On December 11th, 1972, Apollo 17 crew members landed on the Moon's surface. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt stepped out of the lunar Lander challenger in the Taurus-Littrow Valley, near Camelot Crater. 49 years later, no other person has eclipsed their accomplishments and no one else has set foot on the Moon since then.
However, Schmitt and all those excited by the idea of space travel and exploration are looking forward to that fact changing very soon. With NASA preparing to return astronauts to the Moon as soon as 2025, commercial space travel becoming a reality and plans to study exoplanets across the galaxy, a new era of space exploration is just over the horizon.
Discover Science: Harrison Schmitt on his trip to the Moon
Apollo 17 astronaut Harrison Schmitt discusses his three days on the lunar surface, the exciting geological discoveries that he made as the only true scientist to have set foot on the Moon and his thoughts on the future of space exploration.
This episode of Discover Science welcomes Apollo 17 astronaut Harrison Schmitt. The podcast hosts are Paul McFarlane, director of the Fleischmann Planetarium and Science Center, and Wendy Calvin, the Daniel A. and Edith E. O'Keefe Professor for the Mackay School. Calvin is also a University Foundation Professor, a member of NASA's Mars Exploration Rover science team and has studied planets and moons for much of her career. The three discuss Schmitt's three days on the lunar surface, the exciting geological discoveries that he made as the only true scientist to have set foot on the Moon and his thoughts on the future of space exploration.
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[recording of Apollo 17 mission]
Paul McFarlane:
On December 11th, 1972, Apollo 17 crew members landed on our Moon surface. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt stepped out of the lunar Lander challenger in the Taurus-Littrow Valley, near Camelot Crater. What you just heard were these two astronauts singing together as they explored the lunar surface. 49 years later, no other person has eclipsed their accomplishments and no one else has set foot on the Moon since then.
Paul McFarlane:
However, Schmitt and all of us excited by the idea of space travel and exploration are looking forward to that fact changing very soon. With NASA preparing to return astronauts to the Moon as soon as 2025, commercial space travel becoming a reality and plans to study exoplanets across the galaxy. An era of space exploration we can hardly even comprehend is just over the horizon. I'm Paul McFarlane, Director of the Fleischmann Planetarium and Science Center. Here with my wonderful co-host Wendy Calvin, the O'Keefe Professor for the Mackay School, Foundation Professor and Chair of the Department of Geological Sciences and Engineering. Wendy is a member of NASA's Mars Exploration Rover science team and has studied planets and Moons for much of her illustrious career.
Wendy Calvin:
Thank you Paul. On this episode of Discover Science, we are thrilled to be speaking with astronaut Harrison Schmitt about his three days on the lunar surface, the exciting geological discoveries that he made as the only true scientist to have set foot on the Moon and his thoughts about the future of space exploration. Welcome, Dr. Schmitt.
Harrison Schmitt:
Thank you very much. It's great to be here.
Paul McFarlane:
Well, I know many of our students are curious about what it would be like to actually be on the Moon. Only 12 people have ever visited. If you were going to describe that experience, could you share that?
Harrison Schmitt:
Well first, just understand what your constraints are, whether you start with the constraint of time. Time is relentless as my backup commander on 15 used to say Dick Gordon. And secondly, that is made more relentless by the space suit. The Apollo space suit that we had, the last three missions had what was called A7LB space suit, much more capable than what Neil Armstrong had, but never nevertheless, it was constraining you couldn't act normally in it. We also had on the positive side, a Block II Lunar Module. You had to in order to use that suit because you needed more oxygen. It had a really an eight-hour capability rather than a four, which the original suits had. And one of the big things you needed was cooling water. If you didn't have water-cooled underwear, you wouldn't be able to work very long on the Moon.
Harrison Schmitt:
If you relied on gas cooling, it would not have worked very much, but the A7LB space suit was really very capable but still constraining. And the other thing you have to remember, you're working in one-sixth gravity, one-sixth of earth's gravity, and that can be a blessing and a constraint as well. It means that you don't get as physically tired as you would here on earth and would in that suit, but it also means that you have to be very careful about where your center of gravity is.
Harrison Schmitt:
The backpack we had moved the center of gravity of the combined body and backpack about two inches to the rear. And if you look at films, you'll see astronauts Buzz Alden, or almost anybody leaning forward. Well, that's to get the center of gravity over your feet. But then if you get into a dynamic situation, such as I did in trying in helping Gene Cernan extract the core, you can forget that you will rotate around that center of gravity if you get too vigorous. I found that moving across the surface at any distance, was best accomplished by applying what I call a cross-country skiing technique. And as a Fulbright student in Norway, I had taken up cross-country skiing and it just is a very efficient way to move across the snow. Well, on the Moon, you glide above the surface and use your toe to just accelerate a little bit. And without any atmosphere or any friction on the surface, you can keep accelerating as long as you can coordinate that toe push.
Harrison Schmitt:
And some of the pictures that you see, you see me using that technique particularly laid in the EVA, coming from station nine through a Boulder field is really a good illustration of how cross-country skiing works on the Moon. I never could convince my colleagues that this was a more efficient way to do it. But I hope in the future that people realize that rather than hopping or just trying to run, there are more efficient ways-
Wendy Calvin:
Ski technique. Well, you probably didn't anticipate that a ski technique you learned in grad school was going to be useful on the move.
Harrison Schmitt:
No, I really didn't anticipate doing it until I was there and realized that it was the best way to move. We worked on three EVAs for about, extra vehicular activities, we worked for about seven and a half hours full speed before we got into the, actually started to repressurize the Lunar Module. There was a reserve as you might expect in case, say, there were any problems. But we ended up with a total of over 22 hours of expiration time. Doesn't sound like much, maybe, but I'll tell you in lunar terms, I was able to get an awful lot done. We brought back 250 pounds of soil and rocks. Every time I sit down and start to work on the synthesis project that I have, I come across something new that I could tie together. And it's just really, really this amazing sample collection, amazing sample collection.
Paul McFarlane:
Before I forget, I was going to ask because we were talking about coming in from the EVA and all those things. We've heard that when you were taking off the space suits, you could smell the Moon. Is that correct? Was there a distinct smell of the-
Harrison Schmitt:
Yes, the fine particles of the lunar regolith, and they are very fine. I have an aroma very much like spent gun powder. Everybody had the same impression. And I think it's because they're not fully deactivated yet. It's like activated carbon. And it hasn't absorbed enough of the moisture and the oxygen in the cabin to cease to activate all factory senses. And so it has that same kind of smell like spent gun power.
Paul McFarlane:
Wow.
Harrison Schmitt:
Freshly spent gun power.
Paul McFarlane:
And there's all kinds of different questions, but I guess I'm curious, what were you most excited about during this adventure that you participated in?
Harrison Schmitt:
Well, of course I had been involved in the preparation of the other crews for all emissions. In fact, after my pilot training in 1966 was complete and I was in residence then at the Manned Spacecraft Center in Houston, I was able to really take a hard look at their training program for lunar exploration. And I already was pretty much aware of what was being done. And it was basically show and tell Ge1 field trips. And that wasn't in my mind going to be sufficient for the true exploration of the Moon and for getting a very broad spectrum of samples back.
Harrison Schmitt:
And so I put together a proposal and took it to Alan Shepard who was my boss at the time and said, "Let's do a simulation based training. Let's go out on real geological problems once a month." Spend four or five days with the equipment that they would have on their mission and have each crew then begin to absorb real geology and the techniques for actual exploration. And he said, "Well, if you can convince Jim Lovell" ... Who was up next for Apollo 13, "... to be the Guinea pig for this program, then fine." I went to Jim and Jim was very enthusiastic.
Harrison Schmitt:
As you know Apollo 13 did not land on the Moon, but he was very enthusiastic about the training. And he and Fred Hayes joined professor Lee Silver as their mentor, which I asked Lee to join in to this program. Part of the program was to have each crew have an outside mentor and who was an outstanding field geologist. And we went out for a full week in the Orocopia Mountains of California without phones, without any contact and just had these guys absorb what geology was all about and how to observe, what to observe, how to make decisions on what might be important and what wouldn't be important. That was the whole objective of it.
Harrison Schmitt:
And Jim Lovell and Fred Hayes became very enthusiastic and it turns out their backup crew was John Young and Charlie Duke who eventually flew on Apollo 16. And so four of the people who were going to land on the Moon were part of that initial program. It worked out very well. And when you look at the 850 pounds of lunar rocks that were brought back by the astronauts, we have a gift that just keeps on giving. And as you are probably aware, NASA just released some of the samples that had been frozen for 50 years-
Wendy Calvin:
Yep.
Harrison Schmitt:
... for analysis. I'm involved in that with the University of New Mexico and the leader of that whole effort is at the University of Mexico, Charles Shearer. We are in the process of not only looking at all the frozen samples but in particular, a drive tube core of 70 centimeters length. That half of which was frozen, that I took in an avalanche deposit, a dust avalanche deposit at near the base of one of the highest mountains in the valley area. ÍƼöÐÓ°ÉÔ´´ 2000 meters high. Really, we were in a valley deeper than the Grand Canyon and really a magnificent place to be. But the sample collection continues to be remarkable.
Wendy Calvin:
And what new things are you seeing? I know that there's just been a huge revolution in the technology and the instrumentation and the high-resolution stuff we can do now. Are you seeing new and interesting things in these-
Harrison Schmitt:
Yes. Very much so far. The effort's been going on now for a couple of years. We just opened up the drive-tube core. People assume that the core was one unit and with some variability in it. Well, it turns out it's probably 14 units that can be identified specifically on the basis of their different maturities, different petrographic characteristics-
Wendy Calvin:
So it's not just-
Harrison Schmitt:
... their chemical composition.
Wendy Calvin:
... the a brecciation of the surface, it's actually-
Harrison Schmitt:
No, it's not just brecciation of the surface, that's minor.
Wendy Calvin:
Huh.
Harrison Schmitt:
What has happened is that impacts elsewhere have sent ejecta over that is overlayed. And so you've got-
Wendy Calvin:
So you see multiple ejector layers?
Harrison Schmitt:
... a library of lunar history that turns out it's probably about 2 billion years long.
Wendy Calvin:
Interesting. Did your approach or understanding to field geology change once you were on the Moon or did you feel that the field training programs that you had provided for the astronauts were good or good enough for them to actually do decent field geology without being geologists?
Harrison Schmitt:
The main thing we were trying to get instilled in the cruise was how to recognize diversity and important diversity. And I think in that it worked because the sample collection is really a remarkable collection. It depended somewhat on individual talents. Neil Armstrong was absolutely fantastic as an observer. In 20 minutes, he probably brought back the best collection of samples per unit time of anybody, including myself. And one of his samples, which was soil he collected because he thought, as he said that the rock box looked a little empty after he put rocks in it. And he just filled it up with-
Wendy Calvin:
He just filled it up with lunar soil.
Harrison Schmitt:
... lunar soil. And that particular sample 10084, a lot of us know, is what is the foundation for understanding the resource potential of the Moon? The analysis of that sample has given us an understanding of how the solo wind volatiles are contained in the lunar surface hydrogen, from which then you can extract water from the silicates. But also it is told us about this remarkable light isotope of helium called helium-3, that is potentially an answer to the long term, clean electrical power needs of the earth.
Harrison Schmitt:
Energy is what's going to drive civilization one way or the other. Either you have it and you're going to progress, you don't have it you're going to go backward. And the Moon does offer us now a way of having clean energy, what we call aneutronic energy, that is fusion energy that doesn't produce neutrons. The neutrons are the bad actors, they create the radioactive waves.
Wendy Calvin:
Is that what you see as the primary resource for the Moon?
Harrison Schmitt:
Well, it's-
Wendy Calvin:
These days it's a lot about the water, so how do we sustain crews and astronauts as we think about sending people there?
Harrison Schmitt:
I think water is important, no question about it. You can derive oxygen from water. You can make water anywhere on the Moon. You don't have to go to the poles to make water, to get water. If you heat the regular if you're going to get water, hydrogen will react with the silicates and you'll get water. Water is going to be very important for long-term sustainability on the Moon. And if you're going to have actually transfer civilization to the Moon, you're going to have to make water.
Harrison Schmitt:
The helium-3 is probably the only resource we've identified so far that will pay to bring back to earth. There's very little helium-three on earth, certainly, almost none left over from the formation of the earth. It was rare to begin with and then it's not practically even think about that. But the heating through we have for research today, and for neutron detectors at our borders is derived from the decay of tritium, which is a product of nuclear fission and is used in nuclear weapons.
Harrison Schmitt:
Tritium decays over a period of about a little less than 13 years and after a while, you got to clean up your weapon or it's not going to be effective. And by cleaning it up, you get some helium-3. There's some also produced in Canadian reactors. They have a particularly heavy water reactor technology that produces some helium-3, but the amount is really nowhere near what you need in order to have power. It's nowhere near what you would need in order to use helium-3 as a way of getting very high-resolution lung images. You can polarize helium-3 and inhale it and then when it depolarizes, you get a very fine image of the lungs.
Harrison Schmitt:
Most people don't realize that only 19% or so of people who are diagnosed with lung cancer survive. If you can get early detection that jumps up into the 90s, and that's what helium-3 would allow you to do is get early detection of lung cancer. Now, there is a companion element called xenon-129 that you also can polarize. And that's being used instead of helium today because helium-3 just isn't available. But it does a different thing. It gets into the bloodstream into the capillaries. And so you see a different aspect of lung characteristics with xenon-129. The combination would just be remarkable in terms of detecting lung cancer.
Paul McFarlane:
Well certainly in your book Return to the Moon, you explained a lot of benefits that would drive from returning to the Moon and tapping into the helium-3, the energy generation or that solar power or the fusion or all the different possibilities. I'm curious with that film that maybe some of our listeners have seen Duncan Jones film, Moon, they talk about mining helium-3 and using that, sending it back with the rail gun. Are there real benefits for the earth that is described in that film or what you're describing here?
Harrison Schmitt:
Well, conceptually, the film is right on the mark. Technically the miners are a little too big. But the film really is a psychological film more than it is a technical film. And I highly recommend it. I think it's a great film. Another film that most people may not be aware of that's centered in Australia is the film Dish. Have you ever seen that?
Paul McFarlane:
Yes.
Harrison Schmitt:
It's about one of the communication antennas. It's really quite good. No, I'm a great fan of the Moon is a good film, but it also has an interesting psychological message with it and we won't give it away.
Paul McFarlane:
That's right. Keep the secret on that one. Well, there's such a range of things I know with the benefits in returning to the Moon are immense. We had a teacher at our school that wanted to know, why do we want to go back to the Moon? And I know some Americans wonder that too, and you begin to unfold some of the reasons here, and you've certainly done a very thorough job in your book. Why is that important in a variety of different ways, perhaps, maybe energy, maybe other ways?
Harrison Schmitt:
Well, the primary reason for the United States to be active on the Moon is geopolitical. And I wish it were otherwise, but that's a real fact of life. China is on the way, and there's no question they're going to try and probably will succeed in establishing themselves on the Moon. They're interested in helium-3, they've said they were as an energy source. But it's a geopolitical issue. Space is part of Apollo. It was for Apollo and it still is. The Apollo program was a creature of the cold war. And I hope everybody recognizes that. It's just also, you should recognize that there was leadership in and out of NASA that knew that if you had the capability to land on the Moon and to get outside of spacecraft, you had the capability of exploring and developing great scientific insight, not only about the Moon but about the early history of the earth.
Harrison Schmitt:
We now really do I think understand the environment in which life began on earth. And that's only because we now see what happened on the Moon. And we also may well be on the way to doing something Gene Shoemaker always said we were going to do, and that is decipher the history of the sun. And particularly now that I think I can demonstrate that the deep drill core is made up of individual regular projector units, which give you a book so to speak, several pages, 14 pages of a book of solar history.
Harrison Schmitt:
The only thing that is showing up so far in the synthesis that may indicate the history of the sun is in the nitrogen isotope ratios. And there's some indication that the sun went through a significant energy increase in the solar wind at any rate about 500 million years ago. And that is important to Earth's geologists because about a little over 500 million years ago, we had what's called a Cambrian explosion. And that's almost certainly due to a warming of the Earth's ocean to the point of where the diversity and the quantity of life really exploded-
Wendy Calvin:
Could really take off several.
Harrison Schmitt:
... over several tens of millions of years. But still we may now be able to see independent evidence of that happening because the sun increased its energy up.
Wendy Calvin:
I was going to come back to the geopolitics of the Moon because at the same time we're seeing a ton of new commercial interest and the Commercial Lunar Payloads Services Program, and so it's becoming not just countries anymore that are going to the Moon and wanting to go to the Moon. And so I wonder if you see a real lunar economy developing and if so, what would drive that what's going to make it profitable for commercial entities that also are now playing in the lunar game?
Harrison Schmitt:
That's an excellent question. The real difference between now and 50 years ago, is exactly what you say. There are entities you can may or may not want to call them commercial depends on how much government money is supporting them, but there's a lot of private money being invested in these companies and they see that the resources primarily to, I think their customer base is still being thought of as government space stations, spacecraft going to Mars that need oxygen, need water and that kind of thing. I think that's still driving it primarily.
Harrison Schmitt:
But nevertheless, that exists today where it didn't exist 50 years ago. There are rocket companies again with the government as their primary customer, but nevertheless, they have developed their capabilities by themselves. The SpaceX, Blue Origin and a few others that have not gone quite as far as those two. It is different, it's a challenge for NASA, is to figure out how do I integrate this explosion of commercial technology that has developed in a capitalistic marketplace? How do I integrate that with the geopolitical requirements that I have as a government agency and with responsibilities?
Paul McFarlane:
Well, I know as we were talking about the return to the Moon, many of us wondered we were getting excited about the Artemis program. What do you think about the prospects of NASA's upcoming return and what are your thoughts about Artemis or the next generation of explorers?
Harrison Schmitt:
Well, I think it's great that the Trump administration kicked that off and that it's continuing. Budgetary issues are still there. And I understand that some of the glowstone are slipping as they so often do. But still it's critically important from a geopolitical point of view that the United States participate in this space activity. The one thing that is missing in my opinion, and I talk about this in the book is a Saturn V class booster. The SpaceX booster, the Blue Origin boosters are fine, they're nice, but they are not Saturn class boosters.
Harrison Schmitt:
You cannot with one booster put a 37,000-pound payload called the Lunar Module on the surface of the Moon. We just don't have that capability. The Chinese have announced whether I don't know the details at all. There may not be any, but have announced that they're going for a Saturn class booster.
Wendy Calvin:
I guess I thought the Starship is-
Harrison Schmitt:
I think they read my chapter in the book.
Wendy Calvin:
I guess I thought the Starship was in that class, but maybe, I don't know SpacesX's launch of rockets.
Harrison Schmitt:
I would talk to Elon Musk about that, and he would probably claim that it is, but it only is if you refuel it in earth orbit 14 or more times. That's the difference. And which means that the risk management of a program that depends on Starship is much greater than it was even for the Saturn V and 50 years ago.
Wendy Calvin:
Because you're counting on those orbital assets to do the refueling and-
Harrison Schmitt:
You have to launch the fuel.
Paul McFarlane:
Well, certainly with an enterprise as big as going to the Moon, we need to involve the community. And it's an opportunity for all of us to learn more about our place and space. Why would you say community engagement is important and what are good ways for us to try to do more community engagement?
Harrison Schmitt:
Planetariums such as this are filling a gap that is huge or trying to fill a gap that is absolutely huge. And that gap has been produced by the deterioration of the public education system. The education of young people today with exceptions, there are some outstanding private schools, a few outstanding public schools, but the education today is horribly deficient in mathematics, in science, in history, language, you name it. And that is something that did not exist 50 years ago because we had a reservoir of young men and women, mostly young men at the time who had received obviously an education sufficient to do the job that President Kennedy put before us.
Harrison Schmitt:
There were over 400,000 Americans involved in Nepal, only 50,000 of them worked for NASA. And they were part in part what we call the Sputnik generation. There were young people who decided that they were excited to buy rockets and by engineering and making those rockets and launching them. One of the better books is the October, Scott. It describes some high school boys that decided to make rockets and the original title of that book by the way, was Rocket Boys.
Paul McFarlane:
And Anagram, they switched the letters around. Same letters, but different title.
Harrison Schmitt:
And an excellent movie, by the way. We're talking about movies. But you know, the level of preparedness of young people today is just abysmal compared to what is going to be required of them in the future. And the public education system just can't handle it right now.
Wendy Calvin:
I was going to ask, what do you see as opportunities and what could we put forward to those young students that might inspire them and get them to be interested in STEM careers? What opportunities are that you could say, "Hey, look, you could do this, but you're going to need some math and some science."
Harrison Schmitt:
I think hands on exciting projects is absolutely essential. That's really what we did with the astronaut training program. We gave them hands on things that exciting. Were much more exciting than just show and tell, a lecture. A long time ago, I proposed to the Boy Scouts with no effect that they have a part of their Explorer scout program be space scouts. And I tried to get NASA then to offer the opportunity through some kind of a selection process for some scouts to fly to the space station. And this was before there was a space station when we still thought we were going to have sky lab like stations. But the main thing, I think, young people, you have to develop things that they can't avoid being excited about.
Paul McFarlane:
Well, you're a crew member, a Commander Cernan and apparently would often say that he thought it would be wonderful see a teenager fly into space as a way to engage people. Well, that's not always financially possible or carries a number of risks, but what you're describing sounds like involving students in training like an astronaut or doing simulations or engaging them in real science like Dr. Calvin does with spectrometers. Are those the kinds of activities that you would recommend?
Harrison Schmitt:
You never know what's going to excite a young person. I know the space camp down at Huntsville does I think a good job from what I understand in that in getting people excited. But at the same time, they need to begin to understand why it's important to know more than they know right now, and particularly in math, but also in other areas.
Wendy Calvin:
And do you see that as part of your legacy is to have been a human example of somebody on the Moon to be inspiring in that way? Here's a person as opposed to just a Lunokhod robot driving around. Do you think that's an important piece of that inspiration?
Harrison Schmitt:
Well, I think it's important. I think it's what we astronauts can do and do, do. We have done through the last 50 years is to try to have outreach to the public and it works fairly well, reasonably well publicized event with an astronaut usually oversells like tonight-
Wendy Calvin:
Like tonight.
Harrison Schmitt:
But it's may unfortunately be a drop in the bucket of what has to be done. You just can't reach everyone and certainly can't reach all the students that need help.
Paul McFarlane:
Thank you Dr. Smith for coming here to the ÍƼöÐÓ°ÉÔ´´, for coming to the planetarium and for helping us all learn more about the Moon and our place and space. We really appreciate the honor of having you here.
Harrison Schmitt:
Well, thank you. It was great to get the invitation and I'm looking forward to more interaction.
[recording of Apollo 17 mission]
Gene Cernan:
And as we leave the Moon and Taurus-Littrow, we leave as we came and God willing as we still return with peace and hope for all mankind. Godspeed to the crew of Apollo 17.
Speaker 2:
All Roger Gene. Thank you very much.