Traveling To Mars On A One-Way Ticket What if the only way to send astronauts to Mars is to leave them there for good? Lawrence Krauss, a physicist at Arizona State University and director of the Origins Initiative, argues that a one-way trip is worth considering, and that it wouldn't be hard to find passengers.

Traveling To Mars On A One-Way Ticket

Traveling To Mars On A One-Way Ticket

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What if the only way to send astronauts to Mars is to leave them there for good? Lawrence Krauss, a physicist at Arizona State University and director of the Origins Initiative, argues that a one-way trip is worth considering, and that it wouldn't be hard to find passengers.


You're listening to SCIENCE FRIDAY from NPR News. I'm Ira Flatow. This week, at NASA, an advisory panel released summary recommendations for the future of human space flight. And the panel found that one of the options, traveling to Mars, is a really good goal, but it costs a lot of money, a lot of money, and we're not quite ready to go there yet. It's 35 million miles away. The red planet is a long trip. There's a lot of stuff you've got to take along with you.

Well, my next guest has a solution. He says, well, we could solve a lot of that. We could save a lot of money if we send people, but we don't bring them back. That's an interesting option. Is that the best way to send people to Mars, is to leave them there for good? Would people go?

My next guest says it is worth considering, and people may be standing in line. Dr. Lawrence Krauss is the foundation professor of School of Earth and Space Exploration in the Department of Physics at Arizona State University in Tempe. He's also the director of New Origins Initiative over there, and he wrote an op-ed suggesting this one-way trip idea for the New York Times. Welcome back to the program, Lawrence.

Dr. Lawrence Krauss (Physicist, Arizona State University; Director, New Origins Initiative): It's great to be here, Ira.

FLATOW: So why would we save so much going only one way?

Dr. KRAUSS: Well, okay, first, from a monetary point of view, we'd save a lot because really, whenever you want to bring people back, you have to send the fuel for the voyage along on the way out. So that means you have to have fuel that powers the rocket ship that's also full of enough fuel to get back. And it's not just a factor of two. It's a huge factor in terms of just the cost of the fuel and the mass of the rocket ship.

Then you've got to, you know, design a device that can also take off from the planet and maybe rendezvous and provide the life support for another voyage. And, of course, the other thing you've got to do is figure out a way to get the astronauts back without having them die from radiation exposure, which is right now one of the biggest constraints. They get so much radiation on the 12-month trip that they might get a lethal dose on a round trip.

So, in fact, it's interesting that it - actually, after I wrote the piece, I was talking to Buzz Aldrin, who was quite interested in this, and maybe we'll get to it. But he was saying to me that some NASA people had estimated that it would really cost about 10 times more to have a round-trip mission than a one-way mission where you provided sustenance and a base where people could live.

FLATOW: But would you get people, really, who would like to go on a one-way ticket?

Dr. KRAUSS: Well, in fact, that's the other thing that surprised me. I mean, I wrote - I have to say I wrote this primarily - well, partly to propose something maybe more practical, but also to point out - as in some sense, the Augustine Commission did, too - that look, sending people to Mars is just so darn expensive that if we're going to do it, we've got ask ourselves the question: Why are we doing it?

What do we want to get out of this? I mean, do we want to just have a little joy ride and a few-day trip, or what do we want to do? And I'm not sure we really know, frankly, but this kind of modest proposal, if you wish, draws things into stark comparison.

But what surprised me is that I've been speaking to scientists, and in fact, it's - a lot of people in the scientific community have talked about this for a little while, that they'd be willing to go.

I don't want to mention names, but you'd be surprised at the number of people that have said they'd go, including former astronauts. And, in fact, Buzz Aldrin has been talking about this as the most practical long-term solution of getting a permanent base on Mars. And then what really prompted me was that a colleague of mine here in Arizona went out with a whole group from JPL for a geological field trip, and they talked about this and took a vote, and every single person said they'd go.

FLATOW: All these young kids.

Dr. KRAUSS: Yeah. I was surprised.

FLATOW: And this is almost like, you know, the age of exploration and the big ships coming from the Old World to the New World.

Dr. KRAUSS: Well, that's what I said. I mean, I said, you know, it sounds pretty mean to send them one way, but there's a long tradition of that in human history. The explorers didn't necessarily expect to come back. Certainly, colonists and pilgrims never expected to go home. And if we really want - if one of the purposes of human space exploration is to make the human race expand beyond Earth in case something happens to this planet, then we want to keep people on - we want to eventually have a permanent base, and it's not so clear we need to have this round trip. And, in fact, right now, the other thing is that the round trip would probably be fatal because of the radiation exposure.

So it's - what is certain is that we don't need to send humans to Mars, in my opinion, to do science. I think we can do it a lot more cheaply with robots, in fact - same with the other planets and Europa and a lot of interesting places that we need to explore. Most of the science that NASA does - in fact, essentially all the science that NASA does doesn't involve humans.

We send humans into space because we need to boldly go where no one has gone before, for exploration, for adventure. And I don't want to discount that, but if we're going to do it, we've got to say, you know, why are we doing it? And now how much are we willing to spend? And it's just such an expensive mission, and I think we have to start thinking outside the box.

This is certainly outside the box, and it's got a lot of people talking. I doubt - from a practical perspective, I think the hardest part of doing this is not the technical aspect, but convincing NASA and Congress that they would, you know - I'm not sure the public relations issue would allow NASA and Congress to do it.

(Soundbite of laughter)

FLATOW: Now, that doesn't mean that you might - that you cannot construct livable conditions on the planet.

Dr. KRAUSS: Yeah, I'm not saying send them to Mars and watch them die in a week, although, you know, that may be an option, too.

(Soundbite of laughter)

Dr. KRAUSS: But, no. I mean, you could actually create - potentially send enough - with unmanned ships, send enough material there to provide, yeah, a subsistence environment, to actually have them be colonists and not suicide missions.

FLATOW: And we know there's water, plenty of water on Mars.

Dr. KRAUSS: There's water. There's the basis of a - and there's carbon dioxide, and I mean, there's a lot - people have talked about terra-forming Mars for a long time. And you could probably - with plants and greenhouses and - create a subsistence region and have a colony. And that's certainly a practical possibility, I think.

It's just - what is clear now is that it's completely impractical to imagine anyone spending a trillion dollars or whatever it's going to cost to send humans on a round trip. And so part of the reason I wrote this was, you know, to be serious about an alternative, but also to provoke people and say - ask the question: Why do you want to go into space? What are you doing? It's not just a little, round-trip joy ride. If we're serious about putting humans elsewhere, then we've got to think about the consequences, and we've got to take - plan for that appropriately.

FLATOW: 1-800-989-8255, talking with Dr. Lawrence Krauss of Arizona State University. I did find, after reading your op-ed and doing some more research on this, it was surprising how many young people would be willing to get on a space ship, knowing that they're going to spending the rest of their life on another planet with no chance of coming back.

It sounds to me almost like some of these "Twilight Zone" episodes you see, you know, where they go onto another planet and they can't get back.

Dr. KRAUSS: Yeah, no. I mean, it does sound strange when you first think about it. Who would want to do that? But then, you know, people - I was going to pick a place that people move to and never come back, but I better not. I don't want to get a lot of letters.

(Soundbite of laughter)

Dr. KRAUSS: But it's so exciting. The idea, for a lot of people, the idea of being able to - the point is Mars is interesting, and that's the other thing we should point out. The moon is not particularly interesting, and it's not a very livable place. And sure, I'd go there if you offered me a chance for a round trip, but Mars is a place where you can - you know, it would be a fascinating place to explore, and there's lots of interesting stuff to do.

FLATOW: Yeah, because I was going to say, you know, you could - it would seem more practical - I mean, in terms of money - to go to the moon first and then go to Mars.

Dr. KRAUSS: But then the moon to me, personally, it just seems like a make-work project. And it's certainly more interesting than sending people up to the International Space Station, which in my opinion is just boring in the extreme and not particularly useful. There's not been any science. All you learn is how people can live 200 miles above the Earth's surface, and I'm not sure that's personally been worth 100-and-some-odd billion dollars.

FLATOW: Let's see if we can get a phone call or two from our listeners. Let's go to Miles in Cleveland. Hi, Miles.

MILES (Caller): Hi. I was wondering if, like, we don't have to think about bringing them back right now, but maybe in 20 or 30 years, when we have the technology. And we've done this a couple times, sent stuff there and back, supplies and such. Like, do you think people could come back on a more long-term basis, or would that be worth considering?

Dr. KRAUSS: Well, the answer is possibly, absolutely. You might imagine - one you decouple the departure and the arrival back, you might imagine ultimately having a ship to come back, or basically a one-way mission from Mars to Earth, and that's possible. In fact, you know, part of this was motivated, a fellow named Bob Zubrin, head of the - I think head of the Mars Society, had proposed this thing called Mars Direct, where you send a craft there before the astronauts, a separate craft that manufactures rocket fuel on the Martian surface using carbon dioxide, combining with hydrogen to make methane, and then there's already enough fuel for - so when the astronauts go there, there's a ship that can come back. And that's certainly a possibility. It's not necessary, but it's the kind of thing that could be done. So yeah, absolutely.

MILES: Thanks. I appreciate it.

FLATOW: Thanks for calling. And, of course, as you say, it is - it's such a political football to suggest that we're going to send people on a one-way trip, that no prospect of NASA funding something like this.

Dr. KRAUSS: Well, I think it's unlikely. I mean, someone was pointing out to me, you remember when John Kennedy said, you know, our mission is to send men to the moon and bring them back safely again, and the mission isn't over until they're back on Earth. And I think - and that mentality, I think, persists.

I think this is the kind of thing you'd have to - if you were serious about it, you'd have to take it over time and view as part of a longer-term plan of exactly how to explore the solar system.

So it didn't seem like you are - well, it didn't seem like admitting failure, but instead arguing that we're going to have the first - in fact, they way - actually, when I was talking to Buzz Aldrin the other day, he said to me, here's a way to make it sound politically good, that I will be the first president to say - I was the president who was offering this - to establish the first permanent human colony on another planet. Now, that sounds a lot less defeatist than saying we're going to send people on a one way…

FLATOW: It's good public relations to say it that way.

Dr. KRAUSS: Yeah. And I think, you know - and a lot of - look, a lot of - in my opinion, a lot of the aspects of human space travel is public relations. I think the reason we sent people to the moon in the 1960s wasn't - again, it wasn't for scientific breakthroughs. I mean, they did science on there, on the moon. But I think it was political and inspirational. And, in fact, I think human space travel really is inspirational.

When I was a kid, I stayed home and watched the astronauts land, and I wanted to be an astronaut. And I've been with astronauts on many occasions, and they're inspiring for kids. And that's great, too. I mean, I think that aspect has to be recognized.

FLATOW: Armand(ph) in Ypsilanti, Michigan, hi.

ARMAND (Caller): Hi. I have a question that's coming from a social science perspective, and I've got two parts to it. The first part is, so we're sending people to Mars on a one-way trip. I'm wondering kind of - there's this idea of entitlement that humans on Earth have a right to, not just to explore, but kind of colonize and make the rest of the solar system our own, as we've done on Earth.

And I think, you know, there's a lot of, you know, there's a lot of things we could talk about there with particulars of whether we've done a good job or not here so far. And I'm wondering what's the professor's perspective is on that, you know, why is it that we are allowed to go and kind of set up a colony there?

And then the second part is, I think there's - it would be really important to have a lot of social science input into the, you know - even the idea that this would be feasible option in terms of people getting there, not just having a "Lord of the Flies" kind of situation. And I'm saying this as a librarian and an anarchist(ph).


Dr. KRAUSS: Well, those are both good points. I think - well, I think we have a - I mean, from a right - perspective of rights, I think we can do what we can do, technologically. I mean, if we can do it and then there's nothing that stops us. In fact, the fact that we're doing such a bad job here on Earth may be another reason to send people elsewhere. One of the things I said in my piece is that one of the reasons pilgrims were willing leave where they were and never come back is that home was so bad.

And as I said, maybe in 100 years, the Earth will be so bad that people will want to go, anyway. But I think that - Steven Hawking has really said this very eloquently recently, that one of the rights is our survival. At some point, if you want to beat the odds, it's, you know, someday there's going to be a meteor that's going to hit the Earth that might wipe out all life on Earth, certainly above the oceans.

And so, what you want to do is you want to - if you really want humans to survive - and that's a decision, and it's true as a social decision - then you might want to distribute them among the solar system. But your second point is really well taken. It's really the stuff of science fiction. In fact, I've been talking to someone about this very issue.

You've got - how many people is the minimum number for a colony, and, you know, how do you ensure that people don't go crazy? And what if someone in Mars goes crazy? And there's also - you can imagine a whole bunch of scenarios. And - but there are questions you have to deal with…


Dr. KRAUSS: …and I think that was pretty well part of the purpose of writing this is get people to say, look, you know, what are we going to do and how are we going to take this seriously?

FLATOW: I'm talking with Lawrence Krauss of Arizona State University on SCIENCE FRIDAY from NPR News, author of "The Science of Star Trek." And I - you slipped in that little reference to going where no one else has.

(Soundbite of laughter)

FLATOW: I caught it, Lawrence.

Dr. KRAUSS: Thank you. I had to. I'm contractually obliged.

(Soundbite of laughter)

FLATOW: 1-800-989-8255.

You said that it's almost - you're almost saying that, you know, not just thinking about these things, but you should be setting up the mechanism for creating the technology we would need to live on another planet, maybe.

Dr. KRAUSS: Yeah. Well, I think - I mean, exactly. You should be doing the things that are rational. And so, if you - once again, I hate coming back to it, but you - I don't think people have really framed the question of, what is it - why are we sending humans into space? And I think an honest discussion of that is required before we're willing to spend the kind of money to do it.

FLATOW: Mm-hmm.

Dr. KRAUSS: And too often, it's confused with science. And as a scientist, I'm very sensitive of that because, you know, when the International Space Station has a billion dollar cost overrun, that may be more than all of what NASA is spending on science. And if we pretend that humans in space is a scientific frontier, then we'll take money away from the real science.

And, you know, the - look at the rovers on Mars. They - you know, we talk about going to Mars, but we're already there. You know, you can look at wonderful pictures and those - I like to think of those little rovers, there alone five years later, just sort of moving on their own. We don't mind that they're there alone, but they're plugging away, doing amazing things. And it's true that a human in a very short time could do what the rovers may have taken a month to do in terms of looking at rocks and stuff.

FLATOW: Mm-hmm.

Dr. KRAUSS: But first of all, for the price of sending a human to Mars, we can probably send 500 rovers. And secondly, with the time it's going to take, which is maybe a generation, at least, you can imagine that robots are going to be, you know, much better, if not better than humans in a generation. So you really have to think, why are we sending humans? And if it's really to colonize space, if it's really for us to live elsewhere, then we should take seriously what's required to do that.

And as you said, part of that is imagining what it takes to build a sustainable colony, and imagine how to save money since…


Dr. KRAUSS: …it's going to be expensive.

FLATOW: And this is a topic that comes up every now and then. And, you know, one of your colleagues, Paul Davies, over there at ASU has also written about this. Other - as you say, other scientists have written about this. But now, it seems to be maybe a good time…

Dr. KRAUSS: I guess so.

FLATOW: …to talk more about it.

Dr. KRAUSS: I was surprised. Yeah. And, in fact, I didn't know Paul has written about this. He wrote about five years ago and - I wrote about this. And I was kind of surprised at the reaction. I think it must be the right time, because the reaction has been remarkable. In fact, JPL's - you know - invited me over to lecture on this. And it's been surprising to me. So there's something in the air. And I think probably it's because the Augustine Commission was beginning to think what, you know, what…


Dr. KRAUSS: …what's realistic for human space exploration? And there's a time when the nation is really beginning to perhaps seriously think about what we're going to do next and what the cost is going to be.

FLATOW: All right, Dr. Krauss. Thanks for joining us.

Dr. KRAUSS: It's great. It's always good to talk to you, Ira.

FLATOW: Thank you, Lawrence. Dr. Lawrence Krauss is director of the Origins Institute and physicist at Arizona State University.

We're going to take a break and switch gears and come back and talk about primate music, apes and monkeys talking - I don't know, talking about music, making music, listening to music. It's quite surprising the kind of rhythm and music that they can create. And we have some examples of that. So stay with us. We'll be right back after this break.

(Soundbite of music)

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

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