[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:00.08,0:00:02.65,Default,,0000,0000,0000,,Equipped with his five senses
Dialogue: 0,0:00:02.72,0:00:05.59,Default,,0000,0000,0000,,man explores the universe around him
Dialogue: 0,0:00:05.66,0:00:07.99,Default,,0000,0000,0000,,and calls the adventure Science.
Dialogue: 0,0:01:09.38,0:01:12.40,Default,,0000,0000,0000,,Things around us\Naren't always what they seem.
Dialogue: 0,0:01:29.17,0:01:33.40,Default,,0000,0000,0000,,ln the everyday world,\Nwe use a simple scale, ourselves
Dialogue: 0,0:01:33.51,0:01:36.27,Default,,0000,0000,0000,,to know what's small and what's large.
Dialogue: 0,0:01:47.06,0:01:49.55,Default,,0000,0000,0000,,But what about the worlds that lie beyond?
Dialogue: 0,0:01:52.06,0:01:55.62,Default,,0000,0000,0000,,What is truly large and truly small?
Dialogue: 0,0:02:04.04,0:02:07.38,Default,,0000,0000,0000,,To explore, to observe
Dialogue: 0,0:02:07.78,0:02:11.22,Default,,0000,0000,0000,,to understand the wider world\Nwe call the universe:
Dialogue: 0,0:02:12.32,0:02:15.12,Default,,0000,0000,0000,,This is one of the great human adventures.
Dialogue: 0,0:02:30.28,0:02:35.08,Default,,0000,0000,0000,,As we look out at the distant horizon,\Nwe may ask ourselves
Dialogue: 0,0:02:35.69,0:02:38.95,Default,,0000,0000,0000,,what is our true place in the universe?
Dialogue: 0,0:02:42.53,0:02:44.89,Default,,0000,0000,0000,,We are all travelers
Dialogue: 0,0:02:44.96,0:02:47.99,Default,,0000,0000,0000,,on an unending voyage of discovery.
Dialogue: 0,0:03:27.99,0:03:32.01,Default,,0000,0000,0000,,More than 25 centuries ago,\Namong the Greek lslands
Dialogue: 0,0:03:32.09,0:03:36.15,Default,,0000,0000,0000,,here at the vibrant crossroads of Africa,\NAsia and Europe
Dialogue: 0,0:03:36.56,0:03:41.06,Default,,0000,0000,0000,,philosophers devised rational theories\Nabout the world around them.
Dialogue: 0,0:03:44.88,0:03:47.84,Default,,0000,0000,0000,,The wondrous waves and foams\Nof nature, they said
Dialogue: 0,0:03:48.18,0:03:49.77,Default,,0000,0000,0000,,could be understood.
Dialogue: 0,0:04:20.35,0:04:25.05,Default,,0000,0000,0000,,One Greek thinker suggested\Nthat the Earth moved around the sun.
Dialogue: 0,0:04:28.60,0:04:32.83,Default,,0000,0000,0000,,Another taught that everything,\Nthe work of man and nature
Dialogue: 0,0:04:33.14,0:04:36.66,Default,,0000,0000,0000,,was made of particles too small to see.
Dialogue: 0,0:04:41.41,0:04:44.38,Default,,0000,0000,0000,,Others estimated the sizes\Nof the Earth and the moon
Dialogue: 0,0:04:44.45,0:04:47.55,Default,,0000,0000,0000,,and the distances between them,\Nand reasoned
Dialogue: 0,0:04:47.62,0:04:49.28,Default,,0000,0000,0000,,both were spheres.
Dialogue: 0,0:04:52.43,0:04:56.59,Default,,0000,0000,0000,,But it would be centuries before we had\Nthe tools to extend our vision
Dialogue: 0,0:04:56.80,0:04:59.83,Default,,0000,0000,0000,,and confirm the wisdom\Nof these early thinkers.
Dialogue: 0,0:05:01.77,0:05:03.44,Default,,0000,0000,0000,,ln the meantime
Dialogue: 0,0:05:03.51,0:05:07.64,Default,,0000,0000,0000,,people around the world\Ngazed on the stars and gave them names.
Dialogue: 0,0:05:08.68,0:05:13.38,Default,,0000,0000,0000,,Most assumed the Earth was the center\Nof an unchanging universe.
Dialogue: 0,0:05:47.87,0:05:49.70,Default,,0000,0000,0000,,Two thousand years passed
Dialogue: 0,0:05:49.77,0:05:53.57,Default,,0000,0000,0000,,before a revolutionary breakthrough\Nwas made by a mathematics professor
Dialogue: 0,0:05:53.64,0:05:56.94,Default,,0000,0000,0000,,in the ancient,\Nmaritime republic of Venice.
Dialogue: 0,0:05:58.11,0:06:01.57,Default,,0000,0000,0000,,ln 1609, Galileo Galilei
Dialogue: 0,0:06:01.82,0:06:05.81,Default,,0000,0000,0000,,demonstrated an instrument\Nthat would soon be called a telescope.
Dialogue: 0,0:06:09.100,0:06:11.86,Default,,0000,0000,0000,,From the tallest bell towers
Dialogue: 0,0:06:11.93,0:06:14.56,Default,,0000,0000,0000,,he showed the device\Ncould spot approaching ships
Dialogue: 0,0:06:14.63,0:06:17.87,Default,,0000,0000,0000,,hours before their sails were visible\Nto the naked eye.
Dialogue: 0,0:06:19.71,0:06:22.97,Default,,0000,0000,0000,,Later, when he aimed his telescope\Nat the night sky
Dialogue: 0,0:06:23.24,0:06:26.68,Default,,0000,0000,0000,,Galileo discovered that the moon\Nwas a world of mountains.
Dialogue: 0,0:06:27.35,0:06:29.32,Default,,0000,0000,0000,,Jupiter had its own moons
Dialogue: 0,0:06:29.45,0:06:32.65,Default,,0000,0000,0000,,and the Milky Way\Nwas a band of countless stars.
Dialogue: 0,0:06:38.06,0:06:40.93,Default,,0000,0000,0000,,Our own cosmic voyage begins here
Dialogue: 0,0:06:41.14,0:06:44.87,Default,,0000,0000,0000,,in the center of Galileo's Venice,\NSt. Mark's Square.
Dialogue: 0,0:06:50.78,0:06:54.48,Default,,0000,0000,0000,,Since the universe is a big place,\Nwe could easily get lost
Dialogue: 0,0:06:55.09,0:06:58.58,Default,,0000,0000,0000,,so we'll need signposts\Nto give us a sense of scale.
Dialogue: 0,0:07:01.63,0:07:04.65,Default,,0000,0000,0000,,The acrobats' ring is one meter wide.
Dialogue: 0,0:07:08.00,0:07:11.94,Default,,0000,0000,0000,,The crowd is ten times wider,\Nten meters across.
Dialogue: 0,0:07:12.01,0:07:14.24,Default,,0000,0000,0000,,Larger by one power of ten.
Dialogue: 0,0:07:18.58,0:07:21.82,Default,,0000,0000,0000,,Now, with every step, every ring
Dialogue: 0,0:07:22.29,0:07:25.26,Default,,0000,0000,0000,,we travel ten times farther from Venice
Dialogue: 0,0:07:25.49,0:07:28.69,Default,,0000,0000,0000,,and our view of the universe\Nis ten times wider.
Dialogue: 0,0:07:32.10,0:07:34.93,Default,,0000,0000,0000,,The 100-meter ring surrounds St. Mark's
Dialogue: 0,0:07:35.34,0:07:39.28,Default,,0000,0000,0000,,and 1,000 meters, one kilometer,\Nthe city's center.
Dialogue: 0,0:07:41.51,0:07:45.97,Default,,0000,0000,0000,,As our speed increases,\Nfour steps, four powers of ten
Dialogue: 0,0:07:46.15,0:07:51.18,Default,,0000,0000,0000,,reveal all the islands of Venice,\Nthe Adriatic Sea and Northern ltaly.
Dialogue: 0,0:07:58.57,0:08:03.30,Default,,0000,0000,0000,,Six steps take in Europe\Nfrom Germany across to the Balkans.
Dialogue: 0,0:08:07.55,0:08:10.41,Default,,0000,0000,0000,,And soon, we can see the entire planet.
Dialogue: 0,0:08:11.05,0:08:12.85,Default,,0000,0000,0000,,Our home in space.
Dialogue: 0,0:08:24.63,0:08:26.83,Default,,0000,0000,0000,,Eight steps on our outward journey
Dialogue: 0,0:08:26.94,0:08:31.20,Default,,0000,0000,0000,,eight powers of ten, and we pass\Nthe farthest reaches of human travel:
Dialogue: 0,0:08:32.51,0:08:33.67,Default,,0000,0000,0000,,The moon.
Dialogue: 0,0:08:59.51,0:09:02.95,Default,,0000,0000,0000,,lf we visualize the paths\Nthat the nine planets take
Dialogue: 0,0:09:03.02,0:09:05.14,Default,,0000,0000,0000,,in their orbits around the sun
Dialogue: 0,0:09:06.46,0:09:09.29,Default,,0000,0000,0000,,at 13 steps from St. Mark's Square
Dialogue: 0,0:09:09.83,0:09:13.26,Default,,0000,0000,0000,,the entire solar system comes into view.
Dialogue: 0,0:09:22.58,0:09:26.54,Default,,0000,0000,0000,,And with 15 steps, 15 powers of ten
Dialogue: 0,0:09:27.25,0:09:30.88,Default,,0000,0000,0000,,we can see our sun is just another star.
Dialogue: 0,0:09:31.39,0:09:35.16,Default,,0000,0000,0000,,From here on,\Nour voyage will be measured in light-years.
Dialogue: 0,0:09:35.76,0:09:38.99,Default,,0000,0000,0000,,The distance light travels in an entire year.
Dialogue: 0,0:09:41.30,0:09:45.10,Default,,0000,0000,0000,,Only now do we fly past\Nour nearest neighbor stars
Dialogue: 0,0:09:45.71,0:09:48.30,Default,,0000,0000,0000,,almost five light-years away.
Dialogue: 0,0:09:49.91,0:09:53.18,Default,,0000,0000,0000,,The same journey at the speed\Nof today's spacecraft
Dialogue: 0,0:09:53.38,0:09:56.58,Default,,0000,0000,0000,,would last 100,000 years.
Dialogue: 0,0:10:03.73,0:10:06.22,Default,,0000,0000,0000,,As we cross the perpetual night
Dialogue: 0,0:10:06.30,0:10:09.70,Default,,0000,0000,0000,,our voyage takes us up and out\Nof our sun's neighborhood
Dialogue: 0,0:10:09.84,0:10:13.04,Default,,0000,0000,0000,,near the edge\Nof a great pinwheel of stars.
Dialogue: 0,0:10:35.64,0:10:38.37,Default,,0000,0000,0000,,The Milky Way is actually a spiral galaxy
Dialogue: 0,0:10:38.81,0:10:43.27,Default,,0000,0000,0000,,and our own sun is just one\Nof a hundred billion stars in it.
Dialogue: 0,0:10:44.52,0:10:48.25,Default,,0000,0000,0000,,At this immense scale, 23 powers of ten
Dialogue: 0,0:10:48.59,0:10:51.28,Default,,0000,0000,0000,,each shining light we see is not a star
Dialogue: 0,0:10:51.86,0:10:55.85,Default,,0000,0000,0000,,but an entire galaxy\Ncomposed of countless stars.
Dialogue: 0,0:10:57.63,0:11:01.69,Default,,0000,0000,0000,,Astronomers have discovered\Ngalaxies are flying away from one another.
Dialogue: 0,0:11:02.50,0:11:05.44,Default,,0000,0000,0000,,The universe is expanding.
Dialogue: 0,0:11:07.31,0:11:09.94,Default,,0000,0000,0000,,Our own galaxy, and all the others
Dialogue: 0,0:11:10.11,0:11:13.57,Default,,0000,0000,0000,,form clusters and superclusters\Nof stupendous size
Dialogue: 0,0:11:13.79,0:11:16.55,Default,,0000,0000,0000,,hundreds of millions\Nof light-years across.
Dialogue: 0,0:11:20.23,0:11:24.22,Default,,0000,0000,0000,,And here, about 15 billion light-years\Nfrom Venice
Dialogue: 0,0:11:24.93,0:11:28.23,Default,,0000,0000,0000,,we approach the outer limits\Nof the visible universe.
Dialogue: 0,0:11:29.11,0:11:33.77,Default,,0000,0000,0000,,What lies beyond this cosmic horizon,\Nwe cannot see
Dialogue: 0,0:11:35.11,0:11:37.05,Default,,0000,0000,0000,,and do not know.
Dialogue: 0,0:11:52.94,0:11:56.93,Default,,0000,0000,0000,,While Galileo's telescope\Nallowed us to take an outward voyage
Dialogue: 0,0:11:57.01,0:12:00.24,Default,,0000,0000,0000,,another innovation,\Nhere in the Dutch town of Delft
Dialogue: 0,0:12:00.65,0:12:03.64,Default,,0000,0000,0000,,would lead us on an inward journey\Nof discovery.
Dialogue: 0,0:12:14.53,0:12:16.33,Default,,0000,0000,0000,,Over three centuries ago
Dialogue: 0,0:12:16.43,0:12:19.100,Default,,0000,0000,0000,,Anton van Leeuwenhoek\Nperfected the early microscope
Dialogue: 0,0:12:20.27,0:12:23.57,Default,,0000,0000,0000,,and used it to study droplets\Nfrom the waterways of Holland.
Dialogue: 0,0:12:42.33,0:12:44.27,Default,,0000,0000,0000,,Come on, over here.
Dialogue: 0,0:12:47.81,0:12:50.21,Default,,0000,0000,0000,,As students today\Nmake their own discoveries
Dialogue: 0,0:12:50.28,0:12:52.64,Default,,0000,0000,0000,,imagine the moment\Nwhen van Leeuwenhoek
Dialogue: 0,0:12:52.71,0:12:55.15,Default,,0000,0000,0000,,peered through\Nhis more powerful instrument
Dialogue: 0,0:12:55.22,0:12:59.59,Default,,0000,0000,0000,,and discovered a living kingdom\Nin a drop of water.
Dialogue: 0,0:13:07.80,0:13:10.70,Default,,0000,0000,0000,,This busy world of single-cell paramecia
Dialogue: 0,0:13:11.04,0:13:13.23,Default,,0000,0000,0000,,is only one millimeter across.
Dialogue: 0,0:13:13.87,0:13:17.24,Default,,0000,0000,0000,,Three powers of ten smaller than a meter.
Dialogue: 0,0:13:21.35,0:13:25.84,Default,,0000,0000,0000,,The microscope allows us to continue\Nour journey to the realm of the very small.
Dialogue: 0,0:13:27.32,0:13:29.49,Default,,0000,0000,0000,,As we move into the cell nucleus
Dialogue: 0,0:13:30.09,0:13:32.59,Default,,0000,0000,0000,,each new ring now reveals a world
Dialogue: 0,0:13:32.80,0:13:36.43,Default,,0000,0000,0000,,ten times smaller in diameter\Nthan the last.
Dialogue: 0,0:13:39.71,0:13:42.04,Default,,0000,0000,0000,,Deep within the nucleus
Dialogue: 0,0:13:42.11,0:13:44.84,Default,,0000,0000,0000,,we come upon\Ntruly remarkable constructions.
Dialogue: 0,0:13:45.72,0:13:49.05,Default,,0000,0000,0000,,Long, spiraling molecules of DNA.
Dialogue: 0,0:13:52.02,0:13:54.12,Default,,0000,0000,0000,,DNA holds the chemical codes
Dialogue: 0,0:13:54.19,0:13:57.32,Default,,0000,0000,0000,,for the reproduction of most organisms\Non the planet.
Dialogue: 0,0:13:57.83,0:14:01.82,Default,,0000,0000,0000,,Whether they're paramecia,\Npeople or petunias.
Dialogue: 0,0:14:09.28,0:14:11.71,Default,,0000,0000,0000,,Voyaging on, we see that molecules
Dialogue: 0,0:14:11.78,0:14:14.72,Default,,0000,0000,0000,,are made of even smaller parts\Ncalled atoms.
Dialogue: 0,0:14:20.99,0:14:24.19,Default,,0000,0000,0000,,The tiny world of the common atom\Nis very strange indeed.
Dialogue: 0,0:14:25.30,0:14:28.74,Default,,0000,0000,0000,,lts six electrons seem to swarm\Neverywhere at once.
Dialogue: 0,0:14:32.57,0:14:34.91,Default,,0000,0000,0000,,Now our voyage takes us through a void
Dialogue: 0,0:14:34.98,0:14:38.21,Default,,0000,0000,0000,,that appears as vast as the space\Nbetween the stars.
Dialogue: 0,0:14:39.68,0:14:42.08,Default,,0000,0000,0000,,Ahead lies the atomic nucleus.
Dialogue: 0,0:14:42.65,0:14:44.52,Default,,0000,0000,0000,,So fantastically small
Dialogue: 0,0:14:45.02,0:14:48.15,Default,,0000,0000,0000,,that if the whole atom\Nwere the size of this theater
Dialogue: 0,0:14:48.23,0:14:51.26,Default,,0000,0000,0000,,its nucleus would be like a speck of dust.
Dialogue: 0,0:14:52.70,0:14:56.33,Default,,0000,0000,0000,,Yet the nucleus contains\Nalmost all of the atom's mass
Dialogue: 0,0:14:56.91,0:14:59.27,Default,,0000,0000,0000,,packed into particles called protons
Dialogue: 0,0:14:59.61,0:15:00.98,Default,,0000,0000,0000,,and neutrons.
Dialogue: 0,0:15:02.75,0:15:07.65,Default,,0000,0000,0000,,And these, in turn, are made of smaller,\Nmore mysterious things called quarks.
Dialogue: 0,0:15:11.56,0:15:12.99,Default,,0000,0000,0000,,Exploring this
Dialogue: 0,0:15:13.19,0:15:15.32,Default,,0000,0000,0000,,the inner frontier of the universe
Dialogue: 0,0:15:15.40,0:15:18.02,Default,,0000,0000,0000,,physicists wonder\Nif quarks might contain
Dialogue: 0,0:15:18.10,0:15:20.57,Default,,0000,0000,0000,,even tinier building blocks of matter.
Dialogue: 0,0:15:28.11,0:15:33.08,Default,,0000,0000,0000,,Scientists are investigating this mystery\Nin an underground tunnel near Chicago
Dialogue: 0,0:15:33.72,0:15:37.02,Default,,0000,0000,0000,,home of the giant\NFermilab particle accelerator
Dialogue: 0,0:15:37.62,0:15:43.12,Default,,0000,0000,0000,,designed to create conditions\Nlike those after the birth of our universe.
Dialogue: 0,0:15:46.87,0:15:49.60,Default,,0000,0000,0000,,Millions of protons and antiprotons
Dialogue: 0,0:15:49.67,0:15:52.40,Default,,0000,0000,0000,,race through these pipes\Nin opposite directions
Dialogue: 0,0:15:52.48,0:15:57.04,Default,,0000,0000,0000,,nearly at the speed of light.\NA kind of subatomic demolition derby.
Dialogue: 0,0:16:26.05,0:16:29.99,Default,,0000,0000,0000,,Now our cosmic voyage\Nenters another dimension
Dialogue: 0,0:16:31.30,0:16:33.35,Default,,0000,0000,0000,,the dimension of time
Dialogue: 0,0:16:33.70,0:16:35.96,Default,,0000,0000,0000,,where knowledge is much less certain.
Dialogue: 0,0:16:36.80,0:16:39.90,Default,,0000,0000,0000,,Studying traces of quarks\Nfrom these collisions
Dialogue: 0,0:16:40.24,0:16:44.07,Default,,0000,0000,0000,,physicists try to learn\Nwhat our universe was like when it began
Dialogue: 0,0:16:44.14,0:16:47.27,Default,,0000,0000,0000,,after the explosion\Nknown as the Big Bang.
Dialogue: 0,0:16:50.28,0:16:52.34,Default,,0000,0000,0000,,One of them outlines the theory.
Dialogue: 0,0:16:53.26,0:16:54.81,Default,,0000,0000,0000,,Welcome to Fermilab.
Dialogue: 0,0:16:55.16,0:16:57.89,Default,,0000,0000,0000,,Today, astronomers\Nsee the universe expanding.
Dialogue: 0,0:16:58.03,0:17:00.46,Default,,0000,0000,0000,,lmagine running the expansion backwards.
Dialogue: 0,0:17:00.63,0:17:02.10,Default,,0000,0000,0000,,Billions of years ago
Dialogue: 0,0:17:02.17,0:17:05.47,Default,,0000,0000,0000,,everything must've been packed together\Nat enormous density.
Dialogue: 0,0:17:05.57,0:17:06.80,Default,,0000,0000,0000,,lt seems incredible
Dialogue: 0,0:17:06.91,0:17:08.53,Default,,0000,0000,0000,,but we think that the matter
Dialogue: 0,0:17:08.64,0:17:12.08,Default,,0000,0000,0000,,making up everything we see\Nin the universe
Dialogue: 0,0:17:12.48,0:17:16.47,Default,,0000,0000,0000,,the buildings, trees, people, planets
Dialogue: 0,0:17:16.72,0:17:19.31,Default,,0000,0000,0000,,stars out to the most distant galaxies
Dialogue: 0,0:17:19.92,0:17:23.92,Default,,0000,0000,0000,,was once crammed together\Ninto a volume smaller than this.
Dialogue: 0,0:17:24.83,0:17:26.06,Default,,0000,0000,0000,,And then.
Dialogue: 0,0:17:42.18,0:17:45.99,Default,,0000,0000,0000,,Space itself exploded,\Nin a burst of radiant energy.
Dialogue: 0,0:17:48.26,0:17:50.52,Default,,0000,0000,0000,,ln those first dazzling moments
Dialogue: 0,0:17:50.80,0:17:54.73,Default,,0000,0000,0000,,the newborn universe\Nbegan to expand and cool.
Dialogue: 0,0:17:56.14,0:17:58.83,Default,,0000,0000,0000,,Quarks combined\Ninto protons and neutrons
Dialogue: 0,0:17:59.47,0:18:02.77,Default,,0000,0000,0000,,which later attracted electrons\Nto form atoms
Dialogue: 0,0:18:03.75,0:18:06.48,Default,,0000,0000,0000,,and the vast fog lifted.
Dialogue: 0,0:18:21.04,0:18:22.97,Default,,0000,0000,0000,,For hundreds of millions of years
Dialogue: 0,0:18:23.04,0:18:27.07,Default,,0000,0000,0000,,the force of gravities slowly drew matter\Ntogether into a gigantic web.
Dialogue: 0,0:18:27.94,0:18:30.31,Default,,0000,0000,0000,,The architecture of the cosmos.
Dialogue: 0,0:18:36.79,0:18:38.76,Default,,0000,0000,0000,,Two billion years passed
Dialogue: 0,0:18:39.73,0:18:43.60,Default,,0000,0000,0000,,clouds of gas and dust condensed\Nlike giant water drops
Dialogue: 0,0:18:43.66,0:18:46.66,Default,,0000,0000,0000,,along the cosmic strands\Nand formed galaxies.
Dialogue: 0,0:18:59.95,0:19:02.25,Default,,0000,0000,0000,,Where the great ridges of matter crossed
Dialogue: 0,0:19:02.32,0:19:04.72,Default,,0000,0000,0000,,galaxies came together in clusters.
Dialogue: 0,0:19:30.12,0:19:33.03,Default,,0000,0000,0000,,Some galaxies evolved into gigantic discs
Dialogue: 0,0:19:33.40,0:19:36.09,Default,,0000,0000,0000,,and spirals of stars, gas, and dust.
Dialogue: 0,0:19:37.93,0:19:40.87,Default,,0000,0000,0000,,Neighboring galaxies trapped\Nby their mutual gravity
Dialogue: 0,0:19:41.37,0:19:44.17,Default,,0000,0000,0000,,draw together in the fantastic collision.
Dialogue: 0,0:19:45.48,0:19:48.31,Default,,0000,0000,0000,,ln real time, it would last a billion years.
Dialogue: 0,0:20:27.36,0:20:30.100,Default,,0000,0000,0000,,The force of gravities\Nstretch long tails of gas and stars
Dialogue: 0,0:20:31.10,0:20:32.93,Default,,0000,0000,0000,,from the huge new galaxy.
Dialogue: 0,0:20:36.08,0:20:38.14,Default,,0000,0000,0000,,And yet stars almost never collide
Dialogue: 0,0:20:39.25,0:20:41.61,Default,,0000,0000,0000,,so vast are the distances between them.
Dialogue: 0,0:20:52.06,0:20:54.26,Default,,0000,0000,0000,,Perhaps ten billion years pass
Dialogue: 0,0:20:54.97,0:20:57.13,Default,,0000,0000,0000,,and we encounter our own galaxy:
Dialogue: 0,0:20:57.30,0:20:58.70,Default,,0000,0000,0000,,The Milky Way.
Dialogue: 0,0:20:59.71,0:21:01.83,Default,,0000,0000,0000,,ln it, stars have formed
Dialogue: 0,0:21:02.94,0:21:04.67,Default,,0000,0000,0000,,and some have died.
Dialogue: 0,0:21:09.72,0:21:12.28,Default,,0000,0000,0000,,Stars are nuclear furnaces.
Dialogue: 0,0:21:12.49,0:21:14.98,Default,,0000,0000,0000,,They shine until they use up their fuel.
Dialogue: 0,0:21:15.36,0:21:17.99,Default,,0000,0000,0000,,Massive stars end explosively.
Dialogue: 0,0:21:32.68,0:21:35.71,Default,,0000,0000,0000,,These exploding stars, or supernovas
Dialogue: 0,0:21:36.52,0:21:38.58,Default,,0000,0000,0000,,send out the elements of life:
Dialogue: 0,0:21:38.96,0:21:42.36,Default,,0000,0000,0000,,The oxygen we breathe,\Nthe carbon in our muscles
Dialogue: 0,0:21:42.46,0:21:44.19,Default,,0000,0000,0000,,the iron in our blood.
Dialogue: 0,0:21:45.60,0:21:47.57,Default,,0000,0000,0000,,Now a cloud of cosmic gas
Dialogue: 0,0:21:47.80,0:21:51.40,Default,,0000,0000,0000,,sprinkled with these elements,\Ncomes together in the grip of gravity.
Dialogue: 0,0:21:57.35,0:22:00.61,Default,,0000,0000,0000,,A new star, our sun, ignites.
Dialogue: 0,0:22:03.72,0:22:05.71,Default,,0000,0000,0000,,Around it, planets form.
Dialogue: 0,0:22:08.60,0:22:12.26,Default,,0000,0000,0000,,ln their infancy,\Nover four billion years ago
Dialogue: 0,0:22:12.77,0:22:15.67,Default,,0000,0000,0000,,our Earth and moon\Nwere bombarded constantly
Dialogue: 0,0:22:15.74,0:22:18.10,Default,,0000,0000,0000,,by cosmic dust, asteroids
Dialogue: 0,0:22:19.48,0:22:20.70,Default,,0000,0000,0000,,and comets.
Dialogue: 0,0:23:16.32,0:23:19.62,Default,,0000,0000,0000,,With violent impacts and volcanic gases
Dialogue: 0,0:23:19.82,0:23:23.88,Default,,0000,0000,0000,,acid rain, and potent ultraviolet radiation\Nfrom the sun
Dialogue: 0,0:23:24.66,0:23:27.22,Default,,0000,0000,0000,,the young Earth was a very hostile world.
Dialogue: 0,0:23:30.80,0:23:34.67,Default,,0000,0000,0000,,And yet the basic ingredients\Nof life are already here.
Dialogue: 0,0:23:41.95,0:23:42.94,Default,,0000,0000,0000,,Water
Dialogue: 0,0:23:43.78,0:23:44.94,Default,,0000,0000,0000,,carbon
Dialogue: 0,0:23:45.75,0:23:47.31,Default,,0000,0000,0000,,and energy.
Dialogue: 0,0:23:50.63,0:23:54.100,Default,,0000,0000,0000,,Molecules, sheltered by the sea,\Nsomehow combined
Dialogue: 0,0:23:55.10,0:23:58.00,Default,,0000,0000,0000,,multiplied, and gave rise to life.
Dialogue: 0,0:23:58.44,0:24:03.10,Default,,0000,0000,0000,,For millions of years,\NEarth's only organisms were tiny bacteria.
Dialogue: 0,0:24:03.74,0:24:07.01,Default,,0000,0000,0000,,Some, called blue-green bacteria
Dialogue: 0,0:24:07.18,0:24:10.48,Default,,0000,0000,0000,,slowly released tiny bubbles of oxygen
Dialogue: 0,0:24:11.02,0:24:14.58,Default,,0000,0000,0000,,and profoundly changed the atmosphere.
Dialogue: 0,0:24:16.69,0:24:21.86,Default,,0000,0000,0000,,Above the clouds, some of this oxygen\Nformed a thin layer of ozone
Dialogue: 0,0:24:22.13,0:24:25.63,Default,,0000,0000,0000,,blocking most of the sun's\Nultraviolet rays.
Dialogue: 0,0:24:30.98,0:24:33.38,Default,,0000,0000,0000,,ln this changed environment
Dialogue: 0,0:24:33.65,0:24:36.55,Default,,0000,0000,0000,,new organisms flourished\Nin the Earth's waters.
Dialogue: 0,0:24:38.12,0:24:41.65,Default,,0000,0000,0000,,Colonies of green algae\Nproduced more oxygen.
Dialogue: 0,0:24:50.00,0:24:53.96,Default,,0000,0000,0000,,Then, organisms evolved\Nin an astonishing variety of forms.
Dialogue: 0,0:24:55.81,0:24:59.98,Default,,0000,0000,0000,,Some with shells or skeletons\Nfor protection and support.
Dialogue: 0,0:25:10.03,0:25:14.99,Default,,0000,0000,0000,,Others evolved complex life cycles,\Nlike this tiny crustacean.
Dialogue: 0,0:25:16.44,0:25:21.54,Default,,0000,0000,0000,,The shallow waters of the seas\Nfilled with a teaming diversity of life forms.
Dialogue: 0,0:25:34.73,0:25:39.43,Default,,0000,0000,0000,,Life's next challenge\Nwas to colonize the harsh, dry land.
Dialogue: 0,0:25:42.94,0:25:47.90,Default,,0000,0000,0000,,Bacteria were first, followed by algae,\Nplants, and animals.
Dialogue: 0,0:26:13.38,0:26:17.87,Default,,0000,0000,0000,,Vertebrates appeared on land,\Nfeeding on both plants and animals
Dialogue: 0,0:26:19.58,0:26:23.25,Default,,0000,0000,0000,,and gave rise to larger\Nand larger life forms.
Dialogue: 0,0:26:26.86,0:26:29.42,Default,,0000,0000,0000,,Some of them conquered\Nthe realm of the air
Dialogue: 0,0:26:30.63,0:26:33.73,Default,,0000,0000,0000,,and others, the great open plains.
Dialogue: 0,0:26:54.20,0:26:58.10,Default,,0000,0000,0000,,Our cosmic voyage, from the Big Bang\Nto the appearance of humans
Dialogue: 0,0:26:58.17,0:27:01.19,Default,,0000,0000,0000,,took about 15 billion years.
Dialogue: 0,0:27:03.01,0:27:05.77,Default,,0000,0000,0000,,From the beginning, we were explorers
Dialogue: 0,0:27:06.34,0:27:09.21,Default,,0000,0000,0000,,inventors and technicians.
Dialogue: 0,0:27:17.86,0:27:22.23,Default,,0000,0000,0000,,And in a few thousand years,\Njust an instant in cosmic time
Dialogue: 0,0:27:22.70,0:27:27.57,Default,,0000,0000,0000,,curiosity and technology\Nwould take us back toward the stars.
Dialogue: 0,0:27:57.74,0:27:59.91,Default,,0000,0000,0000,,Since it was launched into orbit
Dialogue: 0,0:28:00.08,0:28:02.78,Default,,0000,0000,0000,,the Hubble space telescope\Nhas captured images
Dialogue: 0,0:28:02.85,0:28:05.08,Default,,0000,0000,0000,,that reveal ever more beautiful
Dialogue: 0,0:28:05.15,0:28:09.42,Default,,0000,0000,0000,,and mysterious regions of the universe,\Nwhere stars are dying out.
Dialogue: 0,0:28:13.90,0:28:15.80,Default,,0000,0000,0000,,And within the Eagle Nebula
Dialogue: 0,0:28:15.97,0:28:20.27,Default,,0000,0000,0000,,strange towers of glowing gas\Nare giving birth to new stars.
Dialogue: 0,0:28:22.54,0:28:24.53,Default,,0000,0000,0000,,ln the great Orion Nebula
Dialogue: 0,0:28:24.61,0:28:29.74,Default,,0000,0000,0000,,discs of dust seem to be turning\Ninto solar systems just like our own.
Dialogue: 0,0:28:33.69,0:28:37.96,Default,,0000,0000,0000,,The grand adventure of cosmic exploration\Nis accelerating rapidly
Dialogue: 0,0:28:38.20,0:28:42.06,Default,,0000,0000,0000,,taking us into realms\Nthat once were the stuff of science fiction
Dialogue: 0,0:28:42.40,0:28:45.34,Default,,0000,0000,0000,,like the mysterious black hole.
Dialogue: 0,0:28:50.85,0:28:55.04,Default,,0000,0000,0000,,Here, a red giant star\Nis slowly being consumed
Dialogue: 0,0:28:55.22,0:28:58.92,Default,,0000,0000,0000,,its gases swirling into the depths\Nof a black hole.
Dialogue: 0,0:29:03.60,0:29:07.93,Default,,0000,0000,0000,,Some black holes may be collapsed cores\Nof very massive stars
Dialogue: 0,0:29:08.30,0:29:12.47,Default,,0000,0000,0000,,with gravity so powerful\Nnot even light can escape them.
Dialogue: 0,0:29:13.01,0:29:17.47,Default,,0000,0000,0000,,But they can be detected from their trap\Nand swallow nearby stars.
Dialogue: 0,0:29:27.39,0:29:29.56,Default,,0000,0000,0000,,For the first time in our history
Dialogue: 0,0:29:29.63,0:29:34.16,Default,,0000,0000,0000,,we now have strong evidence\Nthat there are planets orbiting other stars.
Dialogue: 0,0:29:35.90,0:29:40.36,Default,,0000,0000,0000,,Scientists think there could be millions\Nof earth-like planets in our galaxy alone.
Dialogue: 0,0:29:44.62,0:29:47.71,Default,,0000,0000,0000,,lf so, do any of them have life?
Dialogue: 0,0:29:52.59,0:29:54.79,Default,,0000,0000,0000,,Some radio telescopes search for signals
Dialogue: 0,0:29:54.90,0:29:58.13,Default,,0000,0000,0000,,that may reveal the presence\Nof alien civilizations.
Dialogue: 0,0:29:59.80,0:30:01.29,Default,,0000,0000,0000,,lt's a daunting task.
Dialogue: 0,0:30:02.07,0:30:05.17,Default,,0000,0000,0000,,But, if one day we should receive a signal
Dialogue: 0,0:30:05.71,0:30:08.64,Default,,0000,0000,0000,,it would forever change our view\Nof ourselves
Dialogue: 0,0:30:09.31,0:30:10.98,Default,,0000,0000,0000,,and our universe.
Dialogue: 0,0:30:36.32,0:30:40.25,Default,,0000,0000,0000,,Telescopes, such as the giant\NKeck Observatory in Hawaii
Dialogue: 0,0:30:40.49,0:30:43.65,Default,,0000,0000,0000,,are like time machines\Ncapturing the faint light
Dialogue: 0,0:30:43.72,0:30:47.16,Default,,0000,0000,0000,,that has traveled towards us\Nthrough all of cosmic history.
Dialogue: 0,0:30:48.03,0:30:52.97,Default,,0000,0000,0000,,The deeper astronomers look into space,\Nthe farther back they see in time.
Dialogue: 0,0:31:09.42,0:31:11.76,Default,,0000,0000,0000,,The more we learn about the universe
Dialogue: 0,0:31:12.29,0:31:14.63,Default,,0000,0000,0000,,the more new mysteries we uncover
Dialogue: 0,0:31:15.16,0:31:20.26,Default,,0000,0000,0000,,profound questions for future generations\Nof cosmic explorers.
Dialogue: 0,0:31:23.98,0:31:27.34,Default,,0000,0000,0000,,Will the universe go on expanding forever?
Dialogue: 0,0:31:28.18,0:31:30.62,Default,,0000,0000,0000,,Exactly how did life arise?
Dialogue: 0,0:31:31.55,0:31:35.12,Default,,0000,0000,0000,,Could there be other universes\Nbeyond our cosmic horizon?
Dialogue: 0,0:31:35.92,0:31:38.90,Default,,0000,0000,0000,,And are there others\Nelsewhere in the universe
Dialogue: 0,0:31:39.10,0:31:40.100,Default,,0000,0000,0000,,asking the same things?
Dialogue: 0,0:31:41.80,0:31:45.24,Default,,0000,0000,0000,,Even to ask such questions is ambitious.
Dialogue: 0,0:31:45.97,0:31:49.30,Default,,0000,0000,0000,,But look how far we've traveled\Nsince our ancestors
Dialogue: 0,0:31:49.38,0:31:52.87,Default,,0000,0000,0000,,took the first steps in our cosmic voyage.
Dialogue: 0,0:33:30.04,0:33:34.64,Default,,0000,0000,0000,,Man must understand his universe\Nin order to understand his destiny.
Dialogue: 0,0:33:35.98,0:33:39.68,Default,,0000,0000,0000,,Who knows what mysteries\Nwill be solved in our lifetime
Dialogue: 0,0:33:40.05,0:33:44.35,Default,,0000,0000,0000,,and what new riddles will become\Nthe challenge of the new generations?