Hello, and welcome to the Physics World weekly
podcast.
I'm Hamish Johnston.
In this episode, we're going to chat about
the science and fiction
of exoplanets,
which are planets that orbit stars other than
the sun.
I'm joined by Keith Cooper,
a journalist and author who's a regular contributor
to Physics World.
Keith studied physics and astronomy at the University
of Manchester,
and he's written extensively
about astronomy,
astrophysics,
and cosmology.
He's also a big fan of science fiction,
and his new book about exoplanets
is called
Amazing Worlds of Science Fiction
and Science Fact.
Hi, Keith.
Welcome to the podcast.
Hi, Hamish. Thank you for having me on
the show.
To begin with, Keith, we should make it
very clear that exoplanets
are real things.
In fact, in the last thirty years or
so, I think astronomers have discovered thousands of
them. So can you give our listeners
a bit of an introduction
to exoplanets
and and the science of of how they're
studied?
Sure.
This year, 2025, is actually the thirtieth anniversary
of the discovery of the first exoplanets
around a sun like star. Now they discovered
freak planets around pulsars a couple of years
before that, but it was, October 1995 when
the first discovery was made. The planet was
called 51 Pegasi b,
and it's what we call a hot Jupiter,
which if you can imagine Jupiter in our
solar system, it's a big gas bag.
And then you move
it really close to the sun. That's what
this planet was like.
Astronomers had no idea that such planets could
exist. They were expecting
other planetary systems to look like our solar
system with the small rocky worlds closer to
the sun and the big gas giants further
out. So this was a big shock. Took
a little while to understand how this could
be. We we finally realized that the big
hot Jupiters actually did form further out from
the star, but then through interactions with the
protoplanetary
disk migrated inwards. And we actually realized that
a similar migration had happened in our own
solar system. Jupiter and Saturn had migrated in
a little bit,
and influenced how the inner planets formed.
Fortunately, Jupiter didn't go all the way to
the sun. Otherwise, we wouldn't be here today
to have this conversation because Earth would have
been ejected from the solar system long ago.
And since then, since 1995,
we've discovered almost 6,000 exoplanets.
As I mentioned, some are as big as
Jupiter, others are smaller than Earth.
We found that the most common types of
planets that we found so far are what
we call super Earths. These are we believe
they are rocky worlds that up to 10
times the mass of our planet.
We have found planets in what we describe
as the habitable zone, which is a region
from a star where temperatures are just about
right for liquid water, assuming that this planet
has an atmosphere like Earth's.
But we don't know whether any of these
worlds are actually habitable. We don't know much
about them other than their radius and their
mass.
A lot of it is guesswork at this
stage. We have the James Webb Space Telescope
in orbit at the moment,
analyzing these worlds and trying to detect atmospheres
on any of them. It hasn't found any
really yet on these rocky
habitable zone planets.
We've got two more missions launching in in
the coming years from the European Space Agency.
That's PLATO,
which will launch in December 2026 if everything
goes to plan. And then Ariel, which will
characterize the atmospheres of the hot Jupiters that
will launch in 2030.
Of course, we'll still have Webb and Hubble.
We got the extremely large telescope being built
in Chile that's going to be able
to possibly image, directly image some of these,
rocky worlds close to their sun. We we
have directly imaged some planets so far. These
tend to be big,
hot, young planets that are far from their
stand. We we they're still glowing from the
heat of their birth. None of them are
are like Earth. And that's the that's the
thing really. With all these planets, we haven't
found any that are like Earth yet. And
and that's really the quest that most astronomers
are on to find another Earth out there.
I mean, the fact that we haven't found
another Earth, is that is that related to
the sort of biases
within
the way that astronomers,
actually observe these
these, exoplanets,
that it's easier. Well, it's easiest to see
a huge planet very close to its star.
So those are the first things that we
discovered. And are we sort
of narrowing in or focusing in on Earth?
Is it sort of a technological issue? Maybe
not that they don't exist, but that we
can't quite see them yet. Is that safe
to say?
It's definitely a selection effect. But depending on
who you talk to, it may also be
the Earth like planets are rare.
You're right in saying that
detecting
an Earth like world is really on the
very edge of what we could achieve.
James Webb Space Telescope is the only instrument
that we have at the moment
that could potentially do that,
and only in the case of an exoplanet
that orbits a star fairly close to us.
Maybe in in twenty or thirty years,
scientists in The United States have,
an ambition
to launch a they haven't got a proper
name for it yet, but it would it
would be a big giant space telescope with
at least an eight meter mirror, which is
larger than than Webb's 6.5
meter.
And it would be armed with a coronagraph,
which will be able to block out the
light of a star so that we could
actually see the planets, the Earth like planets,
orbiting that star without the stars glare getting
in the way.
Then we may be able to start to
answer whether any of these planets that we're
finding in the habitable zone are really habitable.
But there are there are a lot of
scientists out there who
think that
Earth is really a fluke.
The fact that it is habitable, so many
things had to go right.
Not everybody agrees with that. Some people think
that the scope for life is is broader
than just what we have to offer here
on Earth. Look at look at even in
our own solar system, you know, the detection
of phosphine in Venus' atmosphere still debated. Yes.
But people have talked about microbial life in
Venus' clouds.
Or you go further out. I mean, you
have the moon icy moons of Jupiter and
Saturn that harbor oceans and could have life.
They're very not like Earth.
So
we don't know yet whether Earth like planets
are common. Earth sized planets are probably very
common, but Earth like is a big question
mark. But we have to we we we
shouldn't be,
I guess,
Earth chauvinists, we we we should consider other
habitats that unlike Earth that could still support
life.
And science fiction, you know, can be very
good at doing that. That's right. Yeah. So
so that brings me neatly to my next
question. I mean, we've known about exoplanets for
thirty years, but
I think if you look in fiction, there
is a much longer tradition of
people speculating
about other worlds. I mean, I'm I mean,
I have to say, I I I don't
know much about the history Well
well,
first of
Well well, first of all, you're absolutely right
that that science fiction has portrayed exoplanets long
before we actually knew exoplanets existed.
And
I guess by the time we got to
the nineteen eighties and the nineteen nineties, we
were finding hints.
For example,
the
the infrared astronomy satellite, which was a joint
US, Dutch, UK mission in the eighties, imaged
protoplanetary
disks around beta pic Beta
Pictoris, I think,
and and Vega.
So we had the hints, but we hadn't
found any exoplanets. But going back to the
turn of the twentieth century,
there were two theories about how
planets form.
So one theory was turned out to be
correct that they form from a disk of
matter around a young star coalescing from that
that disk of gas and dust.
The other theory was that a passing star
had come close to the sun and pulled
out some material, and this material had formed
the planets.
And in that model, the planets furthest from
the sun would have formed first. Now I
mentioned this because HG Wells' War of the
Worlds
was written at a time when this was
the prevailing theory.
And it was mentioned in War of the
Worlds that that that was the reason the
the Martians were more technologically advanced than us
on Earth because Mars was older than Earth,
and the Martian species was older than Earth.
I think
that started to change a little. The main
problem at this at the time was,
the problem of angular momentum in in the
protoplanetary
disk and and the sun, and how how
we lost that that angular momentum. It's still
a little bit of a problem,
but we we do know that planets form
from the disc now. We've seen it that
in action.
One of the early,
twentieth century science fiction writers was e Doc
Smith.
He wrote the Lensman series, and before that,
he wrote the Skylark of Space. Now Doc
Smith is famous as a science fiction writer,
but
anyone who eats donuts knows him intimately because
he was the guy who figured out how
to get sugar to stick to donuts. Oh,
wow. I thought sugar stuck to everything.
Yeah.
And and and in in his books, you
know, he had space faring civilizations
visiting other planets around other stars. And in
the twenties and thirties,
more authors, more science fiction writers began to
to have stories along the same lines. Isaac
Asimov,
started writing Foundation in the early nineteen forties.
That was about a galactic empire.
And Star Trek, obviously, got visiting strange new
worlds.
And, you know, if you watch Star Trek
in the nineteen sixties, you could probably be
forgiven for thinking that astronomers already knew all
these worlds were out there. But we didn't
know at the time. It was it was
just guesswork. We needed somewhere for our heroes
to visit. So we had to imagine these
planets.
All those Star Trek planets that look suspiciously
like the back back lot
in Los Angeles. Yes. Yes.
Lots lots of cowboy planets and there was
a, 19 planet, gangster planet.
But
I think science fiction
does have a lot of worlds that are
very much like Earth,
especially in movies and TV.
And that can be forgiven because we can't
send actors to Mars. They, you know, they
have to,
act on stages. They're on Earth in one
g gravity,
and it's just cheaper to to make their
planets look like Earth. But even even written
science fiction has fallen into that trap a
little bit of having lots of Earth like
planets. But of course, as I said, you
need somewhere for your heroes to go. And
if it's a barren cratered world, then you
can't have as many adventures there as you
could on on an Earth like planet. But
one of the things that the science fiction
writer Larry Niven liked to do was he
would have
niche planets where most of the planet was
uninhabitable apart from one niche.
So there was one, planet. So he had
a lot of, I guess, there were, arch
ships or or colony ships that would go
out to planets that their robotic probes had
said were habitable.
So one of the, the ships arrives at
this planet
and finds it's all completely uninhabitable
apart from the top of this one mountain
that happens to peak up out of the
clouds into a sort of a habitable area
in the atmosphere.
And they hadn't realized that their their robotic
survey had just mapped that area and said,
yeah. The planet's habitable.
So they had to set up shop on
on on this mountain.
So it's this one niche.
Other other Alastair Reynolds,
is Sort of like a Goldilocks zone Yeah.
Of a But within the planet. Yeah. Alastair
Reynolds is a more more contemporary science fiction
writer, was
inspired by Larry Niven. And on one of
his fictional planets, Yellowstone, the city is actually
in a big gorge where there's, volcanic vents
and and all kinds of gases coming out
that can sustain an atmosphere just in in
in that gorge, in that valley.
And it may be that we find a
lot of planets are mostly uninhabitable
apart from certain areas. So that brings me
on to Dune and the planet Arrakis. Now,
Arrakis,
Dune's my my favorite science fiction book of
all time.
And I'm sure many listeners saw the recent
movies.
And
in June,
the habitable it's a it's a desert planet
as you can guess from the name. It's
a desert planet, very hot, and the only
habitable area
in the story is at the poles. So
they have the the capital city there, and
and the Equator is practically uninhabitable except to
the natives, the Fremen,
and the big sandworms that that that move
through the deserts.
There was actually a study done by a
climatologist actually here at the University of Bristol,
Alex Farnsworth and his team.
So they did a scientific model. Could a
planet like Arrakis, this desert world, could it
actually be real? We know, does it does
it make sense from a a climate perspective?
And it did, except they actually found that
the habitable area
would be at the Equator and that the
way the climate and the atmosphere would work,
it would make the the poles intolerably hot.
And scientists actually think astronomers actually think that
desert like worlds that are habitable may
vastly outnumber
our temperate earth like worlds that have just
the right amount amount of land and sea.
So so, you know, the planet in June
could be a
a forerunner to the kind of worlds that
we might find that are barely habitable,
but just about, and they may be really
common in in the universe. Another kind of
common planet would be an ocean planet that's
completely
drowned
in ocean.
Maybe with just
little bits of land peeking out here and
there.
So they're like extremes of Earth, and the
extremes may be more common than our finely
balanced temperate planet.
So, Keith, how's how science fiction writers
portray
exoplanets? Has that
changed over the past few decades? I mean,
you mentioned how HG Wells picked up on
this idea that Mars could be older than
Earth,
and incorporated that into his fiction. But have
have more contemporary writers, you know, let's say
over the over the past three decades, have
they picked up on
on on discoveries? You know, for example, are
they writing about life on hot Jupiters, for
example?
Absolutely. Oh, they're not hot Jupiters.
There's a scarcity of hot Jupiters in in
in the fiction, probably because you can't. It's
hard to live there, and you'd have to
be really imaginative to imagine life surviving in
an atmosphere that reaches
possibly up to 2,000 degrees Celsius.
But you're right that the the writers are
more tuned to,
scientific research definitely incorporate that into their work,
and they have done throughout the ages. You
mentioned HG Wells there.
Frank Herbert who wrote Dune,
he got the idea for his book because
he he was a journalist,
and he was commissioned to write an article
about Dunes in California.
And that's where he got the idea from
that form.
There was another writer in, the fifty sixties
called
Hal Clement.
He wrote a book called the, emission of
gravity, which was set on a planet that
has this crushing gravity.
Theoretically,
you know, it makes sense, but realistically, it
probably wouldn't exist. But I actually had sent
to me,
the other week,
by a chap in America, Jim Benford, who's
the the science fiction writer, Gregory Benford's brother.
He sent to me a PDF of an
old,
science fiction fan design from 1960 that had
an essay by Hal Clement. And it was,
about a new fictional
planetary system that he'd invented for a novel
he was going to write. We don't think
he ever actually got around to writing the
novel. But the the the system had this
it was a binary star system, but it
had a planet,
had two planets. And one of the planets
orbits came inside
the other planets for a short time,
very much like Neptune and Pluto.
And Clement argued that that well, I you
you said that this planet that came inside
the other planet's orbit was actually used to
be a moon of the other planet and
it had escaped. And that was the theory
regarding Pluto and Neptune at the time. A
lot of scientists thought Pluto used to be
a a moon of Neptune
and that it somehow escaped Neptune's gravity and
and started wandering on the sun on its
own.
And that was around 1960. The the idea
was was in vogue. So Clements was looking
at the latest research
and incorporating incorporating it into his ideas.
More re more recently,
I spoke to a researcher at the
she's at the Open University now, but she
was at Saint Andrews, Emma Purinan.
And she recently did her PhD on
pretty much the topic of my book,
how exoplanets are portrayed
in science fiction, and what we can learn
from that to,
you know, do better science outreach.
And she
raised the point that
in the last sort of thirty years or
so,
it coincides with the fact that we've discovered
exoplanets, but it's more of an awareness of
the
how damaging
colonies were on Earth, colonialism.
And she says that in a lot of
more modern science fiction,
there tends to be fewer exoplanets
where they have civilizations
that have been settled by Earth, where Earth
has colonized these planets. Because there's a growing
awareness of of how,
detrimental colonialism was.
So that's been incorporated more into modern fiction.
Another,
type of planet that we're finding more often,
rocky planets around what we call m dwarfs.
You may know them more as red dwarfs,
not not the comedy show, but these are
small
cool
red stars. It's like and they have scaled
down planetary systems,
where they're really close to their star.
One,
famous example is Trappist one, which has seven
worlds all packed into the inner 10,000,000
kilometers of of the system.
And because they're so close,
their rotation becomes synchronized with their orbital period,
and they become what we call tidally locked.
So they always show the same hemisphere to
their star. Much like the moon always shows
the same face to Earth. The moon is
also tied a lot to our planet.
So
these are a a a new kind of
world that we've really only started discovering in
the past fifteen, twenty years.
And we're still understanding whether they could be
habitable at all, what the climates might be
like on such a world that, you know,
one side always faces us and the other
side is an eternal night. You know, would
the would the night side be always frozen?
Could an atmosphere distribute enough heat around?
And there was the science fiction writer, Charlie
Jane Anders.
She's a contemporary,
writer. And she wrote a book, The City
in the Middle of the Night, which was
set on one of these worlds. And she
spoke to scientists
about, what life might be like on one
of these planets. And she told me that
as she was writing,
the scientific understanding of these worlds actually changed
while she was in the middle of writing
it. And she was like, oh, well, I
need to go back and start again. She
thought, no, because
I'm too far along in the story. And
she did raise a good point that the,
you know, the point of science fiction is
to tell a story. It's not to be
part of the national curriculum.
But, yeah, you know, she was having to
respond to scientific discoveries as they were being
made. She was responding to that on the
fly.
So that, you know,
the good writers
who really swap up and and and and
do their research,
you know, present
possibilities for planets that that could be true,
that we could find these planets in in
in the future because they're really well realized.
And that's, you know, that's the power of
science fiction. Before we discovered
exoplanets,
you know, science fiction was telling us what
they could be like.
Science fiction got a lot right. And we
also found that truth is a lot stranger
than fiction. So it's it's
been a bit of both. Yeah. And that's
that's what I'd I'd like to talk about
now. If we if we could move back
to to, you know,
actual exoplanets.
I mean, astronomers have discovered some really extraordinary
systems,
very unexpected.
I suppose you've chatted a bit about those
already.
Do you have any favorites,
amongst the the the many types of exoplanets
that we know exist?
Is there one exoplanet or a type of
exoplanet that stands out for you as as
being really interesting?
I've thought about this question a lot.
It's hard to say because we know so
little about the exoplanets.
As as I said, you know, we can
we can measure
how big they are. They're they're sized when,
we see them transit in front of their
star. That's one way that we can detect
them. So when they move in front of
their star, they block some of the star's
light. And the bigger they add, the more
light they block. So we can determine their
size.
We know the mass of some of them
based on their gravitational
how how their gravity tugs on their parent
star.
And that's about it. And we know how
far from their star they are so we
can
estimate how warm they might be. So it's
really hard to say, you know,
people fell in love with the Pandora from
the Avatar films, and that's a fully realized
it's actually a moon, not not a planet,
but we don't know anything like that about
the exoplanets that we detected so far. So
it's hard to to pick one specific one
that you could say would be a favorite.
I do find the planets around Proxima Centauri
interesting. Proxima Centauri is the it's a red
dwarf, but it's also the closest star to
our sun. It's just 4.2 light years away.
So its sheer proximity
is quite tantalizing.
There's also
I give this as a kind of jokey
answer to to this question.
There
are some planets that
could be what we call carbon rich
where they actually have more carbon than oxygen.
That results in all the oxygen getting locked
away
in carbon dioxide and
so you couldn't breathe any there'd been no
oxygen free oxygen there to breathe, so you
can actually live there. But because this
theoretically, there could be so much carbon
within the core of the planet, that carbon
gets compressed.
You could get a solid
diamond within the a huge chunk of solid
diamond, planet sized solid diamond in in the
core of the planet. You know, the surface
would be made of graphite.
So just from the point of view of
a planet made of diamonds, you'd be rich.
So so I always give that as a
jokey answer. And
in regards to whether any planets like that
really exist, we have found stars that are
more carbon rich than oxygen rich. So given
that a star and its planets formed from
the same material,
we'd expect any planets
to orbit those stars to also be carbon
rich.
There was one system in particular called 55
Cancri
that is carbon rich.
But now
astronomers don't believe it's carbon rich enough to
to create a diamond planet. But the potential
is out there.
You know, people talk about going mining asteroids.
Well, imagine mining a car a a carbon
rich planet with all the diamond.
Yeah. Well, I think what if if you
did find an entire planet made of diamond,
maybe the the value of diamond would plummet.
Yes. Exactly. Yes. You'd you'd saturate the market,
I think.
Yeah. That is I mean, I thought about
it as well. And, you know, I I
sort of have to go back to these
hot Jupiters, you know, these huge
gas giants that are very close to their
stars.
And, you know, I just can't work out
in my mind. Because I suppose we have
this vision of of Jupiter as being this
very cold planet and icy, and,
but and the fact that one can exist
very, very close
to to a star just blows my mind.
It, you know, I suppose it rewrites how
we understand
planets and and and sort of the energy,
exchanges between a star and its planets. You
know, it's really,
really interesting, I think.
Well, let me blow your mind a little
bit more with that because they're so close.
As I mentioned earlier, the temperature of their
cloud tops can reach
a thousand degrees Celsius, 2,000 degrees Celsius.
When things get hot, they expand.
So these planets are bloated.
You know, they might have half the mass
of Jupiter,
but they're like three times as big. And
because they're so expanded,
gravity is holding on to their atmosphere very
tenuously, and the the wind from the star,
the wind of radiation from the star, like
the solar wind, is blowing the atmosphere away.
And they have tails like comets. And these
tails are made from, you know, all all
the metals and the hydrogen from from the
atmosphere.
And they're literally evaporating
in front of our eyes. It's remarkable.
So if you, you know, let's say, if
you lived on a on a planet in
that system, let's say a rocky planet
a bit further out, what you would see
in the sky
would be amazing, wouldn't it, if you saw
both this
huge gas giant
and the star as well. It would be
it would be something else, wouldn't it? I
mean, particularly when the star
went below the horizon, but that gas giant
was still there probably glowing in a big
a big tail. And,
yeah, it is it is mind blowing, isn't
it? It is. To think about it.
It it is. And
the only caveat to that is because when
because hot hot Jupiter's migrate
from further out into, you know, really close
to their star. Sometimes they collide with with
with their star. But because they migrate in,
any smaller worlds in the way just get
kicked out. Some get kicked into the star.
Some get ejected from the planetary system altogether.
So it was thought that hot Jupiters would
be
like a single child.
That's starting to change a little bit. We
have started to find a couple of other
planets
that coexist with hot Jupiters.
How that is so, we we don't entirely
know. But, yeah, it it it you know,
depending on how close your planet is to
the star and the hot Jupiter, you can
have many more total eclipses
or partial eclipses.
And, yeah, and there's a huge tail stretching
across the sky.
It would be
remarkable.
Yeah.
Definitely something else.
And and what about fictional exoplanets, Keith? I
mean, you've mentioned a few already.
But is there, is there a favorite imaginary
world of yours?
Endor because of the Ewoks.
No. Joking.
I'll answer this from the scientific point of
view of which ones I think
have the most to say about science and
which I found most interesting to write about
in my book, Amazing World. So I mentioned
Dune and Arrakis.
Another planet was
the world of Gethen,
which was in Ursula K. Le Guin's,
award winning novel, The Left Hand of Darkness
from 1969.
This is an icy planet
with
a habitable strip. So we're going back to
the niches again. This habitable strip around the
equator
where, you know, it gets to five degrees,
10 degrees. It's a bit chilly, but you
can you can live there. And then it's
just these huge ice caps that almost meet
at the Equator.
And
in the novel,
she suggests that
is connected
to stellar activity.
And she even refers to that the planet
will always be like that because of volcanism,
which is absolutely correct.
Volcanoes act as
Earth's,
thermostat.
You have the the the carbon silicate cycle.
So as we know, to our detriment, carbon
dioxide is a greenhouse gas. It warms the
planet.
At the moment, we're undergoing climate change through
artificially dumping tons of of carbon dioxide and
other greenhouse gases into the atmosphere. But, you
know, it exists there naturally. And without it,
Earth would freeze.
I think, you know, the carbon gets cycled,
it gets rained out,
goes into the ocean,
is incorporated
into into life that that that dies, sinks
to the bottom, the carbon gets,
sequestrated into into, you know, in into
the mantle,
and eventually spat back out through volcanoes. So
you go through periods where you've got a
lot of carbon dioxide in the atmosphere and
not so much. And and that regulates
climate
over tens of thousands of years. That it's
like our our planetary thermostat.
So so
Le Guin was absolutely right that, you know,
that would eventually
warm her planet of Gethin and and the
ice caps would retreat.
But what's interesting about it
is Earth has also gone through what we
call it snowball phases at least twice before.
Almost the entire planet was covered in ice.
Yeah. It didn't wipe out life clearly. We're
still here.
And we've
research has shown that it's possible that even
though the ice could reach all the way
down to the Equator,
atmospheric circulation may mean that there's certain areas
that don't freeze over and remain habitable. So
we, again, the niches.
So I just thought
Le Guin there was really,
really smart in in in understanding what makes
plan planets and climates
tick.
So, yeah, I really enjoyed reading about that
planet and and and writing about it because
it was so clever.
Wow. Yeah. I mean, I think for me,
you know, I think the
going back to Star Trek, you know, I
I grew up in the seventies,
and there wasn't much on TV back then,
but there are lots of repeats of Star
Trek.
And,
I mean, almost every episode, they went down
to a planet which, you know, looked suspiciously
like Southern California.
But the the one episode I think, you
know, I think that really struck me,
it was when they went to a a
a planet that was being mined,
and they they sort of encountered this
this
life form that was burrowing through
the rock. And, you know, it was,
what did they describe it as? A silicon
based life form.
And I thought, you know, I thought that
was really, you know, it it sort of
dawned on me then that, yes, you know,
you could of course, life here on Earth
is carbon based,
but maybe somewhere else there would be silicon
based,
life.
I don't know why that really that really
stuck with me. And, you know, I'll never
forget a few years ago.
Matin, my colleague, here on Physics World, he
went
down,
a mine in Yorkshire,
the Bulby Mine, where they're, detecting,
doing
some experiments. I I I don't quite know
the details. But I remember, you know, sort
of laughing to myself that, you know, I
hope,
I hope Bettine doesn't encounter a potash based
life form because it was a potash mine.
You know, it's it just shows that, you
know, forty years later, the the whole concept
of going down a mine and encountering a
strange
life form, stuck with me. So it is
I think it is very powerful, you know,
this idea,
both in fiction and in fact, of imagining
alternative
existences.
And,
I mean, I suppose in a sense it
it it probably can be very useful here
on Earth as well because
if you're,
you know, I suppose the famous incident
or incidents here on Earth is
the discovering that in those vents deep in
the ocean
that there actually can be life.
And, of course, if, you know,
if you're a if you're a biologist
decades ago, you probably wouldn't have believed that
because you would have thought, well, we have
to have sunlight and, you know, we can't
have all these toxic chemicals
spewing out of the Earth. Those would immediately
kill things.
So, you know, I can see how
reading
fiction about exoplanets
and studying them, that that could really help,
scientists beyond physics and astronomy to to understand
the world around us.
So, yeah, it's,
hopefully, some scientists will read, you know, biologists
read your book and maybe be inspired about
their views on life.
I I I certainly hope so.
The the Bulbimine, yeah, that's that's where the,
the dark matter experiment that that I think
they're looking for dark matter particles there. But
just going back to the Star Trek episode,
so that was the episode Devil in the
Dark.
And the yeah. It was a silicon based
life form that was protect it it was
the mother,
the species was called the Horta. The Horta.
Yeah. And and the mother was protecting,
her eggs. So all you know, they when
they realized in the end that the mother
was was was killing the miners and but
when Kirk and Spark realized what was happening,
they made peace and,
and the the heart started doing the mining
for the miners.
But yeah. Yeah. Silicon based life,
it's been talked about.
I from what I understand,
the problem with silicon
based life is is
partly that carbon bonds with with
other atoms to create, you know, organic molecules
a lot better than than silicon does. And
the metabolism
using silicon rather than carbon would be a
lot slower,
I believe.
So whether silicon life could exist,
you know, it's quite speculative.
But it it does go to show that,
you know, we're so obsessed with finding Earth
like worlds that can support life as we
know it.
But how do we know that life as
we know it
isn't the rare kind of life and the
life as we don't know it is the
more common type of life?
And should we be looking at other kinds
of exoplanets that could possibly support different kinds
of life? But it's it's very speculative and,
you know, but that's where science fiction comes
in in in suggesting these ideas. And,
as you say, scientists can
maybe
follow-up on them. And and they have. There's
been there's been papers written about various
planets in science fiction,
a lot about Dune.
So
I I I think there's a a symbiosis
there. And it can definitely be used for
outreach because,
let's face it, most people most members of
the public know about exoplanets from science fiction
from watching Star Wars or Star Trek or
Avatar.
So it is
a really good promotional tool for exoplanet research
that maybe
exoplanet scientists could
make use of more often.
And and you mentioned,
you know, ex existing telescopes, and there's lots
of or hopefully, lots of new telescopes going
to be commissioned
in the future. So, I mean, at some
point, you know, we will
see or hopefully see a smoking gun for
some sort of life. I mean, who knows
when when that'll happen. Do you do you
think that,
you know, when when when we've got that
peer reviewed paper about life on another planet,
is that gonna change our perception of our
place
in the universe?
Or may maybe that perception has changed already
or beginning to change because of these thousands
of exoplanets
that we've discovered already.
You know what? I surprised myself with
what I decided my answer was going to
be to that. I don't think it will.
I think
I mean, chances are that any life we
find out there is gonna be microbial,
which isn't gonna excite anybody. It'll excite the
astrobiologists.
But, you know, that's not
not going to excite anybody, I don't think.
If we found an earth like world, even
if we couldn't tell whether there was actually
life on it,
again, it's so far away. We're not going
to be able to go there. So, you
know, after a few days of excitement, it's
gonna die down. People just gonna get on
with their lives and forget about it.
There's even an argument that, you know, if
SETI discovered a radio signal from another
species light years away,
that that wouldn't change anything because of the
distance. Unless unless they give us
knowledge
and technology that we couldn't have otherwise.
I don't know whether it would affect everyday
life. And at the end of the day,
people are more concerned about, you know, putting
dinner on the table,
you know, paying bills and and just enjoying
their life. And I I don't I don't
think
I I, you know, I'd hope it would,
and it should do, but I don't think
it would have that great an an effect.
I guess what could
have an effect
is if we go back to the nineteen
sixties and the first pictures of Earth from
space,
had a huge effect on on, you know,
the environmental movement at the time. And if
you can imagine a similar picture of an
exoplanet
with oceans and continents and forests and clouds
and and maybe life as well,
I think that could have a big effect.
Yeah. Because I'm I I suppose the thing
is, in a way,
this I this it's a very deeply entrenched
idea in
in people's minds, isn't it, through I I
suppose through fiction and art to a certain
extent. You know, if you if you've watched
all the Star Wars films,
if you watch Star Trek,
if you've read, you know, a bit of
science fiction, then
the idea is there already,
and it, you know, it doesn't seem crazy.
And so
learning about it,
learning that it's true,
you know, that I I don't think that
would blow blow Pina's minds.
I think I think there's an easy way
to test this. There's a lot of people
who believe in UFOs. I don't. But there's
a lot of people who do. And, you
know, when whenever there's a a discovery about
a biosignature
or, you know, possibility of life on the
planet, you get loads of people saying, we
already knew about that. They're already here.
So has life changed for them? You know,
how has their view of of
life and the universe changed
through thinking UFOs are real? I I don't
think it has.
I find UFOs very unimaginative to be true
truthful.
And you can tell that it hasn't really
changed their world view,
at least not for the better.
So I I I think that's quite an
interesting test case. We already have people who
are convinced there's alien life and that it's
here. And so how has it affected them?
And I don't
I don't think
it has too much other than just,
you know, making them believe there's big conspiracies.
Yeah. Well, I suppose that's the other problem,
isn't it? That,
you know, the way things are these days,
you know, the scientists
could announce,
that they found evidence for life and people
wouldn't believe them. But,
that's, you know, that's just the way the
modern world, or the world as it is
at the moment. Well thanks Keith, thanks so
much for,
coming on to the podcast and talking
about your book. And, I'll put a link
in the notes,
for the podcast,
to the book.
Thanks for coming in. Thank you for having
me.
I'm afraid that's all the time we have
for this episode.
Thanks to Keith Cooper for joining me today,
and a special thanks to our producer,
Fred Isles.
Keith's book is published by Reaction Books, and
it's called
Amazing Worlds of Science Fiction and Science Fact.
Look out for a link in the podcast
notes to the book.
We'll be back again next week.
See you then.