Kind: captions
Language: en
[Music]
Arthur C Clark had a sequel to 2001 A
Space Odyssey it's called 2010 Odyssey 2
and at the end of it an alien
intelligence converts Jupiter into a
star as a group of astronauts narrowly
escape the implosion they receive the
following message from the aliens all
these worlds are yours except Europa
attempt no Landing there now that was
just a novel but it suggests that
already in 1982 we suspected that Europa
might offer our best chance of finding
alien life in our solar system 42 years
later in October 2024 NASA is actually
launching the most advanced mission to
hunt for signs of alien life and it's
going to Jupiter's moon
Europa there's just one
problem Jupiter kills everything around
it so how could life even exist
there and how do you make a probe that
can withstand the perilous
conditions deep inside Jupiter there is
so much pressure that hydrogen is
believed to take the form of a metallic
liquid and this metallic liquid hydrogen
generates an incredibly powerful
magnetic field almost 20,000 times
stronger than Earth if you measure at
the same distance away so if you could
see this magnetic field from Earth it
would appear twice as big as the full
moon on its own that magnetic field is
harmless but right in the middle of it
is the most volcanically active world in
the solar system Jupiter's moon
IO the volcanoes on io's Surface shoot
out tons of sulfur dioxide and every
second one ton of this material gets
ionized and trapped inside Jupiter's
magnetic field and the field accelerates
these particles to rotate incredibly
fast with Jupiter so they whiz around at
over 300
km/s their inertia actually pulls back
on the field stretching it out and this
trap material slams into other moons
ejecting even more particles from their
surfaces this cycle forms massive
radiation belts which span past Europa
and the other moons of
Jupiter now for electronics this intense
radiation is Kryptonite in the 1970s the
Pioneer 10 and Voyager missions only
briefly passed by Jupiter but the
radiation caused glitches gave the
instruments false commands and corrupted
some of their data even with modern
shielding a spacecraft within the
radiation belts would only survive for
around 3 months so how will NASA's new
Mission the Europa Clipper orbit Europa
for over 4 years without getting fried
well the solution is it won't it'll
orbit Jupiter from afar and then swoop
in every few weeks to quickly fly by
Europa and then leave again and since
the mission is going to collect a lot of
data it can use the downtime while it's
way out here to transmit it all back to
Earth before going in for another swoop
in all it'll do 49 flybys mapping almost
the entire surface that's actually how
the Clipper got its name after the fast
and Nimble 19th century clipper ships
quickly dipping in and out of ports
but of all the places in the solar
system to look for life why Europa if
you stood on europa's Surface you'd be
hit with 5400 Mills of radiation in a
single day that's 1,800 times more than
the annual dose here on Earth if you
stay here for a couple hours you would
eventually die from radiation sickness
but Europa contains a
secret when Voyager 1 passed by Jupiter
in 1979 it took this photo of Europa if
you compare that to most of the other
moons in the solar system you'll notice
something is
missing craters every planet and moon
has been bombarded by asteroids over
billions of years and most planetary
surfaces show it but not Europa so why
not well something recent say over the
past 60 million years or so must have
been happening on Europa to erase
most of these craters from the
surface 16 years after Voyager Galileo
arrived to Jupiter it spent 8 years
studying both the gas giant and its
moons and Galileo's magnetometer picked
up something interesting on Europa
Jupiter's magnetic poles like Earth's
aren't aligned with its Geographic poles
so as the planet rotates every 10 hours
the whole magnetic field
wobbles this Chang ing field from
Jupiter induces a magnetic field on
Europa and a relatively strong one at
that that means there must be an
electrically conductive layer within
Europa that reacts to Jupiter's field
and readings from Galileo indicate that
it must be somewhere close to the
surface only tens of kilometers
deep so what kind of conductive
layer well europa's White surface is
almost entirely covered in a thick crust
of water ice these reddish brown regions
when observed through a spectrometer fit
the description of a lot of things like
hydrated salts sulfuric acid or even
bacteria we need more data to be sure
but recent experiments at JPL found that
sea salt when bombarded with intense
radiation turns from white to this same
brownish color found on
Europa so scientists suspect that
there's a whole saltwater ocean inside
Europa that could be 100 km deep meaning
Europa would contain twice as much water
as the whole of the earth and it must be
driving geological activity that
constantly Smooths out and renews the
surface of the
Moon but the Jupiter system only gets
about 4% of the sunlight we get here on
Earth so europa's surface is constantly
below 160° C so you'd expect the whole
whole ocean to be frozen solid but
there's a way to generate heat that
doesn't rely on the sun and I've got a
little demo here to prove it europa's
orbit around Jupiter isn't a perfect
circle this is because IO Europa and
ganam are all in orbital resonance each
time ganam completes one orbit Europa
completes two and IO four because of
that IO tugs Europa inward on one side
of the orbit while ganam pulls it out on
the other making its orbit more
eccentric now Jupiter's pull is stronger
on The Closer side of the orbit than on
the farther side so Europa is constantly
being stretched and squeezed stretched
and
squeezed and you can see how this rubber
ball gets warmer as I squeeze it
scientists believe that the friction
caused by the tidal flexing of the
entire Moon can generate enough heat to
keep the o ocean liquid this effect gets
stronger the closer you get to Jupiter
which is why IO is so volcanically
active so you can see this ball is
significantly hotter now I held on to
this ball at the same time to make sure
it wasn't just the heat coming in from
my
hand what sort of temperature of the
ocean are we thinking so it depends on
how salty it is so melting temperature
of of ice or maybe depressed by 10° C
below that if it's a very salty ocean
similar to to cold oceans on Earth and
how would the flexing differ if there's
this big liquid ocean versus if there's
no ocean there if there's no ocean
Europa should Flex by only about 1 meter
in amplitude but if there's an ocean in
there then it flexes with an amplitude
of 30 m so that's an enormous deflection
and that will come out pretty clearly in
the gravity data another argument for
how thick the ey shell is we see these
very strange features on the surface
that are aru in shape but like multiple
arcs put together we call them cycloids
and not something you'd expect to see on
an icy Moon and we think they form if a
crack propagates at just the right speed
about the speed someone would walk and
is following the changing stress field
of Europa being squeezed as it orbits
around Jupiter and if there were no
ocean down there there wouldn't be
enough of an ampl itude of that motion
to explain the cracking but if there is
an ocean then it could explain the
cracking all that tidal flexing pushes
magma in the outer core up closer to the
seafloor water flowing through the crust
above it is heated and it picks up
minerals from the ground ejecting them
into the ocean this creates hydrothermal
vents and where we find these on Earth
we also find life thousands of meters
below the surface with no sunlight these
vents are oases for ocean life the life
forms down here rely on unique bacteria
bacteria that feed on the minerals from
the vents rather than from the energy
provided by the
Sun how long are we thinking that Europa
has had an ocean it could be 4 billion
years we don't know for sure that amount
of time could give life the opportunity
to evolve in those oceans right exactly
right organisms can use
methane carbon dioxide sulfur reactions
any chemical reaction you can think of
that might happen in the ocean can
potentially be used as a fuel for that
organism's metabolism so we're not
talking about searching for fishes or
whales or squids or something down there
but looking for single cell
organisms we were so concerned there
might be life on Europa that when the
Galileo mission was ending in 2003 it
was deliberately crashed into Jupiter to
avoid the risk of contaminating Europa
but Clipper will not be able to drill
through the kilometers thick ice crust
so how are we going to find evidence for
life beneath that thick
surface this is the snotbot it's a drone
with Petri dishes glued to the top and
it flies right through whale blows to
collect whale snot right here on Earth
and zoologists can use the snotbot to
retrieve all sorts of info on a whale's
biology
and it turns out we can do something
very similar for celestial bodies too
we've actually captured images of water
geysers shooting out of Enceladus a moon
of Saturn housing a subsurface Ocean and
the Hubble Space Telescope has picked up
some evidence of what could be similar
geyser eruptions on Europa the hope is
that Clipper could fly through one of
these plumes like the snotbot and reveal
their chemical composition using a mass
spectrometer but evidence for an ocean
on Europa isn't conclusive Enceladus
seems like a stronger candidate we have
actual images of its plumes and we've
even flown through them we are almost
100% certain there's a subsurface ocean
there if we have these plumes on
Enceladus and there's clearly maybe a
liquid ocean there why does Europa have
your attention more than Enceladus is
there is there something that draws you
we don't know how long it takes life to
get going but it's possible that
Enceladus may have just kind of started
up its engines uh whereas Europa is more
likely been well evolved over a long
time surprisingly being bombarded by
Jupiter's radiation actually makes
Europa a better candidate see those
highspeed particles hitting europa's
surface give water and carbon dioxide
molecules enough energy to form new
compounds like falahi or hydrogen
peroxide and these can serve as food for
Life beneath the surface if they can get
down that far and we have evidence of
overturn of the icy Shell at chaos zones
where the icy crust seems to have
collided and and material has been
shoved into the icy shell so there may
be ways for this fuel for life to get
down into the icy shell and potentially
to the ocean and Clipper doesn't have to
touch down on the surface to confirm
this there's a red spectrometer to look
at the chemical Fingerprints of light
bounced off the surface to help identify
and map out where the salts are find if
there are Organics there there's a
ultraviolet spectrograph that's aboard
the spacecraft to look for plumes are
they there and of course then can we fly
through them and then there'll be
Imaging of essentially the whole globe
at better than 100 m per pixel
resolution so one camera will take swats
of images as we fly over the surface and
that's called the wide angle camera and
then the other camera is the narrow
angle camera from 50 kilm altitude it
will get half meter per pixel images
right so it'll be able to resolve my
desk here if it were on Europa and then
it would be a future Mission like a
Lander that would go and and actually
search for signs of Life at Europa do
you think a Lander would have a chance
of survival there have been studies that
say we can get a Lander living on the
surface for month if we think that's
sufficient to go in there scoop some
stuff up from below the depth of
radiation processing and put it into a
mass spectrometer and see what we see
but the Europa Clipper won't be studying
Jupiter's moons alone the European space
agency's juice Mission or the Jupiter
icy moons Explorer is already on its way
to Jupiter it will come to the system
just 15 months after Clipper and it'll
even be doing a few flybys of Europa
before settling into a tight orbit
around ganade so the European Space
Agency will also have a mission there at
the same time yes we're having informal
conversations with members of the juice
science team what would it mean to have
two spacecraft there at the same time
the juice Mission will end up in orbit
around ganam and ganam has its own
magnetosphere well we'll be outside
ganimedes magnetosphere so we might say
oh look there's this big burst coming
from Jupiter and then and Juice might
say oh we felt that over here in our uh
magnetic signals so we wouldn't have to
really do anything different except talk
to each other and make sure that the sum
of the of the hole is even bigger than
its
parts Europa Clipper was scheduled to
launch on October 10th 2024 but NASA is
waiting for Hurricane Milton to clear
Florida before the spacecraft can take
off
safely when will we get the first
results you'll start seeing distant
observations coming in in 2030 as we
look at Europa from afar and search for
plumes and then you'll see the first
really high resolution data in 2031 so
after say 26 years of thinking about a
mission to Europa how does it feel to be
so close to launch it's a little surreal
I must say this has been such a long
time coming it's occasionally hitting me
that our spacecraft is going to be up
there in the heavens right on its way it
turns out that during a Europa ocean
conference in the late '90s NASA
actually video calleded arur SE Clark
and after showing him plans for a future
mission to explore the farway ocean
World Clark finally gave NASA permission
to land on
[Music]
Europa Europa Clipper is a perfect
example of the amazing things we can do
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