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0:11
the fate of the planets is intricately tied with that of the star that they orbit so for our own solar system the sun dictates Our Fate as our sun has changed so has the potential for life on our neighboring planets their history show shows that habitability is a delicate
0:35
[Music] balance that doesn't always [Music]
0:49
last there is only one planet that has retained its water and habitability and that's Earth what remarkable about Earth is the stability of those conditions that Earth has been able to maintain Oceanic conditions at its surface throughout its entire history through billions of years and that's what's facilitated the very rich biological evolution of Earth Earth is a very special place it's the only place in the universe where we know definitively that there is life for that
1:21
to happen you need not just liquid water appearing on a planet but liquid water staying on a planet and that's the magic of Earth thanks to the size and geology of our planet the atmosphere has remained stable enough for billions of years protecting the precious water that has enabled complex life to
1:50
evolve life has woven itself into the fabric of the planet
2:04
and to shape the continents and the
2:10
[Music] oceans so that now life itself maintains the very atmosphere that protects our fragile ecosystems
2:29
[Music]
2:43
but as the sun continues to grow [Music] hotter temperatures on Earth [Music] rise upsetting weather patterns
3:01
raising great storms across the planet and devastating
3:12
droughts as plants around the world die out oxygen levels plummet around a billion years from now the age of complex life on Earth will finally draw to a close Earth will ultimately be like uh Venus and Mars Just mostly CO2 there'll be no nothing else really in the atmosphere and it will remain in that state as a sort of hot oven Planet until ultimately the sun when it uh uses up its hydrogen and goes into a different phase will
3:47
become what we call a red giant you know as we've seen in other stars throughout our galaxy throughout the Universe our sun will continue to get hotter and hotter over time and in that point it will expand greatly to the point where it will uh nearly engulf the Earth entirely and at that point the uh planets will will lose their atmospheres and they'll just sort of swept
4:24
away as it exhausts its hydrogen fuel the sun's Outer Edge inflates as our star enters its red giant phase expanding millions of kilometers out into
4:44
space Mercury is the first to be
4:58
engulfed then Venus's fate is
5:12
sealed some models predict that Earth May barely escape the fiery fate of its
5:21
neighbors hanging on Beyond the Edge of the dying star with Mars
5:30
[Music]
5:38
but the long era of the four terrestrial planets will be
5:46
over the lives lived on one of them nothing more than a distant [Music]
5:58
memory poor Uranus it's got rather boring clouds truth be told so there wasn't a lot to see with the
6:14
cameras passing close to the planet Voyager sensors reveal why Uranus is so
6:25
featureless temperatures here are the coldest of any world in the solar [Music] system there's simply not enough heat to drive the storms seen on Jupiter and Saturn Uranus is an entirely new class of Planet an ice Giant [Music] and more surprises were to [Music] come Uranus has [Music]
7:23
rings we knew long ago from telescopic observations the Rings were there at Uranus we didn't didn't know their configuration uh or their shape Voyager begins to explore the ring system and spot something curious in the
7:46
shadows two moons Cordelia on the inner edge of the brightest ring and ailia on the Outer Edge helped to organize the system
8:09
particles within the Rings can be moved inwards or outwards as these tiny objects called Shepherd moons whose gravitational force can shape and sculpt the Rings themselves
8:33
but it's the orientation of the orbits of these moons and the Rings themselves that singles out Uranus as the strangest of
8:46
Worlds Uranus looks bizarre the Rings rather than looking like that when you look through a telescope they're actually orbiting up and over the top of Planet the whole thing is tipped like a spinning top this bizarre orientation hints at an unusual
9:19
past since the beginning everything in the solar system has been circling in the same direction it begins with a vast cloud of material that orbits the young
9:36
sun over time the material draws
9:43
together forming each of the
9:51
planets today they all orbit the Sun and spin on their axes in the same counterclockwise direction as that primordial
10:05
Cloud except for Venus and Uranus which spin in the opposite direction but Uranus is even stranger because the entire planet is on its side this was a really strange system so why is Uranus so tipped on its side if a roughly earth-sized object smashed into Uranus late in its formation history then that would have had the proper amount of momentum to basically knock it on the side
10:52
[Music]
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and the Collision may also help to explain another of Uranus's Mysteries why the planet is so cold that impact presumably relinquished all of that internal energy that the planet had when it first formed and has left it as a relatively dead and sluggish world
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[Music] much is learned during this Brief
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Encounter but Voyager strangest discoveries are yet to come [Music]
12:07
what powers weather is very different depending on where you find yourself in the solar system the Earth's atmosphere and the weather on Earth is is driven largely by one thing and that's the sun and the sun pours its energy down through the atmosphere and it hits the surface and the surface of the Earth then warms up with Earth you've got all the energy coming in from the Sun heating up the surface creating thermals that then uh then drive the atmospheric flows that we
12:36
see somewhere like Saturn doesn't have a surface to be heated up so when you compare the weather systems on these giant planets to those that we have on Earth you have to sort of tear up the rule book a little bit the sun is the great controller of Earth's atmosphere but in the outer reaches of the solar system where Saturn lives Sun light is 100 times weaker it means some other heat Source must be driving Saturn's incredible
13:17
weather as Cassini studied the cloud tops of Saturn it was able to infer a huge amount about the truly strange world that must lie beneath and the energy source that helps power this planet we had a whole variety of scientific goals at Saturn and one of the main ones was to understand the meteorology of the Saturn atmosphere and what energizes the winds that we see on it and so on and we have affirmed now the belief that atmospheric systems on
13:50
Saturn are actually powered by energy from below from an internal heat Source on Saturn they're not powered by sunlight we have on the
14:09
earth looking deep inside the planet reveals a heat Source shaped by extreme pressure within huge clouds of water Cassini records lightning 10,000 times more powerful than any on Earth
14:34
this lightning transforms methane gas into enormous clouds of
14:47
so at 8,000 km deep the pressure of the atmosphere is 80 times greater than that at the bottom of our deepest oceans enough to transform form this graphite rain into
15:11
diamonds but even these diamonds are likely destroyed by the pressures of [Music] Saturn eventually dissolving
15:35
30,000 km down and Saturn's heat source is revealed here pressures are so intense that the atmosphere behaves like a liquid metal able to conduct electricity in this state molon helium Falls like rain and as it merges with the surrounding material kinetic energy is released as incredible amounts of heat and it's this extraordinary heat source that helps Drive Saturn's [Music] weather sent to look for conditions where where life could have begun is NASA's Mars reconnaissance
16:40
[Music] Orbiter mro sends back more data than all other Mars missions combined
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[Music]
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has three cameras on board the first is the Marcy weather camera it sees Horizon to Horizon on every orbit so it builds up a map of the entire planet every day so you can see a global weather map every day on Mars the second camera is the context camera it provides high resolution and it's covered about 99% of the surface [Music] mro has made more than 60,000 [Music]
17:40
orbits its high resolution cameras revealing Mars in unprecedented detail discovering polar [Music] Avalanches shifting sand
17:57
dunes and what look look like seasonal flows of sand or even liquid
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meltwater then in 2017 mro turns its gaze to one of the red planet's oldest features the aidonia Basin thought to have been an ancient sea aridia Basin is a huge Basin in some of the most ancient crusts on Mars it formed about 3.8 billion years ago and it held more water than 10 times that of the great lakes or three times that of the Caspian Sea on
18:42
[Music] Earth and it is on the ancient seabed that mro sees something remarkable emeros saw a massive 400 met thick deposit formed from a mineral that formed forms in deep sea hydrothermal environments such as one that might have undersea
19:06
vents Mars not only had the same ingredients for life as Earth it also had an active environment to spark it into
19:23
action aridia Basin was an ancient sea 3.7 to 3.8 billion years ago and that's about the same time when life was first emerging on Earth this might have been a place where life could have existed because those hydrothermal vents underneath that sea might have created a very conducive environment for life these initial conditions in the history of both planets look so similar that it seems reasonable to expect that
19:53
this could eventually lead to life these actively fertile conditions are thought to survive in places like the aidonia Basin for hundreds of millions of [Music] years but then 3.7 billion years ago something happens that transforms prospects for Life on Mars forever
20:35
Mars underwent a fairly substantial transformation in its climate climate got colder what liquid water there was either soaked into the ground and froze or froze at the surface a lot of It ultimately would get transported to the poles where it forms these big thick ice caps that we see
20:56
today at the same time time as the temperature
21:03
plummets Mars becomes more volcanically
21:09
active leading to catastrophic
21:17
flooding water rages down from the Southern
21:23
Highlands until in a place known as easma it plunges over Cliffs 4 km [Music] High creating the largest waterfall the solar system has ever seen [Music]
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[Music]
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cascading into a spectacular Canyon 10 km wide by 100 km [Music]
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long once the floods subside the water disappears The only trace it ever existed etched into the planet's [Music] surface
22:39
Neptune an ice giant 17 times the mass of
22:49
Earth over 1 and A2 billion kilom farther from the Sun than Uranus Neptune is almost chemically identical
23:03
yet bizarrely it couldn't be more different Neptune in a way was almost a relief because it it wasn't featur L you know it's like oh good a planet with with clouds and features
23:22
again Neptune was a great excitement it's got swirling clouds really strong wind
23:32
wind at 1500 mph incredibly fast the fastest winds that we've got in the solar [Music]
23:45
system one of the things that Voyager discovered was an immense dark Vortex within the
23:56
atmosphere a huge swirling dark
24:07
spot we say it's a giant storm but just those words don't fully contain we're talking about a storm the size of a planet Earth or larger and the surprises keep [Music] coming even though it's much farther out Voyager discovers Neptune is warmer than [Music] Uranus and the source of the heat is another Oddity of this strange planet in fact when we look at this Dynamic activity in these extraordinarily cold regions we really
24:47
are at a loss to understand just what's going on here one theory is that the buildup of pressure beneath the thick layers of cloud
25:01
turns the carbon and the methane into a rain made of diamonds they then melt as they fall into the interior of the planet producing the extra
25:19
heat as the heat makes its way out into the Frozen coals of space it churns the entire atmosphere whipping up winds around the globe there are no mountain ranges no valleys no Continental boundaries to get in the way of the perfect fluid dynamical
25:43
flows what that means is that when you start a weather pattern going when you start a Vortex spinning or you start a plume Rising there's very little to get in the way of it so those winds that develop and go around they just keep going around around and around there's nothing to slow them down no friction with the
26:05
surface and the extreme cold here makes the atmosphere less
26:18
viscous creating supersonic winds that outpace anything seen on Jupiter or Saturn
26:43
most surprising is
26:50
Mercury the least explored of the rocky planets because of the difficulty of getting into orbit around a Planet so close to the Sun 5 4 3 main engine start 2 1 and zero and lift off of messenger on NASA's mission to
27:16
Mercury a planetary Enigma in our inner solar [Music] system now going through the sound barrier following a direct route to Mercury would be [Music] impractical a spacecraft would arrive at such high velocity it would need to haul a prohibitive amount of heavy fuel in order to slow down enough we uh just had spacecraft separation ground solid jettison so messenger controls its speed by stepping from one planet to the next using their gravity to slow
28:18
itself even so messenger still approaches Mercury moving so fast that it is forced to fly past the planet three times slowing on each
28:40
pass until after nearly 7 years of flawless navigation it arrives safely in
28:54
orbit at last able to begin its mission mapping Mercury's
29:04
surface that first image ever acquired from orbit around Mercury was amazing when it finally came in it looked perfect it looked exactly like we expected it to be for me that was the real moment when I realized that we had successfully made it into orbit and everything was working this pioneering Voyage has led to a completely new idea of how Mercury may have formed
29:37
Mercury is the most cratered planet in the solar
29:44
system with many puzzling features that hint at a violent
29:52
past mercury has a very unusual orbit if you were on the surf surface of the planet you would actually have to go around the Sun twice to get one full Mercury solar day also highly unusual is the planet's disproportionately large core Mercury is basically a big ball of metal surrounded like a tiny bit of rock how do you end up with a planet that has so much metal inside and then almost none on its surface that was a huge mystery and the major question is is why why is it like
30:30
this when the rest of the planets aren't a clue to understanding these strange features was found in Mercury's chemistry so very soon after we got into orbit we started to get chemical data back from the surface and we immediately uh got some surprises the tiny probe detects volatile chemical elements in concentrations that no one had thought possible this close to the
31:07
Sun these are elements that go into rocks but that evaporate at relatively low
31:17
temperatures and immediately told us that some of the older ideas of how Mercury formed could not be correct what messenger discovered about Mercury could suggest a new twist in the story of the solar
31:38
system just a few million years after its formation the young Mercury is seething with the heat of its violent birth
31:58
slowly a crust formed rich with volatile elements if it had been close to the Sun these elements would have evaporated before the rock hardened so what could explain why they're so abundant on Mercury today the orbits of the planets and their current locations have changed over the history of the solar system so where things are today doesn't mean that's necessarily where they formed they could have and probably did move from different locations to where they
32:33
are now one possible thing is that mercury didn't form where it is today it form much closer to the other planets maybe even outside of Venus or Earth or in somewhere in between there if Mercury had formed near Earth and remained at a more comfortable distance from the Sun its Destiny could have been very different [Music]
33:07
but it wasn't to be so what turned it into the strange sun-scorched world we see today we don't know the full story what we have right now are theories and as we have new observations we are trying to change everything to fit those observations [Music] Messengers evidence of the volatiles on Mercury surface and the unusual size of its core suggest an interesting new
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Theory it's possible Mercury began life as much as 160 million kilm further from the Sun than it is
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today in the region of space where the young Earth is also forming a region with scores of planetary embryos all fighting for
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position in the chaos it's possible that something large pushes Mercury off orbit and in towards the Sun [Music]
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[Music]
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Mercury brushes against another planetary
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embryo this glancing blow removing much of its crust and mentle
35:29
now little more than a metallic planetary
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core Mercury continues toward the
35:45
sun ending up in the peculiar elliptical orbit we see
35:53
today before we sent the messenger mission to Mercury I think we had a very simplistic idea of what it was going to be like and Mercury turns out to be a more complex place with a more interesting and complex history than we had previously imagined but of course all things have to come to an end and once we were out of fuel we could no longer burn our engines to keep from crashing into Mercury and sequencers
36:22
launch after 4 years of observations Messengers fuel finally runs
36:37
out and the spacecraft adds yet another crater to this tiny world where any prospects for life were scorched away when it was thrown too close to the Sun
37:00
the sun's outer Corona Burns at a scorching 1 million de releasing a barrage of charged particles that travel at around 400 km/
37:15
second the solar [Music]
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wind this Onslaught would strip away our atmosphere but for the power power ful force that protects us the Earth's magnetic
37:37
field solar wind is this stream of charged particles that come streaming out from the Sun and at Earth which has a powerful magnetic field when those charged particles begin to get close to Earth they get diverted around Earth by interactions with that magnetic field that protection keeps solar wind and other ionizing radiation off of the surface so on Earth where we have this really great magnetic field we are nice safe and sound inside the shell of that
38:09
protected from all that radiation the magnetic field of Earth effectively forms a protective bubble around the Earth's atmosphere and when the sun dips below the Horizon there are times when Earth's protective force field is visible [Music] the Aurora is a stunning display of Earth's magnetic field in [Music] action it's best seen at the poles but across earth it's protecting our atmosphere and all life on our planet this vital protective shield is generated deep within
38:59
the way a magnetic field is generated inside a planet is when you have convective Motion in a fluid that is capable of conducting electricity and in the earth that electrically conducting fluid is liquid iron and the molten portion of the earth's core is a place where these motions take place and it can set up a magnetic field [Music] just like Earth Mars once had a molten metallic core generating a magnetic field around the [Music]
39:42
planet aoras danced above Mars's poles protecting its atmosphere and seas below
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but the field didn't
40:02
last in the oldest rocks on Mars you see evidence of a once powerful magnetic field you get to the younger rocks rocks that are 3 billion 2 billion 1 billion years old no evidence of a magnetic field whatsoever and there is no intrinsic magnetic field on Mars
40:25
today half a bill million years after it Formed Mars's magnetic field dies out the bright auroras above its poles slowly fade
40:41
away as the shield that protects the planet shuts down for
40:49
good once it stops then what happens is all the atmospheric components things like hydrogen oxygen that make up water they get stripped away because you don't have the shield the magnetic Shield anymore so the high energy particles that come in from the Sun and from outer space they begin to strip away the components that make up water without its magnetic field to protect it Mars's atmosphere and then water slip away into space
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so why did Mars lose its protective shield what happened deep beneath its surface that stopped Mars from developing like
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Earth the answer lies at the beginning of Mars's story at its very creation
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4.6 billion years ago when the planets were forming from the dust cloud circling the sun early differences between Mars and Earth set the young planets on very different
42:24
paths Mars forms further from the Sun where crucially there is less Rocky material to build a
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planet Mars is different because it's not just further out it's actually much smaller if a planet gets to be too small it just freezes all the way through Mars is just half the diameter of Earth me meaning its core cooled more quickly and so it lost the heat that powered the Dynamo that generated its protective
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shield Mars's small size condemning the planet to die
43:34
millions of years ago Saturn has an extra
43:44
Moon perhaps 400 km across and formed almost entirely of
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ice but this Moon is doomed it's orbiting just too close to resist the immense forces of Saturn's [Applause] Gravity the Rings probably formed from an object that got too close to Saturn there's this invisible boundary around Saturn called the RO limit and that's the limit depending on what you're made of where Saturn's gravity is strong enough will actually pull you apart that the gravity on the side closer to Saturn is strong enough that compared to the gravity on the other side that will L
44:28
literally rip you apart you don't have enough gravity of your own to stay
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together a leading theory suggests that just beyond Saturn's atmosphere an ice Moon approaches close to or even just inside its Ro limit
45:00
as Saturn's immense gravitational force pulls it apart the moon begins to rupture
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catastrophically a world ripped apart by its proximity to a giant
46:07
up to 17,000 trillion tons of ice breaks apart in orbit around
46:21
Saturn and thanks to the speeds this material is traveling it's like likely that in just a few days it spreads out to encircle the great [Music] giant Saturn's iconic ring is now in [Music] place but as Cassini turns its instruments towards it it sees a single ring transformed
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the images we returned they were phenomenal they were resolution factor of maybe 20 times better than anything we had had [Music]
47:23
before Cassini reveals how Saturn's giant rings have
47:30
evolved this debris now forms a dis wider than Jupiter yet on average just 10 m thick within moon-sized chunks of ice orbit the structure clearing great voids turning one ring into
47:55
many but it's as Cassini captures images with the sun directly above the equator that the most surprising feature of the Rings emerges we knew this was going to be a time for us to investigate the third dimension something that you don't get to see when you just look at picture of Saturn's rings and what we found was staggering
48:30
just right out of the gate we saw vertical structures I just can't tell you how surprised we were to see this it's just the spectacle of it was just unanticipated I have just imagined flying along in a shuttlecraft across the ring right close to the ring so to my perspective it would be almost like it was an infinite sheet of gleaming debris and I'm flying along and flying along and flying along and suddenly I come upon a wall of rubble that's 2 miles
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High I mean is that cool or what really i' I've said over and over again they should put that in a movie this once Tiny World of rock and Ice that is has seen the most dramatic Transformations is today the Solar System's greatest
49:38
[Music] Jewel after more than a decade in orbit Cassini has forever deepened our understanding of Saturn but its mission is far from over
50:01
as the young Jupiter circles the sun it clears a path through the gas cloud that envelops the early solar system but that process causes it to do something
50:19
alarming Jupiter begins to spiral inwards
50:26
plowing straight through the region of space that would become the asteroid
50:36
belt when the young Jupiter moves through the primordial asteroid belt things get scattered around things get gravitationally deflected and as a consequence of all of this gravitational interaction more than 99% of the original mass that was there is basically now gone
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the asteroid belt has been disrupted over time by the movement of the giant planets and this has acted to throw material from the asteroid belt out of the asteroid belt into the outer solar system these protoplanetary cores like series were never able to graduate to full-fledged planets because there was just not enough material in the orbital neighborhood [Music] when Jupiter passed through the primordial asteroid belt it starved series of material halting its
51:39
growth and the dwarf planet was condemned to live out its life as a cold Barren Rock
51:56
but siries isn't the only World in our solar system whose development was cut short Mars would suffer a similar fate at the hands of
52:20
Jupiter after marauding through what would become the asteroid belt Jupiter enters the region of space where Mars is
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forming continuing its Journey spiraling towards the
52:50
Sun as Jupiter bulldozes inwards its immense gravity scatters material in all
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directions some is sent careering into the
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Sun and some is thrown out into Interstellar
53:37
space it is because of the gravitational clearing of this neighborhood by Jupiter that Mars was unable to grow to more than 10% of that of the Earth this is why Mars is small
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and by clearing material out of the inner solar system the giant planet may also have prevented the formation of the super Earths we see in other
54:11
systems and if it had continued moving inward our planet too might never have
54:22
formed but then just as it looks like Jupiter will sweep everything away the giant planet stops in its
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tracks because in the shadows of the outer solar system another planet is forming the solar system second gas giant
54:58
Saturn and its arrival changes everything as Jupiter moved inwards Saturn moved inwards and caught up to Jupiter's orbit when this happened the two locked into a special configuration known as a mean motion resonance this is where the planets begin to interact gravitationally in a very coherent Manner and now locked as a unit the two reversed their Mig migration course and moved back
55:32
out Saturn caused Jupiter to
55:40
[Music] retreat leaving behind just enough material from which the inner planets could
55:53
form Mercury
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Venus and our
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home Earth is in exactly the right location to provide the environment for life to develop so if Jupiter had moved around even more who knows maybe life never would have developed in the solar system As We Know
56:30
It And as its voyage across the solar system draws to a close Jupiter helps to provide our living world with its most precious [Music]
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ingredient today 2/3 of our planet surface is covered by ocean more than one 1.3 billion cubic km of [Music] water each drop teaming with
57:10
life one of the big questions about the evolution of our solar system is how did we get water here on this planet so we think that the inner planets didn't naturally form with a lot of water water is primarily in the outer solar system system but if you end up having Jupiter and Saturn moving outwards then that is able to suddenly deliver more water into the inner solar
57:40
system locked in a gravitational dance with Saturn Jupiter moves back through the asteroid belt and as it does so water Rich material is flung inward where it is incorporated into the growing terrestrial worlds so the movement of the giant planets have actually played an important role in the delivery of water to the inner solar system in a sense it is Jupiter's outwards motion through the asteroid belt that we have to thank for the
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delivery of water to the surface of the Earth the Earth would be quite a different planet if not for Jupiter's primordial dance
58:35
around 100 million years ago an asteroid 10 kilm across is ejected from the asteroid
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belt dislodged from its orbit by Jupiter it is now on a collision course with Earth [Music]
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[Music] when it strikes the impact generates a fireball so hot anything within a 1,000 km radius dies instantly
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the impact throws some 300 billion tons of sulfur up into the
59:43
atmosphere and during the nuclear winter that follows 75% of species plant and animal are wiped from the face of the Earth in including the largest creatures ever to walk on its
1:00:04
surface by driving the dinosaurs to Extinction Jupiter cleared the way for us to inherit the earth and although it still occasionally flings asteroids our way Jupiter also protects us
1:00:36
for objects heading toward Earth from the far reaches of the solar system the giant planet's immense gravity acts as a
1:00:50
shield around 100 years ago a lump of rock and ice for km across is hurdling towards the inner solar system but Jupiter stands in its way 5 4 3 2 1 we have ignition and liftoff of Atlanta and the Galileo spacecraft Bound for Jupiter 70 years later a mission launches that will witness just how effective a shield Jupiter can
1:01:31
be on board the space shuttle [Music] Atlantis the Galileo
1:01:46
[Music]
1:01:51
Orbiter 3 years after Galileo launches Comet Shoemaker le9 has been captured by Jupiter's
1:02:03
gravity and now locked in the giant planet's deadly Embrace tidal forces begin to tear the comet
1:02:15
apart its journey into the inner solar system cut short what happens next presents the Galileo scientists with a unique opportunity and so everyone was observing it and they realized two things one is that it had just passed very close to Jupiter and probably had gotten pulled apart by Jupiter's tides and the other was that it was going to crash into Jupiter two years later the discovery that a comet was about to hit Jupiter was a huge surprise and very exciting
1:03:01
after crossing the inner solar system Galileo is approaching the spot where it will witness the comet's final moments we knew Galo would be able to see the flashes directly we knew that the impacts were going to occur on the night side and that Galo was going to be able to see him
1:03:28
on July 16th Galileo sees the first fragments of the Comet enter Jupiter's southern
1:03:39
hemisphere at 60 kmet per second the fragments really heated The Atmosphere Red Hot almost to the temperatures of the sun and the pieces hit the planet one after the other pieces of comet Shoemaker Ley 9 strike Jupiter over the course of 6 days they look like big flashes on Jupiter the pictures of the impact were
1:04:16
fantastic these tiny Points of Light captured from 240 million km away are the only only time a comet strike has ever been
1:04:39
witnessed the most destructive impact releases energy equivalent to 6 million megatons of TNT leaving behind a giant Dark Cloud 12,000 km across
1:04:58
by capturing objects in its orbit and incinerating them on impact Jupiter protects us from bodies that might otherwise collide with Earth
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