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00:00we're a long way from home and from our time this was our Milky Way when the galaxy was young and
00:13more fertile than it is today back then she birthed 30 times as many stars as she does now a firestorm
00:21of star creation it's a summer night 11 billion years ago we're on the planet of another star
00:28one with an ideal view of the Milky Way galaxy's chaotic stellar nursery our own star was a child
00:38of the galaxy's later years and that may be one of the reasons we exist after the short-lived more
00:45massive stars died out there was time another five billion years for those dead stars to bequeath
00:52their heavier elements to us these elements enriched and nurtured the formation of the planets and moons
01:00of our solar system and we ourselves are made of that star stuff those blazing pink clouds of hydrogen
01:09gas with a swaddling of countless newborn stars see those bright blue splashes their clusters of slightly
01:18older sibling stars gravity's embrace will transform this amorphous collection of gas and dust into the galaxy we call home today
01:48our sun is born
01:52the star endows her surrounding worlds with precious minerals diamonds and green olivine a mineral that
02:02will play a major role in our story the stars make planets moons and comets there's Jupiter the first
02:13born world of our solar system these future planets and moons are awash with organic molecules the chemical
02:27building blocks of life this is their inheritance from the deaths of other stars
02:33does the cosmos give rise to life as naturally as it makes stars and worlds this is our voyage to the heart of that mystery
03:03so
03:22so
03:27so
03:33I don't know.
04:03Long, long ago, when our world was young, there was a city at the bottom of a sea that covered the earth.
04:16It took tens of thousands of years to build this city, but there was no life on this world back then.
04:34So who built these submarine skyscrapers?
04:42Nature did.
04:44She made them with carbon dioxide and the same minerals she uses to make seashells and pearls, calcium carbonate.
04:52But these soaring towers were nothing compared to what happened beneath them.
04:58We'll need to get a thousand times smaller to see it.
05:01It doesn't look like much, does it?
05:19But just wait.
05:22Our restless Mother Earth cracked open and cold seawater poured down into her hot rocky mantle,
05:29getting richer in organic molecules and minerals, including a green jewel called olivine.
05:35This mix of water and minerals got so hot that it shot out of her with great force.
05:44The mixture became trapped in the pores of the carbonate rocks that would later become her towers.
05:49These pores were incubators, safe places where the organic molecules could become more concentrated.
05:59This is how we think that the rocks built life's first home.
06:04It was the beginning, at least in our little part of the cosmos,
06:07of an enduring collaboration between the minerals of Earth, the rocks, and life.
06:13See those snaky cracks?
06:18That's how this process got its name.
06:21Serpentinization.
06:22It's the evidence for the conversion of water and carbon dioxide into hydrogen and methane,
06:29the organic molecules that fuel this earth-shaking event.
06:33Those scientists who search for life on other worlds,
06:36they used to say, follow the water, because water is the most basic requirement for life.
06:41Now, they also say, follow the rocks,
06:45because serpentinization is so closely associated with the processes that make life possible.
06:59To witness the main event, we have to get even smaller.
07:03At this scale, these caves look vast,
07:09but they're actually the tiny pores in the mortar of the towers.
07:13These jewels are the organic molecules,
07:16which are, like everything including you and me, made of atoms.
07:20In order to turn these inanimate jewels into jewelry,
07:26the stuff of life takes energy.
07:30We think it happened in a treasure cave like this one.
07:33The energy came from the reaction between the alkaline water trapped within the towers
07:38and the acidic water of the ocean.
07:41That ancient treasure chest filled with rings and bracelets and necklaces,
07:47longer and more complex molecules until the greatest treasure of all.
07:52Life.
07:54We think it was that chemical reaction that provided the energy that powered the first cell.
07:59That was the spark that electrified the building blocks of life into something alive.
08:06Over time, the towers decayed,
08:09making it possible for the fledgling life within them to escape and evolve.
08:14VIRGINIA PLAYS
08:32What you've just seen is the most plausible scientific creation myth we have today for the origin of life.
08:52This hypothesis required the reunification of four long separated scientific fields, biology, chemistry, physics, and geology.
09:07We think life first took hold in the rocks and from day one life was an escape artist, always wanting to break free to conquer new worlds.
09:18Even the great big ocean couldn't contain it.
09:25If that's the true story of how life got started, it was long ago, back before the sky was blue, before the moon spun away from us to where it is today.
09:36Back when the planet was an ocean world with waters blood red with iron.
09:43Life would remake the world, the sea, and the sky.
09:48But life doesn't always act in its own best interest.
09:51There came a day of reckoning when life nearly destroyed itself.
09:57The cosmic calendar is a way for us to wrap our heads around the vastness of time.
10:06To grasp the history of the cosmos from the birth of our universe to this very moment, we've compressed all of it into a single calendar year.
10:15On this scale, every month represents about a billion years.
10:20Every day represents nearly 40 million years.
10:24That first day of the cosmic year began with the Big Bang, almost 14 billion years ago.
10:34Nothing really happened in our neck of the universe until about three billion years later.
10:43March 15th of the cosmic year.
10:47When our Milky Way galaxy began to form.
10:50Six billion years after that,
10:55Our star, the Sun, was born.
11:01It was August 31st on the cosmic calendar.
11:08Jupiter and the other planets, including our own, would soon follow.
11:12This was our planet nearly four billion years ago.
11:23September 21st on the cosmic calendar.
11:26When we believed life began.
11:29The atmosphere was a hydrocarbon smog.
11:32No oxygen to breathe.
11:35And no one to breathe it.
11:38We've only recently begun to appreciate how powerfully life has shaped the planet.
11:46When we think about the ways life has changed Earth,
11:49The first things that come to mind are the green expanses of forests and sprawling cities.
11:55But life began transforming the planet long before there were any such thing.
12:01A billion years after that tiny boomer, the bottom of the sea.
12:08Life had become a global phenomenon.
12:11Thanks to a champion that to this day has never been vanquished.
12:16I give you the cyanobacteria.
12:20In business for 2.7 billion years, cyanobacteria can make a living anywhere.
12:35Fresh water, salt water, hot springs, salt mines makes no difference.
12:41It's all home to them.
12:46Over the next 400 million years, the cyanobacteria, taking in carbon dioxide and giving back oxygen, turned the sky blue.
13:00But the cyanobacteria didn't just change the sky.
13:05They reached into the very rocks themselves and changed them too.
13:10Oxygen rusted the iron, working its magic on the minerals.
13:17Of the 5,000 kinds of minerals on Earth, 3500 of them arose as a result of the oxygen made by life.
13:28But here comes that day of reckoning.
13:47Cyanobacteria were the dominant life form on this planet, wreaking havoc wherever they went, changing the landscape, the water and the skies.
14:00This was 2.3 billion years ago, or late October on the cosmic calendar.
14:08But the cyanobacteria shared the planet with other beings.
14:13The anaerobes, life forms that had come of age before cyanobacteria had begun to pollute the Earth with oxygen.
14:21For the anaerobes, oxygen was poison.
14:24But the cyanobacteria wouldn't stop loading up the atmosphere with the stuff.
14:29For the anaerobes, and nearly all of the other life on Earth, it was an oxygen apocalypse.
14:36The lone survivors among the anaerobes were those who sought refuge at the bottom of the sea, deep in the sediment, where the oxygen could not reach them.
14:51The cyanobacteria acted like oxygen pumping machines.
14:56They continued in overdrive, and 400 million years later, they brought about an even more radical change to the planet.
15:04Remember those serpentinized rocks at the bottom of the sea that were cranking out hydrogen and methane?
15:11Methane is a powerful greenhouse gas.
15:14And back then, it was the main thing keeping the planet warm.
15:18But once again, the oxygen produced by life shook things up.
15:23It gobbled up the methane, producing carbon dioxide, a much less potent greenhouse gas, meaning it was not as efficient at trapping heat in Earth's atmosphere.
15:34Earth's temperature began to plunge.
15:38Life, the escape artist, busted out of the icy death grip that entombed the planet.
15:50The corpses of dead bacteria left behind a planet-wide reservoir of carbon dioxide.
15:57Volcanoes pumped the carbon dioxide in huge quantities into the atmosphere, warming the planet and melting the ice.
16:05Over the next billion years, life in the rocks continued their elaborate dance, taking the planet through freezes and thaws.
16:13Then, 540 million years ago, something wondrous happened.
16:22Life, which had been all about microbes and simple multicellular creatures, suddenly took off in what's called the Cambrian Explosion.
16:32Life grew legs, eyes, gills, teeth, and rapidly began to evolve the forms of its stunning diversity.
16:43We don't yet know what it was that allowed life to diversify so dramatically.
16:49But we have some plausible theories.
16:51It could have been all those calcium minerals in the seawater that came from the volcanoes.
16:56Life had grown a backbone and put on a shell.
16:59It had found a way to collaborate with the rocks to make its own armor.
17:05Now, life could grow larger and venture forth into new territories.
17:12Or maybe it was the protection afforded by the canopy built by the cyanobacteria.
17:18The oxygenation of the atmosphere created the ozone layer.
17:23This made it possible for life to break out of the safety of the oceans and inhabit the land without being assaulted by the sun's deadly ultraviolet rays.
17:35For billions of years, all life could do was ooze.
17:40Now, life began to swim, run, jump, and fly.
17:48Life, the escape artist, had gotten so good at wriggling out of every confine, no prison on earth could hold it.
17:58And there will come a day when life would even escape from earth.
18:04Life will not be contained.
18:08Retracing life's odyssey back to the very beginning required a new kind of science.
18:32One that reunited the disciplines.
18:34The man who founded this new approach also happened to be an escape artist himself.
18:39He fled history's most implacable killers right here in this forest.
18:45Jesting at his tormentors every step of the way.
18:49Remember this place?
18:59It's London's royal institution, where Michael Faraday spent his life.
19:04Back in his time, in the first half of the 19th century, the intimate relationship between life and the rocks had yet to be discovered.
19:14Before science could tackle the origin of life, it had to change.
19:19This development was foretold by a scientist whose gifts to the world were decidedly mixed.
19:26Christian Friedrich Schoenbein was a German-Swiss chemist who was conducting an experiment on using electricity to reduce water into its two chemical constituents, oxygen and hydrogen.
19:39Christian Friedrich Schoenbein thought he smelled something familiar, something like the air after a thunderstorm.
19:46Christian Friedrich Schoenbein had discovered ozone.
19:49Remember, that's the layer in the atmosphere that made it possible for our distant ancestors to leave the water for the land.
19:56And it still protects us from ultraviolet rays to this day.
20:00Christian Friedrich Schoenbein loved to experiment.
20:04So much so that his wife famously exacted a promise from him not to use their kitchen as his laboratory.
20:11Christian Friedrich Schoenbein had just invented a new weapon of mass destruction.
20:16Christian Friedrich Schoenbein had just invented a new weapon of mass destruction.
20:41A chemical explosive more powerful than gunpowder.
20:51Upon further refinement, gun cotton would industrialize warfare on a horrendous scale.
20:58But it was also Schoenbein who had a prophetic vision of a new field of science.
21:04He wrote in 1838, before the mystery of the genesis of our planets and their inorganic matter can be revealed,
21:11a comparative science of geochemistry must be launched.
21:17Fifty years later, the man who had realized Schoenbein's dream was born.
21:23He was another German Swiss.
21:25Victor Goldschmidt was so brilliant, he was offered a position here at the University of Oslo without ever taking a test or earning a degree.
21:36That was in 1909, when he was only 21.
21:40Three years later, he was awarded Norway's greatest scientific prize.
21:46Victor Goldschmidt saw the Earth as a single system.
21:52He knew that in order to get the whole picture, you couldn't just know physics, chemistry or geology.
21:59You had to know them all.
22:01This was in the early days of the study of the basic elements.
22:06Goldschmidt applied this new knowledge to create his own version of the periodic table.
22:11One that is still in use today.
22:14It illuminated how crystals and complex minerals could be formed from more basic elements.
22:19Goldschmidt was discovering how matter evolves into mountains, cliffs, canyons.
22:30In 1928, he made a fateful decision to accept an appointment at the University of Göttingen in Germany,
22:37where an institute had been built just for him.
22:40His colleagues thought these were his happiest years.
22:44Until...
22:501933.
22:56When Adolf Hitler came to power.
22:59Goldschmidt was Jewish, but not observant.
23:02Hitler changed all that for him.
23:04He now began to publicly identify himself with the local Jewish community.
23:09Hitler made it compulsory for everyone to list any Jewish forebearers going back several generations.
23:15There were those who tried to conceal a grandfather who might land them in a concentration camp.
23:21But Goldschmidt proudly declared on his forums that all of his ancestors were Jewish.
23:27Hitler and Hermann Göring, founder of the Gestapo, were not amused.
23:32They personally sent a letter to Goldschmidt telling him he was summarily dismissed from his university position.
23:42He fled to Norway with only the clothes on his back.
23:51Goldschmidt concentrated his research on olivine, that green jewel of a mineral left over from the formation of the solar system.
23:52He was fascinated by its power to withstand even the highest temperatures.
23:53He was the first to speculate that olivine may have played a role in setting the stage for the origin of life.
24:02At the same time, he wondered about the presence of olivine throughout the cosmos.
24:09This was the beginning of a field called cosmochemistry.
24:14In 1940, when the Germans invaded Norway, Goldschmidt took to carrying a cyanide capsule in his pocket,
24:21so that he could kill himself instantly if the Gestapo came for him.
24:26When a fellow scientist asked if he could get one of his hands,
24:29Goldschmidt took to carrying a cyanide capsule in his pocket so that he could kill himself instantly if the Gestapo came for him.
24:35When a fellow scientist asked if he could get one too, Goldschmidt answered,
24:46This poison is for chemistry professors only.
24:50You, as a physicist, will have to use a rope.
24:54But when the Germans arrived, Goldschmidt kept the cyanide in his pocket.
25:14He was sent to the Berg concentration camp before they were ready to deport him to Auschwitz,
25:19a place, he told friends, that had not been highly recommended.
25:29Goldschmidt was too important a scientist for the Nazis to exterminate.
25:34He was given the chance of survival if he would put his science in the service of the Reich.
25:40But Goldschmidt dared to toy with his captors.
25:44He would lead the Germans on a scientific wild goose chase.
25:48He sent them searching for non-existent minerals and deceived them into believing these were resources that would be critical to the war effort.
25:57His ruse could have been discovered at any moment.
26:01And that would have meant certain death in the most fiendish way possible.
26:05By the end of 1942, the Norwegian resistance knew that Goldschmidt was in the gravest danger.
26:13They arranged for him to escape across the Swedish frontier.
26:26Goldschmidt spent the rest of the war in Sweden and then England, contributing his knowledge to the Allies.
26:32Always in frail health, he never recovered from the hardships of the war.
26:37Victor Goldschmidt died a year and a half after it was over.
26:42But during that period, he wrote a research paper on the complex organic molecules that he thought might have led to the origin of life on Earth.
26:51And the ideas in that paper remain central in our effort to understand how life came to be.
27:02Goldschmidt never knew that the generations of geochemists who came after him would consider him their founder.
27:10Among his last wishes was a simple request.
27:17He wanted to be cremated and to have his ashes encased in an urn.
27:22Made of the thing he believed to be the stuff of life.
27:27His beloved, Olivine.
27:30The universe makes galaxies.
27:34Galaxies make stars.
27:37Stars make worlds.
27:40Are there other lost cities of life in the cosmos?
27:45Come with me.
27:46There are dues to be paid for cosmic citizenship.
27:58As a spacefaring species, you have to worry about contaminating the worlds you visit.
28:04And about bringing back alien stowaways that might pose a danger to your home world.
28:10There are protocols for planetary protection.
28:12NASA designates five categories of worlds in the cosmos.
28:19Earth's moon, for instance, is a category one world.
28:23A place so lifeless, we pose no threat to it.
28:27And it poses no threat to us.
28:31The riskiest mission of all is to a restricted category five world.
28:37Like this one.
28:38Mars.
28:39The conditions for indigenous life, in the past or even now, hidden in some subsurface recess, are not beyond possible.
28:48We have to be very careful for our own sake and for the life that could conceivably be there.
28:56The restricted cat five designation is a recognition of life's genius for escape.
29:01It applies to sample return missions from those worlds where life may have gotten started.
29:08Those worlds that may have or once may have had lost cities of life lying at the bottom of their seas.
29:15But in a sense, our robot emissaries themselves, our landers, rovers and orbiters, are a manifestation of life's relentless imperative to seek out and take new territory.
29:27And this means that some of our emissaries have to be destroyed as soon as their missions are over.
29:35Like, poor Juno.
29:36After a multi-year reconnaissance of Jupiter, NASA is sending her to her death.
29:43Not because they were worried about Jupiter.
29:45There's hardly any chance that one of our spacecraft could compromise future investigations of the giant gas planet.
29:52Any rogue microbe would catch a downtrap and sink where it would be broiled by the scathing temperatures.
29:59That's why Jupiter is only a category two world.
30:03But one of Jupiter's moons is a restricted cat five.
30:07And NASA can't take the chance that Juno might inadvertently crash into it.
30:12Europa is another one of only three restricted cat five worlds in the solar system.
30:17And one of Jupiter's 80, and still counting, moons.
30:34Michael Faraday discovered Earth's magnetic field.
30:37And there's one around Jupiter, too.
30:39We can see it if we switch from looking at Jupiter in visible light to looking at it in radio waves.
30:44Jupiter's magnetic field is much stronger and 18,000 times bigger.
30:51It's a gigantic trap for charged particles that are the solar wind.
30:55That's one of the things that lights up the aurora, the northern and southern lights on Jupiter.
31:01And it does the same thing on Earth.
31:03Imagine what it's like for little Europa and her sister moons to live so close to the king of the planets.
31:16Massive Jupiter holds Europa to him in a gravitational embrace so powerful that in four billion years she has never been able to turn her face away from his.
31:26Jupiter's hold on her is so fierce that it tears her skin apart.
31:32See those broad scars? Watch them closely and listen.
31:37That's the sound of a world being gravitationally tormented.
31:43It's called tidal flexing.
31:47And it's not just Jupiter.
31:49Her sister moons pull on her, too.
31:52We are half a billion miles from the sun's warmth.
31:56Five times farther away than Earth is.
31:59But this tidal flexing keeps Europa toasty inside.
32:03Beneath her chaotic surface there's an ocean ten times deeper than the deepest seas on Earth.
32:09We're on our way to another restricted Cat 5 world.
32:33No, not Saturn. Saturn's another Cat 2.
32:36Any life passing through those cloud belts wouldn't have a chance.
32:42They're made mostly of ammonia.
32:45Below them are bands of water vapor.
32:48In one of our future voyages we'll go there.
32:51At a terrible cost.
32:53It's not Titan either.
32:56Titan's another Category 2 world.
32:58Just as with Saturn, the possibility of us interfering with the life that might be there is too remote.
33:05Of course, there's always the chance that Titan life is stranger than our ability to imagine.
33:10Even if that's the case, there's little likelihood that any form of Earth life could harm it.
33:15There she is.
33:16Our restricted Cat 5 world.
33:21There's a world in our solar system that may harbor life.
33:24You're looking at two of the first people ever to see it.
33:25William Herschel saw farther into the deep waters of the cosmic ocean than anyone before him.
33:34His son, John, would also become a distinguished astronomer.
33:35But tonight is back when John was a child in the summer of 1802.
33:39That's when we first met them on an earlier voyage.
33:40John, I want to show you something.
33:41Come with me.
33:42John, I want to show you something.
33:43Come with me.
33:44Theirrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr N "...
34:04John, I want to show you something.
34:08Come with me."
34:13this was then the largest telescope on earth and would be for 50 years what
34:23have we here hmm isn't it awfully late for a little boy to be up father's
34:29supposed to show me something aunt Caroline William's sister Caroline
34:34Herschel was a world-renowned astronomer in her own right she was the first
34:39woman anywhere on earth to be paid for being a scientist she was just four foot
34:47three when Caroline was ten years old she was stricken with typhus she lost part of
34:52the vision in her left eye and stopped growing and yet she defied the
34:57limitations of her time to a point Caroline had just published her work in
35:04the catalog of nebulae and clusters of stars but it was under her brother
35:09Williams name it was 1802 after all her nephew John would grow up to build on her
35:17work and create the new general catalog many astronomical bodies are still
35:24designated by their NGC number today a few more degrees east and a degree north
35:38there she is father I've never seen that before it's snow star no son it's a new moon I call it
36:00Saturn too oh but father we must think of a better name than that that's your job my boy and John would
36:09do exactly as his father asked he named the moon Enceladus after the giant in Greek mythology who
36:17was the son of the earth and the sky Enceladus fought the goddess Athena in an epic struggle for
36:23control of the universe you don't have to be an astrobiologist to know at first glance that life is
36:39everywhere on earth it's changed virtually every square inch of the place from an alien point of
36:47view earth would certainly have a restricted cat 5 status but Enceladus keeps his secrets hidden deep inside
37:17those geysers of ice and water vapor are shooting out of Enceladus at 800 miles per hour they're this
37:30moon's contribution to the outermost so-called e-ring of Saturn but there's a lot more in them nitrogen
37:37ammonia methane and where there's methane it may be all of me Enceladus has been at this for at least
37:47a hundred million years it could keep cracking out water for another 9 billion years where's all
37:55that water coming from
37:56the blue snowflakes plummeted more than a thousand miles per hour we've come here to the southern
38:22hemisphere because that's where the ice crust is thinnest it's only a couple of miles thick
38:28that's why it's the best possible place to gain access to the underground ocean
38:36okay now's the time for a warning what you see here is entirely based on evidence that global ocean
38:49crazy curtain of geysers that weird snow at the surface it's all real we have multiple observations
38:57from the Cassini mission telling us that this is what awaits us on Enceladus
39:02but we're about to enter the realm of informed speculation this is what the leading space
39:09scientists think we might find when we send a spacecraft to dive straight into the heart of Enceladus
39:15when water up here is exposed to the vacuum of space it turns to snow
39:38and that scum is the stuff of life organic molecules it makes you wonder what could be waiting for us down
39:58below and that's a long way from here because we're in an ocean that's about 10 times deeper
40:05than the oceans of earth very promising that's carbon and hydrogen and the pH of the water
40:17is just like the early ocean on earth
40:19so
40:21so
40:23so
40:27so
40:29so
40:31so
40:33so
40:45so
40:47so
40:51so
40:55so
41:05why would this city of life be larger than the one at the bottom of the ocean on earth
41:09maybe it's because the gravity on Enceladus is so much weaker than it is on earth with less gravity
41:19with less gravity the towers are lighter and they can grow taller
41:27the currents are strong and they may have toppled some of the towers
41:31so
41:33so
41:43so
41:45so
41:47so
41:49so
41:51so
41:53so
41:55so
41:57so
41:59so
42:01so
42:03so
42:05so
42:07so
42:09so
42:11so
42:13you know
42:23you know it's a funny thing about us
42:25we think we're the story
42:27we're the end all and be all of the cosmos
42:31yet
42:32for all we know
42:33we're just the byproduct of geochemical forces
42:37ones that are unfolding
42:39throughout the universe
42:51galaxies make stars
42:53stars
42:55make worlds
43:01and for all we know
43:03planets and moons
43:05make life
43:07does that make life
43:09less wondrous
43:11or more