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“Houston We Have a Podcast” is the official podcast of the NASA Johnson Space Center from Houston, Texas, home for NASA’s astronauts and Mission Control Center. Listen to the brightest minds of America’s space agency – astronauts, engineers, scientists and program leaders – discuss exciting topics in engineering, science and technology, sharing their personal stories and expertise on every aspect of human spaceflight. Learn more about how the work being done will help send humans forward to the Moon and on to Mars in the Artemis program.
On Episode 121 Dr. Harrison Schmitt, the Apollo 17 lunar module pilot and the only geologist to walk on the Moon, discusses the 50th anniversary of the Apollo program, his Apollo 17 mission, what is scientifically interesting about the Moon, and what we have to look forward to during the Artemis program. This episode was recorded on April 15th, 2019.
Gary Jordan (Host): Houston, we have a podcast. Welcome to the official podcast of the NASA Johnson Space Center, Episode 121, Apollo 17. I’m Gary Jordan. I’ll be your host today. On this podcast, we bring in the experts, scientists, engineers, and astronauts all to let you know what’s going on in the world of human spaceflight. We are in the middle of celebrating 50 years of the Apollo program. This summer 2019, we focused on Apollo 11, as we passed 50 years since the first landing of humans on the Moon. Just recently, we passed 50 years since Apollo 12, where Pete Conrad and Alan Bean became the next two men on the Moon on November 19th, 1969, while Richard Gordon flew solo in the command module. Not a smooth ride to get there either, as the Saturn V was famously struck by lightning during ascent on November 14th. And [Electrical Environmental Consumables, and Mechanical Systems] EECOM, John Aaron in mission control suggested switching quote [Signal Conditioning Equipment] SCE to Aux. No one quite knew what that meant, but they did it, it worked, and the crew were able to navigate to the Moon with Conrad saying “whoopee” as his first word as he exited the lunar module first onto the lunar surface. Conrad and Bean conducted two spacewalks, set up some science experiments, took color video, collected rocks and pieces of the Surveyor 3 probe that landed on the surface more than two years prior. And then they returned safely to Earth on November 24th. So, in the spirit of the 50th anniversaries, I had a chance to sit down with Dr. Harrison Schmitt recently, the lunar module pilot of Apollo 17, and the only geologist to walk on the Moon. He came to our studio to speak about the 50th anniversary of the Apollo program. But I had the chance to ask him more about his Apollo 17 mission, what is scientifically interesting about the Moon, and what we have to look forward to during the Artemis program. So, here we go. Forty seven years after his launch to walk on the Moon, Dr. Harrison Schmitt. Enjoy.
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Host:Dr. Schmitt, I am very honored to be speaking with you today. Thank you for joining me. We’re now 50 years past this historic Apollo program. Thinking back on this momentous time in American history, I wanted to start just before you came to NASA, or even shortly after, what were some of the more interesting geological questions that you wanted to answer when looking at the Moon?
Harrison Schmitt: Well, the Moon had long been an area of scientific fascination for geologists, as well as astronomers. And I think the main thing that we were, needed to know is how old was the surface of the Moon, how old were the rocks that we could see from using telescopes? And also, well, because, mainly because that would tell us how much of Earth history it was going to record, because the Moon has been in the vicinity of the Earth as a planet for billions of years, but we just didn’t know how long that was. And so if there was one fundamental question that related directly back to the Earth, it was how old was the Moon?
Host: Now, tell me about when, when we were looking at the Apollo program, actually putting boots on the surface of the Moon, what you did to study the Moon, pick out the best locations in the more interesting geological parts of it.
Harrison Schmitt: Well, the initial selection of landing sites was based purely on operational considerations. What were the smoothest areas that we could identify using the photography that the Lunar Orbiter unmanned satellite of the Moon had provided. The Lunar Orbiter program, and the Lunar Surveyor program, the Soft Landing program, had been in the mix even before Kennedy made his announcement. And they were programs that then were transferred over into the Apollo program office and then retargeted in order to examine those areas that might, around the equator that might be most favorable for landing. And so the first two landings were basically related to those early landing sites. And then as we got more confidence, we started to expand the landing sites until finally with Apollo 17, the mission I flew on, we landed in a valley deeper than the Grand Canyon. And only about seven kilometers wide. So, it was really a spectacular evolution of the landing site selection.
Host: It was really–establishing the confidence of the operation itself. Given that, this was a fairly new operation. You know, we were just getting to the Moon.
Harrison Schmitt: Well, it was new, you know, in fact, people had to realize, Apollo 11 was a test flight. Nobody knew for sure that we were going to be able to land on Apollo 11. And, of course, we came close to not landing on Apollo 11. But, nevertheless, through the skill that Neil Armstrong showed, we were able to do that. And also, the knowledge that was present in Mission Control Center, we can’t forget how important a role they played in the Apollo program. And you also have to keep that in mind of when you decide you’re finally going to go to Mars, mission control won’t be nearly as involved. There will be a planning operation, but not a real time part of the actual landings on Mars.
Host: Very true. Now, you said Apollo 11 was selected mainly because of operational constraints, making sure that we can successfully land on the Moon. That was one of the big parts of why we selected that site.
Harrison Schmitt: Well, it was a little more complicated than that.
Harrison Schmitt: Because Apollo 8, Frank Borman, Bill Anders and Jim Lovell’s mission, was targeted to the farthest east landing site that we had determined would be acceptable for Apollo. And when they were able to view that landing site using a ten power monocular, they felt very confident, Bill Anders in particularly, that it looks pretty good. And so when Apollo 10 came along, I suggested to Tom Stafford that maybe we ought to ask management to shift their landing site, one Apollo landing site, westward. So, they would have a chance to look at a second site, as well as a third site, because they were going to be in orbit longer. And we spent quite a bit of time with management trying to convince them that that was a good plan, and eventually prevailed. And so the planned landing or launch day for Apollo 10 was shifted by one day in order to see two more sites. Well, as soon as you did that, that pretty well determined where Apollo 11 was going to land. They were going to land at the targeted site for Apollo 10.
Host: Now, this site, of course, being, you know, operationally the chosen landing site for Apollo 11, what geologically was interesting about it?
Harrison Schmitt: The main thing that was geologically interesting about Apollo 11 was gathering a broad suite of samples. And that’s, indeed, what Neil did. Neil did a fantastic job. In about 20 minutes, he gave us one of the best collections of lunar rocks that we’ve ever gotten in a short amount of time, including the soil of the Moon. He told me later that he looked at that rock box that he was putting the rocks in, and he said it looked awfully empty, so he just filled it up with soil. Even though, you know, it’s a famous number, ten zero zero eight four is the soil from the Apollo 11 site. And it’s extremely important soil. Not only did we get the age, we found out the Moon was very old from the rocks that Neil brought, collected. But that soil has given us great insights into the resource base that the Moon represents, not only for lunar settlements, but also potentially for use here on Earth, namely a fuel for fusion power, light isotope of helium that is present in those soils. And then again resources that can help us go to Mars.
Host: Now, as a geologist, I’m sure you had a drive to actually put yourself on the Moon and look at all these fascinating sites from your own eyes. Tell me about your drive to go through the training for other systems; command module training, lunar module training, to become an astronaut and actually fly to the Moon as a geologist.
Harrison Schmitt: Well, as you can gather from Deke Slayton’s book “Deke,” he did not think that they needed scientist astronauts. And so the challenge in front of all of us, scientist astronauts, the six that were selected, was to become as operational pilots as they possibly could. Not only jet pilots and helicopter pilots, but also to be as good as anyone at operating the spacecraft. And so that was the challenge in front of me, that if I was ever going to have a chance to be part of a crew that went to the Moon, I would have to be as good as anybody else.
Host: Now, reflecting on specifically Apollo 11, can you tell me about where you were, where you remember being during that mission, and what were you doing?
Harrison Schmitt: Well, most of the time, Apollo 11, I was in mission control. I had spent a great deal amount of time both with the training of the crew, with the monitoring of the configuration and packing of the descent stage, and also with the planning of the little bit of EVA activity that they were going to have, and so I spent a great deal of time, as I did for all the missions except my own, in mission control. That’s where the action was. And that’s, and those were the people you were going to be dependent upon once you were in space. So, I have great respect and a lot of great friends in mission control.
Host: Looking back 50 years, can you tell me your thoughts when you saw Neil Armstrong take those first steps on the Moon?
Harrison Schmitt: Well, it was exciting for everybody. And primarily because of the patriotism. People have to remember that Apollo 11, the whole Apollo program started out initially as a part of the Cold War, the competition between Communism and the Soviet Union and democracy in the United States. And the people who signed up for Apollo, 450,000 Americans were in this primarily because of their patriotism and their belief that it was critical to the competition that then existed in the Cold War. And so it was mainly a patriotic feeling I think that we all had, particularly those of us in mission control, that the success really was what Kennedy had asked us to do, what Eisenhower had helped plan and develop technologies to do, so that we really did make a difference in the Cold War. I think we all felt that it may have made a big difference. And subsequently émigrés from the then Soviet Union made it very clear that once we had landed on the Moon, indeed, once we had launched the Saturn V, that they felt the Moon race was over.
Host: We’re now 50 years past that moment. Can you tell me what you’re thinking now 50 years later?
Harrison Schmitt: Well, I feel the same way. I think not only was it extraordinarily important to the winning of the Cold War, to the collapse of the then Soviet Union, but now it offers lessons to us as we enter into a period of time where we may, and I think do have another Cold War, primarily in competition with China. And the Apollo program is an example for NASA or some other agency that may come into existence on how to compete in space, in deep space, how to manage the risks of deep space, and how to create a management environment where things can happen very, very quickly, and you can make milestones.
Host: Going back to post Apollo 11 landing, I’m sure after witnessing Neil Armstrong and Buzz Aldrin on the Moon, you had some ideas from a geological standpoint of what was important and how to conduct science and look for the right samples. Can you tell me about some of your work moving forward from Apollo 11 to your mission, Apollo 17, where you were training other astronauts in preparing yourself for those missions?
Harrison Schmitt: Well, all of that preparation actually began before I even applied for the astronaut program. It goes back to having been able to work with Eugene Shoemaker in the U.S. geological surveys activities that related to Apollo. They were on NASA contracts to think exactly about those issues, of not only how would you do science on the Moon, but what science would be important? In fact, I even planned a lunar traverse, hypothetical traverse, using the Ranger pictures from the Ranger program, the last image of the Moon that Ranger provided before it crashed into the Moon. I did a traverse plan was published, and was I think the first traverse plan that was ever done. And after Apollo 11, and once we knew that in broad strokes what we were dealing with in terms of the age of the Moon, the variety of lunar rocks that we might see, what may have been the evolutionary sequence of the Moon as a small planet, that then started to get everybody thinking, not only myself, but many others, about how to gather more information, more detailed information about the Moon and how it, how it relates to the Earth. Again, the Earth was our primary focus, that early history of the Earth that is obscure to us down here on Earth because of the dynamic processes that take place geologically here versus the very quiet activity of the Moon, at least in the last three and a half billion years.
Host: Now, jumping forward to Apollo 17, in what way, in what ways were you essentially practicing and studying for your mission?
Harrison Schmitt: Well, Apollo 17 training actually began when I worked with Dick Gordon as a backup crew member for the Apollo 15 mission to the Moon. And that was really the beginning of my intense training. 15 months of training, then 15 months of training for Apollo 17. And most of that training, of course, had to do with flying the spacecraft, and carrying out the actual operational plan for the Apollo 17 mission. In addition, because of the training program that I had put together for the Apollo 13 crew, and that continued on for the other missions, we spent about a week a month actually out in the field working on geological problems, but getting used to using the equipment that we would have on the surface.
Host: Now, again, just prior to Apollo 17, you putting your own boots on the Moon, tell me about some of the top lessons and strategies you learned from some of your other fellow Apollo astronauts who previously walked on the Moon. What were they telling you on how to be successful?
Harrison Schmitt: Well, the main thing that we learned from all the crews is that time is relentless, that you never have enough time to do what you want to do. And no matter how conservative you make the flight plan, you run out of time. It’s just the way space is. And it’s, in fact, it’s the way life is. But it is focused and concentrated in space more than normally is the case here on Earth. And so we tried to put together flight plans, our EVA plans, particularly, that understood that you would never have enough time to do things. And for Apollo 17, because we had a geologist, a field geologist, that’s very important distinction, is someone who’s used to sizing up a geological situation quickly using their experience to do that, and then focusing on what appears to be important at that particular location. And so for Apollo 17, we tried to open up the timeline so I would have enough time to do that while the commander was actually doing the housekeeping part of taking care of the Lunar Rover and other things like that. And then once that was complete, then the two of us could focus as a team, and very important to work as a team, for sampling and photography and the like, on what seemed to be the best approach to gathering the most information we could from any particular station that we would stop at on Apollo 17.
Host: Now, referring back to your training, you said most of your training was, of course, for the operations of the whole thing. Focusing specifically on the lunar module, can you tell me about that experience, training in the lunar module and learning to pilot it for your mission?
Harrison Schmitt: Well, the lunar module was a remarkable vehicle. It, of course, was designed to work in space, not in an atmosphere, it was very lightweight compared to what you would expect a spacecraft to be. Certainly anything that Buck Rogers had would not work very well on the Moon because of the mass. And so the lunar module was an extraordinary challenge. And the workers at Grumman Aircraft Corporation at the time did a remarkable job in developing it, as well as the NASA engineers who oversaw their work, and who figured out in the final analysis how to get the weight to a point, the mass of the lunar module to a point of where it could actually land on the Moon, given the kind of energy that the Saturn V had to place it there. So, it was a remarkable vehicle. It could do many things. Obviously, we used the computer. It was a very primitive computer, but one that did the job extremely well. And one thing you have to remember, that that computer was tied through telemetry to larger computers, much larger computers, IBM computers here on Earth. And so when we made a measurement using say a telescope or something like that in the lunar module, or in the Command Module, that information came back and was processed down here on Earth. And then the results of that processing was put into our guidance system in the two spacecraft. So, it was a cooperative thing between the space, between space and mission control, very important cooperative activity. One of the things, though, that for our mission that I think was unique, I know it was unique, is that we were able to figure out, I worked with the engineers who had developed the abort guidance system, which was a different kind of computer, much less precise than the primary guidance and navigation [control] system that we had, the PGNCS, but I worked with a way in which we could get an altitude update during landing, during the final approach to the surface of the Moon, get an altitude update in the abort guidance system, so that if we had to, we could probably have landed using the aboard guidance system if the primary system had failed. We didn’t have to use that, but that was different about the Challenger operation than any other mission is that, with the help of these engineers, I had figured out how to get an altitude update into my computer. The aboard guidance system was a computer that I ran.
Host: Well, tell me about some of the, some of the challenges, being a geologist by training, to learn these systems, compared to some of the test pilot astronauts.
Harrison Schmitt: Well, it turns out that test pilots and geologists are very much alike. They, they have to be good observers. They have to have a background in a wide variety of scientific disciplines. Clearly, the test pilots did not know the geological vocabulary. And so we kept that as very simple, very simple as possible. But, and clearly geologists didn’t know how to, how to fly an airplane. Most of us didn’t. And so that was, the main thing was to bring these two groups together using their complementary talents, and actually end up with pilots who were good field geologists, and a field geologist who was a good pilot. And that really is I think a lesson for the future is that that’s the best way to operate. In fact, I would have every geologist that goes to Mars also be a jet pilot and a helicopter pilot I think is very, very important discipline, type of discipline to have learned, even though you learned it late in life.
Host: Now, jumping to you landing on the Moon for Apollo 17, tell me about your thoughts, suiting up and taking those first steps.
Harrison Schmitt: Well, you get so focused on following the timeline, making sure that you maximize the use of the taxpayers’ time that you have on the Moon, that you don’t, I didn’t think very much about what was going on other than to make sure that we were getting out and getting to work. And in retrospect, you file away these impressions. But I didn’t stand around and say ooh and ah very much on the lunar surface. But we landed in a valley deeper than the Grand Canyon, as I said before. And it’s really a magnificent place. The mountains on either side went to 1,600 on one on the north to 2,200 meters above the valley floor. It was brilliantly illuminated by the sun. But the unusual, two unusual things was that anytime you looked up into this blacker than black sky, you could see the Earth. And a really remarkable experience.
Host: Now, tell me about your, your mission priorities as a geologist. Now you said you were focused in trying to stick to the timeline. But you wanted to free up your time so that you could survey and use your eye to look at the more interesting parts. Tell me about your priorities.
Harrison Schmitt: Well, we had, with the help of many people, had put together what turns out to be an excellent plan using the limited photography we had of the landing site. Today, of course, we have Lunar Reconnaissance Orbiter images of the landing site, which are, if we had had them at the time, you stand back and say, “would I have changed the flight plan?” Well, actually, it turns out, I don’t think I would have, based even on the information we have today. But we have learned so much from the samples and the photography that we’ve just been able to enhance and grow from the information that we collected. But, and the priorities that we had established for the Apollo 17 mission was to take advantage of that three dimensional situation we were in to sample boulders that had rolled off these high mountains, to look at an avalanche deposit that had come off of one of them. And the whole area seemed to be covered by some dark material that we had thought would be volcanic ash. Turns out it was, but we did not expect in one of the great discoveries of Apollo 17 was to actually find a deposit, a relatively undisturbed deposit of this volcanic ash, the so called orange soil. It is actually orange and black. Most of it was black, but the top part of it was orange. And that discovery has turned out to be one of the primary discoveries related to the Moon and the Earth in that it tells us more about the origin of the Moon. It tells us about the presence of volatiles and indigenous water inside the Moon. And it tells us about the processes by which these, what we call pyroclastic volatile driven eruptions occur on the Moon. Anybody who watched the news about Hawaii knows what a pyroclastic eruption looks like. A very violent kind of thing. On the Moon, that has happened in 1/6th gravity. And so they’re even more spectacular, or were more spectacular three and a half billion years ago.
Host: Yeah. You know, looking back at that time, looking at all these different samples, is there a particular moment you remember retrieving a sample or something you, maybe something unexpected that you remember doing in one of your EVAs?
Harrison Schmitt: Well, almost every sample was unexpected because we couldn’t see that resolution. And so you pick a place where you think you’re going to find something interesting, and indeed, every place we picked did have things that were interesting. And I mentioned the orange soil, the volcanic ash that we discovered. That probably was the highlight of at least that particular EVA, the second EVA. But every mission, and I continue to work on these samples, and the work, and not so much on the samples, but what other people have done to analyze the samples and try to synthesize that information into a more, into a coherent picture of what actually happened on the Moon, and how it relates to the origin of the Moon, and indeed, to the history of the Earth.
Host: So, tell me about the, some of the other experiments that were happening during Apollo 17. There was a, there was a light flash experiment looking at cosmic rays, gravimeters, some of these other experiments.
Harrison Schmitt: We had a wide variety of geophysical experiments that we put out on the Moon. We deployed an active seismic experiment, which were actually charges of the largest one was about six pounds of TNT equipment we deployed these. And they were activated, of course, after we left, and not before. I had, I deployed almost all of them, and I had to pull three– pins to activate timers that would allow them to be exploded 90 hours after they were activated. And so there was plenty of margin there. But still, you have six pounds of TNT in your hand, and you’re pulling pins on it, that’s an interesting psychological thing to be doing. We also had a traverse gravimeter experiment. So, we measured the lunar gravity at every site where we stopped. And then some. That information has been refined recently using the laser altimetry from the Lunar Reconnaissance Orbiter spacecraft, so that it is even better now than it was when we gathered it. Same, same data, but it’s been refined using that new information. We also had a lunar surface gravimeter, just a steady gravimeter that was designed to measure what’s called the free oscillations of the Moon. The Earth and the Moon both have free oscillations if they’re activated by an earthquake or a moonquake. But also they would be activated by gravity waves coming by. So, it was the first real attempt to measure gravity waves, to see if gravity waves really existed. We now know that they do. That’s been a very important experiment that that’s been conducted here on Earth. But at the time, the idea was to use the Earth and the Moon as a big oscillator in space. And so if a gravity wave went by, it would activate both of them at the same time. That, unfortunately, that experiment did not work. But, nevertheless, the idea was there, an extremely important idea to try to verify Einstein’s hypotheses about gravity.
Host: Right. Now, a lot of these experiment, you’re saying, understanding more about the Moon helps us to understand Earth, which is extremely important. There’s some physics aspects to what you’re studying. Can any of this be applied to future exploration knowing what it would be like to, if we were to live on the Moon for extended period of times, any of this data relevant to maybe those missions in the future?
Harrison Schmitt: The main data that we have now about the Moon that’s relevant to future settlements, future activities on the Moon, is that that comes from the soils, the lunar soils, because those soils have been gathering the resources of the Moon that are put out as part of the solar wind. There’s hydrogen, there’s nitrogen carbon principally. And with hydrogen, you can always make water and extract oxygen then from the rocks themselves. So, for the future, our primary knowledge that we have gathered has been from the soils of the Moon. And as I indicated earlier, there is a light isotope of helium called Helium 3 that is the only resource that we know about on the Moon that potentially can be of great value here on Earth. It is an ideal fuel for fusion power, produces no radioactive residuals of any kind, but produces electrical power at very high efficiency when fused with itself, or with the heavy isotope of hydrogen called deuterium. So, we have two great discoveries based on really what Neil Armstrong sampled as ten zero zero eight four, that soil that he filled up the rock box with, and that we know that we have resources that can support us when we decide to live on the Moon, and when we decide to go to Mars, and a single resource that may be of extraordinary value here on Earth, particularly as we try to wean ourselves from fossil fuels.
Host: Jumping back to your Apollo 17 mission, you spent three days on the surface. Can you tell me about actually living beyond the work itself? Did you establish a routine, or what was it like to actually live there for a few days?
Harrison Schmitt: There’s almost never any routine when you’re on the Moon. Something always happens that disrupts the plan. For one thing, right, as soon as we, almost as soon as we landed, when we were having our first meal, well, the compartment where the meals were stored opened up, and the pressure from the atmosphere, the pressure in the bags had put enough pressure on the door of that compartment that when we opened it up, all the meals came out into the cabin. So, we had to figure out a way to stuff all that back into the cabin. Also, you never can really experience 1/6th G continuously without being there. In fact, that’s the essential ingredient of the excitement of being on the Moon is being there. You can’t transfer that to you or to anybody else. You have to go there yourself. So, I hope you have that opportunity someday. But we of course knew how to swing our hammocks for sleep in the lunar. But until you actually do that and get in them, you don’t realize how comfortable 1/6th gravity can be. I slept extremely well on the Moon. I’d wake up about every two hours and listen to make sure that the fans and the pumps were all still running. You don’t want complete silence on the Moon, believe me. And then I’d go back to sleep. So, I slept very well. I can’t speak for the commander, I can’t, or anyone else, but I slept very well on the Moon.
Host: It’s almost like the routine was adaptability really just going with the–
Harrison Schmitt: That’s the essence of being a human being, is being able to adapt.
Host: Tell me about, particularly on your mission, you traveled pretty far in the Lunar Rover, the LRV. Can you tell me some of the advantages you had driving that distance, and really expanding your reach on the Moon?
Harrison Schmitt: Well, there was a great debate before the Lunar Rover was finally picked as a system for use on the Moon. Between having a driving machine and having a hopping machine. And that was an interesting debate. Chemists tend to favor hopping from place to place, because they just want a sample here and a sample there, sample there. A field geologist wants to see the context as you approach a particular sample site. You want to see how does everything else fit into that particular place. So, that debate went on among geologists and engineers as well. And Max Faget, who was the chief engineer down here at the manned spacecraft center, now Johnson Space Center, it, he finally just asked one question. He says, “how are you going to train to use a hopper?” And that pretty well settled that. It was going to be very difficult. We had been going through the lunar landing training vehicle experience for three, including Neil Armstrong, had to bail out of that machine, it was a very difficult thing to train with. The lunar module pilots finally were not trained in that because just the difficulties of using it. And so Max had a great deal of influence on whether we had a Lunar Rover or Lunar Hopper. Now, the Lunar Rover itself worked very well. We could go at about 10 or 12 kilometers an hour over most of the terrain that we drove on. It could, we drove up a 20 degree slope to get to Station 6, the big boulder there. So, it performed extremely well. It never, we never had any problem. There were little glitches on the other two missions, but we had never had any noticeable problem. The Boeing people, the Marshall people, the General Motors people all did a wonderful job in building, designing and building that particular vehicle. It really made a great deal of difference. The main contribution I think I made to operations of the Lunar Rover while for Apollo 17, was to develop a Rover sampler, which was basically a nested set of what we call Dixie cups. In a sampler, we could put on one of the extension handles. And I wouldn’t have to get off in order just to get a soil sample, or a small rock sample, just by reaching down. And those samples have turned out to be extremely valuable because they give a lot more context between stations of how were these soils of the area changing as we approached different sites.
Host: So, and you were able to do that because of the distance you can cover with the Rover.
Harrison Schmitt: Yeah, no question about it. We covered a total of about 32 kilometers with the Rover. The farthest we went away from the lunar module Challenger was about seven kilometers out to Station 2 at the base of the South Massif. It was the highest mountain in the area.
Host: Now, one of the things you mentioned about looking out onto the surface of the Moon, you mentioned the blackness of the sky, but you also mentioned that you can see the Earth. Can you tell me about seeing the Earth from the Moon, and some of your thoughts there?
Harrison Schmitt: I can’t really tell you. You’ve got to go there. [Laughter] It’s always in the same part of the sky because the Moon, as the Moon goes around the Earth, it keeps the same face towards the Earth. And so the Earth is always in the same part of the sky. If you’re right in the center of the Moon, it’s going to be directly above you. It was a little bit, it was down below that point a little bit for us. It was always over this high mountain, the South Massif. And so seeing that was really a remarkable experience in that black sky. And it’s primarily blue with white clouds, patterns that we’re familiar with. And the one thing that stands out on the Earth are the large desert areas, such as Australia, for example. Stands out almost as an orange beacon, even from the distance of the Moon, 250,000 miles from where we were.
Host: Reflecting on Apollo 17, can you tell me about your crewmates, Gene Cernan and Ron Evans?
Harrison Schmitt: Outstanding crewmates. I think I can say that for all the crews. For the most part, they worked together extremely well. Once assigned to a mission, they approached it very professionally. Not many of them were close friends, I don’t think, afterwards. I think the Apollo 12 crew was probably a good example of very close friends. But most of the people, just they were professional that came together as a crew, worked extremely well, and did extraordinarily great jobs on each of the missions. Now, Ron Evans I think probably knew the command module America better than anybody had ever known the command module. I was really very impressed with what Ron could do. He, and, of course, he had to spend three days alone in orbit around the Moon, but in that process, operated a wide variety of remote sensing instruments, as well as kept prepared in order to receive us should we have to leave the Moon in a hurry.
Host: Jumping to after Apollo 17, returning, you know, you were conducting all of these experiments, and you’ve already mentioned some of the findings from some of those experiments, some of the things you’ve discovered from doing geological surveys on the Moon. But can you tell me some of the things, some of the other highlights of the things you learned during your stay?
Harrison Schmitt: Well, just recently, we’ve been able to take the nitrogen isotopes that are in the deep core of the, that we obtained on Apollo 17, take the data from those nitrogen isotopes and look like we have found a major change in solar activity just about 500 million years ago. We’re still working on that. But it looks like something strange happened to the sun. It increased its luminosity, the amount of energy that was coming from the sun. About 500 million years ago. And one of the interesting things is on Earth, that’s when there was this explosion of life. We call it the Cambrian explosion about 550 million years ago. And most people said that was because the Earth was warmer. Well, maybe it was warmer because the sun changed its way of operating. That’s the kind of thing we’re working on right now today. And it’s made possible, in large part, because of the advance of analytical technology. What we do today compared to what we could do 50 years ago with these samples is almost night and day. It’s really amazing. It’s like the discovery of water in the ash, the orange ash that I sampled. That was done first in 2008. We never, we thought up until that time that the Moon was bone dry, that there was no water. We knew there were other volatiles, but no water. Well, now we know there’s water inside the Moon. And that, in turn, standards to open up your thinking about what about the ice that we think we’ve discovered at the poles of the Moon? Is that old water that came out as volcanic eruptions, or is it new water that’s been formed by some other process? We’re having a lot of exciting times in the lunar science community right now.
Host: And that, that brings up a good point, is even after your mission, you’ve still stayed very connected to studying the Moon and trying to uncover its secrets. Can you tell me a little bit about that, your continuing involvement with science on the Moon?
Harrison Schmitt: Well, I’ve tried, since I left the United States Senate, I’ve tried to get back in the game, so to speak, and I give a paper two or three a year at various science conferences. And I try to publish also just recently two years ago, my colleagues and I published a paper called “Revisiting Apollo,” Taurus-Littrow, the Apollo 17 landing site. And we didn’t get all the way through that revisit, but that’s still in work. There are other papers now that they’re drafting and trying. But the main thing I’ve tried to do is synthesize everything that other people have done. And that is a very exciting thing to do. I don’t– I’m also involved in one of the sample analysis teams that’s going to look at these samples that have never been opened that NASA has recently decided they would open. Core 2 from our Station 3, Apollo 17 Station 3 on, on the– that large avalanche that I mentioned. That I’m working with the University of New Mexico scientist Chip Shearer who will be the lead of our team. It will be a multidisciplinary investigation of these unopened samples. So, that’s an exciting thing to do as well.
Host: It’s quite amazing about how many, you know, all these samples we collected from Apollo that we still continue to investigate and find out new things along the way. Why do you think that is? Is it a little bit because of technology, or why do you think we are continuing to learn?
Harrison Schmitt: Well, it’s several things. It’s, technology certainly is giving us new tools. But people have learned a lot. They’re thinking differently. They come up with new ideas and the like. I think it’s a combination of that. And it’s been extremely active community for 50 years. And there’s no indication that it’s not going to be active for another 50 years at least. Again, people have said that the samples are the gift that keeps on giving. And there’s no question that that’s the case.
Host: Now, you were there when President Trump signed Space Policy Directive 1. Can you tell me about that experience?
Harrison Schmitt: Well, it was great to see the president take personal responsibility for getting us back into deep space. The vice president certainly has played a tremendous role in that effort. The reactivation of the National Space Council is very important. They also now have a user advisory group on which I serve, as well as a number of other people from around the country. And so it’s a very active policy time right now. The big question is can NASA reorganize itself so it can actually carry out that directive? And we don’t know the answer to that yet. NASA is not the NASA of Apollo. It’s older. It’s more bureaucratic. And it has its own heritage that it has to either, let’s say it has to deal with. And so we’re still waiting to see whether now NASA can implement a very aggressive program that was recently put forward by the vice president on behalf of the president that we get boots on the Moon again by 2024. And that’s extremely important we do that. As I indicated earlier, we’re in another Cold War that I think the administration does recognize that, and it’s important that we be not only a competitor in that effort, but also that we succeed and are successful in that effort.
Host: And that is a bold claim. Boots on the Moon by 2024. Part of that plan is to move forward to a sustainable presence. Right now, I think the goal is 2028 to have a sustainable presence on the Moon. Can you tell me about what a sustainable presence on the Moon would mean from a geological perspective? What are the benefits of doing that?
Harrison Schmitt: Well, if you establish yourself in a sustained base or settlement, I like to think of a settlement, not only to harvest the energy resources of the Moon, the Helium 3, but to, as byproducts, have the resources necessary to go onto Mars. Then geologically, you’re going to learn about another planet eventually. Namely, Mars. But also it provides a base of operations for the exploration of the Moon. You don’t have to always launch from Earth to explore a new part of the Moon. You can launch from that base to go to anywhere on the Moon really and conduct those geological studies. The main thing that studying the Moon gives us about the Earth, one of the things we already have, and that is we know now that the early history of the Earth was extremely violent. There were major, huge impacts happening not only on the Moon, but on the Earth. And at the same time, though, life was getting a start. The complex molecules were getting organized, and ultimately became replicating molecules that led us to life. And the more we can understand the Moon in that period of time, the better we’re going to understand the origins of life here on Earth.
Host: Well, looking forward to going back to the Moon, or sorry, forward to the Moon. What are some of the more interesting places? Do you have some locations in mind of what would be probably more interesting to explore or to, like you said, settle?
Harrison Schmitt: Well, the largest basin on the Moon, the largest impact produced basin on the Moon, is almost certainly about 3,200 kilometers in diameter. It’s called the Procellarum basin. That’s continental in scale here on Earth. That would cover the entire United States. The one basin that everybody agrees occurred is 2,500 kilometers in diameter, also continental in scale, and it may be in these very large basins we have the origin of the continents. We don’t know that yet, but that’s a possibility, that a variety of things happen in order to see the continents after these large basins formed. The main issue I think, though, is to start to sample the materials of these basins. And the one large basin that I mentioned, 3,200 kilometers in diameter, Procellarum, is so old that it’s going to be very difficult to know that that’s what you’re sampling. In fact, I think we’ve already gotten samples from Procellarum, but that’s a different story. That, the geologic context of Procellarum is going to be very difficult. Whereas South Pole-Aitken, the other basin, 2,500 kilometers in diameter, is still well defined. And if we do our planning right, I think we can not only learn about the materials produced by such large impacts, but we may actually be able to get samples of the lunar mantle from the center of that crater. That crater floor is 12 kilometers below the mean lunar radius. So, it’s a very deep basin, as well as a very large basin. And that probably right now is the site, the South Pole-Aitken is where I and most other people I think would like to go. And that’s where the Chinese have landed, by the way. They’re not, they’re not very far behind us in that respect.
Host: It’s an interesting place, for sure. So, a sustainable presence. Can you tell me about what that opens up to the scientific community? I think you’ve already mentioned sample returns, more sample returns, possibly better technology. What does this open up?
Harrison Schmitt: Well, having a base on the Moon, again, gives you access to the entire Moon, scientifically. It also, though, allows you to look at things in situ that is in place. For example, we cannot produce a simulate of lunar soil here on Earth that is a true simulate. We can produce certain aspects of it and learn from those aspects. But you cannot produce a two simulate because those, the lunar soils are forming in a vacuum. That is as hard as deep space vacuum. Ten to the minus 12 torr if you’re into the nomenclature of vacuums. It is really impossible not to be able to understand the processes that are operating in the lunar environment without being there and actually working in situ, in place, with those materials. So, that’s probably one of the major things. And also we’re just now starting to understand how the history of the sun can be deciphered from the lunar soils. And that’s going to be difficult. But I think we’re now finally, we’ve talked about it for well over 50 years, that the Moon is recording the history of the sun. And now, though, we’re finally, with the data we have, with the analytical techniques that we have, beginning to understand what we ought to be looking for. But getting more pages out of that history book from different parts of the Moon is going to be extremely important if we really want to understand the long term history of the sun.
Host: Now, aside from the physical science, the geological science of the sustainable presence on the Moon, what else is important for establishing that presence?
Harrison Schmitt: I think the main thing that’s important is for it to have an economic reason to exist. And that’s where this Helium 3 fusion power comes in. If, indeed, Helium 3 fusion can be developed here on Earth as a commercially viable source of electrical power, then a settlement on the Moon has an economic reason to exist. And I feel actually confident that that’s going to happen someday. But, still, that needs to be established, and needs to be explored. And people are now looking at that very, very seriously. The technology is advancing to, that is related to Helium 3 fusion. That’s a very important thing, because I don’t think you’ll do much with it until you know for sure that there’s a commercially viable fusion reactor. Helium 3 is very rare here on Earth. It’s only produced by the decay of tritium that, and that is tritium that’s used in nuclear weapons. It has a half-life of 13 years, approximately. And so every 13 years or so, you have to clean up these weapons. And that’s the source of Helium 3. Helium 3 is also very important in use in neutron detectors. The Homeland Security Department uses it. And, in fact, it’s tied up most of the supply in order to be able to have detectors in our borders that can look for nuclear materials, clandestine nuclear materials coming into the country. So, there are a lot of challenges in developing Helium 3 fusion. But I think those can all be met in the long term. And that will probably be a sustaining economic reason to have a settlement, and maybe ultimately an independent settlement. Jefferson always used to say a little revolution is important every once in a while. And taxation of a lunar settlement without representation might just trigger that small revolution. And we would have a little settlement at another birth of freedom, if you will, on the Moon.
Host: Now, you’ve been a NASA astronaut. You’ve been close to the scientific community, especially studying the Moon, for years now. Can you tell me about, from your perspective, the benefits of human space exploration? Why is it important?
Harrison Schmitt: It’s important geopolitically for the United States to be very active in deep space. It’s important from a humanistic point of view to continue to challenge, for the human species to continue challenge itself against the frontiers, as it always has. I think it’s in our DNA to move into new areas, find new resources, new ways of sustaining our civilization. Those were probably the two most important things. One, geopolitical. And two, the continuation of the exercise of the human spirit against new frontiers.
Host: Now, I want to end on a little bit more of a fun note. Do you have any tips and tricks as a lunar explorer yourself for the future lunar astronauts?
Harrison Schmitt: Well, the main thing that you need to realize is working in 1/6th gravity is a lot of fun. I only weighed 1/6th of my total weight, including the spacesuit and a backpack and everything and I weighed 62 pounds. And so the suit is encumbering. We need much better suits. And I hope that NASA begins to invest in those suits very vigorously. But, nevertheless, the A7LB that we had for Apollo 17 worked extremely well. And remember that in 1/6th gravity, the whole surface is like a giant trampoline. It’s like walking on such a trampoline.
Host: Dr. Schmitt, I very much appreciate your time today. It was an honor to talk to you. Thank you very much.
Harrison Schmitt: It’s my pleasure. Thank you.
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Host: Hey, thanks for sticking around. Really good conversation we had with Dr. Harrison Schmitt about all things Apollo 17, science on the Moon, and what we have to look forward to. Really enjoyed having him here in our studio. If you’re excited about the 50th anniversary of the Apollo program, we have a great website where you can check out all of our materials, nasa.gov/apollo50th. We have a dedicated series of Apollo 50th anniversary episodes on our Houston We Have a Podcast page. Just navigate to there to see all of our collection of episodes. We have many other podcasts at NASA as well. So, just go to nasa.gov/podcasts to check them all out. If you’d like to talk to us, we are on the NASA Johnson Space Center pages of Facebook, Twitter, and Instagram. Just use the hashtag #AskNASA on your favorite platform to submit an idea for the show. Just make sure to mention it’s for Houston We Have a Podcast. This episode was recorded on April 15th, 2019. Thanks to Alex Perryman, Norah Moran, Pat Ryan, Belinda Pulido, and Stephanie Castillo. Thanks to Dr. Harrison Schmitt for taking the time out of his busy schedule to speak with us.