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00:00If I ask you what is a planet made of,
00:30then you'd probably say, well, rocks and iron.
00:38And for the planets of the inner solar system, like Earth,
00:41close to the heat of the sun, you'd be right.
00:48But if you head out into the frozen outer reaches of the solar system,
00:53then even the gases that make of our atmosphere,
00:56some nitrogen, carbon dioxide, and, of course, water,
01:00are all frozen solid.
01:04And the planets and moons out there, the mountains and glaciers
01:08and even the crust of the worlds themselves,
01:12are made of that solid, frozen, pristine ice.
01:18Ice that, in the extreme conditions we find beyond Earth,
01:24behaves in ways we never imagined possible.
01:34As we've explored the solar system,
01:36our spacecraft have encountered moons torn apart
01:42by great canyons of shifting ice.
01:49Dwarf planets where mountains of solid ice float across the surface.
01:54worlds where ice appears to cover one face,
02:03but leaves the other entirely alone.
02:11And elsewhere, alien aurora hang above the clouds,
02:15all thanks to a strange, newly discovered form of ice.
02:19Even here, on Earth, the behaviour of something as simple as ice
02:31has had, we think, profound consequences.
02:35Because without ice's counterintuitive behaviour,
02:39life on our planet may not have survived.
02:41Earth may not have survived.
03:12We begin our journey to the ice worlds,
03:15at the freezing edge of the solar system.
03:35Out here, the sun is so far away,
03:38it resembles just another star.
03:47Pluto is so remote,
03:49that it was only in July 2015,
03:52that we had our first, and to date only, close encounter.
04:01As it flew by,
04:03the New Horizons spacecraft sent back the first close-up images
04:06of this mysterious frozen world.
04:18It discovered a great heart-shaped plane,
04:21a thousand kilometres across,
04:23that dominates one face.
04:24around the edge of this plane,
04:39mountains made of solid ice,
04:41tower over Pluto's surface.
04:42And amongst its rugged uplands,
04:55ice was detected in a form no one ever expected to see on Pluto.
04:59Glaciers.
05:05Flowing rivers of ice on a world so far away,
05:12we expected nothing would be moving.
05:17That's because the temperature here is only 40 degrees Celsius or so,
05:21away from absolute zero.
05:26A temperature at which nothing should move.
05:33And yet New Horizons discovered regions of Pluto
05:36that for all the world,
05:38look like the frozen reaches of our planet.
05:40So, when you fly here over the years, how much does it change?
05:55So when you fly here over the years, how much does it change?
06:09It changes every day.
06:10Yeah?
06:10Yeah.
06:13The shape of the glaciers change.
06:16It's never the same.
06:21I'm just imagining flying over Flito, actually.
06:25Because it looks remarkably similar.
06:28Really?
06:30What is the topography like?
06:33It's like this.
06:34Same topography, same mountain heights.
06:36That's incredible.
06:46The discovery of Pluto's dynamic icy landscapes came as a huge shock.
06:51It forced us to rethink our understanding of this so-called dwarf planet.
07:00We're coming in for landings, so I'll just be talking to the airplane and not you.
07:05I respect that choice.
07:07I've had a lot of landings, but none quite like this.
07:10In fact, none like this at all.
07:15We're here to the world's most beautiful runway.
07:24Welcome to the glacier, you guys.
07:26We're here.
07:26We're here.
07:30We're here.
07:31We're here.
07:33Wow.
07:41You know, when we arrived, they said, oh, it's zero degrees, and I thought, that's great.
07:46zero degrees it's warm Fahrenheit zero degrees Fahrenheit it's about minus 20 up here it's just
07:55and you've got a real sense actually coming in if it looks frigid and frozen you know unmoving
08:01unchanging but it's so dynamic you can feel it in the wind as you land and then you know you can
08:08see you can see the way that everything flows
08:16just look at that glacier you can almost feel or see it moving this looks like a slow motion river
08:28and indeed it is moving it does flow very very slowly and the reason this great mass can grind
08:38its way down the valley is because of the unique properties of the ice from which it's made
08:46that bright blue ice certainly looks solid immovable it is formed by pressure so these
08:57snowflakes are falling down onto the top of the glacier and over time they build up their weight
09:03presses down increases the pressure and you get that particular crystalline structure of ice which
09:10looks transparent and blue but actually at those pressures and temperatures it's not completely
09:16solid the crystals are sort of arranged in planes a little bit like a deck of cards and that means
09:22that gravity is acting trying to slide this whole thing down the valley those planes can slip and slide
09:30over each other and that allows the whole glacier to move you can also get liquid water between the
09:37rock and the ice and that sort of lubricates the glacier and that allows it to slip as well so although
09:42this looks fixed and immovable at the conditions we find on earth this can almost behave like a like a fluid
09:52sort of sliding very slowly and deforming down valley
09:57glaciers were the last things we expected to see on pluto it's so cold here that we'd expect the ice
10:14ice crystals to be too brittle to flow nothing should slip nothing should slide
10:29yet that's precisely what these glaciers are doing
10:32so if they can't be made of water ice what are they made of
10:42as new horizons flew past pluto its detectors picked up an important clue
10:59these are images of pluto's surface and the colors correspond to different molecules different
11:06substances that new horizons detected on the surface the purple is methane the yellow is nitrogen and the
11:14green is carbon monoxide all these gases are frozen solids now the glaciers on pluto are primarily made of
11:25of nitrogen solid nitrogen nitrogen the nitrogen is something that we're all familiar with it's this
11:31stuff our air is pretty much made of nitrogen so our familiar experience of it is just we can't see it
11:38maybe cool it down
11:43then we can get it pretty easily to turn into a liquid
11:48now we carried on cooling that down it would turn into a solid
11:51nitrogen freezes at minus 210 degrees c and pluto's surface temperature at around minus 230 degrees
12:01ensures that glaciers remain solid but crucially the nitrogen ice is just 20 degrees or so away from its melting point
12:12that's very similar to the situation here on this glacier the glacier is about well the air temperature stays about minus 10 minus 20 degrees celsius
12:24heat it up by about 20 degrees and it'll melt so the temperature difference between the solid nitrogen ice and the nitrogen gas
12:34and the solid water ice and the water is about the same that means that with just a small rise in
12:45temperature pluto's nitrogen ice should be able to move
12:54so the discovery of its glaciers tells us something remarkable about pluto
12:58this tiny world must have a little heat at its core a faint warming from radioactive decay
13:08just enough to gently melt the bottom of these rivers of ice sending them on their way down the valley
13:15i think for me there are two lessons from the exploration of pluto one is that geology finds a way
13:28even so far away from the sun where temperatures are only 40 degrees or so above absolute zero pretty
13:34much the coldest it can be there can still be active geology particularly where something is close
13:41to its freezing point in pluto's case nitrogen ice the second lesson i think is perhaps even more profound
13:49is that nature's imagination far exceeds our own nobody expected that they would see such a beautiful
13:58active world so far away from the sun on the far icy edge of the solar system
14:11the similarities between earth and pluto are striking but new horizons discovered a wonderful difference
14:26pluto's glaciers flow through mountains reminiscent of alaska's great ranges
14:34but unlike mount denali's granite spires
14:37pluto's mountains pluto's mountains are made from frozen water
14:46but you can't imagine something that big that high being made of water that's the thing that
14:51that's crazy all water no no rock pretty much yeah and this leads to a surreal twist
15:00water ice in the mountains is less dense than the nitrogen ice in the glaciers
15:08so in places we've seen mountains floating on the glaciers
15:13carried away like icebergs onto the vast ice plain below
15:18pluto a world sculpted pluto a world sculpted by ice
15:31pluto and heading back towards the sun's glow we enter the realm of the ice giants
15:45vast gaseous worlds where ice storms range
16:00and on the innermost of these planets we've discovered a phenomenon eerily reminiscent of home
16:12of the earth in the mountains of the earth
16:18just above uranus's ice clouds hang beautiful ethereal aurora
16:30found not at the poles of the planet as on earth but scattered across its face
16:35even around the equator
16:48so what's creating this beautiful rare display
16:54the basic physics of the aurora on uranus is the same as the physics of the aurora on earth
17:09the sun's constantly emitting a rain of high energy charged particles which is called the solar wind
17:16and when those charged particles reach the earth most of them are deflected around the earth harmlessly
17:22off into space by our magnetic field now the earth's magnetic field looks very much like the field around the bar
17:30magnet i'll show you that by sprinkling some iron filings around the bar magnet
17:43and the iron filings line up with the magnetic field lines when the solar wind hits this magnetic field
17:50most regions of the earth is deflected harmlessly off into space but at the poles those charged particles
17:57can become trapped and then they can be accelerated down into the upper atmosphere and hit molecules
18:03in the atmosphere oxygen and nitrogen and that can cause those molecules to emit light to glow
18:09and that's what you're lucky you see as the northern and southern lights
18:14so somewhere deep inside our planet lies the equivalent of that bar magnet
18:25and of course it does in the form of a hot molten iron core spinning away as the earth rotates
18:34creating electrical currents and the magnetic field that projects out into space
18:39but uranus is different the aurora are not found at the poles and we don't think it has a molten iron or
18:51metallic core to support those electrical currents and so the fact that uranus does have aurora and
18:59therefore some kind of magnetic field there's tremendous mystery
19:08but we do have theories that allow us to piece together what might be going on
19:13imagine diving beyond the clouds of uranus beyond the slushy ice layer that flows around the planet
19:29and keep going towards the core
19:33we enter a region where the pressure approaches several million times that of earth's atmosphere
19:40and where it's almost as hot as the sun's surface
19:48rather than molten rock or metal like we find inside our own planet
19:53we instead find yet more frozen water
19:59in a bizarre form of matter known as super ionic ice
20:08normal water ice has a crystal structure like this so the reds are oxygen atoms the whites are hydrogens
20:17and you can see that they're bonded together into this regular crystal lattice
20:23within the lattice nothing that could carry an electrical current can flow
20:28so a magnetic field can't be created
20:33this is the crystal structure of super ionic ice the oxygens are still there bonded together into a crystal
20:43but now there are hydrogen nuclei electrically charged protons that can move freely through the crystal lattice
20:52that means that this is an electrical conductor
20:59it's this movement of the protons that could be contributing to uranus's magnetic field
21:05if so then the super ionic ice is at least in part driving the planet's mysterious aurora
21:20now this story is still far from fully understood for a long time this strange form of ice was only a
21:28theory but then a team pointed one of the world's most powerful lasers and a droplet of water
21:35and recreated the conditions that are present deep down inside uranus and just for a moment
21:42caught a glimpse of super ionic ice
21:49uranus a world illuminated by ice
21:58on the journey between ice worlds we edge ever closer towards the sun
22:06for an encounter with one of the most thoroughly explored planetary systems of them all
22:19the sun
22:28saturn's rings are constructed of countless crystals ranging in size from just a few microns to vast boulders
22:36and all of them made almost entirely from frozen water
22:51the rings are joined in their orbits by at least 146 moons
22:56and out towards the edge of the system nasa's cassini probe made one of its most surprising discoveries
23:16the moon iapetus resembles a walnut with a mountain ridge around its middle
23:26but that's not its strangest feature
23:32back in the 17th century only about 60 years or so actually after the invention of the telescope
23:38giovanni cassini discovered iapetus but he immediately noticed something strange about
23:44the moon as he watched it orbit the planet because he could see the moon on one side of
23:49the planet but then on the other side he couldn't now being sensible as a scientist after all he said
23:56well it's not somehow disappearing there must be another explanation and he guessed that one side
24:03of the moon must be very bright and the other side must be very dark and 300 years later we sent a
24:10spacecraft to saturn bearing his name
24:15and we discovered that he was right
24:22cassini sent back proof that one side of aapetus is icy white whilst the other looks as if it's been
24:29painted black so what could be creating such a sharply defined monochromatic world
24:43tremendous mystery but a clue could be found in looking at the line between the two hemispheres
24:49because there are jet black regions on the surface there that are also some of the hottest places
24:55in the saturnian system hot is relative of course it's still minus 140 degrees celsius
25:05on the dark side of the moon that's about 20 degrees warmer than the moon's icy face
25:12and we think that this difference is just enough to move ice around the moon in a very particular way
25:32the sunlight falls on that dark surface as iapetus rather languidly rotates actually
25:38about once every 79 earth days and it heats it up the water molecules rise up drift over to the light
25:46side and then condense and fall onto the surface making it brighter and brighter and brighter it's not
25:54like what's happening here so out there in the pacific ocean the water is turning into water vapor
26:01drifting over the cold land and falling as snow making the whole surface bright
26:16on the dark side of iapetus ice is warmed and creates a thin atmosphere of water vapor
26:31and where this vapor meets the colder white side of the moon it freezes to the surface again resembling fresh snow
26:42maintaining the bright icy white of this hemisphere
26:48but a mystery remains because iapetus is an ice moon
26:53so what is the dark material covering its other face
27:06in 2009 the spitzer infrared space telescope discovered this this is another ring around saturn but
27:14it's enormous it's one of the largest structures in the solar system this is about 12 million kilometers
27:21in the solar system this is about 12 million kilometers in the solar system
27:28later observations from nasa's wise telescope
27:32suggest that the disk may extend a further 20 million kilometers out into space
27:40at this vast scale saturn and its more familiar icy rings are barely visible
27:51it might seem strange that no one had seen one of the largest structures in the solar
27:56system until 2009 the reason is that that ring is very dark and very diffuse if you're transported
28:04into the ring you can look around and you wouldn't know you were in it spitzer saw it because spitzer
28:11is an infrared telescope and so it detected not visible light but infrared light the glow
28:18that the heat emanating from the ring the giant outer ring is therefore very different to saturn's ice rings
28:28so what is it made of and where did it come from
28:31phoebe is another of saturn's outer moons and each time a passing asteroid gets too close
28:48the resulting impact throws dark material out into space
29:03over billions of years numerous impacts have resulted in the dust from phoebe spreading around saturn
29:11forming its vast dark ring
29:17iapetus passes through the ring as it orbits and so that dark material from the ring gets deposited
29:26on the surface of iapetus this is a really slow process material folds onto iapetus and increases the
29:35size of that dark layer by about four hundredths of a millimeter every million years it's not a bad
29:42analogy this actually some of those sort of dust particles in the ring are about this size the size of
29:48the pepper grain some are bigger a few centimeters across or something but it is pretty much stuff like this
29:55and yet a puzzle remains why half black and half white
30:07iapetus spins on its axis once every 79 days and orbits around saturn once every 79 days it's what's
30:16called spin orbit locked it's like our moon so it always leads with one hemisphere as it orbits around
30:23saturn and passes through the ring
30:30iapetus then is a fluke of nature that exists thanks to the interaction of two moons
30:37within a dark ring right at the edge of saturn's domain
30:44a world painted by ice
30:53as we return ever closer to the sun ice becomes increasingly rare
31:07jupiter has 95 known moons
31:21including three large ice worlds
31:24and one of these is a promising target in our search for life beyond earth
31:39in 2022 nasa's juno spacecraft flew by europa
31:58and photographed a world crisscrossed with mysterious red lines
32:02grand canyons
32:11some 100 meters deep and tens of kilometers wide
32:17in places coated in a red substance that may be a newly discovered compound of salt and water
32:24the canyons canyons on europa are quite unlike anything seen on earth
32:54or indeed anywhere in the entire solar system
33:00the markings are geometric they form lines that crisscross
33:05over the surface so what can be causing that
33:09problem europa's surface features are an active area of research
33:15taking nasa scientists to the frozen reaches of our own planet in search of answers
33:20this is an image of a region on europa's surface called phaedra linear
33:26and see this feature almost looks like the grand canyon on earth it's actually about
33:3250 kilometers across
33:34a clue to what this is can be seen that if you look at the top line
33:39and the bottom line and just in your mind's eye draw these together
33:44you'll see that they knit together perfectly so this looks like the crust has just spread
33:52now there's only one other place in the solar system where we see features like this
33:56and it's here on earth it's caused by plate tectonics
34:03on earth is the internal heat of the planet as it forces its way through the crust
34:08the crust which is the driving force of plate tectonics
34:17you know one expected to see behavior like this on a moon
34:21on europa it's not molten rock that's driving its plates apart
34:39density measurements of the moon suggests that beneath the thick icy crust
34:44lies a different liquid a global subsurface ocean of water
34:51up to 150 kilometers deep it may contain two or three times all the water in earth's oceans combined
35:02so how can all that liquid water exist just below the surface of this frigid ice moon
35:07the answer lies with two other moons of jupiter with io and ganymede so here's jupiter and then io
35:27goes around four times as europa goes around two times and ganymede par this out goes around once
35:42it's called an orbital resonance four orbits to two orbits to one orbit that means that these three
35:49moons line up periodically and give each other gravitational kick which means that the orbits
35:56don't stay as nice circles they're all ellipses and that means that tidal effects just like the tides
36:05here on earth stretch and squash the moons and heat them up now the effect is strongest for io because
36:12that's closest to the giant planet and so that turns io into essentially one giant volcano for europa
36:19further out that heat melts the ice but the energy that goes into europa from this eccentric elliptical
36:29orbit around jupiter and some trickles into the moon so it really isn't enough on its own to produce the
36:37very active geology that we see on the surface
36:40we estimate the surface ice on europa is somewhere between 10 and 25 kilometers thick
36:59so whilst the tidal forces are enough for the subsurface ocean to remain liquid
37:04they're not enough to split apart all this ice
37:09so to drive the high energy geological processes we see on the surface of europa
37:14then there must be some kind of energy storage in the moon itself
37:20so i've got two camping stoves here these two pans are filled with water and it's at the same temperature
37:26zero degrees the only difference is that this water has ice in it and this has no ice in it
37:33the only difference when we start the stoves
37:40this is a thermal camera here because you know
37:43i wouldn't travel without one so it will tell us the the temperature of the water is rising
37:49eight nine degrees already whereas this one is still zero degrees
37:56even though we're putting all the energy into it yeah look you see that so why
38:06well this is a model of ice you can see the water molecules here and here and here and they're bonded
38:13together by these longer bonds which are called hydrogen bonds they're the thing that hold the crystal
38:19lattice in place and they're pretty strong so to melt the ice you've got to break all these bonds
38:27you've got to put a lot of energy into it so all the energy from this camping stove at the moment
38:32is going into breaking bonds in the ice it's not going into making all the molecules move around faster
38:38which is what temperature is so this one's getting hotter and hotter and hotter nothing is happening to
38:44this one now these have been cooking away now and i'll show you i have confidence i have confidence
38:50in physics i believe in it i would not put my hand in there i can see it'd be a stupid idea but there
38:58there you go physics works it's actually freezing
39:02now reverse that idea reverse that argument what happens then when i freeze water when i turn it from
39:16a liquid to a solid i get all that energy back out again huge amounts of energy as the bonds form
39:27and this is what we think may be happening on europa
39:32the subsurface ocean is warmed by tidal forces from jupiter and its moons storing energy
39:54then thanks to its elliptical orbit as europa periodically cools the ice begins to freeze
40:02the ice
40:06releasing the stored energy
40:12the volume of the icy crust grows as it freezes
40:20increasing the pressure
40:29until the entire canyon is cleaved apart
40:43and briny water from the ocean below surges up through the cracks
40:47where bathed in jupiter's intense radiation
40:55it turns red
41:05you're actually very familiar with this process so if your pipes burst in your house
41:09because they freeze where does the energy come from to burst the pipes it comes from water freezing into ice
41:17you're open to the sea
41:24europa is far more dynamic than we'd imagined
41:34and it's this dynamism that makes it a tantalizing target
41:38in our search for life under the ice
41:47at its simplest life needs three things
41:52water energy and the right chemical ingredients
41:55and the right chemical ingredients
41:58europa has the first two in abundance
42:02but the chemistry for life is missing
42:07but fortunately europa is not alone
42:11orbiting close by io has the missing ingredients we believe necessary for life in abundance
42:28erupting into space in enormous quantities around jupiter
42:33here's where the story gets even more wonderful
42:42because the volcanoes of io are constantly producing chemicals materials that rain down onto the frozen
42:50surface of europa but if it wasn't for the geology then they'd be separated forever from the ocean below by
42:5710 or 20 kilometers of ice but that active geology creating the plate tectonic like behavior can bring
43:06those materials those chemicals into the ocean and then we have all the conditions we think are necessary for the origin of life
43:20so europa's dynamic surface may form part of an extraordinary ecosystem
43:26one that stretches from one moon to another
43:33and work is already underway to send robotic probes into that distant icy ocean
43:45it would be a profound discovery to find life on europa but it would also be profound if we didn't
43:52because everything we think we know about the origin of life all the ingredients
43:57that are necessary seem to be present on europa so if we go there and send a cryobot into the oceans
44:04of europa and find nothing at all then it may be far more likely that we are alone for millions or even
44:15billions of light years in every direction
44:29europa a world completely encased in ice couldn't exist much closer to the sun
44:35because just a little closer in lies the solar system's ice line
44:45cross it and temperatures become too warm for ice to stay frozen for long
44:50when comets fall inwards towards the sun some of the ice they carry is transformed into water vapor
45:05in the ocean forming tails that streak through space for hundreds of kilometers
45:18inside the ice line then ice is rare but there are places where it can hold on at the margins
45:33of the ice on the surface of mars is held at poles
45:47here nasa's mars reconnaissance orbiter has captured these extraordinary images
46:00of a strange phenomenon that takes place on the southern ice cap
46:08dark spider-like formations that we think are being formed as the seasons turn
46:14during the winter it gets so cold on mars that the carbon dioxide in its thin atmosphere freezes
46:29creating crystals of dry ice that fall as snow on the pole
46:39snowfall on mars is nothing like snowfall on earth
46:43every winter between three and four trillion tons of carbon dioxide freezes out onto the surface that's about
46:5215 percent of the entire martian atmosphere and then in the springtime everything changes
46:59as the sun returns in the spring the ground is warmed
47:10and the frozen carbon dioxide vaporizes in an instant
47:14from solid to gas geysers of gas that lift dark martian dust high into the air
47:21and it's this dust as it settles that's causing the fan-like spidery marks that we've seen from orbit
47:36from mars it's just a short hop to our own world
47:52and earth too has permanent ice caps at its poles
48:04but there the similarity ends
48:15If an alien astronomer got a powerful telescope and pointed it at our solar system, they would
48:31immediately see there's something interesting and very rare about the third planet from
48:36the Sun, about Earth. Because they'd see a place like this, a place with mountains covered
48:43in snow and flowing rivers and clouds and rain. It's a place where water exists in all three
48:50of its phases, both solid, liquid and gas, at the same time. And that's extremely unusual.
48:59Let me show you what I mean. So I'm going to draw what's called a phase diagram for water.
49:05It has pressure there and temperature along here. The Earth sits at one atmosphere pressure,
49:14that's atmospheric pressure, there. And it sits at around zero degrees Celsius, give or take.
49:24So the Earth exists somewhere in this region here. I'm going to draw a line. I'll tell you
49:30what it is after I've drawn it. So these two lines mark out the region of pressure and temperature,
49:38where water can be either a solid, a liquid or a gas or vapor. And the Earth is here, a little tiny range
49:49where you can have solid, liquid and vapor. Mars sits somewhere around here. So that means that on Mars,
50:01water can either be frozen as a solid or it can be a vapor. But it can never be a liquid because the
50:07atmospheric pressure is too low. Pluto sits around here, minus 230 degrees, where water can only be a
50:15solid, frozen hard as steel building the mountains of Pluto. On the other hand, Uranus sits somewhere
50:22over here at, what, millions of times atmospheric pressure and extremely high temperatures. And there,
50:29we get these strange structures of ice, the supra-ionic ice. So Earth sits in a very narrow range of
50:37temperature and pressure, where water can exist in all three phases. And that's what makes the Earth
50:43unique, certainly in our solar system, and perhaps for hundreds or even thousands of light years
50:50beyond. It's this that allows a complex ecosystem to exist on the surface of our planet.
50:56Earth's snow cupboard mountains, great oceans, rivers, and storm clouds
51:16can only exist together thanks to the rare and very narrow temperature and pressure range
51:22that our planet enjoys.
51:34And that's surely necessary for complex life to have emerged on just one of the solar system's ice worlds.
51:42But there is one more twist to our story of ice. A strange property of the everyday ice with which we are so familiar.
52:05Ice on Earth has the unusual property that it floats on its own liquid. It's due to that
52:11complicated crystal structure with all those hydrogen bonds. Now, there are times in Earth's history when
52:17the planet almost froze solid. But because ice floats, there was always a bit of liquid water at the base
52:24of the ocean, and life could cling on in that liquid.
52:33That means that there has been an unbroken chain of life for 3.8 billion years, culminating in us.
52:41So, next time you stick a few ice cubes in your drink, just pause for a second and give a thought to the wonder of ice.
53:11The three key ingredients that you need for life are, number one, liquid water, two, a source of energy, and three, various chemical elements that we associate with life.
53:27And we think that Europa has all of these ingredients.
53:45Juno has deepened our knowledge of Europa. But the mission is due to end in 2025.
53:52Juno has deepened our knowledge of life.
53:55While we are yet to find any evidence of life on Europa, it's clear that this icy moon is worth a closer look.
54:09Sam Howell is part of a NASA team scoping a hugely ambitious attempt to explore the moon
54:15and its subsurface oceans in search of that elusive proof.
54:22It's all a guess until you go swimming in it. But, um, we're building this picture up where
54:28we understand how salt water and rock interact on Earth and the chemistry that produces,
54:35which is likely important to the emergence of life.
54:38How are we going to prove that?
54:40Sam Howell We're launching the Europa Clipper mission. And that will, uh, in the early 2030s, arrive at Jupiter and orbit Jupiter, surveying the entirety of the world.
54:53Europa Clipper is the first dedicated mission to Europa. And in fact, it's the first dedicated mission to any icy moon.
54:59The Europa Clipper is set to launch from the Kennedy Space Center in October 2024.
55:09And we have a payload of 10 instruments that are going to work together to characterize Europa's icy surface,
55:16its ocean, what their compositions are, and to figure out if Europa has environments that could support life.
55:23Any time you're anywhere near Jupiter, it's really dangerous. These high energy particles that are zipping around
55:35can hit your spacecraft and damage it. And that's one of the big challenges facing Europa Clipper.
55:43And it's not just the spacecraft that must survive Jupiter's onslaught.
55:47We know that this intense radiation, that's bad for life as we know it, life as we are. But maybe life on Europa doesn't mind it too much.
55:56But what's more likely is that the thick layers of ice that are at Europa's surface shield life in the subsurface ocean.
56:05We think that the icy crust is 18 miles thick, but Europa Clipper will tell us more.
56:10I'm really excited about learning about Europa's plumes. I think they could be the key to sampling
56:21the subsurface ocean with figure out if there are traces or ideas of life in those plumes. And that's
56:27something we're going to be able to do with this amazing spacecraft.
56:29Clipper will only ever survey Europa from afar. But future missions are being developed that one day may
56:40land on the surface and explore beneath the ice. There is no ice on this planet that behaves like
56:48the surface of Europa. There, the ice is so thick and so hard that the upper few miles are like concrete or rock.
56:56What we really look at are ways to pack enough heat into a cylindrical probe so that it can melt all
57:07the way to that ocean, but also carry along the scientific payload with us that we want to use
57:11to explore. So is this recording video now? Yes, absolutely. So I don't know if you've ever seen
57:19yourself on camera before, but there you go. Hello. We're just going to deploy it there,
57:25right into the hole. And then there we go. We're down in the lake.
57:35We're looking around the interface of the ice and water just beneath us.
57:47Finding life on Europa would be extraordinarily profound, because it's almost guaranteed that
57:53that that would be a separate instance of an origin of life. So Europa could teach us a lot about how
58:00life begins across the universe.
58:10We'll be talking about how life begins.
58:22What would you look for?
58:22Having experiences that while life begins, and as we go through andол
58:30We have a pyro machine to get ready at sea time and wait until after you hang out.
58:34You