Episode Transcript
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Okay, picture this.
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You're huddled with this group of scientists.
Yeah.
And you're staring at these grainy images.
They're being beamed back from the spacecraft
billions and billions of kilometers away.
And these images are of Pluto,
that little world that we once considered the ninth planet.
Yeah.
And you're expecting to see this cold,
dead cratered ball of ice.
Basically a cosmic fossil.
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But instead, what you see takes your breath away.
It's like Pluto is throwing this giant slushy party.
Welcome to Cosmos in a Pod,
the Space and Astronomy series.
Please like, comment, share and subscribe.
Today we're taking a deep dive
into the incredible discoveries
of the New Horizons mission.
This mission flew past Pluto in 2015.
And it completely changed our understanding
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of what this dwarf planet is all about.
Yeah, it's really a classic underdog story.
You know, Pluto gets demoted to a dwarf planet.
Everyone thinks it's gonna be boring.
And then bam, it turns out to be one of the most fascinating
and geologically active worlds
that we've ever seen in our solar system.
Exactly.
So set the scene for us.
What were we expecting to find
when New Horizons reached Pluto?
Well, back then Pluto was like the ultimate cosmic unknown.
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We had these fuzzy telescope images
and they hinted at a world of ice and rock,
probably heavily cratered from billions of years
of bombardment by asteroids and comets.
It was thought to be a relic of the early solar system,
phrasing in time.
A sort of celestial time capsule.
That's a great way to put it.
But as New Horizons got closer and closer,
the images got sharper and sharper.
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And scientists started noticing things
that just didn't fit with that old picture.
Like what kind of things?
Give us the highlights.
Well, for starters, there were mountains.
Not little bumps, but towering peaks.
Some of them over five kilometers high.
And I remember Pluto is smaller than our own moon.
Then there were these vast plains of nitrogen ice
and they looked incredibly smooth,
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almost like they'd been recently resurfaced.
But the real jaw dropper was the discovery
of what appeared to be giant volcanoes.
Volcanoes on Pluto.
But how is that even possible?
It's so far from the sun.
It should be frozen solid.
Yeah, that was everyone's reaction.
It just didn't make sense.
But there they were.
These massive structures that looked
for all the world like volcanoes,
but not the kind that erupt with molten rock.
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These are what we call cryovolcanoes.
Cryovolcanoes.
Sounds chilly.
What exactly does that mean?
Imagine a volcano erupting with this slushy mix
of water ice, ammonia, nitrogen, and maybe even methane.
That's a cryovolcano.
It's like Pluto's having this giant slushy party.
But instead of little paper cups,
we're talking about eruptions that can spew
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this icy mix for kilometers.
That's wild.
I mean, volcanoes on Earth are impressive enough,
but this is on another level entirely.
It's a completely different kind of volcanism,
driven by processes we're still trying to fully understand.
And it tells us that Pluto is far more geologically active
than anyone ever imagined.
OK, so we've got mountains, smooth plains,
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and these mind-boggling cryovolcanoes.
What else did New Horizons reveal
about this surprisingly lively little world?
One of the things that really blew scientists away
was the lack of craters in certain areas.
Now, you'd expect a world that's
been hanging out in the outer solar system
for billions of years to be absolutely
pockmarked with craters.
But some regions of Pluto's surface
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are incredibly smooth, almost completely free of craters.
So what does that tell us?
It means those surfaces are young, geologically speaking.
Something has been resurfacing Pluto,
erasing those impact craters, and creating fresh landscapes.
The prime suspect is cryovolcanoes.
Exactly.
Those icy eruptions could be acting
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like this cosmic resurfacing crew smoothing over the old
and laying down these new layers of icy material.
It's like finding a freshly paved road on a planet
billions of years old.
It means something is actively resurfacing Pluto.
It's almost like Pluto's trying to tell us, hey,
don't underestimate me.
I'm not just some boring dead world.
I've still got some tricks up my sleeve.
That's a great way to put it.
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And that's what makes Pluto so exciting.
It's forcing us to rethink our assumptions about what
it takes for a world to be geologically active.
All right, so Pluto is way more dynamic than we ever thought.
But here's the big question.
Where is all this energy coming from?
What's driving these cryovolcanoes
and resurfacing this little world
when it should be frozen solid?
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That's the million dollar question.
It's a mystery that has scientists scratching their heads
and coming up with all sorts of fascinating theories.
Well, let's unpack those theories.
What are the usual suspects when it comes to heat sources
for geological activity?
And why don't they seem to work for Pluto?
Typically, we think of things like radioactive decay,
where the breakdown of elements in a planet's core
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releases heat.
That's what drives most of the geological activity on Earth.
Another possibility is tidal heating,
where the gravitational tug of war between planets
and their moons generates heat.
We see this happening on some of the icy moons
of Jupiter and Saturn.
So those are the usual suspects.
But why don't they fit Pluto's profile?
Well, Pluto is just too small for radioactive decay
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to be generating enough heat to power all this activity.
And while it does have moons, they're
not big enough to generate significant tidal heating.
So we have to look beyond the usual suspects.
All right, so we need a new suspect.
What are scientists proposing?
What could be generating enough heat
to keep Pluto geologically active?
One of the most intriguing possibilities
is that Pluto has a hidden ocean beneath its icy surface.
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A hidden ocean, like the ones we suspect
exist on Europa and Enceladus.
But how could Pluto have enough internal heat
to maintain a liquid ocean when those other icy moons rely
on tidal forces?
That's precisely what makes Pluto so fascinating.
It's breaking the mold.
The leading theory is that Pluto formed
with a lot of internal heat.
And this heat, trapped beneath this thick layer of ice,
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could be enough to maintain a liquid water ocean.
It's basically leftover heat from the planet's formation,
slowly dissipating over billions of years.
OK, so Pluto might be harboring this vast hidden ocean,
kept warm by the dying embers of its formation.
That's a pretty mind-blowing concept.
But how does this hypothetical ocean
connect to the cryovolcanoes and the resurfacing
we've been talking about?
Imagine it this way.
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You've got this internal ocean that's
warmer than the surrounding ice.
This creates a temperature difference.
And heat always wants to move from warmer areas
to cooler areas.
So this heat from the ocean is slowly
working its way up through Pluto's icy shell.
And as this heat rises, it melts pockets of the icy material,
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creating the slushy mix that eventually erupts
onto the surface through the cryovolcanoes.
That's the idea.
And these eruptions would explain the smooth resurfaced
areas we see in the images from New Horizons.
It's a fascinating puzzle.
And we're still putting the pieces together.
And I have a feeling that's just the tip of the iceberg,
so to speak.
This hidden ocean raises even bigger questions, doesn't it?
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You're reading my mind.
Wherever we find water in the universe,
the question of life inevitably follows.
And that's where things get really interesting.
Exactly.
So we've got this potential hidden ocean on Pluto,
this world that's billions of kilometers away from the sun
and colder than anything we can imagine.
It seems almost counterintuitive to think
about life existing in such an extreme environment.
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You're right.
It's like something out of a science fiction novel.
But here's the thing.
Lice on Earth has shown us time and time again
that it can thrive in the most unexpected places.
Exactly.
We found organisms called extremophiles
living in scorching hot springs, deep sea hydrothermal vents
where sunlight never reaches, and even
in the frozen wastelands of Antarctica.
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If life can exist in those conditions,
who's to say it couldn't exist in a hypothetical subsurface
ocean on Pluto?
So maybe we need to broaden our definition
of what a habitable environment looks like.
Absolutely.
And that's one of the most profound implications
of the discoveries on Pluto.
It's challenging our preconceived notions
about where life might exist in the universe.
All right, so let's say hypothetically
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that there is life in this hidden ocean on Pluto.
What kind of life are we talking about?
Are we imagining little plutonium fish swimming around
down there?
Probably not fish if there is life on Pluto.
It's most likely going to be microbial life,
simple single-celled organisms that can
survive in extreme conditions.
Think of the extremophiles we find on Earth,
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those tiny, hearty creatures that
can withstand intense heat, cold pressure, and even
toxic chemicals.
So maybe not as exciting as alien mermaids,
but still a monumental discovery if we ever found them.
Absolutely.
Even the discovery of microbial life on Pluto
would be one of the most significant scientific findings
in human history.
It would tell us that life isn't a fluke, a one-off event
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that happened only on Earth.
It would mean that life has the potential to emerge and evolve
in environments that are vastly different from our own.
It would be a paradigm shift in our understanding
of the universe and our place in it.
Exactly.
And it would open up a whole new realm
of possibilities in our search for life beyond Earth.
OK, let's talk about how we might actually
go about searching for signs of life on Pluto.
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New Horizons was a flyby mission.
It gives an incredible glimpse of this dwarf planet,
but it wasn't designed to search for life.
That's right.
New Horizons gave us a tantalizing snapshot of Pluto.
But to truly search for signs of life
we need a dedicated mission.
So what kind of mission are we talking about?
Ideally, a mission that could orbit Pluto
for an extended period, allowing us
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to study its surface and atmosphere
in much greater detail.
We'd need instruments that could analyze
the composition of the surface and look
for any chemical signatures that might
hink at the presence of life.
Like what kind of chemical signatures?
We'd be looking for things like organic molecules,
the building blocks of life as we know it.
We might also look for imbalances
in the composition of the atmosphere,
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like an excess of certain gases that could be produced
by biological processes.
And what about those cryovolcanoes?
Could they offer any clues?
Absolutely.
Those eruptions could be bringing material
from that hidden ocean up to the surface,
where we might be able to detect it.
Pluto is giving us a free sample delivery service.
Talk about a cosmic gift.
So an orbiter would be a great start,
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but what about actually getting down to the surface
and exploring that hidden ocean directly?
That would be the ultimate goal, wouldn't it?
To send a lander to Pluto, maybe even one equipped
with a probe that could penetrate the icy shell
and explore the ocean directly.
It sounds incredibly challenging.
It would be one of the most ambitious space
missions ever attempted.
The distances are vast.
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The environment is incredibly harsh,
and the technology required is still being developed.
But the potential rewards would be immarable.
It would be like opening a window into an alien world,
a world that might harbor life as we've never seen it before.
It would be a truly historic moment, a testament
to human ingenuity and our insatiable curiosity.
OK, let's bring it back down to Earth for a moment.
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While we wait for these future missions to Pluto,
what can we do here and now to learn
more about the possibility of life on this distant world?
That's a great question.
We can continue to study extremophiles here on Earth,
those organisms that thrive in conditions that mimic what
we think might exist on Pluto.
By understanding how these organisms survive and adapt,
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we can gain insights into the potential for life
in those extreme environments.
It's like using Earth as a living laboratory
to help us understand other worlds.
Exactly.
We can also continue to develop new technologies
and instruments that will be needed for future missions
to Pluto.
And we can continue to analyze the data from New Horizons
looking for any clues that we might have missed.
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It's amazing to think that even though New Horizons is long
past Pluto, the data it collected
is still giving us new insights and fueling our curiosity.
It's a treasure trove of information,
and scientists will be pouring over it for years to come.
So Pluto has gone from being the demoted planet, the one we
thought was boring and lifeless, to being this incredible world
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full of surprises and potential.
It's a cosmic underdog story that's
captured the imagination of scientists and the public
alike.
And it's a reminder that there's still so much out there
to discover, so much we don't know about our own solar
system, let alone the vast universe beyond.
It makes you wonder what other secrets are lurking out there,
just waiting to be uncovered.
That's the beauty of exploration, isn't it?
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It's a journey into the unknown, and there's always
the possibility of stumbling upon something truly
astonishing.
I think we're ready to dive into some of those astonishing
possibilities, specifically the implications
of finding life on Pluto.
Let's do it.
This is where things get really exciting.
OK, so we've established that Pluto
is way more interesting than anyone gave it credit for,
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and that it might even have the ingredients for life.
Right.
Yeah, as we know it.
Yeah, and that brings us to what I
think is the most profound question of all,
what would it mean if we found evidence of life,
even microbial life, on a world like Pluto?
It's a question that's both exciting and a little bit
terrifying, isn't it?
Yeah.
It would completely change our understanding
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of our place in the universe.
Imagine the headlines.
Life found on Pluto.
Are we alone in the universe?
Everything we thought we knew is wrong.
It would be a global sensation.
People would lose their minds.
It would spark a whole new wave of interest
in space exploration and science in the very nature of life
itself.
Yeah, it would challenge our deeply held beliefs
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about what it means to be alive, about the conditions necessary
for life to even arise.
It would make us question whether life
is this rare and precious fluke, or whether it's
a fundamental property of the universe, something
that emerges wherever the conditions are even
remotely favorable.
It's like we've been looking for life
in all the wrong places, focused on finding planets
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that are just like Earth.
But maybe life is way more adaptable, way more resilient
than we ever imagined.
Precisely.
And if life can exist on Pluto, a world that's
so different from our own, then it
stands to reason that life could exist in countless other places
in the universe.
The universe could be teeming with life.
It's a mind boggling concept.
It really is.
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And it makes you wonder what other strange and wonderful
forms of life might be out there, what other secrets
are waiting to be uncovered.
It's enough to make your head spin.
But let's try to bring it back down to Earth for a moment.
What are the practical implications
of finding life on Pluto?
How would it change our approach to space exploration?
Well, for starters, it would make the search for life
a top priority for space agencies around the world.
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We'd be pouring resources into developing new technologies
and missions specifically designed to find and study
extraterrestrial life.
We'd probably see a whole new generation of scientists
and engineers inspired to pursue careers in space exploration.
Absolutely.
And the discovery of life on Pluto
would also have profound philosophical and ethical
implications.
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How so?
We'd have to start asking ourselves some tough questions.
Like, how do we interact with alien life?
What are our responsibilities to these newfound life forms?
Do we have the right to study them?
Or should we leave them undisturbed?
Those are some heavy questions.
It's like we'd be stepping onto a whole new ethical
landscape.
Exactly.
And it's a conversation we need to start having now.
Before we actually make those discoveries,
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we need to be prepared to grapple
with the implications of finding life beyond Earth.
Well, I think it's safe to say that Pluto has already
changed our perspective on the universe.
And it's only the beginning.
Who knows what other wonders await us as we
continue to explore the cosmos?
Pluto is a reminder that the universe is full of surprises.
It's a place where the impossible seems
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to be possible, where our imaginations are constantly
challenged, and where our sense of wonder
is constantly renewed.
Beautifully said.
And on that note, I think it's time
to wrap up our deep dive into Pluto's unexpected activity.
I hope you enjoyed this journey to the outer reaches
of our solar system.
It's been a pleasure exploring these mysteries with you.
Don't forget to follow Cosmos and a pod on your podcast
(15:32):
platform, and subscribe to our YouTube channel
for more deep dives into the mysteries of the universe.
Until next time, keep looking up.