Is Settling Mars Inevitable, Or An Impossibility? In The Case for Mars: The Plan to Settle the Red Planet and Why We Must, Robert Zubrin argues that America is more prepared to send astronauts to Mars today than we were to send astronauts to the Moon in 1961. And he thinks we should, despite considerable risk to potential colonists.

Is Settling Mars Inevitable, Or An Impossibility?

Is Settling Mars Inevitable, Or An Impossibility?

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In The Case for Mars: The Plan to Settle the Red Planet and Why We Must, Robert Zubrin argues that America is more prepared to send astronauts to Mars today than we were to send astronauts to the Moon in 1961. And he thinks we should, despite considerable risk to potential colonists.

IRA FLATOW, host: This is SCIENCE FRIDAY. I'm Ira Flatow. We're not going to the planet Mars anytime soon. President Obama suggested something like the mid-2030s as a target date, but for various reasons - the dangers of space travel, the price tag, more pressing problems on this planet - that trip to the Red Planet has been put on indefinite hold.

My next guest says that's a mistake. We can and should be able to make the trip by 2020, and he says that technology - technologically speaking, we're already closer to being able to send astronauts to Mars than we were to sending men to the moon back in 1961, when President Kennedy made his pronouncement.

But what about all the obstacles: radiation, length of the trip, the lack of gravity during the voyage and all the potential hazards to the astronauts? Robert Zubrin has solutions to every one of these problems, and he's not just thinking about exploratory scientific field trips, he envisions human colonies growing crops in Martian soil, making energy from the atmosphere, even evolving new cultures and dialects.

So what do you think? Would you volunteer as a colonist from Mars? Or are you happy to let NASA's Rovers, the robots, explore the Red Planet? Give us a call. Our number is 1-800-989-8255, 1-800-989-TALK. You can tweet us @scifri, @-S-C-I-F-R-I. Or you can go to our Facebook page or our website. Our home page is

Robert Zubrin is the author of "The Case for Mars: The Plan to Settle the Red Planet and Why We Must." He's also president of the Mars Society based in Golden, Colorado. He joins us from the studios of Colorado Public Radio. Welcome back to SCIENCE FRIDAY, Dr. Zubrin.

ROBERT ZUBRIN: Thanks for having me.

FLATOW: For all the skeptics out there - and you know there must be a lot of them, I want you to lay out the case of why we should go and overcoming the obstacles I just mentioned. First let me go - maybe I'll tick off the points, and you might be able to answer them. First of all, how about a rocket? Do we need to develop new rocketry to get us there?

ZUBRIN: We need a heavy-lift rocket, comparable to the Saturn 5 that we flew to send astronauts to the moon in the 1960s. We don't have such capability today, but certainly it's within our technology to create one.

FLATOW: And there were three of them lying on the ground the last times I looked, in various places, Saturn 5s. How long would it take us to get to Mars?

ZUBRIN: The one-way transfer time is six months, and then you are there for a year and a half exploring, then another six-month transit back. Six months is the standard rotation, you know, the crew on the Space Station.

FLATOW: And what part of Mars would be the best place to land?

ZUBRIN: Well, scientists debate that a lot. But some of the criteria are the following: You'd want it to be a low latitude that is not too far from the equator so you'd get a lot of sunlight and daylight and warmth. You want a low altitude so that the atmosphere is thicker, which makes it easier to use as a resource, which makes it easier to use parachutes to land, which gives you more shielding against cosmic rays.

You'd want it to be in a place where we've detected deposits of water in the soil, but that is a fairly broad number of places on Mars. You'd want it to be in a place where you're fairly close to a large variety of geological phenomena and sites of scientific interest.

Ideally, we'd like to be in a place where we are within drilling distance of subsurface water because if there's life on Mars today, that's where it is.

FLATOW: What about the people like Dr. Lawrence Krauss, who think this is too dangerous a mission, there's too much radiation on the way out there, that the people that would probably best go would be one-way passengers, and there would be probably a lot of people who would volunteer to do that?

ZUBRIN: Well, the idea of a one-way mission has been around. I think it has some validity not conceived of as a suicide mission but as a Plymouth Rock mission, a colonization mission. So you don't just send people to Mars and abandon them. You send people to Mars, and you follow them up the next mission opportunity with more people and more equipment, and you build up a settlement.

Life is a one-way trip, and one way to spend it is by going to Mars and starting a new branch of human civilization there.

FLATOW: And how many - so you're starting a colony, as you say, like in Plymouth Rock. How many missions, or how many - well, I'm going to use the word missions - would you send or start, and how many people on each mission would go?

ZUBRIN: Okay, well, okay, the initial mission - now the mission that I have designed is a two-way mission because I believe that if this is going to be done by the U.S. government, which is the likely prospect, at least for the medium term, it would be in fact a round-trip mission. And I would send a crew of four.

Two of the four would be people whose primary skills is that of mechanic - great fix-it people, handymen and women because really, the life of the crew depends upon the functioning of their equipment, and you really want to have two really good flight mechanics on this mission.

The other two would be primarily chosen for their skills as field scientists because we're going to Mars to explore. This is the intellectual payload of the mission. Now, the field scientists would be people who are not helpless around machinery, and the flight mechanics would be people who are not totally ignorant about geology and this sort of thing. They'd be cross-training. But those are the two primary skills that are really needed.

You might have one of those four be a person who perhaps has practiced medicine at some point in their life. All of them would be trained in first aid, but you wouldn't have anyone on the mission whose primary occupation was doctor because that is a skill that only comes into play in a contingency.

Similarly, why you'd have someone who was the mission commander, that would not be the only thing he does. He wouldn't just sit around in a bean-bag chair and tell other people to do things. He would be - or she - would be one of the other four active people and same with pilot, another skill that only is valuable for a very brief moment during the mission.

FLATOW: What about the criticism that says there's so much radiation in space, and during the trip, you would get so much that it would be a virtually lethal dose of radiation?

ZUBRIN: That's actually false. There's two kinds of radiation that can get you in interplanetary space. There's solar flares; there's cosmic rays. Solar flares could deliver a very large dose, but you can shield against solar flares by having a solar flare storm shelter onboard the ship, which you would use the provisions - the water and the food or the wastes can create a pantry storm shelter, which can mask out solar flares.

Cosmic rays you can't shield against, but there isn't that many of them, and it's only around 50 rem for every year you're in interplanetary space, which is about how long you would be in space on this mission: six months out, six months back.

That would represent about a one-percent risk of the crew getting cancer. And I have to say, you know, this keeps on being said again and again and again, but the crews on the International Space Station and on the Mir Space Station, they get a cosmic ray dose which is fully 50 percent that which a crew in interplanetary space would get.

Of course, the Earth's magnetic field does not mask out cosmic rays. Their dose rate is down by a factor of two because the Earth blocks out half the sky, but nevertheless, we've had people on orbit for very long periods of time, and as a result, there are six cosmonauts and four astronauts who have already taken cosmic ray doses comparable to or greater than they would have gotten on a round-trip to Mars, and none of them have developed any radiological health effects at all.

FLATOW: And once you got there, would you then be able to use whatever you find there and build whatever you need from the resources on the planet, the water, the soil, things like that? How would you build the shelters?

ZUBRIN: Okay, well, that is the craft to be developed. Now, in my Mars mission plan, the very first mission, we make use of the most obvious Martian resource, which is its atmosphere, to use it as feed stock for making fuel and oxygen to power both the return vehicle and also ground vehicles.

The - going beyond that, we'd want to extract water from the soil. The Mars Odyssey orbiter has detected large regions of Mars in the equator, equatorial regions, that are six percent water by weight, in the high latitudes up to 60 percent water by weight.

At my company, we've built a machine that basically takes Mars soil simulant that's six percent water by weight, and we just baked the water out. It's not a terribly complicated idea. But the crews on Mars are going to want to do that. We're going to want to access Martian water.

Then we're going to want to learn how to grow crops on Mars using Martian water and Martian soil, Martian sunlight, Martian gravity to develop the craft of growing food on Mars.

The first crew won't need to do that: We can bring enough food for them. But if we want to build colonies on mars, certainly we're going to want to know how to grow food on Mars.

We're going to want to, of course, also do a lot of exploration, especially drilling, to look for subsurface water, which is both where the life might be, but also it could be source of both water and even geothermal power. We're going to want to...

FLATOW: Is the sunlight bright enough on Mars to grow crops and solar power?

ZUBRIN: Certainly at the equator on Mars, the sunlight is comparable to that in Alaska or Norway, which is a little bit less than plants would like, but there are certainly abundant biospheres and forests in Norway and Alaska, and you can grow crops there.

FLATOW: What about the trip? It's going to take a long time, and you might be weightless for that length of time. Doesn't that affect your bones and your ability to get off the spaceship once you get there?

ZUBRIN: Well, that would, if you went to Mars in weightlessness, and the weightlessness duration would be six months, which is the same as a space station shift. I actually don't recommend that. I don't think it's a good idea to go to Mars weightless. I think what we ought to do is rotate the spacecraft and give the crew artificial gravity, and that way we avoid all these physiological effects.

You know, I really frankly don't approve of this NASA obsession with zero-gravity research because what they're doing is they're subjecting human beings to an unhealthy condition just for the sake of researching it when there's a ready engineering answer to this.

It would be like doing research on oxygen deprivation of people to research for high-altitude pilots instead of just giving them an oxygen mask.

FLATOW: So what kind of craft would you build that had gravity, that could create gravity?

ZUBRIN: Oh, well, the way you would do that is this, is the habitat spacecraft is launched to Mars using the upper stage of the booster. So the upper stage is flying to Mars, too. Now, when its propellant is gone, it's just a hulk, but we can still use it as a counterweight on the end of a tether.

So we put the habitat craft on one end of the tether and the spent upper stage of the booster on the other end of the tether. The tether is about a mile long. We spin this thing up at one rpm. We would generate Mars normal gravity in the habitat. If we spinned it up a little less than two rpms, we would generate Earth gravity in the habitat. And this is how you prevent zero-gravity health effects, which have been severe and should be avoided.

FLATOW: Could you take the booster with you and land it on Mars and use it as something?

ZUBRIN: That would be difficult. The upper stage of the booster, I mean, think of something like the Saturn 5. It has a couple of lower stages, and then it's got the upper stage, which makes the final burn, which shoots the...

FLATOW: That's pretty small, yeah.

ZUBRIN: But also - nevertheless, it's not a shielded thing. It's built lightweight. It would burn up on entry at Mars.

FLATOW: All right, stay with us. We're talking with Robert Zubrin, who's author of "The Case for Mars: The Plan to Settle the Planet, Why We Must," 1-800-989-8255. Tweet us @scifri. We'll take your phone calls when we get back. Maybe you'd like to go. Tell us why. Stay with us. We'll be right back after this break.


FLATOW: I'm Ira Flatow. This is SCIENCE FRIDAY from NPR.


FLATOW: You're listening to SCIENCE FRIDAY. I'm Ira Flatow, talking with Robert Zubrin, author of "The Case for Mars: The Plan to Settle the Red Planet, Why We Must." He is also president of the Mars Society based in Golden, Colorado, 1-800-989-8255. Let's go to Rachel(ph) in Houston. Hi, Rachel.

RACHEL: Howdy.

FLATOW: Hi there.

RACHEL: How are you doing?

FLATOW: Hi, how are you?

RACHEL: I'm good. I think this is a great topic.

FLATOW: Would you want to go to Mars?

RACHEL: I definitely would want to go. It's almost like a sexy idea, like a reality show. This is the story of five strangers picked to live on a planet. I think from a sociological perspective, I think it would be really interesting.

FLATOW: But you know what? Maybe that's how you could fund some of it, by making it a reality show and having...

RACHEL: Why not?


FLATOW: I don't know how you'd vote somebody off the planet, but we could figure that out later.


FLATOW: All right, Rachel, thanks for calling. Have a good holiday.

RACHEL: Thank you.

FLATOW: What about the funding, Robert? What about how much money it's going to cost, and who would pay for this?

ZUBRIN: I think we could do a humans to Mars program within NASA's existing budget. NASA's currently getting 19 billion a year. That is the same amount, in inflation-adjusted dollars, as NASA's average budget was from '61 to '73, when we flew astronauts to the moon starting from zero space capability at the beginning of the program.

I think we simply have to spend NASA's budget better. I think the Obama administration, in, you know, canceling Bush's moon push without replacing it with anything and just doing a disorganized set of random programs, have done NASA an extreme disservice.

They're going to be spending three billion a year refurbishing the shuttle launch pads after the shuttle stops flying. That's pointless. They're going to be spending billions on researching orbital propellant depots to refuel interplanetary spacecraft that don't exist.

They're going to be spending billions researching a new electric thruster that's no better than the ones we already have while not developing the power source needed to drive either.

The way NASA can accomplish things, if it's given focus, it has enough money.

FLATOW: All right, let's go to Evan(ph) in St. Louis. Hi, Evan.

EVAN: Hi, Ira, I'm a huge fan of the show. Thanks for taking my call.

FLATOW: Thank you, you're welcome.

EVAN: The question I have is specifically with regard to rocket technology to be used to deliver a payload to Mars. I heard a reference to Saturn 5 rocket, of course, but I would be curious to know your guest's response to, say, Elon Musk's SpaceX, a company that's - I think the most recent heavy payload rocket is called Falcon Heavy. And whether it's a rocket that goes to the moon, and then there's a second-stage delivery between the moon and Mars, if that might be a consideration.

And also, I guess the second part to my question would be: Do you think it's most likely to be NASA or do you think it's likely to be a group, for instance, say through like the Lunar X Foundation? That's a private organization that might pursue a project like this to Mars. And I'm going to give a quick shout-out to my Moonbots(ph) robotics team, also through the Lunar X Foundation. I hope all those Lunar X Moonbots teams are listening to your show right now.

FLATOW: All right, thanks, Evan, have a good weekend.

EVAN: Thank you, you, too.

ZUBRIN: There's a lot of questions there. I'll try to answer at least some of them. The Falcon Heavy, there's a company called SpaceX, which is developing a new launcher called the Falcon Heavy. Now it's not quite a heavy-lift launch vehicle. It can - if it's successful, lift around 50 tons to orbit. A Saturn 5 could do 140. So it's not in the same class as a Saturn 5.

But it's much better than the 20 tons that the space shuttle could do or the Titan 4 or the Ariane 5 or the Atlas 5. So it is more than twice as good as any current medium-lift vehicle, and it's less than half as good as a Saturn 5.

I took a good look at the Falcon Heavy and I think we - with three launches of a Falcon Heavy, we could do a minimal, bare-bones human Mars mission. Now that is interesting because the SpaceX is saying they're going to sell Falcon Heavy launches for $80 million each. So that means for $240 million in launch costs, one-quarter the launch cost of a single shuttle flight, we could have sufficient launch capacity to do a human Mars mission.

So I hope SpaceX is very successful with this vehicle because if they do, in fact, introduce it, it's going to greatly reduce the cost of getting the human Mars program going.

FLATOW: Very interesting, the Mars Science Lab - this is the new Mars rover going to be launched in November - can it answer the same questions humans could without, you know, having the extra burdens of life support that - you know, you know the argument. Should we go with humans or should we do robots?

ZUBRIN: We should do both. I mean, look, we have orbiters orbiting the Earth to help us explore the Earth, even though we already have seven billion people here exploring the place on the ground. So even after Mars is settled, we will still send robots to Mars.

But that said, the idea that you could explore the Earth with a few rovers, I mean, we've landed three. Here's another one, and we're going to launch one more in 2018. You know, I live in Colorado, the Rocky Mountains. This is where the great dinosaur discoveries have been made. You could land 100 of these robots in the Rocky Mountains and you would never discover a single dinosaur fossil.

And the - you know, on the surface of Mars, we're going to want to do fossil hunting. The place was once a warm and wet planet that could have evolved life. It's not warm and wet anymore, but fossils could be there. We're going to need rockhounds on the surface and to set up drilling rigs to drill down a kilometer into the Martian surface and bring up samples of groundwater and bring them into a lab and subject to examination and biochemical testing.

These things are way beyond the ability of robotic rovers. So if we're going to find out the truth about the potential prevalence and diversity of life in the universe, we need to send human explorers to Mars.

FLATOW: If you have the plan and you say it's cheaper, why not approach other countries that are now space countries? You know, I'll name a few: China, India, Japan. Why not go to them and say: Hey, you know, you could be the first on Mars?

ZUBRIN: Yeah, if the United States wants to abandon its role as the vanguard of human technological progress, we could just sit back and hope that somebody else does it.

FLATOW: Well, you know, back in the '60s, when we went to the moon, we made a lot of stuff that's now made by other people. Don't we have to face the fact that we may not be the country to deal with anymore?

ZUBRIN: Well, look. You know, this goes to really the core question or one of the core questions anyway, which is why, especially given all the other problems that we have with our economy and the rest, should we undertake this? And I think there's a very strong reason.

I think the wealth and strength of a nation is based on its intellectual capital. Now, Apollo was extremely productive for this nation because it doubled the number of science graduates that we produced in this country at every level: high school, college, Ph.D. And we're still benefitting from that today.

The 40-year-old technologists who created Silicon Valley in the 1990s were the 10-year-old and 12-year-old little-boy scientists making the rocket fuel in the basement in the 1960s. And they produced zillions for our GNP and all the rest.

Now, a humans to Mars program today would be an invitation to adventure to every young person in this country. It would say to them: Learn your science and you could become a pioneer of new worlds. And out of that, we would get millions not just of little-boy scientists but little-girl scientists, too, because the scientific professions are open to women today in a way that simply was not the case in the 1960s, and engineers and inventors and technological entrepreneurs and doctors and medical researchers.

And these are the people that advance our economy. These are the people that strengthen our national defense. These are the people that find the cures to our diseases, okay, and advance human welfare.

The wealth of a nation is its intellectual capital. You know, we bombed Germany flat in World War II, and 15 years later, they're a dynamic economic power. That's because they had intellectual capital. There are countries on this planet, you could go there today, give everybody a million dollars, and 10 years from now, they'd all be as broke as they are right now.

So this is a tremendous engine for economic progress, technological progress and human welfare, and there's very little that can match it.

FLATOW: And who in Washington do you have to, you know, preach this to? Who do you have to convince?

ZUBRIN: We have to convince the president to give us a space program we can believe in.

FLATOW: That's sort of a takeoff on his theme, a space program we can believe in.

ZUBRIN: Yeah, that's right, a space program we can believe in. How about some hope and change and audacity? The - you know, how about a president that gets up there and instead of saying - I mean, look, this is not just Obama, okay. I don't want to be partisan here because Bush did the same thing. Okay, Bush got up there. He wanted to put a little sizzle on the space program. So in 2004, he said, you know, I've got a vision, we will return to the moon by 2020, which is basically an exciting goal - to a certain extent - but in any case, put off so far into the future that he didn't have to do anything to achieve it.

So, Obama comes in, nothing's been done, really. He cancels it, and so he comes up with another imaginary goal, an asteroid mission by 2025, which doesn't require him to do anything.

So instead, though, we're still spending 19 billion a year, as much as we spent on average during Apollo, except we're doing it to spread money around because there's 27 electoral votes in Florida and other electoral votes in Ohio and so forth. We could, you know, make just many people happy with NASA contracts, OK, but accomplish great things for the nation at the same time if we really had a goal. It requires vision, it requires embracing risk. But nothing great has ever been accomplished without risk.

FLATOW: All right. And there's the case. Robert Zubrin is giving his case, and you can read it, well-written in his book "The Case for Mars: The Plan to Settle the Red Planet and Why We Must." He's also president of the Mars Society based in Golden, Colorado. Always good to talk to you, Robert. Thanks for coming on again to SCIENCE FRIDAY. Have a good weekend.

ZUBRIN: Thanks for having me. OK. Same to you.

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