Michael Carr

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ORAL HISTORIES
Interviewed by
Ronald Doel
Interview date
Location
U. S. Geological Survey, Menlo Park, California
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Interview of Michael Carr by Ronald Doel on 1987 June 22,
Niels Bohr Library & Archives, American Institute of Physics,
College Park, MD USA,
www.aip.org/history-programs/niels-bohr-library/oral-histories/5088

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Abstract

Early schooling and education in England; training in geology at London University; Ph.D. studies at Yale University in late 1950s; work on problems in lunar and Martian geology in the 1960s. Detailed discussion of his research at Yale with Carl Turekian, involvement with high-pressure geological research at University of Western Ontario, and participation in 1960s Air Force-sponsored Luster Sounding rocket program to determine micrometeorite flux rates.

Transcript

Doel:

I know that you were born on May 26, 1935, in Leeds, England, and your parents were Harry and Monica Carr, but I don't know what your parents did or much about your early background.

Carr:

Well, my father was a draftsman. We came from a fairly, not very well-to-do family, very sort of working class family in Leeds, which is an industrial city in northern England. And I went to a really very good high school there, Roundhay High School, and high school in Britain, of course, you start when you're 11 years old. And that's where I got my basic science training, because in the English system then—I don't know whether it still is—you have to specialize very early, and I specialized in science, oh, by the time I was 15, I was specializing in science. And you take an exam called the ordinary levels.

They still do that. And after that you specialize. I specialized in biology, chemistry, and physics at that time. And it turns out, the class that I was in in high school was incredibly successful. The small group of people that I ended up with went through what they call sixth form there. Almost all of them ended up with Ph.Ds. Last summer I was back visiting a namesake of mine, Noel Carr, who was also in this class. He's a very successful molecular biologist. It was a very stimulating environment. Then I went on to University College, got a scholarship to go to University College, London.

Doel:

Before we turn to your career at the university, do you recall anything in particular which led you to science? Did you read a lot about science when you were young?

Carr:

I'm really not sure. I think it was mostly that I was very much career-directed. Having come from a fairly poor family, there was a lot of pressure to get into some technical field so that you would not have any problem getting a job. I mean, there were practical considerations. And I really think that was the main thing, to get some technical background, for security reasons.

Doel:

Did you talk about that much with your parents?

Carr:

Yes. My mother—not particularly my father, but my mother was very concerned that we all be self-sufficient, and she was probably a much stronger influence.

Doel:

Do you have brothers and sisters?

Carr:

Yes. Most of them are over here in Canada. I have a brother in Vancouver, sells lumber products; another brother in Toronto who is actually involved in a teachers' union there. He was involved in high school teaching and ended up as president of the teachers' union in Toronto. And a sister in Montreal who's a therapist. She has a PhD in psychiatry and is a therapist. Then I have a brother back in England who was in the Royal Air Force for many years, is now working for a mail order company there. So we're spread all over.

Doel:

You were living in Leeds during the entire time you were in high school?

Carr:

Right. I went to high school just about at the end of the war. Left high school in 1953. It was a very austere time. The post-war period in England was very grim, very difficult. We all had ration cards, and there was very little available food. I remember when I went down to the university, I had to take my ration card. That was in 1953. As late as 1953, I had to take my ration card down to London to give to the people I was staying with there.

Doel:

That's interesting. How do you feel the post-war experience affected you?

Carr:

I don't know that it affected my education that much, but it affected me in the sense that I came over here. I think that had a major effect, because the opportunities in England were so limited at that time. Well, that was a little later, when I finished my undergraduate work in England at the University of London. There was still a sort of carry-over from the very difficult post-war years, and there was a lot of talk then about "brain drain" and so on. England was losing a lot of its better and more qualified people, not just to the United States, but to Australia. At that time, there was a lot of emigration to Australia and Canada.

Doel:

When did you begin thinking about leaving for another country?

Carr:

Oh, not until my last years as an undergraduate.

Doel:

Do you recall any classes in high school, science classes, that were particularly memorable?

Carr:

I had a very good physics teacher. It's sort of strange. When I think back, I think back to that physics teacher, and this was probably when I was only 13 or 14. But see, I have had essentially no training in physics, I mean no university training in physics. I had not had a single university class in physics. But the training earlier on was really quite good. I mean, I'm not a physicist, but nevertheless I do a lot of modelling and so forth that requires physics, and yet I haven't even had an undergraduate course in physics. I also had a really inspirational biology teacher.

It's funny. I mentioned that I'd been back to see my friend from that era last summer who's in molecular biology, and he thought that this Mr. Morant, his name was, could take a lot of credit for the fact that this small class did so well. We were all so inspired by, we were so enthusiastic, you know, inspired, yes. He was very enthusiastic. He was also very personable. We all really got along well with him.

Doel:

How many were you in the class?

Carr:

Well, there were about twelve, twelve of us in this sixth form class.

Doel:

Do you recall times when you met after school to discuss scientific problems or to work in general? Were you socializing quite a bit as well?

Carr:

Yeah, I was a very avid Boy Scout, and again, this Noel Carr, this friend was also in that same Scout troop, and a couple of other people, and that was our socializing, and yes, there was a lot. It was a very high level of socializing, actually. You know, I look back and think, compared with what my kids do in socializing—

Doel:

You mentioned you'd also taken the exam in chemistry. Were there also chemists, teachers of chemistry that you remember in particular?

Carr:

Oh yes. It's funny, I remember—I almost can still visualize my chemistry notes, which always surprises me. See, I had both—I'm talking about high school—both organic chemistry and inorganic chemistry, and thermodynamics. Can you believe this in high school?

Doel:

That's remarkable.

Carr:

And I can particularly visualize my organic chemistry notes, because the chemistry teacher was such a stickler for precision and neatness that he always looked at your notes to make sure that they were all laid out and organized in a form that he thought was appropriate. Well, so, I was always very conscious of the layout of the notes on the pages, and that in fact is a very good memory device, because that's still embedded in my mind, here forty years later or whatever.

Doel:

Do you still use that technique?

Carr:

No, I'm a totally messy note taker. I can't take notes for anything.

Doel:

Why don't we talk a little bit about your university education? Was there one university in particular that you'd set your sights on, or were you thinking of a number of them, when you were finishing school?

Carr:

Well, you know, in England, everybody wants to go to Oxford and Cambridge. But the structure of education in England, certainly at that time, made it very difficult to get to Oxford and Cambridge, because someone who just comes from an ordinary high school—

Doel:

class background?

Carr:

The class background. It's the class system in England that's just so pervasive in everything. Most of the so-called public schools, which are private schools in England, they have a lot of leverage on the colleges at Oxford and Cambridge, and it's much easier if you go to a known high school, what they call public schools—to get into Oxford and Cambridge. It's very difficult for someone from our high school to get into Oxford or Cambridge. I applied but I didn't get a scholarship to Oxford or Cambridge. I ended up getting one to London, which I think was my next choice.

Doel:

And you got a fellowship to go there.

Carr:

Right. From our high school, that was almost the only way to go. You had to get a scholarship or you didn't go, because nobody could afford to send their children to university.

Doel:

Did you find it sufficient to live on?

Carr:

Well, I worked during vacations. Every summer I worked in the canning factories. That was a very popular way of earning money when you were going through school, because you could work very long hours and get a lot of money in a very short time, and so I think every summer as an undergraduate I worked canning strawberries and peas and what have you. And I worked for the postoffice during Christmas vacations. So with that combination, you know, it was adequate.

Doel:

What had you intended to study when you first came to London?

Carr:

Oh, I knew. In England you have to know before.

Doel:

Did you know your discipline specifically?

Carr:

Geology, right.

Doel:

How much experience had you had directly in geology?

Carr:

Oh, none. You know, you look back. When you're young you can do these crazy things, that end up controlling your whole life. But my interest in geology had come largely again through being in the Scouts, and camping all over northern England, and I sort of got interested in the geology, and that's what led me into geology.

Doel:

Did you begin reading field books on geology?

Carr:

If I knew we were going to go to a certain place, sure, I'd read something up about it. Not only geology, but general historical background too. Well, that's what led me into it.

Doel:

Were you also collecting rocks?

Carr:

No. No, I never did that.

Doel:

Do you remember any courses that you had at the university in particular?

Carr:

I had all the standard geology. I did mostly geology. My other principal subject was chemistry, and geography. I think those were the only three subjects I had in college. The system is different. I had the full array of geology subjects, you know, stratigraphy, paleontology, petrography, petrology, the whole—everything, all of geology. And then chemistry, I mostly had physical chemistry, a course in physical chemistry. I had a lot of analytical work, did a lot of lab work in chemistry. That was a prerequisite, as I recall. And inorganic and thermodynamics.

Doel:

I'm curious about the lab work that you were doing then. Did you feel that the experiments that you were doing were cookbook type or did you feel that you were actually doing...

Carr:

—no, totally cookbook. It was totally useless. It was looked upon as an obligation that had to be discharged, you know, that I had to get over with.

Doel:

Did you get a chance later to actually observe research while you were there?

Carr:

Well, you see, I was a geologist. Research in geology, particularly in those days, was field work, and I did a lot of field work. We used to have a spring field camp. Every year, I did field work in northern Wales and south Wales and Dorset, about various places around England. But also I spent a summer in northern Norway, with four people who are still very prominent geologists, Roy Rutland is director of the Australia Geological Survey, was there with me. And Keith Ackerman, the mineralogist, and Robin Nicholson, who is a full professor at University of Manchester. We were up there for a very full summer, mapping metamorphic rocks and the caledonides.

Doel:

Do you recall what summer that was?

Carr:

Let me see, it probably was '55, because I finished in '56. It must have been '55.

Doel:

I'm curious about the field camps that you mentioned a moment ago. What was it like to do work in the field camps? What did you feel you'd gotten out of it?

Carr:

Well, field work is the essence of geology, it really is. You know, you don't get any sense of the complexity of geology until you go out and try and do it. And that era—things have changed now in geology, but in that era, if you specialized in geology, you really had to spend a certain amount of time in the field. They were wonderful experiences. A group of us would go and we'd stay generally in some very pleasant place in the country in England, not necessarily an inn but some sort of boarding house. It would be fun. We'd be all out there together. We were generally given a mix of things to work on. We would have conducted field trips, but we also would have mapping projects that we had to do. It was a good experience.

Doel:

That's interesting. How many were you on these trips?

Carr:

Oh, many. Eight, something like that.

Doel:

Eight fellow students and how many instructors?

Carr:

Maybe a couple of instructors.

Doel:

Would you have discussions after hours of geologic ideas, concepts?

Carr:

I'm sure we did. You know, mostly what you do on a field trip is just talk. When you're out there in the field. I'm sure it carries over.

Doel:

Do you remember any instructors, professors at the university, in particular?

Carr:

Well, the fellow who—the guy we all called Prof. He was head of the department. A fellow called Hollingworth. And he was a very well known economic geologist. He'd spent a lot of time in Chile, copper deposits in Chile, and so on. And he was very influential, I think. He was very personable, in a gruff sort of way. Terrible lecturer, but everybody came away from that college with a very good feeling about him. And it turns out that University College, London, has produced other planetary geologists. It's rather strange, because of course there was no planetary geology in those days. But John Guest, who was probably really the only planetary geologist in England, was from the University of London. It was a good experience.

Doel:

How much interaction did you have with Hollingworth? Was it only in the class room that you met him, talked with him?

Carr:

No, he used to invite the department out to his place every now and again. But there really wasn't a high level of interaction. Most interaction was with the graduate students, who were around, and this Roy Rutland whom I mentioned was a graduate student there when I was an undergraduate, and again Keith Ackerman was too. That's where there was most interaction. They were sort of looked upon as staff, and there was a lot of interaction.

Doel:

I see. Do you recall any conversations with him in particular?

Carr:

No.

Doel:

OK. Let's turn to another area. I'm curious if you had any strong interest in philosophy or philosophical questions during your student days? Do you feel that that played any major role in the development of your scientific career?

Carr:

I don't think so. I mean, I went through all the usual kinds of querying that one does when one's young, but I don't think so.

Doel:

When did you begin to determine the precise field within geology that you wanted to work in? How did you come to that decision, when you think back on it?

Carr:

Well, it was some time during the undergraduate work. It may have been set by going to northern Norway for a summer, because that's a particular kind of geology, and that's the kind of geology that I thought I wanted to do. I changed it later, but it was metamorphic petrology—I'm a structural geologist—that I was primarily interested in at that time, and it was what I was primarily interested in when I started here in this country at Yale. That's what I thought I was going to do.

Doel:

OK. What was it like being at University College, London, in the 1950s?

Carr:

Well, it was actually a pretty good life, because we lived in the center of London. I lived for the whole time in this sort of a Georgian Square, Cartwright Gardens, it was called, within walking distance of everything in London, so I had access particularly to theater. Theater then was very inexpensive, and of course it's the best theater in the world. And we would go to the theater just like you go to the movies. Just on the spur of the moment, one would say, to a bunch of guys, "Hey, let's go down and see so and so," and we just went down and saw it. Looking back on that, it was just an incredibly fortunate time to be around, because one couldn't do that any more.

Doel:

Right. It certainly doesn't happen in the US.

Carr:

It doesn't happen in the US. And it's—you can still do a little of that in London now, but the prices of course are out of sight, and it was very pleasant. London is a very civilized town. You can be in the center of a city and yet you're isolated from it all. You can live in tree-filled squares and so on, and have access to all the things that a big city can offer. And a lot more than any American city can offer.

Doel:

You miss that, I suppose.

Carr:

Yes. That part of it.

Doel:

Do you remember attending colloquia during your undergraduate days, scientific colloquia?

Carr:

I can't say I do. Well, the Geological Society of London had their meetings once a month or, I forget the frequency, and we would go down to those Geological Society meetings. They're a lot different from the Geological Society meetings here, because they were held in this old old building off Picadilly. Geologists from all over England would come. All the big names were there, and so one got to hear them talking, and there was a lot of interchange from the audience. It wasn't a passive audience. It wasn't someone giving a talk and everyone sitting there quietly listening. There was a lot of controversy, particularly in some areas. At that time the Scottish Highlands were really just starting to be mapped, and there's a lot of controversy there. There would be heated discussions by people like Kennedy from Leeds, and Sutton and Watson, and Reid from Imperial College—they'd get in these big arguments. And that was exciting. That was fun. That was fun seeing the people whose papers you read, and also fun seeing the interchange, which tends to be pretty bland in the US meetings. Maybe it's pretty bland there now. But then it was a small community and everybody knew everybody and there were a lot of personality clashes.

Doel:

That's very interesting. Were you making contributions, questions?

Carr:

No. Hiding in the background.

Doel:

The Picadilly Building, was this the one that had existed since the 19th century?

Carr:

Oh yes, Burlington House. It used to be a private home. I don't know the history, but yes, they've been meeting there for 150 years, I think.

Doel:

I recall seeing a floor plan of that building.

Carr:

Big marble stair cases.

Doel:

The meeting rooms where people are facing each other.

Carr:

That's right, it's like the Houses of Parliament, exactly. Yes.

Doel:

Do you recall any one debate in that, that you attended? In addition to the Scottish Highlands controversy?

Carr:

Well, I really can't, because this whole business of the Highlands was just an ongoing thing. The origin of granite was a big issue at that time. There were debates about that, and migmatization (?) and so on. They all fused. They all fused together.

Doel:

Was there any other of the students at University College that you remember particularly well?

Carr:

Well, I've mentioned one already, Robin Nicholson. He and I were fairly close. It was a very small department.

Doel:

How many were there?

Carr:

In our class, I would say about 8??. About 5 graduate students in geology. And Robin is really the only one I can remember now.

Doel:

How did the geology department compare to other science departments there?

Carr:

I think it was quite good. The geology department at University College was a good department. University College is a good school. You've to understand, the University of London is a very complicated organization. The colleges are independent in the different parts of London. You have Kings College, University College, Imperial College. They're all parts of the University of London. They all have their independent faculty, but the exams are set by the university. University College was—maybe, after Oxford and Cambridge—one of the best science schools in England, if not the best after Oxford and Cambridge.

Doel:

Right. Did you have much interaction with the astronomy department?

Carr:

None at all. Didn't even know they existed.

Doel:

Or physics department, any other?

Carr:

No.

Doel:

OK. You mentioned a little while ago that it would have been your last two years of school that you began thinking about leaving Britain to come to another country.

Carr:

Yes. It was in my last year, actually. Well, at that time, I was just curious about the United States, and there was an opportunity. I'd probably seen a brochure or poster. I'd talked to someone about the possibility of getting a scholarship to go to the United States. I remember I applied to three places, Yale, Princeton and Berkeley. Probably the reason I applied to those was that those were the places that had scholarships. I didn't know what the best schools were. And I remember being rather surprised, I ended up getting a scholarship. Yale was the first reply I got. I accepted. It was a joint English Speaking Union at Yale Fellowship.

Doel:

Who administered that scholarship?

Carr:

The geology department at Yale, essentially. But the English Speaking Union I guess provided half the funds.

Doel:

That's interesting. How had you known about Yale and Princeton and Berkeley when you made the applications? Did you know the faculty members, any one in particular?

Carr:

I really didn't. I knew virtually nothing. Really. I mean, I'd heard of Yale. I'd heard of these three places. But, you know, not much more.

Doel:

Right. You left then for the United States in 1956.

Carr:

Right.

Doel:

What were your experiences when you first came here?

Carr:

Well, it was kind of fun coming over on a ship. I came over on the QUEEN ELIZABETH, and landed in New York. It was kind of terrifying to come from a civilized, polite city like London and to be dumped on the dock in New York, with piles of luggage and raucous-type cab drivers and so on, not knowing anybody. But it worked out OK. In fact, what happened was that, the English Speaking Union at Yale arranged to have, not a sponsor but a contact in New Haven. When I got to New Haven, there was a family that had volunteered to help visiting students and so on. Each of us was assigned to different families. That helped. Just to transition in. So when I arrived in New Haven, I did at least have a name I could call.

Doel:

It certainly helps.

Carr:

Yes. But as far as, you know, the schooling, in England of course when you're through, you go into graduate work, you're through all course work. At Yale I had to go through two years of course work, which I didn't find too burdensome, but I also had to pass language exams. Well, that was one thing I did very quickly. I learned before I left England that I had to pass an exam in German. I'd taken no German. So I went to the German department and got a lot of notes and on the ship coming over I went over all these notes, and within a week of arriving in New Haven, I took a German exam and passed it, much to the annoyance of a lot of people there who had two years of German and failed!

I was glad that I had to take the course work, because I learned an awful lot, and also of course got to know some of the people at Yale, particularly John Rogers, who was just a very impressive person, very knowledgeable, a very open and approachable man. He taught structural geology, and I ended up deciding that I would do a thesis under John Rogers, and I started out doing it. It was a mapping metamorphics again in New England, in Connecticut. I spent two summers doing that, and it caused me to re-think what I was doing with my career, because I found it very unpleasant, largely because of the climate. Going out in 95 degree weather and 100 percent humidity and walking over those hills in Connecticut just wore me out. I just found I couldn't handle that kind of discomfort all day long. I didn't want to do it the rest of my life!

Doel:

It was your introduction to the continental climate.

Carr:

Right. I started looking around, thinking about redirecting my career, at that time. A new guy arrived on the scene in New Haven, Karl Turekian, and incredibly powerful personality, enthusiastic, brilliant, and just a powerhouse. He persuaded me, and I was ready to be persuaded, to do a thesis in geochemistry. And that's what I did. Turekian arriving on the scene was really a kind of a start and a change in the department at Yale. It was a new kind of a geology, and with emphasis on experimental work and quantitative approach, rather than the traditional field geology—a revolution in the department. I was Carl's first student.

Doel:

How did your department members, the senior faculty, react to this change?

Carr:

—oh, there was a lot of resistance, tremendous, particularly—well, there really was. It was a difficult time for the department.

Doel:

There were quite a few senior faculty members coming to retirement at that time, weren't there?

Carr:

Yes, that's right. Richard Flint was a very well known quaternary geologist, very conservative, ultra conservative, very precise. He just simply couldn't handle Turekian's—well, his style, which was really emotional and uncontrolled and what he would consider ungentlemanly kind of behavior, and there was a tremendous clash of personalities there. Flint retired shortly after I left, just within a year of my leaving. Yes, it was a difficult time.

Doel:

Which other geologists on the faculty do you remember particularly?

Carr:

Well, you know, two really that I've mentioned, John Rogers and Karl Turekian, were the ones that had the most influence. Really those are the two. I could name all the others, but they didn't really have much effect.

Doel:

You didn't have as much interaction with them.

Carr:

No, Flint and Winchell and Jensen and Bateman, I didn't really have much interaction with them. But I had a lot of interaction with John Rogers and Karl Turekian.

Doel:

Do you remember any discussions with Karl Turekian about the style of geochemistry that he wanted you to pursue?

Carr:

Oh, very much so. He was unmarried at that time, and so mixed a lot with the graduate students. Actually a lot of graduate students found it a little overbearing, because he was such a powerful personality. You know, a lot of us felt we couldn't escape him. He was everywhere. You went down for a coffee, you went down for a beer, and there he was. He was always pushing his philosophy of geology, this quantitative approach, experimental approach, see, and it happened every day.

Doel:

That's remarkable. What had his own background been?

Carr:

Well, he's Armenian and never let you forget it. He had gone to a little Bible college, Wheaton College in Illinois, as an undergraduate, and then gone on to Columbia. Columbia at that time had a very strong geochemistry group, the strongest in the country, I would say, at that time. Maurice Ewing was there, the oceanographer, and it was just before plate tectonics really broke. All the people who ultimately became involved in this revolution, were in effect at Columbia, mapping the ocean floor and doing a lot of work on the ocean floor samples and so forth. Turekian was in the middle of it all. Turekian, Wally Broker.

Doel:

Right, and at the Lamont Observatory.

Carr:

Right, it was at the Lamont. It was at Lamont, yes, there were a lot at Lamont.

Doel:

Is that where the main interactions took place?

Carr:

Yes. And so I went down there several times with him, for meetings or just to talk with people and so on.

Doel:

Do you remember what kinds of problems they were talking about?

Carr:

Oh, there was a lot of talk about ocean sediments as possible records of climate change, but there was also a lot of talk about isotopics, particularly argon, trying to understand the evolution of earth's atmosphere, how the earth's atmosphere formed by looking at the xenon and argon isotopes and so forth. Karl was particularly interested in strontium, strontium rubidium, and what that told you about the evolution of the oceans and generally the chemical evolution of the earth, because there was a lot of this information embedded in the strontium rubidium isotopes. They were pretty broad problems, a lot different from field geologic problems. Quite different problems.

Doel:

Do you recall any discussions about plate tectonics?

Carr:

We had a guest lecturer there, Carey, William, University of Tasmania, and for one year, and he was incredibly stimulating. And he—it wasn't really plate tectonics, but continental drift. He gave a course in continental drift. This was before any plate tectonics.

Doel:

That's remarkable.

Carr:

Everyone thought he was a madman. He had a whole sort of vocabulary of his own—spheno chasms, for example—but he recognized that you simply couldn't explain global geology with everything just staying in place. But he got all the details wrong.

Doel:

Details of the mechanisms?

Carr:

Of the mechanisms. An expanding earth, I think, was his mechanism. But also a lot of details about how the continents have shifted around. But nevertheless, he was convinced that they had shifted. And it was a stimulating class, as opposed to, all the other people on the faculty were very conservative.

Doel:

His course was being offered?

Carr:

Yes. I was less conservative at that time, because the resistance to continental drift was mostly in this country. In England, there was much less resistance to continental drift, largely because a lot of the English geologists—because there's so little geology in England—had been all over the world, and particularly in the Commonwealth countries of South Africa, Australia and so on. They had been influenced by Wegener, and Holmes, who wrote the standard textbook in England, and firmly believed in continental drift. And so I was brought up on the prospect that there could be continental drift. And Holmes—I still have his book on my shelf there—really was very prescient.

Doel:

Do you remember talking with any of the Yale faculty about continental drift?

Carr:

Oh, when Carey was there, we talked about it all the time.

Doel:

Did you talk with Carey about this?

Carr:

Oh yes. Carey was another dynamic personality.

Doel:

What kind of a man was he?

Carr:

He was—well, he was a showman. And he had developed this incredible memory, and so he would play these memory tricks, party tricks. For example, he would shuffle up a pack of cards, 52, and then run through them, and then hand them to someone and just read them off in sequence. He had an incredible memory. He was a real showman in class, very powerful personality.

Doel:

Were he and Turekian particularly close?

Carr:

I don't think they were. I'm not even sure they overlapped. Yes, they must have overlapped. I don't recall. I simply don't recall.

Doel:

How did you come particularly to the PhD work that you did on cobalt? With Turekian?

Carr:

Well, it was at the suggestion of Karl. It was particularly suited to the instrumentation we had at that time, which was pretty primitive. He'd just gotten a capability to do neutron activation analysis, a limited capability, and he had an emission spectrograph, a big huge spectrometer. Those were the two techniques that I used in doing the study. There was virtually nothing known about what cobalt is and what controls its distribution and so forth. So it was a fairly routine thesis, I think, looking back on it.

Doel:

How had Yale gotten a hold of the instrumentation, the emission spectrograph?

Carr:

Well, I don't really know. I'm trying to think back. I think it was an NSF grant. For Karl. And he was looking mostly at strontium, and I suspect it had something to do with strontium, because he was looking at a lot of carbonates. I'm sure that's how it came.

Doel:

Was there any support coming in directly from the Atomic Energy Commission as well?

Carr:

No.

Doel:

Did Turekian have a strong influence on the style of research, the way that you did the research for your dissertation? How active a force was he?

Carr:

Oh, he was very active. He was involved in everything. In fact, he was so involved, and was so powerful a personality, I found I couldn't be around him for any more than a few hours a day. When I was under pressure to get my thesis finished, I ended up working through the night, and I'd leave at 8 o'clock in the morning to minimize my overlap with him. It was just, just—the personality was just too strong. Everybody had that problem with him. He's done a lot—I don't know if you know him at all?

Doel:

I haven't met him.

Carr:

He's still just an incredibly strong personality. Wonderful person. You know, I feel really warm toward him, despite my difficulties.

Doel:

I can understand it. Do you recall other graduate students at that time, those that you worked with or had a number of conversations with?

Carr:

Well, I can't. It's difficult to pick out any single individuals. I mean, I remember close friends in the geology department. None of them have really done much. But there were other people who were there when I was there who have done quite well. Clark Birchfield's at Harvard now, I think, and Bill Berry's up at Berkeley, a well known paleontologist. It was a good class. But I'm having trouble, you know, thinking who was influential among them, from a point of view of career.

Doel:

You mentioned a very interesting observation a moment ago, on the difference between the British and the American reaction to continental drift. Were there other contrasts that you observed, coming from Britain to America? The style of the universities, or the way the research was being done?

Carr:

There's just a lot of differences, because we specialize in England so early. When I arrived at Yale, my level of technical education was really, I think, substantially ahead of most of the people in my class. After the course work was over, I'm not sure there was that much difference. But that was certainly true. Also, there's a difference in the level of cultural education. Really, that was a big, big difference. I noticed from my class. The people I knew when I lived in London, were very different from that of the people I knew when I lived at Yale, it was night and day.

I wouldn't consider myself in any way an intellectual in England, because there were a lot of high powered intellectual people here. I'm thinking just broadly intellectual, cultural. But at Yale, among the scientists, there was really quite a lack of what we'd call culture, you know, culturization, really quite different from England. I have no idea why. It's not to say that there weren't cultured people here. There were, but they were in the English department, the history department and so on. They weren't in the science departments, whereas in England, you get people who are very cultured in science departments. You know, there are not many, but still they are there.

Doel:

OK. Was there anything in your education at Yale that you felt was particularly lacking, once you were away from it and could think about it?

Carr:

Well, I'm very aware of my lack in certain areas, and I wouldn't blame it on Yale. I think it's just simply the whole combination of the training I had both in England and the US. I should have had more math and physics, there's no question, I should never have been allowed to go through undergraduate work without math and physics training. Really, I think that's a serious deficiency. You know, I manage, but I'm frustrated by it all the time. And it's pretty hard to train yourself, if you don't have sort of a thorough grounding. I mean, I get by, but it really is a serious lack. That's a major area, I think.

Doel:

Did you feel that you were exposed to the most up-to-date theories at Yale?

Carr:

Yes, I think so. Yale is a very good school, and while it was teaching traditional geology then, and may have been a little slow in making the transition to a more modern style of geology.

Doel:

We're returning after a brief pause. Do you recall attending scientific colloquia at Yale? Do you recall any visitors who made a strong impression on you?

Carr:

I confess I don't. There was a continual stream of visitors coming in giving talks, and it's pretty hard for me to pick out any one of them. I can't.

Doel:

OK. There are a few other things I'm curious about concerning your dissertation research. Who else was working on processes causing the dispersion and concentration of elements in the earth's crust?

Carr:

Well, at the time trace element geochemistry was a fairly important part of geochemistry. It isn't so as much now. And knowledge at that time was fairly primitive, as far as how these trace elements were dispersed through geologic materials.

Doel:

How much of that was instrumental limitations?

Carr:

Well, it may have been. The bible at that time was a book by Goldschmidt, and really, he did all the pioneering work in trace element geochemistry. I'm trying to think of other people who were involved. I'm having trouble thinking of them. You know, I've been out of this field a long time, about 25 years or something.

Doel:

I understand. Do you recall any discussions on connections between the chemical abundances question with the cosmic abundances questions being debated at the time?

Carr:

Yes, there were. A lot of this was really peripheral to what I was involved in, but certainly that theme was always present. How do you explain the differences between the rock abundances and the solar abundances? As I recall, in Goldschmidt's book, he goes into that a little. And of course, he defined a lot of the basic terms, such as siderophiles and chalchophile, which people use now. I think he recognized that elements that had an affinity to iron tend to get concentrated in the core, which is why you don't find them too much in the crust.

Doel:

Did you have any discussions on this or any other topic with people in the astronomy department at Yale?

Carr:

No.

Doel:

Wildt was there at the time, wasn't he?

Carr:

Oh yes. Yes, Wildt was there. I remember a party at Karl's. Karl lived in an apartment in one of the colleges, and Wildt was there. Strange, looking back. I remember what the topic of the discussion was. It was kind of a party, but we had a theme for our discussion, it was "uniformitarianism." I can't recall the details of all the discussion, but he was there. I don't recall who participated in that, but it ended up revolving around a lot of chemical questions. It all seems kind of silly now, looking back, because we were all trying to understand what uniformitarianism really meant, because of course, chemical and physical processes are universal, all right, but are geological processes universal?

That is, it's been a tenet of geology for a hundred years that what you see going on now is how to understand the past, and I guess Karl was challenging that, because he said, this has been a chemical evolution, and a thermal evolution, and so you can't necessarily just look at the earth as it is now, because conditions are different, and you can't just assume the same processes were going on, because the chemistry was different, the thermal conditions were different. And that was the base of the discussion. And I know Wildt was there.

Doel:

Do you recall your own position at the time? Did you agree with Torekian?

Carr:

Yes, I agreed with Karl. Uniformitarianism is a useful tool, but you can't just blindly apply it.

Doel:

Do you recall the opponents in the debate at that meeting?

Carr:

I really don't. I can't even recall who was there, other than myself, Karl and Wildt.

Doel:

And you didn't have contact with Wildt in other settings?

Carr:

No.

Doel:

OK. Let's turn then now to the 1960 period. You received your PhD in 1960 from Yale, and you were then at the University of Western Ontario. How did this come about?

Carr:

Well, kind of by a series of accidents. I had a student visa, which meant I had to leave the country for two years. There was no way out of that. I had to leave for two years. I had already met my wife. I wasn't married then but I had already met her, and I didn't want to go back to England. So I decided to go to Canada: I started looking for a job in Canada in geochemistry. Well, you know, at that time, a job in geochemistry came up every ten years. I simply couldn't find a job. It was frustrating, because I was offered several jobs in the United States, one of which was the California Survey. Anyway, I ended up in Canada. Robert Uffen, who was the chairman of the geophysics department, offered me this job to do shock wave work. Shock wave work!

Doel:

In Ontario?

Carr:

In Ontario, yes. And since that was all I had, I went and did it.

Doel:

How much did you know about shock wave mechanics?

Carr:

I didn't know a damned thing. I didn't know anything, and I kept talking to Uffen on the phone. I said, "Look, I know nothing about shock waves, nothing." "It's no problem," he said, "it's cookbook stuff. I have a specific project, I got money from the Defense Research Board of Canada to do this very specific thing. It's a specific paper." He gave me the paper to look up, and I went and looked at the paper. Anyway, I ended up going out there. It was a very difficult time for me, because as I said before, I have no training in math or physics.

Doel:

Mechanics is of course largely mathematical.

Carr:

That's right. And I found within three months of arriving in Canada that the technique that he had proposed was simply nonsense. It simply would not work with geologic materials.

Doel:

What was he attempting to do?

Carr:

Well, at that time, I guess, the Defense Research Board of Canada was building a lot of underground facilities. There was a lot of interest, also a lot of interest around here, in the shock wave properties of rock, what they call the shock hugoniot of rock materials. In effect, it's the change in volume with pressure, the equation of state, of rock materials. There's a lot of work done on it at SRI here. But very little was known about rock materials, and so Uffen had gotten a grant to do this. He had said it could be done with a particular technique that had been developed by someone at Imperial College, using an air hammer to generate the shock waves. The guy was using lead in Imperial College, malleable lead. You simply could not use this technique for shock waves in rock material. You just generated an elastic wave. You never got to the shock regime, which I found out. So I'm stuck with this grant from the Defense Research Board of Canada to do something on shock waves which I know nothing about. I was stuck on my own.

Doel:

It must have been terribly frustrating.

Carr:

It really was. Anyway, I looked at various techniques. First, we had to use explosives to generate the shock waves. I mean, that was obvious. And you had to have an extremely responsive detector to detect the shock waves. The shock wave decays so quickly in the rock that we had to have a technique that would measure the time of arrival of the shock wave within tenths or hundredths of a microsecond. I tried various things, and I ended up finding strain gauges that could do this. It was always very marginal, you know, right on the edge.

Doel:

Right in the noise.

Carr:

Right in the noise. It really was. And the noise turned out to be a major problem. I'll talk about that later. Anyway, I essentially played around with that for two years almost. I was doing other things up there. I was teaching and you know, giving seminars and things. But I essentially developed a technique for doing it, I thought. I wasn't sure it would really work. I wasn't sure it really was working. I mean, I had nothing to check. And really it took me two years to develop the technique. I didn't really have any results by the time I was through in Ontario. Just a lot of very difficult sort of testing and so on. It's hard to get very fast oscilloscopes and build a special room, a bunker room, and put sand bags and everything in. It's—it all took time.

Doel:

Yes. Do you recall the amount of support that you had for this project?

Carr:

It was very little, actually. We're talking in terms of, I would guess, two or three thousand a year. A very small amount of money. That was another problem. I had to not only find a way to do it, but I had to do it at very little cost. Actually, it was a very frustrating couple of years at Western Ontario. However, that's what got me into planetary science. At that time, there was great interest in shock deformation because of the potential of getting to the moon and the expectation that the moon was hit by meteorites all the time, so that much of what would be found there would have been affected by shock. That was, I forget when, probably early in 1962. I wrote a letter to Gene telling him what I was doing, looking forward to leaving for a permanent job.

Doel:

This is Gene Shoemaker, of course.

Carr:

And within two days he was on my doorstep. Amazing. I was so surprised.

Doel:

That's interesting. He came up to Western Ontario?

Carr:

Oh yes.

Doel:

You'd read his papers, of course.

Carr:

Yes, I forget which I'd read. I think I'd read something in GEO TIMES about the finding of coesite. I think that's what triggered it.

Doel:

Right.

Carr:

He and Ed Chao. I thought I might as well give it a shot.

Doel:

Had you also read his study of Meteor Crater?

Carr:

I hadn't, at that time. But I had another offer from someone else, Cohen at Mellon Institute in Pittsburgh. I must have written to him too, because he was involved in the coesite work too. And they offered me a job too. But yes, Gene came and gave a little talk at the department there. He had a lunar map, the first lunar map, geologic map.

Doel:

What was the reaction to his presentation?

Carr:

You know, he's so enthusiastic, it's pretty hard not to get turned on by Gene.

Doel:

Were your fellow geologists at Western Ontario following this line of research with interest?

Carr:

No, I don't think so. There was only one group that really was interested, and that was C. S. Beals's, who was head of Dominion Observatory at that time. He was writing papers on what he called astroblemes and he was finding all these craters in Canada. That was the breakthrough in finding these very large fossil craters. And as a result of that, some people became involved. I can't remember their names. There's a Brent Crater in Ontario that some of the people in the department had cored. They were looking at the cores, to see the structure. We didn't know at the time whether it really was an impact crater or what. They were looking at breccias and so on from under the Brent.

Doel:

Were you in touch with Beals at the time?

Carr:

No, not really, although I did meet him. I went to the Dominion Observatory. You know, at that time the Canadian geologic community was very small, and astronomical, very small. We would go to Ottawa for talks, quite a long way.

Doel:

What brought you to the Dominican Observatory?

Carr:

We went there because of the craters. As I say, it was an interest in the craters at that time.

Doel:

This was while you were at Western Ontario?

Carr:

Yes.

Doel:

Do you recall others you had conversations with when you were doing impact and studies of mechanics?

Carr:

Well, there were the people in the department. There was a John Sass there who did a lot of heat flow. He's now over here, or was over here: he's now moved down to Flagstaff, but he was here for ten or fifteen years. There's an Alan Jessup who was also in heat flow, and I see papers by him all the time, in Canada. And I had a good friend there, a guy called Yerich who's a mathematician. He's now at UBC. [University of British Columbia]. There wasn't a—as I say, at that time the Canadian community was small, and Western Ontario was small, very small.

Doel:

How did the geology department at Western Ontario compare to other departments in Canada?

Carr:

Well, now it's quite a big department. It was very small then, and I don't think too significant. Uffen, who was head of the geophysics department—I was in the geophysics department there—is quite well known. He ended up I think directing the National Research Council, and ended up I think going into politics. He was quite well known. But it was a backwater. I haven't been back there, but I understand it's quite a large university now. I felt cut off from the world.

Doel:

That's quite a change from Yale.

Carr:

Quite a change. I used to go down at 2 o'clock on Sunday and meet the train from New York and get the NEW YORK TIMES. It was my lifeline. It really was.

Doel:

In the morning?

Carr:

Two o'clock in the afternoon, Sunday afternoon. I used to go wait for the train.

Doel:

Let me change the topic somewhat. What kinds of instruments were you able to gain access to at Ontario? Were you able to develop your techniques for measuring shock waves by using existing equipment?

Carr:

Oh yes. I just had to get a very, principally fast oscilloscope. I mean, with the strain gauges, I tried out a whole lot of different ones. But that was no problem.

Doel:

Then it was 1962 that you joined the U.S. Geological Survey, and you'd already been married then for one year. Do you recall the offer that you had? Were there any conditions or terms to it? What were your expectations?

Carr:

Well, it seemed at the time a terribly large salary. It was $9600. I do remember that. I'd been getting $5000 at Western. It turned out we could barely live on it. California is a little different. I remember almost not joining the Survey. They were so sluggish, the system is so slow—then it was so slow, I'm sure it's ten times slower now, that they just couldn't respond fast enough. I had this other offer from the Mellon Institute. I wanted to join the Survey, but gee, it was getting tight. And the head of the staffing committee, George Gric, is now in this office over here, in Menlo Park.

Doel:

What happened? How was it resolved that you came to the Survey?

Carr:

Well, I think it was just push. I think Gene said, to this committee back there, "Get moving or we're going to lose him." So it got resolved.

Doel:

What had Shoemaker told you of the work you were expected to do?

Carr:

Well, he wanted me to continue doing the shock wave work. He had all kinds of plans for how it would interface with other work going on in the Branch. There was Ed Chao, who was working on terrestrial impact structures. He wanted some way of calibrating shock structures that he'd found. There was another guy called Carl Roach in Denver (Chao's in Washington). Carl Roach was doing thermoluminesence work. And again, he wanted to do some experimental work to see under what conditions one induced the luminescence. He talked about my setting up this lab here, and my interfacing with his other people, getting samples, doing all that kind of stuff.

I was rather skeptical, because I knew the difficulties I had in setting things up at Western Ontario, getting the technique to work or even knowing that it was working, and to measure the loss of this—It turned out, I now know, that the way I did it could not have worked. But there wasn't enough known then. The problem was this. I used a rod of aluminum to attenuate the shock waves, so that I could expose the rock to different shock levels. There was an explosive and then a rod of aluminum and then a rod of rock. I stuck the strain gauge on the aluminum, and strain gauges on the rock, to measure the shock-wave velocity in each.

Well, to solve this problem, you have to have a single wave passing through the interface. You had to have a single shock wave in the aluminum inducing a single shock wave in the rock. I now know that because of the complexity of the rock, that rarely happens. It breaks up into a bunch of waves, and then the solution is no longer valid. But I didn't know that then. Anyway, that was the deal. I was going to set up the lab here, and I was also going to train some other people, possibly, see what I could do for these other people in the branch.

Doel:

How much freedom did you have in conducting your work?

Carr:

I was left entirely to myself. I was given a budget and that was that.

Doel:

Do you recall how much that was?

Carr:

Well, it was about three or four thousand dollars. We also had other expense money, to buy equipment and such. That's my recollection.

Doel:

Do you recall what you read on the problem of lunar crater formation? Did you come in contact with others at the time?

Carr:

Well, yes, as soon as I came here, I came in contact with all kinds of people, because there was a lot going on. There was Danny Milton here, who had done a lot of work at Meteor Crater. He was ultimately to go around and see a lot of craters around the world. There was Henry Moore. He was doing work down at Ames, where they were looking experimentally into the effects of impacts. And then Gene, of course, was doing his Meteor Crater work. Yes, there was a lot going on. So I was pretty well plugged in when I came here as to what was going on in cratering.

Doel:

Do you recall reading the works of Ralph Baldwin?

Carr:

Yes. Yes, although I didn't read it with the same sort of avidity that Don Wilhelms and Dick Pilu and some of the others did. Yes, Ralph's is a real pioneering work.

Doel:

Did you have disagreements with him?

Carr:

With Baldwin? I don't know that I had any. Cratering is not my main area.

Doel:

I understand.

Carr:

No, with Baldwin—everything Baldwin writes seems to me to make eminent common sense. He's one of the most underestimated, under valued pioneers in the whole thing. There's hardly a new idea that he didn't somehow see. He is incredible.

Doel:

How did the experience of being here at the USGS office in Menlo Park compare to your earlier employment at Western Ontario and the work that you did at Yale? What was the general atmosphere?

Carr:

Well, it's hard to answer. Just the physical setup here made everybody much closer, in a sense. They had this big pen out here where we were all sharing offices and so on, so there was a lot of interaction going on. Also, everybody was doing several things. I started out doing this shock wave work, but also I got immediately involved with the lunar mapping program.

Carr:

Also within a year—became involved in another big project, which we called Cosmic Dust. I forget when that started. But it was about a year after I came here.

Doel:

Tell me more about that.

Carr:

Well, it was something that I did for ten years. This took a big chunk of my career, Cosmic Dust.

Doel:

How were you led it?

Carr:

Oh, that was Gene. Gene pretty well asked me if I would do it. At the time, I was beginning to realize the shock wave work was not going to work. I was looking for some other direction, and he knew my chemical background. There's a lot of chemistry involved in this. The idea was that a lot of material is dumped into the upper atmosphere, other places too, that is of cosmic origin. Now, we didn't know at that time quantitatively how much there was. In fact, there was some false information. There had been some satellites that had microphones on board, that had been measuring the number of impacts. They were giving, it turned out, anomalously high numbers, because of thermal cycling. There was noise in the system, and the thermal noise was way more than the signal. They were giving factors of a hundred or so higher flux rates than ultimately turned out to be.

Doel:

These were the results coming back from the early 1960s.

Carr:

Yes, in '61, '62, that era. There was also a fellow at the University of New Mexico, a guy called Crozier, who had put out—he was collecting magnetic spherules, putting dishes out all over the place, collecting these things. Again, it turned out that most of those were not cosmic: that was just industrial dust. But there was some interest in this field at this time. There was also interest at NASA, because impacts were an important consideration for any design of satellites and vehicles. It was recognized that potentially one could sample and collect material this way. There were a number of experiments which were being designed, particularly one down at Ames here which was called Luster, a sounding rocket experiment, to sample material in the upper atmosphere. I'm getting a little hazy about dates now.

Doel:

It was in 1967 that you published "Micrometeorite Flux Determined," by Luster.

Carr:

Yes, OK. It must have been the end of '63—when did Kennedy die, '63?

Doel:

Yes.

Carr:

When Kennedy died, I was at a conference in New York on cosmic dust. So by that time, by November of '63, I had started working on this project.

Doel:

Was that at the Goddard Center?

Carr:

No, it was at Columbia. I think that's where it was. I got into that, got involved in that. It turned out that this scientific element of that project was a relatively small part of it. We ended up being funded by the Air Force to look at bomb debris in the upper atmosphere, a classified project. I spent a lot of my time in the mid-1960s working on that. It involved a capturing of this debris in the upper atmosphere. I set up an electromicroscope lab, and electromicro probe program, general chemistry lab, and X-ray lab with a group of about six people working on that. This lasted through the mid to late 1960s.

Doel:

And this was entirely funded by the Air Force?

Carr:

Almost entirely. We got a little money from NASA for the dust collection, for the extraterrestrial work. As I say, I was involved in the Luster program. That involved, just like any other mission, a lot of preparatory work before the thing was actually launched. We were given a kind of pan that would be mounted on the spacecraft, and we were able to put inside these pans whatever we wanted. Then these things would open up and close again.

Doel:

And the rocket would be recovered.

Carr:

Right.

Doel:

How did you design the instrument for Luster?

Carr:

Well, all I had to do was design what went in these pans. I went back to Washington to talk with a group of people back there, in the machine lab attached to a little chemistry group in Washington, and talked with a lot of people back there. That's the way it was built and tested. We had to go to Goddard and run shake tests and things like that.

Doel:

What was the technique involved for measuring the dust?

Carr:

Well, it was very primitive, really. We had a lot of electromicroscope mesh and individual mounts that were set on slides and then mounted in a tray. The electromicroscope mounts had various films on them to trap the particles. It was really very simple stuff.

Doel:

Then you examined these films directly.

Carr:

Right. And you can imagine the scale we were looking at. I mean, with an electromiscroscope, to examine any significant area just takes forever. And we never found anything that we felt was really a cosmic dust particle. We had controls and we couldn't detect any difference between the controls and the exposed slides. That was the topic of that paper.

Doel:

And that helped to put an upper limit on this material.

Carr:

Oh yes, we tried to put an upper limit on that. Later it turned out that there were errors in these microphone techniques and our results were actually right on. It was a disappointing result, but nevertheless it was a correct one.

Doel:

How much of your results were you able to publish?

Carr:

Well, I would say, out of all that work that we did in that era, we published maybe 5 percent.

Doel:

How did you communicate the results to the Air Force? Do you remember any contact you had with the Air Force in particular?

Carr:

Well, I can't tell you. I don't think I can even tell you now.

Doel:

It's still classified?

Carr:

I assume so. Nobody's told me that I can talk about it. But you know, there was a particular branch of the Air Force. We had regular meetings. There were people all over the country that were working on this. It was kind of funny, for a while. Let's see, I wasn't a citizen when I first started out working on this.

Doel:

You became naturalized in 1965?

Carr:

That sounds about right, and it had to be three years since I'd been naturalized. I would go to these meetings. In fact, I would write reports, and as soon as they were classified I couldn't read them because I didn't have a Q clearance. I couldn't read my own work!

Doel:

That's remarkable.

Carr:

And I could not go into restricted meetings. I would go to these meetings and talk about things, then I'd have to leave for the rest of the meeting, when they were talking about anything that needed a Q clearance. I had a clearance, but I didn't have a Q clearance.

Doel:

Generally where were those meetings held?

Carr:

Oh, they were held all over, because there were several institutions that were involved in this.

Doel:

Were these government institutions or also universities?

Carr:

There wasn't a single university involved at all at that stage.

Doel:

How did you feel about participating in a military project?

Carr:

Oh, I had no problem at all. It was essentially intelligence-gathering, and it seems to me that the sensible thing to do is to try and learn who's doing what. I have no problem with that, particularly when you're collecting it in your back yard. The information is coming from something that you just go outside and pick up. I have no problems with that at all. You know, what the classification stemmed from, was what one could learn from doing that, and it was really quite remarkable.

Doel:

Of course there was considerable concern for actual travel in space, given the earlier high readings.

Carr:

Yes, that.

Doel:

When you look back on that period, how much time did you figure you were spending in actual research, and how much in administration?

Carr:

I'd guess I was spending 60 percent doing research. Very little of it got out. If you look at my publication record during that era, it's very slim. And you know, I was doing a lot of work. But I don't regret it, because I learned an awful lot. It was interesting.

Doel:

How large was the group, the community, that you were working with? How many scientists were involved in this work?

Carr:

You mean here?

Doel:

Generally on dust in the micrometeor range.

Carr:

Well, there was this Air Force project, and a lot of people were in that. As far as the scientific part, the Cosmic Dust, it was I would guess a community of about 20 that were interested in that problem.

Doel:

Can you tell me roughly how many people were involved in the Air Force project?

Carr:

I'm not even sure I know, but we'd go to meetings and there would be 20, 30 people at the meetings. But who knows who they were representing and so on?

Doel:

You didn't know many of them very well?

Carr:

I got to know some of them quite well. Yes. There were institutions involved that I never went to, so I don't know how many people were involved there.

Doel:

You were also involved in the lunar mapping program at that time. Was that also inspired by Shoemaker?

Carr:

Pretty well. I think everybody in the branch was involved in the lunar mapping. We all had our little specialties, but lunar mapping we all did. And at the time, of course, we did it on the telescope. We'd go up to Lick Observatory several nights a month, all for our particular area of concern, and go at the appropriate times.

Doel:

Were you making sketches at the telescope?

Carr:

Yes, actually. We had maps, you know. We were trying to fill in, trying to discriminate between things on the telescope. As you know, you can see ten times more visually than you can on any of the photographs. Yet being there was very frustrating, because those glimpses just come every now and again, for a fraction of a second. Suddenly you see it and then it's just gone again and everything's swimming. It was kind of a difficult way of doing things.

Doel:

How long were your typical observing sessions?

Carr:

Two or three hours, I think.

Doel:

And you tried to get it at different illuminations, so you could see the areas under differing sun elevations?

Carr:

Yes. Generally you went up when it was a fairly low sun, where the terminator was pretty near the area you were looking at. Of course that comes up twice a month.

Doel:

Right. Did you recall having any conversations with the astronomers at Lick Observatory?

Carr:

Very little, actually. They weren't interested in the moon. They really weren't. They regarded us as kind of intruders, amateurs, which we were.

Doel:

Was there a night assistant working with you at the telescope?

Carr:

No.

Doel:

Were you left alone?

Carr:

We were left alone, wheeling that 60 foot tube.

Doel:

A very delicate instrument.

Carr:

Yes, the 36-inch. We did everything on the 36-inch refractor. It was a weird experience, actually. This seemingly ancient dome, old equipment, the big wheel. [equatorial]

Doel:

You felt as if you were back in another era?

Carr:

Yes, back a hundred years.

Doel:

Do you recall debates about lunar stratigraphy at that time?

Carr:

Oh yes. We had a lot of debates about lunar stratigraphy. We were always arguing about synchroneity, about time horizons and what constituted time horizons. Also how do you break up the stratigraphic column? Gene had devised a formal stratigraphic system. A number of us had some trouble working within that system, trying to revibe it and change it. We were always arguing, like any geologist always argues at map boundaries. You know, everything has to fit ultimately. There was one particular meeting we had at Flagstaff, fairly early on, when we were out at the museum.

Doel:

This is just after part of the Branch had moved down to Flagstaff?

Carr:

Yes. Well, we had a big wingding about the lunar stratigraphic column, particularly about whether to introduce a new system called the Procellarian I think. That was—Looking back, it's amazing how much excitement and emotions were stirred up over something so abstract!

Doel:

That's interesting. Do you recall who was at that meeting? Besides yourself?

Carr:

Well, Gene was there, and Eggleton and Don, Don Wilhelms, Jack McCauley, Harold Masursky, most of the old timers were there. Danny Milton.

Doel:

Do you recall what the particular debate was about?

Carr:

Yes, it was, as I remember, I think Gene had defined an Imbrium system which—now, I'm having trouble—it had to do with the—I shouldn't say because I can't recall now. I can't recall precisely. I'm embarrassed that I can't recall precisely what it was. But it had to do with the introduction of a new system called the Procellarian. Now I'm having trouble understanding why it was a new one. I think it had something to do—

Doel:

We can check on this, if you'd prefer.

Carr:

Yes. There was an Imbrium, beginning of the Imbrium, defined by the formation of the Imbrium basin. There appears to have been a gap before the filling of the basin. Some of us wanted a separate time system to correspond to the time when the basin was being filled, so the Imbrium system would start with the formation of the Imbrium basin and last then until the start of the filling of the basin. Then the filling of the basin would have taken place during the Procellarian. I think that's what it was about. Obviously it's not very important now in retrospect.

Doel:

Although it seemed to you so at the time.

Carr:

Yes, it created a lot of passion at the time.

Doel:

How were each of you assigned the particular quadrants that you worked on?

Carr:

I really have no idea. I don't remember. I just don't remember.

Doel:

How was the decision made to develop the separate branch down at Flagstaff? Do you recall discussions about the best way that work could proceed?

Carr:

I really don't, because I was involved in all this other stuff.

Doel:

The micrometeor dust work?

Carr:

Yes, I don't think I was heavily involved in the decision. But you see, the branch was becoming unmanageable, in that there were these two very separate elements that were going on within the branch. One was with direct Apollo support, and then all these other activities which had only peripherally anything to do with Apollo. It certainly made practical sense, but I don't remember the debates. Looking back, it seems to me that we split almost into two sub-branches within the branch before they were formally split. I can't recall the details.

Doel:

Roughly how much time were you spending on lunar problems in the early sixties?

Carr:

Oh, 25 percent maybe. Something like that. Really, my effort was doing the dust work. I mean, I had a large staff and lots of labs, and was learning new techniques, setting up complex instruments, developing instruments. We developed nondispersive detection of the microprobes, things like that. That was very time-consuming.

Doel:

Did you find that you were doing a different kind of science than you'd expected earlier to be doing? Did you find that you were spending for example far more time in instrument development than you had initially thought?

Carr:

Well, in a sense, yes, because I don't have a lot of experience in instrumentation. Yet here I was setting up a microprobe, which at that time was almost an experimental instrument. Also I had to learn to do electron microscopy, which is very delicate. The preparation of the samples is really a very delicate procedure. You know, I had no experience in it at all. And yes, it was new, but you're doing your thing, you know. I had not anticipated that I would be spending a major effort analyzing little dust particles. It's not what I expected to be doing.

Doel:

When did your involvement in the Air Force project come to an end?

Carr:

Oh, just about 1970, something like that.

Doel:

And when was it that you began becoming involved in the Mars exploration projects? That was earlier, in the 1960s, wasn't it?

Carr:

No, about '69, '68, '69. I'm trying to think. I think '69 or '70 was when I was appointed leader of the Viking Orbiter Imaging Team. It was one of those two years, I'm not sure which. Before that time, I'd become involved in the planning for Mariner '71, but not much before. But it was about the same time, '69, '70.

Doel:

How did you become interested in Mars research?

Carr:

Well, clearly that was going to be the next big thing in planetary science. I'd enjoyed what little experience I had then in some of the planning efforts for Mariner 9. I'd done some very cursory stuff with the Mariner 6 and 7 data. Not much, but we all got the data: we were all kind of curious. But it really wasn't until Mariner 9 results came in that I really got excited about Mars. Before that time, 1969, or in that era, it looked like Mars was another moon. It didn't look that exciting.

Doel:

Do you recall any of the planning meetings in particular? How actively involved were you in setting up the program?

Carr:

I don't think I was. I was very junior. On Mariner 9, I wasn't too actively involved, although I certainly was involved. I remember I was passionately concerned about certain elements. Initially there were two Mariner spacecraft, and one was to observe, was to do the geology: the other was to look at changes, try and detect changes. What they were going to do was to put the other one, the one to detect changes, into an orbit which passed over the same ground repeatedly. There were three sort of strips that the spacecraft would pass over repeatedly for the entire mission.

And I remember thinking that was a particularly stupid mission design. The chances of detecting changes and being able to tell what they are are small. The waste of just passing over the same track, you know, month after month after month, just didn't seem to make any sense. But anyway, after the first spacecraft fell in the drink, we had to merge those two missions, and come up with a mission plan that did both geology and the variable features. It was a very intense period. I can remember meetings at JPL, particularly with Carl Sagan and Bruce Murray, two very strong personalities, going at one another, on opposite sides of this issue. Ultimately, they got an actually good mission together.

Doel:

Were you able to communicate your opinion on the initial design of the Mariner mission?

Carr:

I don't think so. I was pretty junior, pretty meek in those days, not too confident, particularly with strong personalities like those two.

Doel:

Did you find that to be a characteristic of the program, or of the imaging team?

Carr:

Well, no. I'm not sure the question you're asking. We ended up actually having a major effect on the mission when the mission was actually in progress. Carl Sagan is not one who sits around and works on missions. But the nuts and bolts of the mission, getting the sequencing done, targeting, involved a lot of work. There were a few of us, and yes, we did it all. We worked things out, trying to figure out where things were. It was very difficult because we had no way of locating things very accurately. We would have to go down for planning meetings every few days, and do the next series of updates of the mission. We had a blackboard there, we had everything laid out, orbit number and the kinds of observations, then try to fit everything in. We always had to come up with a suitable target. We worked very hard on that mission. And for most of the specialized targets, there was some systematic work. Most of that targeting was done by the working troops, of which I was one.