How Do You Science | Meet a Planetary Scientist (Will we ever live on Mars? Are aliens real?)

Today I'm talking with Julie Ménard, a planetary scientist at Washington State University. She told me about the terrestrial planets in our solar system, how we're about to visit Mars—and could even set up a station there someday, and the possibility of life in our solar system and beyond.

• See what NASA says about sending humans to mars
• Learn more about NASA's Gateway, the first space station around the moon
• Check out the planets in our solar system
• Find out how we're searching for life on other planets

 As always, submit burning questions at askdruniverse.wsu.edu.  Who knows where your questions will take us next.

Transcript

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Dr. Universe: Hey friends, I'm Doctor Universe, and if you're anything like me, you've got lots of big questions about our world. Today I'm talking with Julie Menard, a planetary scientist at Washington State University. 

She told me about some of the planets in our solar system and how we're about to send astronauts back to the moon and eventually to Mars. We talked about what that would be like and whether we can expect to meet extraterrestrial life out there someday. 

I can't wait for you to hear all about it. Let's get started.

So you are a planetary scientist?

Julie Menard: That's correct.

Dr. Universe: What does that mean?

Julie Menard: I'm interested in understanding how planets form and how they evolve through time, so how they end up looking so different from one another. So if you look at Mercury, if you look at the Earth, if you look at Mars, if you look at Jupiter, they look completely different. 

So I'm interested in how that happens in my research work, which I haven't done in a while because I'm in a teaching position. I would use data from satellites in orbit around planets and then map that, I guess, on the planet and try to see what's going on on the surface, what's going on on the inside of the planet, and try to better understand the differences there and to see how much information we can glean from satellite data to figure out if a planet is active today, what kind of activity we're going to find at the surface, things like that.

Dr. Universe: Did you only study planets in our solar system?

Julie Menard: I only studied the terrestrial planets in our solar system and the moon. So I did Mercury, Venus, Earth, Mars, and the moon.

Dr. Universe: What made you pick the terrestrial ones?

Julie Menard: They have an easy-to-see surface, which made it a lot easier to look at the surface and then the inside of the planet, and we have more data from spacecraft than for any other world. 

There's only been one spacecraft in orbit around Mercury at this time, so there's not a whole lot of information from Mercury. But for Mars, we have a lot. For the moon, we have a lot. For Venus, we have a good amount, just not quite as much either.

Dr. Universe: Do you have a favorite planet?

Julie Menard: I kind of go back and forth on that. So I used to have Neptune as my favorite because I just love the color. The shade of blue of Neptune is just very peaceful to me. But these days, I guess I really like Mars because there's, I think, a real possibility that within the next several decades, we're going to see a human on the surface of Mars.

Dr. Universe: Can you say more about that? Like, what does that look like? What does that mean to have a person on the surface of Mars?

Julie Menard: So there's the Artemis two mission that is scheduled to go in orbit around the moon in the next couple of months. So this is coming up. And then after that, Artemis three is going to send astronauts to the surface of the moon. And so this is kind of a proof of concept and getting to know what it's like to survive on the surface of the moon for longer periods of time. And then after that, the goal is to do something similar with Mars and sending people to the surface of Mars.

So one of the advantages of having people, as opposed to a rover, which is basically a big car that does science experiments at the surface of Mars, is that it's a lot faster to get the information from a human, and there is a dexterity and a thought process that we have instantly that we can't get from a rover. It's a lot easier to know if a rock is interesting if it's in your hand or on the ground but in front of you rather than on a computer screen. And so there is a real value to having an actual person there.

Dr. Universe: When I'm imagining an astronaut going to Mars, should I be picturing them living in the spacecraft and visiting the surface, or would they be staying on the surface somehow?

Julie Menard: So I think that the current plans, if I remember correctly, would be more that they would be at the surface and probably setting up kind of a campsite, but it would have to be pretty solid because you can't survive on the surface of Mars without a spacesuit. The atmospheric pressure is okay, but the composition of the atmosphere is way too high in CO2, so we cannot breathe that. And it's also very, very cold. 

So we need some type of enclosure to protect the astronauts there. The current plan would be to build a base, and then people would live there and then put on their astronaut suit to go outside to run experiments, pick samples, and so on.

Dr. Universe: Holy smokes, that's really exciting.

Julie Menard: The moon is kind of a stepping stone toward Mars. And so that Artemis mission that I was talking about, currently there are, on Earth, building pieces of a space station, which is called the Gateway. 

That's going to be built and placed in orbit around the moon, where, in the next several decades, the goal of that is that we can send astronauts from Earth to the Gateway, that space station, and then they will go from the Gateway to the surface of the moon for shorter periods of time, run their experiments, pick up their samples, and then come back up to the Gateway and then maybe go back to the surface here and there and then go back to Earth. 

And that's in the real near future because, again, pieces of the Gateway are being built right now in the world.

Dr. Universe: Wow.

Julie Menard: Yeah. I'm really excited for this mission.

Dr. Universe: Do you think that a time will come in the future where regular people are living on Mars and getting born on Mars and going to school on Mars and doing all of that stuff?

Julie Menard: So that's an ethical question that folks are still pondering. If somebody volunteers to go to Mars and then they're selected and they go to Mars and they spend the rest of their life on Mars, that was their decision. Great. But as far as I know, NASA and other space agencies do not like the idea of, let's say, someone being born there and not having the possibility of making their own decision. So, ethically speaking, it's at best a gray area.

In terms of practicality, there is the idea of establishing a town on Mars to have people work there, kind of like we have in Antarctica, a station with people working there. One of the difficulties is it takes just a few months to send something to Mars. But that only happens every two years. That means that if we send someone to Mars, they're going to be there for at least two years.

Dr. Universe: Wow. It's like the Oregon Trail or something.

Julie Menard: For a trip to the moon, you can come home in a week and a half. It's not much of a time commitment, but it's a whole lot of other types of commitments. For Mars, only very specific people would be capable of handling that.

I guess on the one hand, I want it to be realistic and happen. On the other hand, I'm not completely convinced because Mars is not really friendly to humans because it's so cold and there's so much carbon dioxide in the atmosphere. We can't survive there unless we're in something that we built that is going to have the right composition and the atmosphere, so the oxygen to begin with, and the right temperature. 

I don't know how realistic it is to build something big enough for this, to build a city. 

Dr. Universe: It would be like a city that was like a building, like enclosed, like a bubble.

Julie Menard: Yeah, pretty much.

So some people talk about terraforming Mars. So we take Mars as it is right now, which is really, really cold, and we start planting trees so that the oxygen in the atmosphere builds up. But it's not that simple. And even if we went all in on terraforming, it would still take hundreds of years.

And we also actually have a treaty that was signed, I want to say, in the sixties. There's a treaty that was signed by the nations that had space agencies at the time that says that we're not going to mess up other worlds, so we're not going to go plant something on another planet because that would modify it. That treaty is being trampled on quite a bit, but it's still there.

With the way that the climate is changing on Earth, there's a point where it's going to be pretty unpleasant to live here. In some ways, that's a motivator to figure out ways to live somewhere else, whether it's a station in orbit around the Earth or just full-on another planet. 

If we're talking one hundred years, I personally don't think that it's realistic. If we're talking a thousand, what do I know? We went from the first plane to having a spacecraft outside of the solar system in just several decades.

Dr. Universe: So changing gears ever so slightly to the other entities that could have an opinion on this, do you think that there is life out there off of Earth?

Julie Menard: Yes, I think so.

Dr. Universe: Do you think there's intelligent life?

Julie Menard: That I don't know. I want to say yes because, statistically speaking, if we look at the number of worlds in our solar system, the number of worlds around other stars in our galaxy alone, and then everywhere else in the universe, it would be really, really surprising if life was only found on Earth. 

In terms of finding life elsewhere in the solar system, I do not expect intelligent life. I expect life, but not intelligent life. In other systems, yes, I would expect intelligent life.

Dr. Universe: So when you say not intelligent life, we're thinking like bacteria. Things like that.

Julie Menard: Yeah, exactly. Just a few cells. But maybe something out there a little farther away.

Dr. Universe: Do you think they've ever visited us?

Julie Menard: I personally don't think so, but I don't think there's a real way to know. I mean, some folks have stories, right?

Dr. Universe: I'm curious if you always knew that you wanted to be a scientist in general and a planetary scientist specifically?

Julie Menard: Uh, no. And no. I wanted to be an artist, and then I wanted to be a surgeon, and then I wanted to be a climatologist. And then I wanted to be a planetary scientist.

Dr. Universe: Wow. So how old were you when you decided on planetary science?

Julie Menard: I think it was twenty-three or twenty-four. I was doing a geology degree, an undergrad in France, and I decided to do study abroad for my last year. And I came to the US, and for my program, I had to take a physics class, and I did not want to take a physics class. 

So I took an astrophysics class, which was physics, but it sounded more cool to me, and I loved it. It was a lot of work. Some of it was a little painful, but it was so interesting to me.

At the end of that year, I got my degree, my bachelor's, and then I decided to start a master's in France in planetary science as a result. But it got me to really think about planets and our solar system, and I decided that I wanted to work in that field. And so that's why I did planetary science as opposed to astrophysics, where planetary science is more of the geology side of things rather than the physics side of things.

Dr. Universe: What's the best part of your job?

Julie Menard: Interacting with the students. I love talking to the students, and my absolute top favorite is when I'm explaining something to them and they don't quite understand it, and we talk about it for a while. And then when they have that aha moment where they get it, I love that.

Dr. Universe: Is there a most amazing or most surprising or most weird thing that you know about planets or space?

Julie Menard: So Neptune is the planet that is furthest away from us. It is the outermost planet in our solar system. In orbit around Neptune, there's a moon called Triton, and on Triton there are active volcanoes. So it's not the same type of volcanoes as we have on Earth because it's super cold there, but it's still volcanoes, right? And I find that amazing.

Dr. Universe: Does, like, lava come out of them?

Julie Menard: I think it's geysers. So it's cryovolcanoes where it's water that is erupting out of a frozen surface.

Dr. Universe: Wow. Like an ice volcano.

Julie Menard: Yeah.

Dr. Universe: On Mars, there's Olympus Mons, which is the largest volcano not only on Mars but, as far as we know, in the entire solar system. It's way larger than Mauna Loa, which is the largest volcano on Earth. It's taller than the Himalayas, which is the tallest mountain on Earth.

The atmosphere of Mars is not very thick. It's thick enough that when you land something on Mars, you need a parachute, but it's much thinner than on Earth. And because Olympus Mons is so tall, if you were to stand on top of Olympus Mons, you would technically be in space. You wouldn't be in the atmosphere of Mars anymore. 

And as far as we can tell, it is not currently active. However, we know that there is some activity going on inside of Mars, so it hasn't been active in a long time, but that doesn't mean that it's completely dead either. I find it really interesting because Mars is only about half of the size of the Earth, and it has a volcano that is larger than anything we have on Earth.

Dr. Universe: Would there be lava coming out of that if it became active?

Julie Menard: Yeah, probably some lava.

Dr. Universe: Oh my gosh, can you imagine if we spent all that time to, like, build a life on Mars and then the biggest volcano ever is there?

So we need to build a station or a little town on Mars that's, like, lava-proof.

Julie Menard: Yes. Or far enough from Olympus Mons or from the other volcanoes. There's a few other volcanoes at the surface. We want to avoid those. But you also want to be near the poles because that's where the frozen water is. We kind of need water. So you want to be nearby.

We think that Mars used to look a lot like Earth, or it probably used to have continents and oceans. It's been losing a good portion of its atmosphere when the magnetic field of the planet just died out. 

So it's basically this big, big magnet. We have one inside of the Earth where the core of the Earth is metal that is whooshing around, and that is forming this big magnet. It extends further out than the planet, and so that protects us from solar rays. Mars used to have a magnetic field, but it stopped. We don't know why. That's actually something that folks are researching. 

And so when the magnetic field on Mars stopped, the atmosphere was no longer protected from solar rays. It is about twice as far from the sun as we are, and so the atmosphere is not getting attacked quite as much as our atmosphere would get, but still quite a bit. And so it's been losing its atmosphere ever since.

Dr. Universe: How long did that take for it to become, like, barren?

Julie Menard: It was probably somewhat fast, honestly, because it's losing atmosphere at the rate of several tons per day.

Dr. Universe: Wow.

Julie Menard: So when the magnetic field on Mars stopped working, the atmosphere was no longer protected. And so what that means is that the temperature went way down, the atmosphere wasn't quite as thick, so the pressure at the surface changed. And as a result, most, if not all, of the water ended up frozen.

 And so there are polar ice caps on Mars at both poles. There's a good amount of water, but there's also a good amount of CO2 ice. And there's also water ice within the ground, which is called permafrost.

And so people looked at the size of the ice caps, the water ice portion of it, and mapped out, if this was all liquid water, what would that represent? And calculations have shown that that would be enough to fill oceans, maybe not as deep as on Earth, but still a solid amount.

Dr. Universe: How long ago would that have been?

Julie Menard: Probably two to three billion years ago.

Dr. Universe: So way before people?

Julie Menard: Yes.

Dr. Universe: Do we think that there was ever life on Mars?

Julie Menard: Yes. One of the main things that is included in most of the spacecraft, rovers, and so on going to Mars is search for life, search for past life, to be exact. We don't expect to find anything that is currently alive on Mars, but we hope to find fossils of past life. We've been looking for this for a while.

There was, I can't remember which rover it was, but there was one that took a picture of something that kind of looked like a worm. And at first, people started to publish this saying, we found worms on Mars. I mean, the dead ones, fossils of worms. But it could also have been something else. So, so far, we've seen that several times where there's a discovery that could be from a living organism, it could be a fossil, or it could be produced by a living organism, but we don't have the one hundred percent proof that it is.

Panspermia is the idea that the building blocks for life, the nucleic acids, would have come from somewhere else. And the idea is that they could have been on comets or asteroids, and then those comets or asteroids would have impacted the Earth and the other planets while all the planets were forming. 

And so that's part of the idea of finding life elsewhere, is if life on Earth started because of that, then the likelihood of it doing the same on another world is really, really high.

Dr. Universe: That's all for this episode, friends. Big thanks to Julie Menard for teaching me so much about Mars. 

As always, if you've got a science question for me, you can submit it at askdryniverse.wsu.edu. That's A S K D R U N I V E R S E dot W S U dot E D U. 

Who knows where your questions will take us next.