1 00:00:22,730 --> 00:00:25,230 We were hunters and foragers. 2 00:00:26,000 --> 00:00:28,800 The frontier was everywhere. 3 00:00:37,100 --> 00:00:42,000 We were bounded only by the earth and the ocean and the sky. 4 00:00:49,530 --> 00:00:54,130 The open road still softly calls like a nearly forgotten 5 00:00:54,260 --> 00:00:56,260 song of childhood. 6 00:00:57,230 --> 00:01:00,660 For all our failings, despite our limitations and 7 00:01:00,800 --> 00:01:04,760 fallibilities, we humans are capable of greatness. 8 00:01:10,560 --> 00:01:14,530 How far will our nomadic species have wandered by the 9 00:01:14,660 --> 00:01:17,200 end of the next century? 10 00:01:19,000 --> 00:01:21,800 And the next millennium? 11 00:01:49,030 --> 00:01:52,730 Welcome back to the shores of the cosmic ocean... 12 00:01:53,100 --> 00:01:55,060 An immensity of space and time, 13 00:01:56,230 --> 00:01:58,700 a vastness still mostly uncharted. 14 00:01:59,500 --> 00:02:03,200 We're bound for the possible worlds revealed by science. 15 00:02:03,960 --> 00:02:07,400 We'll take a ride on the underground worldwide network 16 00:02:07,530 --> 00:02:09,260 that no one knew was there. 17 00:02:10,200 --> 00:02:13,330 I'm going to tell you a first contact story that's true. 18 00:02:16,330 --> 00:02:19,200 We'll meet some of the most courageous people who ever lived. 19 00:02:20,500 --> 00:02:25,360 And we're going to venture into the future we can still have, 20 00:02:25,900 --> 00:02:30,230 to the homes of our distant descendants among the starts. 21 00:02:31,000 --> 00:02:34,100 Science can carry us across that vastness. 22 00:02:34,230 --> 00:02:36,900 But without imagination, we go nowhere. 23 00:02:39,130 --> 00:02:42,530 Our Ship of the Imagination is propelled by twin engines 24 00:02:42,660 --> 00:02:44,860 of skepticism and wonder. 25 00:02:45,530 --> 00:02:49,660 It's guided by the simple set of rules that define science 26 00:02:49,800 --> 00:02:51,130 and make it so powerful. 27 00:02:54,800 --> 00:02:57,830 Test ideas by experiment and observation. 28 00:02:57,960 --> 00:03:00,560 Build on those ideas that pass the test. 29 00:03:01,260 --> 00:03:03,360 Reject the ones that fail. 30 00:03:03,500 --> 00:03:06,330 Follow the evidence wherever it leads. 31 00:03:06,460 --> 00:03:08,600 And question everything. 32 00:03:09,400 --> 00:03:13,800 Take these rules to heart, and the cosmos is yours. 33 00:03:14,800 --> 00:03:17,000 Come with me... 34 00:04:48,630 --> 00:04:51,500 Our Ship of the Imagination can take us 35 00:04:51,630 --> 00:04:54,560 anywhere in space and time. 36 00:04:56,030 --> 00:04:59,130 The cosmos is right outside our front window. 37 00:05:00,330 --> 00:05:03,600 If you want to see the past, look down. 38 00:05:16,330 --> 00:05:19,400 And if you want to see the future, look up. 39 00:05:33,060 --> 00:05:36,900 On this voyage, we are bound for a distant galaxy. 40 00:05:38,960 --> 00:05:42,460 And we'll discover how we as a species became 41 00:05:42,600 --> 00:05:44,800 explorers of the cosmos. 42 00:05:45,600 --> 00:05:47,930 There. There she is. 43 00:05:48,060 --> 00:05:50,200 NASA's Voyager 1. 44 00:05:50,330 --> 00:05:52,560 Launched in 1977, 45 00:05:52,700 --> 00:05:55,460 she is the most distant object built by human hands. 46 00:05:56,860 --> 00:05:59,360 She's done some hard traveling since our last encounter, 47 00:06:00,030 --> 00:06:02,330 logged another billion and a half miles. 48 00:06:02,930 --> 00:06:06,260 Voyager's making for other parts of our Milky Way, 49 00:06:06,400 --> 00:06:09,700 but we have another, far more distant destination. 50 00:06:10,930 --> 00:06:14,160 The cosmic ocean is made of space and time. 51 00:06:14,960 --> 00:06:18,000 You can't move in space without also moving in time. 52 00:06:18,800 --> 00:06:21,830 Our voyage will take us a long way from home, 53 00:06:22,160 --> 00:06:25,230 a little more than a billion light-years. 54 00:06:25,360 --> 00:06:28,860 We're also traveling a billion years into the past, 55 00:06:29,000 --> 00:06:32,330 to an event so violent it will even shatter time. 56 00:06:43,830 --> 00:06:46,260 Now, we're getting close to our destination. 57 00:06:46,400 --> 00:06:48,700 This is what we came for. 58 00:06:51,800 --> 00:06:54,460 These two black holes were born from the collapse of a 59 00:06:54,600 --> 00:06:57,400 pair of massive stars. 60 00:06:58,060 --> 00:07:00,560 And they've been doing a gravitational tango ever since 61 00:07:00,960 --> 00:07:02,660 for millions of years. 62 00:07:02,800 --> 00:07:05,200 We're here for the climax. 63 00:07:05,460 --> 00:07:08,300 When those two collide, they will set off a space-time 64 00:07:08,430 --> 00:07:10,800 tsunami that will stretch and compress space 65 00:07:10,930 --> 00:07:12,460 in all directions. 66 00:07:12,600 --> 00:07:15,230 And it will slow down time itself, 67 00:07:15,360 --> 00:07:17,930 before speeding it up and slowing it down again. 68 00:07:44,700 --> 00:07:47,900 Gravitational... 69 00:07:48,430 --> 00:07:51,300 and it will slow down time itself... 70 00:07:52,860 --> 00:07:55,960 Set off a space-time tsunami... 71 00:07:56,300 --> 00:07:59,330 Stretch and compress space in all directions a billion 72 00:07:59,460 --> 00:08:01,260 light-years away. 73 00:08:09,900 --> 00:08:11,776 What does an event that took place more than a billion 74 00:08:11,800 --> 00:08:14,960 light-years away have to do with us? 75 00:08:15,460 --> 00:08:18,330 Albert Einstein was the first to understand that matter 76 00:08:18,460 --> 00:08:21,130 could send ripples across space-time. 77 00:08:21,500 --> 00:08:24,030 He imagined that catastrophic explosions of matter should 78 00:08:24,160 --> 00:08:27,500 create something much bigger than ripples, great waves, 79 00:08:28,500 --> 00:08:30,530 gravitational waves. 80 00:08:30,660 --> 00:08:33,500 You are seeing and hearing me right now, 81 00:08:33,630 --> 00:08:36,860 on whatever device you have, because we figured out a way 82 00:08:37,000 --> 00:08:39,960 to manipulate the electromagnetic spectrum. 83 00:08:40,300 --> 00:08:42,660 If we can learn to surf those gravitational waves the 84 00:08:42,800 --> 00:08:45,800 way we know how to ride the electromagnetic ones, 85 00:08:45,930 --> 00:08:47,530 who knows? 86 00:08:47,660 --> 00:08:50,860 It's as impossible to foresee as our world was to the 87 00:08:51,060 --> 00:08:53,460 scientists who experimented with electricity back 88 00:08:53,600 --> 00:08:56,100 in the 19th century. 89 00:08:56,230 --> 00:08:59,100 Cosmologists predicted the existence of black holes. 90 00:09:00,200 --> 00:09:03,560 Gravitational waves are the first direct evidence that 91 00:09:03,700 --> 00:09:05,900 black holes are real. 92 00:09:06,030 --> 00:09:08,460 But they may also provide a new way of knowing and 93 00:09:08,600 --> 00:09:10,300 exploring the cosmos. 94 00:09:10,430 --> 00:09:12,930 We can add it to the other senses that science has 95 00:09:13,060 --> 00:09:16,600 devised to penetrate the great dark ocean, 96 00:09:16,730 --> 00:09:19,660 all the kinds of light we use; gamma ray, 97 00:09:22,600 --> 00:09:26,060 X-ray, ultraviolet, 98 00:09:27,800 --> 00:09:31,200 infrared, microwave, 99 00:09:32,700 --> 00:09:36,900 radio wave and visible light. 100 00:09:38,530 --> 00:09:41,660 This newest way to search the cosmos could help us to one 101 00:09:41,800 --> 00:09:45,230 day know what's happening inside those black holes, 102 00:09:46,330 --> 00:09:48,530 and the other hidden places that make up most 103 00:09:48,660 --> 00:09:50,630 of the universe. 104 00:09:50,760 --> 00:09:53,730 What if we could detect the gravitational waves that were 105 00:09:53,860 --> 00:09:56,160 caused by the first moment of creation, 106 00:09:57,400 --> 00:09:59,730 the birth of the cosmos? 107 00:10:01,600 --> 00:10:05,230 What if we could extend our vision to see the whole sweep 108 00:10:05,360 --> 00:10:08,660 of 14 billion years of cosmic evolution? 109 00:10:21,630 --> 00:10:24,230 So, how did we get so smart? 110 00:10:25,530 --> 00:10:28,600 We know something about the evolution of our species, 111 00:10:28,730 --> 00:10:31,360 but how did the human mind evolve? 112 00:10:32,560 --> 00:10:35,460 Where did that crazy ambition to climb the ladder to the 113 00:10:35,600 --> 00:10:37,330 stars come from? 114 00:10:38,100 --> 00:10:42,630 How did we become a way for the universe to know itself? 115 00:10:44,800 --> 00:10:47,630 It started over there. 116 00:10:53,860 --> 00:10:56,630 Is a way for us to grasp theCr 117 00:10:56,760 --> 00:10:58,760 vastness of time. 118 00:10:58,900 --> 00:11:00,500 We've taken all of time, 119 00:11:00,630 --> 00:11:03,100 from the birth of the universe to this very moment, 120 00:11:03,230 --> 00:11:06,230 and compressed it into a single calendar year. 121 00:11:06,360 --> 00:11:08,760 On this scale, every month represents a little 122 00:11:08,900 --> 00:11:10,960 more than a billion years. 123 00:11:11,100 --> 00:11:14,400 Every day represents nearly 40 million years. 124 00:11:16,130 --> 00:11:19,030 Our own story begins with all the other life on 125 00:11:19,160 --> 00:11:21,330 our little world. 126 00:11:21,460 --> 00:11:24,430 Every living thing on Earth is descended from 127 00:11:24,560 --> 00:11:26,460 a single origin. 128 00:11:26,600 --> 00:11:30,400 It happened in the deep ocean darkness on September 15, 129 00:11:30,530 --> 00:11:33,560 about four billion years ago. 130 00:11:34,560 --> 00:11:38,900 Within this tiny single-celled organism was a kind of chemical ladder, 131 00:11:40,030 --> 00:11:42,430 the DNA double helix. 132 00:11:44,460 --> 00:11:46,860 Star stuff... 133 00:11:47,230 --> 00:11:50,160 Oxygen, carbon, nitrogen... 134 00:11:50,300 --> 00:11:53,330 Elements cooked in the hearts of distant stars, 135 00:11:53,460 --> 00:11:56,830 combined with hydrogen from the Big Bang to become alive 136 00:11:56,960 --> 00:11:59,230 on this little world. 137 00:11:59,530 --> 00:12:02,930 Through random changes, mutations in the genes, 138 00:12:03,060 --> 00:12:05,700 some of which led to more successful life-forms, 139 00:12:05,830 --> 00:12:08,330 what we call evolution by natural selection. 140 00:12:09,160 --> 00:12:13,830 The ladder grew, adding more and more rungs. 141 00:12:15,430 --> 00:12:18,960 It took another three billion years for life to evolve the 142 00:12:19,100 --> 00:12:22,330 complexity of the plants and animals that you could see 143 00:12:22,460 --> 00:12:24,630 with the naked eye. 144 00:12:30,830 --> 00:12:33,560 If the Cosmic Calendar had holidays, 145 00:12:33,700 --> 00:12:36,600 surely December 26 would be one of them. 146 00:12:37,230 --> 00:12:40,460 Some time on this day, about 200 million years ago, 147 00:12:41,860 --> 00:12:44,160 the first mammals evolved. 148 00:12:44,530 --> 00:12:46,860 They brought a new feature to life on Earth: 149 00:12:47,000 --> 00:12:49,460 the neocortex. 150 00:12:50,560 --> 00:12:52,160 Back in the Triassic, 151 00:12:52,300 --> 00:12:55,830 the odds were against her kind, but the dinosaurs that 152 00:12:55,960 --> 00:12:58,800 terrorized the mammals went extinct. 153 00:12:59,930 --> 00:13:02,900 It was the evolution of the neocortex in small, 154 00:13:03,030 --> 00:13:05,030 furtive creatures such as this one, 155 00:13:05,560 --> 00:13:09,230 that enabled their descendants to take over the planet. 156 00:13:09,800 --> 00:13:13,030 Mammals brought something else that was new. 157 00:13:13,330 --> 00:13:15,060 They suckled their young. 158 00:13:15,900 --> 00:13:17,800 They nurtured them. 159 00:13:17,930 --> 00:13:20,230 And there was love. 160 00:13:21,660 --> 00:13:24,860 Mother's Day on the Cosmic Calendar. 161 00:13:28,100 --> 00:13:31,600 Evolution by natural selection means that those living things 162 00:13:31,730 --> 00:13:34,830 able to better adapt to their environment are more likely to 163 00:13:34,960 --> 00:13:37,330 survive and leave offspring. 164 00:13:38,060 --> 00:13:41,700 Intelligence can be a huge selective advantage. 165 00:13:42,060 --> 00:13:45,860 The fate of this planet was changed forever by an event 166 00:13:46,000 --> 00:13:48,500 involving just 13 atoms. 167 00:13:48,800 --> 00:13:51,130 How small is 13 atoms? 168 00:13:51,260 --> 00:13:54,930 It's a quadrillionth the size of a grain of salt. 169 00:13:55,600 --> 00:13:59,460 A mutation occurred in the DNA of just one of our ancestors. 170 00:14:00,260 --> 00:14:03,960 Every source of self-esteem, everything we've learned, 171 00:14:04,100 --> 00:14:07,730 and built, might come down to nothing more than this. 172 00:14:09,600 --> 00:14:11,730 One base pair of a single gene. 173 00:14:12,760 --> 00:14:17,000 Just a single rung programmed the neocortex to grow larger 174 00:14:17,130 --> 00:14:19,130 still and fold more deeply. 175 00:14:19,930 --> 00:14:22,560 Maybe it was a random zap from a cosmic ray, 176 00:14:23,100 --> 00:14:26,200 or a simple error in transmission from one cell to another. 177 00:14:28,000 --> 00:14:31,800 Whatever it was, it led to a change in our species that 178 00:14:31,930 --> 00:14:34,460 would ultimately affect every other species 179 00:14:34,600 --> 00:14:37,130 of life on Earth. 180 00:14:37,800 --> 00:14:40,600 It happened late on New Year's Eve on this 181 00:14:40,730 --> 00:14:43,800 Cosmic Calendar of ours. 182 00:14:48,600 --> 00:14:51,060 To think that, for good or evil, 183 00:14:51,200 --> 00:14:54,400 our ability to feel loyalty and concern for increasingly 184 00:14:54,530 --> 00:14:58,030 larger groups, our obsession with certain belief systems, 185 00:14:58,700 --> 00:15:01,260 our capacity to imagine the future, 186 00:15:01,400 --> 00:15:05,530 our power to transform the world and to search the cosmos 187 00:15:05,660 --> 00:15:08,000 for answers... 188 00:15:08,330 --> 00:15:11,230 The very name we gave to our own species, 189 00:15:11,360 --> 00:15:15,560 homo sapiens, Latin for "wise persons" all of it 190 00:15:15,700 --> 00:15:20,200 comes down to nothing more than a single rung on our tiny 191 00:15:20,330 --> 00:15:22,500 DNA ladder to the stars. 192 00:15:26,130 --> 00:15:28,800 For much of the last hour on the Cosmic Calendar, 193 00:15:29,400 --> 00:15:31,700 for all but the last minute, 194 00:15:31,830 --> 00:15:34,200 our ancestors were hunters and gatherers, 195 00:15:35,700 --> 00:15:38,530 living in small bands. 196 00:15:44,860 --> 00:15:47,530 You know, when people just shrug and say 197 00:15:47,660 --> 00:15:50,860 "chalk it up to human nature," it puzzles me. 198 00:15:51,960 --> 00:15:54,030 They're usually talking about our greed, 199 00:15:54,160 --> 00:15:56,960 our arrogance, our violence. 200 00:15:57,100 --> 00:15:58,776 But we've been human for at least a couple of 201 00:15:58,800 --> 00:16:00,700 hundred thousand years. 202 00:16:00,830 --> 00:16:03,930 For most of that time we weren't that way at all. 203 00:16:04,800 --> 00:16:06,430 How do we know? 204 00:16:06,560 --> 00:16:09,130 From the accounts of explorers and anthropologists 205 00:16:09,260 --> 00:16:11,930 encountering surviving hunter-gatherer societies 206 00:16:12,060 --> 00:16:14,860 across four centuries. 207 00:16:15,000 --> 00:16:17,500 There are, of course, exceptions, especially in 208 00:16:17,630 --> 00:16:20,230 the circumstances of extreme scarcity. 209 00:16:20,360 --> 00:16:24,060 But the overwhelming consensus paints a picture of humans 210 00:16:24,200 --> 00:16:26,460 who lived in relative harmony with each other 211 00:16:26,600 --> 00:16:28,500 and the environment. 212 00:16:28,630 --> 00:16:31,500 We shared the little we had because we knew that our 213 00:16:31,630 --> 00:16:34,030 survival depended on the group. 214 00:16:34,600 --> 00:16:38,060 We didn't prize wealth beyond our needs because possessions 215 00:16:38,200 --> 00:16:40,230 would just weigh us down as we wandered. 216 00:16:41,230 --> 00:16:44,230 We were different from our non-human primate ancestors 217 00:16:44,360 --> 00:16:47,500 with their alpha-males bullying their way to dominance. 218 00:16:56,730 --> 00:16:59,300 And where was God? 219 00:17:01,230 --> 00:17:03,060 Everywhere. 220 00:17:03,200 --> 00:17:04,930 In the rocks and in the rivers, 221 00:17:05,060 --> 00:17:09,130 in the trees, in the birds and every living thing. 222 00:17:09,430 --> 00:17:11,400 And that was human nature for a couple of 223 00:17:11,530 --> 00:17:13,960 hundred thousand years. 224 00:17:14,400 --> 00:17:17,560 I'm standing on the southern tip of Africa and imagining 225 00:17:17,700 --> 00:17:19,960 what it was like some time in the last hundreds 226 00:17:20,100 --> 00:17:21,800 of thousands of years. 227 00:17:21,930 --> 00:17:26,160 Back then, Africa was home to all the world's homo sapiens... 228 00:17:27,430 --> 00:17:29,760 All 10,000 of them. 229 00:17:30,230 --> 00:17:33,200 If you were an extra-terrestrial on a survey mission, 230 00:17:33,330 --> 00:17:36,830 you might have thought we were an endangered species. 231 00:17:36,960 --> 00:17:40,860 Someday soon there will be ten billion of us. 232 00:17:41,000 --> 00:17:42,330 What happened? 233 00:17:42,460 --> 00:17:44,660 How did we become the globe-girdling, 234 00:17:44,800 --> 00:17:47,760 space-traveling species that we are today? 235 00:17:56,830 --> 00:18:00,300 Welcome to the first laboratory on Earth. 236 00:18:00,430 --> 00:18:03,300 We're in Blombos Cave where the evolution of the mind 237 00:18:03,430 --> 00:18:05,300 made a great leap. 238 00:18:05,430 --> 00:18:07,760 Our ancestors were conducting chemistry experiments 239 00:18:07,900 --> 00:18:11,860 here with a mineral rich in iron, ocher. 240 00:18:13,400 --> 00:18:16,530 They used it to decorate objects with bits of red color, 241 00:18:16,660 --> 00:18:19,100 but it may have also had other uses, 242 00:18:19,230 --> 00:18:21,030 to preserve animal hides or as a medicine, 243 00:18:22,200 --> 00:18:24,100 or as a way to sharpen their tools, 244 00:18:25,860 --> 00:18:28,330 or maybe as an insect repellent. 245 00:18:29,830 --> 00:18:32,100 And they engraved the ocher with symbols. 246 00:18:32,230 --> 00:18:36,000 Something completely new on the planet Earth, art. 247 00:18:37,630 --> 00:18:39,460 Not to be eaten. 248 00:18:39,600 --> 00:18:41,330 Not to provide shelter. 249 00:18:41,460 --> 00:18:44,060 But to symbolize something... 250 00:18:44,200 --> 00:18:46,360 Or just to be. 251 00:18:47,400 --> 00:18:48,900 It looks a little bit like a ladder, 252 00:18:49,030 --> 00:18:50,530 or a double helix. 253 00:18:50,660 --> 00:18:52,330 Whatever it was supposed to be, 254 00:18:52,460 --> 00:18:55,600 it's the earliest remnant we have of human culture. 255 00:18:56,000 --> 00:19:00,360 We had found a way to leave behind something distinctly human. 256 00:19:00,730 --> 00:19:04,130 A means to communicate, however enigmatically, 257 00:19:04,260 --> 00:19:08,600 to you and me 100,000 years away. 258 00:19:09,660 --> 00:19:12,630 A great power was discovered here in Blombos Cave. 259 00:19:20,430 --> 00:19:23,800 At 25 cosmic seconds-to-midnight, 260 00:19:23,930 --> 00:19:27,260 between 10,000 and 12,000 years ago, 261 00:19:28,000 --> 00:19:31,830 humans discovered another great power. 262 00:19:32,560 --> 00:19:35,000 Instead of foraging for food, 263 00:19:35,130 --> 00:19:37,730 we learned how to grow it in the earth. 264 00:19:39,130 --> 00:19:42,400 This changed everything. 265 00:19:42,830 --> 00:19:44,760 Our ancestors did something else they had 266 00:19:44,900 --> 00:19:46,630 never done before. 267 00:19:46,760 --> 00:19:49,160 They invented new tools, technology, 268 00:19:50,300 --> 00:19:53,330 to plant and pull food out of the earth. 269 00:19:54,030 --> 00:19:57,100 They settled down and moved indoors. 270 00:19:57,660 --> 00:20:00,600 Our relationship to nature, and to one another, 271 00:20:00,730 --> 00:20:03,300 would never be the same. 272 00:20:03,760 --> 00:20:06,160 This agricultural revolution, 273 00:20:06,300 --> 00:20:09,130 the domestication of plants and animals, 274 00:20:09,260 --> 00:20:12,430 is the mother of all revolutions because all 275 00:20:12,560 --> 00:20:14,830 others trace back to it. 276 00:20:14,960 --> 00:20:17,360 Its consequences reach far beyond even our 277 00:20:17,500 --> 00:20:19,830 own moment in time. 278 00:20:19,960 --> 00:20:21,800 Like most revolutions, 279 00:20:21,930 --> 00:20:24,860 this one brought change that was both great, 280 00:20:25,000 --> 00:20:26,600 and horrifying. 281 00:20:26,730 --> 00:20:30,530 There was a new concept in the world, "Home." 282 00:20:31,730 --> 00:20:34,860 A specific place on the planet where your ancestors, 283 00:20:35,000 --> 00:20:38,300 and you, were born and lived. 284 00:20:38,760 --> 00:20:41,630 And over time these settlements grew larger, 285 00:20:41,760 --> 00:20:47,360 until about 20 cosmic seconds ago or around 7000 BCE. 286 00:20:53,660 --> 00:20:56,100 Welcome to Çatalhöyük, 287 00:20:56,230 --> 00:20:58,730 a community on the Anatolian plain. 288 00:20:58,860 --> 00:21:01,960 It's about 9,000 years ago and everyone has settled 289 00:21:02,100 --> 00:21:04,200 in for the evening. 290 00:21:04,530 --> 00:21:07,530 Tonight, roughly the same number of people who once 291 00:21:07,660 --> 00:21:11,300 populated all of Africa are living together 292 00:21:11,430 --> 00:21:13,660 in this proto-city. 293 00:21:14,300 --> 00:21:16,800 The city is such a new idea, 294 00:21:16,930 --> 00:21:19,260 they haven't invented the street yet, 295 00:21:19,400 --> 00:21:21,060 or the window. 296 00:21:21,200 --> 00:21:23,900 So the only way you can get into your apartment is to walk 297 00:21:24,030 --> 00:21:26,930 along the rooftops till you arrive at the opening 298 00:21:27,060 --> 00:21:28,560 to your dwelling. 299 00:21:30,030 --> 00:21:32,960 Çatalhöyük lacked something much more significant than 300 00:21:33,100 --> 00:21:36,230 streets and windows. 301 00:21:36,860 --> 00:21:40,060 There is no palace here. 302 00:21:40,200 --> 00:21:42,760 The bitter price that the invention of agriculture cost 303 00:21:42,900 --> 00:21:45,960 human society had yet to be paid. 304 00:21:46,260 --> 00:21:50,100 Here, there was no dominance of the few over the many. 305 00:21:50,230 --> 00:21:53,600 There was no 1% attaining lavish wealth, 306 00:21:53,730 --> 00:21:56,800 while most everyone else merely subsisted. 307 00:21:56,930 --> 00:22:00,100 Forensic analysis of the women, men, and children 308 00:22:00,230 --> 00:22:03,600 who lived here show a remarkable similarity in diet. 309 00:22:04,960 --> 00:22:09,100 They still cherished the hunter-gatherer ethos of sharing. 310 00:22:09,730 --> 00:22:12,900 Çatalhöyük was egalitarian. 311 00:22:13,030 --> 00:22:16,160 The weakest ate the same food that the strongest did, 312 00:22:17,130 --> 00:22:20,330 and everyone lived in the same kind of home. 313 00:22:20,830 --> 00:22:23,330 But, man, it was anything but drab. 314 00:22:23,460 --> 00:22:26,230 Come on. I'll show you. 315 00:22:40,900 --> 00:22:44,300 This was a typical apartment in one of the first cities, 316 00:22:45,300 --> 00:22:47,560 Çatalhöyük, in what is now Turkey, 317 00:22:47,700 --> 00:22:50,330 as it looked about 9,000 years ago. 318 00:22:52,530 --> 00:22:55,200 They were a lot like us. 319 00:22:56,730 --> 00:22:59,160 This bit of volcanic glass, 320 00:22:59,300 --> 00:23:01,800 called obsidian, made an excellent mirror. 321 00:23:05,130 --> 00:23:08,530 If we could only find a way to see all the things 322 00:23:08,660 --> 00:23:10,530 that were once reflected here. 323 00:23:14,200 --> 00:23:16,230 This apartment was home for an extended family of 324 00:23:16,360 --> 00:23:18,400 seven to ten people. 325 00:23:18,530 --> 00:23:20,500 Every apartment had a similar floor plan. 326 00:23:21,700 --> 00:23:26,630 Bedroom. Living room. Kitchen. 327 00:23:29,700 --> 00:23:32,000 Plaster auroch head. 328 00:23:32,130 --> 00:23:35,730 The people of Çatalhöyük had a passion for decorating. 329 00:23:36,030 --> 00:23:38,830 Apartments were richly appointed with the teeth and 330 00:23:38,960 --> 00:23:41,160 bones and skins of animals. 331 00:23:42,230 --> 00:23:44,900 The ocher that our ancestors picked up in Africa, 332 00:23:45,030 --> 00:23:48,600 about 100,000 years before, was now the medium of choice 333 00:23:49,660 --> 00:23:52,400 for the interior decorators of Çatalhöyük. 334 00:23:57,260 --> 00:24:00,160 And the red ocher had yet another profound application. 335 00:24:01,230 --> 00:24:04,800 They used it to create an entirely new art form: 336 00:24:05,130 --> 00:24:06,660 the map. 337 00:24:06,800 --> 00:24:09,100 For the first time ever, humans created a 338 00:24:09,230 --> 00:24:12,300 two-dimensional representation of their location 339 00:24:12,430 --> 00:24:14,860 in space and time. 340 00:24:16,400 --> 00:24:20,560 "This is where my home is in relation to the volcano." 341 00:24:21,630 --> 00:24:23,600 And with a few magical strokes, 342 00:24:23,730 --> 00:24:26,860 the artist sent a message across 9,000 years... 343 00:24:27,760 --> 00:24:31,530 "I was here when the volcano awakened." 344 00:24:40,430 --> 00:24:43,430 The experiment at Çatalhöyük was a success, 345 00:24:43,560 --> 00:24:47,000 and within a few thousand years there were cities everywhere. 346 00:25:04,560 --> 00:25:06,730 When different kinds of people congregate 347 00:25:06,860 --> 00:25:08,060 in a single place, 348 00:25:08,200 --> 00:25:11,000 ideas are exchanged and new possibilities arise. 349 00:25:12,100 --> 00:25:14,400 The city is a kind of brain, 350 00:25:14,530 --> 00:25:16,960 creating and processing new ideas. 351 00:25:20,130 --> 00:25:22,200 Here, in the city of Amsterdam, 352 00:25:22,330 --> 00:25:24,760 in the 17th century, citizens of the old and 353 00:25:24,900 --> 00:25:27,560 new worlds mingled as they never had before, 354 00:25:28,500 --> 00:25:30,930 and there was an unprecedented freedom of thought. 355 00:25:31,860 --> 00:25:35,760 These conditions produced a golden age of science and art. 356 00:25:36,460 --> 00:25:39,560 In Italy, Giordano Bruno had proclaimed the existence 357 00:25:39,700 --> 00:25:41,160 of other worlds. 358 00:25:41,300 --> 00:25:44,830 For this he had been made to suffer. 359 00:25:45,860 --> 00:25:48,230 But a mere 50 years later in Holland, 360 00:25:48,360 --> 00:25:50,160 the astronomer Christiaan Huygens, 361 00:25:50,300 --> 00:25:53,530 who held the same belief, was showered with honors. 362 00:25:56,400 --> 00:26:00,130 Light was the central theme of the age: 363 00:26:00,530 --> 00:26:04,500 The enlightenment of human curiosity set free, 364 00:26:04,830 --> 00:26:07,260 and the light shed by Europe's first look at 365 00:26:07,400 --> 00:26:10,130 the once hidden realms of the planet. 366 00:26:10,900 --> 00:26:14,060 The light that permeated the paintings of the time, 367 00:26:14,200 --> 00:26:16,900 particularly the work of Vermeer. 368 00:26:18,200 --> 00:26:21,500 And light as an object of scientific inquiry. 369 00:26:22,700 --> 00:26:25,860 For generations, textile merchants had used a lens to 370 00:26:26,000 --> 00:26:28,400 examine the thread count of finely stitched fabrics. 371 00:26:29,530 --> 00:26:31,360 In the Amsterdam of that time, 372 00:26:31,500 --> 00:26:33,460 there lived three men whose passion for 373 00:26:33,600 --> 00:26:37,960 light inspired them to use that ancient device in a completely new way. 374 00:26:39,360 --> 00:26:42,460 They aimed the textile merchants' lens at objects no 375 00:26:42,600 --> 00:26:45,730 one had ever thought to examine closely before. 376 00:26:46,200 --> 00:26:49,260 It became a window, an aperture for finding and 377 00:26:49,400 --> 00:26:51,860 exploring new worlds. 378 00:26:52,260 --> 00:26:55,630 Antonie Van Leeuwenhoek used a single lens to reveal 379 00:26:55,760 --> 00:26:58,530 the teeming microcosm in a drop of water. 380 00:27:06,400 --> 00:27:07,700 His friend, 381 00:27:07,830 --> 00:27:10,330 Christiaan Huygens used two lenses to bring the stars, 382 00:27:10,460 --> 00:27:13,130 planets, and moons close enough to 383 00:27:13,260 --> 00:27:15,230 reveal their features. 384 00:27:15,960 --> 00:27:19,130 Huygens became the first to see that Saturn's rings did not 385 00:27:19,260 --> 00:27:23,500 touch the planet, and the first to understand what they really were. 386 00:27:25,160 --> 00:27:28,060 He also discovered Saturn's largest moon, Titan. 387 00:27:29,560 --> 00:27:31,130 Huygens, like Bruno, 388 00:27:31,260 --> 00:27:33,860 believed that the stars were other suns, 389 00:27:34,000 --> 00:27:37,260 orbited by their own systems of planets and moons. 390 00:27:37,900 --> 00:27:40,200 But why was there no hint of those other worlds and 391 00:27:40,330 --> 00:27:44,430 their living things in the sacred books? 392 00:27:45,930 --> 00:27:48,630 Whatever disquiet this contradiction may have stirred 393 00:27:48,760 --> 00:27:52,000 in the hearts and minds of the leaders of the Enlightenment, 394 00:27:52,130 --> 00:27:55,660 there was only one man who dared to address it head-on. 395 00:27:56,000 --> 00:27:58,760 He was another wizard of light. 396 00:27:58,900 --> 00:28:01,330 Baruch Spinoza had been a member of the Jewish 397 00:28:01,460 --> 00:28:04,000 congregation of Amsterdam through his teenage years. 398 00:28:05,160 --> 00:28:07,860 But in his early 20s, he began to speak publicly of 399 00:28:08,000 --> 00:28:10,300 a new vision of God. 400 00:28:11,660 --> 00:28:14,630 Spinoza's God was the physical laws of the universe. 401 00:28:16,500 --> 00:28:19,630 His sacred text, the book of nature. 402 00:28:22,360 --> 00:28:24,560 The Jews of Amsterdam were mostly refugees from 403 00:28:24,700 --> 00:28:27,630 the vicious Inquisitions in Spain and Portugal, 404 00:28:28,000 --> 00:28:30,900 where so many of them had been tortured and murdered. 405 00:28:32,900 --> 00:28:35,900 Amsterdam had offered the Jews a refuge, 406 00:28:36,030 --> 00:28:38,400 and they must have seen Spinoza's radical ideas as a 407 00:28:38,530 --> 00:28:41,560 threat to their hard-won security in Holland. 408 00:28:42,230 --> 00:28:44,130 They excommunicated the young rebel, 409 00:28:44,260 --> 00:28:46,860 and decreed that he must be forever shunned. 410 00:28:47,530 --> 00:28:50,730 Spinoza accepted their punishment with dignity, 411 00:28:50,860 --> 00:28:53,400 but without a trace of submission. 412 00:28:53,530 --> 00:28:55,500 He moved nearby, to The Hague. 413 00:28:55,630 --> 00:28:58,900 Where he went even further, daring to write that the Bible 414 00:28:59,030 --> 00:29:02,830 was not dictated by God, but written by human beings. 415 00:29:03,330 --> 00:29:04,760 Spinoza wrote: 416 00:29:04,900 --> 00:29:07,100 "Do not look for God in miracles." 417 00:29:07,230 --> 00:29:10,100 Miracles are violations of the laws of nature. 418 00:29:10,630 --> 00:29:13,630 "God is best apprehended in the study of those laws." 419 00:29:15,460 --> 00:29:18,230 No one had ever said these things aloud before. 420 00:29:18,800 --> 00:29:22,200 Spinoza knew that he was testing the limits of free thought, 421 00:29:22,330 --> 00:29:24,360 even for Holland. 422 00:29:27,500 --> 00:29:30,860 To him, an official state religion was more than 423 00:29:31,000 --> 00:29:34,160 spiritual coercion of the individual. 424 00:29:34,300 --> 00:29:37,500 Spinoza regarded the miraculous events of the major 425 00:29:37,630 --> 00:29:40,900 religious traditions as organized superstition. 426 00:29:42,400 --> 00:29:45,960 In his view, magical thinking posed a danger to 427 00:29:46,100 --> 00:29:49,860 the future citizens of a rational, free society. 428 00:29:51,000 --> 00:29:53,600 There could be no such thing as democracy without the 429 00:29:53,730 --> 00:29:56,430 separation of church and state. 430 00:29:56,560 --> 00:29:59,300 He wrote a book that introduced the ideas at the 431 00:29:59,430 --> 00:30:02,800 heart of the American and many another revolution. 432 00:30:04,800 --> 00:30:07,730 Then, as now, there were those who were threatened 433 00:30:07,860 --> 00:30:09,830 by this view of God. 434 00:30:20,960 --> 00:30:23,500 Spinoza continued to write and speak about his 435 00:30:23,630 --> 00:30:26,130 revolutionary view of God, 436 00:30:26,260 --> 00:30:29,100 always wearing the slashed cape as a badge of honor. 437 00:30:31,300 --> 00:30:35,260 He died at 44, possibly from inhaling particles of dust 438 00:30:35,400 --> 00:30:37,330 during his years of grinding lenses for 439 00:30:37,460 --> 00:30:39,630 microscopes and telescopes. 440 00:30:40,930 --> 00:30:44,800 250 years later, another man with a passion for light made 441 00:30:44,930 --> 00:30:47,400 a pilgrimage to the humble workroom that had been 442 00:30:47,530 --> 00:30:50,130 preserved as a testament to the vast influence of 443 00:30:50,260 --> 00:30:52,300 Spinoza's philosophy. 444 00:30:52,430 --> 00:30:56,160 This man, world famous for finding a new law of nature, 445 00:30:56,300 --> 00:30:59,500 was often asked if he believed in God. 446 00:30:59,630 --> 00:31:01,630 Albert Einstein replied: 447 00:31:02,230 --> 00:31:08,300 "I believe in Spinoza's God, who reveals himself in the harmony of all that exists." 448 00:31:12,230 --> 00:31:15,500 Our understanding of nature's laws has advanced far beyond 449 00:31:15,630 --> 00:31:18,660 Spinoza's, and even Einstein's wildest dreams. 450 00:31:19,960 --> 00:31:23,600 But there is one law of nature we cannot seem to grasp. 451 00:31:24,200 --> 00:31:27,030 Inscribed in the book of nature is a parable about an 452 00:31:27,160 --> 00:31:29,800 ancient alliance between two kingdoms. 453 00:31:30,530 --> 00:31:33,660 And those who would tear it apart. 454 00:31:46,330 --> 00:31:48,960 Long ago, there were two kingdoms. 455 00:31:49,100 --> 00:31:51,400 An alliance was formed between them, 456 00:31:51,530 --> 00:31:54,530 one that would bring them both riches beyond measure. 457 00:31:55,200 --> 00:31:59,400 A partnership lasting more than a 100 million years. 458 00:31:59,530 --> 00:32:03,700 And then a new kind of being evolved in one of the two kingdoms. 459 00:32:04,230 --> 00:32:08,830 Its descendants plundered the riches and violated the alliance. 460 00:32:09,200 --> 00:32:12,560 In their arrogance, they became a mortal danger to both 461 00:32:12,700 --> 00:32:15,500 kingdoms and to themselves. 462 00:32:27,160 --> 00:32:29,430 This parable is true. 463 00:32:29,560 --> 00:32:33,260 It's the story of two of the half dozen realms of life on Earth, 464 00:32:33,400 --> 00:32:36,460 the plant and animal kingdoms. 465 00:32:37,160 --> 00:32:39,960 It's not easy being green. 466 00:32:41,130 --> 00:32:44,600 Sex is challenging when you're stuck in one place. 467 00:32:44,730 --> 00:32:46,000 There's no dating. 468 00:32:46,130 --> 00:32:49,030 You just sit there and cast your seed to the winds. 469 00:32:50,200 --> 00:32:51,630 Literally. 470 00:32:51,760 --> 00:32:54,200 You just wait for the wind to blow. 471 00:32:54,330 --> 00:32:56,460 If you get lucky, some of your pollen will 472 00:32:56,600 --> 00:32:59,500 be carried away and land on the sexual reproductive part 473 00:32:59,630 --> 00:33:02,060 of another plant. 474 00:33:02,200 --> 00:33:04,600 The plants played this hit-or-miss game of chance for 475 00:33:04,730 --> 00:33:06,960 a couple of hundred million years, 476 00:33:07,100 --> 00:33:10,830 until insects evolved to play cupid. 477 00:33:15,000 --> 00:33:17,800 What resulted was one of the great co-evolution marriages 478 00:33:17,930 --> 00:33:19,800 in the history of life. 479 00:33:19,930 --> 00:33:22,330 The insect would visit a flower for a dinner of 480 00:33:22,460 --> 00:33:24,660 protein-rich pollen. 481 00:33:24,800 --> 00:33:27,630 Inevitably, some of the pollen would stick to the body 482 00:33:27,760 --> 00:33:29,460 of the insect. 483 00:33:29,600 --> 00:33:31,500 The insect would visit another flower, 484 00:33:31,630 --> 00:33:34,360 bringing along the leftovers on its body. 485 00:33:34,930 --> 00:33:37,960 That pollen fertilized the next flower, 486 00:33:38,100 --> 00:33:40,330 allowing it to reproduce. 487 00:33:41,230 --> 00:33:44,460 It was a win-win deal for both the flowers and the insects, 488 00:33:45,300 --> 00:33:48,000 causing a series of delightful evolutionary developments. 489 00:33:49,230 --> 00:33:52,100 A new plant arose that produced sugary nectar in 490 00:33:52,230 --> 00:33:54,030 addition to the pollen. 491 00:33:54,160 --> 00:33:58,000 Now, the insects came not just for their basic meal of pollen, 492 00:33:58,660 --> 00:34:01,060 but also for dessert. 493 00:34:01,660 --> 00:34:05,160 The insects got chubbier, evolved furry bodies and even 494 00:34:05,300 --> 00:34:08,400 little pouches on their legs to snag more pollen on their 495 00:34:08,530 --> 00:34:10,760 daily rounds in the flowers. 496 00:34:13,060 --> 00:34:15,300 Now there were bees. 497 00:34:16,430 --> 00:34:18,530 This was a bonus for yet another species of 498 00:34:18,660 --> 00:34:20,360 the animal kingdom... 499 00:34:20,500 --> 00:34:22,300 Us. 500 00:34:25,730 --> 00:34:28,560 We are indebted to the bees and their fellow pollinators 501 00:34:28,700 --> 00:34:32,000 for something even more vital to our survival. 502 00:34:32,300 --> 00:34:35,700 Every third bite of food you take-and this is even true for 503 00:34:35,830 --> 00:34:39,630 those of us who are omnivores, was made possible by them. 504 00:34:40,460 --> 00:34:44,000 35% of the world's crops depend on their cooperation. 505 00:34:44,860 --> 00:34:47,100 The plants eat starlight... 506 00:34:47,230 --> 00:34:50,560 And we, and the animals, we eat plants. 507 00:34:51,600 --> 00:34:54,730 And they don't just increase the quantity of available food. 508 00:34:54,860 --> 00:34:57,760 We owe them for much of the biodiversity that has made our 509 00:34:57,900 --> 00:35:01,200 food supply so dependable. 510 00:35:01,330 --> 00:35:03,700 But we're working them to death. 511 00:35:03,830 --> 00:35:05,400 And for the first time ever, 512 00:35:05,530 --> 00:35:10,060 many kinds of bees are on the endangered species list. 513 00:35:22,060 --> 00:35:25,000 I think you know where this is headed. 514 00:35:34,300 --> 00:35:37,900 The blessing and the curse of the invention of agriculture 515 00:35:38,030 --> 00:35:40,460 has brought us here, to the Halls of Extinction. 516 00:35:51,130 --> 00:35:55,330 A memorial to all the living things lost in the mass 517 00:35:55,460 --> 00:35:58,030 extinction events in Earth's history. 518 00:35:58,930 --> 00:36:03,600 It's a monument to the broken branches on the tree of life. 519 00:36:04,630 --> 00:36:07,500 Five times in the history of life, 520 00:36:07,630 --> 00:36:11,130 cataclysmic geological, and astronomical events, 521 00:36:11,260 --> 00:36:15,860 have threatened to extinguish life itself. 522 00:36:17,530 --> 00:36:20,860 The sixth one is different. 523 00:36:21,130 --> 00:36:24,260 The last time we were here together this hallway 524 00:36:24,400 --> 00:36:26,000 had no name. 525 00:36:26,130 --> 00:36:27,330 Why? 526 00:36:27,460 --> 00:36:30,000 Because back then a scientific consensus had yet 527 00:36:30,130 --> 00:36:34,530 to be reached that we were in the midst of a mass extinction event. 528 00:36:35,260 --> 00:36:36,800 That's changed. 529 00:36:36,930 --> 00:36:40,100 Now, this hallway has a name. 530 00:36:40,800 --> 00:36:42,860 It's ours. 531 00:36:43,000 --> 00:36:46,060 The Anthropocene. 532 00:36:47,400 --> 00:36:52,630 "Anthropo" from the Greek word for "human" and "Cene." 533 00:36:54,200 --> 00:36:56,900 the Greek word for "recent." 534 00:37:14,330 --> 00:37:17,100 These are the species we hunted to extinction back 535 00:37:17,230 --> 00:37:19,630 when we were wanderers. 536 00:37:19,900 --> 00:37:23,360 Including our own cousins, the Neanderthals. 537 00:37:38,860 --> 00:37:41,200 What is it about us, as a species, 538 00:37:41,330 --> 00:37:45,130 that wherever we go, we bring death? 539 00:37:49,230 --> 00:37:52,330 Beyond here lies the future. 540 00:37:52,460 --> 00:37:56,360 Even now it's not too late to keep this corridor from lengthening. 541 00:37:58,460 --> 00:38:01,260 If we fail... 542 00:38:12,600 --> 00:38:15,230 But if we succeed... 543 00:38:15,560 --> 00:38:17,330 Come with me. 544 00:38:30,830 --> 00:38:34,400 In a possible future only decades away, 545 00:38:34,530 --> 00:38:38,930 project Starshot, a flotilla of 1,000 spacecraft, 546 00:38:39,060 --> 00:38:41,230 will depart from Earth. 547 00:38:41,360 --> 00:38:44,460 This part of the Atacama Desert west of the Andes Mountains, 548 00:38:44,600 --> 00:38:47,930 is so dry that it hasn't rained in recorded history. 549 00:38:49,360 --> 00:38:52,400 And that's great for us because we're going to need 550 00:38:52,530 --> 00:38:54,360 the clearest of skies. 551 00:39:26,560 --> 00:39:29,060 There were no witnesses when the first life left the 552 00:39:29,200 --> 00:39:32,100 water for the land. 553 00:39:32,400 --> 00:39:34,960 There was nobody to file a report when the first birds 554 00:39:35,100 --> 00:39:37,360 took to the skies. 555 00:39:37,500 --> 00:39:40,030 But this is one great leap that will be documented in 556 00:39:40,160 --> 00:39:42,600 every conceivable way. 557 00:39:42,730 --> 00:39:45,260 The whole world is watching. 558 00:39:46,160 --> 00:39:49,160 We are, after all, sending our first craft directly to the 559 00:39:49,300 --> 00:39:52,900 planets of another sun: the Alpha Centauri system. 560 00:39:56,300 --> 00:39:59,660 These are the ships that will carry our senses there. 561 00:39:59,800 --> 00:40:03,500 These are interstellar sailing ships propelled by light. 562 00:40:04,130 --> 00:40:07,700 Their hulls weigh but a gram, and they are no larger than a 563 00:40:07,830 --> 00:40:11,360 pea, and yet they're equipped with all that NASA's Voyagers 564 00:40:11,500 --> 00:40:13,630 have and more. 565 00:40:23,160 --> 00:40:26,160 When the first light blasts forth from this phased array 566 00:40:26,300 --> 00:40:30,530 of lasers, the spacecraft will accelerate from zero to 20% of 567 00:40:30,660 --> 00:40:34,200 the speed of light in mere minutes. 568 00:40:34,460 --> 00:40:37,400 Inside each nanocraft is everything needed to perform 569 00:40:37,530 --> 00:40:41,400 the preliminary reconnaissance of the worlds of another star 570 00:40:41,530 --> 00:40:44,560 and return that visual and scientific information 571 00:40:44,700 --> 00:40:46,800 back to Earth. 572 00:40:48,160 --> 00:40:50,530 Space is mostly empty, 573 00:40:50,660 --> 00:40:52,600 but there are tiny dust particles that could 574 00:40:52,730 --> 00:40:55,460 wreak havoc if they were to collide with nanocraft 575 00:40:55,600 --> 00:40:57,460 traveling at such high speeds. 576 00:41:08,800 --> 00:41:11,230 That's one of the reasons we need to send so many of them. 577 00:41:17,960 --> 00:41:21,600 Voyager 1 is traveling at 38,000 miles per hour. 578 00:41:22,660 --> 00:41:25,760 It left home more than 40 years ago. 579 00:41:27,060 --> 00:41:29,700 It will take these nanocraft only four days 580 00:41:29,830 --> 00:41:31,400 to overtake her. 581 00:41:31,530 --> 00:41:33,030 That's pretty fast, 582 00:41:33,160 --> 00:41:36,060 but still only 20% of the speed of light. 583 00:41:36,200 --> 00:41:39,300 Proxima Centauri is four light-years away. 584 00:41:39,430 --> 00:41:41,600 That's a 20 year one-way trip. 585 00:41:44,560 --> 00:41:47,100 Orbiting Proxima Centauri, there is a world in the 586 00:41:47,230 --> 00:41:50,930 habitable zone where we think life might flourish. 587 00:41:53,930 --> 00:41:56,330 Our robotic emissaries will send accounts from 588 00:41:56,460 --> 00:41:59,160 these new worlds. 589 00:41:59,460 --> 00:42:02,030 Their messages will race back to us on radio waves 590 00:42:02,160 --> 00:42:03,960 at the speed of light. 591 00:42:04,100 --> 00:42:07,660 They'll take four years to reach us: 20 years one-way, 592 00:42:08,360 --> 00:42:10,230 four years back. 593 00:42:10,360 --> 00:42:13,360 That's a 24-year round-trip. 594 00:42:13,730 --> 00:42:18,260 Many of you will be there then to read and to write those new 595 00:42:18,400 --> 00:42:20,700 pages in the book of nature, 596 00:42:20,830 --> 00:42:23,760 and to chart our future course of wandering... 597 00:42:47,430 --> 00:42:49,830 No longer bounded by the earth, 598 00:42:49,960 --> 00:42:52,560 the ocean, 599 00:42:52,700 --> 00:42:55,430 or the sky. 600 00:43:14,130 --> 00:43:15,960 Captioned by Cotter Captioning Services.