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ORAL HISTORY TRANSCRIPT
GE R. CARRUTHERS INTERVIEWED BY GLEN SWANSON WASHINGTON, DC ­ 25 MARCH 1999

GEOR

S

WANSON

: Today is March 25, 1999. This oral history is with Dr. George Carruthers, at his The interview is being

office at the Naval Research Laboratory in Washington, DC.

conducted for the NASA Johnson Space Center Oral History Project, by Glen Swanson. Dr. Carruthers, I'd like to once again thank you for joining me this morning in this interview. I'd like to begin by again addressing your background, particularly what led to your interest in science, and, specifically, in the work you've done in astronomy and cosmology.

C

ARRUTHERS

: Well, my interest in space science and astronomy came about by reading

science fiction comic books when I was about nine years old, and then after that I became interested in astronomy because I came across some books on the subject. Of course, that was long before there was a space program, so people weren't really overly enthusiastic, including my relatives, about my interest in astronomy. They thought I should pursue something more practical, such as engineering, because my father was an engineer, but he also gave me an interest in technology as well. So once I moved to Chicago [Illinois]--I was actually living in a rural area near Cincinnati, Ohio, called Milford, Ohio--when the family moved to Chicago, then I had access to a much broader range of resources, like public libraries and so forth. And also I came into contact with the Adler Planetarium and spoke with some of the astronomers there. Just prior to that, the famous issues of Collier's magazine, featuring Dr. Wernher von Braun and others who were proposing space flight for the first time, human space flight, like space stations, and Fred [Lawrence] Whipple had proposed using space as a base for

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astronomy. But when I talked to the astronomers at the Adler Planetarium, they said, "Well, you know, that's fantasy. That's science fiction. Ground-based astronomy is really the thing that we do, and we think that there's no advantage in going out into space." But I was really interested in space from the engineering point of view as well, because of having read about it in Wernher von Braun's publications. So I went to the University of Illinois and obtained, basically, the equivalent of a dual background in aerospace engineering, with minors in physics and astronomy, so that I could cover sort of like both aspects of the subject. When I was in graduate school, I read about postdoctoral appointments at the Naval Research Laboratory [NRL], which I had read about quite a bit already, because they had developed the Viking rocket and the Vanguard rocket and several other space astronomyrelated projects. So I applied for a postdoc [postdoctoral research associateship] to come to Naval Research, and I've been here ever since.

S

WANSON

: You mentioned that your father was also an engineer. How much of an influence

were your parents in nurturing your interest in astronomy and your eventual career path?

C

ARRUTHERS

: Well, they weren't so much of an influence in the astronomy and space flight

part, but my father, being a civil engineer, instilled in me the importance of learning about math and science in general.

S

WANSON

:

Did you have any heroes at the time when you were growing up?

You

mentioned you enjoyed science fiction. Were there particular writers that you enjoyed reading more than others, and then also real-life individuals? You mentioned Dr. Wernher von Braun.

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C

ARRUTHERS

:

Well, actually, the only real motivator person that I'd actually had the

opportunity to contact directly was Dr. von Braun, because after reading his articles in Collier's and other places, I sent him a letter saying I was interested in space and all that sort of thing, and he actually sent me an autographed photograph, which I had totally unexpected. That was while he was still part of the Army at the Redstone Arsenal [Alabama], before the creation of NASA.

S

WANSON

: During your college career, obviously it was during the sixties, a lot of civil

unrest and so forth. Did you find, because of your race, any obstacles in your education career?

C

ARRUTHERS

: I don't think that I really had any overt obstacles in my college education. Of

course, African Americans were like 1 percent of the engineering students there, so we were relatively rare, but I never saw any instances of discrimination that prevented me from doing whatever I wanted to do there, on the part of either professors or other students.

S

WANSON

: You mentioned your coming to the Naval Research Laboratory. You received a

scholarship or you worked as a co-op student or an intern?

C

ARRUTHERS

: It was a postdoctoral appointment when I came to NRL, which was funded by

the National Science Foundation at the time, and that was my first real chance to have handson participation in space science, because NRL was one of the few organizations that was directly involved in the space program.

S

WANSON

: What were some of the early experiments work that you did relating to the space

program prior to Apollo?

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C

ARRUTHERS

:

Most of our work was done with sounding rockets in those days, and

sounding rockets have the advantage that you can build something on a relatively short time scale, a relatively small expense, and get results from it quickly. So one of the projects that I came to do as part of my postdoctoral appointment was what was then a hot topic, which was look for molecular hydrogen in interstellar space, which could be detected only by the use of ultraviolet spectroscopy, and therefore required rocket flights above the atmosphere.

S

WANSON

: On these sounding rockets, can you relate any interesting incidents with failures,

either during the launches themselves or recovery of the payloads?

C

ARRUTHERS

:

Well, actually, as was also true of the film The Right Stuff, where the

astronauts were shown examples of the rockets they were supposed to ride blowing up on a launch pad or early in flight, there were quite a few mishaps even in the sounding rockets, so either the rocket not getting to sufficiently high altitude, or the parachute not working, or the attitude-control system that needs to point the instrument at the target of interest not working properly. So usually it took two or three tries to get one fully successful result.

S

WANSON

: Leading up to the work on Apollo, can you basically describe how you came into

working on the camera that was used on Apollo 16?

C

ARRUTHERS

: Well, shortly after the first Apollo lunar landing in July 1969, NASA put out

an announcement of opportunity for scientific experiments on the follow-on Apollo missions, and I put in a proposal to use an instrument similar to our sounding rocket experiment on the Moon to look back at the Earth, specifically to study the Earth's upper atmosphere, which is difficult to study, even from low Earth orbit because of the fact that the hydrogen atmosphere

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in particular extends out a very large distance away from the Earth, and also we proposed to use the camera for astronomy as well, which would take advantage of a lower sky background on the Moon than would be available in low Earth orbit. At the time, there was also another proposal put in by Dr. Thornton Page, who at the time was on a sabbatical at Johnson Space Center [JSC] in Houston [Texas], to do a very similar kind of experiment, more focused on astronomy, and he proposed a number of alternative instruments, including one of the type that we had developed here at the Naval Research Laboratory. So NASA looked at these two competing proposals and suggested that we join forces, so we did that, and the program was then set up with Dr. Page and myself as co-principal investigators. I would be in charge of developing the instrument and he would be in charge of the further development of the observing program and the data analysis.

S

WANSON

: The program was pretty intense as far as time-wise when you received the go-

ahead approval with your proposal to the time of the actual instrument. Can you describe a little bit of those days working on the instrument and some of the highlights and problems and pleasures that you encountered during that project?

C

ARRUTHERS

: Yes. It was a very intense time scale, because the schedule was determined

by the launch schedule, and the time from start to finish was only two years, so we got approval in 1970 to go ahead with it, and the launch was in April of 1972. The advantage, though, was that money was no object in those days, unlike now, and there was plenty of funding so that we could have a much larger staff of people to work on a project than would have been typical of a sounding rocket. Why, we had Engineering Services Division here at the Naval Research Laboratory to support us and many other people in specialized roles to support it, so that, to some extent, compensated for the very compressed time scale, in

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contrast to missions nowadays which have been much longer from start to finish, but also funding is a lot harder to get these days.

S

WANSON

: When you were developing the camera itself, you met with the astronauts

frequently during the development of the camera?

C

ARRUTHERS

: Not very frequently, but we did have a lot of meetings down at Johnson Space

Center with the other engineers, mostly on engineering details and mission-planning details. We did talk to the astronauts on a few occasions and we also did some training sessions with the astronauts in the final stages down at the Cape [Canaveral, Florida] to show them how we operate the instrument, make sure that they knew what to do once it was deployed.

S

WANSON

: Can you describe a little bit about the deployment of the camera? You were

there at JSC at the time of deployment during the mission?

C

ARRUTHERS

: Yes, I was there actually before the Apollo [16] landed, and there was some

delay because of an engine problem that they had on the service module, which is the device that has to bring them back to the Earth, and we were almost afraid that they weren't going to land. But then at the last minute they decided to proceed with the landing, and we were very much relieved at that. I believe that the actual deployment of our instrument was almost a day after they landed, certainly not immediately after they landed. But I was there for that part of the mission operations, and we could--as is true, even now, the scientists did not have the chance to talk directly with the astronauts, but we were able to hear what the astronauts were saying and give some input to the mission controllers about what the astronauts should be doing.

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We could actually hear them talking about our instrument. Like, for example, John [W.] Young was using a sight on the side of the camera to point it at the Earth in order to set the reference for all of the other targets that we were going to be using, and he verified that he had sighted the Earth and it was in the center of his field of view.

S

WANSON

: Describe the camera, actually how it works. It's not a typical point-and-shoot

film camera.

C

ARRUTHERS

: It's really an electronic camera. It's a type of camera we call electrographic,

which uses film, but is also an electronic imaging device. We call it electrographic because the imaging device produces electrons, just like in a videocamera. But instead of being recorded by CCD [Charged Coupling Device] or other electronic imaging device, it actually hits the film and is recorded directly as darkening of the film, and it's more quantitative and also a lot more sensitive than direct photography. And unlike the electronic imaging devices, the film does have to be recovered and brought back in order to get the data.

S

WANSON

: Was that a little frustrating for you, knowing that, unlike some of the instruments

where they could actually monitor the data that they were gathering immediately, you had to pretty much wait until they came back before you knew if your instrument worked or not?

C

ARRUTHERS

: To some extent, but we knew that ahead of time, and that had always been

true in other flights, including sounding rocket flights, that we wouldn't know for sure what we got until we processed the film.

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S

WANSON

: Was this a considerable time after the mission completed before you could pretty

much bring closure to this point in your life, knowing that the results came through, the film was processed, and you could start analyzing the data?

C

ARRUTHERS

: Yes, it was sort of an apprehensive time, because it was like a couple of

weeks between the time that they returned and the time that the film was actually processed by the people at Johnson Space Center, so I wasn't there at the time and would not have been able to participate in it even if I was there. But once we found out that the images were good, we were certainly quite relieved.

S

WANSON

: What were some of the results? In laymen's terms for some of our readers of

these interviews, what were some of the results from the camera, the highlights, that you found?

C

ARRUTHERS

: Well, the most immediately obvious and spectacular results were really for

the Earth observations, because this was the first time that the Earth had been photographed from a distance in ultraviolet light, so that you could see the full extent of the hydrogen atmosphere, the polar auroris and what we call the tropical airglow belt. All of these were revealed in pictorial form for the first time, so that's something you don't have to wait for data analysis to show people. We also obtained UV [ultraviolet] images of stars, including the large Magellanic Cloud, the nearest nearby galaxy, but these were less immediately different from things that were done from sounding rockets and from low Earth orbit, at least in terms of the general public.

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S

WANSON

: Were any of the results used from the Apollo 16 instrument later dusted off and

compared to some of the subsequent missions where this instrument was flown? Is there a similar instrument aboard the Hubble [Space Telescope]?

C

ARRUTHERS

:

No, there's not on the Hubble, because the Hubble is a much more

specialized, high-powered telescope with a very narrrow field of view, whereas our cameras are really more survey instruments with wide fields of view, so you can actually map a large area of the sky, or take a picture of the whole Earth, or whatever, so it's really different kind of science than most of the other NASA missions have been, including our own missions in low Earth orbit, like on the Space Shuttle [STS-39] in 1991 and the ARGOS [Advanced Research and Global Observation Satellite] satellite, which we just launched this year.

S

WANSON

: You mentioned that this was also flown on a later Skylab mission. How did the

instrument differ on the Skylab flight, as opposed to that that was used during Apollo 16?

C

ARRUTHERS

: On the Skylab flight, the primary objective was to observe Comet Kohoutek,

which was prominent during the time of the mission, and since it was in the Skylab space station, all we really needed was the basic camera. We didn't need the stand, the tripod, and the pointing system that we had on the Apollo mission, where it was pretty much a standalone instrument. So the backup camera from the Apollo mission was used for Skylab, but not the whole tripod assembly.

S

WANSON

: Why wasn't this camera flown on subsequent Apollo missions? Why was it just

on Apollo 16?

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C

ARRUTHERS

: Well, actually, we would consider ourselves lucky to have had even one

opportunity because of the fact that the highest priority of the Apollo missions was on lunar science specifically, and many of the lunar scientists felt that something that's looking at the Earth or looking at the stars is lower priority then, in terms of the uniqueness of it, compared to lunar science. But we justified it because of the unique perspective of the Moon for doing astronomy, in comparison to low Earth orbit. But we did not have a second chance, that's true.

S

WANSON

: And going into the development of the camera for that mission, you knew that

ahead of time?

C

ARRUTHERS

: Yes.

S

WANSON

: Did that in any way influence the design of it, what you wanted to accomplish at

that point?

C

ARRUTHERS

: No, because even if we had a reflight, it would have been basically the same.

S

WANSON

: Going back with Apollo 16 and the instrument flown on Skylab, and then you

had the same or similar instrument flown on several Shuttle missions. How did those differ from the previous missions, particularly the Shuttle missions?

C

ARRUTHERS

:

The Shuttle mission, being in low Earth orbit, had somewhat different

objectives than the Apollo mission. Also, on the Shuttle flight, which was on STS-39 in the spring of 1991, we had two cameras mounted on a pointing system so that we could obtain pictures in two different colors of ultraviolet light at the same time. But aside from that, it

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was basically the same instrument technology as used on the Apollo and in the sounding rocket flights.

S

WANSON

: Did you use some of the data from the earlier missions in your science for the

Shuttle missions as well, and was that useful?

C

ARRUTHERS

: Yes, because it gave us a baseline of what to expect in terms of instrument

calibrations. We could look at some stars that were the same in the two missions, and use those to compare the sensitivities of the two instruments, what we call inflight calibration. And also the fact that we had done something similar gave us a better idea of what to expect in the later flights.

S

WANSON

: You mentioned that on the Shuttle flights, starting with the first one, STS-39, that Can you expand a little bit more on the

they no longer used film, but these CCDs.

differences between the film versus CCD, the advantages, the disadvantages?

C

ARRUTHERS

: Well, actually, the Shuttle flights did use film, just like the Apollo mission,

but what has changed recently was the long-duration, unmanned satellite mission called ARGOS, which stands for Advanced Research and Global Observation Satellite, which was launched by the Air Force in February of this year [1999], for a minimum of one-year mission duration. Now, for that kind of mission, we definitely need an electronic readout device to send data down remotely to the ground because of the fact that you don't have astronauts there to bring it back, you don't have the Shuttle to bring it back, and so the satellite's up there permanently. You have to radio the data down, just like the Hubble Space Telescope does. The basic distinction is that the charge couple device takes the place of the film to record the

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electrons, so that you get a signal that can be processed by telemetry and sent down to the ground as an image, just like in the HST [Hubble Space Telescope].

S

WANSON

: I suppose one of the advantages of that is that you have instantaneous results, you

don't have to worry about retrieving the film and then processing it, and so forth.

C

ARRUTHERS

: Right. And also it's more quantitative, because with the advances in computer

technology, we can convert CCD images to light intensity much more readily than we could convert film images into light intensity.

S

WANSON

: The instrument, as it's deployed on the Moon, it's basically housed in the descent

stage on the lunar module, and then hauled up by the astronauts?

C

ARRUTHERS

: That's correct. It had to be in a protective bag to keep the inside of it dry,

because one of the problems we had in all of these cameras is that since they are designed to be open to the vacuum of space, we have to protect them from being contaminated when they're on the ground, and, in particular, water vapor is a big problem, so we have to put them in dry bags, make sure they're purged with dry nitrogen and that sort of thing.

S

WANSON

: Earlier this week, we were at the [National] Air and Space Museum attending a

conference, and we noticed one of these instruments on display there, and they had a sign next to it, describing it as a backup instrument. How did that come about, bringing it out to display? Because I don't remember seeing that a while back. I don't know if that was relatively recent or not.

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C

ARRUTHERS

: Well, actually, Dr. David DeVorkin at the Air and Space Museum had

requested the backup of the Apollo camera as a possible display item. The backup unit was used for the actual display on the lunar module exhibit at the Air and Space Museum. It turns out that the film transport, the actual film transport that's on that display model, is the actual flight one from Apollo 16, which was brought back there by the astronauts. We don't advertise that to the public, because we don't want somebody to steal it and try to sell it for a million dollars, just because it had been to the Moon and back.

S

WANSON

: So they had this in storage, the backup, for a number of years here?

C

ARRUTHERS

: Yes, right. The actual camera from the backup module was used in Skylab,

so we had to remake a model of the camera for the display at the Air and Space Museum.

S

WANSON

: The only difference then was that instead of the tripod when it was on Skylab, it

was attached to--

C

ARRUTHERS

: To an airlock.

S

WANSON

: One of the things that we were talking about earlier was, you attended this

conference or seminar that was held yesterday at American University [Washington, DC], and we were talking about your feelings of manned or robotic versus unmanned, human space flight. I was wondering if you could share what your feelings are and the differences between them, and what one can accomplish versus the other, and if you have a preference of one over the other.

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C

ARRUTHERS

: Well, that's one of the things that's changed a lot over the years with the

advances in technology, because one of the justifications for the Space Shuttle back in the seventies was that it would provide human presence for carrying out experiments in low Earth orbit that would not be practical to do robotically with unmanned satellites. However, with the advances of computer technology, we've seen a shift over the years in that many of the experiments that originally would have only been practical with human presence are now practical to do remotely with robotics. For example, the Mars Pathfinder was a good example of how miniaturized electronics can do almost as much in a hundred-million-dollar mission as a billion-dollar Viking mission of 1976. There are still some things that really require the human presence, but in the area of astronomy, the shift has been largely toward the robotic techniques, and that's also evident in our changing over from film to the CCD recorder, so we can have it in an unmanned satellite, long-duration mission, as opposed to short-duration missions like the Space Shuttle and Apollo.

S

WANSON

: When you were working on the Apollo Program, were you aware at all of the

significance of the work that you were doing, beyond just its scientific return, but more because you were being a participant in the race to the Moon and just being involved with the Apollo Program?

C

ARRUTHERS

:

Yes, I think that, as was mentioned by several people at the Space

Symposium at American University, Apollo was sort of unique, in that it was driven by the race between the United States and the Soviet Union to be first, and once that race was won, and also, again, once the Cold War was over, the competitive urge decreased and, therefore, there was less pressure on getting things done quickly and more pressure on getting them done cheaply, and that's the reason for the better, faster, cheaper approach nowadays, in that

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faster is faster simply because it's smaller and cheaper, not because there's more time available or less time available to do it. The advances in technology, particularly computer technology, have made it possible to do things better, faster, and cheaper. It's not really just because somebody said that this is what we want to do. It's just that it's been more practical to do it nowadays better, faster, and cheaper, as opposed to the old approach of having a billon-dollar spacecraft with twenty instruments on it because you only get one chance to go to Jupiter, for example. Now, the drawback of all of this, in comparison to the Apollo Program, from our point of view, is that, as I mentioned, we had a tight time scale for the Apollo Program, but also there was adequate funding to carry it out. Nowadays, it's much harder to find funding for these things, and the time scale is determined by the funding, to a large extent. So even though in principle you might be able to do something fast in practice, things tend to drag on because of the fact that the time that it takes increases when funding is tight. So I guess it really amounts to the Apollo Program being a unique thing in the space program over the years.

S

WANSON

: Yes, money wasn't really too much of an option. It was more of whatever it

takes to get it done, and done quickly. Did you ever feel that during your work with Apollo and your subsequent work with NRL, that you had any additional obstacles because of your race?

C

ARRUTHERS

: No, I don't think I had encountered any particular obstacles from that point of

view at NRL, or even when I was in graduate school at the University of Illinois. One of the things that's different nowadays is that there is more of an incentive for professionals to participate in community outreach activities to try to get students, and particularly those of underrepresented minorities, interested in science, because now the general public knows that

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there is a shortage of technically trained scientists and engineers, especially among the underrepresented minorities, and the best people to serve as role models for those are ones who have already been successful in that area. When I was their age, I had no role models because nobody ever publicized them, not that they didn't exist. George Washington Carver and Percy [Lavon] Julian and others had preceded me in science, but nobody ever publicized their accomplishments, and, therefore, many of the minority students didn't know that they had a future in science because they figured it was something that was not for them. So one of the things that I try to do is to help students get involved in science and engineering by showing them that it's really fun if you get the right background in school.

S

WANSON

: Tell us a little bit more about some of the current outreach that you're involved

with. I understand from the display at the Air and Space Museum, plus reading some of your background material here, that you are quite active in mentoring and working with other students.

C

ARRUTHERS

: Yes. Well, actually, the video that's on display at the Air and Space Museum

in connection with our exhibit there involves one of our students who came to us through the Science and Engineering Apprentice Program, which is an eight-week summer program which is free of charge to the mentors, and allows students to come in and work for eight weeks in a laboratory such as ours, in either engineering or science. We've had several students over the years. In fact, the most advanced one, which we had as a high school student in 1985, I believe, went to the Air Force Academy and is now a captain in the Air Force. And we've also had a student who was in the program at American University last night, Marja Matthews [phonetic], who's a senior at Anacostia High School, has not only been a participant in the Science and Engineering Apprentice Program, but also

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in several of our other education and outreach activities, including the Moonlink Program, which is spons