What killed Mars billions of years ago? How can we kickstart a warming trend to transform Mars to look like Earth? What kind of technology do we need, and how well will it work? I discuss these questions and more in today’s Ask a Spaceman!
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Mars stinks. I mean, it's not the worst planet in the solar system, but it's not exactly the best one, either. I mean, look, look, look, there's no air, OK? There's a little bit of air it it, but it's less than 1% of Earth's atmospheric pressure. And if I had less than 1% of the like, say, income that I have now or money that I have now, I would say I'd basically have no money. I think that's fair. In what air there is. It's entirely poisonous carbon dioxide. If you're a plant, that's not so bad. But I'm assuming most of you listening today are not plants, and so atmosphere made of entirely carbon dioxide is not the best thing for you. Speaking of poisons, this Martian soil is coated, soaked. You know whatever word you wanna use in perchlorate, which you might be more familiar with as an occasional source of rocket fuel, literal rocket fuel in the ground.
So if you ate Martian dust, you would just get a mouth full of rocket fuel. I mean, come on. Mars gets only 40% of the sunlight that the Earth does, so it's never ever gonna beat that sunny tropical day on a beach seaside resort kind of vibe. You're not getting that. It has 60% of the Earth's gravity. So even if you could live on Mars and hang out on Mars, you're gonna deal with constant low gravity and all the nasty biological issues that come along with it. Things that our astronauts are experiencing in microgravity situations. We don't even know if, say, like, uh, a fetus's spine will grow straight in the womb without our gravity and the strength of our gravity. Like that's a big unknown. And and I don't see anyone exactly lining up to be the first one to test that, and it's called Average Temperature on Mars is negative 81 F in Celsius.
That's also very, very cold. It's basically the same number maximum, though I mean, the absolute hottest day on Mars in the summer at the equator reaches somewhere around 70 F, like nice room temperature. OK, OK, I can take that, but then when you go in the winter in the poles, it plunges down to negative 220. That's quite a large range, folks. That's quite a big difference. It's like a 300 degrees difference between the equator and the poles. This is Mm. I mean, the poles are cold enough to freeze carbon dioxide into dry ice. In fact, most of the Southern polar ice cap is made of dry ice. There's frozen carbon dioxide, like everywhere just underneath the surface. It's, uh, and there's so much dust, like a lot of dust, and the dust has been blowing on Mars for billions of years. So it's been ground down to this fine talcum powder that just gets everywhere.
Like you. You just can't. You can't just brush it off because it sticks to you and it sticks to your clothing and sticks to everything. It's just gross like look at the pictures of the Mars Rovers and Landers that have been there a while. They're just coated in this nasty dust, and sometimes those dust storms can kick up, and they encircle the entire planet like plunge the entire world of Mars into a month long dust storm where you hardly ever see the sun. It's just, uh, Mars. But here's the thing. Mars used to be cool, man. And by cool, I mean hots and by hot, I mean kind of warm. It used to be rocking like 3 billion years ago. Mars was fantastic. It had oceans. It had rivers. It had streams. It had lakes. It had white, fluffy little clouds. It had balmy temperatures. It had a thick atmosphere, and it was able to have those temperatures back in the day. Billions of years ago, our sun was a lot weaker than it is today.
You know, slowly, over time, stars get brighter and hotter. So 3 billion years ago, our sun was smaller and weaker, and even with that Mars was rocking, it was warm enough to host liquid water on its surface. I mean, look, the recent Mars rover, the Perseverance Rover is at the Jazeera Crater. And the reason that site was selected because it's at a crater and it's actually at a flood plain where the crater was once filled with water. And then this is where the water spilled out. And so they're hunt, poking around where the imagine a giant crater full of water, a crater lake and then with with rivers and delta is the whole deal. Mars was a potential home for life. Mars was and continues to be in the habitable zone of the sun, the region of the sun where liquid water is possible, where it's not too hot, like mercury, where it just gets blown away and not too cold, like I don't know everybody else in the outer solar system where it just gets locked up in ice like Mars is in the habitable zone.
It can have liquid water, but it needs a thick atmosphere to have liquid water. 3 billion years ago, it did have a thick atmosphere, had tons of liquid water. It was great. And then things changed. See, Mars was doomed from the start, which is kind of tragic. 3, 3.5. 4 billion years ago, Mars wasn't all that different from Earth. If you looked at them like you would say, OK, like wet atmosphere, cloud pretty cool, right? But Mars was doomed because it was small, because for that kind of thick atmosphere, you need something to protect it. You need to protect it against the solar wind. The solar wind is this stream of high energy particles that are constantly emanating from the side. It's just along with every bit of sunlight. There are this stream of charged particles like electrons, mostly some protons. But they're high energy. They're just flood through the solar system. And you need to protect an atmosphere against that. Because high energy particles slamming into hapless innocent air molecules is gonna be bad news on Earth.
Our atmosphere is protected by our magnetic field. We have the strongest magnetic field in the inner solar system, one of the strongest magnetic fields in the entire solar system. We've got a really, really great magnetic field, and it's powered by our core. The the molten liquid iron core at the center of the Earth powers our magnetic field. When Mars was young, it had a molten core two. It had a magnetic field. It could protect its atmosphere against the solar wind. But because Mars was so small it cooled off the core, solidified it once it solidified the magnetic field shut off, and once the magnetic field shut off, the solar wind came blasting in. And over the course of I don't know, like 100 million years totally stripped away the Martian atmosphere. With the atmosphere gone, the air pressure dropped with the air pressure down the oceans literally boiled. Didn't matter about the temperature. Didn't matter that was in the habitable zone. Didn't matter that liquid water was possible with no atmosphere with no pressure, the oceans just boiled.
Mars dried up, Mars rusted. And it's looked like that for 3 billion years. So Mars used to be cool. It used to be awesome. And by cool, I mean, hot by hot. I mean, warm Mars used to be better. So stay with me here. If Mars was once awesome but isn't so awesome anymore. Is there any chance of a comeback of a reunion tour of bringing the gang back together for one last show? You know, back in the day, Mars knew how to rock and maybe it could rock again. Maybe we could increase the atmospheric pressure, give it some more air. Maybe we can make it warmer. Maybe we can get that frozen ice on the surface moving and grooving again. Maybe we could terraform Mars. We could make Mars be less like the Mars of today and more like the rock and Mars of the past, which looks a lot like earth today. Maybe we can transform Mars and and transforming Mars Terraforming Mars, uh, can have a bunch of different meanings. It can range anywhere from just making it a bit nicer and maybe having some decent vegetation, you know, like some lichen or maybe a shrub or two for accent all the way up to full fledged Earth.
Two point. Oh, with humans walking around in the park, Why do we want to terraform Mars? Well, arguments come from a few different directions for why we should even bother contemplating terraforming Mars. Argument number one is that Earth, is it? This is where we live. I mean, I know we have a few folks up in the international space station, but they're not exactly gonna be capable of repopulating us if we already wiped out. You know, there's some giant comet or asteroid or some disaster. If we blew up each other as we discovered our place in the universe, we really realized just how fragile we are here on the surface of this little planet. And like at any moment, something could go wrong. We could have a dinosaur event. And if we have humans living and working and self-sustaining on Mars, well, then you know, we got a backup option, which, which isn't the worst thing. And then they could come in and Tara, Free Tara, form of the earth and fix everything up, and we could be hunky dory again.
The other argument is that we're gonna be spending a lot of time on Mars someday, anyway, whether you personally like it or not. So we might as well make it decent to live there. Like if we're gonna set up Martian colonies if we're gonna have explorations on Mars, If we're gonna be doing things on Mars because we feel like doing things on Mars, we might as well fix up the place, make it a little bit more comfortable, make it a little bit happier, make it a little bit more warmer. You know, make it make it a little bit less miserable. If we're gonna spend time there anyway, you know, we can at least make it tolerable. So you don't need, say, a space suit or a pressure suit to be able to walk around on the surface. And maybe hopefully you could even make it livable. Maybe you just need an oxygen mask to walk outside. You know, and maybe we can start growing some plants on Mars. Like if we're gonna have people on Mars, we want it hopefully to be self sustaining so that they don't have to depend on the Earth and all of our wonderful manufactured goodies in plants and food.
And so maybe we can have some native Martian food. You know, we could have Martian grass and Martian cows. Maybe we could have Martian cheese. I'm just tossing that idea out there. You know, it is possible maybe to grow stuff on Mars, you know, once you wash away all those perchlorate, but the sunlight, you know, while low is comparable to like the high northern latitudes on the earth. So it's not impossible to grow crops. We grow crops in, like Finland or whatever, so we can do it on Mars. And also, if we have a thick atmosphere, we can reduce the the incidence of cancer for cosmic rays. There are these charged particles slamming in from all around the universe. We're protected by those cosmic rays by our atmosphere. Mars is not so lucky. So walking around the surface, you're just accumulating radiation damage. And if we have a thick atmosphere that it would just make things better. Another argument for terraforming Mars is we can restore it to its former glory. Remember, Mars is habitable. It remains in the habitable zone of our sun. It once was a home for life or a potential home for life.
And maybe it can be a potential home for life again. We're just We're not changing Mars. We're just bringing back Mars to the way it used to be. And then the last reason why we might want to tear for Mars is is probably the easiest plant to play this game with. Like if we want to start transforming planets and really go to town on this and and flexing our technological muscles like, have fun with Venus, that's all yours, Mercury. OK, if you want to give it a shot, I have no idea what you're gonna do there. But go ahead. And then you got the gas giants and the ice moons, like whatever. Like Mars is our best shot for playing these kinds of games. So all that sounds great. How exactly would we, you know, do this? You know, with actual real results, the good news is that we've had a lot of practice with warming up planets. Uh, we didn't exactly plan for this, but, uh, like, if if our goal is to say, warm up a planet, we've kind of been doing that for a couple of centuries.
Here on Earth, it turns out we've gotten good at warming up planets. You know, you just need a bunch of greenhouse gasses and we're good to go. So that's one thing we've learned from all this climate change stuff is to warm up other planets. Uh, you know, and at the same time, we're trying to, like, backpedal on that like, Whoa, whoa, whoa. Earth. Sorry we didn't mean it. We didn't know what we were doing. We're trying to cool this place off. We could just take, take export all that knowledge and expertise in warming up planets and and apply it to Mars. So, like we know the basic principles we can just use the greenhouse effect that we do on the earth. And the greenhouse effect is like you put a bunch of carbon in the atmosphere. The carbon lets the visible light of the sun through to hit the surface of the surface warms up. The surface emits infrared light, but then the carbon blocks that infrared light and it traps the heat and the whole thing warms up. So great we did it to the Earth without realizing it. Uh, now we can do it to Mars. So the first step is we need to bulk up that atmosphere, you know, at less than 1% of that atmospheric pressure of the earth that's not doing anyone any good.
And Mars is original atmosphere. It used to be super thick, but that's all been lost to space and is no longer available in the ground like there is exchange of air, uh, from the atmosphere, into the ground and back into the atmosphere like plate tectonics. Does this all the time with the earth. But that didn't happen on Mars. It may have never had plate tectonics, and so it just lost its atmosphere. So we can't just bring back the atmosphere. We have to artificially construct the atmosphere. The most obvious place to look for a source of carbon on Mars. To bulk up the atmosphere are the polar ice caps. There's lots of frozen water, lots of carbon dioxide, lots of greenhouse gasses. If you can somehow get the ices in the polar caps to to sublimate to turn into a gas, it would be atmospheric. And and so how do you do that? How do you get the ices there to sublimate and turn into a gas? You make it warm. Uh, well Well, how do How do plants get warm? Well, they get warm by having an atmosphere, and, um Oh, shoot.
There there's this, like, chicken and egg problem. In order to get an atmosphere on Mars, you need to warm up all the carbon that that's locked in ice and release it in the atmosphere that will thicken the atmosphere. Oh, but in order to warm up a planet, warm up the ice, you you need a thick atmosphere because, you know, greenhouse gasses in an atmosphere are really good at keeping planets warm. So So how do you start? How do you do this? How do you kick off this greenhouse cycle? Uh, the answer is, you do just do it one step at a time. You you bootstrap it, you give it some, you know, kicking the the behind, and then let the natural greenhouse cycle take it from there. Like I said, the polar caps are the most easily accessible and most obvious places to get at all those greenhouse gasses. The the water vapor, the carbon dioxide. And so why don't we focus on making the caps warm? Get that those greenhouse gasses up into the atmosphere, and then that will warm up the rest of the planet. And then, if there's any other water vapor carbon dioxide hanging out in the rest of Mars that will, once it warms up, they'll be released and get up in the atmosphere.
And then we're golden. So we've got a couple of options for warming up the polar ice caps. Option number one is to Sprinkle a bunch of dust on it. The caps right now are very, very shiny because you know they're frozen ice, so they reflect a lot of the light, a lot of sunlight that hits it. If we Sprinkle on a lot of dust, then that light will instead be absorbed, and it will warm up the ice and then release the ice into the atmosphere. Another option is to well, you know, literally build a giant mirror, put it in space and shine it on the polar ice cap. It sounds like some weird, dorky sci-fi villain plots, but it's a real proposal. It's just focused on the poles. You don't need to shine the spotlight all over Mars. You can just focus it on the polls and you're good and then the Poles will warm up. Mars will lose its polar caps because all that water and carbon dioxide will instead be in the atmosphere. And then, once the atmosphere is nice and thick, it will do a good job of warming up the planet, which will release more water and more carbon dioxide, which will warm up the planet back and forth, back and forth, back and forth.
You get this wonderful feedback loop that kicks in on average, you only need about four degrees of additional warmth global across the planet before the ice cap starts losing it themselves with no additional intervention. So if you can raise the Martian temperature by about four degrees, the ice caps will just naturally lose themselves, and this feedback cycle will kick in. But you knew there was a bit coming. Like I said, the current air pressure on Mars is around less than 1% of the earth. If you were to walk outside on Mars with no pressure suit, no space suit all the sweats and oils and et cetera, tears on your skin will just instantly boil, which does not sound like fun. It's essentially a vacuum you need about four times the air pressure in order to prevent that where you could walk outside without a pressure suit and your oils and sweat and tears, and all that won't instantly evaporate, or at least slow that down.
You need about 20 times that. You need it at about 20% of the Earth's air pressure to not need a pressure suit at all, because you can just walk outside and it would be warm enough and there would be enough pressure that you wouldn't suffer any like skin damage whatsoever. You would just need an oxygen mask. Depending on what the atmosphere is made of. It could be a just a pure oxygen mask if there's a lot of carbon dioxide in the atmosphere that is pretty poisonous to humans, and so you need that mask to be sealed. But then that, but basically that that's your goal. You need 20 times the current atmospheric pressure on Mars to make going outside, not a ridiculously cumbersome process. And so we can ask how much carbon dioxide, how much water vapor is locked in the polar ice caps if you sublimated all of the ice caps. If you turned every single molecule that is currently frozen in the ice caps into vapor, you would increase the air pressure on Mars to be about twice of what it is.
There's also a bunch of carbon locked up in the rocks of Mars, both as frozen carbon dioxide and also just bound up in the rocks themselves. If you strip mined all of Mars like you dug down to say, I don't know 1000 m and just dug it all up and got all the carbon out and put it in the atmosphere, you'd only get about another half a percent of the Earth's atmospheric pressure. That's it All. The sources of carbon on Mars that we know about at best can get you 2.5 times better than what the current atmospheric pressure is. 2.5 times you'll get to about 2.5% the air pressure of the earth, which is not enough to prevent all the liquids on your skin from boiling the moment you step foot outside temperature wise, with that kind of increased atmospheric pressure, it's gonna be about 10 degrees warmer on Mars, and that's it. This is a lot less than we previously thought, when when people have been thinking about terraforming Mars forever and we used to think there was a lot more carbon on Mars and that this would be an easy peasy process you like, build your giant space mirror, shoot it at the polar ice cap.
Wait a few decades, everything warms up, feedback cycle kicks in, and then you just wait a couple more centuries and boom, you're you're growing corn on Mars. Unfortunately, it doesn't look like that's gonna work. There simply isn't enough carbon on Mars to do this by itself, and you may just lose it all to the solar wind. Like as you're building this atmosphere, the solar wind is still blowing at your planet. And so for every molecule that you send up in the atmosphere, it might just get knocked out by the solar wind. Mars doesn't have very, very strong gravity. It's not very good at holding onto atmospheres, especially unprotected atmospheres. So you may end up just evaporating the polar ice caps and then ejecting all that material into space, which isn't doing anyone any good at all. Enter crazy ideas. One crazy idea is to boost this greenhouse cycle feedback loop by slamming ammonia rich comets into Mars. You heard it here first. Like if if you go out to the outer solar system, you'll find a comet.
Comets are have a lot of ammonia in them. The idea is, you drag it over, slam it into Mars. Release all that ammonia into the atmosphere. Ammonia itself is a greenhouse gas. Yay! So it contributes to the warming. But then ultraviolet radiation from the sun hits the ammonia and disassociates it, and we get a bunch of nitrogen. And you know what? Nitrogen does a great job here on Earth of filling up our atmosphere. So you get it. It's like a two for one combo. You get the greenhouse gas effect of the ammonia, and then when it's done its job, you get a nice thick, steady, relatively inert atmosphere. Downside, though I do need to comment, is that nitrogen quickly escapes. It's a very, very light gas, and Mars isn't very. Won't be very good ever at holding onto nitrogen. But you know, that's that's a problem for future generations. Here's another idea. Remember all those nasty chlorofluorocarbons you know, the CF CS that were blasting a hole in our ozone layer? It's It's a destroyer of ozone, and it's a nasty greenhouse gas, which is a bad thing for Earth.
But a good thing for Mars like Mars could really use a boost of warming so you could build, like CFC factories on the surface of Mars and just have them running 24 7 just pumping out the noxious CF CS. I mean, you do have to like mine materials from the Martian surface. Um, calculations have shown that if you took our current extraction efforts here on Earth had our current like mining and manufacturing and CFC emitting capabilities, that we have the earth and you simply exported to Mars. If Mars was already warm, you could maintain it by pumping out this kind of pollution. On the other hand, that's not enough to, like kickstart this feedback process. Another crazy idea is to import hydrocarbons like you, like you go to the outer planets and scoop up some really, really thick like you can't just, like toss hydrogen and helium on Mars. It's way too small to hold on to elements like that. But if you go to, say Titan and scoop up its methane and ethane atmosphere, those are pretty thick molecules.
Those are pretty heavy weights. Uh, and you can bring them over to Mars, dump them on Mars, and they will likely stick around. If you want a methane atmosphere on Mars, this is a good way to do it. If you were imagining something else Well, this is gonna be a little bit challenging. Speaking of challenges, by far by far, the biggest challenge IRA hinted at this was that dang solar wind. Whatever crazy solution you use if you start melting the ice caps. If you start dumping comets, if you start pumping out CF CS. If you start scooping up Titan's atmosphere and pouring it on Mars, you need to protect that atmosphere or all your work will be for nothing. It'll just go to waste because you'll put air in the atmosphere and it'll just get blown away by the solar wind. You need a magnetic field. If you want this crazy terraforming plan to work, you need to boost Mars's magnetic field. You can't restore the core. It's solidified so you can't kickstart that dynamo again. So you have to artificially create this magnetic field.
We have to build it ourselves. One idea is to place a gigantic and I mean gigantic electromagnet in space between the sun and Mars orbiting the sun at the same rate that Mars orbits the sun. And this creates like a giant magnetic deflector dish or field. And so, as the solar wind heads towards Mars, it bounces off of this magnetic field and ends up going around Mars so you can protect that atmosphere. Another trick you can do is to build a giant equator circling electrical circuit on Mars, just like a just just run that wire Just, you know, go to Home Depot and grab the electrical wire and and just start running, build a giant loop around Mars, turn it on and boom, you get an instant magnetic field. This magnetic field though, has to be very, very strong, which means the electrical current has to be really, really strong. Strong electrical currents tend to melt their own wires, and so this would need to be super conducting.
So it has to be really, really cold. And this way there was distance is very, very low, so it doesn't heat up. But if you could, if you could build a superconducting wire that completely circled the equator of Mars and powered it up, you could build a magnetic field for Mars to protect its atmosphere. Another challenge that you may not have thought of is the question of Should we do it? Even if we have the technology to melt the caps, bring in some source of atmospheric material, protect it with a magnetic field? Should we? There's this huge question of the potential for life on Mars. 3 billion years ago, Mars looked a lot like the Earth. 3 billion years ago, Earth had life. Did Mars have life? We don't know. Does Mars currently have life? We don't think so, but we don't know. We honestly don't know. It's a potential home for life, and it was a potential home for life. If there is life on Mars, then certainly it's adapted to the Martian lifestyle now. And if we import the earth lifestyle, the earth vibes, that's not gonna be too friendly for the natives.
And that doesn't feel right. Another argument is that you know what? Mars is beautiful the way it is. Why do we need to turn it into an earth two point? Oh, why don't we just build underground build underneath the ice caps build in volcano? You know, just why do we have to transform Mars? Why don't we transform ourselves to live on Mars? Another argument is we're not done studying Mars. Even if this process takes centuries to play out. Well, we have more than centuries worth of scientific work to understand the history of Mars, the formation of the solar system, hunting for signs of past life. And if we start mucking up the place, we're gonna erase all that evidence of the history of Mars. So, you know, we want to preserve it so that we can continue studying it. Another argument I've come across is that no matter what, once we start this terraforming journey, we can't just like pick up. You know, a plant, basil, and just stick it in a Martian dirt and hope everything goes OK. We're gonna have to do some seriously tortured genetic work to get plants and animals to survive on Mars.
You know, with the low gravity, they reduced sunlight, that perchlorate. You know, even if we start this terraforming journey, we're gonna have to transform life like Mars is never going to look like an Earth. Two point. Oh, it might look like an earth 1.4. And so we're gonna have to adapt life here on Earth and like that, that seems like it might get very, very messy. And then the last thing is, What about terror forming earth? I mean, we're kind of doing that already. Unintentionally. But what if we, like, took our energies and made earth as beautiful as possible? Why should we invest centuries of work on this? If if we could just spend all that time and energy and money and just and just make our home halfway decent those questions assigned if we decide we're going to do it, is it even possible? And the answer I'm gonna give you is a good old classic ASA spaceman. Maybe you want greenhouse gasses that's gonna cost you, and the best way to pay is by going to patreon dot com slash PM.
Sutter. It is your contributions that keep this show going. I truly, truly appreciate it. I think all of the space cadets every month. For all of their generosity, that's patreon dot com slash PM Sutter. It's easier than going to Mars easier than terraforming Mars, that's for sure. But if you want greenhouse gasses, it's going to take work. They're simply not on Mars itself. Mars lost its atmosphere. It's gone, and there isn't enough stuff. There isn't enough greenhouse gasses on Mars currently to rebuild it, so you have to bring it in from somewhere, even if you wanted to give it a shot of melting the poles, like with your giant space mirror. That sounds cool, but that giant space mirror has to be giant. It has to be like 100 kilometers across, and if it even if it's super thin, it's gonna take like 200,000 tons of aluminum. Where do you get the aluminum? Where do we get 200,000 tons of aluminum we? We certainly can't launch it from the earth. We'll have to mine it. Where do you mine it in space?
Do you go to asteroids? Do you bring it over to Mars? You wanna crash some comets into Mars for their water, for their ammonia for their nitrogen? Great. Uh, right now, the best we can do is send piano sized spacecraft out of the solar system. If we're really, really clever and work really hard, we can send orbiters to, say Jupiter and Saturn. But to go out to where the Comets are and then bring them back, that takes an enormous amount of energy. It would involve sending no joke nuclear reactors out to the Comets. And then you attach the nuclear reactor to the comet and you heat it up. And then, as it's heating up, some of the ammonia from the comet itself, uh, expels into space. You use that as a propellant. Speaking of nuclear power, if you want those chlorofluorocarbons, you know you you got mine. The Martian dirt each plant would require, like its own nuclear power source, and you would need hundreds of them just to maintain the Martian atmosphere and not even build it. You want that super giant magnetic field?
You want that electrical superconductor girdling mars? Well, that requires rare minerals. Hard to say exactly how much, but you might need to mine as much as 10% of the entire volume of Mars in order to build that superconductor. So you need to destroy 10% of Mars. And that's not even talking about a breathable atmosphere. You want oxygen? You actually want to walk on the Martian surface without, um, a mask. Good luck. There is oxygen buried in the dirt, like in the form of nitrates, just like there's oxygen buried in the dirt of Earth. But to free it to liberate, it requires energy to make a breathable atmosphere with the same amount of oxygen that the Earth has. You need to use about 250,000 terawatt years of energy. That's about 15,000 times more. Energy, then, is consumed by the entire human race every year. Terraforming Mars is not impossible.
You know, there's no like law of physics. There's no rule of the universe that says we can't and never can, Like I'm sorry you can't terraform Mars because you know it. It violates the laws of physics. No, it's just really, really, really, really hard. It's gonna take centuries at a minimum to build the magnetic field, to import atmospheric gasses, to melt the poles, to soak the planet in greenhouse gasses to make it warm. And if you end up evaporating all the poles and putting in the atmosphere, well, now, if you want water, you need to bring in the water, so you need like more comets. If you want those comets, you have to send missions out to the outer solar system, like involving nuclear reactors. You need to haul those comments back, like all that's possible with sufficient technology. We do not have that technology. We only close even thinking about dreaming about that technology. It takes hundreds of billions of dollars. It or it will take hundreds of billions of dollars just to send a single crew to Mars in the next few decades if we can even do it in the next few decades.
Right now, terraforming Mars is more sci-fi than sci fact, and, well, it's fun to speculate. I wouldn't hold my breath, get it? It's it's It's a marsh joke never mind, thanks to Jocelyn H on email Jerry on email Carrie G on Facebook at Rick Winterfell on Twitter, Tom saw S on email. Cheyenne S on Facebook and at Paper Monster 12 on Twitter For the questions that led to today's episode and please go to patreon dot com slash PM Sutter to keep supporting the show I'd like to thank my top patreon contributors this month. Matthew K, Justin Z, Justin G, Cavia Duncan M Coy D, Barbara Kay No Dude Robert H, Robert MNH, Andrew Friel, Cameron Now NAIA aone, Tom B, Scott M and Rob H. I can't thank you enough, and so I will try my best to thank you more and more every single day. I really do appreciate it. Hashtag ask a spaceman. Ask us spaceman at gmail dot com. Ask us spaceman dot com You know what to do. Follow me on all social channels at Paul Matt Sutter and I will see you next time for more complete knowledge of time and space