33:48,000 causing a series of delightful evolutionary developments. 500 00:33:49,233 --> 00:33:52,100 A new plant arose that produced sugary nectar in 501 00:33:52,233 --> 00:33:54,033 addition to the pollen. 502 00:33:54,166 --> 00:33:58,000 Now, the insects came not just for their basic meal of pollen, 503 00:33:58,667 --> 00:34:01,066 but also for dessert. 504 00:34:01,667 --> 00:34:05,166 The insects got chubbier, evolved furry bodies and even 505 00:34:05,300 --> 00:34:08,400 little pouches on their legs to snag more pollen on their 506 00:34:08,533 --> 00:34:10,767 daily rounds in the flowers. 507 00:34:13,066 --> 00:34:15,300 Now there were bees. 508 00:34:16,433 --> 00:34:18,533 This was a bonus for yet another species of 509 00:34:18,667 --> 00:34:20,367 the animal kingdom... 510 00:34:20,500 --> 00:34:22,300 Us. 511 00:34:25,734 --> 00:34:28,567 We are indebted to the bees and their fellow pollinators 512 00:34:28,700 --> 00:34:32,000 for something even more vital to our survival. 513 00:34:32,300 --> 00:34:35,700 Every third bite of food you take-and this is even true for 514 00:34:35,834 --> 00:34:39,633 those of us who are omnivores, was made possible by them. 515 00:34:40,467 --> 00:34:44,000 35% of the world's crops depend on their cooperation. 516 00:34:44,867 --> 00:34:47,100 The plants eat starlight... 517 00:34:47,233 --> 00:34:50,567 And we, and the animals, we eat plants. 518 00:34:51,600 --> 00:34:54,734 And they don't just increase the quantity of available food. 519 00:34:54,867 --> 00:34:57,767 We owe them for much of the biodiversity that has made our 520 00:34:57,900 --> 00:35:01,200 food supply so dependable. 521 00:35:01,333 --> 00:35:03,700 But we're working them to death. 522 00:35:03,834 --> 00:35:05,400 And for the first time ever, 523 00:35:05,533 --> 00:35:10,066 many kinds of bees are on the endangered species list. 524 00:35:22,066 --> 00:35:25,000 I think you know where this is headed. 525 00:35:34,300 --> 00:35:37,900 The blessing and the curse of the invention of agriculture 526 00:35:38,033 --> 00:35:40,467 has brought us here, to the Halls of Extinction. 527 00:35:51,133 --> 00:35:55,333 A memorial to all the living things lost in the mass 528 00:35:55,467 --> 00:35:58,033 extinction events in Earth's history. 529 00:35:58,934 --> 00:36:03,600 It's a monument to the broken branches on the tree of life. 530 00:36:04,633 --> 00:36:07,500 Five times in the history of life, 531 00:36:07,633 --> 00:36:11,133 cataclysmic geological, and astronomical events, 532 00:36:11,266 --> 00:36:15,867 have threatened to extinguish life itself. 533 00:36:17,533 --> 00:36:20,867 The sixth one is different. 534 00:36:21,133 --> 00:36:24,266 The last time we were here together this hallway 535 00:36:24,400 --> 00:36:26,000 had no name. 536 00:36:26,133 --> 00:36:27,333 Why? 537 00:36:27,467 --> 00:36:30,000 Because back then a scientific consensus had yet 538 00:36:30,133 --> 00:36:34,533 to be reached that we were in the midst of a mass extinction event. 539 00:36:35,266 --> 00:36:36,800 That's changed. 540 00:36:36,934 --> 00:36:40,100 Now, this hallway has a name. 541 00:36:40,800 --> 00:36:42,867 It's ours. 542 00:36:43,000 --> 00:36:46,066 The Anthropocene. 543 00:36:47,400 --> 00:36:52,633 "Anthropo" from the Greek word for "human" and "Cene." 544 00:36:54,200 --> 00:36:56,900 the Greek word for "recent." 545 00:37:14,333 --> 00:37:17,100 TYSON: These are the species we hunted to extinction back 546 00:37:17,233 --> 00:37:19,633 when we were wanderers. 547 00:37:19,900 --> 00:37:23,367 Including our own cousins, the Neanderthals. 548 00:37:38,867 --> 00:37:41,200 What is it about us, as a species, 549 00:37:41,333 --> 00:37:45,133 that wherever we go, we bring death? 550 00:37:49,233 --> 00:37:52,333 Beyond here lies the future. 551 00:37:52,467 --> 00:37:56,367 Even now it's not too late to keep this corridor from lengthening. 552 00:37:58,467 --> 00:38:01,266 If we fail... 553 00:38:04,767 --> 00:38:08,033 (children playing). 554 00:38:12,600 --> 00:38:15,233 But if we succeed... 555 00:38:15,567 --> 00:38:17,333 Come with me. 556 00:38:30,834 --> 00:38:34,400 TYSON: In a possible future only decades away, 557 00:38:34,533 --> 00:38:38,934 project Starshot, a flotilla of 1,000 spacecraft, 558 00:38:39,066 --> 00:38:41,233 will depart from Earth. 559 00:38:41,367 --> 00:38:44,467 This part of the Atacama Desert west of the Andes Mountains, 560 00:38:44,600 --> 00:38:47,934 is so dry that it hasn't rained in recorded history. 561 00:38:49,367 --> 00:38:52,400 And that's great for us because we're going to need 562 00:38:52,533 --> 00:38:54,367 the clearest of skies. 563 00:39:26,567 --> 00:39:29,066 There were no witnesses when the first life left the 564 00:39:29,200 --> 00:39:32,100 water for the land. 565 00:39:32,400 --> 00:39:34,967 There was nobody to file a report when the first birds 566 00:39:35,100 --> 00:39:37,367 took to the skies. 567 00:39:37,500 --> 00:39:40,033 But this is one great leap that will be documented in 568 00:39:40,166 --> 00:39:42,600 every conceivable way. 569 00:39:42,734 --> 00:39:45,266 The whole world is watching. 570 00:39:46,166 --> 00:39:49,166 We are, after all, sending our first craft directly to the 571 00:39:49,300 --> 00:39:52,900 planets of another sun: the Alpha Centauri system. 572 00:39:56,300 --> 00:39:59,667 These are the ships that will carry our senses there. 573 00:39:59,800 --> 00:40:03,500 These are interstellar sailing ships propelled by light. 574 00:40:04,133 --> 00:40:07,700 Their hulls weigh but a gram, and they are no larger than a 575 00:40:07,834 --> 00:40:11,367 pea, and yet they're equipped with all that NASA's Voyagers 576 00:40:11,500 --> 00:40:13,633 have and more. 577 00:40:23,166 --> 00:40:26,166 When the first light blasts forth from this phased array 578 00:40:26,300 --> 00:40:30,533 of lasers, the spacecraft will accelerate from zero to 20% of 579 00:40:30,667 --> 00:40:34,200 the speed of light in mere minutes. 580 00:40:34,467 --> 00:40:37,400 Inside each nanocraft is everything needed to perform 581 00:40:37,533 --> 00:40:41,400 the preliminary reconnaissance of the worlds of another star 582 00:40:41,533 --> 00:40:44,567 and return that visual and scientific information 583 00:40:44,700 --> 00:40:46,800 back to Earth. 584 00:40:48,166 --> 00:40:50,533 Space is mostly empty, 585 00:40:50,667 --> 00:40:52,600 but there are tiny dust particles that could 586 00:40:52,734 --> 00:40:55,467 wreak havoc if they were to collide with nanocraft 587 00:40:55,600 --> 00:40:57,467 traveling at such high speeds. 588 00:41:08,800 --> 00:41:11,233 That's one of the reasons we need to send so many of them. 589 00:41:17,967 --> 00:41:21,600 Voyager 1 is traveling at 38,000 miles per hour. 590 00:41:22,667 --> 00:41:25,767 It left home more than 40 years ago. 591 00:41:27,066 --> 00:41:29,700 It will take these nanocraft only four days 592 00:41:29,834 --> 00:41:31,400 to overtake her. 593 00:41:31,533 --> 00:41:33,033 That's pretty fast, 594 00:41:33,166 --> 00:41:36,066 but still only 20% of the speed of light. 595 00:41:36,200 --> 00:41:39,300 Proxima Centauri is four light-years away. 596 00:41:39,433 --> 00:41:41,600 That's a 20 year one-way trip. 597 00:41:44,567 --> 00:41:47,100 Orbiting Proxima Centauri, there is a world in the 598 00:41:47,233 --> 00:41:50,934 habitable zone where we think life might flourish. 599 00:41:53,934 --> 00:41:56,333 Our robotic emissaries will send accounts from 600 00:41:56,467 --> 00:41:59,166 these new worlds. 601 00:41:59,467 --> 00:42:02,033 Their messages will race back to us on radio waves 602 00:42:02,166 --> 00:42:03,967 at the speed of light. 603 00:42:04,100 --> 00:42:07,667 They'll take four years to reach us: 20 years one-way, 604 00:42:08,367 --> 00:42:10,233 four years back. 605 00:42:10,367 --> 00:42:13,367 That's a 24-year round-trip. 606 00:42:13,734 --> 00:42:18,266 Many of you will be there then to read and to write those new 607 00:42:18,400 --> 00:42:20,700 pages in the book of nature, 608 00:42:20,834 --> 00:42:23,767 and to chart our future course of wandering... 609 00:42:42,133 --> 00:42:46,767 ♪ ♪ 610 00:42:47,433 --> 00:42:49,834 No longer bounded by the earth, 611 00:42:49,967 --> 00:42:52,567 the ocean, 612 00:42:52,700 --> 00:42:55,433 or the sky. 613 00:43:06,934 --> 00:43:13,266 ♪ ♪ 614 00:43:14,133 --> 00:43:15,967 Captioned by Cotter Captioning Services.