0:00

This message comes from NPR sponsor

0:02

Spectrum Business, made to work just

0:04

like your small business. Fast,

0:06

reliable internet, phone and mobile services,

0:09

made to keep up with

0:11

demand and made to deliver on

0:13

a small business budget. Discover

0:15

more at spectrum.com/work. You're

0:18

listening to Shortwave from

0:21

NPR. The

0:24

last time we saw Paul Atreides, he

0:26

was stranded on the harsh desert planet

0:28

Arrakis, trying to outrun a

0:30

giant sandworm to stay alive. Paul

0:37

is the hero in the novel and now film Dune.

0:40

Set in the future, Paul is the

0:42

heir to the fiefdom of Arrakis, aka

0:45

Dune. This planet is

0:47

the only place an important space travel

0:49

good, spice, exists. And in part one,

0:51

Paul joins local Fremen, the people of

0:54

Arrakis, against his mother's wishes. And

0:56

he tries to continue his late father's mission

0:58

of bringing peace to the planet of Arrakis. A

1:01

journey he continues in Dune, part two, out in

1:03

theaters now. It's

1:05

a science fiction tale of mythology, interstellar

1:08

politics, and living in a harsh

1:10

world. But I gotta

1:12

admit, anytime I've read or watched Dune, I'm

1:14

plagued by one train of thought. What

1:17

about the science? How

1:19

would a giant sandworm live on

1:21

a planet like Arrakis? Lucky

1:24

for me, Mohammed Nour has also spent a lot

1:26

of time thinking about all of this. Mohammed's

1:55

thought a lot about all of this because

1:57

in addition to being a biologist, he could

2:00

consults for another famous sci-fi franchise,

2:02

Star Trek. So he

2:04

has a lot of experience with trying to

2:06

figure out how to make fantasy seem realistic.

2:09

I brought him and Michael Wong, an

2:11

astrobiologist and planetary scientist, on

2:13

the show to help me understand if

2:16

the things we're seeing in the Dune

2:18

movies are possible in real intergalactic space,

2:21

not just because we're all Trekkies. I wanted

2:23

to know, are there planets like Arrakis out

2:25

there? Could a desert

2:27

world be changed into something more

2:29

habitable? Habitable for whom? So for

2:31

human life, we require a certain amount

2:33

of oxygen in the air, and

2:36

there probably isn't very much plant

2:38

life pumping oxygen into the air

2:40

on such a desert world, but

2:42

you could, in theory, generate oxygen

2:44

through photochemistry. That is the way

2:46

that ultraviolet light from the star

2:48

can interact with the molecules in

2:50

the atmosphere and cleave them apart

2:52

and create oxygen. So

2:55

for instance, carbon dioxide, CO2,

2:57

has oxygen in it. You can break that apart and create O2.

3:00

You can do the same with water, H2O. That's

3:02

got some oxygen in there. You can break it apart

3:04

and create O2 as well, but

3:07

as we've established, Arrakis is a

3:09

parked world. So

3:11

today on the show, we're talking Dune and

3:14

habitable planets. We nerd out about what we

3:16

love about science fiction and what could actually

3:18

mirror reality. I'm Regina

3:20

Barber, and you're listening to Shortwave,

3:22

the science podcast from NPR. This

3:28

message comes from NPR sponsor, Spectrum Business. Made

3:35

to work just like your small business. Fast, reliable internet,

3:37

phone, and mobile services, made

3:39

to keep up with demand, and made

3:42

to deliver on a small business budget.

3:44

Discover more at spectrum.com/work. This

3:48

message is brought to you by Apple

3:50

Pay. Fussing with plastic cards should

3:53

be a thing of the past in the face of the pandemic. Fussing

3:56

with plastic cards should be a thing of

3:58

the past. Instead, pay the Apple. Apple

4:00

Pay is easy, secure, and built into iPhone.

4:03

All you have to do is set it

4:05

up. Just add a card in the Wallet

4:07

app and you're good to go. This

4:10

message comes from NPR sponsor Capella

4:12

University. With Capella's FlexPath Learning

4:14

Format, you can earn your degree online

4:16

at your own pace and get support

4:18

from people who care about your success.

4:21

Imagine your future differently at

4:23

capella.edu. Okay,

4:27

Michael, Mohammed, let's talk about Arrakis.

4:29

It's dry, it's a harsh desert planet,

4:31

and while humans, you know, the Fremen,

4:33

they do inhabit Dune in this fictional

4:35

universe, a big tension is

4:38

whether it could be more comfortable, more

4:40

livable, through terraforming. So, Michael, let's start out

4:43

really basic. What

4:45

is terraforming and is it doable? So,

4:48

terraforming is basically an imaginary

4:50

process by which

4:52

you take some planet that is not like the

4:54

Earth and change it on

4:56

a global scale to be more like

4:59

the Earth. And for

5:01

Arrakis, it seems like the limiting factor

5:04

for the biology there is the water. It seems like

5:06

all the life there is really starved for water, very

5:09

thirsty, trying to get it wherever it can. So,

5:12

the first step to terraforming Arrakis,

5:16

if one tried to do that, would be to try to find

5:18

a new source of water. Now, where are you

5:20

going to find water? It's a really

5:22

hard problem. You can't

5:24

just like magically put more water

5:26

onto a planet. One

5:28

way you could imagine doing this is to look

5:30

at the icy bodies in the system that Arrakis

5:33

is in. So, maybe there are some

5:35

comets or asteroids that contain a large degree of

5:37

water. If

5:39

you bring them back down to that world

5:42

safely, you know, without causing a mass extinction in

5:44

the process, don't know how you would do that,

5:46

but, you know, imagine that you could. Then

5:49

you could put more water onto Arrakis and

5:52

perhaps raise its habitability that way. People

5:54

often propose terraforming in the context of,

5:58

well, we've ruined the Earth, so we should go simply. It

6:00

would be a billion times easier

6:03

to fix the earth than to create

6:05

another earth. 100%

6:07

agree. Okay, so not super

6:09

plausible for us, but what about Arrakis?

6:13

Could there be a planet full of humongous

6:15

worms? So with

6:17

the worms, one of the concerns I have about that is,

6:19

what does this thing eat? How

6:22

does it derive mass and how does it derive

6:24

energy? I mean, I'm assuming it doesn't have

6:27

some sort of atomic reactor inside its belly or something like that.

6:29

It clearly is consuming something. But

6:32

is there so much life down there

6:34

underground that it can actually acquire that

6:36

much mass? And the answer might very

6:38

well be yes. Maybe

6:41

it's going through and getting just tons and

6:43

tons of really, really small organisms. Now,

6:45

what I thought was really fascinating about those sandworms is

6:48

how they use vibrations to locate their prey. Yes. That

6:51

was very cool. And that is actually something we see in a lot

6:53

of life on earth. Sharks

6:55

are able to use vibrations to water for

6:57

locating their prey. But even worms themselves, you

6:59

may be familiar with something called worm grunting,

7:02

where people will essentially hit sticks on the

7:04

ground to try to bring worms up to

7:06

the surface. So, I

7:08

mean, this idea of basically

7:10

using vibrations in the earth is not

7:12

unprecedented. Michael, so

7:14

in Dune, there are also these plants

7:17

that collect water. Could

7:19

you give us some examples of ways you

7:21

could collect water in a desert planet? Yeah.

7:23

So one actually really interesting way

7:26

is by having salt crystals. So

7:28

salts will actually kind of pull

7:30

the water out of its vapor

7:33

phase into liquid phase. So this

7:35

is a process that in science

7:37

we call delicuescence. And so maybe

7:39

the plants are utilizing

7:41

minerals in this very fascinating way. Wow.

7:43

Okay. There's actually some desert frogs that

7:45

also get like condensate directly from the

7:48

air. Essentially, they call it almost like

7:50

sweating. And they are able to pull

7:52

some of the condensate out. So again, there's precedent

7:54

for this. Mohammed and Michael,

7:56

you are both also Trekkies

7:58

like Michael. So

8:01

let's put Arrakis into a

8:03

wider sci-fi context here. How

8:05

does this planet compare to other fictional worlds? In

8:07

a lot of science fiction, we see

8:10

these single-biome desert planets. If you're a

8:12

Star Wars fan, you may be familiar

8:14

with Tatooine. That's a desert

8:16

planet, although it is in a slightly different

8:18

situation in that it orbits a binary star

8:21

system. So that could

8:23

contribute to some of its desert nature.

8:25

Also I think the most famous one

8:27

in Star Trek would be Planet Vulcan.

8:29

One thing you see with the Vulcans

8:31

that you also see with the Fremen

8:33

is this adaptation to the environment. And

8:35

this is different from what people talk

8:37

about with acclimatization to high altitudes. You

8:39

know how runners will go work out

8:41

at high altitudes so they can sort

8:43

of adapt. That's a

8:45

physiological adaptation. In the context of

8:47

the Fremen or the Vulcans, they're

8:49

actually genetically adapted to their particular

8:51

environment. And there are examples of

8:54

that even here on Earth. If you

8:56

think about people from Tibet, they actually

8:58

have a variant of this gene called

9:00

EPAS-1, which actually allows them to use

9:02

oxygen more efficiently, smaller amounts of it

9:05

more efficiently. And that's similar to something

9:07

we've seen in the context of Vulcans

9:09

in Star Trek and probably something along

9:11

those lines in terms of the heat

9:14

adaptation of the Fremen. What's the

9:16

most realistic fictional planet either of you

9:18

have come across? In

9:20

Star Trek, Andoria is a planet,

9:23

but it's actually a moon of a

9:25

gas giant planet. And

9:28

it's an icy moon. So the

9:30

Andorian people are known to live

9:32

in these very frigid, Arctic conditions.

9:35

And I think this very poetically

9:37

speaks to the idea of habitable

9:39

icy moons that we've discovered right

9:42

in our own backyard. So moons

9:44

of Jupiter and Saturn are

9:47

known to have these subsurface

9:49

oceans of liquid water hiding

9:51

beneath miles of frozen ice. And

9:54

the reason why they're able to

9:56

have these subsurface oceans is because

9:58

of tidal heat. heating. So sometimes

10:01

during their orbit, they're very close

10:03

to Jupiter or Saturn. These moons

10:05

are actually getting pulled into different

10:07

shapes as they're orbiting

10:09

their planet. And that induces friction

10:12

within the moons and keeps the

10:15

subsurface ocean liquid. There's just enough

10:17

heat there to melt that ice

10:19

and have a global liquid water

10:21

ocean. And so this is one of

10:23

the greatest places to potentially go looking for

10:25

alien life in our solar system. The advantage of having

10:27

this water is both you have the opportunity for life

10:29

to arise, but you also have an easy way to

10:32

produce a lot of oxygen too, because it's all it's

10:34

all right there. It's all ready to go. Speaking

10:36

of moons, I love Europa.

10:38

I love Titan. I

10:40

love, you know, Enceladus. Europa

10:42

is around Jupiter, Encellus and Titan is

10:44

around Saturn. And I used to imagine

10:47

life in these oceans like under the

10:49

ice. So as an evolutionary biologist, Muhammad,

10:51

like what kind of life could be

10:53

there? Oh, the most likely

10:55

life we would find, and I think Dr.

10:57

Wong would agree with me on this too,

10:59

is something that's single cell. Because if you

11:01

think about the first couple of billion years

11:03

of life here on Earth, things were single

11:05

cell. It's much easier to get those in

11:07

sort of this liquid environment than or potentially

11:10

in gases. But I mean, with liquid, you have the

11:13

solvent is all right there. There's lots of materials that

11:15

it's easy to build a membrane. That

11:17

is a perfect environment for the origin

11:19

of life, I'd say. Yeah, absolutely. Some

11:21

of the leading hypotheses for the

11:23

origin of life here on Earth situate

11:25

our emergence at these hydrothermal vents,

11:28

these gurgling, bubbling geological

11:30

factories of organic molecules at the

11:32

bottom of our ocean. And there

11:34

are likely those same hydrothermal structures

11:36

at the bottom of the oceans

11:39

of these icy moons, Europa and

11:41

Enceladus. Now, Titan is a very

11:43

different case. So Titan is this

11:45

object, again, orbiting Saturn,

11:48

but it has this very thick

11:50

atmosphere that is full of methane.

11:52

And when methane interacts with

11:54

light from the Sun, it can get cleaved and

11:56

then react with its own

11:58

parts to create these. very

12:00

large and complex organic molecules

12:03

that essentially snow out

12:05

onto the surface but it's not

12:07

snowing snowflakes of water it's

12:10

snowing snowflakes of organic molecules

12:12

and who knows what kinds of weird

12:14

kinds of chemistry maybe even weird kinds

12:16

of life could be floating in those

12:19

hydrocarbon lakes and seas of Titan. Right

12:21

and Michael that actually brings me to my next

12:23

question what worlds are you most

12:25

drawn to and have we found

12:27

planets outside of our solar system like them

12:29

or like moons inside of our solar system

12:32

like them? Well we've been talking about

12:34

some of the worlds that I love

12:36

the most Europa Enceladus and Titan you

12:38

know NASA's planning several

12:41

missions to go back to the outer

12:43

solar system and investigate these worlds for

12:45

their habitability and potentially signs of life

12:47

so launching later this year I believe

12:50

in October of this year will be

12:52

the Europa Clipper mission. Yes and another

12:54

Star Trek connection just right here if

12:56

you watch season two of Star Trek

12:58

Picard it took place in 2024 because

13:01

they did some time travel shenanigans and

13:04

there was a Europa mission that launched

13:06

that year but it actually really takes

13:08

after and mirrors this robotic spacecraft that

13:10

in real life NASA is sending to

13:12

Europa in 2024 this

13:14

year. It's like my childhood dreams are

13:17

coming true and

13:19

Mohammed what kind of science do you

13:21

actually want to see in sci-fi like

13:24

Dune Part 2? Well I always love seeing

13:27

different forms of life than you would

13:29

actually see on earth so in various

13:31

franchises we've seen you know life that

13:33

is maybe not carbon-based and it's truly

13:35

different from life on earth as opposed

13:37

to some existing animal that we already

13:40

have made big or small or a

13:42

combination of two animals we have so

13:44

you mentioned Star Trek earlier one great

13:46

thing in Star Trek was like the folians they don't look

13:49

like anything we have here these

13:51

radically different organisms that live in

13:53

a different environment from what we ever see they live

13:56

at something like 400 degrees Celsius they're

13:58

they're almost crystal insulin in

14:00

a way. And they do have little

14:02

things that look like eyes, but we

14:05

can't actually tell if that's what they

14:07

use. They communicate by vibrating. They're just

14:09

fascinating. What about you, Michael? What

14:11

kind of science would you like to see in Dune Part 2

14:13

and other sci-fi franchises?

14:16

I think in Dune Part 2, I'm looking

14:18

for a fuller explanation

14:21

of all the different life forms and

14:23

all of their interrelated symbiosis

14:26

or food webs that

14:29

can sustain the kinds of creatures that we

14:31

were introduced to in Part 1. Thank

14:35

you, Muhammad and Michael, for geeking out with me.

14:37

That was so fun. I loved it. Thank

14:40

you so much. That was a great time. Thanks for having

14:42

us. I always loved chatting with Dr. Wong and great to

14:44

chat with you as well. This

14:48

episode was produced by Rachel Carlson. It was

14:50

edited by Alman Akan and our showrunner,

14:52

Rebecca Ramirez. Britt Hansen checked

14:54

the facts and Maggie Luther was the audio

14:56

engineer. I'm Regina Barber. Thank

14:59

you for listening to Shortwave from

15:01

NPR. Support

15:17

for NPR and the following message

15:19

come from IXL Learning. IXL Learning

15:21

uses advanced algorithms to give the

15:24

right help to each kid no

15:26

matter the age or personality. Get

15:28

an exclusive 20% off IXL membership

15:30

when you sign up today at

15:33

ixl.com/NPR. This message

15:35

comes from NPR sponsor Rosetta Stone,

15:37

an expert in language learning for 30 years.

15:40

Right now, NPR listeners can get

15:42

Rosetta Stone's lifetime membership to 25

15:45

different languages for 50% off. Learn

15:48

more at rosettastone.com. stone.com/npr.

15:52

Be Npr app cuts through the

15:55

noise, bringing your local, national and

15:57

global coverage. No pay new

15:59

profits, No nonsense. Download it in

16:01

your app store today.