Cosmic Queries – Volcanoes & Life in the Universe

Welcome to StarTalk, your place in the universe where science and pop culture collide.

StarTalk begins right now.

This is StarTalk, Neil deGrasse Tyson here, your personal astrophysicist, and this is going to be a Cosmic Queries edition.

I don’t know if you know the history of this.

We did it on a lark some years ago, because questions would show up in our inbox, and we said, why don’t we sort of staple them together and make an episode out of it?

And it turned out to be very successful.

Now you can only ask questions officially if you are a member of our Patreon network.

And so, but you can do that at the lowest entry level that we have, which is like $5 a month.

I got with me my co-host, Paul Mecurio.

Paul, how are you doing, man?

Hello, Neil.

Great to be back.

Yeah, I think $5 a month, everybody should be able to have $5.

You know, you should, unless you go into the track.

The track still exists.

Yeah, that’s $5.

That’s a cup of coffee at Starbucks.

I know.

That’s all.

For a month, right.

That’s all.

That’s all that is.

One less coffee.

That’s all.

Well, today we are orbiting the Solicited Cosmic Queries around the expertise of a friend and colleague from across the pond, Natalie Starkey.

Natalie, welcome back to StarTalk.

Oh, thanks for having me.

It’s always good to join you guys.

We love the accent.

We love the accent.

Oh my gosh.

We love it.

I can’t help it.

I don’t feel that sophisticated right now.

We just feel so inadequate.

I know exactly.

So let me remind people of Natalie’s expertise.

As I said, not only a friend of StarTalk, she’s an ace science communicator and she’s a science media producer at the Royal Society of Chemistry in Cambridge.

That would be Cambridge, England.

She’s written two books, Catching Stardust.

I love it.

And Fire and Ice.

And that has a paperback edition that’s coming out very soon.

And she wrote our Planetarium show here in New York City at the American Museum of Natural History.

And that show is called Worlds Beyond Earth.

I’ve seen that show.

And I remember saying to myself, there are flaws in this show that I wanted to talk to you about.

Hang on a second.

What did you mean when you said…

So this is the right moment for this.

I asked my wife.

I walked out.

I’m like, I cannot, I don’t know who wrote this.

Yeah, excellent.

And I love the two topics.

Remind us what Catching Stardust was about.

Was that the Stardust mission?

Well, it does feature within it, because I worked a little bit on the Stardust mission when I was doing lab work, but it focuses mostly on comets and asteroids just in general.

So I look at some of the missions that have been to comets and then talk about sort of the past, the history of comets and asteroids, and also then going to the future.

What are we doing with them in the future?

How are we going to divert them from colliding with Earth or how are we going to use them to mine them for precious metals and things?

Now, you realize there was a hit bestselling book and hit movie on exactly this subject, all right?

There’s been many books.

No, no, sorry, not just the collision part.

But I think Michael Crichton’s first novel was The Andromeda Strain.

I think it was where there’s a piece of sort of space dust that we captured and brought back to Earth because wasn’t the Stardust mission we brought comet dust back to Earth?

Yeah, so Stardust, yeah, that was the first sample return mission from a comet.

So as any good science fiction movie or story unfolds, we go into space and something bad happens.

So that’s the whole plot.

Well, it wouldn’t really be much of a movie to stay and watch.

It’s like, well, we went to space.

Everybody was very pleasant and they gave us tea.

And we analyzed the sample in the lab.

Let’s catch up with what’s in the lab.

So you didn’t bring back any killer bugs, I guess, unless that was COVID.

No, but they did bring back amino acids, which is really cool.

What a lot of people don’t realize is that comets and asteroids contain basically the building blocks for life.

And so actually they measured glycine, which is one of the amino acids, within the cometary samples that were collected by Stardust.

They didn’t know it at the time.

They were worried it was actually contamination that had been brought about from the scientists handling the material.

But then since then, we’ve analyzed other comets in space and samples of comets and we’ve seen it there again.

So we know that actually the stuff that was on the Stardust samples was amino acids in space, which is really cool when you’re thinking about life elsewhere in the solar system.

You said it just casually, but it’s a very big challenge to make sure that we don’t contaminate the samples that we’re analyzing.

Yeah.

And say, look, there’s DNA.

Hey, look, there’s the rhinovirus.

Hey, there’s, you know, oh, there are frogs.

Why don’t you have your gloves on?

How many times do I have to tell you this?

Here’s a box of Kleenex, you know.

Can you stop sneezing?

The dust is making me sneeze.

Yeah, so that’s a whole branch of NASA, I think.

Planetary protection, right?

Yeah.

They have a whole division called planetary protection, where we don’t forward contaminate where we’re going to explore, and we want to make sure contamination doesn’t come back to Earth.

Precisely.

So yeah, because if we send a spacecraft up into space and we want to land it on a planet or a moon or a comet or asteroid, we don’t want to then take bugs from Earth and then put them on that place and go, well, look, we found these bugs here.

We need to know that that’s perfectly clean before we do that.

So that’s why we don’t just go out and just put things on different planets and things.

That would be relatively easy to do, but we need to make sure that we’re protecting where we’re going.

And equally, the other way around, we need to make sure what we bring back doesn’t end up with Earth bugs on it and we don’t know where they’ve come from.

At the risk of a silly question, so the amino acids that were found, I know there are amino acids here because I hear about them.

Are they different than the amino acids that exist on Earth?

Great question.

Really good question.

Actually, there’s more amino acids in space than we have on Earth.

There’s more amino acids than we need for life as we know it.

So actually, now we’ve been analyzing loads of different meteorites, which is pieces of space rock that have landed on Earth and other samples from space.

We’ve discovered a whole raft of amino acids, way more than we need.

So it might be that they’re not all needed for life, but they just exist anyway.

Natalie, I think you’re taking the extra amino acids and making life forms of your own.

Well, maybe.

And that’s what we’re yet to find out.

But we know the potential is there.

So in any of these moons or comets or astros, maybe there are different forms of life that we don’t know at the moment.

So yeah, there’s so much out there.

Her neighbors are like, is it me or are there like six or seven more people in Natalie’s house than yesterday?

Yeah, and they’re like, there’s like an old man and a baby.

No, there’s someone trying to crawl out of the basement.

So how about, there’s another point here.

This is a little bit inside baseball, but Natalie, that’s an expression we use here in America when you’re about to give detail that probably no one cares about.

Because there’s a TV show called Inside Baseball and you really have to be into baseball to just watch it or come near it at all.

So this is an inside baseball question.

As I remember my biology, life on Earth has a handedness to it.

Not that you’re right handed or left handed, but the molecules twist in a way that they could twist the other way, but they don’t.

And if they did, we couldn’t use it in our life forms anyway.

So on these rocks or in the comet dust, do you have both, do you have half twisting left and half twisting right?

So this is the chirality, isn’t it?

And you know what, this is so bad, but I can’t remember what they found.

So basically, if you found it, are we left, aren’t we, on Earth?

Here’s my definite answer.

We’re either left or right chirality, I’m sure of it.

I can’t remember.

And I don’t know whether it’s really important that if we had the other handedness, whether we couldn’t have a parallel life in that handedness or not.

But honestly, my brain has gone blank not having looked at this.

It’s my understanding that we could, but we just don’t.

It’s just an observed fact.

Yeah, that everything is in one way.

And my understanding, Paul, do you remember that, was it a potato chip or something that Frito-Lay made where it had all the oil of any normal chips, but you couldn’t digest it?

Because I think the molecule had a different chirality to it.

It went through you, yes.

And the warning on the back of the packet said, may cause anal leakage.

Because your body has no idea what to do with it, even though it’s oil.

Well, thank God we’re talking about something I know now, anal leakage.

So let me tell you, when I was a young lad…

So I think there’s a whole fascinating sci-fi story waiting to be written about whether you have left-handed or right-handed chirality in a life form.

Because that means you could eat them, but it wouldn’t be nourishing to you.

Right.

Okay, so you could find lettuce somewhere, but you’d be like, this is lettuce, it’s no good to me.

But yeah, no, I think that’s another issue we have that we would need to develop experiments to put out in space to actually be able to measure that.

So it’s one step actually measuring whether you have amino acids, and then it’s another step figuring out more information about them.

And we’re sort of in the first steps when we’re going out to look at planets and things.

And I have a fast chirality story, I’m pretty sure this is true, that the molecular form of the flavor for mint, okay, I think it’s spearmint, is the molecular form is identical to caraway, except caraway has the opposite handedness.

And so when it intersects your taste buds, your taste buds respond differently because of the different handedness of them.

So mint and caraway are chemically identical, which is really cool.

Yeah.

Well, let’s get to some Q&A.

So Paul, what do you have for us?

Did you collect these?

I collected them myself.

I went through them.

And there’s some really great questions.

And we’re going to start with Christopher Stowe in Pennsylvania.

Is there a relationship between active geology volcanism and a planet or moon having a magnetic field?

Oh, yeah, that’s a great question.

So generally, we think yes.

OK, so we think that a body has to be active and activity means that you need to have heat within that body.

And that can create basically liquid.

So we need a hot, rocky core usually.

And that could create a liquid ocean underneath an icy crust, like we see through many moons throughout the solar system.

We need that kind of activity and the movement of material.

It doesn’t have to be rock and water.

It can be other elements.

And we think that needs to actually be there to create a magnetic field.

So we have seen magnetic fields all throughout the solar system, but they’re not that common.

They’re common on some of the bigger planets.

And I think just a couple of moons we’ve detected these kind of magnetic fields.

But you can’t just have liquid.

I mean, it has to be conductive, right?

Yes.

So a salty water can definitely do that, a salty ocean.

So you’re saying it’s not just that you have, it’s not just that the place is hot, is that there’s a difference in temperature between places within the object so that things can vect and move, right?

Yeah.

Yeah.

So it’s not necessarily boiling hot, it’s just warm enough that you’ve insulated a crust and then you can keep something warm enough that it’s liquid and it can move so there’s heat below and things move around.

And when it comes to cryovolcanism, doesn’t it have to be a mantle below this?

There has to be.

So in other words, for that liquid to be able to not freeze so that even though you’re on a super cold atmosphere.

Yeah.

Listen to Paul showing off he knows what cryovolcanism is.

Listen to him.

I looked up one word and I repeated it like a hundred times.

He sounds so knowledgeable.

My man does his homework.

Yeah, so cryovolcanism, generally it’s happening in places that are icy because we’re talking about cryobing, the ice part, and the volcanism is the movement of that material.

So usually underneath an icy crust, you’ve got a rocky core in the middle which is warm and then this kind of salty liquid ocean and it’s from there that you’re pushing material out.

So it’s that mantle, as you call it, on Earth.

Our mantle is made of rock and it’s below a rocky crust.

But on these kind of icy moons, the mantle is made of water or methane or ammonia or some other solvent and that becomes your mantle, but it’s just made of something different.

I like that analogy because you’re analogizing basically the physics of what it’s doing rather than the properties of the material itself.

I love that.

And then there was the pulls of the moons that allow the movement of that subterranean water so that it doesn’t turn to solid as well, right?

There’s a sort of movement that happens?

That happens in moons around these giant planets like Jupiter and Saturn.

They wouldn’t just be hot if they were not next to that big planet.

They need to be pulled by the gravity of that planet as they go about their orbit.

And it’s that rocky interior that’s pulled and pushed and squeezed, and the rock is grinding all against other bits of rock, and it by friction heats up, and then it creates that heat that makes that mantle liquid and then produces that activity.

So, you know, if Io, for example, wasn’t next to Jupiter, it wouldn’t be the most volcanically active object in the solar system.

But I think what Paul was referencing was if it was only Io and only Jupiter, then it would stabilize into just a tidally locked orbit, and then there’d be no heat drivers.

But we have other tugging forces that, like you said, it’s a push and a pull and a tug, and everybody’s trying to get a piece of the action, and the response to that is a deposition of heat.

Yeah.

All right, Paul, give me one more before I break.

See if we can squeeze it in.

This is Connor Holm.

Firstly, I loved fire and ice.

You really make geology exciting.

Oh, that’s so good.

I like the way that sounds.

It’s like, we know it’s not exciting.

We need it, Natalie.

Well, that is one of the problems.

People think geology is really boring, and then they look back.

No, Natalie, that is the highest compliment.

Yeah, absolutely.

In a typical volcano, how high is the pressure buildup and how is it measured?

Does this vary between Earth and space volcanoes?

I like that, but let’s take a quick break.

So we’re going to take a quick break.

When we come back, more with our solar system expert, Natalie Starkey, when StarTalk returns.

Hi, I’m Chris Cohen from Haworth, New Jersey, and I support StarTalk on Patreon.

Please enjoy this episode of StarTalk Radio with your and my favorite personal astrophysicist, Neil deGrasse Tyson.

We’re back to StarTalk Cosmic Queries.

My co-host, Paul Mecurio.

Paul, always good to have you, man.

All right, and friend of StarTalk, solar system expert, Natalie Starkey, coming in from the UK.

Natalie, great to see you again.

Yeah, good to be back.

Always good to have you.

Very good to have you.

Paul, we dangled a question there, something about what’s the difference in the pressures between like earth volcanoes and space volcanoes?

And that’s an interesting fact, and how is it measured?

So Natalie, how should we think about the undercrust pressures that ultimately just blow a gasket?

Yeah, so actually it’s really dependent on the volcano you’re looking at, even on earth, you get loads of different conditions.

So you’ve got some volcanoes that will erupt at lower pressures and some that erupt at higher pressures.

So generally what we’re looking at is the amount of gas that’s contained within the magma.

And if you go to, for example, let’s take Mount St.

Helens, everyone’s heard of that big volcanic eruption that exploded half the National Forest.

That had a lot of gas in the eruption and it was there for a higher pressure.

If you go to somewhere like Hawaii, you’re looking at Kilauea, that’s at lower pressure.

It’s got less dissolved gas within the magma.

What happens is as that magma rises with all those dissolved gases, they start to expand as just the pressure of the crust decreases and that magma gets thrown apart basically.

So that’s what would create a very explosive eruption, but you’ve always got dissolved gases.

So even in Kilauea where it’s not very explosive, you’re gonna get quite high pressures.

So it varies a lot.

Now, when we go into space, you’re basically then it’s very dependent on the individual place that you’ve got.

If you’ve got a smaller body or a big large planet, we tend to only see activity on the smaller bodies.

So we’ve seen them on Mars and we’ve seen quite big volcanoes on Mars and we’ve got loads of volcanoes on Venus which are actually still active today.

We’ve recently discovered that there’s still activity today there.

Which ones on Mars are dormant, obviously, or dead.

Yeah, Mars is dead.

So we haven’t seen activity on Mars for quite a while now, billions of years, I think.

It’s possible that it could one day have another eruption.

It’s very, very unlikely.

But Venus, on the other hand, is continually erupting.

So it’s really, really active, probably much more active than Earth.

And those individual volcanoes again, are going to be all at different pressures and it will just be at a point when it will erupt.

But they’re probably more similar to what we see in Hawaii, those volcanoes.

Okay, so I have a task for Paul.

Paul, I want you to invent…

You know how we tap a keg?

We should figure out a way to tap a volcano.

So we can release the pressure so that it doesn’t blow its head, okay?

And level cities that are at their base.

And that’s the thing with super volcanoes, if they can release a little bit of pressure along the way with a little eruption, then it takes the pressure off that big one happening.

So when they say, oh, there’s a Yellowstone eruption due, it’s due, but it has little eruptions and releases bits of pressure along the way.

So it just kind of extends that timeline to when that big one’s going to happen.

Maybe that big one never happens because it just along the way releases the pressure.

We should purposefully dig holes and let some pressure.

Let me ask you something.

How much greater is the pressure than the baking soda volcano I made in fourth grade?

Because that sucker spewed everywhere.

And I got to tell you, it ruined my mother’s drapes.

I was grounded for a week, literally.

I can’t believe you did that indoors.

I did it outside in the garden on the grass and it killed the grass.

And I was in loads of trouble as well, so, yeah.

A quick question, in all seriousness.

Is there a common reason when volcanoes go dormant in space, is there a common, is research showing a common reason for that?

Or does it vary depending on the celestial body and other factors?

Wait, wait, Paul, are you a Patreon member?

Hang on a second.

I got $5 somewhere.

You got $5?

Go find a $5.

All right, we’ll go, we’ll ask the next question.

Put it in the piggy bank, okay.

Next question, are we moving on?

Yeah, no, you can ask your question, Paul.

I think you…

I forget it now.

You ruined it.

I ruined the moment, okay.

No, no, no, go ahead.

I think it’s a good question.

So basically, in order for a body to be active in space, it’s got to be warm.

We spoke about that in the last segment.

We were talking about how we’ve got to have heat within a body to create activity, create movement of material within that body, whether it be rock or methane or water, whatever it is that becomes that magma and lava on that particular body.

So if that particular object cools down, it loses its heat for some reason, it’s just primordial heat.

A lot of bodies were just active because they had heat from formation because they formed from big kinetic impacts in space and that created heat.

They just lose that over time and they die.

All the volcanic activity dies off and they can no longer be active because they’re not warm enough.

But then we go somewhere like Jupiter where we’ve got this push and pull of the gravitational energy.

Those bodies can be active forever really because if they stay where they are and Jupiter keeps going around the sun, then they’re going to keep being active.

So there’s really no time limit on that.

So can we say that Mars has just simply cooled off from its formation and is smaller than Earth, it would cool faster.

And so now it’s got no action left.

Exactly.

And the same with the moon.

It’s even smaller.

So it just cooled off quicker.

So Earth is sort of this really nice example.

It’s not too big that it became ridiculously size like Jupiter or something and it’s just not even a rocky planet any longer.

It’s just big enough to have kept its primordial heat and it also generates its own heat.

So it’s kind of that really nice sweet spot of being able to be active but not be too active.

It’s not too hot.

It’s not too cold.

So it’s kind of, you know, the perfect planet, I think, anyway.

So Paul says the geologist we’re in a sweet spot that gives us volcanoes, earthquakes and tsunamis.

Thank you, Natalie.

Paul, you got a sweet spot.

Right, right.

Imagine being at her house, hey, there’s going to be a hurricane this weekend.

I can’t wait.

The sweet spot.

Okay, moving on.

Moving on, we got Troy from Virginia, what are the current processes of detecting life outside of Earth?

Would it be detecting radiation around an area that could contain food for different life forms, or is it something else?

Oh, that’s really cool.

I love this topic.

So one of the ways that we first go out into the solar system to look for life is not to look for life itself.

It’s to look for the environments that could host life.

So we want to look for habitable environments.

Now, we think that includes liquid water because we think from what we know about Earth, all the environments we find life and where we think life started included liquid water and heat.

So we go out to all these places and this is why we’re sending the JUICE mission, which launched just recently.

It’s looking at some moons around Jupiter that have those environments.

They’ve got warm interiors, they’ve got liquid water, and these create what we call hydrothermal systems, which is what exists at the bottom of our oceans.

And we think life actually started on Earth, potentially, at the bottom of our oceans, where the heat is emanating from the Earth, and it’s interacting with salty liquid water and creating nice environments for microbes to thrive.

So that’s where we’re going.

We’re going to look for these environments and then we’re going to go, okay, do these places host the right ingredients for life?

And then we will look for life, because there’s no point living for life.

It’s really hard to see life, because if it’s microbial, for example, we’re not going to be able to see that from orbit.

We’re going to have to land on that planet, we’re going to have to drill in, we’re going to have to delve into an ocean to actually see microbes.

Drill, baby, drill.

That’s complicated.

Of course, if there’s dinosaurs roaming on these places, we’d see that from orbit, fine, but we don’t expect to have dinosaurs roaming around.

So we’re looking for very probably small life, or it might have been life that doesn’t, it’s now died off.

So we’d be looking for fossilized microbes, which is incredibly hard to find.

So initially, we’re just going to look for environments.

Like we’ve been doing on Mars, we’re looking for those kind of saline, watery environments that might have hosted life in the past.

And that’s the best place to start.

You don’t expect to see fossilized microbes because they don’t have bones and teeth, right?

It’s a speck of dust.

In the geological record, we have seen examples of where sometimes stuff without, or bones and everything has been preserved, but it’s incredibly, it’s really uncommon.

You’ve got to have perfect conditions of deposition to kind of cover that stuff over and preserve it perfectly in that record.

So it’s not destroyed over time, right?

Yeah, exactly.

I mean, you would need to be on the surface of a planet to find that, and you’d probably want humans there to be looking robots and, you know, they’re going to go and do a good job, but you need, you know, humans that are in superior intelligence to help find these things.

Until AI becomes our overlord, then they’re our security.

Which is about a week away.

Why don’t we just set out next week, you know something, Paul.

It’s happening.

That’s what I was told by my AI.

Why don’t we just set out some like alien bait, like a full spectrum radiation banquet.

Like, it’s almost like a banquet on a carnival cruise where just people eat so much, they fall asleep in their chair.

So the aliens come, they eat the radiation banquet, they fall asleep and then we trap them and then we study them.

I mean, we do send radio signals out into space.

So this is assuming that aliens can detect our radio signals and understand what we’re saying, but we have been doing that and we’ve sent messages out on spacecraft over time to go out there and just say, look, we’re here.

I don’t know, we’re not sure if that’s a good idea because we don’t know if these aliens are friendly or not.

In retrospect, that feels a little dangerous, but yeah.

Yeah, but yeah, we do that and another way, so when we’re talking about the solar system, it’s one thing because we can get to these environments, we can send spacecraft and investigate them, but you then get to the exoplanet.

So these are all the objects around other stars, other star systems so far away, we can’t directly see them.

So we’re using a different type of science then to try and detect what might be going on.

Initially, we’re just looking for whether the planet is hot or cold and how close it is to its star because if it’s too far away, we don’t think it would be able to host life.

Is it too close?

It will be too hot.

So we’re looking for things that are kind of within a zone that might be able to host liquid water or definitely have activity.

But that’s like the next step.

A Goldilocks zone.

The Goldilocks zone is sort of being a little bit disproven more recently because we’re starting to now in our solar system see environments way away, like Pluto, for example, not in the Goldilocks zone, but it’s geologically active.

And there is every chance that life could have started there because it’s got all kind of the right conditions for very weird life to exist, but it could be there.

A new species of dog, yeah.

It’s a species of dog that cleans up after itself.

So Natalie, you mentioned, you just slipped by, you mentioned it, we did an entire explainer on it, but just for those, this might be their first time hearing, use the word juice mission.

Could you just spend just a minute on that before we go to the next question?

Yeah, so the juice mission just launched recently.

It’s a European space agency mission.

And okay, so the acronym is really forced.

It’s Jupiter, IC Moons Explorer.

So you kind of have to think through that one for how they got juice out of it.

But it does work in some way.

All the letters are there within those words anyway.

Yeah, J-U Jupiter and I-C Ice and E Explorer.

That’s not too forced.

Okay, it’s not too forced.

But yeah, it’s not going to be arriving at the Jupiter system until 2031.

So I think this is one of these crazy things about space missions.

They set out and then it takes forever to get anywhere in space.

It’s got to do some slingshots of Earth and gain gravitational energy to get out to Jupiter.

But it’s then going to be looking at Europa, Ganymede and Callisto, which are three of Jupiter’s moons.

And actually NASA are going to launch, hopefully launch the Europa Clipper mission next year, I believe, which is actually going to then get…

It’s getting there ahead of J-U, which is a bit cheeky.

It’s like going to arrive a year ahead, even though it launches later.

Natalie, everything’s not a competition.

We’re sorry about 1776.

You got to let it go.

Drop it.

Oh, my God.

I’m sorry.

Just to clarify, if you do not launch with sufficient energy to go straight there, then you need the gravity assist through some, you know, high-cushion pull shot in the solar system.

So it sounds from what you said that our Clipper mission from NASA will be on a larger rocket and it will be able to go straight there and not have to rely on gravity assist, which eats time in the duration to the destination.

Exactly.

And it’s also with the, you know, orbital dynamics.

It depends where the planets are when everything launches and then how far it is going to be to get to places and whether you can go in a straight line.

Is the focus of the…

I would imagine the focus of the two missions different, right?

It’s really, really similar, which is really cool because they’ll be complementary.

So, Europa Clipper is only looking at Europa, but it’s investigating the signs for life.

And then the G-submission is looking at all of those moons, investigating what their surfaces, what the composition is, getting more information in detail, just imaging surfaces.

We haven’t got hugely detailed images of these places.

And then measuring things like particles that are coming off of the surfaces, discovering what’s underneath in their liquid oceans, because they all have liquid oceans.

I think they all have more liquid water than we do have on Earth.

That’s my understanding.

That’s correct.

The total liquid content versus our oceans, right?

I think they have more.

Is it Iowa that has, Iowa has a hundred mile deep ocean or something like it?

That’s probably Europa.

Europa is the really hot one.

So that’s the weird one.

All the others I see there.

But yeah, so they’ve got huge oceans.

I think it might be Ganymede that’s the biggest one.

And it’s actually bigger than Mercury.

Yeah, Ganymede, right.

I understand that James Cameron is going to Europa to see if there’s anything that’s at the bottom of the ocean that he can somehow make a movie out of.

So that should be really good.

I’d watch it.

But I’d want to start a movement.

Any life forms we find on Europa, we should call them Europeans.

That’s perfect.

That’s how we got to do that.

Well, we have an explainer on that where if people want to do a deep dive on it, you can look it up on our website.

So Paul, give me one more before I break.

You got it right here.

This is Ian Diaz from North Florida.

Is it possible to get energy from a planet’s core?

And if it isn’t possible, how could we hypothetically achieve energy from a planet’s core?

I love that.

And let’s do take that break.

When we come back, we’re going to find out what is the future of geoengineering and how much energy does Earth have to give, especially relative to other sources such as oil or perhaps even the sun, when StarTalk continues.

Bye We’re back for the third and final segment of Cosmic Queries StarTalk.

I got Paul Mecurio with me as my co-host, and Natalie Starkey.

Natalie has two books under her belt.

We’ve done shows on each of those two books.

You can get them out of our archives.

One of them is called Catching Stardust, the study of particles brought back to Earth from space, and just dust everywhere where it matters when we think about life.

And my favorite of those two, sorry to pick one of your children here, Natalie, Fire and Ice, it’s got a way cooler title, I think.

I was going to say, can I just say, we need to make that a musical.

Fire and Ice the musical.

And then we have a volcano in Neil, like with Nathan Lane, he comes singing and dancing out of the volcano.

You need Nathan Lane if it’s going to be one of these.

And Fire and Ice will be coming out in paperback soon, because that’s the more recent of the two books.

We look forward to that.

And Paul, at the top, I forgot to tell people, you’re a comedian on The Late Show with Stephen Colbert.

Do you help write his jokes, like how does he work?

I basically perform on the show.

He and I go back to The Daily Show together.

I was a writer on The Daily Show, I worked on The Colbert Report, and I do a mix of things on The Late Show.

I think that’s when we first met, when I was a guest.

That’s where we met.

Yeah, guest on The Colbert Report, yeah.

I didn’t know you were in the green room, and I came in and tried to steal some of your snacks, and you caught me.

That’s not gonna happen.

And yeah, and I have a podcast called Inside Out, which you’ve been on, and Paul McCartney, and Stephen Colbert, and a whole bunch of cool people, so yeah.

Okay, so just to be clear, the title of your podcast is Inside Out with Paul McCurio.

Yes, it is, yeah.

Yeah, I should put my own name in there.

Probably would help, right?

That’s what it is.

Okay, you got it.

All right, so let’s pick up where we left off.

Okay.

We dangled a question, and please remind us of what that question was.

Is it possible to get energy from a planet’s core and if it’s not, how could we hypothetically do that?

Plus Natalie, if the core is really, really hot, then there are surely places between the surface and the core that are not as hot, where you don’t have to dig as deep and you could in principle still get energy from it.

Isn’t that right?

Yeah, so I mean, the core of the planet is incredibly hot.

I think it might be hotter than the surface of the sun.

Most of this heat in our core is leftover from four and a half billion years ago when the planet formed.

You’ve got all those impacts happening in space that built up the planets.

And that kinetic energy was turned into heat, which was stored within that metal core.

So you’ve got a lot of what we call primordial heat in there.

But then you’ve got this mantle of rock that sits around that.

And actually that generates heat all the time because we’ve got lots of radioactive elements sitting within the rock that decay over time and release little bits of heat, which when you’ve got a huge amount of rock that does that, creates a huge amount of heat for our planet.

So we’ve got that initial heat and then we’ve got the heat we’re always making.

And that’s about 50-50 in terms of the heat that our planet gives out.

Now, because of physics, heat always wants to move from somewhere hot to somewhere cold, which is space.

So it moves from the inside out and it keeps our planet active.

It creates volcanoes and earthquakes, but it also gives us our liquid water and it can create energy for us.

So, if we go to somewhere like Iceland, they actually just use all their electricity comes from geothermal energy and they actually heat their roads using just the heat from the earth because it’s very cold in Iceland and they have very icy roads.

So they just heat them because they’ve got all this excess energy which they don’t have to generate.

That’s the most badass thing I’ve ever read about.

It’s awesome.

So they don’t have snow shovels or they don’t have to salt the road.

They just heat the road.

Well, they do in some places, but particularly in Reykjavik because it’s quite, it’s not a huge population in Iceland, but a lot of people do live in the capital city and they can just do that.

They have all this excess heat, so they can just heat it.

Yeah, they’re just show-offs there.

They’re just showing off.

No, but an interesting point is that they used to be run on fossil fuels and they just made a determined effort for this shift.

It’s one of the more brilliant sort of scientifically literate energy stories in the world.

Yeah, and they can do that because they’re a volcanically active place.

They sit on the Mid-Atlantic Ridge, but they also have a hotspot underneath Iceland, which is just this kind of warmer area of the mantle that produces excess heat and excess volcanoes.

You’ve got the same in Hawaii, it’s a hotspot volcano.

But you don’t need to be near a plate boundary where you create volcanoes or near a hotspot to necessarily create geothermal energy.

You actually just need to drill down, not even very deep.

If you drill down a kilometer, you get a 25 degree increase in temperatures.

Now, you don’t even need that much increase to generate a little bit of heat.

I don’t know in the US if you have like air-sourced heat pumps for your houses.

We have, they’re quite common here now.

We don’t even know what that is, I’ve never heard of it.

I have one, I actually have one.

You’re a lion.

No, I will show you a picture right now.

It works at 30, listen to me, I know something about science here, focus.

At 35 degrees or above, this is a heat pump, so I don’t use so much oil in my furnace.

And if it’s 35 degrees or above, there’s enough moisture in the air, it’s a reverse process.

So it’s an air conditioning condenser that reverses its process.

It takes from the cold, the moisture goes through and it turns it into heat.

I am done, I finally said something that I know what I’m talking about.

So yeah, you don’t need a huge amount of heat.

We have saved a ton of money, in all seriousness, on our house, we’ve saved a ton of money on oil with this heat pump.

It’s becoming very common in the UK that we’re actually switching over to these and all new build houses.

Anyway, that’s kind of a tangent, but basically we don’t need a ton of heat to actually create enough to heat houses, heat hot water.

In other words, you don’t need to dig to the core of a planet to gain access to the energy that remains within the planet itself.

Yeah, exactly.

So we need to do that more.

If we want to do that, it is environmentally, we’ve got to question it a little bit because we’ve got to dig into our planet and we’ve got to lay pipes, but then we wouldn’t require fossil fuels, which would be great.

But yeah, it’s just one form of renewable energy, which we’re not really using, but Iceland have done it great.

I think areas of New Zealand do it because they have a nice high heat flow as well.

But yeah, definitely we take heat from our planet all the time.

Very cool.

Why don’t we harness the energy that we’re spending to get to the center of a salted caramel core pint of Ben & Jerry’s ice cream?

Because when you’re working toward that core, you can really harness that energy.

We’ll get top people working on that, Paul.

Another question?

All right, drilling, this is from William.

Drilling down to Lake Vostok in Antarctica has been cited as an analog for exploring ice moons like Europa.

Can you tell us what was learned from Vostok?

I love that.

So what is Lake Vostok, Natalie?

So the really cool thing about these environments on earth, like Lake Vostok and there’s some other areas in Antarctica we can look at is that you’ve got these bodies of water that have remained sort of pristine since they formed.

They’ve been capped off with ice and you’ve got this water that’s just stayed there the same and hasn’t had any human interactions in all the years it’s been there.

And this is very similar to the places we look at like Europa or Ganymede or anywhere else where we’ve got these liquid oceans with this ice capping it.

Not only just no human interaction, nothing has reached it.

Nothing has reached it, exactly.

No other part of the biosphere has touched it, right?

So these have been like, so if something’s gonna happen, it’s all up to itself, right?

Exactly.

Isn’t it like 16 million years ago, it was believed to have been sealed off like that long ago or even longer?

Certainly on an evolutionary time scale.

I don’t remember exactly how long these have been capped off, but the only point of this is it’s like an analog, right?

Is that what would you say?

Yeah, so we need analogs because it’s incredibly hard to go out and actually investigate these places in space.

We spoke about that already in this episode.

We gotta send spacecraft, it’s expensive.

It takes years to get these missions out there and plan them.

So actually if we can look at a similar environment on our own planet and compare it with those environments we think exist in space, then we can do a lot of the work before we even have to go out there and investigate what’s there.

So they become like a little comparative planetology experiment and it just gives scientists a really easy way to do their work, although it’s still relatively hard to get to Antarctica.

But we can actually do that science before we go to Europa and we can make all the mistakes here and then figure out what we need to do in space with very limited equipment.

Have they found weird life forms?

What do we know?

So what we know about, so we find lots of strange environments on Earth.

Some of the strangest environments are at the bottom of our oceans, where you find organisms living that just shouldn’t be able to survive.

There’s no light.

It’s incredibly dark and high pressures, very cold.

And these kinds of environments are where we find microbes that we call extremophiles.

They like extreme environments.

So humans and other animals that we see on the surface of the Earth couldn’t survive down there, but there are organisms that have adapted to those environments and thrive.

There’s a whole, you know, a whole colony of animals and bugs and things down there, which we just weren’t expecting to find.

So gone is this concept, this Darwinian concept of the room temperature tide pool, where that’s where you need the light.

I mean, it blows it completely open.

Yeah, in fact, life probably, we think, most likely started in one of these very extreme environments.

And so we’ve kind of developed to now think that we live in a very, you know, we can’t stand extreme temperatures.

We humans are a bit rubbish in that respect.

So Paul, did you just call us wimp ass creatures?

I think she did.

You know, I did not shave for this.

I don’t, you know, I, can I just ask, you talked about Lake Vosk being an analog, but isn’t it limited in some ways because you can only extrapolate so much because the host bodies are different, right?

Earth is a different celestial body than say Europa.

So there’s only so much you can glean from that analog.

And that’s like, with any science we do, we have to start with a set of assumptions and we always know there’s gonna be, you know, limits to the experiment.

And that would be one of the limits.

It’s not the same place, but it’s pretty close.

And in some respects, it’s close enough that we can test out some of these theories before we go out into space.

Hey, we don’t do close enough in America, okay?

We do it right, or we don’t do it at all.

There you go.

Do you want to go to another one more question?

We got time, a couple more, yeah, let’s do it.

Okay, this is Chase.

Greetings, Dr.

Tyson and Dr.

Starkey.

Chase from Indianapolis here.

My question is, could you pump as much water in the ocean as is to be added per year by the melting ice and then put it in a rocket and ship it to Mars?

Oh, so that we don’t have, so that in the climate change, we don’t flood the coastal cities.

Thus saving coastal cities and accelerating Mars projects.

Wow, because I bet the cost of picking up cities and moving them inland 50 miles is probably more than shipping water to Mars.

Can we just over, we’re overthinking it.

Can we just get 500 million jugs of Poland Spring delivered to another planet?

Probably get it in bulk, discount at Costco.

You create, you brilliant scientists, you’re always overthinking things.

Yeah, that’s true, that’s true.

Just ship it all out.

So was there a question in there?

What was the question?

Yeah, my question.

Could you pump as much water in the ocean as is to be added per year by the melting ice and then put it on a rocket and ship it to Mars?

So I think the first part of that question, I have no idea.

But the second part is gonna be the main issue, I think.

I’m sure someone who pumps water might understand the first part a bit more, but the second part is gonna be an issue anyway, because to launch bulk into space is the most expensive thing.

So this is why when we design space missions, we make everything very small and light.

The instruments we send usually are not very large.

Some of them are literally the size of a shoebox.

Obviously some spacecraft are much larger, but they’re made to be light, because it’s just very expensive.

The more rocket fuel you’ll need to launch some mass into space, the more rocket fuel you’ll need, because you’ve got then more rocket fuel, and it just is exponential.

So you wanna keep everything light.

So launching water into space is never gonna be a good idea.

We have to do it, but actually we limit it.

So on the International Space Station, they recycle their urine because they don’t have an unlimited supply of water.

If we go to the moon and Mars, like we’re planning to send humans out and create bases out there, they’re gonna need to find ways to generate their own water, either from rocks on the surface of the planet and the dust, or from a passing comet or asteroid, we might mine it for water.

That’s actually gonna be much more efficient than trying to launch the stuff off our own planet.

So that is a massive problem.

So, Paul, I think the answer is no.

Sorry, Chase, that’s a big no, buddy.

That’s a total no.

And last I heard the cost to launch a pound of anything in a payload is somewhere between $5,000 and $10,000.

So the rate at which the ice is melting per pound times $10,000, you know, that’s just, it would be prohibitive.

So let’s do that calculation.

What did it cost Bezos to launch William Shatner?

Let’s get the calculator out on that.

Do we, you want to do another question?

Yeah, yeah, let’s keep it coming.

Okay, this is Kayla Hunter.

Hey guys, what would happen if a volcano erupted on the moon where the gravity is at 0.16 G?

Would the lava float in the air or up and out into space?

So let me sharpen that question.

So the thrust of ejections from volcanoes, might they be fast enough to achieve escape velocity for the moon?

Or will it just be like a volcano in slow motion where things go up and fall down slowly?

So yeah, it can definitely happen.

We see on Enceladus, its volcanoes throw out material in plumes and some of that material ends up making Saturn’s E-Ring.

So one of the rings, I think, is the second one in that goes around Saturn.

The material for that ring comes from Enceladus’ volcanoes.

So it did achieve escape velocity?

Now, on the moon, we’ve had loads of volcanoes about three billion years ago, they all sort of stopped.

Now we had, usually, they were quite basaltic in composition.

So this is the same kind of volcanoes as we get in Iceland and Hawaii.

Very flowy, they’re not very viscous.

So they don’t have a lot of energy to explode out.

They just kind of flow over the surface in big valleys.

Natalie, is there an official word flowy?

Flowy, flowy, I think so.

I like it.

That’s the name of her labradoodle.

Flowy.

The one she’s breeding on the planet Pluto.

Yeah, exactly.

It’s part of that whole creepy breeding process she has going on in her basement right now.

Some of the eruptions on the moon were more explosive, but actually towards the end of volcanism on the moon, stuff was less flowy, let’s say, and actually became much more explosive and we got fire fountains.

So I don’t know if you remember, there’s been quite a few fire fountain eruptions on earth in the last few years.

La Palma had some, I think a couple of years ago, and this is where we just get explosive.

La Palma, the Canary Islands?

Yeah.

So I don’t know if you remember, it was all over the news, 2021, a huge fire fountain eruptions, and that actually would have happened on the moon back in the day about three billion years ago.

So, but again, the magma is too heavy, it’s too dense in order to kind of escape the moon surface.

But generally, it all just rained back down.

So yeah, in general, it won’t be out floating around in space.

Is it different for cryovolcanoes?

Is it different for something that’s sort of emitting sort of ice and…

Yeah, definitely.

So gases will definitely, you know, be able to escape much more easily because they’re lighter.

And it really depends on, it just depends on the individual body and how much gravity it has.

But ultimately, it’s going to be pretty hard for most stuff to escape unless it’s very explosive, like we find an Enceladus or something.

Well, plus the moon has a stronger gravity anyway than probably many of those other moons.

Our moon is one of the bigger moons in the whole solar system.

We got a bad ass moon for how small earth is, right?

Our moon can take your moon any day of the week.

Meet me outside.

We’ll meet you at, meet you in the parking lot behind the school, man.

So, I think that’s all the time we have for questions, but I want to get some final reflection from you, Natalie.

Much of what you described in the questions that related to life, it sounds like we’re looking for life as we know it.

And in the end, wouldn’t that be highly restrictive?

Is there a way to look for life as we don’t know it?

Well, the thing is, we still know that everything in the solar system in the universe has to adhere to the laws of physics and chemistry as we understand them.

So it always doesn’t make sense to start looking for life in some other elementary form that doesn’t make any sense for the way that we understand science.

But it doesn’t mean that another solvent like methane or something couldn’t actually host life.

So we are looking not just at places that have liquid water, but for example, Titan, which is a moon of Saturn, we’re looking at that because it has water, but it’s also got a methane cycle.

So instead of a hydrological cycle, it’s got rivers and rain of methane that comes and goes, and it has clouds that form.

So it’s this active environment, but it isn’t water necessarily that we think the life could be surviving on, but this is all organic based stuff.

So I got it.

So liquid water might be an unnecessary assumption.

Maybe it’s just liquid of some kind.

Yes, you definitely need a liquid to be able to move things around.

So organic material needs to be able to move and find other bits of organic material and to create the basic forms of life.

So without liquid, you’re gonna really struggle.

But even in a really icy environment, there’s always gonna be some liquid at the edges of glaciers or whatever it might be.

So there’s always the potential, but we don’t necessarily need water, we don’t think, but we know that water works because we’ve seen it happen here.

So that’s where we’re initially looking.

But yeah, you know, there could be life based on other forms of things that we don’t currently understand, but it doesn’t make sense to go and look for that because we need to start with what we know and then work out from there because there’s too many, you know, it would just be crazy to start looking for things.

We wouldn’t know how to recognize it or detect it if it didn’t look like stuff that we understand.

Okay, so Paul, I think she’s just trying to prevent people from investigating her basement.

I think that’s clearly, I have felt this entire show was just her just obfuscating and just bruised.

That’s all the time we have, Natalie.

It’s been a delight to have you back.

I forgot how much we missed you over COVID and we’re going to reach for you again because the solar system is a never-ending playground of space probes and new hypotheses and the search for life.

So thanks for being a guest once again on StarTalk.

Thanks for having me.

All right, Paul, we’ll look for you on The Late Show with Stephen Colbert.

You’ll see me there.

There you go.

All right.

This has been another episode of StarTalk Cosmic Queries.

Neil deGrasse Tyson here.

As always, keep looking up.