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« Back to Should We Send Men to Mars? main page    Transcript for: Should We Send Men to Mars?Think Tank Transcript ANNOUNCER: Think Tank is made possible by AMGEN, recipient of the PresidentialNational Medal of Technology. AMGEN, helping cancer patients through cellularand molecular biology. Improving lives today and bringing hope for tomorrow. Additional funding is provided by the John M. Olin Foundation, the LillyEndowment, and the Lynde and Harry Bradley Foundation. (Musical break.) MR. WATTENBERG: Hello, I'm Ben Wattenberg. On July 4th, 1997, the NASA probePathfinder is scheduled to land on Mars. It will release a land rover namedSojourner to study the surface of the planet. Pathfinder, Sojourner, those aremachines. Are they the legitimate heirs of Marco Polo, Christopher Columbus,Neil Armstrong? Joining us to explore that idea today are Robert Park, professor of physics atthe University of Maryland, and director of the Washington Office of the AmericanPhysical Society; William Sheehan, a psychiatrist and historian of science,author of several books, including The Planet Mars, A History of Discovery andObservation; and Rita Colwell, president of the Biotechnology Institute at theUniversity of Maryland, and a former president of the American Association forthe Advancement of Science. The question before this house, should we send mento Mars, this week on Think Tank. (Musical break.) MR. WATTENBERG: The story of human fascination with Mars goes way back. TheEgyptians called Mars, the Red One. The Babylonians called it the Star of Death. Today, Mars continues to fascinate us. (Video break.) MR. WATTENBERG: It also raises a monumental policy question. In 1969, Americasent men to the moon, not machines. It may well have been the definingachievement of the American century. That was then, now is now. Should we launcha similar manned effort today? The argument is made that human beings areexploratory creatures, and that mankind needs big ideas and big projects toennoble and inspirit society. The Egyptians built pyramids. In the Middle AgesEuropeans built cathedrals. Today we build rocketships. Further, the recent claims that life once existed on Mars have only whetted theappetite of the Mars boosters. But there is a counter-argument. Don't we havebetter things to spend our money on? Sending people to space costs a lot morethan sending machines. Why not send machines and spend the difference for newmedicines, or to teach literacy, or to explore the depths of the oceans righthere on our home planet. Lady and gentlemen, thank you for joining us. Let's go around the room quickly,starting with you, Bob Park, why is there this current fascination with allthings Martian? MR. PARK: Well, aside from 80 years of science fiction, which certainly has alot to do with it, it is that that is the one place in our solar system, with thepossible exception of the moon Europa around Jupiter, that we think wemight find either life or fossil life. It's been pretty well ruled out, I think,from what we know of the other planets, and so this is -- that is an incrediblyimportant discovery, if it's there. MR. WATTENBERG: Bill Sheehan, you're a psychiatrist was well as a Martianstudent. Why the fascination, the urge? MR. SHEEHAN: Well, I think you alluded to it in the introduction that you gave. Mars has fascinated people for thousands of years, and the intensification ofthat in the last three centuries is, Mars has been found to be the planet that isthe most earth-like. By the 18th Century it was found to have what were thenthought to be continents and oceans, polar caps, a rotation period similar tothat of the Earth, and seasons. And about 100 years ago, there were also linearformations that were observed on Mars that proved to be illusory, but werethought to be the famous canals of Mars, and that triggered an enormous debatewhich, in some ways, parallels that which we're going through right now with the-- MR. WATTENBERG: That was just about when we were building lots of canals here onEarth. MR. SHEEHAN: Well, the Suez Canal was built in 1869, so there was a topicalinterest in canals. But I think that Mars is a place unique in the imaginationas well as a place unique in the solar system, as Bob indicated. MR. WATTENBERG: And, Rita Colwell, why are we all sort of hung up suddenly onMars? MS. COLWELL: Oh, I think that it's an opportunity to understand the evolution oflife on Earth. As a biologist, it gives us clues as to how life formed. It givesus clues about life beyond this planetary system. I think it's an opportunity tosort of trace our history in biochemical and molecular genetic terms. But I thinkthe main thing that it would do for us, here as humans, it would give us a senseof the actual beginnings of life in terms of the chemistry, the structure, andthe evolution to the higher forms that are there. Now, that's presupposing youfind only primitive forms. We may have some surprises. MR. SHEEHAN: We should say that this is presupposing there is bacterial life onMars, which is not a settled question. And I do think that that's the keyquestion that we're going to attempt to find out. And perhaps the spacecraftwill. MR. WATTENBERG: How far away is Mars? MR. SHEEHAN: It's closest to the Earth 35 million miles. It never gets closerthan that. MR. WATTENBERG: Pathfinder is scheduled to land on the surface of Mars on July4th, 1997. What can we expect from this mission, from Pathfinder and Sojourner? MR. PARK: They, of course, are going to be looking for any evidence that theremight be water somewhere, even if it's subsurface, again, there be any evidenceon the surface. They will, of course, look for evidence of life. But this not-- these are not missions designed specifically to look for that. They are goingto be looking for landing sites. They're going to be studying the geography. They're going to be -- this is kind of a cut-rate mission. Even the lander hereis, you know, it's landing with an airbag to keep it from being demolished. It'snever been tried. And, if all goes well, we'll be able to look atMars through its eyes. And that's a wonderful thing. In a sense, we'llall be along on that mission. MR. WATTENBERG: What's the differential between -- I mean, just ballpark betweensending up something without a person and with a person? MR. PARK: A factor of 10 is the number that's often used, but it's, in myexperience, more than that. MR. WATTENBERG: I mean from what to what? MR. SHEEHAN: A billion dollars. MR. PARK: Yes. It depends on what you're trying to do, but a billion dollars isaround there. MR. WATTENBERG: So we could put a man on Mars or a woman or both for $10billion? MR. PARK: I don't believe it. MR. WATTENBERG: I mean, I've seen estimates as high as $50, haven't I? MR. PARK: Oh, there have been estimates of almost a trillion. That's why theygave the idea up some years ago. MR. WATTENBERG: So it's not a factor of ten in that case. MR. PARK: In going to Mars, it's going to be much higher than that. MR. SHEEHAN: In fact, at this point, we really don't even have it worked out howthat would be done. MR. PARK: We don't know if we could get people there alive. MR. SHEEHAN: Right. We've had people in Earth orbit for about a year, andthat's the endurance record. It would take, you know, as Bob mentioned, ninemonths one way, given our current technology to make it to Mars. So we don't atthis point even have an experience with human beings being in space for thatlong. MR. WATTENBERG: Some of you have been arguing that it's too expensive and toodifficult to send a man to Mars. We recently had occasion to interview anengineer from the National Space Society, Robert Zubrin, who has written a bookabout how to get to Mars on the cheap. Here's what he said. MR. ZUBRIN (From video): If we want to go to Mars, there's a way to do it for acost more on the order of $20 to $30 billion. And that is by doing Mars in thesame way that people have explored the Earth, which is by making use of localresources. Mars has got an atmosphere which is made of the ideal feedstock formaking rocket propellant. So if you take advantage of that, okay, in the samewhat the pioneers on Earth have always taken advantage of living off the land --Lewis and Clark would never have crossed America if they tried to bring alltheir food, water, and oxygen for themselves and their horses with them. If youtake advantage of this in space, we can do this much cheaper. So, if you want togo to Mars, you don't build giant Battlestar Galactica spaceships filled with thepropellant to come home, you go to Mars in relatively small spacecraft, and youmake your return fuel and oxygen there. Here's how you do it, okay, with your first launch, you shoot out to Mars amedium-sized payload consisting of an earth return vehicle, which flies to Marsunfueled. And you land this thing on Mars after an eight-month trip out to Marson a low energy trajectory. And then, when you get there, you run a pump and yousuck in the Martian air, which is 95 percent CO2, had you react that with somehydrogen that you brought with you from Earth in a series of chemical reactorsthat are very simple, okay. You can turn that combination into methane fuel andoxygen oxidizer. And now you've got a fully fueled Earth return vehicle waitingfor you on the surface of Mars. MR. PARK: It's kind of a preposterous idea. He says, look, we don't even haveto take all the fuel to get back, we'll just make fuel out of the atmosphere,which happens to be carbon dioxide, which, you know, when I learned chemistrythat was the product of combustion. But that's no problem, he says, we'll takealong -- MR. WATTENBERG: Some of the first successful explorers of the South Pole didlive off the land. And when the earlier ones took everything -- MR. PARK: But they ate their dogs. They took -- in a sense, they took the foodwith them and used it for transportation, then ate it. MR. SHEEHAN: Well, I think part of the problem is that some of the technologieshe's talking about are totally untried. MS. COLWELL: I really don't think it's a matter of finding the kindling wood tobuild a fire and heat yourself. I think it's far, far more complicated,especially for returning. The return journey requires that you have to have sortof the -- you have to have the same supplies and fuel and so forth to get there. That has to be planned, I think. MR. WATTENBERG: So we could categorize this whole thing as pie in the sky,right? MR. SHEEHAN: Pull yourself up by your own bootstraps. MR. WATTENBERG: Right, okay. Next question, so what is the argument for sendinghuman beings to Mars? Let's get -- cut to the chase. MS. COLWELL: I think the strongest argument is sort of the Missouri mule of theshow me sort of argument that it's there. And the kinds of observations you canmake as a human being are just far greater than you can make by instrumentation. The opportunity to do manipulations, to do experiments. It just is a much richerkind of exploration. MR. SHEEHAN: I would say that it's an intangible argument. I think it would bevery difficult to argue for putting humans there in any utilitarian sense, anymore than it would make sense to have people up there with the Hubbell SpaceTelescope. I mean, obviously, all of these things can be done in anautomated form. It's much cheaper to do it that way, and one can, as with thisspace mission, send a lot of hardware up there inexpensively for the cost ofdoing a human mission. I think that in some ways we have to, if we're going todo this Mars trip, and given the expense of it, sell it as an adventure of thehuman spirit. We'll have to somehow capture the imagination of people, andemphasize the fact that this is in some way an entertainment for an inquisitive,and ultimately adventure bound species. MR. WATTENBERG: I mean, this is sort of Spielberg cubed, you can -- that's thereason for it, because you could have a great picture show about it? MR. SHEEHAN: Well, I think that to some level we have to be able to do thatbecause -- you know, I think the people watched the television broadcast from themoon, and they saw the shadowy images of astronauts bouncing around up there, andlost interest very quickly. So I really -- I think we would have to sell this asthe 21st Century analog to the cathedrals. The cathedrals were not built becauseof some sort of utilitarian purpose. MR. WATTENBERG: But, serious, but you would like to see human beings on Marsduring your life time? MR. SHEEHAN: I've been fascinated with Mars my whole life. And personally, yes,I'd like to see it done. It would be an adventure that -- MR. WATTENBERG: You think it would be worth the cost? MS. COLWELL: Sure, I think there is a symbolism, just as Bill has expressed, ofthe human spirit and the exploration and the inquisitive nature of human beings. But, more than that -- MR. WATTENBERG: But, your field is biotechnology. MS. COLWELL: Yes. MR. WATTENBERG: I mean, here you have this incredible experiment and adventuregoing on in biotechnology, the human gene, all the possible cures. I mean, wehave -- let's stipulate for the sake of this argument that we have a finiteamount of funds to spend on exciting ideas. Why is it more exciting to go toMars than to try to cure cancer or whatever, you fill in the blank, do greatbiotech things? MS. COLWELL: I think that one of the outcomes of landing on the moon was that itabsolutely broadened the perspective, the imagination of the whole globe. Ithink it did something that was very important. It took us out of our owncocoon, so to speak, maybe to a larger cocoon, but it was a wider view of life inthe planetary system. And I think this will just take it another substantiveleap into space exploration. So I think it's part of human nature. With respect to your question about other kinds of experiments, that's going togo on anyway. And certainly, we're not talking about going to Mars in a week or ayear or several years. I think we're talking about iteratively developing thecapacity, technologically, to eventually be able to do this and I think we shouldhave that as an objective. MR. SHEEHAN: I think that -- you mentioned the cure for cancer, for example. That's clearly something that's going to be incrementally achieved. But,the question of whether or not there is or was life on Mars is a question towhich conceivably in our lifetimes we can get a yes or no answer. We'll be ableto find out whether or not life was on Mars. And that is an extremely importantquestion from a philosophical point of view. Are we alone in the Universe? MR. WATTENBERG: Bob, the poets and the philosophers have spoken. Now it's yourturn. MR. PARK: Well, I like to think of myself as a poet and philosopher, too. AndI'm inspired as well. But, I'm -- MR. WATTENBERG: But, you have a checkbook that you have to -- MR. PARK: I'm inspired by what we can find. Now, when a human being is on Mars,it's not a like a human being on Earth. He's locked in a space suit. He has nosense of touch. He has no sense of smell. There is nothing to hear. The onlysense he's got left is his eyes. And we can put better eyes than human eyes onMars. And we can see through those eyes from here on Earth. It is not thatwe're putting a robot up there that has to do our thinking for us. We can react. We see what the robot sees. We tell the robot what to do. It's tele-robotics. And that's why I say when we send a robot to Mars now, with tele-robotics, we'reall along on the mission. And I find that is as exciting and as inspiring asanything else we could imagine. On Earth we do not send human beings down to investigate the interior ofvolcanos. MS. COLWELL: We do. MR. PARK: Or the deep -- well, we do, but only to a very limited extent. Wesend robots down there. We drop robots down into deep holes in the ocean. Andfor the simple reason, scientists are accustomed to making measurements withtheir instruments. You don't stick your finger in a hot liquid to see how hot itis, you put a thermometer in. And we're used to sending our instruments. We can-- every year our robots, our machines get better. Human beings haven't changedin 30,000 years. We are a pretty fragile device to try to send to Mars. MR. WATTENBERG: Don't our little boys and girls need heros and heroines to say,look at him, look at her, she's there? Is that -- MS. COLWELL: I'd even ask the question differently, would you have been asexcited about a robot landing on the moon than Neil Armstrong? MR. PARK: Well, I'll tell you, I had the experience, I took my students out toNASA to watch on the big screen, live, as we did the first fly by of Neptune. And my students watched that image of this eerie blue planet forming on thescreen. They were every bit as excited as I had been seeing Neil Armstrong steponto the moon. MR. WATTENBERG: But, I mean, if Columbus had been a one way voyage and all itsend back was some television of San Salvador, would that have revolutionized theworld? MR. PARK: Sure, if Queen Isabella could have send a robot she would have,because it would have been a lot quicker and a lot cheaper. But, shedidn't know how. MR. WATTENBERG: Right. Do we need heros, heroines? MR. SHEEHAN: Well, I think we do need heros. I don't think that the impact ofeven the Voyager images, which fascinated me as well was the same as -- the eyesof Voyager are not my eyes. MR. WATTENBERG: Bill Sheehan, you have written a -- the title of your book is,The Planet Mars, A History of Discovery and Observation. And you are a historianof science. Is there echoes of -- that go back thousands of years of peoplesaying, well, we can't do it? Is that the wrap on -- MR. SHEEHAN: Well, we have barked up this tree before. People have beendeclaring the existence of life on Mars on an incorrect basis for a century andmore. So I think that there is, at least in my mind, a considerable degree ofdoubt that the findings about life on Mars are actually going to hold up. But, Ithink if we do find evidence of bacteria on Mars, whether currently extant, whichwould be more exciting, but if there are fossil bacteria on Mars, and we canconfirm that with robotic space craft, I think that then things will move to awhole different plane. I think then there would be a reason to justify perhapsthe mounting of human explorations to Mars, because that would be a staggeringdiscovery, the likes of which -- you know, it's very difficult to imagine whatwould have more of an impact. But, I think that we'll have -- MR. WATTENBERG: Why would that have such an impact, if you said there are somebacteria on Mars? I mean, why would that -- MR. SHEEHAN: Well, there are two questions and Rita can answer part of this. But, just my quick response to that, the first thing that will have to be settledis did life independently arise on Mars? Are these bacteria that originated thereor did they have a common origin? Since we have meteoritic material that haslanded on the Earth, it's possible that life has been seeded through the solarsystem and may have started in one place. But, if in fact life did originate on Mars independently, then that means thatthe preconditions for life are fairly common in the cosmos. And that doesn'tmean intelligent life. But, it means that metabolism, the cellular structure,all of these things, can be assembled within a relatively short time of thebeginning of the solar system. MR. WATTENBERG: But, the original space program had some very practicaladvantages to the human species and to Americans, specifically. It had amilitary application in terms of the Cold War. Despite all the talk about Tangand Team and Wing and Wang, what we did get was satellite technology out of it,which has been -- MR. PARK: Which is fantastic. MR. WATTENBERG: Which is fantastic. MR. PARK: The global positioning system being the latest of these. MR. WATTENBERG: Right. But, I hear the optimists here, or the adventurers here,saying that we're going to learn something theoretical about bacteria,maybe, what is the pay off? Why do you -- MR. PARK: Because, I'm as excited about that as they are. MR. WATTENBERG: Yes, but you're not prepared to take as much of my money to doit? I am representing the vast -- the great taxpayers of America. I mean, Ihappen to sort of agree with the optimists, by the way. MR. PARK: I'm a taxpayer too. MR. WATTENBERG: I understand that. MR. PARK: But, quite aside from that, I'd be perfectly willing to spend themoney, if it were the best way to do it. MR. WATTENBERG: So you wouldn't even send a manned mission to Mars if you hadthe money? You'd rather do it without? MR. PARK: It's just a better way. MR. WATTENBERG: A better way? MR. PARK: I mean, we're a bag of living organisms. You have one accident onMars and you can't do the experiment after that. There are more living organismsin my gut than there are human beings on Earth. MS. COLWELL: Yes, but I have to say, Bob, that you kind of have it both ways. On the one hand, you are discussing how insulated and capsulated the human beingwould be. And then at the same time you're saying that we would becontaminating. I think to answer -- MR. PARK: Depends on the accident. MS. COLWELL: Sure, of course. But, I think the issue really is, as Bill hadlaid it out, is that it's understanding the ability of a complicated structure,which is a living organism, to have arisen independently, or whether the socalled theory of pan spermia, which means the transmission of seed through cosmicspace, that would seed all of the bodies of that planetary system. That's an oldtheory that, you know, was proposed in years past. But, the notion, still,would be amenable to testing the hypothesis that there was de novo origin of lifeon Mars and if it's very, very different then it would give us some indication,perhaps of the extreme -- MR. PARK: The difficulty is that if there is life, even microbial life, it isvery likely underground, because the radiation levels, again, on Mars, which doesnot have a magnetosphere to protect is, are probably too high for anything tosurvive on the surface. MS. COLWELL: Well, again -- MR. PARK: It doesn't have to be very deep. MS. COLWELL: As amicrobiologist I would take issue. We do have a bacterium species radiodurans(sp), which has been isolated from nuclear reactors where in fact it canwithstand tremendous amounts of radiation. So do not underestimate the capacityof microbial life to live in true extremes. MR. SHEEHAN: And just to build on that, at one time oxygen was extremelypoisonous to living things. So I think whatever kind of Martian life we find, ifwe do find any, will have evolved to adapt to Martian conditions. If there isn'ta reason to send people to Mars, the next place isn't very apparent on thehorizon. There aren't a lot of other candidates. MR. PARK: Well, Europa, one of the moons of Jupiter, and it's an ocean moon. Now, the ocean is frozen, but there is a lot of evidence that, in fact,underneath that ice, at some depth, there is liquid water. And a lot ofbiologists believe, if that's so, and that there is enough heating in theinterior from the Jovian tides, that life would form there very well. MS. COLWELL: Having done experiments in the Antarctic, in the dry valleys, wherebacteria live in the rock and have only a very small amount of time per day inthe "summer" they still grow. So it would seem to me, if there is liquid my betwould be that there is living bacteria. MR. WATTENBERG: All right. We have to close it out with that. Let me announcethat you are all correct. Thank you very much, Bill Sheehan, Rita Colwell, BobPark. And thank you. I'm Ben Wattenberg for Think Tank. ANNOUNCER: We at Think Tank depend on your views to make our show better. Please send your questions and comments to: New River Media, 1150 SeventeenthStreet, Northwest, Washington, D.C. 20036; or e-mail us at thinktank@pbs.org. To learn more about Think Tank visit PBS On-line at www.pbs.org. And please letus know where you watch Think Tank. ANNOUNCER: This has been a production of BJW, Incorporated, in association withNew River Media, which are solely responsible for its content. Think Tank is made possible by AMGEN, recipient of the Presidential NationalMedal of Technology. AMGEN, helping cancer patients through cellular andmolecular biology. Improving lives today and bringing hope for tomorrow. Additional funding is provided by the John M. Olin Foundation, the LillyEndowment and the Lynde and Harry Bradley Foundation. END Back to top  Think Tank is made possible by generous support from the Smith Richardson Foundation, the Bernard and Irene Schwartz Foundation, the Lynde and Harry Bradley Foundation, the John M. 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