#CarlSagan covers a wide range of scientific subjects, including the origin of life and a #perspective of our place in the universe...
A 13-part #documentary #series that covers a wide range of #scientific #subjects, including the #origin of #life and a #perspective of our place in the universe narrated by famous American #Scientist – #Carl #Sagan.
A 13-part #documentary #series that covers a wide range of #scientific #subjects, including the #origin of #life and a #perspective of our place in the universe narrated by famous American #Scientist – #Carl #Sagan.
Category
📚
LearningTranscript
00:00:00Oh
00:00:30Imagine that we are travelers from the stars.
00:01:00Bound for the sun, we would discover it surrounded by four giant cloudy gas worlds, blue Neptune
00:01:09and its frozen moon Triton, and then farther in Uranus and its dark rings made perhaps
00:01:20of organic matter.
00:01:29Saturn, the jewel of the solar system, set within concentric rings composed of a billion icy
00:01:49moons.
00:02:03And finally, flanked by massive satellites, the largest planet, Jupiter.
00:02:12Its multicolored clouds studded with flashes of lightning.
00:02:22Still farther in, closer to the sun, there are no more giant planets.
00:02:30Only a host of lesser worlds made of rock and metal, some with a thin envelope of air.
00:02:40They huddle about the sun with almost no internal heat of their own.
00:02:45Tiny places with solid surfaces, one of which is a blue and pretty world called Earth.
00:02:55Half covered with clouds, it is the home planet of travelers who have just learned to sail the
00:03:01sea of space to investigate, close up, Jupiter, Saturn, Uranus and Neptune, its brothers and
00:03:09sisters in the family of the sun.
00:03:20Human voyages of exploration to the outer solar system are controlled, so far, from a single
00:03:27place on the planet Earth, the Jet Propulsion Laboratory of the National Aeronautics and Space
00:03:32Administration in Pasadena, California.
00:03:39Here, on Sunday, July 8, 1979, the Voyager 2 spacecraft began its close passage by Jupiter and
00:03:50its moons.
00:03:51The spacecraft had been instructed how to explore the Jupiter system by a sequence of
00:04:07commands radioed earlier to its onboard computers.
00:04:08Power, 450 watts.
00:04:09Power is going.
00:04:10DSE systems.
00:04:11DSE.
00:04:12Okay.
00:04:13LACP mode is far and counter.
00:04:14We are at tick 210.
00:04:15The direction last recorded was reversed and the track is track one.
00:04:28Here we check how faithful an emissary Voyager is.
00:04:31Does it understand the commands?
00:04:32How is its health, its temperature, its brains, its heart?
00:04:38The modern ships that sail to the planets are unmanned.
00:04:54They are beautifully constructed, semi-intelligent robots.
00:05:01Voyager's eyes are two television cameras designed to take tens of thousands of pictures
00:05:07in the outer solar system.
00:05:08Along with other instruments, they are mounted on a scanned platform which points at passing
00:05:14planets.
00:05:15Voyager's brains are three integrated computers set amidships.
00:05:20It communicates with Earth through a large radio antenna mounted like a sail.
00:05:26Voyager bears a message for any alien civilization it may one day encounter in interstellar space.
00:05:33Its louvers open and shut to help control the onboard temperature.
00:05:39But Voyager cruises so far from the sun that it cannot depend on solar power.
00:05:44Instead, it has a small nuclear power plant quarantined from the rest of the ship.
00:06:01But things can go wrong in such pioneering missions.
00:06:04So people are a little uneasy at Voyager mission control.
00:06:08Jupiter is surrounded by a shell of invisible but extremely dangerous high energy charged particles.
00:06:15If Voyager flies too close, its delicate electronics will be fried.
00:06:20A collision with a small boulder in the rings of Jupiter could send the spacecraft tumbling wildly out of control.
00:06:27Its antennae unable to find the Earth, its data lost forever.
00:06:36Voyager 1 and Voyager 2 were launched a month apart in late summer 1977.
00:06:42After many alarms and close calls, they successfully arrived months apart at the Jupiter system.
00:06:49Where they worked brilliantly providing the first close-up views of mighty Jupiter and its four large and mysterious moons.
00:06:58Io, the innermost of the four.
00:07:01Europa, and moving away from Jupiter, Ganymede.
00:07:08And the outermost big moon, Callisto.
00:07:17A mission that cost a penny a world for every human on the planet Earth.
00:07:27Voyager's passage by Jupiter accelerated it towards a close encounter with the planet Saturn.
00:07:37Saturn's gravity will propel it on to Uranus.
00:07:40And in this game of cosmic billiards after Uranus, it will plunge on past Neptune, leaving the solar system and becoming an interstellar spacecraft.
00:07:50Destined to wander forever in the great ocean between the stars.
00:07:57And if Voyager should sometime in its distant future encounter beings from some other civilization in space, it bears a message.
00:08:07A phonograph record, golden, delicate, with instructions for use.
00:08:15And on this record are a sampling of pictures, sounds, greetings, and an hour and a half of exquisite music.
00:08:22The Earth's greatest hits.
00:08:25A gift across the cosmic ocean from one island of civilization to another.
00:08:32The record bears, in English, an additional little handwritten reading that says,
00:08:40To the makers of music, all worlds, all times.
00:08:45These voyages of exploration and discovery are the latest in a long series which have characterized and distinguished the human species.
00:08:55In the 15th and 16th centuries, you could travel from Spain to the Azores in a few days.
00:09:02The same time it takes now to cross that little channel from the Earth to the Moon.
00:09:08It took then a few months to traverse the Atlantic Ocean and reach what was called the New World, the Americas.
00:09:15Today, it takes a few months to cross the ocean of the inner solar system and reach Mars and Venus, which are truly and literally New World's awaiting us.
00:09:26In the 17th and 18th centuries, you could travel from Holland to China, say, in a year or two.
00:09:32The same time it takes now for Voyager to travel from the Earth to Jupiter.
00:09:37And in comparison to the resources of the society, it cost more then to send sailing ships to the Far East than it does now to send spaceships to the planets.
00:09:56The passion to explore is at the heart of being human.
00:10:01This impulse to go, to see, to know, has found expression in every culture.
00:10:08Africa was circumnavigated by Phoenician sailors in the employ of an Egyptian pharaoh in the 7th century BC.
00:10:19The islands of the Pacific were settled by skilled and heroic navigators from Indonesia.
00:10:26Great fleets of ocean-going junks left the ports of Ming Dynasty China to explore India and Africa.
00:10:35A century later, three ships left Spain under the command of an Italian navigator to discover the Americas.
00:10:44And then a Portuguese expedition succeeded in sailing all the way around this blue globe.
00:10:51These Voyagers, of many cultures, were the first planetary explorers.
00:10:57They have bound the Earth up into one world.
00:11:00In our exploration of other worlds, we follow in their footsteps.
00:11:05Our present spaceships are the harbingers, the vanguard of future human expeditions to the planets.
00:11:16We have traveled this way before.
00:11:19And there is much to be learned by studying those great voyages of a few centuries ago.
00:11:26In the 17th century, the citizens of the new Dutch Republic pursued a course of vigorous planetary exploration.
00:11:49Holland was then a revolutionary society.
00:11:54It had just declared its independence from the powerful but stagnant Spanish Empire.
00:11:59And with a newfound self-confidence, Holland embraced, more fully than any other nation of its time, the spirit of the European Enlightenment.
00:12:12It was a rational, orderly, and creative society.
00:12:17But because Spanish ports and vessels were closed to the Dutch, the economic survival of the tiny Republic depended on its ability to construct, man, and operate a great fleet of commercial sailing vessels.
00:12:31The Dutch East India Company was a combined governmental and commercial enterprise which sent shipping to the far corners of the world to acquire rare commodities and resell them at a profit in Europe.
00:12:48Such voyages were the life's blood of the Republic.
00:12:51Navigational charts and maps were classified as state secrets.
00:13:00Ships sometimes left with sealed sailing orders, the crews embarking for an unknown destination more than a year away on the far side of the planet.
00:13:10These expeditions were not only commercial exploitations, although there was certainly plenty of that.
00:13:19Besides the usual appeals of ambition, greed, national pride, and the thirst for adventure, the Dutch were also motivated by a powerful scientific curiosity and a fascination with all things new.
00:13:32New lands, new peoples, new plants and animals.
00:13:37This building, then the Amsterdam Town Hall, still attests to the hardy self-assurance of its 17th century architects.
00:13:52Its lavish crystal adornments still reflect the glittering pride they felt in their accomplishments and their prosperity.
00:14:00It took shiploads of marble to build this place.
00:14:04Constantine Huygens, a poet and diplomat of the time, said that this town hall dispelled what he called the Gothic squint and squalor.
00:14:15The Middle Ages had ended.
00:14:19The Enlightenment had begun.
00:14:21Up there, do you see, is Atlas supporting the heavens on his shoulders.
00:14:33And beneath is Justice with a golden sword and golden scales, flanked by death and punishment.
00:14:46And who is it that justice is trampling underfoot?
00:14:51Why, it's avarice and envy.
00:14:55The gods of the merchants.
00:14:58The Dutch knew that the unrestrained pursuit of profit posed serious threats to the soul of the nation.
00:15:07A less allegorical symbol is down here on the floor.
00:15:16It is a great inlaid map stretching from West Africa to the Pacific Ocean.
00:15:24The whole world was then Holland's arena.
00:15:28In a typical year, many sailing vessels set out halfway around the world for the Far East on voyages of exploration and discovery of trade journeys taking years to accomplish down the west coast of Africa through what they call the Ethiopian Sea, skirting the southern coast of Africa through the straits of Madagascar and on past the southern tip of India.
00:15:57From India to the Spice Islands, present day Indonesia.
00:16:08Another set of voyages went south and east to New Holland, later renamed Australia.
00:16:15And still other journeys ventured through the straits of Malacca to the empire of China.
00:16:28But Holland was a small country forced to live by its wits.
00:16:33There was a strong pacifist element in its foreign policy.
00:16:37Never before or since has Holland boasted such a galaxy of scientists, mathematicians, philosophers and artists.
00:16:45This was the time of the great painters, Rembrandt and Vermeer.
00:16:52Because Holland was tolerant of unorthodox opinions, it was a refuge for intellectuals fleeing the thought control and censorship of other parts of Europe.
00:17:07Much as the United States benefited enormously in the 1930s from the exodus of intellectuals from Nazi dominated Europe.
00:17:16And so it was that 17th century Holland was the home of the great Jewish philosopher Spinoza, who Einstein admired so much.
00:17:25Of René Descartes, a pivotal figure in the history of philosophy and of mathematics.
00:17:31And the home of a political scientist named John Locke, who was to have a powerful and profound influence on a group of philosophically inclined revolutionaries named Payne, Hamilton, Adams, Franklin and Jefferson.
00:17:52The Dutch University of Leiden offered a professorship to an Italian scientist named Galileo, who had been forced by the Catholic Church under threat of torture to recant the heretical position that the earth went around the sun and not vice versa.
00:18:15Galileo had close ties with Holland. His first astronomical telescope was based on a spyglass of Dutch manufacture. And with it, he discovered the craters of the moon, the phases of Venus and the four large moons of Jupiter.
00:18:32Becoming an exploratory power made Holland a vital intellectual and cultural center as well. The improvement of sailing ship technology spurred technology in general.
00:18:47A key problem in navigation was the determination of longitude. Latitude could be determined easily. The farther south you were, the more southern constellations you could see.
00:18:57But longitude required precise time keeping. An accurate shipboard clock would continue to keep the time in your home port. The rising and setting of the stars would give you the local time. And the difference between the two would tell you how far east or west you had gone.
00:19:15Technological advance required the freest possible pursuit of knowledge. So Holland became the leading publisher and bookseller in Europe, translating works written in other languages and printing books that had been censored elsewhere.
00:19:34Adventures into exotic lands and encounters with strange societies shook complacency.
00:19:44They challenged the prevailing wisdom and showed that ideas which had been accepted for thousands of years might be fundamentally in error.
00:19:53In a time when kings and emperors ruled much of the planet, the Dutch Republic was governed more than any other world power by the people.
00:20:13They enjoyed a certain material well-being. But the interiors of their houses, celebrated by a generation of Dutch painters, suggest restraint and discretion.
00:20:32The officers of these ships of exploration and trade would return from their long voyages, share in the goods they had acquired and discuss the wonders they had encountered.
00:20:51Holland prospered in its freedom of thought.
00:21:16In Italy, Galileo had announced other worlds. Giordano Bruno had speculated on intelligent life elsewhere. For this, they were made to suffer brutally.
00:21:29But in Holland, the astronomer Christian Huygens, who strongly supported both ideas, was showered with honors.
00:21:39Christian was the son of Constantine Huygens.
00:21:44The elder Huygens distinguished himself as a master diplomat of the age, a man of letters, a close friend and translator of the English poet John Donne.
00:21:57Constantine Huygens was also an accomplished composer and musician.
00:22:04It was Constantine who had discovered a young painter named Rembrandt van Rijn, in several of whose works he subsequently appears.
00:22:23He opened the doors of his house to artists, musicians, writers, statesmen, and scientists.
00:22:30A feast of goods and ideas from all over the world awaited them.
00:22:36The philosopher Descartes, who visited him here, said of Constantine Huygens,
00:22:43I could not believe that a single mind could occupy itself with so many things and acquit itself so well in all of them.
00:22:53He even excelled at the art of parenthood.
00:22:56He was a tender and loving father.
00:22:59His son, Christian, flourished in this rich environment, demonstrating extraordinary talents for languages, drawing, law, science, engineering, mathematics, and music.
00:23:10The world is my country, he said. Science, my religion.
00:23:25Light was the motif of the age, the symbolic enlightenment of freedom of thought and religion,
00:23:33the light that suffused the paintings of the time and light as an object of scientific study.
00:23:40The microscope was invented in Holland at this time and became a drawing room curiosity.
00:23:48Its inventor was a friend of Christian Huygens, a man named Anton Leeuwenhoek.
00:24:02The first microscopes were developed from magnifying glasses used by drapers to examine the quality of cloth.
00:24:17Leeuwenhoek and Huygens are the grandfathers of much of modern medicine.
00:24:22Because, to his amazement, Leeuwenhoek discovered a universe in a drop of water.
00:24:31The microbes, which he described as animalcules, and thought cute.
00:24:37Leeuwenhoek and Huygens were among the first people to see human sperm cells, a hitherto hidden microcosm of the human life cycle.
00:24:54Leeuwenhoek had discovered the microbial world.
00:24:59Huygens had argued, from his telescopic observations, that Mars was another world, and probably an inhabited one.
00:25:08What a waste of a planet, he thought, if Mars were barren.
00:25:18So the Viking search for microbes on Mars can be traced directly back to Huygens and Leeuwenhoek in 17th century Holland.
00:25:33The telescope and the microscope developed here represent an extension of human vision to the realms of the very small and the very large.
00:25:48Our observations of atoms and galaxies were launched in this time and place.
00:26:02From the bending of light through a lens, Huygens advanced the idea that light was a kind of wave.
00:26:09He ground and polished lenses for the successively larger telescopes he constructed.
00:26:15Although, it did take him a time to figure out how to use them properly.
00:26:30Huygens was the first person to see a surface feature on the planet Mars.
00:26:35He was the first person to speculate that Venus is completely covered with clouds.
00:26:40He was the first person to understand the nature of the rings of Saturn.
00:26:45Saturn is surrounded, he wrote, by a thin, flat ring, which nowhere touches the body of the planet.
00:26:51His discoveries with the telescope would, by themselves, have ensured his place in the history of human accomplishment.
00:27:09Huygens was the discoverer of Titan, the largest moon of Saturn.
00:27:23The immense size and changing clouds of Jupiter entranced him.
00:27:41Astronomers, as well as navigators, need accurate clocks to time the movement of the heavens.
00:27:46Huygens was the inventor of many precision timepieces, including the pendulum clock.
00:27:52To illustrate the sun-centered universe of Copernicus, he built computers that reproduced the clockwork of the heavens, from Mercury to Saturn.
00:28:10The machines he designed, he designed, he designed.
00:28:20Christian Huygens, inventor.
00:28:22He was delighted that the Copernican system was widely accepted in everyday life in Holland,
00:28:31and acknowledged by all astronomers except those, he wrote,
00:28:35who were a bit slow-witted or under the superstitions imposed by merely human authority.
00:28:40Across the sea of space, the stars are other suns.
00:28:53A point which Huygens appreciated perfectly well.
00:28:57He reasoned that if our planetary system involved a sun and planets going around it,
00:29:05that those other suns should likewise have a retinue of planets going around them,
00:29:12and also that many of the other planets were inhabited.
00:29:16He set forth these conclusions in a remarkable book bearing the triumphant title,
00:29:24The Celestial Worlds Discovered.
00:29:27The subtitle is Conjectures Concerning the Inhabitants, Plants, and Productions of the Worlds in the Planets.
00:29:41He wrote this book sometime shortly before his death in the year 1690 in this study.
00:29:49By and large, Huygens imagined that the environments of the other planets,
00:30:02and also the inhabitants of the other planets, were pretty much like those of 17th century Europe.
00:30:08I wonder if he imagined traveling to those other worlds which he had been the first to examine close up to the telescope.
00:30:19Perhaps he dreamt that voyages of discovery to the planets would one day be rather like the voyages of geographical discovery in his time and place.
00:30:29He did imagine of extraterrestrial beings that their whole bodies and every part of them may be quite distinct and different from ours.
00:30:43Tis a very ridiculous opinion, he says, that it is impossible a rational soul should dwell in any other shape than ours.
00:30:52You could be smart, Huygens was saying, even if you looked funny.
00:30:57But he then went on to argue that they didn't look all that funny.
00:31:02That extraterrestrial beings must have hands and feet and stand upright and have writing and geometry.
00:31:09And even that the four big moons of Jupiter, the Galilean satellites, were there in order to provide a navigational aid, a convenience for the sailors in the Jovian oceans.
00:31:23Well, maybe.
00:31:24Maybe.
00:31:32That bit of speculation is probably wrong.
00:31:36But think of a citizen of the 17th century with the courage and insight to imagine other landscapes and other intelligences.
00:31:46Might there really be mariners on a million other worlds?
00:31:54In his book, Huygens wrote, what a wonderful and amazing scheme have we here of the magnificent vastness of the universe.
00:32:04So many suns, so many Earths, and every one of them stocked with so many animals, adorned with so many seas.
00:32:14How must our wonder and admiration be increased when we consider the prodigious distance and multitude of the stars?
00:32:23The Dutch call their ships flying boats.
00:32:34And the Voyager spacecraft are their descendants.
00:32:38True flying boats bound for the stars and on the way exploring some of those worlds which Christian Huygens, a man from Earth, knew and loved so well.
00:32:50Travelers tales.
00:32:54One of the main commodities returned by those sailing ship voyages of centuries ago were stories.
00:33:01Stories of alien lands and exotic creatures.
00:33:06They evoked the sense of wonder and stimulated further exploration.
00:33:15Those tales of strange worlds enabled some Europeans to see themselves anew.
00:33:20There had been accounts of headless people, foot people, cyclops people.
00:33:28Now, the Dutch brought back fantastic stories of giant hunters, dodos, rhinos, leopards, and other creatures.
00:33:43Modern Voyagers also return travelers tales.
00:33:51Tales of a world shattered like a crystal sphere.
00:33:56A place where the ground is covered with what looks like a network of giant cobwebs.
00:34:03A world with an underground ocean.
00:34:11Tiny moons shaped like potatoes.
00:34:15A yellow and red pockmarked land with lakes of molten sulfur and volcanic eruptions 300 kilometers high.
00:34:24And a place called Jupiter.
00:34:31So large that a thousand Earths would fit inside.
00:34:34There are no mountains, valleys, volcanoes, or rivers there.
00:34:38Just a vast ocean of gas and clouds.
00:34:41Everything we see on Jupiter is floating in the sky.
00:34:43But there is much that is fascinating about Jupiter.
00:34:51As the solar system condensed out of interstellar gas and dust.
00:34:55Jupiter acquired most of the matter that wasn't ejected into interstellar space and which didn't fall inwards to form the Sun.
00:35:03Jupiter is made mostly of hydrogen and helium, just like the Sun.
00:35:07And had Jupiter been a few dozen times more massive, the matter in it might have undergone thermonuclear reactions in the interior.
00:35:19And Jupiter would have begun to shine by its own light.
00:35:23Jupiter is a star that failed.
00:35:28Had it become a star, we would be living in a double star system with two suns in our sky.
00:35:34And the nights would come more rarely.
00:35:38Deep below the clouds of Jupiter, the weight of the overlying layers of atmosphere produce pressures which are much greater than any that are found anywhere on the Earth.
00:35:49The clouds are just this little layer here.
00:35:51The deep interior is this high pressure place.
00:35:53The pressure is so large that electrons are squeezed off hydrogen atoms.
00:36:00Producing liquid metallic hydrogen.
00:36:06But at the very core of Jupiter, there may be a lump of rock and iron.
00:36:12A giant, Earth-like world under astonishing pressures hidden forever at the center of the largest planet.
00:36:21Just before a Voyager encountered Jupiter, you could see that giant planet at night shining in the sky as our ancestors have for the last million years.
00:36:35And on my way to study the Voyager data arriving here at the Jet Propulsion Laboratory, I thought that Jupiter would never be the same again.
00:36:45Never again just a point of light in the night sky.
00:36:49But forever after, a place to be explored and known.
00:36:53To see the first close-up images of a world never before known, this moment is one of the greatest joys in the life of a planetary scientist.
00:37:07In the early morning hours of July 9, 1979, on the real-time television monitors at the Jet Propulsion Laboratory, we began to learn about a world called Europa.
00:37:17Yeah.
00:37:18These are the modern explorers, men and women trained in astronomy, physics, geology, or engineering.
00:37:26Many of them have devoted five to eight years to this single mission.
00:37:30The model for Europa says that if you started off with it liquid, you could probably pump in enough energy to keep it liquid.
00:37:37The Kasen thing said that in order for there to be enough heating going on, you sort of had to start the heating before Europa basically cooled off.
00:37:45Yeah, but Gene, what about the relief from the cracks? Shouldn't the cracks and yield and flow also?
00:37:50They've got to be, they've got to be redeemed.
00:37:52In the aisle in Europa, there's a twin, a pair there, and then there's a pair out of Yammy's ballistic.
00:37:57You can't look at the surface of a world so different from ours without wondering how both were made.
00:38:03Just rotate it out a little bit.
00:38:06Voyager presented us with six new worlds in the Jupiter system alone.
00:38:10Maybe.
00:38:11The more you learn about other worlds, the better you understand our own.
00:38:16We speculate, criticize, argue, calculate, reflect, and wonder.
00:38:21We return again and again to the astonishing data.
00:38:24And slowly, we begin to understand.
00:38:26The Dutch sailing ships brought back rare and valuable commodities from the new worlds they visited.
00:38:43Our Voyager spaceships return rare and valuable information to computerized wharves on this shore of the sea of space.
00:38:53Here, the data are unloaded to be stored, enhanced, processed, and treasured.
00:38:59Maps of alien lands will be generated from this information.
00:39:02In this electronic warehouse are tens of thousands of images of previously unknown worlds.
00:39:12How does a picture from the outer solar system get to us?
00:39:16Sunlight shines on Europa and is reflected back to space, where some of it strikes the phosphors of the Voyager television cameras generating an image.
00:39:24The image is radioed back across the immense intervening distance of half a billion kilometers to a radio telescope on Earth, one in Australia, say.
00:39:34The telescope then passes the information via communications satellite in Earth orbit to Southern California.
00:39:42There, it's transmitted by a set of microwave relay towers to a computer at the Jet Propulsion Laboratory.
00:39:49And there, it is processed.
00:40:00The picture is fundamentally like a newspaper wire photo, made of perhaps a million individual dots of differing shades of gray,
00:40:08so fine and close together that, at a distance, the constituent dots are invisible.
00:40:14We see only their cumulative effect.
00:40:16The information from the spacecraft specifies how bright or dark each dot is to be.
00:40:22After processing, the dots are then stored on a magnetic disc, something like a phonograph record.
00:40:28By this day, there were already 11,000 pictures from Voyager 2 in our electronic library.
00:40:33Finally, the end product of this remarkable set of links and relays is a hard copy which comes out of this machine showing, in this case, the wonders of Europa, which were recorded for the first time in human history today.
00:40:51It is absolutely astonishing.
00:40:57See, Voyager 1 got very good pictures of the other three big moons, Galilean satellites of Jupiter, but not of Europa.
00:41:05It was left to Voyager 2 today to get the first close-up pictures of Europa where we see things that are only a few kilometers across.
00:41:15And at first glance, it looks like nothing so much as the canal network of Mars that Percival Lowell imagined to exist on that planet.
00:41:26We see an amazing, intricate network of criss-crossing straight and curved lines.
00:41:32Are these straight lines rigid? Are they troughs? Is it connected with plate tectonics on the Earth? How does it illuminate the other satellites of the Jovian system?
00:41:45At this moment, the vaunted technology has produced something astonishing, but it remains for the limitations and cleverness of another device, the human brain, to figure it out.
00:42:00Fortunately, we have plenty of pictures to help us.
00:42:08What about Gene's idea of geysers down the troughs?
00:42:13Geysers down the troughs? Well, you've got to have a mechanism to drive it.
00:42:18Larry Soderlund, Voyager imaging team.
00:42:21Some wild idea a few months ago that we might have sort of champagne bottle models.
00:42:28And what that is is you seal the crust and you have liquid underneath that solid crust.
00:42:33The question is, do you have that kind of condition which is an explosive...
00:42:37Lonnie Lane, deputy project scientist.
00:42:39You have a large area and I thought you'd have enough resolution with some of these pictures that you don't see something that is spread laterally.
00:42:47Do we have the high resolution piece to look?
00:42:50Yeah, it was here somewhere.
00:42:52There it is. This is where we pick out the relief and if we're going to see the things we can recognize.
00:42:56Weeks after the pictures from Europa were received, we were still debating what was in them.
00:43:03It's as if we almost got to the, here's another thing, look at the little mesas here.
00:43:08We almost got to the limit of resolution required to see the craters, the craters which would last indefinitely on a crust this thing.
00:43:15Apart from the Rousseau's, there's a set of very fine small dot markings which are mostly in the model terrain.
00:43:24Yeah, like those guys.
00:43:26Now, do you think those are sites of outgassing, calderas, fumaroles, sulfateras?
00:43:32I don't know, but I'll tell you one thing I just picked up. Let's look at this.
00:43:35Here.
00:43:37Look right here.
00:43:40It disappeared.
00:43:41Look right here.
00:43:42Oh, yeah, that's all.
00:43:43You see a central peak?
00:43:44Yep, yep.
00:43:45You see a little hole?
00:43:46A little hole.
00:43:47Yep, it's a, I don't see a radial there.
00:43:49You can tell there.
00:43:50I think it's got to be an impact craters. Look at the central peak on it.
00:43:52There's almost no impact craters on this planet.
00:43:54Wait, wait, wait. We just found one.
00:43:56Almost none.
00:43:58Therefore, finding one which is alleged to be the exception, maybe it's not the exception, but something else.
00:44:06Perhaps, but on the other hand, you asked about all those little holes that we can't quite make out.
00:44:10So you'd argue that the resolution would be dead on these.
00:44:13The big craters go away by some rheological deformation, and the little ones stay, but they're just at the edge of our resolution.
00:44:19That's because they're one-tenth the depth of the solid, the rigid crust.
00:44:23Well, maybe.
00:44:24Computer processing of the pictures has revealed at least a few features on Europa, which seem to be impact craters, but something has wiped out the big craters.
00:44:35Computer processing also played a major role in one of the most amazing Voyager discoveries made on the moon next door to Europa, a world called EO.
00:44:43Even from Earth, we could tell that EO had a strange color.
00:44:50We knew that somehow sulfur had been removed from its surface and ejected into a great doughnut of gas orbiting Jupiter.
00:44:57Then, Voyager 1 sailed close to EO.
00:45:04There were a few places on EO which looked like the mouths of volcanoes, but it was hard to be sure.
00:45:10Then, Linda Morabito, a member of the Voyager navigation team, used a computer to enhance a picture of the edge of EO in order to bring out the stars behind.
00:45:20Four days after the Voyager 1 encounter with Jupiter, I was looking at an optical navigation frame.
00:45:28Now, in enhancing this particular quadrant, became very evident to me was an anomalous crescent in the upper left-hand corner just off the limb of EO.
00:45:39What was it?
00:45:40The plume turned out to be exactly in the position of one of the suspected volcanoes.
00:45:45So, basically, we realized at that point that what we were observing was a volcanic plume and, in fact, a volcanic eruption.
00:45:55Voyager had discovered the first active volcano beyond the Earth.
00:46:02We then found that EO has many volcanoes.
00:46:05There are at least nine intermittently active plumes and hundreds, maybe thousands, of extinct ones.
00:46:11The plumes can eject sulfur and other atoms off EO altogether and account for the sulfur clouds surrounding Jupiter.
00:46:18Rivers of molten sulfur flow down the sides of the volcanic mountains and are the probable source of EO's distinctive colors.
00:46:27The volcanoes may be tapping some vast underground ocean of liquid sulfur beneath a surface that is only a few thousand years old.
00:46:36So far, in our voyages to the outer solar system, we humans have stayed home and sent our robots and computers to explore in our stead.
00:46:51Someday, perhaps, we'll go ourselves.
00:46:55But suppose, like those Dutch sea captains of the 17th century, the computers aboard Voyager could keep a ship's log.
00:47:03That log, a combination of the events of Voyagers 1 and 2, might read something like this.
00:47:10Day 1.
00:47:14After much concern about provisions and instruments, we successfully lift off from Cape Canaveral on our long journey to the planets and the stars.
00:47:25Day 13.
00:47:35We have taken the first photograph of the Earth and Moon as worlds together in space.
00:47:40A pretty pair.
00:47:46Day 170.
00:47:47A problem in the deployment of the boom that supports the science scan platform.
00:47:52If the problem is not solved, we will be unable to take most of our pictures.
00:48:01Day 207.
00:48:02Boom problem solved, but failure of main radio transmitter.
00:48:06If the backup transmitter also fails, no one on Earth will ever hear from us again.
00:48:13Day 215.
00:48:14We cross the orbit of Mars and enter the main asteroid belt.
00:48:18Day 570.
00:48:21We can now make out finer detail on Jupiter than the largest telescopes on Earth have ever obtained.
00:48:27Day 640.
00:48:32The cloud patterns are distinctive and gorgeous.
00:48:37No painter trapped on Earth ever imagined a world so strange and lovely.
00:48:43The white clouds are ammonia crystals, high and cold.
00:48:50We do not know the nature of the red-brown clouds.
00:48:53Maybe phosphorus or sulfur is a stain.
00:48:56Or perhaps complex organic molecules of the sort that led 4 billion years ago back on Earth to the origin of life.
00:49:02And what is the great red spot?
00:49:05It is an immense swirling column of gas reaching high above the adjacent clouds, so large that it could hold half a dozen Earths.
00:49:18Its motion hypnotizes us.
00:49:26Some think that the red spot is a great spinning storm a million years old.
00:49:35Day 650.
00:49:37Encounter.
00:49:38A day of wonders.
00:49:39The ship maneuvers so we can take pictures of the multi-ringed basin on Callisto.
00:49:53Images of the astonishing lined surface of Ganymede.
00:49:58A close passage by Europa.
00:50:07And a view of volcanic Io.
00:50:14We successfully negotiate the treacherous radiation belts and accomplish the ring plane crossing.
00:50:20Looking back we marvel at the rings and see the sun emerge from behind the giant planet.
00:50:35We are outward bound on our mission to explore the outer solar system.
00:50:4110,000 years from now Voyager will plunge onward to the stars.
00:50:46We have made the ships that sail the sea of space.
00:50:56We travel past Jupiter three-quarters of a billion kilometers from the sun.
00:51:01Saturn one and a half billion.
00:51:03Uranus three billion.
00:51:05And Neptune four and a half billion kilometers away.
00:51:08In our ship of the mind we retrace the itinerary of the two Voyager spacecraft.
00:51:18On their journeys to Saturn and beyond.
00:51:24Saturn was first glimpsed through the telescope by Galileo.
00:51:28Its rings first understood by Huygens.
00:51:31But only now do we begin to penetrate its deeper mysteries.
00:51:38Saturn is the second largest planet in the solar system.
00:51:45Like Jupiter it is cloud covered and rotates once every ten hours.
00:51:50It has a weaker magnetic field, a weaker radiation belt.
00:51:54And a grand, magnificent, exquisite system of rings.
00:51:59The rings are composed of billions of tiny moons.
00:52:05Each circling Saturn in its own orbit.
00:52:08The biggest gap in the rings is called the Cassini division.
00:52:12After the colleague of Huygens who first discovered it.
00:52:16There are many other gaps.
00:52:18Each produced by the periodic gravitational tugs of one of the larger outer moons.
00:52:23From just beneath the ring plane we see a sky full of moons.
00:52:45Within the rings the individual moons become visible.
00:53:10They are orbiting chunks of snow and ice.
00:53:17Each perhaps a meter across.
00:53:19In young parts of the ring system there has not been enough time for collisions to round the edges of these fragments.
00:53:33The snowballs of Saturn.
00:53:36The snowballs of Saturn.
00:54:09Far from the rings, bathed in its red light, we encounter Saturn's immense cloud-covered
00:54:32moon, Titan.
00:54:39It has an atmosphere denser than that of Mars and a thick layer of red clouds which are
00:54:53probably composed of complex organic molecules produced by solar ultraviolet light and other
00:54:59energy sources from the methane-rich air.
00:55:09No ship from Earth has ever penetrated those clouds and viewed close up the surface of this
00:55:16tantalizing world.
00:55:23It seems likely that the ground is covered, encrusted with organic molecules raining from
00:55:30the sky.
00:55:37There may be volcanoes and valleys of ice and just perhaps hiding in the warm places some
00:55:47very different kind of life.
00:55:58Near an ice cliff of Titan, through a rare break in the clouds of organic molecules, we can
00:56:04see looming and lovely the ringed planet Saturn.
00:56:10It is a view that will still be appreciated centuries from now by our descendants, who will know
00:56:15it well, as well as we have come to know Hudson's Bay and the Barents Sea, Indonesia and Australia
00:56:25and New York.
00:56:28They will look back to the time when Titan was first glimpsed by the Voyager's spaceships
00:56:33on their epic journeys past the giant planets, out of the solar system, to the great dark
00:56:40between the stars.
00:56:58Since Cosmos was first shown, Voyager spacecraft have explored the systems of the planets Saturn,
00:57:06Uranus and Neptune, and have now passed the outermost planets on their way to the stars.
00:57:14We inserted the flavor of those encounters in our captain's log, but with image processing,
00:57:21we've been able to reconstruct astonishing movies of some of these worlds.
00:57:27Here for example is Jupiter with its great red spot, and volcanic Eos spinning before us,
00:57:36icy Enceladus, a tiny moon of Saturn on much of which, somehow, the craters have melted,
00:57:45and Miranda of Uranus, austere blue Neptune.
00:57:54Or consider Titan, the giant moon of Saturn.
00:57:57We've taken the nitrogen and methane in its atmosphere, irradiated it in the lab with electrons
00:58:03of the sort that have beamed a Titan from Saturn's magnetic field, and we make this stuff, which matches
00:58:11almost perfectly the observed properties of the Titan haze.
00:58:15What is it?
00:58:16It's a mixture of complex organic molecules.
00:58:19You drop some of the stuff into water, and among other things, you make amino acids, the
00:58:24building blocks of proteins.
00:58:25So, the starting materials of life are raining from the skies of Titan like manna from heaven.
00:58:32I can't wait until the Cassini mission sends an entry probe through the organic haze of Titan to its enigmatic surface.
00:58:41The Voyager spacecraft rush on past the planets and to the stars, still returning data.
00:58:51As it left the planetary part of the solar system, Voyager 1 turned back to take one last portrait of the planets of the solar system.
00:59:01And one of those pictures was of the Earth.
00:59:04A tiny blue dot set in a sunbeam.
00:59:09Here it is.
00:59:10That's where we live.
00:59:11That's home.
00:59:13We humans are one species, and this is our world.
00:59:17It is our responsibility to cherish it.
00:59:20Of all the worlds in our solar system, the only one, so far as we know, graced by life.
00:59:31So we continue to like the lights with the moon tree.
00:59:50Doesn't there think these instruments come in?
00:59:52You change himself, but you're still trying to Jeanne.
Be the first to comment