Oral History Transcript — Dr. Horace W. Babcock
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Horace W. Babcock; July 25, 1977
ABSTRACT: This interview begins with a discussion of Babcock's childhood and youth around Mt. Wilson Observatory, with comments on father (Harold D. Babcock), Walter S. Adams, and Edwin P. Hubble. Also discussed in this interview: education at Caltech, University of California at Berkeley and Lick Observatory (1934-1939), and at Yerkes and MacDonald Observatories; work at MIT and Caltech on World War II hardware; astronomical instrumentation work, especially postwar Mt. Wilson-Palomar diffraction gratings; discovery of magnetic stars and studies of variations; work on solar magnetic fields (with father) and theory of solar cycle; comments on cosmology; discussion of Mt. Wilson and Palomar Observatories since the 1920s, especially under Ira Bowen's and Babcock's directorship (1963); internal administration; staff relations; dealings with Carnegie Institution and Caltech; discussion of Hale Observatories, 1930-1977; role of government funding in astronomy; guest investigators; allocation of telescope time; planning, funding, and construction of the Carnegie Southern Observatory at Las Campanas, 1963-1977. Also prominently mentioned are: Philip Abelson, Ed Ackerman, Carl David Anderson, Wilhelm Heinrich Walter Baade, Patrick Maynard Stuart Blackett, Vannevar Bush, Subrahmanyan Chandrasekhar, Crawford Greenewalt, Jesse Leonard Greenstein, George Ellery Hale, Caryl Haskins, Louis Henyey, Armin O. Leuschner, Nicholas Ulrich Mayall, Charles Edward Kenneth Mees, Paul Merrill, Rudolph Leo Bernhard Minkowski, Edgar Nichols, Elmer Prall, Bruce Rule, Frederick H. Seares, Sinclair Smith, Otto Struve, Charles Hard Townes, George van Biesbroeck, H. A. Wood, Fritz Zwicky; Astronomical Society of the Pacific, Astrophysical Journal, Bausch and Lomb Co., Eastman Kodak Co., Ford Foundation, Hale Observatories, Hale Solar Laboratory, Inyokern Project, Kitt Peak National Observatory, Las Campanas Observatory, Lick Observatory Bulletin, McDonald Observatory, Mount Wilson and Palomar Observatories, National Science Foundation (U.S.), 48-inch Schmidt Telescope, 100-inch Telescope, 120-inch Telescope, 200-inch Telescope, and University of California at Berkeley, CA.
Weart:The first thing I wanted to ask you about was your father, Of course, usually the first thing I ask people is, how did you get in terested in astronomy? In your case I suppose thatís fairly clear, But I still would like to know about your father, and how you first encounter ed astronomy. At what point you began to become really interested in it.
Yes, Well, of course, my father was trained really in electrical engineering, but after a year at the National Bureau of Standards there was some contact with George Hale, Hale invited him to come here essentially to work in physics, or at least on the physical side of astronomy. Anyhow, Dad joined the staff in 1909, so as a small boy I grew up in this atmosphere. We were close to the observatory, and many of my early recollections relate to Mt. Wilson, seeing staff members and astronomers, and being aware of the construction of the instruments on the mountain.
I remember the noisy riveting of the l00inch dome, for example, when I was a very small boy, and I remember several members of the observatory group in the era of l9l5-19l8: van Maanen, Ellerman, St. John, Louise Ware, Tom Nelson, Jerry Dowd. So it was only natural that I would have an early strong interest in astronomy. However, I also was interested in engineering, and I was rather torn on the decision between astronomy or a career in engineering, until I was well into college. In fact, I actually graduated in structural engineering, although with a pretty strong background in physics and the like, So it was after I graduated from Cal Tech in 1934 that I really decided to go into astronomy, and went up to University of California at Berkeley for that.
Weart:Where did your interest in engineering come from?
Babcock:Iíve always had a strong interest in instruments, and things in the engineering line. I had a somewhat distant relative who had a fine career in engineering. Most of my classmates were studying engineering rather than science, I was fascinated by fine mechanisisms, and by optical and electrical instruments.
Weart:By the way, did you have brothers or sisters?
Weart:So you spent a lot time with your father, then?
Babcock:Well, a fair amount of time with my father, Frequently. when I was quite young, my parents would take me up the mountain. Thereís a cottage up there available for use of staff, which we all enjoyed, Later I did a good deal of hiking around the mountains, when I was in the Scouts; my Scoutmaster was Seth Nicholson who was on the staff here, so there were many associations.
Weart:Tell me, what kind of person was your father? How did he seem to you, while you were growing up?
Babcock:My father had a most unusual appreciation of Nature, of the physical world. With great patience he developed my interest and curiosity in these things. I valued his advice and his opinions very highly. In retrospect, I think, he took an unusual interest in me, perhaps more than many sons enjoyed, For example, he introduced me to photography. When I wanted to build my own 6-inch telescope he gave me a good deal of assistance, He provided me with tools, and so on.
Weart:You were grinding your own lenses and so forth? Mirrors?
Babcock:I made a couple of mirrors and a quartz lens. On the other hand, my father was quite careful never to try to make major decisions for me. He left the decisions to me, but he tried to show me where the opportunities were, where the interests might lie. He had lacked much formal training in astronomy, and his studies at the University of California were mainly physics and electrical engineering. He was primarily a physicist here on the observatory staff. He was tremendously impressed by George Hale, and by Haleís enthusiasm for science.
Weart:He admired Hale.
Babcock:Yes, Dadís associates were very largely people right here at the observatory. And I at least had the opportunity to have some sort of acquaintance with many of the observatory staff, even when I was just a boyó
Weart:I see, What was your motherís background?
Babcock:Her grandfather was a sea-captain who settled in San Francisco in the l85Os; her father was in business, Mother was born in San Francisco, and grew up in the city of Berkeley, She was, I would say, of a fairly strong religious background. She had many friends associated with the University, although she herself is not a graduate. She had no particular background in science.
Weart:Did you have any formal religious training while you were growing up?
Babcock:I was enrolled in Sunday School and for a number of years I attended fairly regularly, But that didnít continue to be any very strong influence with me, after school age.
Weart:I see, Your father was not a strong religious person?
Babcock:Not in the formal sense, No, organized religion was not a strong influence with us.
Weart:I wanted to ask you some questions about going to school here and so forth. Was it a fairly automatic decision that you would go to Cal Tech for school, or did you consider going other places?
Babcock:Cal Tech was a fairly automatic thing, At least when I was younger and began to think about college, the idea always was, well, it would be great if I could enter Cal Tech, and that was the thing to aim for. Also, my best friends in high school were interested mostly in engineering, and they had aims of going to Cal Tech as well, So that seemed to be the obvious thing to do.
Weart:Were there any other astronomy students, or students interested in astronomy, when you were going there?
A few, But astronomy had not yet become organized at Cal Tech in the early 1930ís. In fact, there was no instruction offered for under graduates. But there was of course a lot of interest in the 200inch telescope, which was getting a great deal of publicity in those days. I was so much interested in astronomy that I unofficially went to the extent of putting up a petition on the bulletin board.
I suggested that those interested in trying to organize an introductory course in astronomy might sign below, with the idea that I would turn it in to the Dean and see if something couldnít be done. I got a large number of signatures, I still have that original paper, with perhaps something like 60 to 80 names. And as a matter of fact, a year later there was an introductory course offered, Possibly my petition had something to do with it.
Weart:And you took that course.
Babcock:Yes, I sat in on it. It was given by John A. Anderson and one or two others who were on the observatory staff.
Weart:Did you go any farther than that, or was it just this one introductory course? Were there any special courses, study groups, anything like that?
Babcock:Not at that particular time, It was clear that Cal Tech was going to have to develop a department of astronomy or something of that sort, anyway, It was bound to come. It just took a little nudge to get things started.
Weart:I see, Were there areas outside science and engineering that interested you, philosophy or anything like that?
Weart:I was pretty well aware of biology, and gave it some thought. I had an uncle, Ernest B. Babcock, professor at the University of California, who was a botanist and a geneticist. He gave me books and made certain that I know something about biology, But I wasnít really inclined enough that way to think of it seriously.
Weart:I see. What sort of an education did you get, preparing you for astronomy here? In physics and so forth?
Babcock:The undergraduate work at Cal Tech, at least in those days, was not differentiated to any great extent, One got a pretty heavy introduction to physics, math, and chemistry with exposure to the humanities. When I got to the junior year I had a few electives, and I did take introductory work in theoretical physics from Houston and a course in differential equations from Bateman, and the like. Of course, this was obviously what one might think of, in preparing for work in astronomy. But it was also clear that Cal Tech, at least in the 1930ís or middle thirties, was not going to have a graduate school of astronomy, so that I would have to go elsewhere, And presumably that meant Berkeley. Thatís the way it worked out.
Weart:I noticed that even before you graduated, you did have a couple of papers in PASP, with your father, on—
Babcock:Yes, on the solar spectrum.
Weart:Chromospheric lines; you used the 150 foot tower.
Yes, I had a most unusual and valuable opportunity there. In 1932, mainly through Dadís interest, I was offered a chance to be a volunteer observer on Mt. Wilson for the summer. So I spent some eight or ten weeks up there, even while I was just a sophomore in college, and I was able to repeat this in 1934 and 1935. I had a scientific assignment. I was to observe the flash spectrum of the solar chromosphere with the 150 foot tower, in the early morning, when the seeing was good. So every morning I got up early, and made these observations.
This gave me a chance to be there at the ďmonasteryĒ, (the lodge on the mountain), and to have some acquaintance with the astronomers, all the observers who came and went, This was really a valuable opportunity, I often think back to the various people that I became somewhat acquainted with in those days: C,G, Abbot, S,A, Mitchell, Joel Stebbins, Sinclair Smith, Joy,Merrill,Humason, F.E. Wright, Hubble, Baade, Adams, Durham, Pease, Thackeray, J.S. Plaskett, etc. In fact even before that, I think it was the swmner of Ď28, 1 did some volunteer work in the optical shop at Santa Barbara Street and made a lens or two, That was valuable initial background also, But spending those summers on the mountain was a most unusual oppor tunity. It was a most interesting chance for me to participate in some of the observatory operations and to hear ďshoptalkĒ, including plans for the 200-inch.
Weart:These were people perhaps that you had met before, but hadnít had a chance to talk with?
Babcock:I had met many of them before, But having meals with them almost every day on the mountain was a different sort of contact. To listen in on the conversation of working astronomers, when they talked about their research and about the instruments and about astronomy, was fascinating.
Weart:I see, Did any of the people, the staff members here other than your father, have a particular influence on you.
Babcock:Yes, to some degree, at least, Sinclair Smith and then John Anderson had some influence, as well as Seth Nicholson. They took an interest in me, and gave me pointers here and there.
Weart:Iíd be very interested if you could tell me anything in general about the observatories in the 1930ís, about the sort of environment that was here. There arenít very many people still around who had the kind of contact with it that you did. Did you know whether there were definite groups for example, the nebular or the spectrographic group?
The Mt. Wilson Observatory was one of several Departments of the Carnegie Institution, with administrative control from the head office. Local administration was concentrated in the hands of the director (W.S. Adams), Staff members had maximum time and freedom for their scientific work, which centered around observing assignments with the telescopes. In addition to the groups you mentioned, there was the solar group and the physical laboratory group.
Mainly, the observatory group of astronomers here was an integrated observatory, if I can use that term. And the staff had the great advantage of access to the best big telescopes in the world at one of the best locations. It was a pretty fully coordinated group. Of course, there were some personality clashes and some internal friction, but things got along reasonably well. The director did a job of directing, almost entirely by himself. Frederick H. Seares was the assistant director, and he had certain responsibilities that he handled very well indeed, And there was a secretary Joy had this function for a long time, he handled certain responsibilities, And Adams had a bookkeeper to help him, But the administration in those days was, I think, comparatively simple and straightforward. The decisions were referred to the director, and he made them, and the scientists stuck to doing their research. That was the way it went.
Weart:Did the director make any scientific decisions, like allocation of telescope time?
The director, in consultation with senior staff, made general allocations of telescope time. Joy did the scheduling. In those days, the competition for dark telescope time was not so evident as it is now. Telescope time was assigned not so much on the basis of formal proposals and requests. If you expected to get three nights in January and wound up with seven, why, you just went up and took your seven nights. I mean, this was an assignment that you were glad to carry out.
The director participated in many very small decisions, about how many plates would be stored on the mountaim in each dark room and so on and so forth. Since the director controlled all of the available funds, his decisions were most important. However, Mt. Wilson Observatory was operated in a less dictatorial fashion than Lick Observatory or Yerkes, But the director really directed.
Weart:Why was that? Was that because of Adams personality? Or because of some other reason?
Babcock:It was partly Adams personality, that he wasnít inclined to be a dictator, Whereas the tradition of having a very strong director was even more marked, I think, at Lick, and it appeared to be so at Yerkes, when I arrived in the late thirties. That was partly Struves personality.
Weart:He operated more on the old German model.
Weart:Or Russian, perhaps. But Adams did not operate on this model, as Struve did, of suggesting to people that they should work on such a problem?
Babcock:A staff memberís field of scientific investigation was mapped out in discussions with the director. There were many consultations. I think Adams was not inclined to make many strong decisions in that area, but he controlled the funds for instrumentation and purchases. There was a certain balance that had to be attained somehow among the senior staff: Hubble, Baade, Merrill. There was rightfully much attention given to designing and constructing the tools and instruments that the staff needed, the design group, the instrument shop, and the optical shop were important. In the 1930s and 1940s the 200 inch telescope project brought increased attention to planning for research.
Weart:After the war or even before the war?
Babcock:Both, With or without the committee, there was much useful discussion, Baade, of course, was a very strong-minded character and probably didnít want to just adopt Hubbleís ideas in these areas. Bowen and Minkowski were influential.
Weart:I understand. Were there any disagreements on what sort of scientific problems should be followed, in cosmology, programs?
Not serious disagreements, although there were different priorities and viewpoints. There was a strong feeling that the red shift business had to be pushed and that it was very necessary to develop spectrographs to make the best progress on this work. So there were contacts without side groups. The Rayton lens was brought in (about 1930), and instruments were designed and put into use that were intended for spectroscopy on very faint objects.
The actual observing was tedious in the 1920s and l930s. Humason was willing to undertake this and spent vast numbers of nights pursuing it very effectively. There was recognition that photometry was vitally important. Seares devoted his major professional work to stellar photographic photometry, trying to extend the magnitude sequences photographically. This field really awaited photoelectric photometry, which was being developed; the work of Stebbins and Whitford was fundamental, much of it at Mt. Wilson. Everyone realized that progress depended upon evolving a progression of new and better instruments.
Weart:I understand, it was a great problem in those days with the photo graphic film.
Babcock:Yes, The importance of photography was clear and important collaboratron or cooperation was developed with the Eastman Research Labs, Dr. C.E.K. Mees, who was director of the Eastman Research Laboratory, was most helpful here, and he saw to it that a great deal of effort from Eastman Kodak went to developing emulsions that would be of use in astrophysics.
Weart:Yes, I noticed that in your 1932-34 papers, you used a special Kodak infra-red emulsion.
Babcock:Yes, the type Z emulsion.
Weart:You would talk with him about what your needs were and so forth? Mees had many talks over an interval of about 30 years with Hale, Adams, Merrill, H.D. Babcock, A.S. King, and others; he retired soon after in 1946 when I joined the staff.
Babcock:The whole array of Eastman emulsions began to proliferate in the l930s. It remains highly important to astronomy, I imagine that Eastman never has made very much of a financial success of that, but the company made a real contribution to science. Hale was so interested in photography that in the early days, (1915-20) he seriously considered setting up an emulsion development laboratory here, But it didnít come about that way.
Weart:I see, Fortunately he didnít have to, because they did it.
Babcock:Eastman did it.
Weart:Tell me a little more about the environment here. Was there a regular seminar that people attended?
Babcock:There was a regular series of meetings known as the Journal Club, which met every Monday at 11 Oíclock, generally over in the ďgovernment buildingĒ, Essentially, this was so that each staff member could give the others an account of what he was doing. Talks were given in rotation among the staff.
Weart:Did you sometimes go to those?
Babcock:Yes, There were, of course, occasional lectures by outsiders, Sometimes visiting astronomers would participate in the journal club, but the big names from outside tended to give seminars or colloquia down on the Cal Tech campus. Iím thinking of H.A. Lorentz, who came in the early twenties. Then there was Ehrenfest, who had quite a big impact here. He came, Iím sure, more than once, and gave talks, which were well received. It was difficult for active research astronomers to keep up with the current advances in physics and spectroscopy, quantum theory and the like. There was all too little opportunity to be current in that. So the lectures by visitors were important. There were a great many other visitors: Kapteyn, Turner, Lundmark, Abetti, Jeans, J.S. Plaskett, Michelson, C.G. Abbott, Oort, Wooiley, etc. etc. H.N. Russell of Princeton visited frequently; he was a Research Associate for many years. Einsteinís visit in 1931 was important. Sir James Jeans was a Research Associate.
Weart:Were you taught quant1n physics as an undergraduate at all?
Babcock:As an undergraduate, only a little. There was something in atomic structure, I had some introduction to methods of theoretical physics under Houston and Bateman. But any quantum physics I got came later at Berkeley, except for some seminars by such men as Epstein, J.R. Oppenheimer, and Bowman.
Weart:How about relativity?
Babcock:Aside from a few lectures by Tolman and maybe Epstein, no, there wasnít much that I was exposed to as an undergraduate.
Weart:Did people from Santa Barbara Street get down to the campus much? Was there much interaction with the physicists there?
Babcock:There was a fair amount. There was the Astronomy and Physics Club. In particular, there were special lectures in the early twenties, Youíll still find in Bridge Lab, halfway up the stairs from the ground floor, two little group pictures on the wall showing the principal people who attended some of these lectures by Lorentz, Epstein, Ehrenfest and others. There were Bowen, Epstein, Millikan, Houston, DuMond, and Smythe from Cal Tech, and a few from the Mount Wilson Observatory like Adams, A.S. King, Stromberg, John Anderson, Sinclair Smith, Harold D. Babcock, and several others. Staff members from the Mt. Wilson Observatory frequently attended the regular Thursday afternoon Physics Research Conferences on the Cal Tech campus.
Weart:Did people get together much with the physicists, at lunch for example, as they sometimes do now, or things like that? Was there any informal coming and going.
Babcock:I wasnít aware of anything much like that. It might well have gone on, particularly after the Athenaeum (Faculty Club) was built and started to function. But in my circles, I wasnít very much aware of that.
Weart:Do you know where and how in general the staff exchanged ideas about research?
Babcock:Well, a lot of it, among the observing astronomers, occurred on the mountain. Because in those days you had the 100-inch and the 60-inch, plus the solar tower, that were scheduled every night of the year, and so there were all those observers up there, and on change days, youíd have perhaps double the number, at least for lunch.
Weart:They would get together over lunch.
Babcock:Well, lunch and in general, at the monastery on the mountain. This was certainly important. Then, there was the Journal Club that I mentioned, and there were just informal talks going on here in the offices from time to time.
Weart:Was there much after hour socializing?
There was some. At least in the twenties, and perhaps into the thirties, research was pursued in a somewhat more leisurely way than it is now, but there were fewer distractions, People played tennis; we have a tennis court out here that was used in those days. When I was a small boy, I know that about two afternoons a week, at about 4 oíclock, people would go out there and thereíd be tennis games. A few members of the staff played golf, Nowadays, that would be considered absurd, just out of character; nobody has time for those things. But in the middle twenties there was awareness of the desirability of getting more social things going.
So when the Athenaeum was built (and that was finished I think in 1925) it was strongly regarded as a meeting place not only for the faculty on campus, but people from the Huntington Library and Art Gallery and from Mt. Wilson Observatory, and there were representatives of all three groups on the governing board and the house committee and all this, So it was a focus for social activity. This is illustrated by the visit of Einstein in 1931.
There were dinners on such occasions put on at the Athenaeum and there were representatives from here, people who took an interest: Charles B. St. John as well as Hubble and some others, Abbut 1930, Charles B. St. John of the Observatory revitalized the moribund University Club in downtown Pasadena; several members of the staff and of the Cal Tech faculty became active in it.
Weart:This is all very interesting, because itís the kind of thing that one doesnít have recorded in the directorís Report.
Babcock:These are just very ordinary ideas about the way things operated in those days, but itís true, there are not very many people around who were present then.
Weart:How did people relate to Hubble, react to Hubble? What were peopleís feelings about Hubble and all the things that he was doing?
Well, Hubble was regarded as doing something very important that occupied most of his time and energy. I donít think he was much for socializing with others on the staff, He took his work very seriously, and he did it according to certain routines that to him were important. He was a very dignified person, and tended, I think, to seem a bit cold and standoffish. On the mountain, I know, in 1932 heíd get through dinner and then get dressed; heíd put on leather puttees and a beret, a regular costume that he wore when going up to observe at the l00-inch.
This was all carried out with a great deal of attention to detail and to atmosphere. I had some contacts with Hubble along in the late thirties. I had been a graduate student at Lick, and I did a thesis on the rotation of M3l, I came to Pasadena and talked with Hubble and with Zwicky and some others about it, Hubble, I think, didnít mean to be discouraging, but his attitude was so cold that quite frankly, it turned me off, I might have had a stronger interest in pursuing research in extragalactic fields, had it not been for that.
Weart:I see. That was one of the questions I was going to ask you in fact, later on, is how you sort of got turned off on that, Did he have the attitude that if it hadnít been done on the l00inch it probably wasnít that good, that sort of thing?
Babcock:Well, not exactly, I mean, there werenít any other telescopes around in the same class. Mayall was doing wonders with the Crossley 36-inch, at Lick, and I had the good fortune to have him as my thesis advisor, and so I got a very good start under Mayall.
Weart:Tell me about your decision, when you did decide to go to Berkeley, or really when you decided to go into astronomy. What sort of things influenced you? Were you interested particularly in cosmology, for example, or just astronomy in general?
Babcock:I would say astronomy in general, including instrumentation, By 1934, when I did have to make that decision I suppose there were a number of aspects to it, For one thing, the 200-inch project was under way, and it was coming along well, That was a tremendous magnet, the 200-inch and Palomar, I had been to Palomar in 1932, before anything had been built there, and I was rather taken by the primitive circumstances prevailing on the mountain and by the challenge of this big project, It was in the middle of the Depression, and some of my classmates were having a hard time getting started in engineering, although I donít think that influenced my decision very much, I think mainly, it seemed to me that astronomy and astrophysics were going to offer bigger challenges and opportunities, and that things would be happening, and there ought to be some chance to work in these areas. The fact that Iíd had these summers on the mountain, where I could learn more about astronomy and about the people around here — this was important, So I made the decision then that I wanted to go ahead and do graduate work and get a degree in astronomy, and I had no particular qualms about that decision at the time, It was pretty evident.
Weart:So your picture of your future career would have been somebody using a large telescope looking at something or other.
Babcock:Certainly large telescopes were very important in the picture, yes.
Weart:I see, Tell me, did you ever read much science fiction?
Babcock:No, itís never had much appeal for me.
Weart:I suppose you got your astronomy mainly direct from astronomers, rather than from popular literature or high school teachers or anything like that?
Babcock:Yes, thatís true.
Weart:Aside from your father, how did the rest of your family feel, your mother, other family members, about your decision to become an astronomer?
Babcock:My mother was quite pleased about it. I remember her attitude, a number of years earlier, when I was probably about entering high school and my mother and father and I happened to be up on the mountain. We were looking at the 100-inch telescope, and my mother just dropped some comment, ďWouldnít it be great if you could use this some day?Ē I thought, thatís hopeless, Iím just a kid, I would never have any chance to get to the point where I could use the 100-inch, But anyway, my father and mother Iím sure were pleased with this.
Weart:I see, How did you choose then to go to the University of Califor nia, up to Berkeley?
Babcock:Well, if one wanted to go to a graduate school in astronomy, it was almost the only place on the West Coast. I didnít have much inclination to think of going to an Eastern university, which would not be strong on observing anyway, The University of California had the Lick Observatory, and it was the place to go.
Weart:I see, How were you supported while you were in graduate school?
Babcock:My father provided me support almost entirely while I was at Berkeley. I spent three years in Berkeley getting through the necessary course work and passing my prelims. I was a teaching assistant there for perhaps a year, and this might have brought in a very small supplementary income. Later after I went to Lick, I had some sort of a fellowship that helped out a bit there, But of course, expenses in those days were at a very low level, compared to what they are now.
Weart:How did it come about, your going up to Lick? You did this thesis under Nicholas Mayall, on the rotation of Andromeda, How did you get a relationship with Mayall? How did you arrive at this particular problem?
Babcock:Well, when the time was getting close where I might think of going to Lick to do an observational thesis, naturally I was encouraged to come up with a few ideas, and it was only natural to talk to people, I remember talking to William Wright and James Moore and Art Wyse and Nick Mayall; I was rounding up some ideas. Mayall at that time had recently completed a very useful nebular spectograph that he built for the Crossley, and he was putting it to work, He virtually offered me an opportunity to use that, One of the obvious problems around, that I knew about, was rotation of galaxies, It seemed to propose that sort of thing, and step into it.
Weart:He sort of proposed the instrument and you proposed the problem?
I think Mayall proposed the problem. You see, at Mount Wilson Pease had done some work on the extreme central region of M-31. It seemed that this could be extended, and Mayallís spectrograph was pretty well suited to the jobs. When I was first discussing the idea, there was a question as to whether one would be able to get enough new information to make it worthwhile. If one confined the work to the diffuse central region, the nucleus, one couldnít expect to work out very far from the center.
And the idea was to push it as far as possible, not only with the Crossley but using even a smaller, shorter-focus telescope to get better seale. Then the suggestion was (and this probably came from Mayall) that I should look for what we now call H II regions, with the idea of getting bright-line emission nebulosities, that could provide velocities, This worked, very fortunately, and so enough came out of it to make a really significant advance.
Weart:You could really find out what was happening further out from theó
Babcock:yes, you could go way out, to 1-1/2 degrees from the center of M-31.
Weart:I see. That must have been quite exciting for you actually, to see this thing behaving in a strange way.
Babcock:Yes, I remember being impressed by that at the time—about the time I plotted up the results of this, (gets article from shelf) I had measured all these plates, and I came up with this array here.
Weart:Thatís the LICK OBSERVATORY BULLETIN, hereó
Babcock:Yes, this is the LICK BULLETIN. These small dots in the middle represent the unresolved nebulous region, but the bigger circle things here represent the exterior regions. I remember when I plotted this up, I thought, ďGee, this is something—Iím the only man who knows really how this thing rotates far out.Ē And I was aware this is quite a thrill. This is something that provides a real reward for working in astronomy. Perhaps I had three or four similar occasions when I had that kind of feeling, I thought that, at least to me, was significant.
Weart:You had really made a discovery. I see, I should ask you a little more about your education at Berkeley, before you went to Lick. Who were the professors that had the most influence on you? What kind of an education did you get in astronomy?
Babcock:The Berkeley astronomical department, at that time, was a post-mature organization, with old professors who were specialists in celestial mechanics, Leuschner was the director. The big names were Tracy Crawford, and then there were Einarsson and Meyer. Shane was a professor at that time, but he was the only astrophysicist in the group, and the traditions were all along the line of celestial mechanics. Much of the work that graduate students were supposed to do related to fundamental astronomy and orbit theory. We all had to learn how to compute orbits using a desk calculator. They would admit that; we didnít have to use log tables.
Weart:I see, you were allowed to use the hand-cranked calculator.
Babcock:Yes, Well, even electric, in those days. But the emphasis was all on learning how to do a very thorough job, being acquainted with the main theories of orbit computation, that is, Laplacian theory and the Gauss theory, and then the methods of going through the calculations, Leuschnerís method and the like. We really got a thorough grounding in all this, Leuschner said as much - ďYouíre going to learn to be thorough, and to know exactly what youíre doing. At the same time, you should be getting something in astrophysics.Ē He was ready to admit that a lot of the future advances would be in astrophysics. So we had courses over in the physics department, there was spectroscopy and optics and introduction to quantum theory and so on, and of course this was all to the good.
Weart:You were encouraged to take these, or even required to take them?
Well, it was essentially required unless one wanted to be a specialist in celestial mechanics, and very few people were doing that, Herget, Sam Herrick, and one or two others did that, But of course, Shane also gave a course in modern astrophysics; he also gave a course in celestial mechanics. But then there were courses over in physics, given by Birge, in optics, and there was spectroscopy, by Francis Jenkins, Harvey White gave a regular course in optics.
And perhaps equally of interest, J.R. Oppenheimer was around there in those days, and he gave occasional talks or lectures on theoretical physics. I would always go if I could, even though I was not specializing in that field; he was such a marvelously articulate lecturer that I enjoyed just hearing him talk, and I could pick up something of what he was thinking about, I had some courses also in quantum mechanics and the like.
Weart:What about the other graduate students? How did they react to this regime?
Babcock:They adapted to it pretty well, I mean, it was about all you could do. We spent much more time in celestial mechanics than was really going to be very useful. But still we got exposed to a lot of current physics, so it wasnít too bad, And there was some math on the side,
Weart:I see, Did you get together with the faculty at seminars, journal clubs, that sort of thing?
Yes, There was a weekly seminar sort of thing, and occasionally of course the graduate students would be called on to give the main part of the talk. There was some interaction with Lick Observatory. But here it was evident that the University had a department of astronomy in Berkeley, and it operated an observatory on the mountain, and the two were separate and rather distinct organizations. Things were not entirely smooth. The observatory, under William Wright as director, was doing research, and there was a very distinct difference, When you got through being a student at Berkeley and went to the mountain, you were taking up a different life, with different people.
There was some mixing back and forth. For example, the astronomers from the mountain were encouraged occasionally to spend half a year in Berkeley, and some of them did, James Moore did, Trumpler did, But it didnít get very far. There was no unification of the two groups, and none should be expected. An academic department is one thing; a major observatory is something else. Iíve noticed, in other organizations, there is still this tendency, that you can only with great difficulty mix an astronomy department engaged in academic affairs and teaching— itís very difficult to mix that with the business of doing research with a major mountain observatory.
Weart:I should ask before I forget, did many of the other graduate students also go to Oppenheimerís seminars and so forth? Or any of the physicistsí seminars?
Babcock:Some of them went rather regularly to physics seminars. I may have been a little more taken with Oppie than some of the other astronomers were.
Weart:Did any of the physicists ever show up at the astronomersí meetings?
Babcock:Rarely, But I may interject that Edward Teller showed up when, about 1952, I gave an invited seminar on magnetic stars at the Berkeley Astronomy Department.
Weart:Tell me now about this transition to the mountain. How did you meet Mayall and get to be his student anyway? He was on the mountain and you were in Berkeley.
Babcock:Right. Well, there might have been a few occasions when he would come down, maybe to attend some lecture or what not on campus, But in 1937, which was my last year in Berkeley. I had a few opportunities to go up to Lick and maybe stay overnight, or at least go up, look around and get slightly acquainted. So quite naturally, I made the acquaintance of Nick Mayall and Art Wyse and some of the others up there. I probably met Mayall before that, rather casually here in Pasadena, because he was employed here at Santa Barbara Street as some kind of an assistant in the early thirties.
Weart:He spent some time here?
Weart:What sort of relations did Lick and Mt. Wilson have at that time?
Babcock:Oh, very cordial, Not particularly close, But thereíd be occasional visits, you know, Somebody from Lick would come here, somebody here might go up there, But mostly, the interaction was at, say, meetings of the ASP or American Astronomical Society, Those meetings, I think, were the occasions for really getting together, The meetings were important to observatory staff members in the 1920ís and 1930ís; less so in later years. The Lick astronomers of course lived with their families on the mountain and formed a pretty c1ose-knit group, although with subdivisions or factions; they were so close that everybody knew just what was going on in all their families. Here, the families are dispersed around the Pasadena area, and there wasnít anywhere near the amount of socializing that you found at Lick. So there were some misunderstandings resulting from that, But profession ally, I think the interaction was good.
Weart:As to the scene on Mt. Hamilton, comparing it with Mt. Wilson was there any difference that you noticed in the scientific orientation when you went there? Did they seem to be doing things in a different way, or doing a different kind of thing?
Babcock:Well, what they did depended very heavily on the available instrumentation, They had the 36-inch Crossley and they had the old refractor, and not much else, A l2-inch. So there were efforts to do things that were useful, keep the old 36-inch refractor productive, and it was getting pretty tough. Mayallís work with the Crossley, with his new spectrograph, was a real shining example of achievement, with not very much substance (to work with). There were people there sort of holding onto careers that had begun earlier. There was Neubauer and there was George Paddock, who could hardly he called productive. There was Hamilton Jeffers, who was a very good positional astronomer, and nobody was better at picking up comets or getting out accurate positions and so on. He was rather narrow in his interests, but still underrated.
Weart:Was there much interest in extragalactic nebulae and cosmology, on the mountain?
I donít recall much, except what Mayall was doing, Mayall had collaborated with Hubble, or at least was pretty close to what Hubble was doing, Hubble was making, with the Mt. Wilson equipment here, his survey of the distribution function of the magnitudes of galaxies, and Mayall under took a similar job with the Crossley. While I havenít thought about this for a long time, there were valid reasons for Mayall to undertake it, At least it was independent of the Mt. Wilson effort, and even though his equipment was a good deal smaller, it was, Iím sure, a very worthwhile and useful activity.
At the same time, Mayall was getting into the spectroscopy of interesting extragalactic objects with his spectrograph, and he was turning up things of real interest. I remember, when I was just a graduate student there, his showing me photographs and spectra of blue star-like galaxies. He said, ďThose things are really interesting. If we just had a little more power, Iíd sure like to really get to work and do a more thorough job on those things.Ē He was into compact galaxies. There was nothing you could Identify as a quasar, but if he had had the bigger telescopes, why, he might soon have been into these things. Mayall obtained spectrograms of many peculiar galaxies, and I believe, recognized the importance of ďSeyfert galaxiesĒ long before Carl Seyfert published a list of them.
Weart:You give me a feeling that he was almost frustrated by being stuck with a small telescope.
Babcock:Well, you see, this frustration undoubtedly was part of te foundation for the Lick 120-inch that came along later. There was talk about that for a very long time before it could be realized.
Weart:Did Mayall have a lot to do with that? Weíre jumping ahead in time but Iím curious.
Iím sure that he did, although C.D. Shane was perhaps one of the most influential prime movers in getting the 120-inch. It was Mayallís research that formed the obvious basis for work with the telescope, and I seem to recall that he had a lot of responsibility for seeing that the 120-inch telescope was finished to high standards of performance.
Bowen, who was director here at that time, assisted in every way that he could to help Lick bring along the 120-inch, Bowen set up our optician, Don Hendrix, who was a very talented fellow, Hendrix did a lot of work for months, I think more than a year, up there. The testing of the optics was Mayallís responsibility. So in combination with Hendrix and with a lot of advice from Bowen and others, I think it was Mayall who saw to it that the optics of the Lick 120-inch were good, and that it was done right.
Weart:The existence of the 120-inch (weíre jumping ahead) did that change the relationships between Lick and Mt. Wilson?
Babcock:I think it brought about more interaction. Of course this was in the fifties, when the 120-inch got to be in operation. Yes, I think the operation of the 120-inch did increase the amount of interaction between Lick and Mt. Wilson. By that time, things were loosening up anyway. There were more things happening, there were more graduate students around, the Berkeley department was changing. Lick was changing. Things were different here.
Weart:How did people feel about the fact that it was a state funded thing? It was all still private here. Were there any particular feelings about that?
Babcock:No, I donít think so. It was regarded as a very good thing that there could be another large telescope at Lick, You see, even before 1950 it was one of Bowenís great aims to see to it that other large telescopes were built and put at the disposal of American astronomers. He did a great deal to push this idea and to assist the 120inch telescope project of the University of California.
Weart:I see, OK, well, to jump back then in Ď39 you went to Yerkes as an instructor. How did you learn about this position? Were there other positions you were considering?
Babcock:I received my Ph.D. at Lick in Ď38, and I was able to stay on one year more to continue work on the research that I was doing. That was on a very temporary basis.
Weart:You continued on with Andromeda?
Babcock:Yes, Letís see, it seems to me I was finishing that up, and probably had some other interests at the same time.
Weart:You might have been starting on the night sky?
Babcock:Well yes, that was a secondary activity but it did interest me, and I did do some work on the night sky at Lick. Anyhow, Wright did give me the real opportunity of going East, and I was able to give a brief report on this M-31 work at a meeting of the American Philosophical Society, (R.A. Millikan was chairman of the sessions)
Weart:Oh, in Philadelphia?
Babcock:In Philadelphia, At the same time Gerald Kron, who got his Ph.D. in the same year, went along, and he gave a paper on his work at the National Academy of Sciences. Wright was trying to do the right thing, to get us acquainted, make some of our work known. At about the same time, I was invited to the dedication program for the McDonald Observatory, when the 82-inch was dedicated, There was a very good group collected there by Struve, many international astronomers, I met Linblad for the first time, and I think Oort was there— yes, Iím sure he was, Quite a turnout, I gave a little paper at a meeting associated with that program, And I think as a result, Struve offered me a job at the level of instructor partly at McDonald and partly at Yerkes, I accepted that. I felt fortunate to have the offer.
Weart:How had the job prospects seemed before then? You say you stayed on at Lick, and before then of course was the Depression, How had job prospects appeared to you?
Babcock:Not very promising, I must admit that in the long range I had my eye on things around here, because the 200-inch was coming along and all that, But it was clear to me that I ought to get some more experience elsewhere, I wasnít particularly attracted by Eastern universities that had no equipments. So when I got the offer from Struve, I jumped at it, After all, here was the McDonald 82-inch, a very nice modern telescope, and a chance to do something with it.
Weart:Why do you suppose you were picked? Did he just hear you speak, or were there letters of recommendation and that kind of thing?
Babcock:Oh, I donít know, I think it was understood that Gerry Kron would stay on at Lick. There werenít too many of us fledgling Ph.D.ís around at that time, and I had this paper to show, In any event, he made this offer.
Weart:When you got to Yerkes, you spent most of your time at Yerkes, or
Babcock:No, I think more than half was at McDonald, But it was part of the same organization, you see, Yerkes was operating McDonald.
Weart:How would you compare Yerkes with Lick? What were your initial impressions of the differences between the places?
Struve and his personality rather dominated Yerkes, He was a very strong, extremely energetic director, and did so many things everybody wondered how he could possibly achieve it all. Yerkes was similar to Lick in that it had the 40-inch telescope and they were trying to keep it busy doing something useful, and having a hard time. The other telescopes at Yerkes were old and small and not very productive. That is why, in fact, Struve had promoted McDonald Observatory.
I think it is true that in those days, any astronomy department that Chicago had was essentially at Yerkes. A very strong figure there was Chandrasekhar, so they were strong in theory on the basis alone. Things were pretty active. They had W.W. Morgan, and Keenan was pretty active, Henyey and Greenstein were there. Whitford was not far away over at Madison Wisconsin, and so things were bubbling, and there were interesting discussions and so on. And the new results from McDonald were just coming out.
Weart:It was a more exciting place than Lick?
Babcock:Perhaps in a way, more exciting, yes.
Weart:More scientific talk? Or broader scientific talk?
Babcock:Well, there was more scientific talk. Some of it was a bit ephemeral, but there was a pretty good basis for it, and it was all very serious. Struve knew everything that was going on, he kept track of everything. He was editor of the Astrophysical Journal. And he gave opportunities, too, Radio astronomy was just beginning to come over the horizon. There were one or two glimmerings, and Struve was impressed by that. I think I had a chance then to go into radio astronomy. If Iíd wanted to do it, Iíd had more background on it, I might have gotten in on the ground floor of radio astronomy.
Weart:Was this because of Jesse Greensteinís interest?
Babcock:No, Just that here was a tremendously exciting thing, coming in from Reber, was he the one?
Weart:Yes, Grote Reber.
Babcock:And this was appreciated, to some extent.
Weart:You saw Reber?
Babcock:I donít know if I ever met him, but I was aware a little bit of what was going on, I had some interests in radio, but they were very casual, I think Struve thought my abilities in electronics were perhaps deeper than they really were. There was nothing very serious about this, but if I had wanted to go down and talk to Reber and work into that, Iím sure I might have been able to do it.
Weart:I see. A possibility.
Weart:Thatís interesting, Did you attend Chandrasekharís courses? Or other courses or seminars?
Babcock:Yes, On a good many occasions I listened to Chandra, But he gave a good many colloquia, so I was very well aware of Chandra. He was very friendly and helpful, and a very impressive figure. I mean, from the standpoint of scientific stature, Iíve always had a very high regard for him.
Weart:Where in general did people exchange ideas about science, about astronomy?
Babcock:Well, a lot of it was just informal conversations. In the offices, in corridors or meetings, I think a lot of it was just get-togethers in somebodyís office.
Weart:Was there any particular interest in any particular field? Was there interest in cosmology, stellar populations, anything like that?
Babcock:Not a great deal of interest in cosmology, no. And stellar populations as such hadnít been recognized. But there was great interest in stellar spectroscopy and in various types of peculiar stars. I know that one of the things that came up was an opportunity to collaborate with Elvey, on U Gem (inorum) stars. Then there was Keenan, who was working on stellar classification; he was of course one of the strong people in that area, and still is. I guess perhaps at Struveís suggest ions, I did a little collaboration with Keenan on some classification jobs. It didnít interest me terrifically and I didnít stay with it very long.
Weart:Was this the point where you began to become aware of some of the peculiar stars that were around, the A stars for example, or did that come later?
Babcock:Sure, I got a little acquaintance with stellar classification, and a little more idea about peculiar stars, But it was a pretty general introduction.
Weart:Did people much discuss other things, politics, philosophy, things like that?
Babcock:Well, not much philosophy, certainly. A little casual discussion of politics in the boarding house, perhaps.
Weart:The boarding house - this was with other astronomers?
Weart:Where did you stay? There was a boarding house in town?
Babcock:I had a room on the second floor of Henyeyís house, close to the observatory. Most of us graduate students and such people got our meals at a boarding house a quarter of a mile away, a Mrs. I canít remember her name, but it was the place where almost everybody ate.
Weart:All the graduate students met at this place?
Babcock:Yes, all the unattached people ate at this place.
Weart:That must have been very lively.
Babcock:Sometimes it got a little lively, But not always. (Laughter)
Weart:Sometimes you wouldnít discuss anything except some particular star oh, not even that.
Babcock:But there was a certain amount of social life, The van Bies broeck family was right there at the observatory, and they often invited in groups of students. There were some other social occasions like that.
Weart:What was it like down at McDonald? What was the setup there?
Babcock:There was a small isolated group at this new mountaintop observatory, Struve came and went, but he was there only a fraction of the time, Elvey was the resident acting director, so he was in charge, Dan Popper was there, he was a colleague of mine, He and Gerry Kron and I got our Ph.D.ís the same year, at Lick, so I knew Dan quite well. There were a couple of others, Carl Seyfert was there, But Seyfert, Popper and I, along with Elvey, essentially constituted a small resident staff. Then there were occasional astronomers who would come and go from Yerkes Kuiper, Struve himself of course, Keenan I guess.
Weart:I see, And what was the life like down there?
Babcock:Well, it was a life of isolation, 30 miles from the little village of Alpine, which didnít amount to a great deal, So there was plenty of time to get into oneís work, and not many distractions. The idea was that one would spend perhaps the greater part of the year there. Then I went up to Yerkes in December of 1939 and I had about four months there, I was doing some observing with the 40-inch, so I got my introduction to cold weather work, But mainly I recall the work at McDonald, work with Elvey and others, using the Cassegrain spectrograph.
Weart:That must have been nice, to use a good-sized telescope. That was your first time.
Babcock:Yes, except for a few nights on the Mount Wilson 60-inch in Ď38 or í39.
Weart:Was it fully operational by then? Everything working well and so on?
Well, it was operational as far as the Cassegrain spectrograph was concerned. Also one could take direct photographs. They were trying to make the coude spectrograph operational, and having a rather rough time of it. It was a prism instrument, and pretty slow and not too well designed. In fact, the Cassegrain spectrograph was not too well designed, either. About that time, Struve gave me an assignment to design a nebular spectrograph for use at the prime focus.
I wasnít too well equipped to actually carry through the complete design of this thing, but I did have access to certain elements like a Schmidt camera for it, and I was able to promote the acquisition of a grating. So I did in fact develop this thing. Then it was built by Ridell at Yerkes, according to my plans, but with some changes by van Biesbroeck, It was built remotely so I didnít have a chance to follow it. It was not an unqualified success, but it did work, and was later used by Thornton Page in quite a nice observational job on double galaxies, He got velocities of double galaxies and so computed masses.
Weart:I see. Was this your first big instrumental job? Had you done much instrumental type work before that?
Babcock:I hadnít done very much. Iíd put together a night sky spectrograph at Lick, and provided a few rather secondary instrumental setups. More or less in parallel with that McDonald spectrograph there was another one. Struve turned over to me Skelletís coronavisor, which had come over the horizon then. Skellet was an electronics engineer who had developed this device in the hope of being able to photograph streamers of the corona. The technology was a hit too primitive, but all the equipment was turned over to me, with some advice from Skellet, and I was supposed to make it work. So I put this thing together. I devised a new scanner and an improved detector, In fact, I made the first astronomical application of the electron multiplier phototube, the RCA 931, in early 1941.
Weart:I didnít know there was one, before the war.
Babcock:RCA had just put it on the market and I used one in the coronavisor, early in 1941, I put in quite a lot of effort on this, but it didnít deserve really quite all the attention that I gave it. I hurried up and I got what I could out of it, before I left in August, 1941, to go to MIT on the war work. So it was a very useful experience for me, but it wasnít particularly productive astronomically. It did produce a few photographs that probably showed coronal streamers without an eclipse.
Weart:I see. What was it like doing instrumental work in those days? Did you go into the shop yourself and turn things on the lathe? Or make rough drawings, or what?
Babcock:I made rough drawings. And as far as the nebular spectrograph was concerned, I made fairly detailed drawings. But it was some disadvantage, having to do it in isolation and a long way from Charles Ridell, the very competent instrument maker who did the work.
Weart:He did it up at Yerkes?
Babcock:He did the mechanical work at Yerkes. At McDonald we had one machinist—Vysotka—and a small, rather primitive machine shop. The machinist did most of the work on the coronaviser, but occasionally I would go in and persuade him that I could drill a few holes and whatever. It was done under difficulties, because of the limited facilities and supplies.
Weart:I understand, Well, now I guess the next question is about your war work, So you went to the Rad Lab, How did that come about? How were you recruited?
Babcock:Well, various astronomers had gone there, and others came later. Whitford I think had gone to the Radiation Lab, and Gerry Kron, and they influenced me considerahly.Here was a worthwhile effort, it had good sponsor ship, it was growing, the opportunities to learn a good deal were there, This was of course before the United States got into the war, I was thinking seriously about this in the spring of Ď41, and actually went to Cambridge, early in September of Ď41 and joined the Radiation Lab there.
Weart:They talked to you about it on trips back, or by letters?
Babcock:Mostly by letters. There wasnít very much traveling.
Weart:Do you still have some of these letters, by the way?
Babcock:I arranged with Struve to take an indefinite leave of absence, I went to the Radiation Lab, Iíd gotten married by this time, so I took my wife with me, Actually, the Lab was under tight security, I knew in general terms what they were working on, The security was surprisingly tight in those days, and I was given to feel, when I went back there and started to get acquainted, that I really shouldnít be asking questions. I was given a very thorough interview by some FBI interviewers. Questioners went to my parentsí house here in Altadena and asked my mother about me, disturbed her tremendously. ďWhy are they asking all these questions?Ē
Weart:Did you know that they were doing radar when you went there?
Babcock:I think I knew about that much, But ďelectronicsĒ was probably the significant word, Anyhow, after I got there it was clear that if Iíd had a stronger background in electronics, it would be good, but I could learn something in a certain division which I was put into, This was under Bob Bacher, It was my first acquaintance with Bacher, I met Lee Dubridge, who directed the Lab, And then we had weekly meetings back there, so I began to learn what it was all about, and to make the acquaintance of some of the physicists around the place, It certainly was a very interesting thing. We had talks from British pilots, people who were using radar in the battle of London and all this kind of thing, so it was a fascinating experience, But after a couple of years, or maybe a little less than that, it was clear to me that what I was doing was kind of routine, and not likely to be directly applicable to military operations, I felt that staving there wouldnít really be very productive.
Weart:What kind of work were you doing?
Babcock:I was in the indicator group, and we were concerned largely with developing cathode ray circuitry to present airborne radar information for pilots of aircraft, So we worked on plan position indicator circuits, and range circuits, and indicators to convey an idea of the range of a target and position of a target.
Weart:So none of this really used anything that you had.
Babcock:It was mostly new to me.
Weart:Where did you learn electronics?
Babcock:I picked up most of it there, although I had played with radio transmitters and receivers; I had also revamped some of the coronaviser circuits. The pressure was on, and one simply had to pick it up by osmosis, or some reading on the side, or whatever. It was not useless, by any means, I developed two or three ideas that were patented, and one or two of them were even followed up later. We had some interesting tests, too. Some of these phototype systems that we built were installed in B-18ís and we flew around with them at night over the coast of New England, tracking tame targets. It was kind of wild and hairy in spots.
Weart:How did you feel about doing something so different from astronomy, with very immediate, practical applications, and so on?
Babcock:Well, it was all right. It was the thing to do. In times like that, u couldnít pursue astronomy on a lone mountaintop. There was a war on, and technically minded people ought to be doing something productive to help along with the war effort. Thatís the way everybody looked at it. Here at Mt. Wilson, the amount of astronomy being done went down. There was a great limit on that. And most of the more technically minded people were doing war work. The observatory shop was doing war work, and the staff members were too, The same sort of diversion had occurred during WW I (l9l7-l9l8) when, for example, my father worked on early sonar for submarine detection.
Weart:Did you see this as a temporary diversion from your real interests?
Babcock:Sure, There was the thought, I suppose, that as soon as the war was over, one should get back into astronomy. But in the meantime, war work was obvious. This was just another resurgence of the same thing that happened in World War I.
Weart:So then, you say you began to feel that what you were doing was not that important or that immediate. Did this have to do with your move back here?
Babcock:This had to do with my move back here, I was aware that at Cal Tech, there was a different war project. It was concerned with rockets.
Weart:You heard this through your father, I suppose, or friends?
Babcock:There again, I think that Gerry Kron, my close associate, came out here first; there were other astronomers here. Elvey came from Texas to Pasadena. I think I wrote to Gerry Kron and asked him how he sized up the opportunities, and whether it would be better for me to come back to Pasadena, However, I did make the decision to come back, Frankly, part of it was the selfish reason that I wanted to be in the Pasadena area. My parents were here, they were not in too good health and I was concerned about them, And, well I knew so many people around here it just seemed the thing to do, Again, Cal Tech had a new war project, a new war laboratory just getting started, with every evidence that it was going to grow. And this did happen. So I came back and got into it. There were various groups. I worked pretty closely with Willie Fowler for a while, and Carl Anderson, and Charlie Lauritsen. There was a lot of interesting activity. It was pretty much hardware, hammer and tongs stuff, nothing very sophisticated about the early phases of it. We devised rockets and launches and we took them out in the desert and shot them off to test them.
Weart:What specifically was your job? Or was it more general, everybody works on everything?
Babcock:For the first year or two, my work was mostly connected with aircraft rocket launchers. That is, devices and mechanisms for permitting the firing of ordnance rockets from aircraft. I worked in association with Carl Anderson and with some engineers over at Douglas Aircraft Company. We made frequent trips over to Santa Monica to work with the Douglas Aircraft people. Then we had airplanes equipped with experimental devices and weíd have these taken out to Goldstone dry lake, where we conducted test firing. At the same time we developed new types of rockets, and assisted in their ground testing and in their firing from aircraft.
Weart:This is sort of mechanical engineering kind of work, what you were doing, or electronics?
Babcock:Initially supplied physics and mechanical engineering. Later I worked on electronic sights. Mostly pretty crude stuff, There were some ballistics involved, Bowen, incidentally, was in charge of the photographic unit that made all the photographic records of the testing.
Weart:Were there other astronomers involved?
Babcock:The other astronomers included Elvey, Titus, Kron, and O.C. Wilson, I donít recall the names of any others right now, but there were of course many physicists, some Iíd known before and many others I got acquainted with there. Then, after we got some of these rockets developed to an operation state, there was a good deal of training required. We had to equip squadrons of aircraft for the Navy and the Marines, and then see that the pilots were trained. Then we had to learn how to aim these confounded rockets, The early models were notoriously inaccurate anyway. But the forward firing ones were a real weapon. Their value was recognized, and they were widely installed on operational aircraft, Millions of rockets were made by our production division. I got interested in the business of devising sights for use by the pilots in aiming these rockets. So with a small group there, I did develop an automatic sight for firing at surface targets.
Weart:Here, let me switch this now.
Babcock:We tested these sights, at Goldstone and later at Inyokern, (China Lake). The Navy was sufficiently interested to request us to build quite a number, which we did, We got into a small, sort of prototype production effort, and we built these things and saw that they were tested. Some of the sights actually got into use before the end of the war. But shortly after that, the war came to a conclusion. In the last year of the war (1945) I had the opportunity of going with Carl Anderson to Los Alamos, where we talked to many of the physicists working on the Bomb. I had the great good fortune to be in one of the important meetings there, when there was planning being done for the first military use of the atomic bomb.
Weart:How did that come about, that you were in on one of these meetings?
Babcock:It came about more or less in this way, that here at Cal Tech we had rockets, we had test ranges, aircraft groups, firing procedures and sights, And the atomic bomb was being brought along by the people at Los Alamos to the extent that they had to think about how to deliver it, And so at a hight level, I guess, there was a plan to co-opt part of the group at Cal Tech to develop airdrop equipment and techniques for testing the bomb.
Weart:That would be about Ď44, then?
Babcock:This was early 1945, In fact, it was in January of Ď45 that I went over there with Carl Anderson, Anyway, the meeting was a very interesting one, It included people like Oppenheimer, Captain Parsons and a dozen others, Iím not sure whether Teller was around but he might well have been. It was quite a gathering, But all this didnít result in any significant activity, as far as I was concerned. There was a lot of talk about how important it was to develop this or that, telemetry and whatever, but the organization, the direction, never came through from the top. And little ever happened as far as we at Cal Tech were concerned, really, I remember being introduced to Niels Bohr, although he was not in the meetings After the meeting Oppenheimer took me aside and asked me to develop radio-telemetry for testing bomb drops from B-29 airplanes, right away, I felt flattered but inadequate.
Weart:Was this the first time that you learned that atomic bombs actually could be built?
Babcock:No, Back in the earlier days at the Radiation Lab, it was clear that some such effort was getting started, Bacher kind of sounded me out once, trying to determine how much I knew or suspected about it, In fact, some people from the Radiation Lab were detached and sent over to a place called Y in those days, to get things started.
Weart:I see, So you sort of knew what was going on, had some vague idea.
Babcock:Yes, There was some talk about it. And of course going over there with Carl, and being invited into this high level planning meeting that was a real experience.
Weart:That must have made quite an impression on you, to see what was likely to happen.
Weart:What were your feelings when you first heard about Hiroshima?
Babcock:Well, even before that I had developed my own feelings about it, I mean, as a result of being in on this planning meeting. It seemed to me that here they had this new weapon about ready to go, and I thought that what they should do is make some demonstration of it, but without using it against any civilian targets.
Weart:Where did you come on this idea? This idea was being talked about at Chicago, I know.
Babcock:I think it was just my own idea, It was obvious that plans were being made to deliver this bomb from an airplane. The target I think was not specified, and maybe it wasnít even clear whether it would be a military target, a demonstration, or a civilian target. But I had my own feeling that the first use of this thing should not be against any civilian targets. I think I had the notion that some really powerful demonstration of this thing might convince the Japanese that they should surrender.
Weart:Thatís very interesting, that you came up with this without having heard the people at Chicago, You didnít know that people at Chicago were pressing the same thing?
No, I think anybody, any scientist who was aware of the possibilities would see, hereís a spectrum of choices that have to be made, and what sort of choice should it be. I guess maybe I did have an inkling that the decision might not be to give a mere demonstration. I really think that in the first half of 1945, I could have gotten more involved in testing, telemetry, that might have had something to do with helping along this bomb thing.
Even though there was no particular organization from the top that sort of cancelled it out anyway but I felt disinclined really to get much involved, because it wasnít clear to me how the bomb would be used and I had some reservations about it, I just felt, well, thereís no particular reason for me to get over onto that project, The decisions are being made anyway and why should I get involved? And I donít particularly like it, if theyíre going to drop this thing on a city.
Weart:I see, So when you heard the news of Hiroshima?
Babcock:I think I was halfway ready to expect that this was going to happen. I wasnít particularly surprised about it. In fact, I had heard before that, on the grapevine, about the Trinity Test on the desert. So I had a pretty good hunch they were going to detonate one of these things over or near Japan. So I wasnít surprised.
Weart:I see, Oh, one other question about the war, Right after the war, you wrote a paper on an electronic code translate, Did that have any relation to your war work or was that something else?
Babcock:That was just a separate little avocation that I worked on in the evenings, While I was on the rocket project at Cal Tech, for quite a while I wasnít doing any electronics, But I was thinking, I was inclined to think about applications of electronics, Somehow I got onto this code translator, and I worked it out and published a little paper on it. It was in fact, a digital computer; I independently invented the binary code for it.
Weart:I see. Itís very clever, actually. But that wasnít an assignment?
Babcock:No, that wasnít an assignment. I just did it in spare hours in the evening.
Weart:Letís see, anything else about the Radiation Lab, or about the rocket project, anything else I should be asking about it?
Babcock:Well, just in general terms. I acquired some general knowledge of solid fuel rockets, and what itís like to experiment with them, and an appreciation of their inherent inaccuracy. While I had no contract with liquid fuel rockets, I was impressed with the tremendous amount of effort and experimentation and money that it would take to develop rockets to be useful, letís say, as scientific probes.
Weart:You had thought about it at this time?
Babcock:There was a general awareness, And there were people like Frank Molina and others talking about it, I was perhaps more aware than some astronomers of the very great development efforts that would have to be made to achieve usefulness, and I wasnít too much inclined to devote my life to that kind of activity.
Weart:I see, In terms of a carryover into postwar things, it was more a feeling that there were better ways to do astronomy than with that kind of thing?
Weart:I understand. Any other carryovers from what you learned during the war, what you saw during the war, to the way that you did your research after the war?
Babcock:For myself personally, I picked up some expertise with electronics and of course I could apply some of this in astronomy, but that was just an offshoot. After the war was over, the big question was, well, fellows, how do we get back into astronomy? Whatís going to happen? Obviously the 200-inch isnít quite finished yet. That will have to be brought along. Presumably, astronomers who have been on war lab work are going to get back to observatories, Of course, I was wondering what my chances were.
Weart:Was there a feeling that astronomy would sort of be picked up at the point where it left off before the war in terms of the scientific ideas and in terms of the organization?
Oh, I suppose in terms of organization, yes, Here, people around the observatory were well aware that the Carnegie Institution was headed by Vannevar Bush, who also headed the nationís scientific war effort essentially he was head of the OSRD and had done so much of the planning and all that. It was clear that as president of the Carnegie Institution. Bush was now going to be able to turn back to peacetime science.
And everyone felt, well, the observatory will pick up again, and perhaps have some new possibilities now. Of course, I was just a fellow in a war laboratory that was breaking up. I was wondering, of course, what Iíd be doing. I wanted a chance to stay here and get back into astronomy. I had a couple of offers to get into the aerospace industry, or to go to a Naval lab and have some responsibilities for weapons development. But quite frankly, I turned down the most significant offers just on general principles. I said, no, I want to get back into science, So I burned a couple of bridges there.
Weart:You didnít want to work for industrial or military organizations?
Babcock:I didnít really want to, I was set on doing research in astronomy. So I was going to hold out for whatever might turn up.
Weart:I see, You could have gone back to Yerkes?
Babcock:Oh, it might have been a possibility, but it didnít enter heavily into my thinking at that time.
Weart:I see, So then?
Babcock:I was walking along the campus one day, and Ike Bowen came up and offered me a job at Mt. Wilson, He was taking up the directorship on January 1st, 1946. Iíd known him on the rocket project, and he knew of my back ground and some of my interests; fortunately for me, he offered me this job.
Weart:I see. How did you know him on the rocket research? What was the connection?
Babcock:Since he was a senior member of the group and in charge of all the photographic assessment of the test firing, and for a while I was concerned with actual tests on the ground and from airplanes, I naturally worked with him, We worked in coordination to set up many tests, and so forth.
Weart:To backtrack a bit, I forgot to ask you about your wife, What was her background? How did you meet? What was her educational background?
Babcock:I met her while I was at Yerkes. Her background was rather different from mine; she was of Norwegian ancestry, And she had no interest in science. She was a high school teacher-in Lake Geneva Wisconsin, We were married in 1940, and went to Texas to live at McDonald Observatory for about a year before moving to Cambridge. She was my first wife, and that marriage ended in divorce quite some time later.
Weart:I wonder, could you comment on whether the fact that youíve been an astronomer, and the life of an astronomer has that had any effect on your married life, positive or negative?
Babcock:I think that being a professional scientist can be very demanding. It didnít leave me very much time for social activities, and probably my social life was far more limited than for other people that I knew who were not in science, But as far as the routine in connection with an observatory is concerned. I donít think it mattered much. A few nights per month of observing on the mountain didnít seriously disrupt the domestic scene.
Weart:More a matter of the intensity of the work, I suppose. This is what other people have told me.
Babcock:Yes, I think thatís important.
Weart:Now, tell me your initial impressions when you came back to Santa Barbara Street, How did things get started up again after the war? You were right from the start while things were getting back how did that work?
Babcock:It was a transition period, because Adams had stayed on as acting director past his normal retirement until the end of Ď45 and then Bowen had his new appointment coming as director in Ď46, And not only that, but Bowen had heavy responsibilities to complete the 200-inch, and furthermore, to organize the joint operation of Mt. Wilson and Palomar between Carnegie and Cal Tech. So Bowen had a tremendous task, really, ahead of him there, to set this up, He took quite a firm line in developing policies. One disadvantage for him was that being a physicist, he wasnít very widely acquainted with astronomers and some of their national and international organizations.
Weart:The larger community.
Babcock:He had been up at Lick Observatory, Heíd been a Morrison fellow, and he knew the people at Lick, But he wasnít very widely acquainted in astronomy, or with the American Astronomical Society or with the I.A.U.
Weart:How did people feel about that? Do you know how or why Bowen was picked to be director here? I4ow people felt about the choice?
Babcock:I donít know too much about it I know that there were t people here who probably were disappointed that they didnít get the job, One of them, I think, was Merrill, and the other was Ted Dunham.
Babcock:How Hubble felt, I donít know, It was pretty hard to tell, Anyhow, Bowen consulted him and as far as I could tell he and Bowen got along as well as Adams and Hubble had got along.
Weart:I guess for people like Merrill and Dunham, it would have been difficult seeing a non-astronomer, somebody from Cal- Tech, rather than from the observatories.
Perhaps so, Yet everybody was well aware that Bowon was highly qualified in optics, he really knew the score on that, And as a spectroscopist also he had made first-rank contributions in astrophysics, the puzzle of the nebulium lines and so forth, and his work on spectra of planetary nebulae, And the fact that he was a physicist, Bowen had been deeply engaged for years in the design of the 200-inch telescope, Van Bush, I think felt very strongly that Bowen was the logical choice, I think most people accepted this quite readily. Anyway, Bowen was intent on getting things started, And I was fortunate in that he offered me a job here, At the same time, people came back or dropped the war work that theyíd been doing.
This did include for a while Dunham and Wilson (Olin Wilson is another of the astronomers who was on the rocket project here). So the observatory began to get back to more normal kind of activity, but also with the new growth plans in the forefront. Among the items that Bowen wanted was a new direct intensity micro-photometer, which he felt was very essential. His idea was, the observatory ought to get heavily into the field of stellar abundances, the abundances of elements in stars and galaxies, He was ready to give a lot of hacking to instrumentation or whatever it took to make real progress here. The importance of nuclear reactions was now being appreciated, and how the sun generates its energy, and it was regarded as very essential to work on abundances so we could tell what nuclear reactions were going ahead in stars.
Weart:I see, Thatís interesting, Did that have any connection with things that were going on at Cal Tech? Willy Fowler, Jesse Greenstein and so forth?
Babcock:Well, yes— although Iím still talking about 1946ó
Weart:Right, Iím interested becauseó
Babcock:The work on nuclear astrophysics at Cal Tech came later, Iím sure that Willy Fowlerís interest was augmented and stimulated, and certainly it developed over the years into a very important thing, with his lab down there—
Weart:But Bowen had this interest even before all that began?
Babcock:Oh yes It s Bowen who brought Jesse Greenstein here, about 1949, I believeó
Weart:Ď48. Yes, and Greenstein was already sort of interested in abundances.
Babcock:Jesse was already interested. I think thatís one reason why Bowen wanted him here, and he promoted Jesseís work in the abundance field. It seemed pretty natural. There was a great deal to be found out by analyzing stellar spectra, and doing a wholesale job.
Weart:I noticed in your work on magnetic stars, you mentioned in one of your papers that this had some implications for abundances.
Babcock:Well, yes. There are some very peculiar abundance situations in magnetic stars.
Weart:So again this partly came from Bowenís impetus? Weíll get back to that.
The answer is ďNoĒ, but we might get back to that, Anyway, Bowen realized that there was a lot to be done on abundances, and one of things he wanted was to develop the coude spectrograph on the 100-inch, and later on the 200-inch, so that it would be possible to get good high-dispersion spectrograms of stars, well calibrated, And then he wanted a first class analyzing instrument here, a direct-intensity microphotometer. He gave me the assignment of designing and building this microphotometer. It worked on a principle developed earlier by Williams and Hiltner at Michigan, OK, this was an assignment and I had to do it, and I had no electronic assistant, nobody to wire connections or anything.
So I put this thing together, I designed the electronics, I built it myself, bought every transformer, every vacuum tube socket, and I did the whole thing. It took half my time for two years, which was a big drain, At the same time, with Nichols, our engineer designer over here, we designed the rather sophisticated and elaborate mechanical parts of this machine. The machine was built in our machine shop, at very considerable expense, I hooked it up and got it working in 1948, down here in the basement. And I ran through some plates. I built a calibration spectograph so we could make the wedge calibration plates, and I got it to the point where it ran off direct intensity tracings.
Now, this would have been the logical thing, according to Bowenís plans, for people like Greenstein and others to use. The machine was finished, and it has sat there ever since, I donít think one serious abundance spectrogram was ever run through on the thing. At least nobody ever used it in a systematic way.
Babcock:Itís a little hard for me to answer that, I think it could have been quite useful, But people were already into the somewhat more, well, somewhat less sophisticated thing of doing microphotometry by making density tracings. Again, with a suitable sort of calibration plate, And then they made microdensitometers that had a logarithmic response, in order to take out the curve of the plate.
Weart:Right, they had this very elaborate means for getting past reciprocity failure and so forth.
Babcock:Yes, In any event, the machine was possibly too elaborate, It may have turned off people who didnít want to bother learning how to use it, I still think Bowens idea was OK, and I donít begrudge a bit having put in the time, It was educational, But I have to remark that the time was wasted.
Weart:It was done essentially at his direction, I noticed in the directorís report it said Babcock has been hired letís see if I have the quote here ďBabcock joined the staff on January 1st, 1946. His chief interest will be in stellar spectroscopy and the development of instruments using electronic techniques,Ē So was this sort of understood before you came, that you were hired to spend half your time or whatever on building instruments?
Weart:So you knew before you had even arrived, that that was to be your job.
That was to be an essential part of my job, On the other hand, I had at least half my time to do research, and I hadnít yet told Bowen what kind of research I wanted to do. Anyway, in January of Ď46, here I was, a new member of the staff of Mt. Wilson Observatory, I had a chance to choose some research project, something to do, I had no commitments really, as far as astronomical research went, and I felt, Iíd better come up with something pretty good to justify this opportunity, I remember, I specifically went out on the front porch and sat down one evening and said to myself, ďIíd better come up with something here, What am I going to do in research?Ē
I got to thinking about fundamentals what do you learn from radiation that comes in from celestial objects and it seemed to me that polarization as a quality of stellar radiation had been neglected almost completely, And that if you looked at fundamentals, you could measure frequency or wave length, you could measure intensity and position, and people had been doing all those things, but they hadnít done much on polarization. That was one of the ideas. Just how I got onto thinking about magnetic fields of stars— I suppose it goes back to all of the long-standing interest in the sunís general magnetic field that had been around here, and which Hale had devoted so much effort to. But somewhat I got to thinking, suppose you had a star with a far stronger general field than the sun, not just one gauss but thousands of gauss, Would there be any chance of detecting it?
At first thought youíd say, well, probably not, because you have to integrate over the whole surface (of the star) and it would pretty much average out, But I got interested enough to really look at it, and take account of possible distributions of the flux over the surface, the dipole field and limb darkening. I integrated the thing out, and concluded that there would be a chance of detecting it if the polar fields were three or four thousand gauss or more. It further occurred to me that such strong magnetic fields might be generated by dynamo (circulation) processes, or otherwise, in rapidly rotating stars. From Struveís work it was known that most early type stars rotate far more rapidly than the sun. One could utilize the longitudinal Zeeman effect, which makes use of the polarization, and it wouldnít be very hard to make a suitable analyzer. So I sketched an analyzer and I went in and talked to Bowen about it, He said, ďOK, why donít you give it a try? Iíll give you a couple of nights on the 100-inch in April.Ē
Weart:Itís interesting that nobody had ever put an analyzer on the 100-inch before, I find a little hard to understand, almost.
Certainly not an analyzer of that kind. Many years earlier somebody up at Lick, I think it was Wright, had the idea that for certain emission line stars, in some of the bright lines like bright hydrogen lines, there might be polarization. And Merrill or somebody had used a very elementary polarizer down here, and maybe taken a couple of plates, I donít know anyhow he didnít find anything. This was just on the hunch that emission lines might be polarized. Anyhow, I got a little calcite crystal and a piece of mica and made my first analyzer.
As a matter of fact, Merrill didnít quite think it was suitable to just outright assign a young staff member a night on the 100-inch to himself; he might be wasting the time, So he said, ďLet Sanford take a plate for you,Ē OK, I gave Sanford the analyzer, and he took it up on one of his runs and he took a plate of some star. Well, it looked all right, in the sense that the analyzer worked. It produced two parallel spectra, And that was enough to convince Merrill, who I think was doing the scheduling, that maybe I could have a couple of nights, So I went up and got some spectra of 78 Virginis and later a few other stars.
Weart:78 Virginis was one of the first stars you looked at?
Babcock:Yes, It was the first one I measured up in detail, where there was real evidence for a magnetic field, yes.
Weart:I see. Thatís interesting. It must have been quite exciting when you found that there was a magnetic field there.
Babcock:That was pretty exciting, But I must admit that the signal to noise ratio was not as good as one would like, I was convinced the effect was real, and so I immediately began checking out a number of other stars. What really excited me was (I think this was two or three months later) I got some plates of MD l25248 which had a much stronger field. The field was so strong that the line offsets were right there; you couldnít doubt them.
Weart:Were you looking at these with the naked eye? Did u see it immediately?
Babcock:You take a hand lens and look at them. You could see that the europium lines, chromium lines, and others had big offsets.
Weart:On the plate?
Babcock:On the plate, yes, You just look at the spectrogram with a hand lens, You could see the europium lines were offset and there were a lot of other lines offset too, This star had a strong field, and I measured it up. A few days later I went up the mountain and got another plate of the same star. It was known to be a spectrum variable with strong lines of europium and chromium, Well, this time chromium was strong while europium had gone weak, I got a spectrum, and it showed these big offsets. And I was tremendously excited, because I was sure that they were in the opposite direction from the first plate, That is, the magnetic field was of opposite polarity. But the first plate was down here in my office, and I was on the mountain, I talked to Olin Wilson about it and told him I was practically certain that the magnetic field was now showing opposite polarity.
Weart:You phoned him up?
Babcock:No, he was on the mountain observing the 6O-inch. Thatís what really got me excited, Here was a field, not only very strong, but it reversed polarity. And it was in a star showing very strange apparent abundances, line strengths anyhow, and it was a spectrum variable. So after that I had no trouble in getting quite a lot of observing time.
Weart:I see. At the beginning, you were simply interested to see whether you could find magnetic fields, but then almost immediately from the data you began to see that there were all these other possibilities?
Babcock:Yes, it soon became clear that if one picked out these sharp line A.type stars many of those were in fact known as peculiar stars or spectrum variables, and there were no two of them quite alike it was well worth checking them out to see what the magnetic phenomena were.
Weart:In one of your papers you wrote, ďItís possible that the key is at hand to some of the peculiar phenomena of stellar spectraĒ which was in fact the case. This was sort of the motive for what you were doing?
Weart:Now you had the ability to understand a class of things that hadnít been understood before, Certain types of variables andó
Babcock:Yes, it was clear that here was more very interesting physics that would have to be looked into, and that we were very short of observations, that more observational data were badly needed. Of course I felt somewhat of a lack, in that I wished that I had a better background in theoretical spectroscopy, in line formation and in all the physics that backs up these items. I had a less extensive background there than would have been desirable. Nevertheless, there was so much to be done that I felt it was no real problem. I could go ahead on these observations, and there would be plenty of people around to take part in the interpretation. There was a lot of research waiting to be done.
Weart:Iím interested also whether, in your first year or so, a part may have been played by this idea that Blackett revived, (in 1946), that there was some connection between rapid rotation of a large body and electromagnetism.
Well, before I ever heard of Blackett, I was interested in this basic problem. In the sun we have, probably, a general magnetic field in a star that is a slow rotator. And as I think I made clear in some of those early papers of mine, I did tend to associate the idea of strong fields with fields with rapid rotation, I was very definitely trying to select stars that had sharp lines, which could be seen pole-on, but there was reason to think maybe they were rotating very rapidly. A very small proportion of the A-type stars would be of this type, nearly pole-on.
I really did have the notion that the rapid rotation would somehow result in strong magnetic fields, Possibilities would include internal circulation that might be somehow stirred up and augmented by the rapid rotation, or, God knows, maybe some fundamental thing. Then Blackett came out with his idea, He was rather provoked that it took me so long to come out with my first publication on the subject, But getting things published around here in those days was a pretty lengthy process. We had a very strict editorial review internally.
Weart:I wanted to ask you about that.
Babcock:This really was pretty awful, as I look back on it, It was very much of a hindrance. It was perhaps the better part of a year before this paper on 78 Virginis came out, I remember Blackettís paper later that said that ďBabcockís work on 78 Virginis has at last been published.Ē
Weart:He knew that you had been working on it? You had corresponded, or
Babcock:There might have been some brief note in the PASP or some other—
Weart:I see, directorís Report or something.
Babcock:I donít know now how that came about. Years later, in Stockholm, Blackett and I met and had some interesting talks.
Weart:Did your father play any role in this? He showed an interest in your work, certainly.
Babcock:Yes, he was interested in it, and when I had to make an analyzer, he assisted me, in showing me how one could select the mica, make a quarter wave plate and mount it properly, This had in fact been done earlier here by Ellerman, who made analyzers for Hale to use on sunspots, So the tech nique of splitting mica and testing it was known, and my father showed me some of that technique. But beyond that, he just had a strong interest in what I was doing.
Weart:To get back to what you said a little earlier, how you felt you could do the observations and there were plenty of people who were interested in analyzing it yet I was interested that you did in fact do some theory about the formation of the lines. You applied Schwarzschildís oscillating model and so forth. Did you feel that it was part of your job to do this theory, or was this something extra you did simply because you were interested in the problem?
Babcock:Oh, I was interested in it, I felt that my first responsibility was to proceed with the observations, make the best choices I could as to significant stars to observe, to find out the maximum amount of physics with a given amount of work; and then to try to interpret the things to see what was going on. But before long a number of other people, like Stibbs and Deutsch and so on, got interested. I soon began to feel that there wasnít time enough to do everything on this subject that I wanted to do, but at least that I would continue with a pretty heavy observing program on it.
Weart:Was there much encouragement to restrict oneself to observation, or was there encouragement to do theory? Was there any general feeling around here about that kind of thing?
Babcock:No, no very strongly stated policy, It was clear that we had the only observational equipment really suited for this kind of work, Iím talking about 1946, And because it was obviously significant, Minkowski and Bowen and others were quite interested in it, It was the thing to do to push ahead with it, and I had no trouble getting quite a lot of observing time, When the reversing field of HD 125248 came along, I think it was Bowen who suggested I should take eight nights in a row on the 100-inch, and get it on every night throughout its nine day period. So he strongly supported me.
Weart:I see. He managed to fit you in quite rapidly?
Babcock:Yes. As I say, I was given generous allocations of observing time.
Weart:I see, So then, as you said, this developed into a long range project. In 1953, you had 1100 spectrograms of dozens of stars, By 1958 you had a catalog, a general classification of the Ap stars, Iím wondering how you felt about doing such a long-term study?
Babcock:I didnít mind it, because from time to time very significant things would turn up. You see, in these years the 200-inch with its coude spectrograph had come into operation, so I was able to do additional things there, Sometime in the middle fifties, this star with a very strong field turned up - HD 215441, It had a 34 kilogauss field,
Babcock:This was so intense that it was quite an eye-opener, and I was tremendously interested in that one. At the same time, while this work on magnetic stars was my first concern, I felt that perhaps useful ideas about the interpretation of the stellar fields might come from doing further work on the sun, and finding out about the sunís general magnetic field, Does it have one, and if so, what are its properties?
Weart:Letís get back to that - I certainly want to ask you about that, but first I have some other questions about the magnetic stars, In the first place, this long program period was supported by people here? People felt good about supporting this kind of a very long, large-scale study?
Weart:You thought it was important for things like stellar evolution, or solar system cosmogony, that sort of thing? What were the larger scale things you thought this would be contributing to?
There was also the question of the origin of stellar magnetic fields. Were they primeval, concentrated from the interstellar medium when the star was formed, were they generated internally by some dynamo process, or were they perhaps fundamentally the result of rotation? It was clear that strong fields were found in these peculiar stars that had very anomalous surface abundances. And it was a very interesting problem in physics to determine what was going on. Did these magnetic stars have peculiar nuclear reactions going on in the interior, perhaps because they had magnetic fields, and did this result in the abnormal abundances? See ďThe 34-Kilogauss Magnetic field of HD 215441,Ē Ap. J. 132 (1960), 521ó31. Or was there some effect on the mixing, some effect of the magnetic field that led to a concentration of some elements on the surface? Or were there perhaps energetic reactions occuring in the stellar atmospheres, due to changes in the fields, acceleration of ions and what not, resulting in nucleogenesis in the starís atmosphere? Or could it be some selective infall of interstellar stuff to the surface of the star, guided or influenced by the magnetic field?
One would like to find answers to some of these questions. Therefore, some survey of all types of stars that might show fields was indicated, This included some white dwarfs, and this was partly in line with some of Blackettís ideas, And I did take spectra of one or two white dwarfs, finding no evidence of any strong field, Also, it became clear that some of the phenomena that could be observed were really quite complex, If you take spectrograms, with the analyzer, of some of these brighter spectrum variables, you find that not only do different elements show peculiar magnetic field effects, but they may show peculiar velocities, The chromium may have a different velocity from the other elements at some phase in the variation.
The line profiles may show subtle peculiarities that need analyzing, There was the so called crossover effect, asymmetries in the profiles and so on, There was a lot here that could be sorted out, and if one made sense of it maybe he could get some leverage on the interpretation. I tried to keep an open mind here on the interpretation. Of course, the oblique rotator theory was in the foreground, and also there was the notation that maybe thereís some kind of magnetic oscillation that could go on, One ought to learn what could be found out, to make a choice here.
I did make quite an effort to make systematic observations of a selected number of stars, to determine how many of them were periodic, and how many might be irregular and so on. As it turned out, you know, many of those that I thought might well be irregular have since been proven to be periodic. And it may be that there is no truly irregular magnetic variable.
Weart:Oh, is that so?
Babcock:But thereís argument in the literature on that right now, Many of them are indeed very regular. But some of them had abnormally long cycles or periods. I became fascinated by some of those. There was one with a period of 220 days, and some turned up with even much longer periods than that, I got to feeling rather doubtful that a star could get slowed dowa, braked, by magnetic effects to such a tremendously long period as, say, five years. But the long period changes nevertheless are there, I still feel that the subject needs more attention, but itís not getting much right now.
Weart:Tell me, a little bit to the side the measurements were made by a Miss Sylvia Burd and Mrs. A.J. Deutsch, Who were these people? What did they do?
Babcock:Well, Sylvia Burd was employed here for years as a research assistant, and when I got into this kind of spectroscopy, Bowen let me call on her for about half of her time. She would actually measure my plates.
Weart:I see, she was employed by the observatories and he simply assigned you her time?
Weart:She sat in her room somewhere and measured plates.
Babcock:Yes, she had a little room here down the corridor. She was great at it. It must have been a terribly dull kind of activity.
Weart:But she didnít complain?
Babcock:Well, that was a job. We tried not to load any one individual fulltime on such work, but it still must have been very monotonous, But she was extremely good at it, very painstaking, very careful. Then, after Deutsch joined the staff his wife was in these parts, and she had I think a part time job of a similar nature, and so she did some measuring for me as well.
Weart:I see, the same kind of thing.
Babcock:Same kind of thing, yes.
Weart:OK. Another thing I should ask you about, and this goes back to the late forties and early fifties, is about ruling the gratings. Itís very interesting.
Yes, that was an important activity here at the observatories. It was initiated by Hale way back around 1915. At that time he brought out John A. Anderson from Johns Hopkins to assist in the design of this large ruling machine that Hale wanted built, and Hale brought Clement Jacomini, a very talented instrument maker from Italy, at least he had a great reputation. And there was F.G. Pease here, a skilled mechanical engineer. So they designed this very large machine capable of ruling gratings 20 by 24 inches.
It was built by Jacomini, and operated, but never very successfully, up till 1928 or so. Then they decided theyíd set their sights too high, and a smaller machine was designed by my father, H.D. Babcock, with Edgar Nichols, Elmer Prall was instrument maker. My father took charge of the activity and worked with Prall through the thirties and up to 1948. When my father retired in 1949, Bowen asked me to take over the diffraction grating project.
Weart:Why you, rather than somebody else?
Babcock:Because I was acquainted with it and willing to give time to it, I had been looking in on it for years, Dunham I think had left or was leaving at about that time, and I guess Bowen thought I was the logical one. Anyway, I was willing to do it, even though I realized it would be a very time consuming activity and would have to go on for many years. It still could contribute a lot to spectroscopy, And we had Prall, a very skilled instrument maker who had built this new machine, So I took it on. The first assignment was to make one or two improved or new gratings for the Mt. Wilson coude, and then to make a matched set of nearly identical gratings for the Palomar coude.
Weart:Where did this idea come from, of this mosaic (of four gratings)?
Babcock:That was Bowenís idea, because he realized it was quite impossible to rule a single grating of 12X15 inches, which was needed. Itís still needed, Bowen devised the idea of the composite, and furthermore he devised the mounting arrangement which permits fine adjustments of the 4 components to make them work essentially as one (at least as far as intensity goes, not resolving power), So with cooperation from the optical shop (Don) Hendrix over there made these rectangular blanks, and this was a very demanding job, to make them flat and so on.
Weart:And rectangular flats.
Babcock:Yes, rectangular flats, He made the blanks, and Prall and I brought along the machine and techniques do the ruling, By 1950 we had the four gratings for the composite at Palomar. I guess we must have got started a little before í49.
Weart:The record says you took over from your father in í48.
Babcock:All right, Ď48, At about the same time, or just a little later, I was also trying to make special single gratings for the Mt. Wilson coude, and we did eventually get some very good ones in up there, We replaced a grating made by H.A. Wood that had been there for a long time.
Weart:Did you ever meet Wood, by the way?
Babcock:Oh, yes, Yes.
Weart:What kind of fellow was he? Iím curious because I always hear things about him.
Babcock:Quite an impressive figure. Pretty communicative, talking about his interests and so on, I always liked to hear him talk, He would tell some things about his early program. The thing I remember best is a second hand story from Bowen, who didnít think too much of Wood, I donít know whether I should get into that, Itís only secondhand.
Weart:Go ahead, you tell me, you can cut it out later if you want.
Babcock:Well, Wood was here at Cal Tech and one time he gave a physics seminar. It was mostly an experimental thing, and he brought out his ideas. pragmatic things and results, and he says, ďI donít have time to go into the theory of all this, I wonít burden you with that, I just want to give the basic results here,Ē And somebody spoke up and said ďThe theory would really be significant. Why donít you just take ten minutes and at least sketch out the theory for us?Ē And Wood couldnít do anything. He didnít know anything about that.
Weart:It sounds like him (Laughter).
Weart:By the way, while you were doing the gratings, did you have much contact about the ruling with others, people at the observatories or people outside, or were you pretty much just working there with Prall?
We had occasional contacts with experts like Mr. Kurz from Bausch and Lomb, and John Strong from Johns Hopkins. There were various ruling efforts scattered around here and there, and sometimes these people would drop in, Leibhart had a ruling project, and there were one or two others, But mostly we did it here. We had to go out and get ruling diamonds and consult experts as to how you shape the edge, and all this kind of thing. We had to improve the basic design of ruling engines, and their precision. We had some correspondence with John Strong, who a little later was developing a ruling engine. In the fifties Strong collaborated to some extent.
He wanted for example a coarse grating rule on silver, and he provided the blank coated with silver and sent it out, and we ruled it on our old machine, which was good enough for that particular purpose. So there were occasional interchanges with people like John Strong and Ed Leibhart, Kurz from Bausch and Lomb spent weeks here, as did a designer from Fisher Scientific Company and Ed Leibhart from Chicago. We told them all we knew, and gave them the whole technology freely. We were, in effect, trying to persuade industry to take over the production of gratings to relieve us of the task, I feel that we were responsible for a large share of Bausch and Lombís success in this. The first aim was indeed to make gratings for the instruments here. Mt. Wilson and Palomar, But of course we did have requests from outside, and so we soon got into this activity, making gratings to be sent out on loan or occasionally to be sold at cost. I calculated one time that we sent out a very considerable number (50 to 60) of high-quality gratings, most of them on loan, a few for sale. They went to people like Edlen and Swings; some went to Canada, to Victoria; some went to Oxford and Cambridge; and we ruled some for Lick, two or three quite sizeable jobs for Lick and other observatories. So the number there was quite significant, and the total effort that went into it was large. There was quite a demand.
Weart:What was the interaction with Prall? Iím always interested in the support staff.
Babcock:Prall and I worked pretty well together, and I have a great respect for his skill, He was a craftsman of the old school and had skills, when it came to doing things with metal, that Iíve never seen in any other individual, He had been in our observatory instrument shop since about 1915. He took over the job of actually making the precise screw, for example, the main lead screw for the machine. There was a lot of consultation, and we tried to make the best use of experience and all that, but Prall did the work, and he did it superbly well. He was not fast. He contributed some ideas also to the design of the machine. Basically it was his handicraft, his most remarkable skill with metals, that was indispensable.
Weart:If there was an idea, for example using a new kind of compound for the bearing or that kind of thing, would that come more likely from him or you?
Well, it might have come from either one, Prall was skilled in the hardening, heat treating, and finishing of metals. One that counted was the use of the Graphitar, and that came from Edgar Nichols, who was our chief designer. He picked up a hunk of Graphitar (discarded by the Navy) on the beach, and found out what it was used for; we put it to work and it was ideal, Weíve used it ever since. We were able to make some basic improvements in the kinematics of the ruling machine, I guess I can take some credit for that: going to the monorail diamond carriage where the diamond moves along the axis of the rail, and where the rail is a true round cylinder, a circular cylinder instead of two parallel flat-topped bars. When we went over to using a round bar for the ways, and the monorail diamond carriage, we made some real advances in quality of the gratings.
Then elsewhere of course in the fifties, late fifties, interferometric control was coming in, and Harrison and others had these systems. I felt we couldnít get into duplicating Harrisonís scheme, which was too elaborate, But we developed a simplified scheme for interferometric control which we did put into use, and I think quite successfully; all the later gratings that we made were ruled that way, I felt happy about it. It was relatively simple but effective. So, toward the end of this effort and it wound up as far as I was concerned by 1962 or Ď63 we did make some ten inch wide gratings, some of which have served well in the big tower and the Hale Lab and such places, and one or two we sent out, One of the Lick gratings for the l2O inch was quite sizeable, Iíve forgotten the exact size, but it was a pretty major effort.
Weart:Did you have any special problems in putting together that mosaic for Palomar, other than the problem of getting good rectangular flats?
Babcock:After the flats were provided we ruled these gratings. We had altogether about seven or eight blanks, and we made many trials, trying always to get identical and equally good gratings of good efficiency, high revolving power, and low scattered light. I tested them individually downstairs, and I had photoelectric devices for measuring the blaze and resolving power, I selected the four best and turned them over to Bowen, and Bowen personally installed them in composite holder in the coude. Theyíve been there ever since, theyíve never been disturbed.
Weart:Nobody would dare to touch them, I suppose.
Babcock:Even to take them out would be a tough job. There are thoughts now of replacing them with a big single grating, if such can be obtained.
Weart:I see, Nobody has dreamed of trying to put slightly better gratings in there, It would be a job.
Babcock:Yes, There is an active project now to get some money, and put in new gratings. After all, those in there have been in there for 27 years, and they are getting a bit dull and theyíre not quite as efficient as they used to be. It would be nice to have a large single grating. So there exists now a proposal to get improved gratings, which might be more composites. But nobody knows what the source is going to be.
Weart:I see, And even now if you put in a new one, it might be another mosaic.
Weart:I see, Thatís very interesting, It might be one of the longer lasting gratings.
Babcock:Well, we have some examples a century old, We have an early ruling by Rutherfurd, one by Schneider, one by Grayson (Australia), and a grating on speculum (metal) ruled by Michelson, Itís ďMichelson No. 66.Ē which for many decades was in the big tower in the mountain.
Babcock:Yes, For example, in making the Utrecht Atlas of the solar spectrum.
Weart:Astronomers use things longer than physicists do, Like the old Mt. Wilson telescope — the lOO-inch.
Babcock:Oh, it's going strong. yes.
Weart:And will be for a long time still to come. OK, letís get back to your work on the sun, You built the magnetograph, at the Hale Lab down here in Pasadena. You mentioned the motivations for it came out of the magnetic star work?
Babcock:Well, that was one part of my motivation, The other was that my father had been interested in the problem for a long time. Heíd been rather closely associated with Haleís own efforts to study magnetic fields, and when my father retired, finally, he had the chance to continue to use the Hale Solar Lab down Holaday Road.
Weart:People werenít using it?
Adams shared an office there with Dad. The apparatus was not in use. He wanted to continue this work on the general field (of the sun), and he started by applying the Lummer plate to increase the resolving power of the spectrograph for this particular job. He had some other observational interests there at the same time, I was generally aware, of course, of what he was doing. Along about 1951 Dad would occasionally talk about using photoelectric methods on the sun, but he wasnít very much up on electronics, and so it was rather natural that we would work together on it. I proposed the photoelectric method, using an AC system with a synchronous detector.
This involved first rotating the analyzer, which of course was never awfully attractive, but we couldnít think of anything else. After we got the system working a little with that and this involved some arrangements for scanning we got some results. This was in May, í52. At the time we were using the rotating analyzer. We could scan individual chords across the sun, and we got some interesting results on local magnetic fields. We could record very crude magnetograms on this basis, and it looked interesting enough so that we put in more effort on it, I built a raster scanning device that would automatically cover the whole sun, driving second flat, The greatest improvement was that we threw out the rotating analyzer and introduced the electrically incited birefringent plate of ammonuim dihydrogen phosphate (ADP). This made a tremendous gain. It took out a lot of spurious sources of noise.
Weart:One of the cleverest things, one of those ideas I wish Iíd thought up is just putting a slit on each side of the line, where the slope is steep, looking for that, I always thought that was a surprising thing. I guess itís similar to what one does in a guider, in a way.
Babcock:Yes, I remember that device, We had this slit, and we stretched a piano wire down the middle to make really two slits, and put in a little viewer so we could slip back the prisms and look in to see where the line was, and then go to the recording mode. But the ADP plate was the thing that made a great gain. So then we could begin to measure average fields over some little area, average fields of the order of a gauss or a fraction of a gauss.
Weart:You had planned from the start to be looking for the general field, for the weak field? 12:: i.e. Second mirror of the heliostat.
Babcock:Certainly that was the major aim. But of course, itís also clear that there were a lot of magnetic areas floating around on the sum, apart from the spots, and it was very interesting to track those down, I felt that we came up with some pretty significant results from all that. We didnít make enough of a point of some of them. Maybe a few of them have got rediscovered incidentally, or resurrected or what not. I thought it was very significant that the magnetic areas, after theyíd reached at least a minimum age, always disappeared by expanding. To me, this really was the basis for the idea that the magnetic loops have to break off and float out away from the sun. The concept of continuity requires, then, that there be a ďsolar wind,Ē although we did not introduce the term.
Babcock:You have severing and reconnection, and the magnetic plasma moves away from the sun.
Babcock:Of course, many ideas about the solar wind were beginning to surface about the same time anyway.
Weart:Before you started to come up with all these remarkable things, how did your colleagues feel about this move into solar physics?
Babcock:Oh, I donít know, There wasnít too much comment about it, A far as I was concerned, my main research was on magnetic stars and I got into part-time work on solar physics primarily because I wanted to determine whether the sun had a general field, and if so, whether it varied, Because I was still interested in the notion that there could be some kind of magnetic oscillation, and if it occurred weakly in the sum, maybe it could occur far more strongly in stars, I wanted to check this out. So I always regarded my work on the sun as somewhat secondary.
Weart:I see, So even before you and your father found it, you had in mind the idea that there might be a general field which would reverse?
Babcock:Well, as to whether it would reverse or not, I didnít have any preconceived notions, but I thought there was a good chance there would be a general field there. Hale had the idea, you know, and some people felt that he had some fragmentary evidence. It wasnít convincing, but it ought to be checked out, and photoelectric devices might do it.
Weart:OK, and then you found all these remarkable things — the general field, and the unipolar or dipolar magnetic regions, and how they all changed with time and so on, It must have been very fascinating, seeing all these things.
Babcock:You see, my father and I worked together on it, doing a lot of collaborative observing in the middle fifties, and then I had to pull out, but he continued observing pretty much on his own.
Weart:Why did you pull out, by the way?
There were just too many other demands, I was getting into the business of making up a catalog of A stars, magnetic stars, I was developing a photoelectric AC magnetograph to use on stars at the 200-inch; that took a lot of effort, And there were other things. It seemed best to let my father go ahead with his interests, that is, observing the sun on the longer term, at the Hale Solar Lab. It wasnít quite fair to him, because he wasnít deeply into electronics, his eyesight was failing, he was well into retirement years.
But every day he would go down there and fire up the system and make the tracings and so on. He continued this up through 1961 and he did discover this reversal of the sunís field which was great failed him in not seeing to it that the equipment was always properly calibrated and kept up to the proper level of sensitivity. I think it did get degraded just from lack of attention to some of these items, Iíve always regretted I didnít do better on that. Well, another thing that was in the works at that time was to build a better magnetograph in the 150 foot tower on the mountain.
Weart:Yes, right, you were involved in that also?
Babcock:Yes, I was somewhat involved with that, in fact, I worked pretty heavily with Bob (Howard), especially on the scanning system, display of the results and on improving the sensitivity. We developed schemes for recording and calibrating the results.
Weart:Who decided that that should be done, by the way? How was it decided that the 150-foot tower should be used this way, revived?
Babcock:There were conversations involving Bowen, my father, Bob Howard, and me. Iím sure that Bob Howard was quite interested in it, it seemed, in view of the results from the Hale Lab, that it was the logical thing to do. There were no other strong claims on the big tower, and Bowen was in favor of it. Nicholson was in favor of it, Bob, I think, had the main assignment for bringing along that thing up there.
Weart:Were all these things, by the way, done out of observatory funds, I guess Carnegie funds essentially?
Weart:Including your work down at the Hale Lab and so forth?
Babcock:It was done entirely with Carnegie funds.
Weart:I see. Was there any trouble on getting these funds? Did you have to submit requests, or did it all come along fairly smoothly?
Babcock:It came fairly smoothly, I mean, things like gratings — well, we just worked on it till we got a good grating and we put it in, We could call on (Edgar) Nichols over here, who was an unappreciated designer who did a great deal for astronomical instrumentation. He designed a lot of things, and he helped with a number of these. So things could be built in our shop, and of course Bowen approved them. If it was the obvious thing to do, so there was no problem.
Bowen was pretty generous, when I told him I wanted to build this photoelectric Zeeman analyzer (the spectrum template system) for work on stars at the 200-inch, I think he sank about $25,000 in that system for me. The trouble was that I had too many things going. I didnít have a research assistant for the stellar magnetograph. I needed a good bright graduate student to help along with it, but there wasnít anybody. As for that system on the 200-inch. I brought it along to the point where it operated in the Doppler mode and in the Zeeman mode. It was exceedingly sensitive it used spectrum templates, you know and I showed that one could get very precise radial velocities out of it.
I used it a little bit in the Zeeman mode. One reason I dropped that was, I was completing my catalog of magnetic stars, and in surveying all these rather large numbers of plates, spectrograms of magnetic stars, I was impressed again with the subtle changes in the profiles, the changes of intensity and all these things which meant that you had to have a permanent record, a photo graphic record, if you really wanted to retain the information, Just running the starlight through a template told you nothing about the changes in light intensity or differential velocities of different elements, and there was so much youíd miss that way that I thought I would set aside the photoelectric detector for a while. It was described only briefly (in the Annual Report for 1954-55) and in ďAstronomical TechniquesĒ (Vol. II of Stars and Stellar Systems), University of Chicago Press 1962. I never got to take it up again, though years later, Griffin and Gunn developed their own template spectrometer for radial velocities and used it very successfully at the 200-inch.
Weart:Somebody told me that it was always an idea here that you should, so to speak, take more data than you use yourself, because you have the big telescopes; itís part of your job to accumulate plates and so forth, Is that the sort of thing that youíre talking about?
I donít agree with that idea, and it was not observatory policy, 0n the other hand, weíve always had the policy that, knowing there are many plates in our files, we invite people to come and look at them or send plates out on loan, More specifically. Bowen tried to develop a policy of inviting outside astronomers to come and get their own plates here. He pushed that program, the guest investigator program, very hard for a long time. As a result, we perhaps pursued it a little too strongly in recent years, without adapting to changes in the overall situation.
I refer to the many large telescopes coming into use at the National Centers, which have far higher budgets and which can accommodate many visiting astronomers. We have always had the policy of lending plates to other astronomers, and we have about 20,000 plates out on loan at this moment. We have reached the point where our staff does not have adequate time anymore to properly attend to requests that come in. When people write in and want to borrow plates of this or that for such and such a purpose, it takes time to look into the files, see what we have, get all the related data and so forth. Weíre going to have to make some changes.
Weart:I see, like the problem the libraries face, can they charge the users for the expense of picking out a book for them.
Weart:I want to get back to some of these things, but first I want to get back to your work on the sun in 1960, your general theory of the 22 year cycle; Iím very interested in how that came along.
Babcock:Of course Iíd been thinking about these observations of the sun and the stars for a number of years. While we had got out a couple of papers around 1955 on reporting observations of these magnetic features on the sun  I felt that something more ought to be said about them, I guess I was thinking deeply enough about the whole picture to try to make a more general concept out of it, to see if I couldnít synthesize ideas about a number of observations, about a number of phenomena.
Weart:You would just sometimes sit down and think about it when nothing else was happening, or -?
Babcock:I think I began to think about it and then to draw some sketches, and when I began to do that I could see, well, this isnít good enough, letís try some variations, and so on. Out of it came these notions about flux ropes submerged under the surface, and the loops breaking the surface, and then the twist coming in, and so forth.
Weart:Did you have little pictures in your head, or sketching?
Babcock:Yes, Then when I sat down to try to write it up, I found it was necessary to make some diagrams or sketches, and so I had to try to improve on those a little bit,
Weart:Have you saved any of these preliminary sketches? They would be fun to see.
Babcock:I guess the significant ones were just sort of tidied up for that Ď61 paper, Anyway, I felt rather happy about that, I felt it was significant, and I did give a Wednesday afternoon talk on it down here.
Weart:At Cal Tech?
Babcock:Yes, It didnít generate much comment. About the only one I remember is that when I got through Zwicky said, ďLook, youíve got to give more emphasis to the important points. Youíve got to tell them when youíre coming to something important,Ē Thatís the one comment I got out of it, But I felt some satisfaction in that paper, even though itís imperfect in some respects, I suppose a year later, I wished that I could do it over again and improve it, But I felt it was worth doing, and I had some pride in it.
Weart:Where do ideas like that come from in general, do you think? Where do you get your ideas like this from? Why does this idea come along at that particular time, rather than earlier or later?
Babcock:I feel that we had accumulated quite an important set of new observations, essentially at the Hale Solar Laboratory: the systematics of bi-polar magnetic areas and ďunipolarĒ regions, There was an opportunity to synthesize this new knowledge with other data of long standing: Haleís sunspot laws, and a number of other well-known facts about sunspots, coronal streamers, etc. that have been known for a long time, Perhaps they could be fitted into a general concept. And I just thought, well, itís worthwhile trying to see how many of them will fit in connection with this model.
Weart:Weíre resuming after lunch, Now I want to back off a bit and talk about the observatories and how theyíve functioned over the last 30 years since youíve come here, their relations with Cal Tech and so on. Thatís a big question. Weíll get to specifics. But what in general do you think have been the most important things in the observatories, the main things that have been constant and the main things that have changed in the character of this place?
The basic assets have been the wonderful instruments on Mt. Wilson, the 60-inch and the 100-inch, These were the biggest telescope of their time. The 60-inch and the 100-inch were built to new levels of mechanical and optical quality and were located at an excellent site, and of course have been exceedingly productive. So the observatory staff had the benefit of this fine instrumentation and had unique opportunities. The main scientific output of the staff, using the instruments, is well-known, I suppose if one had to choose a single achievement it would be the work of Hubble and Humason on the expanding universe, and this is identified with the 100-inch telescope on Mt. Wilson.
It certainly was one of the main supports for Haleís success in raising funds for the 200-inch funds which came from Rockefeller sources. Of course, the 200-inch was placed at Palomar, and we built really as a joint effort, although the actual responsibility for construction and the ownership of the 200-inch belong to Cal Tech. Following completion of the 200-inch, of course weíre all aware that the effort to develop astronomy at Cal Tech, both as a teaching department academically and as a research organization, got a great deal of impetus. The decision to operate the two observatories, Mt. Wilson and Palomar, with joint support from Carnegie and Cal Tech, was a very basic one, And I think this functioned reasonably well under Bowen, Over the years weíve seen a very great increase in the activity in astronomy and astrophysics. Things have really been burgeoning and the end is not yet in sight. But the activity has not stayed within the bounds of optical astronomy.
There have been all sorts of advances in radio astronomy and high energy astrophysics and theory, laboratory astrophysics, planetary science, The onset of the space age had a great deal to do with public awareness and support. One of the important issues has been the development of the teaching of astronomy at Cal Tech, and it has become one of the outstanding graduate schools, perhaps the outstanding graduate school in the country, according to some surveys.
This has been of very great importance to all the local activity in astronomy. One important decision made by Bowen about 1951 was that radio astronomy as such would not he conducted by the Mt. Wilson and Palomar ohservatories; the observatories would remain out of that, and let radio astronomy be conducted by the division of physics, math and astronomy at Cal Tech, So the Mt. Wilson and Palomar Observatories have done practically all their work in what you would generally call optical astronomy this includes infra-red and so forth.
Weart:Why did he make that decision, by the way?
Babcock:Bowen felt that the techniques were so different far radio astron any that many of the people were thinking about different things, and that it would just not be a very compatible kind of activity. He felt nevertheless that the actual research workers can easily talk to each other and have common meetings and seminars where the results can be discussed, but that the technical observatory work, the backup would better he handled separately.
Weart:One of the specific things I wanted to ask you is, what kinds of contacts have there in fact been between the observatories and the radio group and also in general, Cal Tech astronomers and physicists?
Babcock:Well, the radio astronomers have their offices in Robinson, the same building where the optical astronomers were. We have common conferences in astrophysics. The radio astronomers participate.
Weart:Here in this building?
Babcock:On campus. The Wednesday afternoon seminars are essentially joint with the radio astronomers. Students in astrophysics can take courses in radio astronomy, or whatever, as they please, and some members of the academic staff hold dual positions, as professor of astronomy and professor of radio astronomy at the same time. Staff members of the Hale Observatories, as we call them now, may observe from time to time at Owens Valley with radio telescopes. And the reverse is true as well.
Weart:The staff members down there or professors can use your telescopes?
Babcock:Well, Iím thinking of Wal Sargent now, whoís normally an optical astronomer and has made radio observations at Owens Valley, And certainly some of the students, graduate students from Owens Valley, have observed optically, So thereís no firm boundary here, and in fact we encourage crossing over.
Weart:What about contact with Cal Tech students and so forth? How much contact do you and the other staff members here have with graduate students?
Babcock:Some of the staff who have offices here at Santa Barbara Street serve on PhD committees for graduate students at Cal Tech and take part in the PhD exams, or may be thesis advisors, There are students who do a good deal of observing both at Mount Wilson and at Palomar Mountain. We have a group of staff members called the Student Observing Committee that looks after the interests of the students, coordinates their requests for telescope time, and ensures that they do get time on the telescopes. We occasionally have part-time summer jobs for students in various parts of the observatories,
Weart:Have you ever been a thesis advisor for a student?
Babcock:No, I have not been, myself.
Weart:Would that he fairly tWhical for the staff members here?
Babcock:Not really, Leonard Searle is now serving on such a thing. Sandage has done so, and so have a number of other staff members. Of course, there are several research fellows, some with offices here, others on the campus. These are people who are benefiting, one would say, from the educational opportunities here, We do what we can to give them opportunities for research at the telescopes and so forth. We try to give them the maximum amount of freedom to pursue their own research interests, without obligations.
Weart:The research fellows is a new development since you first came here, is it not? At what point did these research fellows begin to appear?
Babcock:Research fellowships have become more numerous in recent years, but there were some in the 1920ís and 1930ís. In the 1930ís there were a few fellowships offered, for example, by the National Academy of Sciences — National Research Council. Then there were Commonwealth Fellows, young British astronomers with fellowships from their own country, who came here, Thackeray and Woolley, for example, and Oort before them, from Holland. So there have been a few of these for a long time. With the establishment of Carnegie Fellowships in 1948, with more recent fellowships supported by NSF, thereís been a great increase in the number of research fellows, and of guest investigators.
Weart:I see. So it wasnít any particular decision that the observatories took, it was simply that the opportunity appeared?
Babcock:The Carnegie Institution, for some 30 years has supported from three to five Carnegie Fellows at the Hale Observatories. This has been a deliberate policy to increase opportunities for young astronomers, More recently, three Los Companos fellowships have been added.
Weart:Did that change the atmosphere here at all, when larger numbers of new young astronomers began to appear?
Oh yes, of course, the general expansion of research in astronomy changed the atmosphere considerably. Itís hard to say how much was due to just the appearance of research fellows. There have been so many very pronounced changes in the observatories, the way they function and the rest, and there are many causes lying behind all these changes. Of course, the increased popular interest in astronomy, and the consequent support through NSF of the nationís effort in astronomy, and the great increase in the numbers of students — all of these have some sort of common origins, I suppose. But then at the same time thereís been a great shift in the way organizations operate. Iím thinking particularly of the organizational structure of a particular observatory, letís say, where 40 years ago or 50 years ago you had a director who had entire responsibility for spending all of the money and the organization and had complete say as to how every little thing was done.
Nowadays things are indeed very different. Thereís a general questioning today of any authority, of course, and things tend to be done more by consensus. To a very heavy extent, individual astronomers now depend on drafting their own research proposals, which go off to the National Science Foundation or some other agency, and so the basic decisions in large part are made by those agencies or by their advisory panels, and not any more by observatory directors. This has been a very significant change in the way these observatories operate. One result is that individual scientists have far less time for productive research.
Weart:Was this a change that was already becoming quite apparent before you became director? Or has it become stronger since then?
Babcock:Itís certainly become stronger since then, It was becoming apparent even in the middle sixties.
Weart:What other reasons? You mentioned the numbers of young people, the popular feeling, the growth of the National Science Foundation? Any other reasons or important steps in this process? Itís an interesting process.
Well, maybe I can take just a couple of minutes to retrace some of the developments. Going back to the 1940ís, we had here at that time, at Mt. Wilson and Palomar, by far the most capable large telescopes. Many very capable astronomers at other places, universities in the East, were justifiably somewhat jealous, I think, of the great opportunities that people had here. On the other hand, the directors here and the staff were quite well aware of the special advantages they had, and they tried to develop policies to broaden the use of the instruments. Bowen, when he became director in Ď48 and Vannevar Bush, President of the Carnegie Institution were very strong on developing the guest investigator policy for bringing in outside astronomers to use these facilities here, to broaden the opportunities.
At the same time Bowen did all that he could to disperse the special technical information that people here had about instruments auxiliary instruments, telescopes and all the rests In other words. Bowen set out to encourage construction of other telescopes and astronomical instruments at other places throughout the country. Particularly in the West where the observing conditions are good. Results of this effort are seen in the Kitt Peak National Observatory and in the 120-inch telescope of the Lick Observatory. Vannevar Bush was instrumental in establishing the National Science Foundation. Including its attention to astronomy. Other people involved included Robert McGrath and Bowen and other astronomers. The effort among these people as far as astronomyís concerned, was to ensure that the National Science Foundation should make available government funds for better support of astronomy at several centers of excellence if you like, around the country in particular to augment the building of bigger and better telescopes, for giving more opportunities to more astronomers.
And associated with this there should be some national observatory, at a good location, where many astronomers could come. So out of this eventually came Kitt Peak. I think that one development that was not foreseen by the founders of NSF was that Kitt Peak would become a national center, to the extent that all of the major sustaining support from the NSF would go to that one center, and that it would be built up — but that at least as far as optical astronomy goes, there would be little or no support, in a sustained way, to other observatories such as Lick Observatory, the University of Arizona, Mt. Wilson-Palomar and others.
Babcock:Not initially, Iím sure, The idea was in the fifties that you do all you can, and the amount of government funding will not be terribly significant, but it might help the University of Arizona to build another telescope and so on. What people did not count on then, I think, was Sputnik and all that followed— the tremendous swing-around of public opinion in support of the space age, and all the spinoff from that, which really meant a far greater degree of support for astronomy than had been anticipated in the fifties.
Weart:By the way, was there resistance here in the fifties to the idea of taking public funding, government funding?
Babcock:There was some, Merely in the sense that on principle itís better to have some observatories privately funded, and perhaps other publicly funded, but that they should retain their special qualities, and some kind of healthy competition would be a good thing. It has been the policy of the Carnegie institution that at the very least salaries of the professional staff would be paid by the Institution, But for ten years or more, Carnegie Institution has indeed accepted many government grants for research and for auxiliary instruments. Cal Tech has done even more of that, of course.
Weart:You were saying that post Sputnik national funding grew so great that it almost overshadowed this?
Babcock:Yes, There seems to be a real discrepancy, in the sense that the federal budgetary support of Kitt Peak is several times greater than the private support that Mt. Wilson-Palomar can enjoy, I mean, youíre talking about factors of five or ten or something of this sort. This is out of line, When observatories like ours, or Arizona or Hawaii or some others, request a relatively modest sustaining grant to help with the background business of just operating — when these requests go to NSF or Congress, theyíre turned off, Partly perhaps because administrators feel the country should have one national center, thatís the efficient way to do it, why bother with these other outfits? For whatever reason, it has brought about some very severe problems, and I think has gone so far as to be rather unhealthy.
Weart:Has it also made it more difficult to raise private funds, the fact that thereís so much federal funding already in astronomy?
Babcock:Yes, Iím sure this must be the case. Raising private funds seems to be increasingly difficult.
Weart:We should get back to some of these things. But now to go back, before I forget, to early days and so forth, how things have changed, I notice that back when you came here first, Ď47 for example, that there were separate categories in the research division. There was the solar physics division. There was the spectroscopy division under Merrill and the nebular division under Hubble. I wonder, to what extent did these involve real distinctions? Did people have offices on different floors, or —?
Babcock:I think perhaps youíve over-interpreted what Iíve said. There wasnít any rigid separation into divisions.
Weart:No, Iím talking here about the official report, that thereís official separation —
Babcock:— oh, that, Well, that was a matter of convenience, I think, when Adams or Bowen put the report together. Actually, in regular operations here, we didnít feel bound by divisional distinctions, Primarily, there were individual scientists, personalities, pursuing their research interests, Operationally, there were the ďlight-runĒ observers and the ďdark-runĒ observers, as dictated by oneís need for a dark (moonless) sky. This distinction gave rise to some whimsical rivalry, but had no deeper meaning. In the earlier days one could say Arthur S. King was in charge of the physical lab.
Babcock:Arthur King, Robertís father, Now, maybe one could speak of the nebular division, but it was mainly a matter of research interests and the requirement for dark-of-the-moon observing time. To a limited degree, people in one kind of specialty perhaps had their offices in one section of the building, but there was nothing very definite about that.
Weart:You would recognize that some people tended to specialize in extra galactic, and some people tended to specialize in stellar spectroscopy, and so on?
Babcock:Yes, thatís right. You had Joy, Sanford and Merrill they were the heavy duty stellar spectroscopists, and their offices were close together.
Weart:The heads of the research sections didnít have any particular vote? Did Merrill have much to say about what would be done in spectroscopy, and Hubble about what would be done in nebular work?
Babcock:I think not to any very important degree, Oh, it is true that Bowen consulted Merrill if, say, there was to be a new appointment made, some junior staff member; and if a new spectograph were needed there would be consultations among the people who might want to use it, But pretty much, individual staff members made their own real choices about what they were going to work on. Iím sure that Baade never took any direction from Hubble about what he was going to work on, and Minkowski also thought up his own research interests and carried them out. These boundaries were a bit fluid, But to some extent, there was separation into these sections, if you want to use the word.
Weart:Has there ever been an attempt to keep some sort of balance between spectroscopic, letís say, and nebular work? Now Iím thinking over the whole span of Bowenís administration and yours.
Babcock:I expect, particularly in Bowenís day, there was an effort to keep things in balance, Bowen debated, for example, whether to continue work in solar physics here, About 1950 he thought possibly that should be phased out, It hasnít happened yet, In fact, Bob Howard is making great progress in this field, But I think when it came to taking on a new staff member, thought would be given to maintaining a balance.
Babcock:Only to a very limited degree, Nowadays, at least, when a staff member wants to plan his research heís really entirely free, and by himself he can decide what heíd like to work on. He puts in a research proposal and says he wants so much telescope time (dark or light) time on a certain telescope next year, In general this thing gets reviewed by the Observatory Committee, but if itís a meritorious program he will get the nights insofar as the nights can be found by splitting up all the demands.There is practically no effort here for anybody to tell some fellow that heís going to work on radio galaxies, for example, In fact, itís understood that when a staff member does get nights assigned, say on the 200-inch, on the basis of some proposal, after those nights have been assigned he is quite free to change his research aims and work on something else.
Weart:I see, He doesnít have to follow his proposal at all.
Weart:I see. But in terms of hiring new staff, what are the scientific criteria. You wouldnít hire somebody whose specialty had been celestial mechanics, I presume?
Babcock:Right. Our telescopes are not suited to astrometrv and our budget precludes expansion into non-observational fields. The main thing is to get bright young people who obviously have a good future, who have a good start, and who have a little breadth, that is, some experience at more than one place. And since we often feel some weaknesses on the instrumental side, attention might be given to the promise that an individual has for developing newó
Babcock:Well, Iím thinking now of people like (Steve) Shectman and(Eric) Persson. Also, there might be some consideration given to the willingness of a man to do research in the Southern Hemisphere. If heíll seize the opportunities available by going to Chile, this would be significant; if heís the kind that says, no, he wants to sit right here and work at home, well, that might have effect.
Weart:One other difference I notice between the staff now and the staff, I guess at all observatories, 30 years ago, is more interest in people who really know their physical theory, How has this arisen? Was there some point when you could notice a shift towards people who were astrophysicists rather than strict astronomers?
Babcock:There is a real difference between astronomy and physics, although the boundary is diffuse. Many people cross over, especially from physics to astronomy. Nowadays, almost every student who goes into astronomy realizes itís advantageous to get all the physics possible, and most of them try to do this. On the other hand, some of the rather classical kinds of physics that I used to think were very important, like spectroscopy or optics, seem to get too little attention these days. So you probably pay a little more attention to the manís originality and what he has done, say, during his thesis years, and what his thesis advisor says or what his colleagues say.
Weart:To get back, you mentioned the Observatory Committee a few minutes ago, and I wanted to ask you some questions about that, You joined the Committee in 1952; I guess youíve been on it ever since, The first question is, in the original agreement this is ďadvisoryĒ I wonder to what extent, both with Bowen and with you, has this Committee affected what the Director would do?
Babcock:Well, the advisory nature is still recognized or stated from time to time. In many cases though, in reaching important decisions, the subject has been discussed pretty fully in the Committee, and one asks for opinions The Director may in fact have a somewhat formal vote taken in the Committee to see whether its unanimous or not, The Director, I think, would very rarely make a decision that went against the opinion of several members of the Observatory Committee.
Weart:Has the influence of the Observatory Committee changed at all over the last 20, 30 years? Its role?
Babcock:Yes, its influence has changed to some extent. It has become larger. And whereas years ago, say in Bowenís day, he personally kept his own notes on the deliberations of the Committee, nowadays things are different. The minutes of the Committee meetings are kept by a recorder, a member of the Committee, and then circulated to the whole staff.
Weart:Oh, is that so? So they must be a little restrained about what they put in the minutes. Is the discussion in the Committee pretty frank?
Babcock:Itís often pretty frank. Sometimes the director has a chore in holding the Committee members down to the agenda. Once in a while, it tends to be used as a sounding board for some Committee member to get his views broadcast to the staff, which really is deviating from the proper function of the Committee. Because the whole staff as such also meets. This shows that there is a chance for any staff member to have his say.
Weart:When did these start, the meetings of the whole staff? How did that come about?
Babcock:In the old days, the ďJournal ClubĒ meetings every Monday served as staff meetings, More recently, occasional staff meetings have been held, sometimes in the form of lunch meetings at the Athenaeum. Such meetings are now held once a month. Other staff meetings are convened for special purposes. The joint agreement by which the Observatories operate specifies that there shall be at least four staff meetings annually.
Weart:OK. How have these staff meetings functioned? Have they contributed much, in any particular direction?
Babcock:They have helped to develop a sense of unity among the staff and have given people a chance to express opinions on observatory policies. I recall that one of the most significant staff meetings was in 1970. We had just been informed that Mr. and Mrs. Greenewalt had offered quite a sizeable gift to the Carnegie Institution to build a new telescope in Chile and they specified that the telescope should he designed according to specifications set down by the staff. Well, the staff reviewed this and accepted the proposal with great enthusiasm. As a result the gift was received by Carnegie, and the Carnegie Institution augmented the gift, and the telescope was built. This was one occasion that was very nearly unanimous. There have been many staff meetings concerned, quite rightly, with the problem of finding operating funds for the observatories in these times.
Weart:Thatís been one of your persistent problems.
Babcock:Yes, And the staff as a whole has assisted in drafting very special proposals to the National Science Foundation. There was a big effort in 1972 to get sustained support that would assist in meeting the basic operating requirements of Mt. Wilson and Palomar. This was turned down although not without some expressions of real sympathy from the Astronomy Advisory Panel at NSF.
Weart:It was turned down at a higher level?
Babcock:It was turned down probably at a higher level. Anyway, weíre operating on the basis that good proposals from individual scientists to do good research will be favorably received by the NSF, and that we should include here requests for some of the incidentals and overhead. This helps a little, but it still doesnít really permit the Observatories to meet their obligations, to keep the instruments operating at a proper level and to provide properly for outside observers.
Weart:Iím interested both within the Observatory Committee and within the staff meetings, but mainly the Observatory Committee, going back from the fifties onward in what kinds of differences there may have been, Not because Iím particularly interested in conflict, but because this is sometimes where you can see what the basic philosophies are. Do you know, have there been any sort of persistent, letís say persistent for ten years or whatever, differences in philosophy between different groups on the staff and the Observatory Committee? In the philosophy of the scientific or administrative direction things should go?
Babcock:Yes, of course there have been differences in outlook. And weíre not all one big happy family, In part, the problems have arisen because of the expansion in all of the work in astronomy and astrophysics. Itís no longer quite the simpler sort of activity that it was. As I mentioned before, you have all these related fields, theory, relativity, laboratory astrophysics, radio astronomy, planetary sciences, and so on, the Cal Tech side, this means that the activity is now distributed among a number of people whose offices are in different places on the campus, and they donít feel any particularly strong association with the Hale Observatories as an organization. They benefit from the use of the facilities. They think of the Observatories as some mountain locations up there where there are instruments, and they think that somebody ought to keep those instruments in good share.
Weart:Itís just one more facility.
At the very start, in 1948-50, it was felt that the function of the Observatories was to pursue research in astronomy, and all the staff members did their research in the Observatories. Apart from that, some held professorships at Cal Tech and had teaching responsibilities, but those were quite separate; those were activities in the Division of Physics, Math and Astronomy, So teaching was one thing they did with part of their time, but when they did research in astronomy, it was as staff members of the Observatory. Of course, that distinction tends to become blurred, and I think most of our staff members on the Cal Tech side donít pay much attention to that. When they do research, they think of themselves as professors.
So the identity of the observatory as such is not maintained as clearly as it was at one time. And this leads to some misunderstandings, I think particularly on the part of outsiders. For example, if some of our staff members want to have a big part in the Large Space Telescope project, which might take a considerable fraction of their time in the future, do they pursue that as staff members of the Hale Observatories? Or do they pursue that as professors at Cal Tech?
Weart:What would you do in a case like that? Can a person be Hale Oservatories person and yet be totally occupied with some other telescope?
Babcock:This could happen, I think the idea would be that as long as a person maintains staff membership, and provides material to the Director for the annual report, and perhaps serves some functions on staff committees or whatever, he will be a staff member, And this means that his proposals to the federal agencies would come through the Observatory Committee and he approved by the Director, If it gets to the point where he wants to pull out from all of that, and just be a professor who perhaps works with some facility outside of the Hale Observatories purview, my feeling is that he can do that, but then he probably should resign from the Observatory staff.
Weart:I see, Could a person fairly readily move from the observatory to Cal Tech or back? Has there been much exchange of personnel this way, that a person would be a staff member here, and then afterwards become a professor at Cal Tech or vice versa?
Babcock:But let me make completely clear for the record, the scientific staff of the Observatory has about 20 staff members, And about ten of these are supported by Cal Tech, about ten by Carnegie. Those supported by Cal Tech are also professors at Cal Tech.
Weart:Oh, so youíre referring to the people who are already supported by Cal Tech.
Weart:I see, I understand, OK, also Iím interested - weíve been talking about the differences between Cal Tech and Carnegie, but were there any philosophical differences or maybe differences of scientific outlook that perhaps cut across these lines?
Oh yes. There are some important ones. The Observatories are viewed differently by Cal Tech and by Carnegie. The Carnegie Institution has about five operating research departments dispersed around the United States; the Observatories are one of these. And from the Carnegie side, a department is an organization that has a Director who has a great deal of authority for what goes on. He oversees the expenditure of funds; he guides the research; heís directly responsible to the president of the institution; he provides the detailed annual report, and so on.
From Cal Tech side, itís very hard to maintain even the identity of the Observatories as an organization that is operated jointly with the Carnegie Institution. The whole thing gets quite blurred. Actually the fact of ownership of Palomar by Cal Tech seems to count very strongly on the campus. So the concept of partnership with the Carnegie Institution to conduct a unified research in optical astronomy in the Hale Observatories with scientific staff is not very firmly supported by Cal Tech.
Weart:I see, I guess when it comes to scientific programs, itís really a problem of assigning telescope time on the 100-inch and the 200-inch. And I wonder, how has this process changed over time, the process of deciding who gets how much, how many nights on the instruments?
Babcock:I can outline it first as it was carried out in Bowenís time, In those days, Bowen would circulate the staff in September and ask for the proposals for use of the 200-inch by the staff in the coming year, He would want pretty good scientific justification for time to be allocated on the 200-inch.
Weart:Meaning a few paragraphs or a few pages?
Babcock:A page or two. If the time on that basis was oversubscribed and it might be for the dark time I think what often happened was that the interested staff members would get together. Thereíd be Hubble, Minkowski, Baade, Zwicky and two or three others, and theyíd have a meeting and arrive at a division of time, Of course Bowen would be there.
Weart:Did you take part in any of these meetings?
Babcock:No, This would be, if you like, the nebular department or the dark-time people.
Weart:And the light time? Was there a problem?
Babcock:The light time might be the same, but the competition wouldnít be quite so severe for the light time. Anyhow, in some such way, rather informally, Bowen would arrive at the allocation of dark time on the 2OO-inch. As for other telescopes, the oversubscription wasnít extreme and usually could be worked out by just trimming off a couple of nights here or there and fitting things together.
Weart:I see. Essentially Bowen was the final authority on this.
Babcock:If there were real conflicts, he would present the situation to the Observatory Committee, and there would be some opinions expressed. There were, for example, strong conflicts of opinion about such things as the way the 48-inch Scmidt should be used in the l950s.
Weart:I wanted to ask about that specifically. Tell me about that now, since it came up.
Babcock:When the 48-inch first became operational there was just a little time given to certain tests, Baade got a few plates of a few clusters and whatever. Then Bowen said, ďThe most important thing we can do is to conduct the sky survey. This will be of great use, both for us and other observatories everywhere, itís highly important for the benefit of astronomy in general. The 48-inch is quite unique, and it will be a very worthwhile jobĒ. He insisted on this over strong objections from Zwicky. Zwicky said we should at least have half the time of the telescope for current research by the staff. ďLots of very important things that I must do, right away — these have to be doneĒ
Weart:That sounds like Zwicky.
Babcock:Well, Bowen prevailed, but the conflict was pretty stiff there, The staff didnít get any time on the 48-inch for years, About six years or so was devoted to the Sky Survey, and of course it was very successful, Dozens of complete copies have been made, and they continue to he made. They are distributed at cost to other research groups. No other survey has approached it in value.
Weart:This was essentially because Bowen insisted on it.
Babcock:Bowen insisted on it.
Weart:Did other staff members agree more or less with him?
Babcock:Most of the staff agreed with him. The Observatory Committee heard Bowenís statement. I think Baade agreed with that, or maybe Baade helped to generate the opinion in the first place. The value of the sky was appreciated. Minkowski certainly was in favor of it and he was pretty influential; as you know, he had real charge of the survey for most of its duration. (Al Wilson was hired to take the plates, at least at the start, later followed by others.) So the survey was successful. It certainly has been worth doing. Eventually, beginning around Ď58 or Ď59, the telescope was opened up to the staff.
Weart:I see, Now, to get back to the problems of allocating telescope time, youíve described how it was under Bowen, How has that changed?
All right. In recent years there have been increasing demands for time, especially dark time, on most of the instruments, from staff and from guest investigators. And so weíve gone through a more foal process of requesting, once a year, that research proposals should come in, really for all telescope time that the staff wants — and research fellows and students. Did their research in the Observatories, Apart from that, some held professorships at Cal Tech and had teaching responsibilities, but those were quite separate; those were activities in the Division of Physics, Math and Astronomy. So teaching was one thing they did with part of their time, but when they did research in astronomy, it was as staff members of the Observatory.
Of course, that distinction tends to become blurred, and I think most of our staff members on the Cal Tech side donít pay much attention to that. When they do research, they think of themselves as professors. So the identity of the observatory as such is not maintained as clearly as it was at one time. And this leads to some misunderstandings, I think particularly on the part of outsiders. For example, if some of our staff members want to have a big part in the Large Space Telescope project, which might take a considerable fraction of their time in the future, do they pursue that as staff members of the Hale Observatories? Or do they pursue that as professors at Cal Tech?
Weart:What would you do in a case like that? Can a person be Hale Observatories person and yet be totally occupied with some other telescope?
Babcock:This could happen, I think the idea would be that as long as a person maintains staff membership, and provides material to the Director for the annual report, and perhaps serves some functions on staff committees or whatever, he will be a staff member. And this means that his proposals to the federal agencies would come through the Observatory Committee and he approved by the Director. If it gets to the point where he wants to pull out from all of that, and just be a professor who perhaps works with some facility outside of the Hale Observatories purview, my feeling is that he can do that, but then he probably should resign from the Observatory staff.
Weart:I see, Could a person fairly readily move from the observatory to Cal Tech or back. Has there been much exchange of personnel this way, that a person would be a staff member here, and then afterwards become a professor at Cal Tech or vice versa?
Babcock:But let me make completely clear for the record, the scientific staff of the Observatory has about 20 staff members. And about ten of these are supported by Cal Tech, about ten by Carnegie, Those supported by Cal Tech are also professors at Cal Tech.
Weart:Oh, so youíre referring to the people who are already supported by Cal Tech.
Weart:I see, I understand, OK, also Iím interested - weíve been talking about the differences between Cal Tech and Carnegie, but were there any philosophical differences or maybe differences of scientific outlook that perhaps cut across these lines?
Oh yes. There are some important ones. The Observatories are viewed differently by Cal Tech and by Carnegie. The Carnegie Institution has about five operating research departments dispersed around the United States; the Observatories are one of these. And from the Carnegie side, a department is an organization that has a Director who has a great deal of authority for what goes on.
He oversees the expenditure of funds; he guides the research; heís directly responsible to the president of the institution; he provides the detailed annual report, and so on. From Cal Tech side, itís very hard to maintain even the identity of the Observatories as an organization that is operated jointly with the Carnegie Institution. The whole thing gets quite blurred. Actually the fact of ownership of Palomar by Cal Tech seems to count very strongly on the campus, So the concept of partnership with the Carnegie Institution to conduct a unified research in optical astronomy in the Hale Observatories with scientific staff is not very fully supported by Cal Tech.
Weart:I see, I guess when it comes to scientific programs, itís really a problem of assigning telescope time on the 100-inch and the 200-inch. And I wonder, how has this process changed over time, the process of deciding who gets how much, how many nights on the instruments?
Babcock:I can outline it first as it was carried out in Bowenís time. In those days, Bowen would circulate the staff in September and ask for the proposals for use of the 200-inch by the staff in the coming year. He would want pretty good scientific justification for time to be allocated on the 200-inch.
Weart:Meaning a few pages or a few paragraphs?
Babcock:A page or two, If the time on that basis was oversubscribed and it might be for the dark time I think what often happened was that the interested staff members would get together. Thereíd be Hubble, Minkowski, Baade, Zwicky and two or three others, and theyíd have a meeting and arrive at a division of time, Of course Bowen would be there.
Weart:Did you take part in any of these meetings?
Babcock:No, This would be, if you like, the nebular department or the dark-time people.
Weart:And the light time? Was there a problem?
Babcock:The light time might be the same, but the competition wouldnít be quite so severe for the light time. Anyhow, in some such way, rather informally, Bowen would arrive at the allocation of dark time on the 200-inch. As for other telescopes, the oversubscription wasnít extreme and usually could be worked out by just trimming off a couple of nights here or there and fitting things together.
Weart:I see, Essentially Bowen was the final authority on this.
Babcock:And also from outsiders, would-be nest investigators. All of these requests are received here by the end of October. Then once a year we have a big review of all the requests. The requests are replicated and theyíre sent around to members of the Observatory Committee or a subcommittee. The result is that a working committee of about five or six members, in November, goes over all these proposals and goes through the difficult business of allocating time. The most difficult of all is dark-time on the 200-inch, but we list all the telescopes.
Weart:Are you a member of this group always?
Babcock:Iím a member of the group, although in recent years Iíve not been chairman of the subcommittee that really allocates the time. We have to have members from the dark-time people, the light-time people, and the like.
Weart:Does it rotate, the membership?
Babcock:The membership changes somewhat from year to year, yes.
Weart:Itís not a regular rotation, itís just Ė
Babcock:— itís not a regular rotation. We wouldnít just rotate members of the Observatory Committee because, some individuals are too specialized in their interests we have to restrict it mostly to people who really use the stellar telescopes to a considerable degree. Anyway, this committee trims down the allocations to fit the number of nights available, by quarters. Then the director has the job of getting out all the notifications to staff and to guest investigators outside telling them what they get or do not get in relation to their requests. Many adjustments have to be made. In recent years weíve had 50 to 60 nest investigators annually.
Weart:My goodness, with only a few nights each, then—
Babcock:With too few nights each. Weíre trying to change this policy and restrict the number, trim the number of guest investigators each year, and to make it more worthwhile — by giving a greater number of nights to those who are invited.
Weart:What has determined what percentage of the nights will be given to guest investigators, over the years?
Babcock:This is a difficult point with respect to the 200-inch. We have set a limit of 20 percent on the amount of dark time on the 200-inch that goes to guest investigators.
Weart:This was essentially a decision of the Observatory Committee?
Weart:And has this changed over time, or has this been steady policy?
Babcock:Itís been fairly steady for some time now. As for the other telescopes, those that are in greatest demand— well, we give pretty heavy consideration to the staff, but very often we will trim back the staff considerably in order to give time to outsiders. This is often very important on the 48-inch Schmidt, and on the Palomar 60-inch and Mt. Wilson telescopes. But it is perfectly true that our own staff now takes a smallish fraction of time with the Mt. Wilson 60-inch, and temporarily also with the 100-inch. But there is increasing demand in the future for the 100-inch. Sandage has a 15-year program, a heavy one, that he wants to initiate with the Mt. Wilson 100-inch. Thereís a big proposal in the works on that.
Weart:I see, and a lot of discussion, Iím sure.
Weart:Tell me, over the years, going back to the time in the fifties when you first became involved in this, have there been any particular priorities set on the kinds of people that would come? For example, do you search for people who have had experience with large telescopes before? Or those who havenít used big telescopes before? Are there particular places you like to have people coming from?
Babcock:We like to have competent observers, with meritorious programs, that are of real current interest, However, we frequently train guest observers in the use of equipment new to them, We tend to phase out long continued, old-time programs unless they are producing genuinely useful results. We also have a policy that we donít accept graduate students from another institution who are beginning observational work for a thesis at some other place. We feel we have some responsibility to the Cal Tech students, But apart from that, we try to allocate the time on merit, insofar as the equipment is available.
Weart:Has dark-time always automatically been given to nebular work and cosmology?
Babcock:No, there is not any real distinction as to whether itís cosmology or not.
Weart:I see, Has there been any change over time in the proportion of time that will be allocated to cosmology? Any pressures either way?
Babcock:No. I think we try to avoid basing the choice on whether itís cosmology or not. There have been some problems about competition among individuals or groups right on our own staff who want to carry on work in parallel, but still not in collaboration.
Weart:You mean they have similar programs, Everybody wants to find the red shift of Ė
Babcock:Maybe somebody has a long-standing program in a certain field, oh, to study letís say clusters of galaxies and work on the brighter members and so on. And then somebody else, without mentioning it to the first individual, wants to just initiate work in the same field, Some have the opinion that people on the same staff ought to discuss these things and see if they can collaborate and work jointly to split up the opportunities, to make it more effective. There have been some cases where this simply has not happened, and we have not been able to avoid some direct competition. That may not be all bad.
Weart:Has there been any change over the last 20, 25 years, in pressure for time? Has there been increasing pressure for dark-time or for cosmological type of work or has the proportion of proposal of things people want to do in stellar work been about the same?
Babcock:Thereís been increasing emphasis on dark-time observation of faint objects I mean spectroscopy and photometry of faint objects, often connected with cosmological investigations. More and more weíre finding people working on faint things, nowadays turning out large numbers of red shifts of faint galaxies or doing photometry on very faint objects, People are exploiting the new technology thatís available, and theyíre counting photons for some very faint things and extending the limiting magnitude. And this is where some of the great gains are. I was just going to say that more and more there is interest in working on faint objects, where people are counting photons and extending to fainter magnitudes. Interest in stellar spectroscopy, especially at immediate or high dispersion, is diminishing.
Weart:I see, One of the things that I found interesting was that Adams, and to some extent Bowen, and you, and Jesse Greenstein, were all stellar people, essentially, and yet the Hale Observatories are probably best known to the public for cosmological work. Is there any particular reason for this that the directors have been stellar people?
Babcock:I donít know that thereís any very definite reason for that, Just conceivably, to a little bit whimsical, cosmologists donít really seem to get along very well with one another, and it might just have been hard for them to agree on any single person, (Laughter)
Weart:I understand, I wonder if you could comment on the different weight given to these different types of work at the observatories, given that public interest has been so strong in cosmology?
Babcock:My own feeling has been that we should try to maintain some activity in the main fields that the observatories have worked on in the past; that we shouldnít specialize too heavily in cosmology, to the extent of dropping all work in stellar spectroscopy for instance.
Weart:Has that ever been proposed?
Babcock:Itís been seriously questioned whether, for example, we should revise the Coude spectrograph on the 200-inch; itís been seriously questioned whether we should have a Coude spectrograph on the duPont telescope, Because among our own staff thereís not too much interest in such instruments, and because we have a staff limited in number, who all want to concentrate on what they view as the most exciting things today quasars, radio galaxies and all that, I feel that we should build and properly maintain equipment for high dispersion spectroscopy and pursue at least some work there, and offer opportunities to outside astromes. It still is a very valid field of research, and thereís lots of good astrophysics to he turned out there.
Weart:Even 20 years ago, say in the Ďfifties, was there this kind of pressure — people more interested in cosmology than stellar work? Or is this a more recent development?
Babcock:Well, there was a better balance maintained years ago, But I remember some arguments 40 years ago on the mountain, where people talked about what they would do if they got a night of really good seeing. And Hubble was saying, ďWell, if we get a night of really good seeing, we should be able to change over immediately to direct photographv, or something we really need to do for cosmology.Ē And Merrill piped up and said, ďWell, why change over to that? Why not put on the stellar spectrograph? We need the good seeing too.Ē But at least in those days there was somewhat more of a balance in the activity. Nowadays the bright time is more taken up by infrared people, or perhaps some visitors who want to work on interferometric programs of some kind, speckle interferometry, or what have you. So we have little trouble keeping the telescopes busy during the light of the moon.
Weart:Tell me, do you think that thereís been any change in the degree of contact between a stellar worker, say, who works within the galaxy, contact between this kind of work and extragalactic and cosmological work - in terms of the scientific contributions, or just the communication between the different kinds of people? Has that changed?
Babcock:I think people tend to be a little broader these days than may have been the case years ago. At least, you find some people who can shift very readily from one field to another, letís say, from straight cosmology to working on abundance differences across galaxies or within galaxies, shifting from problems of structure of a given galaxy to the structure of the universe. More and more, you find people working in these areas. You find people here. Two of them, Searle and Sargent, a few years back, were working in stellar spectroscopy. They worked on peculiar A stars. Now Sargent is working in cosmology, on quasars and such, and Searle concentrates more on structure of galaxies and abundance differences across galaxies.
Weart:Itís true, itís a kind of shift that would have been less likely some years ago.
Weart:Thatís very interesting. To shift ground again, you mentioned a while back about pre-refereeing, and I did in fact want to ask you about that. Thatís something thatís certainly changed a lot since you first appeared here. So tell me more about the pre-refeering process, what it was like when you first arrived here and how itís changed.
Babcock:The Observatory staff here at Mt. Wilson always used to have an editor. In the early days it was the Assistant Director Frederick Scares. Every paper that was prepared by a staff member had to go past Scares, and he would edit it in detail for English, style and all that. If there were any questions about the science he would see that it got checked out, perhaps by some other staff member. All this was very carefully done. There was some reason for it, because in the early days there was an understanding between University of Chicago and the Mt. Wilson Observatory that papers originating here, for the ASTROPHYSICAL JOURNAL, did not have to be reviewed by the JOURNAL; the reviewing would be done here, Well, that was done, then.
Weart:Was it automatic then that Seares would always go to some referee, or heíd decide it himself?
Babcock:To what extent he went to others, I donít know, but he was a conscientious editor.
Weart:Did he ever come to you to review a paper, to referee a paper, so to speak?
Babcock:I donít think so, because Scares had retired by the time I became a staff member. My little paper, ďHydrogen Lines in the Solar ChromosphereĒ or something of 1933, was edited by Scares. It was only two little paragraphs in the PASP, but he read it carefully. Later that chore was taken over by Merrill. Merrill probably was more didactic, but a little less talented overall, and his scientific insight wasnít too deep actually, But he did a thorough job of editing, So that was carried on until the arrangement was changed sometime in the 1950ís, But it was irksome, and in many instances it led to inferior papers, Poor choice of titles — I was impressed later, after my paper on stellar magnetic fields came out — you see, Merrill said to me, ďThe important thing youíre working on is the Zeeman effect, so it should be ďThe Zeeman effect in 78 Virginis.Ē Well, to my mind the important thing was, the star has a magnetic field, But I could never convince Merrill of that kind of outlook on the thing.
Weart:The title was in fact ďZeeman effect,Ē wasnít it? Now, at least for about 20 years, weíve had no local editor. Papers now are worked up by individual staff members. They go out through a secretaryís office. She merely records the title and so forth and sends the paper off to the journal. And of course the journal is responsible, if they referee it or whatever, and the same secretary looks after the business end of the order. At the same time, a copy of the paper comes to me for my information.
Weart:Just for your information, I see.
Babcock:And a copy goes to three other members of the staff, who constitute the press committee. They are supposed to advise if they think it is worth a news release, We have a procedure for handling that.
Weart:I see, What about in between there, when there was that first transition, from the time it was all pre-refereeing, to the time when the ASTROPHYSICAL JOURNAL began to impose its refereeing. There must have been a transition period in there?
Babcock:My impression is that by agreement, editing of MWO papers for the Ap.J. was ended here and was taken over by the editor of the Ap.J. on a certain date, - probably 1951.
Weart:So he was pro-refereeing, and then it would go to the ASTROPHYSICAL JOURNAL for their refereeing, so to speak?
Babcock:I think the answer is probably yes. Then of course there were some papers that went to other journals, and they were edited. Bowen always like to see any scientific paper before it went out, There was a staff memo that Bowen got out that governed these things, I think up to 1963, that he should see any paper before it went out,
Weart:I see, But nowadays, even if some staff member submits papers which get rejected very frequently or whatever, itís essentially just his private concern?
Babcock:Essentially it is, Yes.
Weart:Although people may have a few things to say about it.
We won't name names. (laughter) OK.
Now, back to some questions about society here. Going back to the fifties and up to the present, where and how did you meet with people from Cal Tech, the physicists for example? Have you personally had much relationship with Cal Tech physicists? Where would you see them?
Babcock:Well, physicists would often come to the astrophysics research conferences, these Wednesday afternoon talks Very often youíd see Willy Fowler, Leverett Davis and other physicists there. Similarly, many astronomers would go over to the physics research conference on Thursday afternoons. Then of course, there have been smaller scale, sort of informal groups that have more or less regular meetings. Thereís the current day journal club.
Babcock:Itís called a journal club, but itís totally different from the old time journal club. This was really organized by Neugebauer. It meets Tuesday afternoons at 4, and itís kind of a little forum where students and others review important papers in the literature, for the benefit of others.
Weart:The old journal club no longer exists?
Babcock:Well, years ago it was transformed into the present Wednesday afternoon colloquium. Itís a totally different thing.
Weart:How did that happen? Was that just because the department there grew larger?
Babcock:The old-fashioned Monday morning journal club was comprised of staff members. It was terminated by 1950. At that time the joint operation with Cal Tech had been begun, and Bowen set up the procedure for having a Wednesday afternoon astrophysics research conference. He set up a little committee that looks after it and lines up the speakers. Itís preceded by tea at 3:30, before the conference. It has evolved from that beginning, Many students attend, We still have a little committee that I appoint, that selects the speakers and then lines up the programs in advance, There are many more outside speakers; the old practice of having each staff member speak at least once a year is no longer observed, We have lost something in that.
Weart:I see. Is there any kind of seminar held up here at Santa Barbara St.? Any kind of get-togethers?
Babcock:Thereís nothing of any regular, formal nature, Nothing beyond the brown bag lunches, But these fluctuate, and theyíre not really scientific gatherings. 17::The tea takes place in the library of Robinson Lab, then the company goes across the way to a lecture room. There might be 20 to 50 attendees. — SW
Weart:I see. People do get together, thereís a lunch room here and they get together at lunch sometimes.
Babcock:Sometimes, Once a week, yes.
Weart:I was wondering if it was formally one day of the week when people do get together?
Babcock:Well, generally on Tuesdays thereíll be some kind of a brown bag lunch, yes.
Weart:I see. Where else do people exchange ideas? Do they socialize after hours very much? Has that changed? You were here in the thirties so u know what it was like then, How has that changed?
Babcock:Itís out of fashion for people to have tennis matches or do anything of that sort. By and large, I think people seldom have any athletic activities to amount to anything. People are too busy. Theyíre getting ready to go to the mountain, or theyíre working up to their necks on a proposal for NSF or whatever. Thereís less observance of regular office hours, certainly, by the staff, hut at the same time not very much in the way of socializing. Of course, more and more today you find that observing with the big telescopes is done by little groups of people instead of just by a single astronomer, so thereís more coordination required, more combined activity, So of course thereís some interchange at the mountain meal times on the mountain are often rather talkative and busy sessions.
Weart:People used to keep pretty regular hours here, you said?
Babcock:Yes, Years ago, that was the case, People arrived at 8 or 8:30 oíclock in the morning, and followed through until they were done.
Weart:You mean in Bowenís time?
Babcock:Well, particularly in Bowenís time. Actually, Adams was a very regular man. He walked from home; he always arrived here at 8:45:00, Bowen liked to start earlier, and he expected everybody else to be on hand at 8. You can no longer, of course, maintain that kind of a schedule for everybody.
Weart:Even if you wanted to, you couldnít.
Babcock:You couldnít very well do that. Youíre speaking of staff get-togethers - we do make an effort now to have a monthly, or letís say a regular staff meeting, usually at lunch, which now is at the Athenaeum. This is a fairly recently resurrected plan, but weíve been carrying it out now for a number of months, and it will probably continue except in mid-summer, About every two or three months at least we have a staff lunch where everybody gets together.
Weart:Is this identical with these Friday lunches?
Babcock:No, those are much less organized. I mean, itís just a custom that people go over there Friday. No, the staff lunches are usually in the private dining room, and we find out in advance who wants to come, and so forth,
Weart:I see, so this would be identical with a formal staff meeting, in a way.
Babcock:Yes, they serve the purpose of a staff meeting.
Weart:I see, By the way do people go much to these Friday lmches? Has this changed over the last 20 years or whatever?
Babcock:I think it has changed a lot, By and large, very few of the staff from Santa Barbara Street go down to the Friday lunches, A Large number of the Cal Tech staff members do, But of course, there seem to be large numbers of students and radio astronomers and so on. I find if I go down, it seems to me that two-thirds of the people I donít know, or theyíve drifted in from physics or whatever. It may be interesting and all that, but it may or may not be very productive.
Weart:I see, Itís not the kind of smaller, more cohesive group, or single subject group, that it used to be.
Babcock:Itís very fluid, yes. Rather unpredictable.
Weart:Very interesting. Thatís sort of a microcosm of all the changes you were mentioning.
Weart:Tell me, youíve said a lot about Ira Bowen, and youíve given me a pretty good picture. But I still donít quite have a picture of his personality, how he was as a person.
He was, I would say, extremely dedicated to doing his job. He put himself thoroughly into it. He regarded it as a great responsibility, and perhaps the greatest part of that responsibility was to see that the 200W inch was used as effectively as possible. Furthermore, beyond that he did want to extend opportunities to outside astronomers, He did everything he could to tell outsiders about how our instruments were built, sent plans of this spectrograph or that photometer to any observatory that wanted to build one, We spent a lot of time entertaining visiting engineers and observatory directors who were discussing new telescopes.
Everything Bowen could do to assist these projects was done. He himself gave large amounts of time to just consulting, free of charge of course, on the Lick Telescope and at Kitt Peak. He went over there time after time, along with Bruce Rule, to give them everything he could about technical matters. He adopted a good many of the fairly firm attitudes about being a director. He had seen how things were at Lick and elsewhere. He was very strong about policies. He wanted to prevent the load on himself from being too great. He felt that he could not or should not hire a business manager. He wasnít very good at delegating jobs, but his idea was to develop policies to cover this circumstance or that, and once a policy was laid down, heíd refer to it or stick to it and use that as the basis for making decisions. Sometimes he was a little too obtuse and would tend to ignore the personalities involved, and there were a few instances where this led to very serious ill feeling against the Observatory. Because he stuck to his policy and arrived at his decision on that basis.
He did operate the Observatories very much by himself. He gave up practically all of his own research, of course, and adopted the idea that he was responsible for the operations. He carried most of it in his head and devoted himself single mindedlv to that job. He was primarily a physicist, although astronomy was his adopted field. He didnít develop much of an appreciation for many prominent astronomers, influential members of the astronomical community, who really were sympathetic with the Observatory and wanted to develop connections here. If it didnít suit him, he could turn people off with a very cold hand. He wasnít much interested in the American Astronomical Society or organizations of that sort, although, as I said, he did devote a great deal of effort to consultations about, say, the foundation of NSF and so on. He had a great talent for spectroscopy and optics, and also for instrumentation, optical instruments.
He did put in a good deal of effort on the design of optical devices in which he was very talented, His own adaptation of the Schmidt camera for spectrographs, and the design of spectrographs as such, and his attention to maintaining the optical quality of the 200-inch, his design of the optics for new telescopes, and particularly for the Dupont telescope — Bowen was very largely responsible for that. Iíve been very pleased that in the last four months weíve gotten the first wide-angle plates with the DuPont telescope, and theyíre beautiful. The optical design was right on (snaps fingers).
Weart:He was involved in the design of that, was he?
Babcock:He really designed the optical system. Itís a Ritchey - Chrťtien, modified with a Gascoigne-Bowen correcting lens. But out of this design he got unusual wide-angle performance with 2,1 degrees for the diameter of the field, with really excellent definition. This is at the same scale with the Cassegrain there that you get at the prime focus of the 200-inch. About 10 seconds of arc per millimeter. And the definition is beautiful.
Weart:Well, Iíll have to see one of those plates.
Babcock:Youíll find one right outside in the hall.
Weart:Tell me, how did he manage this balancing act, which was a new balancing act because it hadnít existed before, between Cal Tech and Carnegie? That is, on the one hand he had some kind of relationship with Carnegie, on the other hand he had a relationship with Cal Tech. How did he work this?
Babcock:Well, he could make it work pretty well. He was an old time Cal professor. He and Lee Dubridge were on very good terms. Bowen was senior to Bacher, and Bowen was also well acquainted with Van Bush. There was no particular problem, I think, In those days, at least through most of the fifties, the budgets were forthcoming. Theyíd increase a little hit each year. I think Bowen really operated on this basis, that he didnít question the budget ceiling that was transmitted to him, either from Carnegie or from Cal Tech. The budget ceiling was given to him, and he was going to operate the Observatories within that ceiling just as well as he could, And to think of requesting more money — oh, no, this would be just out of his orbit, That wasnít his job.
Weart:These budget ceilings kept slightly increasing every year automatically?
Babcock:They kept increasing, and they increased enough to permit things to expand a little bit.
Weart:And within these budget ceilings, did he have pretty complete freedom as to how he would divide up the money?
Weart:On both sides, the Cal Tech and the Carnegie side?
Babcock:I would say on both sides, yes, Bowen was instrumental in setting up the maintenance group at Palomar, and setting up the policies and procedures for operating, everything spelled out. You closed the shutters if the wind gets above 33 miles an hour — every detail was taken care of in policies. Bowen maintained a definite distinction between research on the one hand and academic activities on the other. Everything on the teaching side was part of the Division(of physics, math and astronomy), mostly under Carl Anderson, So Carl Anderson saw to it that the Division conducted the academic work.
Weart:I see. Then, of course, you became Director, Do you have any idea how you were chosen to be the new Director in 1963, I guess?
Babcock:I donít have too good an idea, I do know that Caryl Haskins spent some time out here, and ostensibly got around and talked to most of the staff, Even before this, I had been appointed Assistant Director back in 1957.
Weart:Thatís right, I should have asked you about that in the first place.
Babcock:Well, I knew that Van Bush was aware of this.
Weart:How were you appointed Assistant Director?
Babcock:I simply got a letter from Bowen, saying I was appointed Assistant Director.
Weart:I see, And you accepted. So you served as administrative assistant?
Babcock:Well, thinking back now I canít recall that the duties of the Assistant Director were very strenuous, But a couple of years later, maybe it was Ď61, it was changed to read Associate Director. I did perhaps have a few more formal duties.
Weart:I would think all of this would have given you reason to hope that you would in fact become the next director.
Babcock:Well, it made me apprehensive. I was torn between two points of view, of course. In some respects, I looked with great disinterest at the idea of being Director. I knew that it would mean giving up all my own science, and getting into this kind of activity that Bowen had been doing, which really in itself doesnít have any appeal. But, anyhow, in 1963, Caryl Haskins was out here, President of the Carnegie Institution.
Caryl Haskins said that he had been around and talked to all the staff, and he assured me that every one of them was in favor of my appointment, Looking back on it, Iím surprised at that statement, But thatís what he said, I thought this over at some length, and I must admit, I found many elements of it that were not attractive, However, by 1964, when this appointment was to start, there was a new element in the picture. You see, when Haskins became President of the Carnegie Institution — I think this was about Ď61 — he replaced Vannevar Bush, and Haskins appointed a new Executive Officer, Ed Ackerman, of the Carnegie Institution.
And together they undertook a survey of what the Institution had done in the past and what it should do in the future, what should be the new aims and goals and so forth, This, Iím sure, was Haskins idea, but Ackerman expedited it and did a lot of the work, And he was pretty good at surveying opinions and coming up with a prospectus or whatever. Well, all the directors and most if not all the staff members were solicited, in this way, as to what their opinions were about changes for the Institution, What should the goals be? What should the Institution do? And among the opinions expressed were some that the Observatories ought to make a big new advance, and needed a big new telescope, and that it should be in the Southern Hemisphere.00: 00::See Appendix
Weart:Where did this idea come from?
Babcock:It was in part a revival of one of Haleís earliest proposals, dating from 1903. A letter from one of our staff members, Olin Wilson, was instrumental in this revival. And incidentally, another man engaged in this planning work was Merle Tuve, who was director of DTM at that time. In fact, the correspondence was between Merle Tuve and Olin Wilson, and copies went to Carl Haskins,
Weart:I guess those must be in the DTM files, in Tuveís papers.
Babcock:I have a lot of the correspondence related to all this.
Weart:Thatís very interesting. Thatís one of the things I was going to ask you about, your correspondence, Weíll get into that, but go on, please.
Babcock:Well, Olin was one who wrote a rather specific proposal, addressed to Tuve, saying he thought the Institution should build a major observatory in the Southern Hemisphere, I think that Bowen backed this up; Bowen must have been quite strong on it, And probably other staff members.
Weart:You werenít consulted at that time?
Babcock:Well, yes, I was given one of these circular letters. I have forgotten exactly what my own reply was to it. In any event, the idea of the Southern Observatory caught on. The trustees were given some sort of condensed output from this committee back there that was working on all these things, and it was adopted, The idea was adopted by the trustees, with Caryl Haskins, that the Observatories should think seriously about this, and should undertake a site survey with the idea that the trustees might provide major new funding for such a project.
Weart:Now, letís see, this was about the same time as AURA was being set up? Were these independent of one another?
Babcock:They were quite independents AURA had been set up by this time, and Kitt Peak was probably operating, at least in a small way, But Iím talking really about l96l62, getting into Ď63,
Weart:This was an independent idea of going to the Southern Hemispheres
Babcock:It ws the revival of part of the 1903 proposal, An advisory committee consisting of Lewis Boss, W.W. Campbell, and G.E. Hale had made 18::Department of Terrestrial Magnetism of the Carnegie Institution of Washington, 19::Associated Universities for Research in Astronomy, contracting organization for Kitt Peak and, later Cerro Tololo. recommendations to the Carnegie Institution for facilities and research in astronomy. One of the proposals then was a 60-inch telescope in the Southern Hemisphere. But they postponed it and decided instead to put the solar observatory on Mt. Wilson. Letís say that by 1964, when I was offered the directorship here, it was clear that at the very least, we were going in for an important site survey in the Southern Hemisphere, with the idea that we might be building a major telescope. This presented me with a tremendously attractive opportunity. Even as an undergraduate at Cal Tech, I had taken several courses in engineering—applied mechanics, theory of structures, materials and processes — in the hope that this background might be useful in the design of a telescope.
Weart:You had in fact already gone to Chile by the time you became Director.
Babcock:Yes. In Ď63 I went down and spent six weeks in Chile. In early Ď64 I went to Australia and New Zealand on the same job.
Weart:So all this helped convince you it would be a good idea to become the Director?
Babcock:I have to say that the prospect of building a new observatory, with a major new telescope, was such an attractive and challenging idea that I couldnít turn it down. It had some considerable appeal.
Weart:Has this been one of your main aims as Director? What have been your general aims as Director? Have these changed over the years?
Babcock:My aims as Director have been, first of all, to operate Palomar and Mt. Wilson as effectively as possible; to advance the auxiliary instrumentation, with the hope of keeping up with current technology — and incidentally, we had this project, really initiated by Bowen, to build the 60-inch at Palomar.
Weart:yes, I wanted to ask about that also.
Babcock:— and then at the same time, here was this big challenge of a Southern Hemisphere observatory. These were elements in the picture, And wisely or not, thatís what I got into. Iíve often thought since then, with hindsight, how much better it would have been had we got started a little earlier with the Southern Hemisphere project. Even two years earlier would have made a tremendous difference. We were just a little bit late, in comparison with AURA and ESO; this probably contributed to some difficulties, We still were able to bring things off, but a two year head-start would have been a tremendous gain.
Weart:I want to get back to these, I definitely want to get back to the 60-inch and Las Campanas — but first, your general trend as Director. You mentioned instruments, support apparatus. You have a long history here of doing support apparatus, instruments and so on. Has that been a particular interest of yours? Or has your particular interest been building the telescopes?
Babcock:Sure, I had an interest in support apparatus. Iím thinking of things like the photoelectric guider, and the exposure meter, things like this have always interested me, But Iíd hoped, of course, that others would bring along these things as needed, More importantly, though, things like improvements, basic improvements in spectrographs, where you have things like star-sky chopping, in which you can substract the sky spectrum, This is something that I was greatly interested in in the 1960ís. If Iíd had time, I think I could have developed it effectively.
Weart:If you hadnít been Director here.
Babcock:— much earlier, if I hadnít been Director. I tried to point out the opportunities here, and depended on the other staff members to pick up the ball and bring these things along. This wasnít good enough. There was altogether too much delay; people were too busy using the equipment they already had. As a result, we were a little behind the times in coming along with really effective spectrographs and photometers, things to compete with the Wampler machine and the like. We have them now, But we didnít get them as soon as we might have done. Westphal was of course really instrumental in getting us up-to-date there. And now we have other developments in that line coming along. Shectman has one of the possibilities. So I think on that score, of developing effective and current auxiliary instruments, we lagged. In part this was due to the difficulty in getting the money and finding the talent to bring along these sophisticated instruments.
Weart:I see. As you say, itís almost a matter that the staff wants to observe, so you practically have to hire somebody, some young fellow, to do it — in a sense.
Babcock:Well, yes. But as time has gone on here, in the last 20 years, itís more and more difficult to support a little group of experts on the observatory budget, people who are not professional astronomers but letís say talented designers. More and More, we find itís almost impossible to support such people. Instead, you have to get your research done by individual grant, and then hope the astronomer who gets the grant can get a talented assistant, and then he can develop his instrument perhaps, But the observatory-wide obligation gets down-graded, This is serious.
Weart:I see, because of the new way of funding things.
Weart:I see. Now, Iím also curious; during your period as Director, what have your relations with Carnegie been like? Mainly your relations with Caryl Haskins, with Abelson was there another in between?
Babcock:No, Bush was followed by Haskins and then Abelson, beginning about 1970. Iíve always had the most cordial relationship with Haskins. Heís a topnotch scientist in the biological field, a man of vast breadth and great perspective. He hasnít been very close to Observatory operation, But I had excellent relationships with Ed Ackerman, the Executive Officer of the Institution, and when the occasion arose, with Haskins, Iíd go to the annual meeting (Carnegie Institution) and Iíd see Haskins two or three times a year when he might visit out here in Pasadena. With Abelson, itís been a little different. He is the first President of Carnegie to take that job after having been a Director of a department; he moved up from within. Well, this is all pretty recent, and I probably shouldnít get into that one too much. He stepped into that position at a very difficult time, and it hasnít been easy for him.
Weart:What Iím mainly interested in is not personalities, but anything that may show how the organization, the institution, works — how the philosophy or administrative setup may change.
Babcock:The Institution of course has a board of trustees, who have been largely insulated from the research departments. Any contact is through the office of the President. Trustees up here (holding hand high up), and any communication goes through the President. And this has been, I think, not a very good policy. There have been efforts to open things up a little bit lately, and these have worked to some degree. The President of the Carnegie Institution really does a minimum of directing the activities of the departments. He decides the budget ceiling. He looks at the budgets that come in, passes them along to the trustees, and the trustees at their annual meeting approve the budgets. There are occasional consultations with the Directors. The President meets about four times per year with the Executive Committee of the Trustees. Thereís an annual report that comes through, and occasional policy memos and such. But really, the Institution has a great deal of inertia, And there is not as much cognizance by the trustees of what is going on as there might be. I see the other directors just once a year at the annual meeting in May, and thatís it. I see some of the trustees too, but not at their business meeting; just socially. So the President expects the Director to run his department, really gives him a lot of authority and backup, and thatís about it.
Weart:So youíve been quite independent.
Babcock:Relatively independent, yes. Relationships with the Carnegie Institution have been very different from those with Cal Tech.
Weart:So the only problem comes then in setting the budgetary ceilings and then figuring how to raise funds, that sort of thing?
Babcock:Coping with the rising costs of research in these times is a very difficult problem. The budget ceiling is set by the president, after reviewing what the income of the Institutionís endowment is each year. The Institution has had to relax its older policy against acceptance of federal funds. Research grants to individual staff members have been common for several years now. We see increasing interest on the part of some of the trustees, who find time to come here and talk to us. Weíre very glad of this, and they seem to enjoy it. We have one Carnegie trustee who is an active research astronomer. This is Charles H. Townes. We are very glad indeed of his presence.
Babcock:At Berkeley, of course, but he goes to Las Campanas for observing.
Weart:Right, he can be a communications source.
Babcock:Yes, This is great.
Weart:OK, thereís more I could ask you about that, but Iím also curious about the Cal Tech side. How does that budgetary process work, and how does that relationship function?
Babcock:When Harold Brown was President of Cal Tech, he delegated almost all the operational responsibilities to the provost, Bob Christy. Again there is a budget ceiling that is determined higher up and is essentially delivered once a year.
Weart:Not much you can do about that?
Babcock:Not very much I can do about that. Occasionally, though, Cal Tech has been able to come through with some modest supplement on request. By arrangement, the Associate Director really drafts most of the budget for Palomar this is Bev Oke. Pretty much itís cut and dried, I mean, you have certain expenses that you have to meet, you have to for utilities, food, wages and what not. Thereís very little left, if anything, for research expenses. Almost entirely, research has to be done on the basis of federal grants that staff members on the Cal Tech side achieve.
Weart:This has changed a good bit in the last ten years, I suppose.
Babcock:Itís gone almost fully in that direction, to the extent that half to two-thirds of professional salaries are now charged to grants, for Cal Tech, But not for Carnegie, where the professional salaries come 100 percent from the Institution.
Weart:I see. Has there been any pressure to change that?
Babcock:There have been questions, But also the feeling has been expressed that the trustees wouldnít want to change it. It would be difficult, (A major policy change occurred in 1979),
Weart:I see. This must mean, in a way, that Cal Tech science has grown stronger relative to the Carnegie side, because thereís more money on that side.
Babcock:The Carnegie potential for astronomy has grown tremendously with the completion of Las Campanas. Also, while Cal Tech gets more from grants, the money that Cal Tech puts in from its general budget is a good deal less than the money that Carnegie contributes, Carnegieís funds for Mt. Wilson and for Las Campanas are much greater than those that Cal Tech puts in to run Palomer. On the other hand, the relationship that I feel with the Cal Tech administration is not nearly as close as it might be. I have no contact with the Cal Tech trustees, And I feel that the Observatories really are not properly regarded. Here we have a scientific organization, with 20 staff members, thatís operated jointly by these two sponsoring institutions. Well, the fact is that Cal Tech goes on about its business, with very little recognition of the Observatories as such. Iím being utterly frank here, but I feel that things have gone too much in this direction.
Weart:I can understand, From the Cal Tech side as you say, they see it as a big agglomeration of things, and I suppose Carnegie can give you more attention.
Babcock:Yes, on the Carnegie side itís one department, one of five, Itís crystal clear.
Weart:Thatís interesting, it makes sense. Has it always been this way? Has this changed very much or was it that way even under Bowen?
Babcock:Well, certainly it has not always been this way, You see, at the start in 1948, the astronomical staff was altogether here, Cal Tech hadnít yet appointed anybody until, well, about Ď48 they appointed (Jesse) Greenstein.
Weart:So it was much easier to see this place as a separate unit.
Babcock:The Observatories were readily identifiable. When things were just growing at Cal Tech with the initial appointments, Bowen was able to keep it quite clear. There was just no doubt about it. I mean, if Osterbrock and Code were appointed to the Observatory staff, they had offices in Robinson, along with Greenstein — well OK, they were Observatory staff members, and they had some teaching duties. But as time went on, and you developed a bigger group at Cal Tech, and some of them were working in planetary or infra-red astronomy or they werenít integrated into the group. They regarded themselves as physicists, or geologists maybe, and so the identity was hard to maintain.
Weart:Did any of these things change significantly when there was this revision of the agreement (l969-70)? Did that revision make a real difference in relationships?
Babcock:Perhaps the principal difference was that there was an Associate Director appointed, and he was given a lot of responsibility for Palomar, The revision was largely dictated by Bacher.
Babcock:In any event, it was not all smooth going.
Weart:You were, so to speak, representing Carnegie, and Bacher was representing Cal Tech?
Babcock:No, I didnít think of it in that way. I was the Director and I reported equally to the president of Cal Tech and to the president of the Carnegie Institution.
Weart:Well, then, who represented Carnegie?
Babcock:Iím sure at first there were some talks between Bacher and Caryl Haskins. But when it boiled down to discussion of specifics, it amounted to Bacher asking me to come down to his office, and he would tell me how it was going to be.
Weart:What gave him the power to do this?
Babcock:Well, thatís a good question. I think it was, possibly, that Caryl Haskins felt that the revision was not of overwhelming importance, and that it could be settled largely in Pasadena.
Weart:Have you ever had comparable pressure from the Carnegie side, when Abelson or whoever was saying, ďThis is the way weíll do things?Ē
Babcock:In connection with funding, here and there, yes, Abelson preferred to maintain rather remote from the actual problems, from the actual administration, letís say, Iím thinking primarily of the construction job at Las Campanas, and meeting the unforeseen demands of all the increases due to inflation, increase in shipping rates, fuel costs, price of steel, political disturbances in Chile, what have you — these things hit us, and back in Washington they didnít want to listen. Theyíd say, ďWell, you made an estimate in 1963 as to what it would cost. How can you come in now with all these extra requests?Ē You know.
Weart:They say having two bosses is great when thereís a lot of money, and itís terrible when thereís not enough.
Babcock:I donít think itís ever any good. (Laughter) Oh, there have been some problems with the Carnegie administration, but as a rule, when people involved would come here, or go to Chile and get acquainted with the problems, then suddenly theyíd become much more sympathet ic, and usually an answer would be found,
Weart:Right, Reminds me of what I was reading the other day Iím going out to interview Jefferies next I was reading about building the Mauna Kea observatory, They really had problems, because of the altitude, They said that the bosses couldnít understand why the workmen werenít getting Babcock 82 anything done, until theyíd been to the mountaintop themselves theyíd practically faint and then they could understand what the problems were. OK, letís switch back now. I want to ask you about two things, one is Las Campanas but first, to get it out of the way. Iím curious about the 60-inch and how that came about. You had funds from NSF, NASA, Cal Tech, Carnegie, and from the Oscar Mayer family. How did this all develop, as you see it?
Babcock:That was quite a package. The plan was pretty well developed before I became Director. It was discussed many times in the Observatory Committee. In general the need for a 60-inch, or such a telescope, at Palomar, was well recognized. It would be very useful. It would give the students opportunity to work with a telescope there in good skies. Many things could be done with a 60-inch that donít have to be done on the 200-inch, thus permitting the 200-inch to be more effective. So it was a good idea, and there was no doubt that Palomar was a sufficiently good site to justify a new 60-inch telescope. On the other hand, there wasnít much money available. There wasnít much money available, but various people got interested, and on the Cal Tech side they interested the Mayer family in funding the dome.
Weart:This was the Cal Tech people, Who specifically?
Babcock:I think Jesse Greenstein had quite a hand in that. To keep the expense down, a steel dome of the same size and design as that of the 48-inch Schmidt was adopted. The rest of the building was kept within a budgetary limit. So Cal Tech assumed responsibility for funding the building. NASA had made available a quartz disc, and that was contributed. And then Carnegie Institution went to NSF for funds to build the rest of the telescope. Bowen developed the optical design. Bruce Rule was designer of the mounting and mechanical parts, and Bob Hoggon did the structural engineering.
Weart:All this had started by the time you became Director?
Babcock:It was in a stage of serious planning. The design was basically complete and construction was started in 1966. At the same time funding efforts and site surveys were underway for Carnegieís southern hemisphere observatory (CARSO).
Weart:How did Carnegie feel about going to NSF and NASA for funds?
Babcock:There didnít seem to be any objection there. It was clear that the telescope was a well-conceived idea for Palomar. One reason Cal Tech didnít want to go to NSF was that they had just recently requested a large amount of money for Owens Valley radio astronomy, and they thought it would be very poor form to come in almost at the same time with a big request for an optical telescope. Bruce Rule of course was our chief engineer, and quite a talented telescope designer. At this time Bowen had designed the optics for the telescope. Again he had a very good idea. It is a Ritchey-Chretien system, which has a wide field. Bowen achieved a flat field by having a secondary mirror thatís half the diameter of the primary. So it is a wide-field telescope, and the plates donít have to be bent. Bruce Rule took over the mechanical design of the telescope and made some initial cost estimates. We tried to keep costs down, keep it economical. We wanted to present a request that NSF could meet, that wouldnít seem too excessive. So we presented the proposal, and after a while it was approved.
Weart:Presented it through the trustees of Carnegie?
Babcock:Thatís right, through the presidentís office of Carnegie. And Bruce Rule of course had primary engineering responsibility. We had an agreement to do the optical work here in our own shop, and so the quartz disc from NASA was brought here, Cal Tech and Carnegie jointly funded the grinding machine for the mirror.
Weart:A new grinding machine, I see.
Babcock:The optical work was done primarily by our chief opticians, Floyd Day.
Weart:Floyd Day, right, I remember him.
Babcock:Day worked under pretty close supervision by Bowen, Although Bowen was nominally retired he gave almost daily supervision on this. The telescope and the building were erected. Certainly the time required was considerable, I think it wasnít until Ď69 that we finally had it erected and operating, and dedicated it. We had a program at Palomar, with Mr. Oscar Mayer, representatives of NSF, and some of the trustees. The telescope had to be built on a restricted budget, but we wanted to make it as up-to-date as possible, not only optically, but electronically. We learned much about computer control of telescopes, with that one, and this was of great benefit later with respect to the duPont telescope. The computer software was very expensive.
Weart:Is that where the problem with the Astro-electronics laboratory came up, primarily with the 60-inch?
Babcock:There was a serious problem, in that the estimates were always far short of the mark, This is one of the penalties for using a rapidly developing technology, The software development went on and on at great expense, In some respects, the Palomar 60-inch telescope is not as convenient as it should be. Funds are limited, so that we still donít have quite the level of auxiliary instrumentation on it that weíd like to see. Nevertheless itís in great demand, and itís used practically all the time, and it produces many good results.
Weart:It does get used.
Babcock:It not only gets used, its in great demand. But it was not a very good thing that the 60-inch had to be designed and then constructed while at the same time Bruce Rule was heavily engaged in producing a series of estimates for CARSO.
Weart:What do you mean, backup for fund-raising efforts?
Babcock:During these years, Carnegie was trying to raise funds to build a 200-inch telescope in the South.
Weart:So, doing studies for the 200-inch, you mean.
Weart:Not directly in support of fund-raising, but to provideó
Babcock:Estimates of what a Southern Hemisphere observatory would cost if equipped with various combinations of telescopes.
Weart:Why donít we talk about Las Campanas now? You mentioned about how it got started, and about the site surveys, Ď64 through Ď66, and these engineering studies that were done under Bruce Rule. Iíve seen reports and so on that there was hope of using the proven Palomar design. For the 200-inch, I suppose, the idea was the same idea as Palomar, oil pad bearings, pretty much taking over the design.
Babcock:Oil pad bearings and the Serrurier truss. But to go to quartz optics, which would be a big change in itself. It meant redesigning the mirror support and all that. And of course more modern control systems.
Weart:I see. But basically, an updated Palomar?
Babcock:An improved and updated Hale Telescope.
Weart:So it would be cheaper.
Babcock:So it would be the best possible, and least expensive, 200-inch, The same dome size, for example, and the same horse-shoe mounting, yes.
Weart:I see, Let me run down the basics and then weíll go back over it. In 1969, there was a gift from Henrietta Swope for site development and a 40-inch telescope; 1968 was the decision to locate on Las Campanas; 1970, the gift from Mr. and Mrs. Crawford Greenewalt for the duPont telescope, and the Carnegie Institution (chipped in) agreed to augment the gift and to proceed with construction of the observatory. Then last year, the optics were installed, and as you say youíre getting photographs with it now. So maybe we can go back, and pick up how you saw all this develop.
We had a pretty extensive site survey effort, As I say, I first spent six weeks in Chile; I had very good cooperation from Nick Mayall (KPNO director), Jurgen Stock and other AURA people who were at Cerro Tololo already at that time. One thing that we had done already was to develop field equipment for measuring the seeing in a quantitative way, with a photoelectric device on a portable 8Ē telescope. We put a great deal of emphasis on getting a site with the best possible seeing, as well as a reasonable percentage of clear skies and other desirable qualities. So we used our field equipment at Tololo, and on two or three adjacent peaks which were on the AURA property Iím speaking of Morado, Pachon and some other mountains. Also I made two trips to Australia and New Zealand. We had a site survey field man over in Australia for nine months, using one of the same seeing monitors.
But it was clear that Chile had the edge, and we soon gave up on Australia. For some years, from Ď63 up through Ď67, our feeling was that if we located in Chile weíd quite possibly be on some mountain to be purchased or leased from AURA, whose property included four or five peaks. At the same time, we also were checking out other mountains in that same general region of Chile. Over the years, it became clear that AURA and CIW operated in different ways. After all, AURA had government money and a very generous budget. They were a combination of 12 universities and a big board of directors, whereas CIW has one department to do astronomy. I found it difficult to get decisions from this big AURA board. It became clear that AURA was reluctant to sell CIW land for an observatory.
They might lease land, but only a few acres at most. More importantly, our studies showed that the AURA sites would suffer light pollution from proximity to the cities of La Serena and Coquimbo; that potential large mining developments were too close, and that development of adequate water on Morado would be very costly for CIW. We had been checking out other sites. Among these was Las Campanas, which, right from the start, had a lot of appeal, except it looked as if there might be little available water. Also, during the same period of years, beginning around Ď65, CIW had been engaged in an effort to raise funds from the Ford Foundation to build the proposed 200-inch.
Weart:I didnít know that, Who is ďweĒ, by the way?
CIW, Carnegie Institution of Washington. I should say at the outset, however, that in the summer of 1963 Caryl Haskins came out to Pasadena and there was a very important meeting with Lee Dubridge at which Ackerman, Bowen, Bacher and I were present. Haskins invited Cal Tech to join with the Carnegie Institution in establishing a major new observatory in the Southern Hemisphere with a 200-inch telescope modelled on the Hale Telescope at Palomar. Lee Dubridge responded that he appreciated the invitation, but Cal Tech had just engaged in a big campaign to expand its campus and to construct a number of buildings; financially they were unable to join the effort, But Cal Tech would be glad to look on this new development as an important addition to the Mt. Wilson-Palomar complex, as a much needed Southern observatory and gave us every good wish. But this left the funding and the financial responsibility entirely in Carnegieís hands. The Ford Foundation was called upon, and we had extensive discussions and visits with the Ford staff people.
Everything went quite well over a period of about a year and a half. I went with Carl Borgman to Chile and showed him the possibilities there. While it was not at all clear that Ford could come in with all that was needed for a 200-inch,of course. Carnegie was going to put in a substantial amount, but the balance of the funding was not clear. Nevertheless, there was a pretty good expectation that Ford could come in to the tune of on the order of 10 million dollars, something really very substantial. The situation from this point on gets to be very sensitive, and I have a reluctance even today to talk about it for tape, The whole story is known to just a very few people, including Caryl Haskins, Julius Stratton and myself. I think itís probably better left off of the tape. The result was that the Ford Foundation gave five million dollars to AURA for their telescope on Cerro Tololo, and nothing to Carnegie and that Carnegie Institution decided to procure Las Campanas, feeling that this was the best observatory site in Chile. In the meantime, it turned out that there was an adequate water supply at Las Campanas, whereas the Tololo water supply had to be augmented at great additional expense.
The result of all this is that at Las Campanas I think we have the best site in the Southern Hemisphere. It is good. It was readily adaptable to development; it was easy to put in a road; it has adequate water. Itís a ridge three miles long, on which there are any number of sites for telescopes. Thereís plenty of room. And it has, we believe, a higher percentage of clear nights a year, and possibly better seeing, that Tololo. (Tape recorder turned off briefly)
Weart:Maybe at another time weíll talk about some of these details under seal, But for right now, maybe you can go on and tell me something about some of these other later developments, the Swope gift and the gift of the Greenewalts and the other thing.
Babcock:Yes, In any event, Henrietta Swopeís gift was most timely, and it did permit us to proceed with some site development at Las Campanas, the water system, the road, and the 40-inch telescope.
Weart:How as that gift developed?
Babcock:She had long been a member of the staff here. She was aware of the various staff discussions about the Southern Observatory. She was tremendously interested in it. I heard about her gift when Haskins called up with the news.
Weart:She just volunteered it?
Babcock:She volunteered it, yes. In any event, the site survey work had been carried from Ď63 up to Ď68 or Ď69, and then by that time the decision was made that yes, we would at least develop Cerro Las Campanas as an observatory site, and we would install the 40-inch telescope. So we did that, with the help of a contractor in Chile, and we had — the Boller and Chivens (Company) Division of Perkin Elmer Corporation produce the 40-inch telescope. The optical design was due to Bowen. We had to conclude that we probably could not build a 200-inch there, but we kept active on fundraising efforts, and then the situation was marked by the gift from the Greenewalts right about the end of Ď69 I believe that it was, They said they would make this gift. I think 1-1/2 million dollars, But with the provision that it would be used almost immediately, without waiting to augment the funds sufficiently to build a 200-inch. They wanted the funds used to build a suitable telescope of the 90-inch to 100-inch class.
Weart:Why did they make this provision?
Babcock:I think they felt that if the Institution waited, and tried to get more funds to build a 200-inch, some indefinite time would elapse, and they didnít want to see that. They wanted to see action.
Weart:I see. It might be a long time. How did the Greenewalts gift come? This is one of the most important gifts that has been made in recent years. Iím curious as to how that gift came about.
Babcock:Crawford Greenwalt of course had been a Carnegie trustee for a long time. And his wife was a prominent member of the duPont family, the daughter of Irenee dupont, who had some interest in science. It even seems that, at the Greenewalt family headquarters outside of Wilmington (Delaware), thereís a small observatory. They have a telescope of about 20-inch aperture. Nick Mayall has seen it. Anyway, Crawford Greenewalt has always been very much interested in our big telescopes, and it turned out that Mrs. Greenewalt was also interested. Sheís a most unusual person. I donít really know her to any extent, but sheís been a kind of an angel, in the financial sense, you see. Just because she wants to do something like this.
Weart:Tell me, Iím very curious the whole idea of fundraising and where the funds come from, for astronomy. I think is very important. Have you played much role yourself in the fundraising? Have you approached people for funds?
Babcock:Beginning in Ď63, and for several years, Ed Ackerman and I collaborated, at least in preparing all the documentation putting together the prospectuses, developing plans that we thought would appeal. I would say that Caryl Haskins and Ed Ackerman headed the fundraising drive from the Washington office. Ackerman had files on various foundations and so forth. He and Caryl Haskins checked out the Johnson Foundation, and they started the contact with the Ford Foundation. I went with Ackerman to the New York office of the Ford Foundation, and we had a very important interview there.
Weart:You must have met the Greenewalts before the gift was given and so forth.
Babcock:Yes, The Greenewalts made a special visit to headquarters in Washington on one occasion; Sandage and I were both there and both talked to Mrs. Greenewalt without knowing quite what was in the wind, But this gift resulted. In addition, there were other combinations proposed. There was serious effort given to a joint project with the Canadians, who were serious about a big telescope. Ed Ackerman and I made, I think, three trips to Toronto and Ottawa. We talked to the Minister of Finance or whatever he is in the Canadian government about this, and we had something pretty near the surface there for awhile, about a joint project with the Canadians. We discussed a possible joint project with the Australians. But of course, they couldnít very well go outside of Australia, so their input stayed there. Then there was, at a later date, a serious discussion with the British. Ed Ackerman and I went to London to talk to the head of the Science Research Council. I think we had two meetings there, and again, it was a proposal that the British would join with the Carnegie Institution on this big telescope.
Weart:Did you try the French also?
Babcock:No, we didnít try the French. (Laughter)
Weart:You donít mind that you didnít, I understand. Why didnít any of these government things well, I understand the Australians. But was it particularly because it was difficult for a government to deal with a private institution, do you suppose?
Babcock:Oh, partly that, In the case of Canada, the eastern Canadian astronomers and the western Canadian astronomers just couldnít seem to get together on anything. It didnít work. Although at times, it seemed to be pretty serious, and we had many discussions. With the British, it was more of a question, and perhaps never came very close to fruition. Nevertheless, we had some pretty serious talks there. I think those discussions, with the Canadians and the British, occurred while we still had the Ford Foundation on our side of the picture, and it might have been possible to put together a pretty good package.
Weart:I see, so the thing was that that sort of fell through, and then the Greenewalt thing came along a little too late for the Ė
Babcock:The Greenewalt gift came after the other support had weakened. The Carnegie Institution, however, had purchased the Las Campanas property and, with Henrietta Swopťís gift, the 40-inch telescope was assured and site development was under way.
Babcock:And when AURA had the Ford Foundationís five million dollars. But the Greenewalts came through, and this was great, of course.
Weart:And it was a little late at that point to get together with the British and whatever, I see. Tell me again, more generally, about fundraising. Had you also approached a number of other people for private funds, for smaller things, whatever?
Babcock:In general, no, I havenít personally really taken very much of a hand in fundraising, as that was handled by the Office of Administration in Washington. Oh, I made some presentations to Carnegie trustees, for example, But thatís a little bit different.
Weart:Even so, itís a similar thing. I guess what I really am interested in is, outside of the government, when youíre approaching private people, what kind of people are interested in supporting astronomy? And why are they interested in supporting astronomy?
Babcock:Itís hard to say, Possibly one can say itís because of some past contact, some feeling of real interest, that you can never be aware of much beforehand. A few years ago, a Mr. Morgenroth in Portland, Oregon died, and we found out, in his will he left $35,000 to the Mt. Wilson Observatory, Nobody here ever heard of him, He probably visited here once, and got some emotional tie-up with the place, Some of these things are just unpredictable. Now, of course, itís been proposed that we should be systematic, that we would get a computer checkout going all of the subscribers to SKY AND TELESCOPE, cross-match that will all the people who earn more than $100,000 a year, see what you can turn up. But in this job, with its heavy operational responsibilities, I just havenít had the time to start some new undertaking like that.
Weart:In general, why do you think people support astronomy? What is there about astronomy that attracts people like the Greenewalts or Carnegie trustees or Ford Foundation, to astronomy, anyway?
Babcock:I canít come up with much, except I suppose rather trite ideas, that itís a subject of great intellectual interest to a lot of people. People just like to know some of the answers about whatís out there, and some of them are willing to give it hard support. Maybe they find something of glamor in big telescopes and what they can do. Maybe they see astronomers working all their lives on some of these problems. Maybe they read about some of the results, and find it kind of interesting. No, I donít know in,say, Mrs. Greenewaltís case, except that she was aware of course her father had some interest in science, and the family was interested enough to procure a telescope and set it up there on the grounds. William Randolph Hearst, back in the thirties, bought a telescope that was installed at San Simeon. Well, he might have been a candidate for a giver, but the timing was wrong.
Weart:I see. What else about Las Campanas? The actual building of it is there something to be said about the time between the Greenewalt gift and now?
Babcock:Well, in that interval a lot has been done at Las Campanas, of course. The Observatory has been developed, and the road, an adequate water system, a power system. Weíve had our hands very full, first with getting the telescope engineered. One of Greenewalts provisos was that the telescope should be designed by the staff, so we got Bruce Rule and provided him with a group of engineers, and they designed the basic telescope. Bowen with Art Vaughnís help, designed the optics. We ordered the mirror blanks and arranged for all of the optical work. Once it was designed, we turned over the contract for the mounting to Boller and Chivens and L and F industries, and they built the telescope and the steel dome. All the parts of the building in Chile were erected by a Chilean contractor with help from our own CIW employees. This took a lot of doing. It was all steered from here, and was quite an activity. Of course we had to ship supplies, parts, components, practically everything from here. The only thing we bought in Chile was the cement and so on.
Weart:Aside from the obvious inconveniences have there been any particular developments because of the very complex political history that Chile has had?
Babcock:These reflected on our ability to get the work done, yes. But I would say that beginning way back in í63. Weíve had excellent support from the presidents of Chile, the various presidents that have come along, and many government officials. The support of the University of Chile was important.
Weart:Did you have difficulties, either in Chile or in this country, because at one point you were dealing with a Communist regime and at another point you were dealing with a fascist regime or whatever people call it? Has either one of these caused you severe problems?
No, President Eduardo Frey (1964-1970) was especially helpful to us. There has not been a fascist regime. In dealing with the various administrations, we havenít had any severe problems with the regimes as such. The severe problem came about during the later years of Allende administration (1972-73) when Chile was in chaos and the country was essentially out of control. The finances were wild, and there were breakdowns all over the place. People were striking against the government. The mines were on strike; transportation people were on strike and so trucks were not running.
It was very hard for us to get our shipments off-loaded in Chile and trucked to the mountain, and difficult for us to feed our own employees, We had to send shipments of food from California to feed our people, and we had to send clothes down, work clothes, for our employees, Inflation was at 300 percent annually. There was little traffic on the highways because fuel was becoming almost obtainable. If this had gotten much worse, and if it had gone on another six months, we might have had to stop construction. But we kept at it, and after a while things improved, after the military took over by popular request— then there was no more nonsense, and things were certainly under pretty good control. And at least we had verbal support even from Allende (1970-1973) as well as from the other administrations.
Weart:I see. Well — weíre getting near the end. I have a few spare questions put together. One, the 1967 article you wrote in SCIENCE, urging a big telescope in the Southern Hemisphere. This is one of the few articles youíve written outside the technical journals. I wonder why you wrote this article at that time?
Babcock:I havenít thought about it for years, I donít know that I could come up with an answer. It might have been related to some of my feelings about our unsuccessful fund-raising efforts, but I donít know. Iíd have to read the article again.
Weart:One thing that I did notice in that was that you felt that the distribution of funds between space and ground-based astronomy was inequitable. I was curious whether you were expressing an opinion that was generally floating around here?
Babcock:I think it was essentially my own opinion, I donít have any great qualms about spending large amounts of money on space astronomy, but I think that there should be enough perspective so that ground-based astronomy gets adequate attention too. I felt that perhaps this was not the case. Really, Iíd forgotten about that article.
Weart:What has been your attitude towards people who popularize science, popularize astronomy? What do you feel about that kind of work?
Babcock:Well, if they have their facts more or less straight, I think itís fine. As long as they do a reasonably good job on it. Of course, thereís been a lot of fringe people who grind their own axes, or who get off onto pseudoscience and so forth, I mean, thereíve been people like Adamsky and Father Ricard, for example. But I donít think youíre referring to those people at all.
Weart:No, Iím referring to astronomers who write articles in SCIENTIFIC AMERICAN or Ė
Babcock:oh well, thatís fine, I attempted one myself, although I was never very proud of that article, (But writing it stimulated my thinking)
Weart:Are you much concerned about the publicís attitude towards astronomy? You mentioned how you noticed an increase in attention after Sputnik. Is this of much concern to you, what the public thinks about astronomy?
Babcock:Yes, I think the publicís attitude is certainly important, If it werenít for that, astronomy would probably have no support or very little indeed. And after all, it seems to me that work that astronomers do is finding out new things, and the new findings ought to be published, made available, presumably, some at least in the public are going to be interested in this, I think the Observatories have some obligation to see that some of their results, the kind with more popular appeal, do in fact get distributed.
Weart:Thatís why you have this committee that you mentioned, for press releases.
Babcock:That, for one thing, But more specifically, thatís why we have available our catalog full of photographs, that we supply to the public for incidental demands, and also for educational purposes to schools and the like, I think in past years weíve been perhaps the main supplier of astronomical photographs and slides and prints for purposes like that.
Weart:I see, this has been deliberately for these purposes not just because you just happen to have them, but deliberately as a policy?
Babcock:Oh yes, itís a deliberate policy, and it takes a real effort. It takes some of our budget as well as considerable time to provide these services. Look at the Hale Observatories Catalog of Photographs, for example.
Weart:I see. You were an astronomer back in the late thirties; youíre an astronomer now. Do you feel that the public attitude toward astronomy is very different from what it was then?
Babcock:Well, yes, I think to some extent it is different. Of course, my opinion is colored by the fact that I was here much of the time, in Pasadena, while the 200-inch project was getting developed. And locally of course it got a great amount of attention in the media.
Babcock:In other parts of the United States the 200-inch didnít cut so much of a figure. But around here, the 200-inch project and ground-based astronomy in general attracted a fair amount of public interest. There were lots of amateur astronomers also. I do have the feeling nowadays that with all the emphasis on reporting of space activities, and all the science fiction that is built around space activities, perhaps the public perspective has been partly lost, mean, thereís possibly a great deal of confusion as to what space is, as related to astronomy. Now, for a few of the more serious readers, of course, know what the red shift is and something about what astronomers are working on. But too many people, I think, have the idea that old astronomy is now out-dated, that everything of importance is done from these rockets. So perhaps in general thereís a lot more interest, but itís not very well focused. Science fiction may have blurred the distinction between the real and imaginary world.
Weart:Speaking of science fiction and so forth, do you have any strong opinions on extraterrestrial intelligence and the search for it?
Babcock:I donít have any very strong opinions, except perhaps the following, I think itís too early for the country to spend or commit large amounts of money to some tremendous project OZMA, or whatever — to start in listening by building extremely large and expensive arrays. It seems to me that itís just too early. I mean, itís only 50 years ago that we began to realize what a galaxy is. And even less time since we knew how far away the galaxies are. Weíre learning very rapidly now a lot of interesting new information about galaxies, how theyíre made up of stars and dust and gas and how they evolve. Our information is still fragmentary. Itís still increasing very rapidly. And I just think that we should continue our scientific efforts to learn more about space and galaxies and what is out there— learn a lot more, before we start committing vast sums, letís say, to a Project OZMA. Maybe at some time, weíll reach a state of knowledge where that will be justified.
Weart:Thatís a good way of putting it. Iím curious also what feelings you may have about some of the current cosmological questions, for example about the question of whether or not the universe is open?
Babcock:Again, I think itís premature to try to answer that particular question, The evidence isnít all in yet, and there are some difficulties about interpreting the evolutionay changes in galaxies, It irks me a little bit that people have to jump in and stake their reputations on its being open or closed, maybe trying to get ahead of somebody else. Letís get the observations in and do the work, and the answer will come out.
Weart:What about Big Bang versus Steady State? Do you feel that that has been settled?
Babcock:Pretty much. It seems to me that one is safe now in adopting the Big Bang idea, as a pretty good working hypothesis, and letís really go along with that.
Weart:Was there ever a point at which you felt that Steady State was a strong contender?
Babcock:Oh, no, I donít think I ever got to the point where I felt it was a very strong contender. But all of that discussion was at the fore front when I was very heavily occupied with the Southern Hemisphere work. I read about it but I wasnít in deeply enough to feel terribly involved in this.
Weart:I see, I understand, it wasnít your main field, of course, anyway. Could you tell me, what are the main ways youíve spent your time out side of working hours? Outside of astronomy?
Babcock:I guess as a matter of fact, in the last ten years about the only recreation Iíve had has been a bit of sailing.
Weart:Around Santa Monica?
Babcock:Close to that, Redondo Beach. We do have a sailboat that we keep down there. I have felt the need of some kind of recreation, that is to get some separation from this demanding job, a total change, get away from the office. My wife and I, it turns out, both find some pleasure in sailing, and we have a son whoís now 15 who also enjoys it.
Weart:I see. Iím trying to get a picture of you as a full human being. Do you have any religious affiliation now?
Weart:Any strong convictions?
Babcock:No, I donít feel bound by any very strong religious convictions. I have a good deal of respect for what you might call the Christian ethic — but as for a personal strong view of religion, I donít have anything like that.
Weart:Whatís your feeling about this universe that youíve been studying so many years?
Babcock:Itís a fascinating physical world, and it has the universe as the large-scale end of things. Thereís a great deal to be found out. Itís amazing to me how rapidly we continue to learn, and how many new problems there are coming along, and Iím glad to get some little part in some of this activity, and to have a chance to learn a little more about aspects of it. But at the same time, you can look at things like plate-tectonics and some of these other concepts, theyíre fascinating too. So I enjoy doing a little reading on the side, on some of these other branches of science.
Weart:I see. To a certain extent, had things been different, you might have wound up as a geologist or whatever — and had just as much fun, I suppose.
Babcock:Well, thatís entirely possible.
Weart:Iíve run to the end of my pack of questions... (Brief discussion of other interviewees not transcribed)
Publications of the Astronomical Society of the Pacific 44 (1932), 323;46 (1934), 132, with H.D. Babcock 47 (1935), 321; 48 (1936), 206
 No. 498, October 1939. ďThe Rotation of the Andromedia Nebula.Ē
Astronomical Society of the Pacific
Radiation Laboratory at MIT
Radiation Laboratory at MIT Los Alamos, New Mexico
 Electronics 19 (1946), 120-22
 Office of Scientific Research and Development
Astrophysical Journal 105 (1947), lO5-l9, p. 119.
 See ďThe 34-Kilogauss Magnetic field of HD 215441,Ē Ap. J. 132 (1960), 521ó31.
See Journal of the Optical Society of America 41 (1951), 776-786, with Harold D. Babcock.
The solar tower telescope on Mt. Wilson; the Hale solar Laboratory in San Marino-SW.
i.e. Second mirror of the heliostat.
Ap. J. 133 (l96l), 572-87
 i.e. Ap. J. 121 (1954), 349-66, with H.D. Babcock.
 ďThe Paschen series of hydrogen lines in the spectrum of the solar chromospheres.Ē PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF THE PACIFIC 44 (1932), 323.
The tea takes place in the library of Robinson Lab, then the company goes across the way to a lecture room. There might be 20 to 50 attendees. — SW
One may find 30 or more astronomers at a long table in the back of the Athenaem dining room — SW
Department of Terrestrial Magnetism of the Carnegie Institution of Washington.
Associated Universities for Research in Astronomy, contracting organization for Kitt Peak and, later Cerro Tololo.
 European southern Observatory (also in Chile)
ďOptical Astronomy in rspective,Ē Science 156 (1987), 1317-22.
ďThe Magnetism of the Sun.Ē Vol. 202, No. 2 (1960), 52-62