The Apollo 15 Lunar Module Falcon touched down near the Hadley Rille at the foot of the moon's Apennine mountain range on July 30, 1971. David R. Scott and James B. Irwin were the first Astronauts to explore the moon with the help of a lunar rover, and they traveled more than 27 kilometers during their three lunar surface EVAs.

Careful practice and planning went into this lunar geological field trip. The two astronauts, both former test pilots, worked with field geologists to learn new skills and techniques, including the development of a unique vocabulary for describing the rocks to their dedicated EVA CapCom and the geologists monitoring the mission back on Earth. During their three-day stay, they collected approximately 77 kilograms of rocks and soil, including the more than 4 billion year old anorthosite sample, nicknamed "Genesis Rock."

While Scott and Irwin were on the surface, Alfred M. Worden flew solo aboard the Endeavour Command and Service Module orbiting the moon. Worden also trained with geologists, but concentrated on lunar observations and photography of the moon's surface. Back on Earth, Joseph P. Allen, one of NASA's scientist-astronauts, served as the lunar surface EVA CapCom.

Read below excerpts from oral history interviews conducted with the scientists and geologists who contributed to this mission's success.

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James W. Head, Geologist, Apollo Lunar Exploration Program
Interviewed June 6, 2002

That’s going to be a gold mine
We’d been very focused on explaining to the [Apollo 15] astronauts the question of was there any gas in the rocks as they came up from depth within the Moon. They undergo decreasing pressure, so it’s like opening a soda water bottle and gas starts to come out. It’s really a big mystery as to what was driving these volcanic eruptions, because gas is a big component of that on the Earth. So we kept telling them to be on special lookout for rocks with holes in them, because the gas, when the rocks cool and the gas is coming out, it’ll be vesicular, which means it just has a lot of holes in it from the gas, and if they saw one of those to get it. It’s sort of like the “Genesis Rock.” If you see something that looks like that, that’s going to be a gold mine.

They were coming back from an EVA, I forget which one, but they were told that it’s time [to get back to the Lunar Module]. Dave Scott said, “Houston, we’re having a problem with a seat belt. I’m just going to get off and adjust this thing.” I was sitting watching the seismometer, and it “zzzzzz,” stopped, and you can see it stop, and then they jump back on the [Lunar Rover] and say, “Okay.” Then it takes off. “Okay, we’re on the way back. It’s okay. Everything’s fixed.”

Well, it turned out what had happened was that Dave had been driving along, “Whoa! There it is! There’s a rock with all these holes in it. They’re not going to let us stop.” So they did this seat belt thing to convince Mission Control that they had to stop, and it worked. You know, it worked. That was pretty remarkable, because the rock was very important and just like the so-called Genesis Rock, in understanding many aspects of lunar science. So there was something. They knew what to look for. They knew how important it was.

If they’d said, “Hey, we’ve seen the vesicular rock that we’ve all been talking about. Can we stop and get it?” the answer probably still would have been no. But it worked. They were on the surface. They probably had a little better idea of whether they could drive a little faster on the way back.

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William R. Muehlberger, Geologist, Principal Investigator, Apollo Field Geology Expert
Interviewed November 9, 1999

It has big white rectangular crystals that are flashing at me
If you go into northern New Mexico near Taos and look at the Rio Grande Gorge, the widest part of it there, that's a 1:1 scale model of the Hadley Rille on the Apollo 15 landing site. We set up a field trip for them there, where they worked along the edge of the cliff, and a mile away on the other side with their telephoto camera, they took a panorama. Then as they worked their way down to farther stops, they did it again. That gave us a stereobase to study the rocks on the far side, and they did it on the Moon. It's really neat. You can pretend you're there on the Moon, because you can see this stuff in stereo and you can see the different layers and work out a better history than you would have had otherwise. Of course, the locals in Taos love it. "Our canyon was cut with water. Yours was cut with lava, though." And they're both just lava flows stacked up. That was one of the last of the field trips before they went, but it was a perfect 1:1 analog to what they were going to do.

The mission itself, since I was sitting in the other room, I don't know what kind of headaches appeared during the thing. They always do. They couldn't get to a couple of the points. In the overall, I don't think it mattered. Their prime reason for landing there, they were close to the mountainside of the ancient rocks on which we thought there ought to be some rocks big enough of the lunar crust sitting there that got blasted out of the Imbrium impact crater and standing there in those mountains. Where they landed at the kink in the rille would be a good place, and secondly, we could see this canyon and figure out maybe a little better why it's there.

So Dave Scott picked up this thing and started describing it. "It has big white rectangular crystals that are flashing at me." He knew what it was. He knew anorthosites, but he was unwilling to say it when millions of people were listening, for the fear that he could be wrong. It's too bad. But that's the rock that the newsmen nicknamed "Genesis Rock" because it would tell us about the origin. It's the first time we had a rock—about the size of my fist, actually a little smaller. First time we had enough of a rock where we could destroy a bunch, do all the lab stuff necessary, and find out that, yes, the Moon was born at the same time as the Earth was, and meteorites, which confirmed the astronomers' assumption that the planets are all formed in one big episode, instead of flying in and joining the team, however else you might want to do it.

That rock, Genesis Rock, gave us that sample material to prove that, up to that time an assumption. Now we know it. Actually, when you look at a thin section of that rock, if it's got "Genesis", it's got "Exodus" and "Deuteronomy" and probably even some "Revelations" in it, but it was a battered up hunk of rock.

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Joseph P. Allen, Astronaut, Apollo 15 CapCom
Interviewed January 28, 2003

Two very different agendas
[The rock] was physically very large. Most of the samples were small. They were just stones that came back, which got loaded aboard and brought back for detailed study. But the Genesis Rock was a conglomerate. I’m not sure what it was made up of, but a lot of basic information came out of that rock. The fact that it was different and physically large and had what seemed to be quite unusual characteristics was exciting to us. There are some photographs in the NASA archives that show Dave Scott and me looking at the rock in the Lunar Curatorial Facility afterwards, all wearing our white clean-room caps.

I hope the history shows that there are two very different agendas that somehow found themselves on Apollo. One was to take an American to the Moon and return him safely. That was one agenda. And the other agenda, unwritten and uncommitted to, but kind of adopted increasingly as the missions unfolded, was a scientific agenda. “As long as we’re there, let’s get as much scientific information as we can.”

If you’re a flight controller and your highest priority is only to get somebody there and back, you just want him to step down onto the surface and then come back, because this is a very risky place, and the more time you spend in a risky place, the more chance there is for a catastrophe to happen, in front of everybody.

If you’re a scientist, the more time you can spend and the more activities you can do, the higher the likelihood will be that you will learn something of fundamental importance, and you realize that these two agendas are mutually perpendicular, or maybe they’re opposed to each other.

The Apollo that resulted was a combination and a compromise of those two totally different agendas. Now, was the proper balance achieved? No one knows the answer. A balance was achieved, and each agenda was satisfied to a degree. Neither perfectly. To this day, the scientists would like to have spent more time on each of the journeys out, and they also would like to have flown Apollo 18, 19, and 20. And we had hardware to do it and people to do it. But every time you flew to the Moon you took a huge risk.

After Apollo 11, there were very strong forces that argued, “Don’t go back to the Moon. We have done it, and we’re the best in the world, and let’s not run a risk of spoiling that.”

But others said, first of all, “Wasn’t that fun, and can’t we learn a lot more?” Ultimately, those arguments prevailed, and people did go back and consequently we learned considerably more about the Moon.

One could assert that an appropriate balance was achieved. Nobody was injured. So we played a risky game, but we got away with it, and we learned an enormous amount more about our solar system than we had known before. We didn’t learn everything, but we learned a vast amount more about our solar system.

We raised the bar an enormous amount
Gosh, Apollo 15, per se, well, it was a landmark mission in that we raised the bar an enormous amount on what one could glean scientifically from the Moon. Apollo 15 gave the world a significantly increased scientific return, which was repeated and actually improved upon with Apollo 16 and Apollo 17. In simplistic terms, I would suspect that virtually everything we know about the Moon comes from the discoveries of Apollo 15, 16, and 17. Some initial things came from Apollo 11, very important, very basic. But the complex set of detail about the Moon comes from the last three missions.

There are some great monuments on planet Earth. One is the pyramids. We’re not sure what they are monuments to, but they represent the collective effort of, clearly, tens of thousands of people. Now, it was probably the physical effort of most of them, but some mental effort of a few. One doesn’t know.

In my mind, the Apollo Program in its entirety is a monument of the same magnitude and beyond, and it represents the collective efforts of hundreds of thousands of people. These efforts are the aggregate of virtually every bit of human skill and knowledge in one way or another, all the way from knowledge of mathematics that had to do with the trajectory, to the knowledge of sewing that had to do with the putting together of the spacesuits. These bits and pieces of knowledge, processes, techniques, technologies, are across the entire spectrum of the human intellect, and they were all [combined to accomplish Apollo]. I think that is just extraordinary. I’m now reflecting upon a truly heroic effort on the part of a lot of people, including even the generosity of the American taxpayer. Virtually everybody in this nation celebrated that effort as a victory. To my mind, it was a victory of the human organization, dedication, and the human spirit.

As great an accomplishment Apollo was, it was nonetheless quite different. There were victories of exploration from earlier times, and there are names associated with them—Columbus, Magellan. And these are obviously brave, perhaps even foolhardy daredevils who attempted and did something. But, when it came to Mercury, Gemini, and Apollo, they are no longer an individual persons named, because the accomplishments were an aggregate of human effort. To me, that makes the achievement even more remarkable.

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Michael A. Reynolds, Space Scientist, Lunar and Earth Sciences Division
Interviewed March 2, 2005

That’s what we were looking for
We were all excited as always, because that’s what we were looking for. These guys were trained to look for the “Genesis Rock” and, of course, when they came back, everybody wanted to look at that rock.

Then, of course, we had a cadre, I imagine about eight or ten geologists, that worked for NASA. But these were—how do I want to say this? A chemist is a chemist; a geologist is a geologist. But geologists are two types. There’s the type that go out and pick up rocks and then there’s the kind that spend their time in the laboratories. The guys that were at the Manned Spacecraft Center were rock geologists. These guys went out and picked up rocks. They were hired because that’s the kind of stuff they were doing when NASA started.

The guy that was in charge of that, you’d pick up a rock and throw it at him. I picked up a rock one day and I threw it at him, and I said, “What’s that?”

He looked at it, and he said, “That’s a meteorite. It looks like this one.”

I said, “How the hell do you know that?”

He said, “Because clowns like you keep asking me.” [Laughter]

And it was, it was a meteorite. It was Keyes meteorite, and by the way, that’s what they did a lot of studying on early in the program, was with meteorites. If a meteorite fell, you can bet that the astronauts were going to be there the next day, because they wanted to get them out there to see if they could find the meteorite, because the meteorite looks a little different than a regular rock, because it doesn’t have the wear and tear of the air, water on it. It still has some really distinct features.

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Leon T. Silver, Manager, Geologist, Lunar Surface Geology Experiment Team
Interviewed May 5, 2002

Now, what do you do with a rille?
Apollo 15’s mission included landing a special kind of a lunar feature called a rille. In this case it was the Hadley Rille. Now, what do you do with a rille? Think about that. The rille is a winding depression, linear, serpentine in shape, with walls that gave you windows into the underlying rocks, which is always one of the most difficult things we had. The reason those windows were better than craters themselves, which also gave you samples of underlying rock, is because the walls were ordered, whereas everything on the rim of a crater was thrown up by an explosive impact, which was, if anything, the height of disorder.

There was none of the disordering phenomenon of an explosion involved, we thought, and it’s probably still true. So getting to go to the Hadley’s Rille required finding an analog. Well, felicitous circumstances. We probably had the best analog in the world in northern New Mexico. It’s in the Taos area, and it’s called the Gorge of the Rio Grande, and about five or six million years ago, there was a tremendous set of basalt flow outpourings into a depression, through which the river has cut a gorge, just about the same width and the same depth as Hadley Rille. I remember suggesting that to Bill Muehlberger, who had done a lot of important work in the area, and he said, “Jeez, why didn’t I think about that?” That was one for me. Well, finding that was extraordinarily important and felicitous, but that isn’t what was felicitous.

For the first time in an extended way, in the exercise along the rim, we’re using a special vehicle, which was called the “Grover,” and the Grover was the U.S. Geological Survey’s preparation for the Lunar Rover, which had yet to be driven on the lunar surface. It was going to go up with them. The Grover worked like a charm, and it was electrical. It ran well. It didn’t begin to have the capacity, because it was operating in one G instead of in one-sixth G. It didn’t begin to have the capacity. But it was stupendous.

We had these two crews working along this straight gorge, about 800 feet deep, about 1,200 or 1,400 feet across, and the river down below. They didn’t have that river on the Moon, but we had everything else. We had the individual lava flows. We had interflow sediments. The stuff wasn’t covered with the debris that three and a half billion years had produced on the rille, you understand, but, nevertheless, you could see all kinds of things, and you could develop the logic. We are seeing a stratigraphy, and we could determine what was older and what was younger.

We didn’t know what we’d see when we got to the Moon, but we hoped we could do some of that. We didn’t do as much of that as we’d liked, but from my point of view, the crew could see it. They knew what they might be able to see. They knew what to look for. I didn’t have to coach them on what you’re going to do there at the rille, and we didn’t know for sure, because we knew that the Moon was covered with debris layers which had accumulated for billions and billions of years.

I got kind of tired
It was on missions like this that the crew understood enough; I didn’t have to point out what was relevant every time, and it was a damn good thing. One night we all convened in my room for a debriefing on the day’s work. So we started to debrief, and we went through it and we went through it, and it had been a long day. We operated at 7,000 feet—that’s the elevation of the Taos Plateau. These guys were in the Grover.

In some cases, I had to run along behind them. I got kind of tired. And I remember that this one night I started talking, debriefing them, and then I stopped. You know how you’d talk and you were waiting to hear the next part of the sentence? They were all waiting. I’d fallen asleep. [Laughter] Oh, they forgave me. It was the kind of group we had and the kind of working relationship. It worked out.

They revised the experiment and did it better
They brought a lot of good science. But that’s because [the crew] got into the science. There’s no way we could have told them what to do. There were so many things they did that were special. In a little foothill to the Hadley-Apennine, there’s a crater. There’s a crater called St. George’s Crater, and we were going to go to the St. George’s Crater because the rim of craters is where you get coarse debris, bigger samples that you can do certain things with that you can’t do with the fine dust or what we called the regolith on the Moon.

There was an experiment for a group of people who were interested in what the solar wind and cosmic rays were doing to the surface of materials on the unshielded Moon. On Earth we’re shielded by atmosphere, by magnetic fields, and other things. So what is the nature of this stuff? We described a potential experiment for them. We got two rocks that were shielded on two sides, collect, see if you can get a photo down below, see if we could get some of the walls of the rocks that are partially shielding them.

They did better than that. They found a rock and rolled it over and brought up the shielded side. They sampled the unshielded side. They sampled the shielded side. They sampled the soil underneath it. You understand, they revised the experiment and did it better.

Man, did that make me feel good. I hadn’t taught them that. They were smart enough to do it. And that went through all the experiments.

First-time experiences in an alien environment
This is anecdotal, but it’s in the records somewhere. One of the things was to get as high up on the flank of Hadley Delta as they could get. Remember, this is the first mission in the lunar world with a Lunar Rover. Nobody knew exactly how well that vehicle would perform. We’d asked them to pick up lots of big angular fragment samples. On the way, all of a sudden, there was an uncalled-for stop. Dave worried, muttered something about “I’m fixing the seatbelt.” Bald-face lie. They’d seen a big rock, thereafter known as the “seatbelt rock,” which they stopped to pick up because it was interfering with the time lines in their mission. In the end, that would redound on the accomplishments they’d hope for. Well, they got the piece of rock.

But then they started up the slopes, and they wanted to get to a place where they could get debris which had been thrown up on the slope from the great impact event represented by the Imbrium Impact. Okay, kept going up, but it got steeper and steeper. Finally, off in the distance, they saw a rock, and they got up to the rock. They couldn’t quite get up to the rock; it was too steep. And they got out of the Rover, and Dave got out first, and then Jim started to get out, and as soon as Jim started to take his weight off the vehicle, it began to slide down the hill. First-time experiences in an alien environment.

Jim had to stand there for a while until he felt that he could get the darn thing set and not get away. They went over to the rock, and the rock was on a gentle slope. Jim looked at that thing, and he said, “Gee, that looks kind of green.”

Now, prior to that time, color was never used in describing, because the Moon was in shades of gray from white to black. And Dave pushed his [sun visor up]. “Yeah, it does. We’d better get some of that.” So he got it. That’s the first time, and green was just the first color that subsequently became very important in the science objectives. But they responded, and they collected it, and it was beautiful. It turned out that this was made up of zillions—you know what a zillion is; ten to the x.—zillion beads of green glass. And nobody told them to look for green glass, beads, or anything like that. They did a beautiful job of sampling, and that was the highest sample they collected on the Apennine.

Gee, look what I’ve got
Down below there was this spot where they were wandering out, a little further down, and they were walking along and Dave reached out with this device we had created where he could grab onto a rock and bring it up, and he brought it up. And Dave said, “Gee, look what I’ve got.”

And Jim said, “That’s it.” What they had found was a rock made up mostly of the mineral called feldspar, and geologists have a special name for that, and it’s called anorthosite. Now, if you look at the Moon, either in high-quality photography or when you’ve got a full Moon, you’ll see darker parts and lighter parts. Well, they’ve already identified that the darker parts, which are called mare, are made up of lunar basaltic lavas. Apollo 15 was one of the beginnings of our beginning to understand the uplands. We were not keen to do many trips to the uplands, but in Apollo 11, people sorting through the finer fragments began to see little bits and pieces of what looked like rocks which were called anorthosite, and here it was a piece that was that big [Silver gestures]. It wasn’t a little teeny piece; it was a big hand specimen.

And because we’d learned from 11 and had built it into the experiments—I had taken them to a place in the San Gabriel Mountains behind Pasadena where we have anorthosite, and they’d looked at it, and we had discussed the fact that the anorthosite might have been the most primitive or primordial rocks on the lunar surface. When they picked this up, they said, “That’s it,” and they described it a little bit, and in the back room we knew that they had picked up a piece of what looked like anorthosite.

The press heard that. In the debriefing between EVAs, they said, “What was that rock they found when one of them said, ‘That’s it’?”

And whoever was talking from the back room said, “It sounded like they found a piece of anorthosite.”

“Anorthosite. What’s that?”

“Well, it might well be very old stuff.”

So the press created a name. They called it “Genesis Rock.” That didn’t come out of the science room at all; it was the press created it. But Genesis Rock, regardless of the press creation, turned out to be one of the most primitive samples, possibly the most primitive sample, we found on the Moon. Well, that’s kind of interesting, because Apollo 16 then went on to visit a place where we would have had acres and acres of that stuff.

It was an exciting piece, and again, they knew what an anorthosite looked like. And completely aside from its ultimate significance, it might not have given any answer that was very special to the work I was doing and other people were doing. It took, and it was operative, and that’s what they were thinking about. So we couldn’t help but feel good about it.

So Apollo 15 sort of, if I can use the phrase, it was apotheosis of all the things we’d been planning to do, and we did so many other outstanding things in subsequent missions. But it was the coming together of developing the technical capabilities, preparing men to be explorers, as well as many, many other things, and then, I’m going to say, felicitous things. How did we know that they’d find Genesis Rock? How did they know they’d find that green stuff? How did we know that that boulder would be sitting there in such a position that they could do all these things? Well, that’s because the human intention, well educated, well prepared, can squeeze things out, you understand? They can extract them.

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Gary E. Lofgren, Geologist, Geologic Science Training Coordinator, Apollo 15
Interviewed April 22, 2009

That was a big deal
Apollo 15 was the first mission that was going to go to a much more complex site. The geology we had was at the edge of this big Imbrium Basin, which was a 1,500-kilometer-diameter basin. We were going to be landing on the basaltic volcanic rocks that dominated the center of the crater, but we were right next to the mountains at the rim. This was the first chance we were going to have to collect primitive lunar crust. So far, we hadn’t really done that. We knew it existed. This was the first time we dared land close to the mountains, that the mission controllers said, “Okay, we’ve got really good with this landing thing now. I think we can land near a mountain.” That was a big deal, because we came over Hadley Mountain, which was pretty high. I forget exactly how high it was above the mare, but about 11,000 feet, and then plopped down right on the other side of it. Then there was a big little less than one-and-a-half-kilometer-wide valley bounding the other side. It was a rille. We think they’re a volcanic feature, but it’s still a little open to question. They’re probably basically a volcanic feature related to the lava flows, but it’s sometimes hard to tell for sure.

They had to land in this area in between the mountains and the rille. They had to come over that mountain and plop it right down, which they were able to do. They landed very close to their target place. Let’s see. We had two fundamental objectives, which were looking at the volcanic rocks and collecting the pristine primitive lunar crust, the first part of the lunar crust that formed.

I know what this is
In the training, we went to two kinds of sites. We went to volcanic sites like Hawaii and a couple of others, but we also went to sites where they would see the kinds of rocks we expected to find as part of that primitive crust. People think of granite as a rock that crystallizes deep in the Earth. Well, it’s not the technical granite that the geologist thinks of, which has compositional implications. This is a rock that is all particularly one kind of feldspar. It’s an anorthosite, which is rich in a calcium aluminum feldspar called plagioclase or anorthite. We went to places where they could look at those kinds of rocks. There was a place in southern California in San Gabriel Mountains. There was a place in northern Minnesota. There’s a big complex of anorthosites there. In the San Juan Mountains in Colorado we looked. They weren’t anorthosites, but they were granitic plutonic type rocks. We wanted them just to have seen some of those kinds of rocks, because we were hoping that they would get a chance to sample them.

Sure enough, actually they did. People have probably heard of the Genesis Rock. That’s the one they found that really was part of that primitive crust. What was rewarding was that Dave recognized what it was immediately when he saw it. He picked it up and looked at it and said, “Well, I can see the twinning in this feldspar. I know what this is. This is what we came for.” Some comment like that in the transcript. So everybody was all excited about that. They did an excellent job of sampling.

The things we tried to accomplish in the training were to teach them to be good observers of the geologic landscape. These are guys that are trained test pilots, they’re trained to know what’s going on around them, to observe what’s going on around them. But looking at the rocks and looking at the landscape is a little different thing than they were used to looking at. So we had to teach them how to do that in some kind of systematic way, how to describe it, and also to help them develop a vocabulary that the geologists had in common with them.

Our technique was not to try and change their vocabulary too very much or to give them the full technical vocabulary that a geoscientist would use, but to learn the way they described things. They picked up a bunch of geologic terms over the 18 months they were training, but we made no great effort to insist that they learn all the technical terms for what they were describing. Just let them do it and let them get used to doing it and let them get good at it. Then we would learn the words that they would use and what they mean.

That was a prime thing to teach them, to develop a vocabulary for describing what they were seeing, and to develop that common vocabulary with the scientists. The technique we used I think was really quite good. It did evolve and get better over time.

We would have the crew going out and collecting rocks
We would have them set up with radios. They would be talking to a couple of geologists who could not see what they were seeing. They were sitting in the “science back room” someplace back near the base of where we started. We also had the CapCom out there, the guy who would be the real-time CapCom for the mission, in this case Joe Allen. He was on all these trips, and he served that function on all of these trips, so he was learning the vocabulary as well. He was learning how they were going to do things and work in the field, because he was the CapCom for all three of the EVAs. He had to know what kinds of things they were supposed to be doing.

He would be talking to the crew, and there’d be a couple of geologists sitting there with Joe. They had the same maps the crew had. They’d listen to the crew’s descriptions, and then they would make notes on what the crew saw at a given point and a given station. We’d have predetermined stations. They would try to find these stations. They got pretty good at navigating their way around and finding things. They would go and then they would describe it carefully and collect samples. Talk back and forth their geologic observations.

This would be a four or five-hour exercise. Then we would stop and have a little lunch. Then the geologists who were sitting in that back room would get together with the guys, the crew who were walking out there. We would always have one or two geologists walking with the crew in the field. Lee Silver often did that. I often did that. We would see in real time what they were missing and what they were doing right and doing wrong. But the first thing we would do is walk out with the guys in the back room and let the guys in the back room see what the crew had been describing and then tell the crew how well they did it. How good a picture they got of what they were trying to describe. So that conversation would go on, then Lee would pipe in and tell them the things that he could see that they missed.

So that was the general technique that was used. We did that over and over again. It was like 18 field trips. Every one of these 18 trips was at least 1 or 2 traverses, some maybe even 3 or 4. So it was well over 30. So they had lots of time to do this. That accomplished very well this ability to describe and to communicate with the geologists. These were the geologists who were going to be working with them in the real mission as well. It allowed the crew to get to know the guys back and forth and develop some rapport with the guys that they knew they were going to be talking to and would be sitting in the back room in the real situation.

Just a general feeling for how you do geology
While we couldn’t match the geology from the Moon obviously, being on Earth, we would focus the objectives for the field training in the same mode as we had objectives for what we were going to try to accomplish at the Apollo 15 landing site. While we were doing all this, they were learning what the real objectives were going to be when they went to the Moon, because we would always relate what they were doing here to what they’d be doing on the Moon. While it wasn’t exactly the same, they understood why we were going to these kinds of sites, and what we were trying to accomplish by having exercises at these sites.

That gave them just a general feeling for how you do geology and how you can relate. How doing a geologic exercise, while it’s not exactly what you’re going to do on the Moon, builds that fundamental knowledge base that allows you to do what you need to do when you get there.

A very useful kind of device
Apollo 15 for the first time carried a whole new sampling device that was conceived of after we went to the Moon and we realized that this would be a good sampling tool. I have to give credit to the engineers who allowed us to develop this sampling device and get it on a mission in pretty short timeframe. It was what we referred to as a rake. It actually turned out very well-designed. It was like a scoop, but with tines. It wasn’t a solid scoop. It had these fairly thick wires, eighth-of-an-inch-diameter wires about a centimeter apart, so that when they dragged this through the soft lunar soil, you’d pick it up, all the soil would fall out, but the rocks bigger than a centimeter would remain in there. Those are the ones that we wanted to collect more of, because we were looking for variety, and we thought the most variety might be in these smaller samples that could have been bounced in from farther away.

That turned out to be a very useful kind of device for sampling. They would practice that, although most terrestrial geology is not suitable for using that tool. The soil gets very hard and crusty, and on the Moon it’s not hard and crusty. So you have to have a special place to practice with the rake. We had special procedures for collecting rocks. We would take a particular set of photographs. For collecting soil we would have a particular set of photographs.

They didn’t even have to think about it
In all of their traverses, they would use all of these techniques all the time to collect samples, so that the sampling became just really second nature. They knew how to sample without having to stop and think, “Oh, what do I do now?” It became so ingrained, so automatic that they knew they were going to collect a sample, “This is what I do.” They didn’t even have to think about it.

They carried a little device that they would set on the ground by their sample. Then they would take a picture looking down Sun with the Sun to their back. Then they would do these cross Sun photos. So we had the set routine. They’d go through the set routine, and that became very much second nature. They had to learn this and get this ingrained so they could think about the geology and not have to think about so much what they were doing. We knew that would be important as well. That worked out very well, too.

Doing those techniques over and over again, I think the guys just got very confident in what they were doing. They felt like they could go up there and do a good job. They knew they could do that. There wasn’t any trepidation about saying something. They weren’t shy about describing what they were describing because they had the confidence that they could do that.

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Farouk El-Baz , Geologist, Supervisor of Lunar Science Planning and Operations; Principal investigator for Visual Observations and Photography
Interviewed November 2, 2009

Who was your advisor?
Joe Allen is the one that was fascinated by my beginning. He would ask, “When did you come out of Egypt? Why did you do such and such? What did you study in Egypt? What was that like?”

For Apollo 15, we were having a briefing, but during the day they were off for something. It was a holiday, but we never took holidays, but it was a holiday. We decided okay, let’s take an afternoon and go cook some hamburgers and have a cookout and some beer, and we’ll come back. We did. So he and I were sitting next to the fire that we built to cook the hamburgers. The other guys were standing with some beers out in the distance. He said, “Farouk, who was your advisor?”

I said, “What do you mean?”

He said, “Your thesis advisor.”

I said, “Oh, you wouldn’t know him.”

He said, “Why? He’s got to be one of these guys,” Kuiper or big names in astronomy.
I said, “No, no, you wouldn’t know him.”

He said, “What do you mean, you wouldn’t know him? What do you mean? Where did you get your PhD?”

I said, “In something called the Missouri School of Mines and Metallurgy.”

He said, “School of Mines and Metallurgy?” He assumed that I had it in some astronomical thing that relates to the Moon, because I’m the Moon man as far as he’s concerned. He said, “What was your adviser’s name?”

I said, “His name was Chris Amstutz. You wouldn’t know him.”

He said, “What was your thesis topic on, the PhD?”

I said, “It was about the lead and zinc deposits in southeast Missouri.”

He said, “You’re kidding.”

I said, “Honest to God.”

He said, “Lead and zinc deposits in southeast Missouri? That was your PhD?”

I said, “Yes.”

He said, “Hey guys! Come hear this. You’re putting your lives in the hands of a guy who’s an expert on lead and zinc!”

He was right. What the hell is a guy who’s an expert on lead and zinc doing teaching astronauts about the Moon? He’s the one that would later say that, “The only man on Earth that I’ve ever met that knows the Moon like the palm of his hand is Farouk El-Baz.” Joe Allen himself, said this in one of the debriefings.

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