July 2, 2025 • 34 mins
Is it humanity's destiny to colonize Mars? Jorge talks to Martian experts to learn whether we can ever move to our sister planet.
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Speaker 1 (00:00):
Hey, welcome to sign Stuff, a production of iHeartRadio. I'm
hoor Cham and today we are going to Mars. We're
going to find out what it's like there on our
red sister planet and if we could ever transform it
to make it livable for billionaires and space colonists. We're
going to talk to a NASA expert as well as
(00:21):
a comparative planetologist who specializes in the Mars atmosphere. So
pack your spacesuit and bring extra sunscreen because we are
moving to Mars for the next half hour. Here unsigned stuff, enjoy.
(00:44):
Hey everyone, here are some facts you might not know
about the planet Mars. It's about half the diameter of Earth.
It takes almost two earth years to go around the Sun.
The gravity there is forty percent what it is year.
It's home to the largest mountain in the Solar System,
(01:04):
which is two and a half times taller than Mount Everest,
and it's home to the biggest canyon in the Solar System,
which is five times deeper than the Grand Canyon. On
February twenty twenty one, that says Mars rover Perseverance recorded
audio from one of its external microphones. So here's what
(01:25):
it sounds like to be on Mars. Seems pretty peaceful, right,
So threecap Mars is smaller, so everything there would be closer.
(01:50):
You technically be half as old if you count your
age in Mars ears. You can duncate basketball more easily
there because the gravity is lower. Its amazing sights to see,
and at least for now, there are no crowds. Sounds
like a pretty nice place to move to, right And
in fact, people have been talking a lot about moving
(02:12):
to Mars recently, and it's not just because a crazy
billionaire is investing in it. Some people say it's clear
we might run out of space here on Earth someday,
or we might ruin it with nuclear war or environmental disaster,
in which case it would be nice to have a
backup place to move to. And others say it's human
destiny to move beyond Earth and conquer the stars, starting
(02:36):
with the closest planet to us. But as we'll learn today,
Mars is not quite the ideal relocation destination to explore this.
Today's episode is split into two parts. First, we'll ask
could we move there right now? What's it like there
on Mars? And could we survive living there? Second, we'll
(03:00):
talk about the idea of terraforming Mars, which is the
idea that we can change Mars to make it more
like Earth. What would it take and is it even possible?
All Right, the first person I talked to was doctor
Sandra Sillystrom, scientist at NASSE. Well, thank you so much,
(03:21):
Actor Silistrom for joining.
Speaker 2 (03:22):
Us, Thank you for letting me come here.
Speaker 1 (03:25):
Can you tell me who you are and what you do.
Speaker 2 (03:27):
So I am an astrobiologist looking for life in the universe,
and particularly looking for life on Mars. So I'm currently
part of the science team from the NASA Perseverance Rover
that's currently roving Mars and collecting sample for Mars Super turns.
So bringing rocks back from Mars.
Speaker 1 (03:48):
Well, that's amazing and so cool. To start us off,
can you describe for us what it's like on Mars, Like,
what is the atmosphere, like, what is the terrain there?
Speaker 2 (03:59):
Well, so, it's not a very nice place to be
for living things and humans. It's a very hostile place.
It's cold and very dry, so there's no lands or animals.
It's just rocks, loose sand lying in dunes, and the
atmosphere is very thin. The pressure on The surface of
(04:20):
Mars is on a one percent what we have on
the surface of Earth.
Speaker 1 (04:25):
What does that mean one percent?
Speaker 2 (04:26):
It means there's no oxygen or anything for us to breathe,
but it also means there's no protection against radiation coming
in frown space. So it's not a very nice place
to visit.
Speaker 1 (04:40):
And how cold is it there?
Speaker 2 (04:41):
It's typically below freezing. It can go down to less
than one hundred degrees celsius and it rarely goes above
freezing or zero degrees celsius.
Speaker 1 (04:52):
For those of you that prefer fahrenheit. Mars has an
average temperature of about minus eighty degrees fahrenheit, and in
the North and South Poles it can get as cold
as minus two hundred and twenty five degrees fahrenheit.
Speaker 2 (05:07):
And it's very dry because there's no running water on
the surface and almost no humidity, so it's a very
dry place, basically a dry desert, cold dessert.
Speaker 1 (05:17):
Is the whole planet like that or only parts of it?
Is there any variation?
Speaker 2 (05:21):
Well, in terms of climate, it's pretty similar. I mean
yet equator. You can have sometimes actually above freezing a
couple of days, and it's colder of course at the poles,
but in general it's below freezing all over the planet,
plus very dry.
Speaker 1 (05:38):
So what would happen if I just teleport it to
Mars right now without any protection? What would happen to me?
Speaker 2 (05:44):
I think you would die pretty fast. I mean, first
of all, because there's no oxygen right, so you couldn't
breed anything. So I think that would kill you before
you froze to death. You will definitely not survive very long.
Speaker 1 (05:57):
I see now is the problem that there's no air
for that, the air that is there doesn't have oxygen or.
Speaker 2 (06:02):
Both both, so it's a low pressure environment. You would
need some kind of pressure suit, but you also would
need oxygen to bring with you to breed. Right the
atmosphere it's ninety five percent CO two and there's basically
no oxygen, so I don't remember the exact number, but
it's below one percent.
Speaker 1 (06:21):
What's Mars always like it is right now? Or did
it have a different history?
Speaker 2 (06:25):
So actually, if you go there and just take picture
of the surface, you actually see there's a lot of
feature indicating that we're flowing water at some point. So
there are water on Mars, but most of it is
either frozen at the poles, or just beneath the surface.
But at some point some of that water actually flowed
and it carved out like meandering river structures. You can
(06:48):
see deltas at the end of rivers into the lake.
Speaker 1 (06:52):
Wow, how long ago was that?
Speaker 2 (06:54):
This was a long time ago, so maybe aund four
billion years ago, so very early in the story of Mars.
Speaker 1 (07:01):
So four billion years ago, if you went to Mars,
you would see lakes.
Speaker 2 (07:05):
And rivers, yeah, presumably.
Speaker 1 (07:07):
And clouds and brain yeah. Oh what about the atmosphere?
Was it always one percent or was it different?
Speaker 3 (07:15):
No?
Speaker 2 (07:15):
So it's believed that the atmosphere were thicker, and this
is one of the reasons people think there's no water now,
is because the atmosphere creates pressure, right, and the pressure
makes the water be able to be liquid and not frozen.
So what people think is that there was a thicker atmosphere,
but that disappeared quite early in the history of Mars.
(07:36):
And when the atmosphere disappeared, the liquid water also froze.
Speaker 1 (07:41):
Oh, so it's due to the lack of atmosphere that disappeared.
Do we know what happened to the atmosphere? Why did
it go away?
Speaker 2 (07:49):
So this is also one big research topic about Mars,
and one of the reasons is there's no magnetic field,
and also Mars has less gravity they hold atmosphere.
Speaker 1 (08:01):
Okay, so it sounds like Earth and Mars were sort
of like twins at the beginning. I mean they were
very similar, rocky, there were lakes, there was water, there's
a thick atmosphere. But now Earth it's super different than Mars.
Speaker 2 (08:13):
Yes, so that makes it also very interesting. One is
teeming with life and you have the oceans a lot
of life, but the other one is like a dry desert.
Do you also have venos Actually, oh right, Venus, which
is almost the opposite because they have too much atmosphere
and it's very warm. Instead, it's covered by that thick case,
(08:35):
so it's hard to serve the surface and if you
try to land something, it kind of dies within a
couple of minutes because it's the heat is so high. Wow.
Speaker 1 (08:44):
So it's like there were triplets. They're all like the
same and they all took different paths.
Speaker 3 (08:48):
Yeah, I see.
Speaker 1 (08:50):
Okay, So there's a lot of talk now about going
to Mars, maybe establishing a colony there, exploring it. Is
it a place where humans could live? Are there resources there?
For us to live out the land or do we
have to bring everything with us like a camping trip.
Speaker 2 (09:06):
So there is a lot of research going into city
to resource utilizations. This is like using stuff on ground.
There are some resources. For example, you could take the
CEO two and then split that and make O.
Speaker 1 (09:21):
Two and so we have that technology to turn COE
two back into oxygen.
Speaker 2 (09:25):
Yes, hopefully we'll make some way to make oxygen so
you can breathe, and then we would have to make
food and also shelter. So one of the big problems
because we don't have that atmosphere is radiation. So the
radiation level on Mars is much higher than on Earth.
So one thing if we go there is to build
(09:46):
a shelter that you would maybe be able to manufactures,
although there's rock materi lying on the surface like a
dome to protect from radiation.
Speaker 1 (09:56):
Like, you couldn't just rely on your suit or a
camping tent. You need a thick wall to protect you.
Speaker 2 (10:03):
Yeah, maybe you could go there and stay for a
shorter time in some like inflatable type of habitat, but
then if you want to stay longer, you would probably
need to build some type of thicker like a dome.
Speaker 1 (10:15):
I see.
Speaker 2 (10:16):
Another thing people are thinking about. So there seems to
be caves, so you would be able to, you know,
live in a cave or something, because then you would
have automatically that prediction.
Speaker 1 (10:28):
I see, But then you might run into Martian bears.
Speaker 2 (10:31):
Well I don't think.
Speaker 1 (10:32):
So, okay. The last thing I talked to you, doctor
Sillystorm about was whether we could grow food on Mars
right now? Okay, so maybe we have energy shelter oxygen there.
What about food? Is there is there a possibility to
grow food there?
Speaker 2 (10:51):
There've been some scientific tests where they kind of grow
things and Martian analog soils, and it seems possible. One
problem is that there's toxic things in the Martian soil
that's not very good. There's type of salt called percurates,
which is quite common on Mars, that is not very
(11:13):
beneficial for the growth. You need to add like nitigen phosphorus,
which may not be abundant and not I mean, the
sun is also less strong on Mars because we're further away,
so you need to have netlives or something to get
the photosynthesis. You have plenty of seal too, so that's
not a problem.
Speaker 1 (11:35):
Okay, to recap. Mars is not the dream destination some
movies make it out to be. In fact, it seems
pretty dangerous to live there. It's freezing cold. There's very
little air or oxygen while the water is frozen at
the poles. You can't really grow food there. You need
to wear a pressurized suit the whole time, and most
(11:57):
likely you have to live in a cave that's not
peaceful or relaxing at all. Now, there is something that
serious scientists think we can do to make Mars a
nicer place to live, and that is terraforming. So when
we come back, we'll talk to an expert about what
(12:18):
that is and whether it could ever work. Don't go anywhere,
we'll be right back and we're back. Okay, we learned
that Mars is not a cozy place. It's not nearly
(12:39):
as bad as the other planets in our Solar System,
but still living there would be like living in Antarctica,
except there's almost no air to breathe. There's a ton
of radiation, and if you took off your spacesuit you'd die.
This is why people have talked about terraforming Mars, which
is to change at mosphere. Now to fill us in
(13:02):
on how that works and whether it's possible reached out
to a Mars terrorforming expert. Doctor Francois Forge is an
astrophysicist who has worked on many space missions for NASA
and the European Space Agency. Here's how he describes what
he does.
Speaker 3 (13:20):
So, I'm a planetary scientist. I study mostly the atmosphere
on other planets and in particular Mars. I've been working
on many a space mission on the ground and in orbit.
I'm among the person who does climate modeling, the same
thing you do on the Ears to do climate prediction,
but we apply these models to other planet, in particular
(13:40):
planet Mars.
Speaker 1 (13:41):
The start off, what is it like in Mars if
we were together there?
Speaker 3 (13:45):
And mass today has many similarities with the Ears because
the length of the day is twenty four hours and
forty minutes. You have seasons just like on the Earth.
Because the tilts of the axis of rotation is about
the same that on Earths. As the consequence, you have
a low pressure system jet. When you have moonsunjets, you
have many similities. Of course, it's different because it's much drier,
(14:09):
the pressure is very low. You have on average six
hundred and ten million bars, but that's one hundred time
less than on the Earth, so it can be very
cold that it deserts like planet.
Speaker 1 (14:22):
Next, I ask him to describe what terraforming is. Now,
you wrote a paper about this idea of terraforming bars,
can you explain to us what terraforming is.
Speaker 3 (14:34):
Okay? Terraforming is to modify your environment at the planetary
scale so that you can either make life easier for humans,
or you can also a low life, typically terrestrial life,
to grow and develop there, and ultimately you can even
imagine completely adapting it to a human life.
Speaker 1 (15:00):
According to doctor Farge, there are three levels of terraforming.
It's sort of like when you go to the spa
and you get a choice of three levels of treatment.
You can get just a bag massage, or you can
get the full body massage, or you can get the
full body massage plus the modbath, the hot stones and
those little cucumbers that cover your eyes, or you can
(15:23):
think of it like levels in a video game. They're
all terraforming, but each level gets harder and trickier. Here's
how doctor Farge describes each level.
Speaker 3 (15:34):
One is to directly raise the pressure so that you
can walk around without a spacesuit, a seconetist who adapts
mass to some form of terroristial life, and finally to
adapt mass for humans to be just like the Earth.
Speaker 1 (15:49):
Interesting. There's three levels of terraforming.
Speaker 3 (15:52):
Yeah, and there are side options.
Speaker 1 (15:54):
Now we'll get into each of these levels, but first
I was curious about where the side came from.
Speaker 3 (16:02):
This is not a new idea. It's something you can
find in many science fiction books, movies, even games. It's
quite a popular concept. Ellen Musk has been popularizing it
because he wants to do that. But in reality, if
you look at the technical and scientific literature, there are
very very little studies, not many studies about that, so
(16:26):
you can become a specialist quite quickly. So the point
is to say that there have been some speculations, some
scientific studies in the seventies and the eighties. A key
scientific studies was published in nineteen ninety one by Chris McKay,
Riot Tune, and Jim Casting. They were all together at
(16:47):
the Nazaims Research Center. I was there just after this,
so I know them well. And this is really something
that is at the basis of many of the speculation
that you can read today in the pular literature and
stuff like that, and lots of the concept that I
will describe today are in fact described very well in
this interesting paper.
Speaker 1 (17:08):
Okay, to start, here's level one of terraforming Mars, and
that is to simply raise the atmospheric pressure.
Speaker 2 (17:17):
There.
Speaker 1 (17:17):
As mentioned before, the air on Mars is one hundred
times thinner than it is on Earth, so all you
have to do is make more air.
Speaker 3 (17:29):
So now let me go to the first step, that
is to raise the atmospheric pressure so that you can
live without a spacesuit. And the side effect of this
will be too allow to have liqid water on the
surface more easily.
Speaker 1 (17:41):
Can I just ask why does the low pressure require
you to use a space suit?
Speaker 3 (17:45):
Well, there are two reasons. The first one is the
fact that if you go to Mars right now, you
can't have liquid water at all because water will boil
at two three degrees celsius. That means that, for instance,
if you walk around you're a saliva will boil and
your blood will want to boil as well. At thirty
seven degrees you're well above the boiling point, so you're
(18:07):
like a pressure cooker. You don't want to do that.
Speaker 1 (18:12):
Yeah, not having your blood boil would be nice. The
second reason you need a pressure ized suit is that
at those low pressures there wouldn't be enough oxygen atoms
for your lungs to breathe, even if you wore a
pure oxygen mask. So clearly it would be nice to
raise the air pressure on Mars, But how would you
(18:34):
do that?
Speaker 3 (18:37):
So the conclusion you need a space suit today, and
if you don't want a space suit, you need to
find a way to raise the pressure of the atmosphere
on Mars up to at least one hundred twenty millibars
typically okay, and that's a lot because right now on
Mars you have six midi bars of mostly CO two.
(18:59):
So the question is how can you raise the pressure
up to one hundred and twenty million mars or even higher?
Speaker 2 (19:05):
Okay?
Speaker 3 (19:06):
So you need some gas. And they had this idea
that especially in the polar regions, there should be frozen
COEO two ready to be released. So they say that, mmm,
we think that if we can heat the pole, we
can sublime in other world, transform the seal to ice
(19:27):
into seal to gas sufficiently so that you increase the
amount of seal to gas.
Speaker 1 (19:35):
Okay. So one idea to raise the pressure on Mars
is to take all the CO two ice we see
in Mars' north and south poles, melt it so it
turns to gas, and fill up the atmosphere with it.
Now scientists think that you wouldn't have to melt all
that coeo to ice. That'd be like melting all the
(19:56):
ice in our north and south poles. You could do
it by triggering global warming.
Speaker 3 (20:04):
Seal two, by the way, is a greenhouse gas, so
if you increase the amount of gas, there could be
a runaway greenhouse effect in other worlds. You heat a
little bit the polese, it really is a little bit
of seal two s to hat the planets, and then
you have a runaway process that sublimes all the CO
two around and suddenly you have a very nice thick
(20:26):
atmosphere made of seal two.
Speaker 1 (20:29):
Yeah, what could go wrong? All right? So then how
do you get this global warming started? And this is
where things start to get a little science fictioning.
Speaker 3 (20:42):
On this basis you may have heard. All we have
to do is to initialize this, for instance, by using
mirrors to hit the poles of mass, and that could
trigger this runaway climate change that will suddenly transform mass.
Speaker 1 (21:00):
So one idea is to float mirrors in space around
Mars and point them so that they focus the light
from the Sun to the North or South poles, sort
of like a giant space magnifying glass. And from there
the ideas get even crazier.
Speaker 3 (21:20):
Some people have suggested that you could spread the I
don't know, very dark material on the cap and sudden
need will absorb the sola heat and go into this process.
If you know Ellen Musks, it goes around with a
T shirt where it's threetened nuke mass. And this idea
is that, okay, let's release the coal two frozen at
the poles by putting nuclear bombs and it will sudden
(21:43):
nut ones from MASSO.
Speaker 1 (21:47):
That's right. One idea is to paint the North and
South poles black so they absorb more heat, and the
other idea is to explode nuclear bombs to vaporize the
North and Sells poles. Like I said, what could go wrong?
But not all ideas are it this destructive. Another way
(22:08):
to cause global warming is to simply pollute the Martian atmosphere.
Speaker 3 (22:15):
A very popular weight that has been studied was to
make factories and create super efficient greenhouse gas. With the
fluoro carbon. For instance, you can make artificial greenhouse gas
that will really create a strong greenhouse effect with only
a few part per millions. So factories will be enough
(22:36):
to create that if you find the material to make them.
We could invent aerial salts metallic carrosalts with the form
of a needle that will be especially optimized to also
create a very efficient greenhouse effect.
Speaker 1 (22:53):
Okay, that's terraforming. Level one increasing the pressure so we
don't need spacesuits to walk around. Level two is having
life grow on Mars.
Speaker 3 (23:08):
Step two will be to have plants than life that
could survive on Mars, to adapt mass in a way
that you could imagine, have plants, algae, something living that
could survive and thrive on the surface. So some people
will find that exciting because you bring life to somewhere
(23:28):
else down on the Earth. Some people will be motivated
by the fact that plants will be a way to
modify an atmosphere. For instance, photosynthesis could transform CO two
into oxygen, and this is a way to transform Mars
in something more suitable for humans.
Speaker 1 (23:47):
That sounds great. Why doesn't that work?
Speaker 3 (23:51):
The reason is that life is very good as growing everywhere,
even if it's called one acidic whatever. But life requires
liquid water on the Earth is very simple. If there
is liquid water, you have life. Even if it's salty water,
if it's at minute ten degrees, if it's very hot
(24:11):
water at the bottom of the ocean at one hundreds. See,
it's okay. Life is happy. But you need liquid water.
If you are only ice, live stops. If you have
only water vapor, life stops. So the question is how
to get liquid water on Mars.
Speaker 1 (24:29):
Okay, this gets a little bit technical, but basically, because
Mars has low pressure and low temperature, water only really
exists as solid ice or vapor, which is a problem because,
as doctor for j said, life needs liquid water. So
you don't only have to raise the pressure in the atmosphere,
(24:51):
you also have to raise the temperature. There is good news, though.
Speaker 3 (24:57):
There have been studies that show that life simple. Life
like ALGs and even some plants can be happy with
the low pressure atmosphere. They don't need as high as
an atmospheric pressure than what I describe for human but
you need liquid water. And to have liquid water, the
absolute pressure must be about six point one meter bars.
Speaker 1 (25:20):
Okay for level two You don't need to raise the
pressure as much as in level one, but you do
need to raise the temperature, which you might have already
done if you trigger global warming to melt the CO
two in the North and South Poles. All right, when
we come back, we'll tackle the last level of terraforming Mars,
(25:42):
the boss level, which is making Mars just like Earth.
Don't go to another planet just yet. We'll be right back.
Welcome back. Okay, come to the boss level of terraforming Mars,
(26:04):
the ultimate treatment in our planetary spa many making Mars
just like Earth. And here the idea is not just
to make the pressure on Mars the same as on
Earth so you can walk around without a pressureized spacesuit,
or to make the temperature high enough to have liquid water.
This is going all the way.
Speaker 3 (26:27):
Step NUMBA three is really science fiction, but we've been
there since the beginning. So it's to give mass a
breathable atmosphere for humans. That will be the real terrorformation
that you can dream of in science fiction movies. You
go around, you walk around, just like in Star Wars,
all these planets.
Speaker 1 (26:49):
Imagine stepping out the door of your house on Mars.
You're not wearing a spacesuit. The temperature is a little nippy,
but not freezing. Above you, there are clouds blocking out
some of the harmful radiation coming from the sun, and
you take a deep breath. The air is a little dry,
(27:12):
but it's not boiling your saliva. And best of all,
it has oxygen, sweet, refreshing ly sustaining oxygen. And you
go for a nice run among the plants that are
growing on Mars, which is super fun because, as I said,
the gravity in Mars is forty percent what it is
(27:32):
on Earth, so it's like jumping around a bouncy castle.
Speaker 2 (27:36):
Whoo.
Speaker 1 (27:38):
That is the final level of transforming Mars. So what
would it take to get us there?
Speaker 3 (27:49):
So of course this means a lot of thing. First,
you need, as we discussed before, enough oxygen.
Speaker 1 (27:55):
Are there any ideas of where we would get all
this oxygen?
Speaker 3 (27:58):
No oxygen? No, No oxygen is easy because oxygen you
can get it from water. You can process water. You
have lots of water on Mars, have to admit so
water will be busy. You take water, you can electrolyize water,
so you can create oxygen. But you cannot be pure
oxygen because pure oxygen is dangerous. Everything tends to catch fire,
(28:20):
and it's very, very dangerous. It's a little toxic in
some way. If you breathe pure oxygen for some time,
you can have some disease, the Row and Smith effects
like that. It's inflammatory. In any case, you need to
dilute oxygen with another gas. Some on the Earth you
have nitrogen, but we don't have nitrogen on Mass.
Speaker 1 (28:40):
So the main problem in making Mars air breathable is
not oxygen. You could make it on Mars from water.
The problem is everything else that air needs to be breathable.
The air we breathe on Earth is twenty one percent oxygen.
The rest has to be something else, but it can't
be CO two, which is most of what's there on
(29:02):
Mars right now.
Speaker 3 (29:05):
You need to decrease the amount of many gases that
are toxic, like carbon monoxide carbon dioxide below a certain
level otherwise you have problems. You need to have less
than ten million bars of CO two typical clear and
less than point one million bars of carbon monoxide otherwise
you have big problems.
Speaker 1 (29:24):
When you are a human, okay, then you might think, well,
when you made oxygen from water, you also made H
two or hydrogen gas, right, could you use that to
dilute the oxygen?
Speaker 3 (29:40):
Well, no, because hydrogen and oxygen tends to react and
if you have sparkles, you explode, so you don't want
that either.
Speaker 1 (29:52):
All right, This brings us to what seems to be
the main problem with any of these terraforming plants, which
is that Mars doesn't have all the things we need.
If you're trying to pressurize the atmosphere or cause global
warming with CO two, there isn't enough of it on
Mars right now. All the missions we've sent there, like
(30:14):
the Mars Reconnaissance Orbiter, the Mars Global Surveyor or Mars
Odyssey have all found that there's not enough CO two,
either frozen in the North and South poles or absorbed
on the ground. And if you're trying to fill the
atmosphere with breathable air, you need a lot of nitrogen
or our gun, which Mars doesn't really have. And this
(30:37):
is where we run into the definition of what it
means for something to be possible. Some people say at
this point, well, you could bring the CO two from
Venus or Earth like ship it using rockets, or you
could go out to the asteroid belt, round up about
ten million comets and somehow get them to crash land
(30:59):
on Mars because comments have water and carbon monoxide. But
the sheer scale of these solutions start to get a
little ridiculous, or at least really really expensive, or expensive
is beyond the problem.
Speaker 3 (31:19):
In other words, you cannot do it with a technology
that we can imagine.
Speaker 2 (31:23):
Now.
Speaker 3 (31:24):
You may be able to do it if you use
one ten million commets that you move and bring to Mars,
but that's beyond our technology, completely beyond. We have no
energy to do that. Maybe in five hundred years we've
discover an infinite source of energies, but right now it's impossible.
That's my opinion. But it's a debate. If my colleague
(31:44):
Edwin Kite was here, it will scream and say, oh, Francois,
you're dead wrong. I will show you that you can
do it.
Speaker 1 (31:53):
And that's kind of where we're at. It's a debate.
Some people say it is technic possible to change Mars,
even if it takes an almost infinite amount of energy,
and we didn't even get to the ethical questions about
terraforming Mars. Some people argue that we shouldn't change Mars
(32:14):
that we should leave at pristine kind of like a
national park. And some say there could still be Martian
life there, maybe hidden under the surface, and that changing
Mars would be a huge act of genocide. So whether
we could or should terraform Mars, the answer seems to be,
(32:36):
maybe we should clean up our own planet first, all right.
To end this episode, I asked both our experts if
they would go to Mars.
Speaker 2 (32:46):
I tend to say no because if you go to Mars,
you have to commit two years at least to go there,
and I have a family and I don't want to
be away for like two years. I mean, it wouldn't
be cool to go to Mars. If you could go
there for a month, would be cool just to go
and go to a clear different environments.
Speaker 3 (33:05):
Me. I'm still a dreamer. I like astronauts, so I
will dream of going to Mass as an astronaut, but
to do expedition to Mars to explore and study Mass
and come back and leave Mass as clean as possible.
So I don't want to colonize Mars, and I don't
want to terraform Mars.
Speaker 1 (33:26):
Sef nasa Issa said doctor Frage. We needed to get
on this rocket tomorrow and go to Mars. You would go, Yes,
I will.
Speaker 3 (33:34):
I'm fond of such adventures.
Speaker 1 (33:39):
All right, thanks for joining us, See you next time
you've been listening to Science Stuff. Production of iHeartRadio written
and produced by me or Hm, edited by Rose Seguda,
executive producer Jerry Rowland, an audio engineer and mixer Kasey
peprom The same recording of Mars is credited to NASA
(33:59):
jeep Yale call Tech l A N L C N
E S C N R S and is E A supero.
Available on the NASA website at Science dot nasa dot gov,
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Be sure to subscribe to Science Stuff on the Arheart
(34:19):
Radio app, Apple Podcasts, or wherever you get your podcasts,
and please tell your friends we'll be back next Wednesday
with another episode.
Hey, welcome to sign Stuff, a production of iHeartRadio. I'm
hoor Cham and today we are going to Mars. We're
going to find out what it's like there on our
red sister planet and if we could ever transform it
to make it livable for billionaires and space colonists. We're
going to talk to a NASA expert as well as
(00:21):
a comparative planetologist who specializes in the Mars atmosphere. So
pack your spacesuit and bring extra sunscreen because we are
moving to Mars for the next half hour. Here unsigned stuff, enjoy.
(00:44):
Hey everyone, here are some facts you might not know
about the planet Mars. It's about half the diameter of Earth.
It takes almost two earth years to go around the Sun.
The gravity there is forty percent what it is year.
It's home to the largest mountain in the Solar System,
(01:04):
which is two and a half times taller than Mount Everest,
and it's home to the biggest canyon in the Solar System,
which is five times deeper than the Grand Canyon. On
February twenty twenty one, that says Mars rover Perseverance recorded
audio from one of its external microphones. So here's what
(01:25):
it sounds like to be on Mars. Seems pretty peaceful, right,
So threecap Mars is smaller, so everything there would be closer.
(01:50):
You technically be half as old if you count your
age in Mars ears. You can duncate basketball more easily
there because the gravity is lower. Its amazing sights to see,
and at least for now, there are no crowds. Sounds
like a pretty nice place to move to, right And
in fact, people have been talking a lot about moving
(02:12):
to Mars recently, and it's not just because a crazy
billionaire is investing in it. Some people say it's clear
we might run out of space here on Earth someday,
or we might ruin it with nuclear war or environmental disaster,
in which case it would be nice to have a
backup place to move to. And others say it's human
destiny to move beyond Earth and conquer the stars, starting
(02:36):
with the closest planet to us. But as we'll learn today,
Mars is not quite the ideal relocation destination to explore this.
Today's episode is split into two parts. First, we'll ask
could we move there right now? What's it like there
on Mars? And could we survive living there? Second, we'll
(03:00):
talk about the idea of terraforming Mars, which is the
idea that we can change Mars to make it more
like Earth. What would it take and is it even possible?
All Right, the first person I talked to was doctor
Sandra Sillystrom, scientist at NASSE. Well, thank you so much,
(03:21):
Actor Silistrom for joining.
Speaker 2 (03:22):
Us, Thank you for letting me come here.
Speaker 1 (03:25):
Can you tell me who you are and what you do.
Speaker 2 (03:27):
So I am an astrobiologist looking for life in the universe,
and particularly looking for life on Mars. So I'm currently
part of the science team from the NASA Perseverance Rover
that's currently roving Mars and collecting sample for Mars Super turns.
So bringing rocks back from Mars.
Speaker 1 (03:48):
Well, that's amazing and so cool. To start us off,
can you describe for us what it's like on Mars, Like,
what is the atmosphere, like, what is the terrain there?
Speaker 2 (03:59):
Well, so, it's not a very nice place to be
for living things and humans. It's a very hostile place.
It's cold and very dry, so there's no lands or animals.
It's just rocks, loose sand lying in dunes, and the
atmosphere is very thin. The pressure on The surface of
(04:20):
Mars is on a one percent what we have on
the surface of Earth.
Speaker 1 (04:25):
What does that mean one percent?
Speaker 2 (04:26):
It means there's no oxygen or anything for us to breathe,
but it also means there's no protection against radiation coming
in frown space. So it's not a very nice place
to visit.
Speaker 1 (04:40):
And how cold is it there?
Speaker 2 (04:41):
It's typically below freezing. It can go down to less
than one hundred degrees celsius and it rarely goes above
freezing or zero degrees celsius.
Speaker 1 (04:52):
For those of you that prefer fahrenheit. Mars has an
average temperature of about minus eighty degrees fahrenheit, and in
the North and South Poles it can get as cold
as minus two hundred and twenty five degrees fahrenheit.
Speaker 2 (05:07):
And it's very dry because there's no running water on
the surface and almost no humidity, so it's a very
dry place, basically a dry desert, cold dessert.
Speaker 1 (05:17):
Is the whole planet like that or only parts of it?
Is there any variation?
Speaker 2 (05:21):
Well, in terms of climate, it's pretty similar. I mean
yet equator. You can have sometimes actually above freezing a
couple of days, and it's colder of course at the poles,
but in general it's below freezing all over the planet,
plus very dry.
Speaker 1 (05:38):
So what would happen if I just teleport it to
Mars right now without any protection? What would happen to me?
Speaker 2 (05:44):
I think you would die pretty fast. I mean, first
of all, because there's no oxygen right, so you couldn't
breed anything. So I think that would kill you before
you froze to death. You will definitely not survive very long.
Speaker 1 (05:57):
I see now is the problem that there's no air
for that, the air that is there doesn't have oxygen or.
Speaker 2 (06:02):
Both both, so it's a low pressure environment. You would
need some kind of pressure suit, but you also would
need oxygen to bring with you to breed. Right the
atmosphere it's ninety five percent CO two and there's basically
no oxygen, so I don't remember the exact number, but
it's below one percent.
Speaker 1 (06:21):
What's Mars always like it is right now? Or did
it have a different history?
Speaker 2 (06:25):
So actually, if you go there and just take picture
of the surface, you actually see there's a lot of
feature indicating that we're flowing water at some point. So
there are water on Mars, but most of it is
either frozen at the poles, or just beneath the surface.
But at some point some of that water actually flowed
and it carved out like meandering river structures. You can
(06:48):
see deltas at the end of rivers into the lake.
Speaker 1 (06:52):
Wow, how long ago was that?
Speaker 2 (06:54):
This was a long time ago, so maybe aund four
billion years ago, so very early in the story of Mars.
Speaker 1 (07:01):
So four billion years ago, if you went to Mars,
you would see lakes.
Speaker 2 (07:05):
And rivers, yeah, presumably.
Speaker 1 (07:07):
And clouds and brain yeah. Oh what about the atmosphere?
Was it always one percent or was it different?
Speaker 3 (07:15):
No?
Speaker 2 (07:15):
So it's believed that the atmosphere were thicker, and this
is one of the reasons people think there's no water now,
is because the atmosphere creates pressure, right, and the pressure
makes the water be able to be liquid and not frozen.
So what people think is that there was a thicker atmosphere,
but that disappeared quite early in the history of Mars.
(07:36):
And when the atmosphere disappeared, the liquid water also froze.
Speaker 1 (07:41):
Oh, so it's due to the lack of atmosphere that disappeared.
Do we know what happened to the atmosphere? Why did
it go away?
Speaker 2 (07:49):
So this is also one big research topic about Mars,
and one of the reasons is there's no magnetic field,
and also Mars has less gravity they hold atmosphere.
Speaker 1 (08:01):
Okay, so it sounds like Earth and Mars were sort
of like twins at the beginning. I mean they were
very similar, rocky, there were lakes, there was water, there's
a thick atmosphere. But now Earth it's super different than Mars.
Speaker 2 (08:13):
Yes, so that makes it also very interesting. One is
teeming with life and you have the oceans a lot
of life, but the other one is like a dry desert.
Do you also have venos Actually, oh right, Venus, which
is almost the opposite because they have too much atmosphere
and it's very warm. Instead, it's covered by that thick case,
(08:35):
so it's hard to serve the surface and if you
try to land something, it kind of dies within a
couple of minutes because it's the heat is so high. Wow.
Speaker 1 (08:44):
So it's like there were triplets. They're all like the
same and they all took different paths.
Speaker 3 (08:48):
Yeah, I see.
Speaker 1 (08:50):
Okay, So there's a lot of talk now about going
to Mars, maybe establishing a colony there, exploring it. Is
it a place where humans could live? Are there resources there?
For us to live out the land or do we
have to bring everything with us like a camping trip.
Speaker 2 (09:06):
So there is a lot of research going into city
to resource utilizations. This is like using stuff on ground.
There are some resources. For example, you could take the
CEO two and then split that and make O.
Speaker 1 (09:21):
Two and so we have that technology to turn COE
two back into oxygen.
Speaker 2 (09:25):
Yes, hopefully we'll make some way to make oxygen so
you can breathe, and then we would have to make
food and also shelter. So one of the big problems
because we don't have that atmosphere is radiation. So the
radiation level on Mars is much higher than on Earth.
So one thing if we go there is to build
(09:46):
a shelter that you would maybe be able to manufactures,
although there's rock materi lying on the surface like a
dome to protect from radiation.
Speaker 1 (09:56):
Like, you couldn't just rely on your suit or a
camping tent. You need a thick wall to protect you.
Speaker 2 (10:03):
Yeah, maybe you could go there and stay for a
shorter time in some like inflatable type of habitat, but
then if you want to stay longer, you would probably
need to build some type of thicker like a dome.
Speaker 1 (10:15):
I see.
Speaker 2 (10:16):
Another thing people are thinking about. So there seems to
be caves, so you would be able to, you know,
live in a cave or something, because then you would
have automatically that prediction.
Speaker 1 (10:28):
I see, But then you might run into Martian bears.
Speaker 2 (10:31):
Well I don't think.
Speaker 1 (10:32):
So, okay. The last thing I talked to you, doctor
Sillystorm about was whether we could grow food on Mars
right now? Okay, so maybe we have energy shelter oxygen there.
What about food? Is there is there a possibility to
grow food there?
Speaker 2 (10:51):
There've been some scientific tests where they kind of grow
things and Martian analog soils, and it seems possible. One
problem is that there's toxic things in the Martian soil
that's not very good. There's type of salt called percurates,
which is quite common on Mars, that is not very
(11:13):
beneficial for the growth. You need to add like nitigen phosphorus,
which may not be abundant and not I mean, the
sun is also less strong on Mars because we're further away,
so you need to have netlives or something to get
the photosynthesis. You have plenty of seal too, so that's
not a problem.
Speaker 1 (11:35):
Okay, to recap. Mars is not the dream destination some
movies make it out to be. In fact, it seems
pretty dangerous to live there. It's freezing cold. There's very
little air or oxygen while the water is frozen at
the poles. You can't really grow food there. You need
to wear a pressurized suit the whole time, and most
(11:57):
likely you have to live in a cave that's not
peaceful or relaxing at all. Now, there is something that
serious scientists think we can do to make Mars a
nicer place to live, and that is terraforming. So when
we come back, we'll talk to an expert about what
(12:18):
that is and whether it could ever work. Don't go anywhere,
we'll be right back and we're back. Okay, we learned
that Mars is not a cozy place. It's not nearly
(12:39):
as bad as the other planets in our Solar System,
but still living there would be like living in Antarctica,
except there's almost no air to breathe. There's a ton
of radiation, and if you took off your spacesuit you'd die.
This is why people have talked about terraforming Mars, which
is to change at mosphere. Now to fill us in
(13:02):
on how that works and whether it's possible reached out
to a Mars terrorforming expert. Doctor Francois Forge is an
astrophysicist who has worked on many space missions for NASA
and the European Space Agency. Here's how he describes what
he does.
Speaker 3 (13:20):
So, I'm a planetary scientist. I study mostly the atmosphere
on other planets and in particular Mars. I've been working
on many a space mission on the ground and in orbit.
I'm among the person who does climate modeling, the same
thing you do on the Ears to do climate prediction,
but we apply these models to other planet, in particular
(13:40):
planet Mars.
Speaker 1 (13:41):
The start off, what is it like in Mars if
we were together there?
Speaker 3 (13:45):
And mass today has many similarities with the Ears because
the length of the day is twenty four hours and
forty minutes. You have seasons just like on the Earth.
Because the tilts of the axis of rotation is about
the same that on Earths. As the consequence, you have
a low pressure system jet. When you have moonsunjets, you
have many similities. Of course, it's different because it's much drier,
(14:09):
the pressure is very low. You have on average six
hundred and ten million bars, but that's one hundred time
less than on the Earth, so it can be very
cold that it deserts like planet.
Speaker 1 (14:22):
Next, I ask him to describe what terraforming is. Now,
you wrote a paper about this idea of terraforming bars,
can you explain to us what terraforming is.
Speaker 3 (14:34):
Okay? Terraforming is to modify your environment at the planetary
scale so that you can either make life easier for humans,
or you can also a low life, typically terrestrial life,
to grow and develop there, and ultimately you can even
imagine completely adapting it to a human life.
Speaker 1 (15:00):
According to doctor Farge, there are three levels of terraforming.
It's sort of like when you go to the spa
and you get a choice of three levels of treatment.
You can get just a bag massage, or you can
get the full body massage, or you can get the
full body massage plus the modbath, the hot stones and
those little cucumbers that cover your eyes, or you can
(15:23):
think of it like levels in a video game. They're
all terraforming, but each level gets harder and trickier. Here's
how doctor Farge describes each level.
Speaker 3 (15:34):
One is to directly raise the pressure so that you
can walk around without a spacesuit, a seconetist who adapts
mass to some form of terroristial life, and finally to
adapt mass for humans to be just like the Earth.
Speaker 1 (15:49):
Interesting. There's three levels of terraforming.
Speaker 3 (15:52):
Yeah, and there are side options.
Speaker 1 (15:54):
Now we'll get into each of these levels, but first
I was curious about where the side came from.
Speaker 3 (16:02):
This is not a new idea. It's something you can
find in many science fiction books, movies, even games. It's
quite a popular concept. Ellen Musk has been popularizing it
because he wants to do that. But in reality, if
you look at the technical and scientific literature, there are
very very little studies, not many studies about that, so
(16:26):
you can become a specialist quite quickly. So the point
is to say that there have been some speculations, some
scientific studies in the seventies and the eighties. A key
scientific studies was published in nineteen ninety one by Chris McKay,
Riot Tune, and Jim Casting. They were all together at
(16:47):
the Nazaims Research Center. I was there just after this,
so I know them well. And this is really something
that is at the basis of many of the speculation
that you can read today in the pular literature and
stuff like that, and lots of the concept that I
will describe today are in fact described very well in
this interesting paper.
Speaker 1 (17:08):
Okay, to start, here's level one of terraforming Mars, and
that is to simply raise the atmospheric pressure.
Speaker 2 (17:17):
There.
Speaker 1 (17:17):
As mentioned before, the air on Mars is one hundred
times thinner than it is on Earth, so all you
have to do is make more air.
Speaker 3 (17:29):
So now let me go to the first step, that
is to raise the atmospheric pressure so that you can
live without a spacesuit. And the side effect of this
will be too allow to have liqid water on the
surface more easily.
Speaker 1 (17:41):
Can I just ask why does the low pressure require
you to use a space suit?
Speaker 3 (17:45):
Well, there are two reasons. The first one is the
fact that if you go to Mars right now, you
can't have liquid water at all because water will boil
at two three degrees celsius. That means that, for instance,
if you walk around you're a saliva will boil and
your blood will want to boil as well. At thirty
seven degrees you're well above the boiling point, so you're
(18:07):
like a pressure cooker. You don't want to do that.
Speaker 1 (18:12):
Yeah, not having your blood boil would be nice. The
second reason you need a pressure ized suit is that
at those low pressures there wouldn't be enough oxygen atoms
for your lungs to breathe, even if you wore a
pure oxygen mask. So clearly it would be nice to
raise the air pressure on Mars, But how would you
(18:34):
do that?
Speaker 3 (18:37):
So the conclusion you need a space suit today, and
if you don't want a space suit, you need to
find a way to raise the pressure of the atmosphere
on Mars up to at least one hundred twenty millibars
typically okay, and that's a lot because right now on
Mars you have six midi bars of mostly CO two.
(18:59):
So the question is how can you raise the pressure
up to one hundred and twenty million mars or even higher?
Speaker 2 (19:05):
Okay?
Speaker 3 (19:06):
So you need some gas. And they had this idea
that especially in the polar regions, there should be frozen
COEO two ready to be released. So they say that, mmm,
we think that if we can heat the pole, we
can sublime in other world, transform the seal to ice
(19:27):
into seal to gas sufficiently so that you increase the
amount of seal to gas.
Speaker 1 (19:35):
Okay. So one idea to raise the pressure on Mars
is to take all the CO two ice we see
in Mars' north and south poles, melt it so it
turns to gas, and fill up the atmosphere with it.
Now scientists think that you wouldn't have to melt all
that coeo to ice. That'd be like melting all the
(19:56):
ice in our north and south poles. You could do
it by triggering global warming.
Speaker 3 (20:04):
Seal two, by the way, is a greenhouse gas, so
if you increase the amount of gas, there could be
a runaway greenhouse effect in other worlds. You heat a
little bit the polese, it really is a little bit
of seal two s to hat the planets, and then
you have a runaway process that sublimes all the CO
two around and suddenly you have a very nice thick
(20:26):
atmosphere made of seal two.
Speaker 1 (20:29):
Yeah, what could go wrong? All right? So then how
do you get this global warming started? And this is
where things start to get a little science fictioning.
Speaker 3 (20:42):
On this basis you may have heard. All we have
to do is to initialize this, for instance, by using
mirrors to hit the poles of mass, and that could
trigger this runaway climate change that will suddenly transform mass.
Speaker 1 (21:00):
So one idea is to float mirrors in space around
Mars and point them so that they focus the light
from the Sun to the North or South poles, sort
of like a giant space magnifying glass. And from there
the ideas get even crazier.
Speaker 3 (21:20):
Some people have suggested that you could spread the I
don't know, very dark material on the cap and sudden
need will absorb the sola heat and go into this process.
If you know Ellen Musks, it goes around with a
T shirt where it's threetened nuke mass. And this idea
is that, okay, let's release the coal two frozen at
the poles by putting nuclear bombs and it will sudden
(21:43):
nut ones from MASSO.
Speaker 1 (21:47):
That's right. One idea is to paint the North and
South poles black so they absorb more heat, and the
other idea is to explode nuclear bombs to vaporize the
North and Sells poles. Like I said, what could go wrong?
But not all ideas are it this destructive. Another way
(22:08):
to cause global warming is to simply pollute the Martian atmosphere.
Speaker 3 (22:15):
A very popular weight that has been studied was to
make factories and create super efficient greenhouse gas. With the
fluoro carbon. For instance, you can make artificial greenhouse gas
that will really create a strong greenhouse effect with only
a few part per millions. So factories will be enough
(22:36):
to create that if you find the material to make them.
We could invent aerial salts metallic carrosalts with the form
of a needle that will be especially optimized to also
create a very efficient greenhouse effect.
Speaker 1 (22:53):
Okay, that's terraforming. Level one increasing the pressure so we
don't need spacesuits to walk around. Level two is having
life grow on Mars.
Speaker 3 (23:08):
Step two will be to have plants than life that
could survive on Mars, to adapt mass in a way
that you could imagine, have plants, algae, something living that
could survive and thrive on the surface. So some people
will find that exciting because you bring life to somewhere
(23:28):
else down on the Earth. Some people will be motivated
by the fact that plants will be a way to
modify an atmosphere. For instance, photosynthesis could transform CO two
into oxygen, and this is a way to transform Mars
in something more suitable for humans.
Speaker 1 (23:47):
That sounds great. Why doesn't that work?
Speaker 3 (23:51):
The reason is that life is very good as growing everywhere,
even if it's called one acidic whatever. But life requires
liquid water on the Earth is very simple. If there
is liquid water, you have life. Even if it's salty water,
if it's at minute ten degrees, if it's very hot
(24:11):
water at the bottom of the ocean at one hundreds. See,
it's okay. Life is happy. But you need liquid water.
If you are only ice, live stops. If you have
only water vapor, life stops. So the question is how
to get liquid water on Mars.
Speaker 1 (24:29):
Okay, this gets a little bit technical, but basically, because
Mars has low pressure and low temperature, water only really
exists as solid ice or vapor, which is a problem because,
as doctor for j said, life needs liquid water. So
you don't only have to raise the pressure in the atmosphere,
(24:51):
you also have to raise the temperature. There is good news, though.
Speaker 3 (24:57):
There have been studies that show that life simple. Life
like ALGs and even some plants can be happy with
the low pressure atmosphere. They don't need as high as
an atmospheric pressure than what I describe for human but
you need liquid water. And to have liquid water, the
absolute pressure must be about six point one meter bars.
Speaker 1 (25:20):
Okay for level two You don't need to raise the
pressure as much as in level one, but you do
need to raise the temperature, which you might have already
done if you trigger global warming to melt the CO
two in the North and South Poles. All right, when
we come back, we'll tackle the last level of terraforming Mars,
(25:42):
the boss level, which is making Mars just like Earth.
Don't go to another planet just yet. We'll be right back.
Welcome back. Okay, come to the boss level of terraforming Mars,
(26:04):
the ultimate treatment in our planetary spa many making Mars
just like Earth. And here the idea is not just
to make the pressure on Mars the same as on
Earth so you can walk around without a pressureized spacesuit,
or to make the temperature high enough to have liquid water.
This is going all the way.
Speaker 3 (26:27):
Step NUMBA three is really science fiction, but we've been
there since the beginning. So it's to give mass a
breathable atmosphere for humans. That will be the real terrorformation
that you can dream of in science fiction movies. You
go around, you walk around, just like in Star Wars,
all these planets.
Speaker 1 (26:49):
Imagine stepping out the door of your house on Mars.
You're not wearing a spacesuit. The temperature is a little nippy,
but not freezing. Above you, there are clouds blocking out
some of the harmful radiation coming from the sun, and
you take a deep breath. The air is a little dry,
(27:12):
but it's not boiling your saliva. And best of all,
it has oxygen, sweet, refreshing ly sustaining oxygen. And you
go for a nice run among the plants that are
growing on Mars, which is super fun because, as I said,
the gravity in Mars is forty percent what it is
(27:32):
on Earth, so it's like jumping around a bouncy castle.
Speaker 2 (27:36):
Whoo.
Speaker 1 (27:38):
That is the final level of transforming Mars. So what
would it take to get us there?
Speaker 3 (27:49):
So of course this means a lot of thing. First,
you need, as we discussed before, enough oxygen.
Speaker 1 (27:55):
Are there any ideas of where we would get all
this oxygen?
Speaker 3 (27:58):
No oxygen? No, No oxygen is easy because oxygen you
can get it from water. You can process water. You
have lots of water on Mars, have to admit so
water will be busy. You take water, you can electrolyize water,
so you can create oxygen. But you cannot be pure
oxygen because pure oxygen is dangerous. Everything tends to catch fire,
(28:20):
and it's very, very dangerous. It's a little toxic in
some way. If you breathe pure oxygen for some time,
you can have some disease, the Row and Smith effects
like that. It's inflammatory. In any case, you need to
dilute oxygen with another gas. Some on the Earth you
have nitrogen, but we don't have nitrogen on Mass.
Speaker 1 (28:40):
So the main problem in making Mars air breathable is
not oxygen. You could make it on Mars from water.
The problem is everything else that air needs to be breathable.
The air we breathe on Earth is twenty one percent oxygen.
The rest has to be something else, but it can't
be CO two, which is most of what's there on
(29:02):
Mars right now.
Speaker 3 (29:05):
You need to decrease the amount of many gases that
are toxic, like carbon monoxide carbon dioxide below a certain
level otherwise you have problems. You need to have less
than ten million bars of CO two typical clear and
less than point one million bars of carbon monoxide otherwise
you have big problems.
Speaker 1 (29:24):
When you are a human, okay, then you might think, well,
when you made oxygen from water, you also made H
two or hydrogen gas, right, could you use that to
dilute the oxygen?
Speaker 3 (29:40):
Well, no, because hydrogen and oxygen tends to react and
if you have sparkles, you explode, so you don't want
that either.
Speaker 1 (29:52):
All right, This brings us to what seems to be
the main problem with any of these terraforming plants, which
is that Mars doesn't have all the things we need.
If you're trying to pressurize the atmosphere or cause global
warming with CO two, there isn't enough of it on
Mars right now. All the missions we've sent there, like
(30:14):
the Mars Reconnaissance Orbiter, the Mars Global Surveyor or Mars
Odyssey have all found that there's not enough CO two,
either frozen in the North and South poles or absorbed
on the ground. And if you're trying to fill the
atmosphere with breathable air, you need a lot of nitrogen
or our gun, which Mars doesn't really have. And this
(30:37):
is where we run into the definition of what it
means for something to be possible. Some people say at
this point, well, you could bring the CO two from
Venus or Earth like ship it using rockets, or you
could go out to the asteroid belt, round up about
ten million comets and somehow get them to crash land
(30:59):
on Mars because comments have water and carbon monoxide. But
the sheer scale of these solutions start to get a
little ridiculous, or at least really really expensive, or expensive
is beyond the problem.
Speaker 3 (31:19):
In other words, you cannot do it with a technology
that we can imagine.
Speaker 2 (31:23):
Now.
Speaker 3 (31:24):
You may be able to do it if you use
one ten million commets that you move and bring to Mars,
but that's beyond our technology, completely beyond. We have no
energy to do that. Maybe in five hundred years we've
discover an infinite source of energies, but right now it's impossible.
That's my opinion. But it's a debate. If my colleague
(31:44):
Edwin Kite was here, it will scream and say, oh, Francois,
you're dead wrong. I will show you that you can
do it.
Speaker 1 (31:53):
And that's kind of where we're at. It's a debate.
Some people say it is technic possible to change Mars,
even if it takes an almost infinite amount of energy,
and we didn't even get to the ethical questions about
terraforming Mars. Some people argue that we shouldn't change Mars
(32:14):
that we should leave at pristine kind of like a
national park. And some say there could still be Martian
life there, maybe hidden under the surface, and that changing
Mars would be a huge act of genocide. So whether
we could or should terraform Mars, the answer seems to be,
(32:36):
maybe we should clean up our own planet first, all right.
To end this episode, I asked both our experts if
they would go to Mars.
Speaker 2 (32:46):
I tend to say no because if you go to Mars,
you have to commit two years at least to go there,
and I have a family and I don't want to
be away for like two years. I mean, it wouldn't
be cool to go to Mars. If you could go
there for a month, would be cool just to go
and go to a clear different environments.
Speaker 3 (33:05):
Me. I'm still a dreamer. I like astronauts, so I
will dream of going to Mass as an astronaut, but
to do expedition to Mars to explore and study Mass
and come back and leave Mass as clean as possible.
So I don't want to colonize Mars, and I don't
want to terraform Mars.
Speaker 1 (33:26):
Sef nasa Issa said doctor Frage. We needed to get
on this rocket tomorrow and go to Mars. You would go, Yes,
I will.
Speaker 3 (33:34):
I'm fond of such adventures.
Speaker 1 (33:39):
All right, thanks for joining us, See you next time
you've been listening to Science Stuff. Production of iHeartRadio written
and produced by me or Hm, edited by Rose Seguda,
executive producer Jerry Rowland, an audio engineer and mixer Kasey
peprom The same recording of Mars is credited to NASA
(33:59):
jeep Yale call Tech l A N L C N
E S C N R S and is E A supero.
Available on the NASA website at Science dot nasa dot gov,
and you can follow me on social media. Just search
for PhD comics and the name of your favorite platform.
Be sure to subscribe to Science Stuff on the Arheart
(34:19):
Radio app, Apple Podcasts, or wherever you get your podcasts,
and please tell your friends we'll be back next Wednesday
with another episode.
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