Welcome to NASA's Science Live.
This is your opportunity to interact with NASA experts
and have your questions answered in real time.
I'm your host to Hera Allen.
Today, we're exploring NASA's Juno mission,
which has been orbiting Jupiter for almost eight years.
This has given it the unique opportunity to study two
fascinating moons, one boasting lakes of lava on its surface,
and the other thought
to have a global liquid ocean hiding beneath its icy crust.
Let's dive into the worlds of Europa and IO.
Earlier this year, the Juno spacecraft conducted two ultra
close flybys of Jupiter's
volcanic moon IO capturing a wealth of data
and the highest resolution images of its surface in over
two decades.
These flybys are the closest
that a mission has come to the surface
since a visit by the Galileo spacecraft in October 2001.
The maneuvers have allowed Juno to study the most volcanically
active world in our solar system,
which is also only a little bit larger than Earth's moon.
IO is caught in a tug of war between Jupiter's powerful
gravity and the smaller pole from two neighboring moons.
This constant stretch is turning its insides, creating
volcanic eruptions and lakes of lava that cover its surface.
Now, if IO is the world
of fire, you can think of Europa as the world of ice.
And just earlier this week, scientists
released a new estimate
for the amount of oxygen that's being produced on this moon
using data collected by Juno in 2022.
Europa is the destination of our upcoming Europa
Clipper mission
that's launching later this fall and is a world
that is great of great interest to astrobiologists
searching for signs of life in the universe.
Scientists are almost certain that a vast ocean lies beneath
Europa's icy shell, as well as other ingredients
for life as we know it, like chemistry and energy.
These new findings are helping us better understand if this
icy moon has conditions that could be favorable to life.
Let's see how scientists are using Juno data
to unravel the mysteries of this fascinating world.
Now, if you have questions throughout today's show,
you can submit them using the hashtag
AskNASA on social media or you can drop them
directly into the comment box wherever you're watching.
Today, we're joined by two special guests
who are going to be answering those questions live on air.
We have Dustin Buccino, a NASA's Juno mission
engineer and scientist.
Welcome Dustin.
Thank you.
Thanks for having me.
And Dr.
Rosaly Lopes,
a volcano expert and NASA's Juno associate team member.
Welcome, Rosaly.
Thank you.
And it's a pleasure to be here.
And thank you both so much for being here with us today.
Can you start off by telling our viewers
a little bit about your individual roles
with the Juno mission? Dustin, let's start with you.
So what I do, I have two hats on Juno.
I my first role is the Gravity Instrument Engineer.
So I'm responsible for collecting all of the data
and processing the data for the gravity science investigations
we do,
which is measuring
the interior structures of Jupiter and its moons.
I'm also a part of the Science Planning Working Group,
where we take all of the science objectives that we want
to accomplish on any given orbit around Jupiter and combine
them into a cohesive plan that we can give
to the engineering team to execute.
And what about you, Rosaly?
I also have two hats.
The first is my job here at
JPL is depth to direct for the Planetary
Science Directorate, and Juno is one of our missions.
So the success of Juno is very important to me.
But the other, which is actually more fun,
is a collaborator on the science of Juno.
Scott Bolton, the PI of Juno and I
worked together back on Galileo days,
and because of my expertise on the year, he invited me to
help out the Juno scientists and.
And that's been great.
You know, Rosalee, talking about your expertise
with IO, I know you've done a lot of research on this moon.
Even winning a world record for the amount of active volcanoes
you've discovered.
Can you tell us why is NASA's so interested in this world?
IO is a really interesting
and rather weird, unique moment.
It's the most volcanically active object
in the solar system.
We may think that the Earth has a lot of volcanoes, but
IO has bigger volcanoes, bigger lava flows that erupt
all the time.
Gigantic plumes, volcanic plumes above the surface.
And them.
And we think that
some of the eruptions on IO,
a very similar to the eruptions on the earth
in the Earth's early history,
like hundreds of millions to billions of years ago.
And even the composition of the lava
may be very similar to premier lava on the earth.
So looking at the IO gives us a way to
look at the early earth and study
eruptions that don't exist anymore on Earth.
That is so cool to think about.
And so I understand too, it's due to IO any position
in this Jupiter system that really has to deal
with its volcanoes and its inner mechanics.
And so, Dustin, I know you focus a lot on the Jovian system.
So again, Jupiter, its rings, its moons.
Can you explain the significance of IO
and Europa within this system?
So IO drives
so much of what's happening in the Jovian system.
As Rosalie mentioned, IO has a lot of volcanoes
and it erupts and and creates these, these
these plumes which are then create the atmosphere of IO
this atmosphere gets stripped away because Jupiter is rotating
very quickly and has a large magnetic field.
And Jupiter's magnetic field actually takes
these particles that are being erupted by IO and emits them
and ionized them into the magnetic field.
And once they are ionized and charged,
they get to move around along these magnetic field lines
and they create these large amounts of plasma
that then are move around
the Jovian system creates radiation hazards
for when we fly our spacecraft through there.
But also these particles then get in the right position.
They get moved along
the magnetic field lines into Jupiter itself,
and they hit
Jupiter at the poles and create these massive auroras
just like we see on Earth.
But the auroras,
there are auroras on Jupiter that are that are even larger.
And it puts a lot of energy into the into the Jovian atmosphere
through this mechanism.
And it really is a full circle approach to this.
And so I want to
now pivot a little bit and talk about Europa.
So just this week, NASA's released New Science
from Juno's 2022 flyby of the moon.
And this data indicated that the ice covered moon generates
1000 tons of oxygen every 24 hours. So
that's enough to keep a million humans breathing for a day.
Dustin, what is the key takeaway here?
So the key takeaway here is really,
you know, Europa is producing oxygen.
And one of the
interesting things about Europa is that the surface is ice.
And underneath that surface
we believe there is a large liquid water ocean.
And on earth here where there's water, there is life.
And and we believe that could be the case on Europa.
So we want to find out how habitable is Europa.
Now, this paper looked at a very interesting way
of figuring out how much oxygen
production there is
when these
same charged particles that I just talked about
that are moving
around the Jovian system impact that ice on Europa,
it splits the ice which is composed of hydrogen and oxygen
combined H2O, it splits it into hydrogen and oxygen,
and some of that oxygen
can propagate through the ice into the ocean of Europa,
and that creates the potentially conditions for life.
I mean, just some
fascinating workings going on on these two moons.
And we have a ton of questions
coming in from our viewers online right now.
So let's hop right into this Q&A
as a reminder to those watching live.
You can submit your own questions for Dustin and Rosalie
using the hashtag Ask Nassr on social media,
or you can drop your question
directly into the comment box wherever you're watching.
All right.
Our first question is from Andrew Kate Tyler on Facebook
who asks, Where will Juno go after IO Destin?
So Juno is continuing to orbit around Jupiter
and every time we orbit what IO did to our orbit
was actually when we flew by IO in 2020 and December 2023,
and in February of this year it actually shrunk
our orbital period.
We were in a larger orbit and IO we did a grab.
When we fly by that close, it alters Juno's trajectory.
And so we're actually going to think our bit.
And so we're going to be
by Jupiter faster than we used to be, and we're going taking
of Jupiter to understand this
interior structure and its magnetic field
and all these particle pulling that occur close in.
And so as a follow up,
we have Redman on YouTube who as
you know, we've been studying IO with Juno.
Are there any ice volcanoes on Europa?
Rosalie.
good question.
Yes, we have seen features
that can be interpreted as ice volcanoes.
So we call this Cryovolcanism because it's called volcanism.
Essentially, volcanism is the process that brings
material from the interior to the surface.
So if you're interior has
magma like IO and S, then
when it comes to the surface, that molten rock will be lava.
But because it ropa has liquid water under its ice crust,
what comes to the surface is
either a plume of vapor
or a sort of slushy ice.
You can think of it that way and it's
there have been a number of
studies, even some evidence showing
that plumes may be erupting from a rope.
But, you know, we haven't found that
that proof yet.
And that's one of the things that the Europa Clipper
will be looking for.
Both evidence of Cryovolcanoes on the surface
and also plumes coming out of the surface.
And so while we're on this topic of Europa,
we have Rittman on YouTube who asks, Is Europa
pulled like IO with this gravitational pull?
Dustin?
Yes. So the mechanism
that we talked about on IO, which is this type of we
we call it tidal heating, and so the orbit around that,
that IO and Europa take around Jupiter is not perfectly
circular, it's off by a little bit.
And so when the moons get closer to Jupiter they are
they are subject to what we call tidal heating
so that the moon is essentially
being pulled by Jupiter and squished almost.
And that creates some heat.
And that heat creates on IO the molten the molten rock
that we see in the volcanoes
and on Europa, which is farther away than IO.
And so it's, it's not as large of a magnitude of effect,
but it's still there.
And that tidal heating creates the liquid ocean that we believe
exists under the crust.
That's incredible.
And so we do we have Benjamin Wilson on Facebook
who wants to know
how are we going to get under this icy ocean, under this ice,
the ocean of Europa, And will we be able to do it remotely
best And you want to take that one.
So there are there are ways that we can look
under the surface without having to go there.
We would obviously love to go there and just, you know,
look at the water and look at samples.
But we can do what we call remote
sensing techniques to sort of look under the surface.
So the Europa Clipper spacecraft and Juno have instruments
that are able to do that.
So what I work on is the is the gravity science.
And so that's measuring the interior
structure of these moons
and measuring this tidal heating effect that occurs.
And we can do that
by essentially measuring the position of the spacecraft.
And we measure the position of the spacecraft
very precisely with by measuring
the Doppler shift to earth on the radio signal.
And from doing that, we're measuring essentially
a spacecraft's position, velocity and acceleration.
And that gives us how much gravity was experienced.
And so if you're standing on the surface of Earth, you're
you're being pulled by all the particles around
you all the way to the center.
And so if
we measure this gravity field on a global scale around
the two moons,
we can actually determine what the interior structures
look like and how much liquid
there is relative to solid and what kinds of solid points.
The density of the solids.
Other instruments
such as Juno's microwave radiometer are able to look
a little bit below the surface
to see differences in the ice at depth,
and missions like the Europa Clipper will have an ice
penetrating radar to look below the surface as well.
So we're talking a lot about
how we're going to be studying this.
Moon But Rosalie, can you give us an idea of why
Europa, why, why is NASA's so interested
in going to this ice covered Moon
And we're very interested in the Europa
because it's what we call a notion world
and a rope a rope as Ocean may actually have.
Life is one of the most
promising places in the solar system for life.
You know, as we were saying before,
there is this tidal heating.
And so rope as interior also suffers
don't to a much lesser extent denial from this tidal heating.
There may be a volcanism
in the in the deep interior of a rope.
If you have water, you have heat energy.
Those are some of the ingredients that
you'll need for life.
And the Galileo mission actually was the mission that found the
that a rope had this liquid ocean
under a nice crust and became very, very excited.
Well, it's
it's so exciting again to to think that we're now,
you know, months away from launching back
to studying this moon with Clipper.
And I want to take us back to Juno now.
So we have liberty on YouTube.
Who asks,
how did Juno manage to function way past its intended lifetime?
Dustin
So Juno.
Juno was designed to last a certain number of orbits
around Jupiter, and we've lasted a lot longer than that.
And Juno is a very well-designed spacecraft.
We designed the spacecraft to go to
this intense environment around Jupiter.
It has a vault that protects all of the electronics
from Jupiter's radiation in the space environment,
essentially bringing what would be, you know,
a death sentence to a computer
and preventing it from being hit by all these particles.
And so Juno has been, you know, we fly the spacecraft
very well and safely,
and we keep monitoring and and watching for these effects.
And, you know, it's all a matter of the engineering
and how well it was put together.
And so it's a very well built spacecraft,
and we're seeing it last longer because of the way we fly it
and because of the design with the radiation from.
And so I have a great follow up really quickly,
Mohammed, on the on Facebook, who wants to know
what is the velocity of Juno in orbit?
Okay.
So Juno is in what we call an elliptical orbit.
It comes in very close to Jupiter, only once per orbit.
And when it is close to Jupiter, it is traveling at around
50 kilometers per second is very, very fast.
And so we
that is also how we have survived so long around Jupiter.
So if we go in really fast, we collect our data
and then get out
and then we have a lot of time away from the intense radiation
to send the data back
and do remote observations from a distance.
And so that is that's how we are able also to help with that.
And Rosalee, we have a shark who asks,
how much longer will Juno be active?
well,
that's maybe more of a question for Dustin, but, you know,
it's there are limits based on the amount of radiation
that Judah can withstand, you know, and, you know,
and there is always the limit of funding as well.
But we hope that Juno will be around for a while longer.
And this missions, by the way, they
they are very well engineered and they tend to last longer
than we then we think, for example,
Galileo lasted a lot longer.
The Mars Exploration Rovers, again,
you know, last a lot longer than we expected.
So we build them well.
And the you know, we
put put the lot of
work and and thought into that engineering
because these missions are very expensive
and you know, so if they last longer,
you get more out of them.
Absolutely.
And so I have a great follow up.
You know talking about this incredible engineering.
We have tailored t69420 on x who asked
what kind of radiation hardening is used
to allow probes to survive the Jovian system.
Dustin
So the the the quick answer to that is
several hundred
pounds of aluminum in titanium
to protect all of the electronics.
The Juno mission has what I called this radiation vault.
And it is it is composed of titanium to protect
all of the electronics that we put in to Juno.
And so that's one step.
The other step is all of our
spacecraft that we design have what we call redundancy in them.
So if a
if we get hit by radiation or if we get hit by a particle
or something that causes damage to
a component on the spacecraft, all of the critical components
of the spacecraft, there are generally two of them.
So we have two radio communicators, two ERs, me,
two radios to Earth.
We have to computers, you know, to data
handling systems and all of these.
So one goes down.
In fact,
the spacecraft will autonomously detect that something's wrong
with what's happening and it will switch to the what
the backup.
And so we can either command that to happen
or if it happens and and the spacecraft thinks it's
going to end up hurting itself by maintain trying to use
the current device, it will switch to the other one.
And so we have this what we call redundancy.
And we also have the radiation hardening.
It is fascinating to honestly hear, you know,
just the engineering involved in these spacecraft missions.
Justin, can you tell us how long from maybe like concept
design to build, finish did it take to even come up
with Juno?
I don't.
I've I've been on Juno since orbit insertion.
So that's it's been a since 2016.
Just prior to that as when I started
before that you know, the mission launched in 2011
and the concept and design and proposal
was many years before that.
So these are these are decades long projects
that that that takes it takes a lot of time to design
the mission, the concept, put it together and build it
and then launch it.
And once you launch it, you still have to wait
a very long time to get to Jupiter.
And so this is often a decades long process.
Yeah.
And so going back to this, you know,
always the radiation question and how we're protecting
spacecraft against radiation from Jupiter
is could this technology be used to protect humans
if we one day venture out there ourselves, Rosalee
or Dustin, for that one?
Well, if we if we go to Europe
or IO, we're certainly going to have to protect the humans.
I mean, the the radiation, those Apollo would kill
you in a day, so
you would have to protect the humans very well.
And I'm not sure what exactly
you would use, but maybe by then
we'll have even better ways or better materials.
Dustin, anything to add?
Yeah.
I mean, you know,
when Juno flies by Jupiter, we get about 150,000
dental X-rays worth of radiation in a very, very short period.
It's a lot of radiation.
And so we definitely would need to protect.
And, you know, right now we're using metals to do that.
But as Rosalee mentioned,
maybe there will be future materials
that we will discover that will help us
protect humans.
And so to your mention it, like when talking about
Juno flying by Jupiter, we have 20 on YouTube.
Who asks, what is the propulsion that is used on on Juno,
and how do you navigate between these moons and Jupiter?
Dustin
So we use well, just standard on Juno.
It's just what we call standard chemical propulsion.
It's just it's, it's a rocket.
We use combine fuel and oxidizer together and burn
and through the rocket nozzle.
And that provides us thrust.
Juno is a very elegantly designed emission in that
we don't need
to do a whole lot of that while we are at Jupiter.
We use a lot of fuel to get there
and to enter orbit in 2016, but that we're there.
Juno is mostly on what we call a ballistic trajectory.
So what we do is we fly the spacecraft
and Jupiter pulls on it, the moons pull on Juno,
and that just naturally causes the spacecraft to keep flying
in a particular orientation.
Every orbit
we take analysis of what this of what
the spacecraft's position is, and we measure that by sending
a radio signal from Juno to Earth at a given frequency.
And we know when that was sent
and what frequency it was sent at
and what we when we receive it on earth
at these massive antennas
at NASA's Deep Space network, we can receive that signal.
And the frequency we received is different than what was sent.
And so that tells us the spacecraft velocity.
And then it we also know when it was received.
And so if you know,
when the signal was sent and when it was received,
that's the distance to the spacecraft.
And so we measure what we call range and Doppler measurements
to determine the spacecraft's trajectory.
And then we can carefully navigate that spacecraft to
where we want to go
relatively close to what that ballistic trajectory was.
So we make little corrections every single orbit
in order to maintain what we want to do for our science.
And so I want to take it back.
We have a lot of interest coming in right now on Europa,
and I have Carrie Ann on YouTube.
Who wants to know,
will there ever be an attempt to get samples from the plumes
on Europa?
Rosalee Yeah, I can take that.
That's a very interesting question.
But the problem with plumes on their rope
is that, well, first of all, we still have to confirm
that this plumes idea and and they seem to come and go.
So you can't really plan a sample collecting mission
unless you actually know that the plume
is going to be there for a long time.
So, in fact, we are doing a study
at the moment about the sample, collecting a sample,
collecting mission to collect
a sample from IO, because on the air, we know that
there are some plumes that last a very long time.
For example, one of them, the Prometheus plume, was active
when Voyager field flew by in 1979
and every mission that flies by
Galileo, New Horizons, Juno,
everyone sees Prometheus being active
so that you can plan for it because you it's
a reasonable assumption that the plume will still be active
or able to give us a little details
on like how this sampling
mission could work.
Well, you would have to send a spacecraft there.
We have ways of collecting samples while
the spacecraft flies through a plume.
And the and and then the spacecraft
comes back to Earth, drops off the capsule, and
and then that's on the list in laboratories.
We we can send very good spacecraft to the planets.
But we can't send the kind of instrumentation
that we have on the laboratory is on Earth.
And and that's why, you know, we have been
collecting samples from asteroids like Osiris.
Rex has come back with samples that that being analyzed now
and also the Hayabusa missions from Japan
and bring back rocks from Mars
so they can be on the list in laboratories on this.
And so sticking with this
topic of science of these two moons, J word on YouTube asks,
Is there any tectonic plate activity on either Europa or IO?
And if so,
what kind of natural formations have formed due to it?
Rosalie
If I can take that.
We see mountains on IO, but C mountains means
there is some tectonic activity, but not plate tectonics.
And on the rope we see a lot of faults
on the cracks on the surface and the and people
who have studied those cracks and the morphology
say that, okay, the crust has been in a crack.
Then these pieces have moved around
because they're floating on top of the ocean.
So it's a little bit like you, you see on earth with,
you know, ice, for example, near Antarctica.
And but plate tectonics is something that we have not seen
on any other body outside the earth.
So that seems to be very specific to the earth.
And the is a very interesting question
about why may be because we need
a lot of water enough for this to lubricate
this plates, particularly in the sub subduction zones,
one plate diving under the other. We
need perhaps a certain
thickness of crust relative to the size of the planet.
So, for example, one, you know, a rope of the
the ice may be is to sand, although there have been
suggestions of subduction on the ropes,
it's possible on Mars, the crust is too thick.
So you need that kind of Goldilocks
for plate tectonics to take place.
And a great follow up we have universe on actually
wants to know how thick is the ice layer on Europa?
Dustin
So we don't really know exactly for sure.
That's one thing that we want
to get a better answer to is how thick is it truly?
But we believe it's on the order
of something like 10 to 20 kilometers.
Wow. And
so taking it back to Juno,
what are the tools that Juno has on board?
This is from scientific potato.
So Juno has
a lot of instruments on board, and Juno's instruments
were designed to look at Jupiter primarily.
And so we have what we call the gravity science,
which is what I do, which is tries to measure the
the gravity fields of the objects
that were flying by Juno also has a microwave radiometer
which probes the atmosphere of Jupiter and also, of course,
the structure of the surfaces on the moons.
We also have a magnetometer at the
at the end of the boom there.
The one solar panel that looks a little different
is the magnetometer, the magnetic field of Jupiter.
We also have a couple of cameras.
We have an infrared camera called Jiram, and we have a
visible camera called Juno Cam.
There's also a suite of particle
sensors, high energy and low energy particle detectors.
And then we also have
a plasma wave sensor instrument which measures the
the the electrical fields that the spacecraft is experiencing.
And I think I missed and I might have missed one or two,
but we also have another star camera that looks at at the at
the both Jupiter and the moons.
A little more detail.
So all in all, though, we have a ton of science going on
and we have on YouTube who has given the signal delay?
How are you able to control Juno?
Dustin So Juno we don't actively control Juno
as if we're, you know, we call it.
We're not joy sticking it.
We don't send it a command and wait for wait for it
to do it, and then we send it back.
It takes 45 minutes, roughly,
for a signal that we send from Earth to reach Juno.
And then another
45 minutes for it to come back all the way to earth.
So we can't actively control the spacecraft in that way.
What we do is we send it a command of a sequence
command, which generally lasts about a week,
somewhere between one week and four weeks long.
And it's generally covers one orbit around Juno,
around Jupiter,
and that that command sequence instructs the spacecraft to do
everything that it should do in that time period.
So whether it be a week, whether a month,
it does all those commands within that time period.
And so every time it's while we're already
well, it's executing a one month plan or a three week plan,
we're already planning the next one
and we're generating that set of commands.
And so it all will happen.
On that cadence,
there are times where we will command it more frequently
and those are for things like when we're doing
these orbit correction maneuvers
or if there's an anomaly and we need to respond to it,
we then send commands on a more frequent basis.
But the general structure is you,
you it's it's largely just flying there an automated
on this command set.
Well,
and so I have a follow up for you, Rosalie.
It's elevated one on YouTube.
Who wants to know how powerful is Juno
now compared to the Voyager spacecraft, for example?
Well, I wouldn't say
powerful is a is the right term.
Voyager flew by so Voyager was a flyby.
It flew by the Jupiter system.
So the amount of data it could take was limited.
Now, Galileo
was a Jupiter orbiter like Juno, so Galileo
got a lot of data, you know, on the ropes and IO.
But the
the the more recent spacecraft, of course, have more
of later technology and better instrumentation.
So you'll always get a lot of improvement.
And also the previous missions tell you what
science questions you're trying to answer.
So when you design the next mission, you're going like,
I want to answer these science questions that
we couldn't answer with the last mission.
So you tailor your instruments to those science questions.
And the science questions are always the starting point
for any new missions or any new mission planning.
So, you know,
Juno is gathering
a lot of except of data on the on there
Ropa and IO that Voyager could not get to because
when Voyager flew by
Voyager was a very exploratory mission.
It didn't even know what it was going to find.
And for example, with the robot clipper,
now we know a lot more about it.
Roper from Galileo
and somewhat more from Juno as well.
And so the instruments were designed,
you know, for example, radar
to tell you about the thickness of the ice layer.
And I will stress that Juno was not designed
to look at the satellites.
So this was really a great opportunity.
And and I think Dustin can talk more about that.
Yeah.
So Juno was designed to look at Jupiter, and
in the original mission we would not be actually flying
by any of these moons because Juno has lasted so long.
We now have this unique opportunity
and we
of course we were going
to take advantage of that to fly by these Galilean moons
in order to look at them in more detail.
And so talking again about just instruments
and the science that is building on top of each other,
we have a question from Justin on YouTube.
Who wants to know what instruments and techniques
could be used to check for life on Europa?
So instrument wise, we'd be.
There's no such thing right now as a life detecting instrument.
Life is very complex on earth and we can look and detect.
But what we're actually looking for is
what are the conditions to allow for life to exist
and do those exist on Europa as an example?
So what I really look at is Europa potentially habitable.
So on Earth we we can go and look at all
of these extreme locations
and in general, everywhere we look on earth there is life.
And so
what are the conditions on Europa and are they compatible
with the conditions that we know of that life could exist?
And so we're looking at
things like temperature, a chemical composition
of the of the ocean and the surface, the icy surface
to sort of to determine, you know, what is it habitable.
That's the real question we're trying to get at.
And I really that, you know, a lot of instrument
developers and engineers and future future
engineers can come up with these new ways
to develop techniques to actually detect life.
And I have a great follow up to that.
You, Rosalee, we have Connemara on YouTube.
Who asked what is being done to potentially protect
the life that could be present at Europa?
that we have
what we call planetary protection,
in fact is a is a kind of international agreement that.
We're going to protect this world.
And so we take planetary
protection very, very seriously.
Now, for example, some people ask
why we killed the Galileo spacecraft
by sending it inside Jupiter
and we killed
the Cassini spacecraft by sending it think side Saturn.
And the reason was planetary protection.
Galileo found that
it could possibly have life, so we couldn't risk
living it around the Jupiter system.
One, they could crash on Europa and the spacecraft had not
been sterilized.
So we thought the best way, the safest way is to kill it.
Same thing with Saturn that the Galileo
mission sorry, the Cassini mission, found that
Titan ending celibate might have life.
So again, in the end, we killed the spacecraft
by sending getting side Saturn so it would not contaminate.
So I been through two of those because I worked
on Cassini as well.
So maybe Dustin can talk more about Juno.
And so for Juno, we of course
have the same planetary protection requirements.
And, you know, after our mission
that the extended mission is over,
we will have to do something to protect Europa
and the other moons from our spacecraft, which was built,
you know, very cleanly.
But we don't want to take that risk.
You know,
we don't want to go to Europa in 20 years
with these amazing new technologies
that we would be developing and only if and say we found life.
And it turns out it was we brought it there.
We didn't we don't we don't want to do that.
So we will have to find a way to protect Europa
and we are already working on that.
And what's the best way to prevent, you know,
Juno from impacting Europa or contaminate it
now? Blue Lightning on YouTube has a great follow up.
Who wants to know
if we ever do discover life in Europa's oceans?
What kind of life would we be expecting?
Rosalee
well, we don't know that,
but we don't think that we would find whales.
We are expecting
microbial life, so,
you know, not, you know, not whales,
although sometimes we joke about whales on the
on the roper, but no, the life
would likely be primitive.
We find life, for example, in the Earth's oceans
very deep around hydrothermal vents.
So may be that something that we might find on the rope,
but we're a long way from speculating.
I mean, what kind of life we would we would find there.
But what's something that's I find very interesting
about life is that it usually finds a way we
we find life in places on earth that we wouldn't expect.
And, you know, for example, decades ago,
no one thought that life could exist in this
deep, deep into the Earth's oceans until the discovery
of this hydrothermal vent some life around them.
And a colleague of mine once said this
No one had ever seen a fish.
You wouldn't think that life could exist in the ocean.
So we don't know what we're going to find.
But that's that's what makes it so exciting.
Yeah, that's part of the journey.
And so, you know, Dustin,
I understand you do study, you know,
the inner workings of Europa and the Ocean.
And so I have a great question
for you from Strong Monty on YouTube.
Who wants to know?
Wouldn't the Ocean of Europa
already have plenty of oxygen if it is H2O?
That's a great question.
You know,
H2O is water.
We as humans and life can't breathe.
H2O directly unless you are something like a fish.
You need to be able to have oxygen itself.
And if you you can actually dissolve oxygen and water.
And so that also is where it comes into is
you can actually pull those oxygen molecules separately out.
And so why does it need more oxygen
from the surface to be able to support life?
Well,
we just think that's the
one of the mechanisms that oxygen can get into the ocean.
We will learn a lot more
from Europa Clipper when when it gets there.
On how that happened.
All the mechanisms that may that may generate oxygen.
And so we've been talking
a lot about these observations from orbit.
And I have a question from Ilja.
What like Hill Bend Hand on Facebook wants to know,
is there a way to zoom in really close on
either of these worlds and see what's on the ground,
Rosalie or Dustin?
So so, yes, you know, if you have a camera
that can do that, you absolutely can zoom in.
And Europa Clipper has a
what we call a narrow
angle camera, which is essentially more
just like a camera with a telescope.
And it can zoom in very closely on the surface of Europa.
A lot of the resolution that comes out of pretty
any flyby from any spacecraft is how far away are you from
the moon.
And so the closer you get, the higher resolution
image you can get.
And so with Juno,
we got about 350 kilometers from Europa's surface,
and the Junocam instrument took many amazing
photos of the surface at very high resolution
and certain regions to help fill in the gaps,
so to speak, of, of from what we had previously.
And Europa Clipper is going to get even closer to the surface.
So we're going to really be able
to zoom in and see very, very high resolution images.
Wow. And we received some pretty high resolution
images recently, right, from Juno with IO.
And so I understand there is a
there is a public engagement component of this mission.
Right.
Dustin, could you talk a little bit about it? Cam?
So Cam is an instrument that's a camera.
It's not too dissimilar actually,
from your cell phone's camera in a way.
And what it does is it takes pictures
of, of the various moons and Jupiter itself.
But what it does is as soon as those images come down
and are transmitted back from Juno to Earth
and are decoded and at the Deep Space Network's telemetry into
and sent back to our computers here at JPL,
they pretty much go straight
up to the Internet, to the Mission Juno website,
where anybody can download them and process them into,
you know, taking creative approaches,
you know, the scientific approaches to really piece out,
you know,
all the different channels and all that,
all the all of the components
of the Juno cam data and make their own images
and post them back to the website.
Now, Rosalee, we have Peter on YouTube.
Who wants to know
what percentage of Jupiter's moons has Juno mapped?
How many has it observed?
Well, Juno has obtained
images from IO and Roper, also Ganymede,
Lambda and
and some of these images
filled in gaps that we didn't have
at sufficiently high resolution from
Galileo and
so they although they didn't get this much data,
as Galileo did, you know, they got, you know,
very, very useful data, particularly for mapping.
And we use the images to map
the geology of the surface and the different terrains.
So it's it's really been a gift
that did to the extent that mission was able to get
such images of the satellites and also other data
adjusting to microwave radiometer. And
I collaborate with the Jiram, an Italian instrument
that's a thermal infrared, the instrument.
And again, we got amazing data from IO.
So it's it's really been an amazing gift
that we
use Juno to look at the moons
in. So you mentioned Ganymede.
And so I have a great fantastic
I have a great follow up question for you.
Stephen Jackson on Facebook
wants to know, will there be
any additional observations of the largest moon, Ganymede?
And, you know, I believe
Nelson has a mission called JWST that will look into this.
Right.
I'll I'll let Dustin answer that question.
But I just want to say that
Jules is on the European Space Agency mission.
Nasser has instruments on it.
So there is a lot collaboration, but
it's actually an ISA mission and it is going to
go to the Jupiter system and eventually orbit Ganymede.
So it's going to really focus on studying Ganymede.
But we'll also get some images of eruption and IO
amazing.
Anything you'd add? Dustin
So Juno did a close encounter with Ganymede
into in 2021 in the summer, and we got really nice data
from that.
We won't be able to go back, unfortunately.
So we had the one shot at seeing Ganymede with Juno.
But as, as was mentioned, the European Space Agency
Juice mission, which there are NASA components on,
will be looking at Ganymede and very detailed.
And so I have one question to follow up on.
We have Idol s on YouTube.
Who wants to know where did these two moons, Europa
and IO get their names from Rosalee,
Well, those are names from Greek mythology.
In fact, Jupiter was the like
the king of the gods in Greek and then Roman mythology.
And, you know,
when he let's say that he was
in a bit of a philanderer, he wasn't faithful to his wife.
And his wife, in fact, was called Juno.
And so the moms are named
yeah, the moons are named after some of his lovers.
And the Emperor IO was a Nils Smith,
eventually got turned into a cow by Juno.
man, that is.
That is a fun fact. Thank you for that, Rosalie.
And so I wanted to get back to
the science of the two moons again.
We've got a lot of interest coming in for Europa,
and so we have a robust brain on X who asks,
Do we know what the planetary core is made of on Europa?
Dustin
So we believe Europa has
a solid core composed of what we call
its more rocky elements, what we might be more used to.
Is it the same as the center of our earth?
Maybe, but probably not.
And so that's one thing that the Europe
that the Europa Clipper mission will be doing
is mapping out the interior structure of Europa.
You know, how many layers are there,
how deep is the ocean, how deep is the ice crust
and how big is that the core of Europa
and why in spring on
X wants to know where did the ice come from on Europa?
Rosalie
Well, water
and ice are very common
elements in the solar system, so it really came from the
solar nebula, from the formation of the Jupiter system.
We think that those moons were formed
in the same part of the solar nampula as Jupiter,
but IO has no water, so they ended up very different.
That which is, which is interesting.
And the but again, if we look at our solar system,
the planets are all very different.
And so my next question is from Miss Lamb's classroom.
We've touched on this earlier,
but for those just tuning in, would
you would not be able to create a spacecraft or a machine
to check for life under the ice layer on Europa?
Dustin
Yes, that is certainly possible.
And that that could be a potential follow on mission
to the Europa Clipper mission, where we would design something
to land on the surface of Europa and take samples directly and,
and do what we call it in situ measurements of,
you know what then, then you can use,
you know, direct measurements of the ice
on potentially if you land in the right spot,
drill through and get
water samples and that would be very interesting
data in order to determine
habitability or life.
And so I have another follow up question from Aslan's class,
a great one for both of you.
What would you say is the most interesting data
or images that Juno has been able to collect?
Rosalie, we'll start with you
and then we'd love to hear your thoughts. Dustin
Well, of course I'm prejudiced.
I love you.
So I think that the the images of IO
were the most interesting that Juno ever collected
in terms of, you know, scientifically valuable.
You can argue that that Juno was a mission
to study Jupiter and the subway.
It found a lot of cool things about Jupiter itself.
So the moons are kind of like a
as I said before, the mission was not designed
to study the moons.
But I think that the images we got of IO,
not just the camera images, but the data from Jiram,
for example, has shown us that IO has a lot
more lava lakes than we knew off from Galileo.
And I'll let
Dustin give his opinion.
Yeah, so that's always going to be
an opinionated response to a question like that.
We're ready for it.
What's the most interesting data?
You know,
I would say we're all
a little biased in that way, so I'm going to actually choose
what we discovered on or what
with the gravity science of Jupiter,
which determined the interior of Jupiter.
And that's, you know, it was not what we expected at all.
There's we see that the zones and belts around
Jupiter penetrate very deeply into the surface.
It's not just right on the it's not just like a weather layer.
You know, these zones and belts, they penetrate 3000 kilometers
into the into the structure of of Jupiter.
My favorite image is actually
what was just shown there, which is the pole.
And we never would be able to really
look at the pole of Jupiter as Juno flew right over the pole.
And as soon as we got those pictures of over the pole
of, of of Jupiter, it's just astonishing.
You can see all of these cyclones or anti cyclones
just just visibly right there on the surface.
That's not something that you can see from Earth.
You have to go there and put a camera on the pole
in order to see it.
And that was just mind boggling to me when I saw that image.
And I have again, another
biased quick question for you both.
From over 101 enterprise on X, who wants to know
which one of the Galilean moons is your favorite?
Dustin, we'll start with you.
Rosalie I think we could guess that one.
Well, I'm going to have to go with Europa on this one.
You know, it's it's an ocean world that that we can access.
And we're planning a mission to it.
And there's going to be
so many interesting data that come out of that.
You know,
if it's a strong candidate for their potential to be life
and I just love looking at the surface of it.
It just looks
you know,
it looks so alien and foreign and you see all these cracks
and ridges.
And I that's my favorite.
And Rosalie, what about you?
Well, well, of course I'll is my favorite moon. And.
And, hey, it looks like a pizza.
In fact, it was nicknamed the pizza Man.
So if you like pizza, you, you like IO
and it's just for
volcanologists is absolutely heaven.
We we have so many volcanoes and so many we had formations
that you don't see anywhere else
in the solar system and the and a surface
that has no water and but a lot of sulfur dioxide.
So very different materials from what you see on the road.
But Ganymede and Callisto and the audience and the
and the house, there's some enormous plumes
up to 500 kilometers
that erupt from the surface.
So there is something exciting happening on IO all the time
that makes mapping it quite difficult
because you look at the IO with one spacecraft
and then it changes.
In fact, it changes in months.
We can have a big eruption that deposits
a lot of material on the surface and you think,
it doesn't look like you know, it used to.
So there is always something happening on IO.
Yes. Well, thank you both so much for joining us today.
Unfortunately, that is all the time that we have.
But again, we really appreciate you
taking so many questions from our viewers online.
Thank you for having me.
It's been such a pleasure to talk about it.
Thank you.
It's really been fun.
So, you know,
keep keep looking at the websites.
You'll know we'll do a lot more.
Thank you again.
And thank you to everyone who joined us online.
We hope you enjoyed learning more about
fascinating worlds of Europa and IO.
If you'd like to stay up to date
on the Juno mission and its study of Jupiter's
moons, visit go dot NASA.gov forward slash Juno,
or follow NASA's Solar System on Facebook, Instagram and X.
If you enjoyed today's show, you can check back with us
tomorrow, March eight, at 11 a.m. Eastern.
Dr. Lori Glaze, our head of planetary science at NASA
and U.S.
poet laureate Ada Lamo will be taking to the stage,
kicking off the South by Southwest festival.
Chatting about our Europa Clipper mission,
which is launching later this year
to see if Jupiter's icy moon has conditions suitable for life.
Visit Go dot NASA.gov.
Forward slash Europa Clipper x S.W.
to watch live and you can stay tuned for a special surprise.
Thank you all and see you next time.