1 00:00:02,711 --> 00:00:08,434 SAGAN: The cosmos is all that is, or ever was or ever will be. 2 00:00:10,135 --> 00:00:12,388 Come with me. 3 00:00:13,263 --> 00:00:16,688 TYSON: A generation ago, the astronomer Carl Sagan stood here... 4 00:00:16,850 --> 00:00:20,946 ...and launched hundreds of millions of us on a great adventure. 5 00:00:21,104 --> 00:00:25,234 The exploration of the universe revealed by science. 6 00:00:25,400 --> 00:00:27,528 It's time to get going again. 7 00:00:28,904 --> 00:00:31,248 We're about to begin a journey that will take us... 8 00:00:31,406 --> 00:00:33,750 ...from the infinitesimal to the infinite... 9 00:00:33,909 --> 00:00:36,628 ...from the dawn of time to the distant future. 10 00:00:36,787 --> 00:00:40,462 We'll explore galaxies and suns and worlds... 11 00:00:40,624 --> 00:00:43,969 ...surf the gravity waves of space-time... 12 00:00:44,127 --> 00:00:47,381 ...encounter beings that live in fire and ice... 13 00:00:47,548 --> 00:00:51,143 ...explore the planets of stars that never die... 14 00:00:51,301 --> 00:00:53,770 ...discover atoms as massive as suns... 15 00:00:53,929 --> 00:00:57,524 ...and universes smaller than atoms. 16 00:00:57,975 --> 00:01:01,070 Cosmos is also a story about us. 17 00:01:01,687 --> 00:01:05,157 It's the saga of how wandering bands of hunters and gatherers... 18 00:01:05,315 --> 00:01:08,990 ...found their way to the stars. 19 00:01:10,070 --> 00:01:13,665 One adventure with many heroes. 20 00:01:23,208 --> 00:01:26,178 To make this journey, we'll need imagination. 21 00:01:26,336 --> 00:01:28,384 But imagination alone is not enough... 22 00:01:28,547 --> 00:01:31,676 ...because the reality of nature is far more wondrous... 23 00:01:31,842 --> 00:01:33,810 ...than anything we can imagine. 24 00:01:37,973 --> 00:01:41,603 This adventure is made possible by generations of searchers... 25 00:01:41,768 --> 00:01:45,523 ...strictly adhering to a simple set of rules: 26 00:01:45,689 --> 00:01:49,364 Test ideas by experiment and observation. 27 00:01:49,526 --> 00:01:54,498 Build on those ideas that pass the test. Reject the ones that fail. 28 00:01:54,656 --> 00:01:57,205 Follow the evidence wherever it leads... 29 00:01:57,367 --> 00:01:59,745 ...and question everything. 30 00:01:59,911 --> 00:02:05,463 Accept these terms, and the cosmos is yours. 31 00:02:06,543 --> 00:02:10,264 Now come with me. 32 00:03:47,776 --> 00:03:49,276 "Standing Up in the Milky Way" 33 00:04:04,286 --> 00:04:06,254 In this ship of the imagination... 34 00:04:06,413 --> 00:04:11,761 ...free from the shackles of space and time, we can go anywhere. 35 00:04:11,918 --> 00:04:17,015 If you want to see where we are in space, just look out the front window. 36 00:04:21,303 --> 00:04:25,854 In the dimension of time, the past lies beneath us. 37 00:04:27,017 --> 00:04:31,944 Here is what Earth looked like 250 million years ago. 38 00:04:35,025 --> 00:04:38,199 If you wanna see the future, look up. 39 00:04:38,361 --> 00:04:43,618 And this is how it could appear 250 million years from now. 40 00:04:44,367 --> 00:04:48,463 If we're going to be venturing out into the farthest reaches of the cosmos... 41 00:04:48,622 --> 00:04:51,501 ...we need to know our cosmic address. 42 00:04:51,666 --> 00:04:55,170 And this is the first line of that address. 43 00:05:17,067 --> 00:05:20,742 We're leaving the Earth, the only home we've ever known... 44 00:05:20,904 --> 00:05:25,080 ...for the farthest reaches of the cosmos. 45 00:05:29,246 --> 00:05:33,046 Our nearest neighbor, the moon, has no sky... 46 00:05:33,959 --> 00:05:37,008 ...no ocean, no life. 47 00:05:37,170 --> 00:05:40,800 Just the scars of cosmic impacts. 48 00:05:53,436 --> 00:05:56,235 Our star powers the wind and the waves... 49 00:05:56,398 --> 00:05:59,698 ...and all the life on the surface of our world. 50 00:05:59,860 --> 00:06:02,363 The sun holds all the worlds of the solar system... 51 00:06:02,529 --> 00:06:06,875 ...in its gravitational embrace, starting with Mercury... 52 00:06:25,844 --> 00:06:29,940 ...to cloud-covered Venus, where runaway greenhouse effect... 53 00:06:30,098 --> 00:06:33,523 ...has turned it into a kind of hell. 54 00:06:39,357 --> 00:06:40,825 Mars. 55 00:06:40,984 --> 00:06:45,660 A world with as much land as Earth itself. 56 00:06:58,585 --> 00:07:04,843 A belt of rocky asteroids circles the sun between the orbits of Mars and Jupiter. 57 00:07:16,102 --> 00:07:19,652 With its four giant moons and dozens of smaller ones... 58 00:07:19,814 --> 00:07:23,193 ...Jupiter is like its own little solar system. 59 00:07:23,360 --> 00:07:27,740 It has more mass than all the other planets combined. 60 00:07:37,707 --> 00:07:40,756 Jupiter's Great Red Spot. 61 00:07:41,211 --> 00:07:44,715 A hurricane three times the size of our whole planet... 62 00:07:44,881 --> 00:07:47,885 ...that's been raging for centuries. 63 00:08:08,655 --> 00:08:12,410 The crown jewel of our solar system, Saturn... 64 00:08:12,575 --> 00:08:15,419 ...ringed by freeways of countless orbiting... 65 00:08:15,578 --> 00:08:18,081 ...and slowly tumbling snowballs. 66 00:08:18,248 --> 00:08:21,843 Every snowball, a little moon. 67 00:08:53,283 --> 00:08:54,785 Uranus... 68 00:08:56,911 --> 00:08:58,959 ...and Neptune. 69 00:08:59,122 --> 00:09:00,795 The outermost planets... 70 00:09:00,957 --> 00:09:04,012 ...unknown to the ancients and only discovered 71 00:09:04,024 --> 00:09:07,090 after the invention of the telescope. 72 00:09:08,840 --> 00:09:10,763 Beyond the outermost planet... 73 00:09:10,925 --> 00:09:15,305 ...there's a swarm of tens of thousands of frozen worlds. 74 00:09:32,822 --> 00:09:36,167 And Pluto is one of them. 75 00:09:48,880 --> 00:09:50,848 Of all our spacecraft... 76 00:09:51,007 --> 00:09:54,307 ...this is the one that's traveled farthest from home. 77 00:09:54,844 --> 00:09:56,812 Voyager 1. 78 00:09:58,348 --> 00:10:02,273 She bears a message to a billion years from now... 79 00:10:02,435 --> 00:10:05,063 ...something of who we were... 80 00:10:05,230 --> 00:10:08,450 ...how we felt and the music we made. 81 00:10:08,608 --> 00:10:10,702 [BLIND WILLIE JOHNSON'S "DARK WAS THE NIGHT" PLAYING] 82 00:10:20,787 --> 00:10:23,882 TYSON: The deeper waters of this vast cosmic ocean... 83 00:10:24,040 --> 00:10:27,886 ...and their numberless worlds lie ahead. 84 00:10:40,890 --> 00:10:44,190 From out here, the sun may look like just another star. 85 00:10:44,894 --> 00:10:49,024 But it still exerts its gravitational hold on a trillion frozen comets... 86 00:10:49,190 --> 00:10:51,943 "leftovers from the formation of the solar system... 87 00:10:52,110 --> 00:10:55,080 ...nearly five billion years ago. 88 00:10:55,238 --> 00:10:57,491 It's called the Oort Cloud. 89 00:10:57,657 --> 00:11:00,331 No one has ever seen it before, nor could they... 90 00:11:00,493 --> 00:11:02,587 ...because each one of these little worlds... 91 00:11:02,745 --> 00:11:07,546 ...is as far from its nearest neighbor as Earth is from Saturn. 92 00:11:08,251 --> 00:11:12,472 This enormous cloud of comets encloses the solar system... 93 00:11:12,630 --> 00:11:15,258 ...which is the second line of our cosmic address. 94 00:11:21,764 --> 00:11:26,270 We've only been able to detect the planets of other stars for a few decades... 95 00:11:26,436 --> 00:11:30,157 ...but we already know that planets are plentiful. 96 00:11:30,315 --> 00:11:33,114 They outnumber the stars. 97 00:11:33,276 --> 00:11:36,450 Almost all of them will be very different from Earth... 98 00:11:36,613 --> 00:11:38,957 ...and hostile to life as we know it. 99 00:11:39,115 --> 00:11:41,459 But what do we know about life? 100 00:11:41,618 --> 00:11:46,124 We've met only one kind so far: Earth life. 101 00:11:46,289 --> 00:11:49,668 See anything? Just empty space, right? 102 00:11:50,293 --> 00:11:54,264 Human eyes see only a sliver of the light that shines in the cosmos. 103 00:11:54,422 --> 00:11:59,303 But science gives us the power to see what our senses cannot. 104 00:11:59,469 --> 00:12:03,565 Infrared is the kind of light made visible by night-vision goggles. 105 00:12:03,723 --> 00:12:07,227 Throw an infrared sensor across the darkness. 106 00:12:07,393 --> 00:12:09,191 Rogue planet. 107 00:12:09,354 --> 00:12:11,823 World without a sun. 108 00:12:13,650 --> 00:12:18,076 Our galaxy has billions of them, adrift in perpetual night. 109 00:12:18,238 --> 00:12:21,538 They're orphans, cast away from their mother stars... 110 00:12:21,699 --> 00:12:24,794 ...during the chaotic birth of their native star systems. 111 00:12:27,247 --> 00:12:31,377 Rogue planets are molten at the core but frozen at the surface. 112 00:12:31,542 --> 00:12:33,465 There may be oceans of liquid water... 113 00:12:33,628 --> 00:12:36,632 ...in the zone between those extremes. 114 00:12:40,802 --> 00:12:44,682 Who knows what might be swimming there? 115 00:12:49,644 --> 00:12:52,568 This is what the Milky Way looks like in infrared. 116 00:12:52,730 --> 00:12:57,361 Every single dot, not just the bright ones, is a star. 117 00:12:58,111 --> 00:13:00,034 How many stars? 118 00:13:00,196 --> 00:13:01,869 How many worlds? 119 00:13:02,031 --> 00:13:04,033 How many ways of being alive? 120 00:13:05,535 --> 00:13:09,915 Where are we in this picture? See that trailing outer arm? 121 00:13:10,081 --> 00:13:11,708 That's where we live. 122 00:13:11,874 --> 00:13:14,844 About 30,000 light-years from the center. 123 00:13:15,003 --> 00:13:19,884 The Milky Way Galaxy is the next line of our cosmic address. 124 00:13:20,049 --> 00:13:23,178 We're now a hundred thousand light-years from home. 125 00:13:23,344 --> 00:13:26,097 It would take light, the fastest thing there is... 126 00:13:26,264 --> 00:13:29,643 ...a hundred thousand years to reach us from Earth. 127 00:13:32,520 --> 00:13:37,492 This is the great spiral in Andromeda. The galaxy next door. 128 00:13:37,650 --> 00:13:41,029 We call our two giant galaxies and a smattering of smaller ones... 129 00:13:41,195 --> 00:13:43,243 ...the Local Group. 130 00:13:51,247 --> 00:13:54,592 Can't even find our home galaxy from out here. 131 00:13:54,751 --> 00:13:58,847 It's just one of thousands in the Virgo Supercluster. 132 00:13:59,547 --> 00:14:04,394 On this scale, all the objects we see, including the tiniest dots... 133 00:14:04,552 --> 00:14:05,724 ...are galaxies. 134 00:14:05,887 --> 00:14:10,563 Each galaxy contains billions of suns and countless worlds. 135 00:14:10,725 --> 00:14:14,355 Yet, the entire Virgo Supercluster itself... 136 00:14:14,520 --> 00:14:18,115 ...forms but a tiny part of our universe. 137 00:14:19,275 --> 00:14:23,075 This is the cosmos on the grandest scale we know... 138 00:14:23,237 --> 00:14:26,537 ...a network of a hundred billion galaxies. 139 00:14:26,699 --> 00:14:30,795 It's the last line of our cosmic address. For now. 140 00:14:33,581 --> 00:14:36,881 Observable universe? What does that mean? 141 00:14:37,043 --> 00:14:39,637 Even for us, in our ship of the imagination... 142 00:14:39,796 --> 00:14:43,346 ...there's a limit to how far we can see in space-time. 143 00:14:43,508 --> 00:14:45,806 It's our cosmic horizon. 144 00:14:45,968 --> 00:14:51,020 Beyond that horizon lie parts of the universe that are too far away. 145 00:14:51,182 --> 00:14:52,900 There hasn't been enough time... 146 00:14:53,059 --> 00:14:56,313 ...in the 13.8 billion year history of the universe... 147 00:14:56,479 --> 00:14:58,573 ...for their light to have reached us. 148 00:15:01,109 --> 00:15:04,079 Many of us suspect that all of this... 149 00:15:04,237 --> 00:15:08,287 ...all the worlds, stars, galaxies and clusters... 150 00:15:08,449 --> 00:15:10,793 ...in our observable universe... 151 00:15:10,952 --> 00:15:17,927 ...is but one tiny bubble in an infinite ocean of other universes. 152 00:15:19,252 --> 00:15:21,505 A multiverse. 153 00:15:22,088 --> 00:15:25,137 Universe upon universe. 154 00:15:25,550 --> 00:15:28,474 Worlds without end. 155 00:15:33,224 --> 00:15:34,692 Feeling a little small? 156 00:15:34,851 --> 00:15:38,526 Well, in the context of the cosmos, we are small. 157 00:15:38,980 --> 00:15:41,574 We may just be little guys living on a speck of dust... 158 00:15:41,732 --> 00:15:44,485 ...afloat in a staggering immensity... 159 00:15:44,652 --> 00:15:46,620 ...but we don't think small. 160 00:15:46,779 --> 00:15:49,658 This cosmic perspective is relatively new. 161 00:15:49,824 --> 00:15:53,954 A mere four centuries ago, our tiny world was oblivious... 162 00:15:54,120 --> 00:15:55,997 ...to the rest of the cosmos. 163 00:15:56,164 --> 00:15:57,757 There were no telescopes. 164 00:15:57,915 --> 00:16:01,761 The universe was only what you could see with the naked eye. 165 00:16:01,919 --> 00:16:07,301 Back in 1599, everyone knew that the sun, planets and stars... 166 00:16:07,467 --> 00:16:11,347 ...were just lights in the sky that revolved around the Earth... 167 00:16:11,512 --> 00:16:15,233 ...and that we were the center of a little universe. 168 00:16:15,391 --> 00:16:18,986 A universe made for us. 169 00:16:19,645 --> 00:16:21,989 There was only one man on the whole planet... 170 00:16:22,148 --> 00:16:25,072 ...who envisioned an infinitely grander cosmos. 171 00:16:25,234 --> 00:16:27,453 And how was he spending New Year's Eve... 172 00:16:27,612 --> 00:16:30,115 ...of the year 1600? 173 00:16:30,823 --> 00:16:33,793 Why, in prison, of course. 174 00:16:42,168 --> 00:16:44,785 There comes a time in our lives when we first 175 00:16:44,797 --> 00:16:47,425 realize we're not the center of the universe... 176 00:16:47,924 --> 00:16:51,144 ...that we belong to something much greater than ourselves. 177 00:16:51,302 --> 00:16:53,145 It's part of growing up. 178 00:16:53,304 --> 00:16:57,901 And as it happens to each of us, so it began to happen to our civilization... 179 00:16:58,059 --> 00:17:00,027 ...in the 16th century. 180 00:17:00,186 --> 00:17:02,109 Imagine a world before telescopes... 181 00:17:02,271 --> 00:17:05,400 ...when the universe was only what you could see with the naked eye. 182 00:17:05,566 --> 00:17:08,490 It was obvious that Earth was motionless... 183 00:17:08,653 --> 00:17:12,658 ...and that everything in the heavens, the sun, the moon, the stars, the planets... 184 00:17:12,823 --> 00:17:14,325 ...revolved around us. 185 00:17:14,492 --> 00:17:19,623 And then a Polish astronomer and priest named Copernicus made a radical proposal: 186 00:17:19,789 --> 00:17:22,042 The Earth was not the center. 187 00:17:22,208 --> 00:17:25,963 It was just one of the planets, and like them, it revolved around the sun. 188 00:17:26,712 --> 00:17:29,556 Many, like the Protestant reformer Martin Luther... 189 00:17:29,715 --> 00:17:32,969 ...took this idea as a scandalous affront to scripture. 190 00:17:33,135 --> 00:17:34,603 They were horrified. 191 00:17:34,762 --> 00:17:39,393 But for one man, Copernicus didn't go far enough. 192 00:17:39,976 --> 00:17:44,322 His name was Giordano Bruno and he was a natural-born rebel. 193 00:17:44,480 --> 00:17:47,905 He longed to bust out of that cramped little universe. 194 00:17:48,067 --> 00:17:50,320 Even as a young Dominican monk in Naples... 195 00:17:50,486 --> 00:17:51,783 ...he was a misfit. 196 00:17:51,946 --> 00:17:54,916 This was a time when there was no freedom of thought in Italy. 197 00:17:55,074 --> 00:17:58,203 But Bruno hungered to know everything about God's creation. 198 00:17:58,369 --> 00:18:01,213 He dared to read the books banned by the church... 199 00:18:01,372 --> 00:18:03,340 ...and that was his undoing. 200 00:18:03,499 --> 00:18:08,380 In one of them, an ancient Roman, a man dead for more than 1500 years... 201 00:18:08,546 --> 00:18:12,022 ...whispered to him of a universe far 202 00:18:12,034 --> 00:18:15,521 greater, one as boundless as his idea of God. 203 00:18:19,599 --> 00:18:20,942 Lucretius asked the reader... 204 00:18:21,100 --> 00:18:23,523 ...to imagine standing at the edge of the universe... 205 00:18:23,686 --> 00:18:25,814 ...and shooting an arrow outward. 206 00:18:25,980 --> 00:18:28,859 If the arrow keeps going, then clearly the universe extends... 207 00:18:29,025 --> 00:18:30,948 ...beyond what you thought was the edge. 208 00:18:31,110 --> 00:18:32,908 But if the arrow doesn't keep going... 209 00:18:33,070 --> 00:18:36,040 ...say it hits a wall, then that wall must lie... 210 00:18:36,198 --> 00:18:38,872 ...beyond what you thought was the edge of the universe. 211 00:18:39,035 --> 00:18:42,380 Now if you stand on that wall and shoot another arrow... 212 00:18:42,538 --> 00:18:44,916 ...there are only the same two possible outcomes: 213 00:18:45,082 --> 00:18:47,505 It either flies forever out into space... 214 00:18:47,668 --> 00:18:49,170 ...or it hits some boundary... 215 00:18:49,337 --> 00:18:52,011 ...where you can stand and shoot yet another arrow. 216 00:18:52,173 --> 00:18:55,473 Either way, the universe is unbounded. 217 00:18:55,635 --> 00:18:57,888 The cosmos must be infinite. 218 00:18:58,512 --> 00:19:00,389 This made perfect sense to Bruno. 219 00:19:00,556 --> 00:19:02,809 The God he worshiped was infinite. 220 00:19:02,975 --> 00:19:06,821 So how, he reasoned, could creation be anything less? 221 00:19:06,979 --> 00:19:08,026 [DOOR OPENS] 222 00:19:21,744 --> 00:19:25,544 It was the last steady job he ever had. 223 00:19:35,132 --> 00:19:40,480 And then, when he was 30, he had the vision that sealed his fate. 224 00:19:40,638 --> 00:19:43,107 In this dream, he awakened to a world... 225 00:19:43,265 --> 00:19:46,235 ...enclosed inside a confining bowl of stars. 226 00:19:47,103 --> 00:19:50,733 This was the cosmos of Bruno's time. 227 00:20:08,165 --> 00:20:10,668 He experienced a sickening moment of fear... 228 00:20:10,835 --> 00:20:14,305 ...as if the bottom of everything was falling away beneath his feet. 229 00:20:14,463 --> 00:20:17,216 But he summoned up his courage. 230 00:20:25,307 --> 00:20:27,981 BRUNO: I spread confident wings to space... 231 00:20:28,144 --> 00:20:31,444 ...and soared toward the infinite, leaving far behind me... 232 00:20:31,605 --> 00:20:34,654 ...what others strained to see from a distance. 233 00:20:34,817 --> 00:20:38,492 Here, there was no up, no down, no edge... 234 00:20:38,654 --> 00:20:39,906 ...no center. 235 00:20:40,072 --> 00:20:43,076 I saw that the sun was just another star... 236 00:20:43,242 --> 00:20:47,497 ...and the stars were other suns, each escorted by other earths... 237 00:20:47,663 --> 00:20:48,789 ...like our own. 238 00:20:48,956 --> 00:20:54,213 The revelation of this immensity was like falling in love. 239 00:20:57,298 --> 00:20:58,925 TYSON". Bruno became an evangelist... 240 00:20:59,091 --> 00:21:02,436 ...spreading the gospel of infinity throughout Europe. 241 00:21:02,595 --> 00:21:06,145 He assumed that other lovers of God would naturally embrace... 242 00:21:06,307 --> 00:21:09,026 ...this grander and more glorious view of creation. 243 00:21:09,810 --> 00:21:12,154 BRUNO: What a fool I was. 244 00:21:13,939 --> 00:21:17,534 TYSON: He was excommunicated by the Roman Catholic Church in his homeland... 245 00:21:17,693 --> 00:21:20,196 ...expelled by the Calvinists in Switzerland... 246 00:21:20,362 --> 00:21:22,456 ...and by the Lutherans in Germany. 247 00:21:23,616 --> 00:21:28,042 Bruno jumped at an invitation to lecture at Oxford in England. 248 00:21:30,331 --> 00:21:32,083 At last, he thought... 249 00:21:32,249 --> 00:21:35,298 ...a chance to share his vision with an audience of his peers. 250 00:21:35,461 --> 00:21:37,463 [ALL CHUCKLING] 251 00:21:39,548 --> 00:21:42,472 I have come to present a new vision of the cosmos. 252 00:21:42,635 --> 00:21:47,232 Copernicus was right to argue that our world is not the center of the universe. 253 00:21:47,389 --> 00:21:49,687 The Earth goes around the sun. 254 00:21:49,850 --> 00:21:51,818 It's a planet, just like the others. 255 00:21:51,977 --> 00:21:56,073 But Copernicus was only the dawn. I bring you the sunrise. 256 00:21:56,232 --> 00:21:59,736 MAN 1: Outrageous. The stars are other fiery suns... 257 00:21:59,902 --> 00:22:04,874 ...made of the same substance as the Earth, and they have their own watery earths... 258 00:22:05,032 --> 00:22:07,911 ...with plants and animals no less noble than our own. 259 00:22:08,077 --> 00:22:10,205 Are you mad or merely ignorant? 260 00:22:10,371 --> 00:22:14,251 Everyone knows there is only one world. What everyone knows is wrong. 261 00:22:14,416 --> 00:22:17,545 Our infinite God has created a boundless universe... 262 00:22:17,711 --> 00:22:19,429 ...with an infinite number of worlds. 263 00:22:19,588 --> 00:22:22,011 Do they not read Aristotle where you come from? 264 00:22:22,174 --> 00:22:23,221 Or even the Bible? 265 00:22:23,384 --> 00:22:27,890 I beg you, reject antiquity, tradition, faith, and authority. 266 00:22:28,055 --> 00:22:31,184 Let us begin anew, by doubting everything we assume has been proven. 267 00:22:31,350 --> 00:22:33,398 MAN 2: Heretic. MAN 3: Infidel! 268 00:22:33,561 --> 00:22:35,279 Your God is too small. 269 00:22:35,437 --> 00:22:37,280 [CROWD SHOUTING INDISTINCTLY] 270 00:22:40,568 --> 00:22:43,196 TYSON". A wiser man would have learned his lesson. 271 00:22:43,946 --> 00:22:46,540 But Bruno was not such a man. 272 00:22:46,699 --> 00:22:50,795 He couldn't keep his soaring vision of the cosmos to himself... 273 00:22:50,953 --> 00:22:55,129 ...despite the fact that the penalty for doing so in his world... 274 00:22:55,291 --> 00:22:59,637 ...was the most vicious form of cruel and unusual punishment. 275 00:23:04,717 --> 00:23:06,264 Giordano Bruno lived at a time... 276 00:23:06,427 --> 00:23:09,772 ...when there was no such thing as the separation of church and state... 277 00:23:09,930 --> 00:23:14,060 ...or the notion that freedom of speech was a sacred right of every individual. 278 00:23:14,226 --> 00:23:17,526 Expressing an idea that didn't conform to traditional belief... 279 00:23:17,688 --> 00:23:20,737 ...could land you in deep trouble. 280 00:23:21,442 --> 00:23:24,742 Recklessly, Bruno returned to Italy. 281 00:23:24,904 --> 00:23:26,030 Maybe he was homesick. 282 00:23:26,196 --> 00:23:29,416 But still, he must have known that his homeland... 283 00:23:29,575 --> 00:23:33,250 ...was one of the most dangerous places in Europe he could possibly go. 284 00:23:33,412 --> 00:23:36,336 The Roman Catholic Church maintained a system of courts... 285 00:23:36,498 --> 00:23:38,296 ...known as the Inquisition... 286 00:23:38,459 --> 00:23:41,838 ...and its sole purpose was to investigate and torment... 287 00:23:42,004 --> 00:23:46,259 ...anyone who dared voice views that differed from theirs. 288 00:23:48,844 --> 00:23:54,977 It wasn't long before Bruno fell into the clutches of the thought police. 289 00:24:00,230 --> 00:24:03,154 This wanderer, who worshiped an infinite universe... 290 00:24:03,317 --> 00:24:06,321 ...languished in confinement for eight years. 291 00:24:06,487 --> 00:24:08,160 Through relentless interrogations... 292 00:24:08,322 --> 00:24:11,121 ...he stubbornly refused to renounce his views. 293 00:24:11,283 --> 00:24:15,834 Why was the church willing to go to such lengths to torment Bruno? 294 00:24:15,996 --> 00:24:18,044 What were they afraid of? 295 00:24:18,624 --> 00:24:24,552 If Bruno was right, then the sacred books and the authority of the church... 296 00:24:24,713 --> 00:24:26,761 ...would be open to question. 297 00:24:26,924 --> 00:24:30,929 Finally, the cardinals of the Inquisition rendered their verdict. 298 00:24:31,095 --> 00:24:34,975 You are found guilty of questioning the Holy Trinity... 299 00:24:35,140 --> 00:24:37,689 ...and the divinity of Jesus Christ. 300 00:24:37,851 --> 00:24:41,230 Of believing that God's wrath is not eternal... 301 00:24:41,397 --> 00:24:43,445 ...that everyone will be saved. 302 00:24:43,607 --> 00:24:47,328 Of asserting the existence of other worlds. 303 00:24:48,070 --> 00:24:49,162 MAN: Throw him in his cell. 304 00:24:49,321 --> 00:24:51,415 All of the books you have written... 305 00:24:51,573 --> 00:24:54,873 ...will be gathered up and burned in St. Peter's Square. 306 00:24:55,035 --> 00:24:58,460 Reverend Father, these eight years of confinement... 307 00:24:58,622 --> 00:25:02,422 ...have given me much time to reflect. So you will recant? 308 00:25:02,584 --> 00:25:04,552 My love and reverence for the creator... 309 00:25:04,712 --> 00:25:08,091 ...inspires in me the vision of an infinite creation. 310 00:25:08,257 --> 00:25:12,307 You shall be turned over to the governor of Rome... 311 00:25:12,469 --> 00:25:15,097 ...to administer the appropriate punishment... 312 00:25:15,264 --> 00:25:17,642 ...for those who will not repent. 313 00:25:17,808 --> 00:25:19,276 MAN: Back to prison. 314 00:25:20,644 --> 00:25:25,070 It may be that you are more afraid to deliver this judgment... 315 00:25:25,232 --> 00:25:26,609 ...than I am to hear it. 316 00:25:55,971 --> 00:25:58,440 [CROWD SHOUTING INDISTINCTLY] 317 00:26:26,794 --> 00:26:28,671 [SHOUTING CONTINUES] 318 00:26:34,843 --> 00:26:37,096 Ten years after Bruno's martyrdom... 319 00:26:37,262 --> 00:26:39,481 ...Galileo first looked through a telescope... 320 00:26:39,640 --> 00:26:42,268 ...realizing that Bruno had been right all along. 321 00:26:42,434 --> 00:26:46,689 The Milky Way was made of countless stars invisible to the naked eye... 322 00:26:46,855 --> 00:26:51,031 ...and some of those lights in the sky were actually other worlds. 323 00:26:51,193 --> 00:26:53,036 Bruno was no scientist. 324 00:26:53,195 --> 00:26:55,539 His vision of the cosmos was a lucky guess... 325 00:26:55,697 --> 00:26:58,166 ...because he had no evidence to support it. 326 00:26:58,325 --> 00:27:01,875 Like most guesses, it could well have turned out wrong. 327 00:27:02,037 --> 00:27:05,792 But once the idea was in the air, it gave others a target to aim at. 328 00:27:05,958 --> 00:27:07,460 If only to disprove it. 329 00:27:10,254 --> 00:27:13,098 Bruno glimpsed the vastness of space... 330 00:27:13,257 --> 00:27:18,855 ...but he had no inkling of the staggering immensity of time. 331 00:27:21,515 --> 00:27:24,860 How can we humans, who rarely live more than a century... 332 00:27:25,018 --> 00:27:27,396 ...hope to grasp the vast expanse of time... 333 00:27:27,563 --> 00:27:30,157 ...that is the history of the cosmos? 334 00:27:30,315 --> 00:27:34,616 The universe is 13.8 thousand million years old. 335 00:27:34,778 --> 00:27:37,327 In order to imagine all of cosmic time... 336 00:27:37,489 --> 00:27:41,289 ...let's compress it into a single calendar year. 337 00:27:53,755 --> 00:27:58,727 The cosmic calendar begins on January 1st with the birth of our universe. 338 00:27:58,886 --> 00:28:02,641 It contains everything that's happened since then up to now... 339 00:28:02,806 --> 00:28:07,061 ...which on this calendar is midnight, December 31 st. 340 00:28:07,227 --> 00:28:11,152 On this scale, every month represents about a billion years. 341 00:28:11,315 --> 00:28:15,741 Every day represents nearly 40 million years. 342 00:28:15,903 --> 00:28:17,701 Let's go back as far as we can... 343 00:28:17,863 --> 00:28:21,458 ...to the very first moment of the universe. 344 00:28:21,617 --> 00:28:25,963 January 1st. The Big Bang. 345 00:28:36,506 --> 00:28:39,976 It's as far back as we can see in time. 346 00:28:40,135 --> 00:28:42,137 For now. 347 00:28:42,971 --> 00:28:47,852 Our entire universe emerged from a point smaller than a single atom. 348 00:28:48,018 --> 00:28:50,862 Space itself exploded in a cosmic fire... 349 00:28:51,021 --> 00:28:53,319 ...launching the expansion of the universe... 350 00:28:53,482 --> 00:28:57,578 ...and giving birth to all the energy and all the matter we know today. 351 00:28:58,403 --> 00:29:01,657 I know that sounds crazy, but there's strong observational evidence... 352 00:29:01,823 --> 00:29:03,496 ...to support the Big Bang theory. 353 00:29:03,659 --> 00:29:06,162 And it includes the amount of helium in the cosmos... 354 00:29:06,328 --> 00:29:09,673 ...and the glow of radio waves left over from the explosion. 355 00:29:09,831 --> 00:29:12,459 As it expanded, the universe cooled... 356 00:29:12,626 --> 00:29:16,676 ...and there was darkness for about 200 million years. 357 00:29:17,381 --> 00:29:20,635 Gravity was pulling together clumps of gas and heating them... 358 00:29:20,801 --> 00:29:25,307 ...until the first stars burst into light on January 10th. 359 00:29:30,894 --> 00:29:37,402 On January 13th, these stars coalesced into the first small galaxies. 360 00:29:39,194 --> 00:29:42,038 These galaxies merged to form still larger ones... 361 00:29:42,197 --> 00:29:45,167 ...including our own Milky Way... 362 00:29:45,867 --> 00:29:49,622 ...which formed about 11 billion years ago... 363 00:29:49,788 --> 00:29:53,042 ...on March 15 of the cosmic year. 364 00:29:54,501 --> 00:29:57,175 Hundreds of billions of suns. 365 00:29:57,337 --> 00:29:59,055 Which one is ours? 366 00:29:59,214 --> 00:30:04,846 It's not yet born. It will rise from the ashes of other stars. 367 00:30:05,637 --> 00:30:08,766 See those lights flashing like paparazzi? 368 00:30:08,932 --> 00:30:11,230 Each one is a supernova... 369 00:30:11,393 --> 00:30:14,112 ...the blazing death of a giant star. 370 00:30:14,980 --> 00:30:17,733 Stars die and are born in places like this one... 371 00:30:17,899 --> 00:30:19,446 ...a stellar nursery. 372 00:30:19,609 --> 00:30:24,035 They condense like raindrops from giant clouds of gas and dust. 373 00:30:24,197 --> 00:30:28,703 They get so hot that the nuclei of the atoms fuse together deep within them... 374 00:30:28,869 --> 00:30:32,965 ...to make the oxygen we breathe, the carbon in our muscles... 375 00:30:33,123 --> 00:30:36,218 ...the calcium in our bones, the iron in our blood. 376 00:30:36,376 --> 00:30:41,883 All of it was cooked in the fiery hearts of long-vanished stars. 377 00:30:42,049 --> 00:30:45,519 You, me, everyone. 378 00:30:45,677 --> 00:30:49,682 We are made of star stuff. 379 00:30:51,266 --> 00:30:53,985 This star stuff is recycled and enriched... 380 00:30:54,144 --> 00:30:58,650 ...again and again, through succeeding generations of stars. 381 00:31:02,235 --> 00:31:04,784 How much longer until the birth of our sun? 382 00:31:04,946 --> 00:31:06,448 A long time. 383 00:31:06,615 --> 00:31:10,620 It won't begin to shine for another six billion years. 384 00:31:12,120 --> 00:31:17,297 Our sun's birthday is August 31 st on the cosmic calendar... 385 00:31:19,044 --> 00:31:21,797 ...four and a half billion years ago. 386 00:31:22,381 --> 00:31:24,679 As with the other worlds of our solar system... 387 00:31:24,841 --> 00:31:27,765 ...Earth was formed from a disk of gas and dust... 388 00:31:27,928 --> 00:31:29,771 ...orbiting the newborn sun. 389 00:31:29,930 --> 00:31:34,276 Repeated collisions produced a growing ball of debris. 390 00:31:39,648 --> 00:31:42,322 See that asteroid? No, not that one. 391 00:31:42,484 --> 00:31:44,236 The one over there. 392 00:31:44,403 --> 00:31:48,124 We exist because the gravity of that one next to it... 393 00:31:48,281 --> 00:31:51,251 ...just nudged it an inch to the left. 394 00:31:51,410 --> 00:31:55,540 What difference could an inch make on the scale of the solar system? 395 00:31:55,705 --> 00:31:58,925 Just wait, you'll see. 396 00:31:59,835 --> 00:32:04,181 The Earth took one hell of a beating in its first billion years. 397 00:32:06,591 --> 00:32:09,970 Fragments of orbiting debris collided and coalesced... 398 00:32:10,137 --> 00:32:13,516 ...until they snowballed to form our moon. 399 00:32:14,516 --> 00:32:18,111 The moon is a souvenir of that violent epoch. 400 00:32:18,270 --> 00:32:20,944 If you stood on the surface of that long ago Earth... 401 00:32:21,106 --> 00:32:23,859 ...the moon would have looked a hundred times brighter. 402 00:32:24,025 --> 00:32:26,073 It was ten times closer back then... 403 00:32:26,236 --> 00:32:30,366 ...locked in a much more intimate gravitational embrace. 404 00:32:30,532 --> 00:32:33,706 As the Earth cooled, seas began to form. 405 00:32:33,869 --> 00:32:36,418 The tides were a thousand times higher then. 406 00:32:36,580 --> 00:32:42,053 Over the eons, tidal friction within the Earth pushed the moon away. 407 00:32:48,216 --> 00:32:52,722 Life began somewhere around here, September 21 st... 408 00:32:52,888 --> 00:32:56,358 ...three and a half billion years ago on our little world. 409 00:32:56,516 --> 00:32:58,518 We still don't know how life got started. 410 00:32:58,685 --> 00:33:02,360 For all we know, it may have come from another part of the Milky Way. 411 00:33:02,522 --> 00:33:06,402 The origin of life is one of the greatest unsolved mysteries of science. 412 00:33:09,946 --> 00:33:14,793 That's life cooking, evolving all the biochemical recipes... 413 00:33:14,951 --> 00:33:18,251 ...for its incredibly complex activities. 414 00:33:18,413 --> 00:33:22,259 By November 9th, life was breathing... 415 00:33:22,417 --> 00:33:28,015 ...moving, eating, responding to its environment. 416 00:33:28,173 --> 00:33:31,177 We owe a lot to those pioneering microbes. 417 00:33:31,343 --> 00:33:33,220 Oh, yeah, one other thing. 418 00:33:33,386 --> 00:33:36,606 They also invented sex. 419 00:33:39,768 --> 00:33:42,362 December 17th was quite a day. 420 00:33:42,521 --> 00:33:44,273 Life in the sea really took off. 421 00:33:44,940 --> 00:33:48,444 It was exploding with a diversity of larger plants and animals. 422 00:33:50,111 --> 00:33:53,615 Tiktaalik was one of the first animals to venture onto land. 423 00:33:56,368 --> 00:33:58,791 It must have felt like visiting another planet. 424 00:34:00,705 --> 00:34:05,131 Forests, dinosaurs, birds, insects... 425 00:34:05,585 --> 00:34:08,464 ...all evolved in the final week of December. 426 00:34:09,381 --> 00:34:10,428 The first flower... 427 00:34:11,675 --> 00:34:14,645 ...bloomed on December 28th. 428 00:34:18,598 --> 00:34:23,024 As these ancient forests grew and died and sank beneath the surface... 429 00:34:23,186 --> 00:34:26,156 ...their remains transformed into coal. 430 00:34:26,314 --> 00:34:28,442 Three hundred million years later... 431 00:34:28,608 --> 00:34:32,408 ...we humans are burning most of that coal to power... 432 00:34:32,571 --> 00:34:34,790 ...and imperil our civilization. 433 00:34:39,828 --> 00:34:43,002 Remember that asteroid back in the formation of the solar system? 434 00:34:43,164 --> 00:34:45,258 The one that got nudged a little to the left? 435 00:34:45,417 --> 00:34:47,340 Well, here it comes. 436 00:34:48,336 --> 00:34:53,684 It's 6:24 a.m. on December 30th on the Cosmic Calendar. 437 00:34:54,384 --> 00:34:55,852 [EXPLOSION] 438 00:35:01,850 --> 00:35:05,571 For more than a hundred million years, the dinosaurs were lords of the Earth... 439 00:35:05,729 --> 00:35:10,200 ...while our ancestors, small mammals, scurried fearfully underfoot. 440 00:35:11,026 --> 00:35:12,778 The asteroid changed all that. 441 00:35:12,944 --> 00:35:16,665 Suppose it hadn't been nudged at all. It would have missed the Earth entirely... 442 00:35:16,823 --> 00:35:20,293 ...and for all we know, the dinosaurs might still be here, but we wouldn't. 443 00:35:20,452 --> 00:35:23,376 This is a good example of the extreme contingency... 444 00:35:23,538 --> 00:35:26,007 ...the chance nature of existence. 445 00:35:28,835 --> 00:35:32,385 The universe is already more than 13 and half billion years old. 446 00:35:32,547 --> 00:35:35,050 Still no sign of us. 447 00:35:35,216 --> 00:35:38,390 In the vast ocean of time that this calendar represents... 448 00:35:38,553 --> 00:35:41,397 ...we humans only evolved within the last hour... 449 00:35:41,556 --> 00:35:46,062 ...of the last day of the cosmic year. 450 00:35:52,400 --> 00:35:55,574 11:59 and 46 seconds. 451 00:35:55,737 --> 00:36:00,368 All of recorded history occupies only the last 14 seconds... 452 00:36:00,533 --> 00:36:05,960 ...and every person you've ever heard of lived somewhere in there. 453 00:36:06,581 --> 00:36:10,711 All those kings and battles, migrations and inventions... 454 00:36:10,877 --> 00:36:14,427 ...wars and loves, everything in the history books... 455 00:36:14,589 --> 00:36:19,720 ...happened here, in the last seconds of the cosmic calendar. 456 00:36:19,886 --> 00:36:23,891 But if we want to explore such a brief moment of cosmic time... 457 00:36:26,768 --> 00:36:29,271 ...we'll have to change scale. 458 00:36:48,206 --> 00:36:50,675 We are newcomers to the cosmos. 459 00:36:50,834 --> 00:36:55,806 Our own story only begins on the last night of the cosmic year. 460 00:36:55,964 --> 00:36:58,808 It's 9:45 on New Year's Eve. 461 00:36:58,967 --> 00:37:01,140 Three and a half million years ago... 462 00:37:01,302 --> 00:37:05,102 ...our ancestors, yours and mine, left these traces. 463 00:37:07,016 --> 00:37:09,940 We stood up and parted ways from them. 464 00:37:10,103 --> 00:37:11,855 Once we were standing on two feet... 465 00:37:12,021 --> 00:37:15,241 ...our eyes were no longer fixated on the ground. 466 00:37:15,400 --> 00:37:19,280 Now we were free to look up and wonder. 467 00:37:21,489 --> 00:37:27,872 For the longest part of human existence, say the last 40,000 generations... 468 00:37:28,037 --> 00:37:32,759 ...we were Wanderers, living in small bands of hunters and gatherers... 469 00:37:32,917 --> 00:37:37,388 ...making tools, controlling fire, naming things... 470 00:37:37,547 --> 00:37:42,599 ...all within the last hour of the cosmic calendar. 471 00:37:49,684 --> 00:37:53,154 To find out what happens next, we'll have to change scale... 472 00:37:53,313 --> 00:37:59,411 ...to see the last minute of the last night of the cosmic year. 473 00:37:59,569 --> 00:38:04,200 11:59. We're so very young on the time scale of the universe... 474 00:38:04,365 --> 00:38:06,959 ...that we didn't start painting our first pictures... 475 00:38:07,118 --> 00:38:10,998 ...until the last 60 seconds of the cosmic year... 476 00:38:11,164 --> 00:38:14,839 ...a mere 30,000 years ago. 477 00:38:17,170 --> 00:38:19,047 [ANIMALS GRUNTING] 478 00:38:22,133 --> 00:38:24,556 This is when we invented astronomy. 479 00:38:24,719 --> 00:38:27,939 In fact, we're all descended from astronomers. 480 00:38:28,097 --> 00:38:31,271 Our survival depended on knowing how to read the stars... 481 00:38:31,434 --> 00:38:33,732 ...in order to predict the coming of the winter... 482 00:38:33,895 --> 00:38:36,364 ...and the migration of the wild herds. 483 00:38:36,523 --> 00:38:39,493 And then, around 10,000 years ago... 484 00:38:39,651 --> 00:38:42,575 ...there began a revolution in the way we lived. 485 00:38:42,737 --> 00:38:45,786 Our ancestors learned how to shape their environment... 486 00:38:45,949 --> 00:38:48,122 ...taming wild plants and animals... 487 00:38:48,284 --> 00:38:51,083 ...cultivating land and settling down. 488 00:38:51,246 --> 00:38:53,965 This changed everything. 489 00:38:54,123 --> 00:38:59,095 For the first time in our history, we had more stuff than we could carry. 490 00:38:59,254 --> 00:39:01,677 We needed a way to keep track of it. 491 00:39:01,840 --> 00:39:03,592 At 14 seconds to midnight... 492 00:39:03,758 --> 00:39:07,433 ...or about 6000 years ago, we invented writing. 493 00:39:07,595 --> 00:39:11,395 And it wasn't long before we started recording more than bushels of grain. 494 00:39:11,558 --> 00:39:13,856 Writing allowed us to save our thoughts... 495 00:39:14,018 --> 00:39:17,113 ...and send them much further in space and time. 496 00:39:17,272 --> 00:39:19,115 Tiny markings on a clay tablet... 497 00:39:19,274 --> 00:39:22,528 ...became a means for us to vanquish mortality. 498 00:39:22,694 --> 00:39:25,288 It shook the world. 499 00:39:25,446 --> 00:39:28,541 Moses was born seven seconds ago. 500 00:39:28,700 --> 00:39:31,203 Buddha, six seconds ago. 501 00:39:31,369 --> 00:39:34,623 Jesus, five seconds ago. 502 00:39:34,789 --> 00:39:38,134 Mohammed, three seconds ago. 503 00:39:38,293 --> 00:39:41,968 It was not even two seconds ago that, for better or worse... 504 00:39:42,130 --> 00:39:44,804 ...the two halves of the Earth discovered each other. 505 00:39:44,966 --> 00:39:46,968 And it was only in the very last second... 506 00:39:47,135 --> 00:39:50,139 ...of the cosmic calendar that we began to use science... 507 00:39:50,305 --> 00:39:53,434 ...to reveal nature's secrets and her laws. 508 00:39:53,600 --> 00:39:57,730 The scientific method is so powerful that in a mere four centuries... 509 00:39:57,896 --> 00:40:00,183 ...it has taken us from Galileo's first look 510 00:40:00,195 --> 00:40:02,493 through a telescope at another world... 511 00:40:02,650 --> 00:40:05,449 ...to leaving our footprints on the moon. 512 00:40:05,612 --> 00:40:09,617 It allowed us to look out across space and time... 513 00:40:09,782 --> 00:40:14,288 ...to discover where and when we are in the cosmos. 514 00:40:15,163 --> 00:40:19,293 SAGAN: We are a way for the cosmos to know itself. 515 00:40:19,459 --> 00:40:21,962 Carl Sagan guided the maiden voyage of Cosmos... 516 00:40:22,128 --> 00:40:23,675 ...a generation ago. 517 00:40:23,838 --> 00:40:27,183 He was the most successful science communicator of the 20th century... 518 00:40:27,342 --> 00:40:29,845 ...but he was first and foremost a scientist. 519 00:40:31,596 --> 00:40:35,601 Carl contributed enormously to our knowledge of the planets. 520 00:40:35,767 --> 00:40:38,737 He correctly predicted the existence of methane lakes... 521 00:40:38,895 --> 00:40:41,318 ...on Saturn's giant moon Titan. 522 00:40:41,481 --> 00:40:43,950 He showed that the atmosphere of the early Earth... 523 00:40:44,108 --> 00:40:46,861 ...must have contained powerful greenhouse gases. 524 00:40:47,654 --> 00:40:51,079 He was the first to understand that seasonal changes on Mars... 525 00:40:51,240 --> 00:40:53,368 ...were due to windblown dust. 526 00:40:53,534 --> 00:40:57,289 Carl was a pioneer in the search for extraterrestrial life... 527 00:40:57,455 --> 00:40:59,298 ...and intelligence. 528 00:40:59,457 --> 00:41:02,631 He played a leading role in every major spacecraft mission... 529 00:41:02,794 --> 00:41:07,550 ...to explore the solar system during the first 40 years of the Space Age. 530 00:41:09,467 --> 00:41:11,561 But that's not all he did. 531 00:41:14,514 --> 00:41:18,485 This is Carl Sagan's own calendar from 1975. 532 00:41:22,021 --> 00:41:23,489 Who was I back then? 533 00:41:24,357 --> 00:41:26,826 I was just a 17-year-old kid from the Bronx... 534 00:41:26,985 --> 00:41:28,908 ...with dreams of becoming a scientist... 535 00:41:29,070 --> 00:41:32,119 ...and somehow the world's most famous astronomer found time... 536 00:41:32,281 --> 00:41:35,000 ...to invite me to Ithaca, in upstate New York... 537 00:41:35,159 --> 00:41:36,706 ...and spend a Saturday with him. 538 00:41:38,037 --> 00:41:40,586 I remember that snowy day like it was yesterday. 539 00:41:40,748 --> 00:41:42,045 He met me at the bus stop... 540 00:41:42,208 --> 00:41:45,428 ...and showed me his laboratory at Cornell University. 541 00:41:45,586 --> 00:41:50,217 Carl reached behind his desk and inscribed this book for me. 542 00:41:53,177 --> 00:41:57,353 "For Neil, a future astronomer. Carl." 543 00:41:58,182 --> 00:42:01,231 At the end of the day, he drove me back to the bus station. 544 00:42:01,394 --> 00:42:02,896 The snow was falling harder. 545 00:42:03,062 --> 00:42:06,407 He wrote his phone number, his home phone number, on a scrap of paper... 546 00:42:06,566 --> 00:42:08,819 ...and he said, "if the bus can't get through... 547 00:42:08,985 --> 00:42:13,035 ...call me and spend the night at my home with my family." 548 00:42:13,197 --> 00:42:15,450 I already knew I wanted to become a scientist... 549 00:42:15,616 --> 00:42:17,744 ...but that afternoon I learned from Carl... 550 00:42:17,910 --> 00:42:19,787 ...the kind of person I wanted to become. 551 00:42:20,621 --> 00:42:23,340 He reached out to me and to countless others... 552 00:42:23,499 --> 00:42:28,380 ...inspiring so many of us to study, teach and do science. 553 00:42:28,546 --> 00:42:32,801 Science is a cooperative enterprise, spanning the generations. 554 00:42:32,967 --> 00:42:37,723 It's the passing of a torch from teacher to student to teacher. 555 00:42:37,889 --> 00:42:41,268 A community of minds reaching back to antiquity... 556 00:42:41,434 --> 00:42:43,027 ...and forward to the stars. 557 00:42:43,186 --> 00:42:45,609 Now, come with me. 558 00:42:45,772 --> 00:42:49,322 Our journey is just beginning.