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Interview of Guido Munch by David DeVorkin on 1977 July 7, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4789
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Early life in Mexico; Civil Engineering school, 1938, physics in Mexico; University of Mexico; study group; visitors from the United States, 1941; McDonald and Yerkes Observatories, 1942; work with Otto Struve; modern physics at University of Mexico; contact with Subrahmanyan Chandrasekhar; Solomon Lefshetz's influence on mathematics in Mexico; Yerkes courses and general atmosphere after 1944; Struve's administration; work with Chandrasekhar; postdoctoral work in Mexico; return to Yerkes, staff reorganization; research at Yerkes, including radiative transfer, stellar envelopes, and Jupiter (Gerhard Herzberg); Mt. Wilson and work there; Caltech position; general research in 1950s and 1960s; limitations of present day research; teaching at Caltech; National Aeronautics and Space Administration (NASA); decision to accept position in Germany; Caltech and Carnegie Institute of Technology; role of Kitt Peak Observatory in Federal Funding for Astronomy; reflections on past work. Also prominently mentioned are: Camilo Arguello, Wilhelm Heinrich Walter Baade, Jesse Leonard Greenstein, Robert Hutchins, Gerard Peter Kuiper, William Wilson Morgan, Luis Münch, Satero Prieto, Olin Chaddock Wilson; Hale Observatories, and Tonantzintla Observatory.
I know that you were born in Mexico in 1921, but I don’t know anything else about your family and your background. Who were your parents? What did they do?
My father, at present still living, is August Münch. He was born in Mexico, son of an American lady (United States American), and granddaughter of Johann August Sutter, of California—gold fame, and a German man. He never did anything professionally. He went to school in Germany because at that time his father thought that there was nothing else but the old country. But the First World War broke up his studies and he came back to Mexico, where carried diverse small business. My mother, Maria Paniagua, was the native of a small town in Southern Mexico. There’s nothing special to say about it.
What was your father’s main occupation then?
Well, actually when he was in Germany he wanted to study chemistry. But he never really finished. When he came back to Mexico, he had various enterprises related to chemistry. For example, he had a plant for distillation of wood products, like acetone and methyl alcohol and that sort of thing, in a very small scale. At some other times he ran a drug store, and also he was a teacher in a small college of languages. He happened to have a special facility for languages. He taught four or five languages. So that enabled him to survive.
Did he teach these languages to you? Was it a multilingual house?
No, at home, besides Spanish, we talked a bit of English only. We never talked German, which I really felt the lack of later in my life. He tells me that when I was a child, I used to listen and to understand German and to answer a few words, but I really never spoke the language. In my old age, I had to learn it the hard way.
What about Spanish?
Yes, Spanish was native to me. It was my first language.
But you did speak a lot of English.
I spoke quite a bit of English when I was a young man.
Was there a reason for that?
I think my father was very much disappointed about his own experience in Germany in the old country. And I think he realized that there was a very small chance that I ever would go to Germany. In fact his own close relatives lived here in the U.S.A And since english was not taught in public schools he probably thought I would learn it at home, I think it was a wise decision on his part, but he should have taught me German also.
I’ve heard the name Münch referred to in the literature by Hertzprung and by others in 1913 and 1914 from Potsdam. Is there any relation?
No, no relation that I know of. But you are correct. There was an old gentleman Wilhelm Münch who worked at Potsdam. There is a famous paper on calibration on the solar constant by Wilsing Schemer and Münch, But as far as I know, there is not any relation to me. Its a very common name in Germany. As far as I know, in my family there is no professional astronomer or any academically inclined mind on either my mothers or my fathers side.
Lets talk about your early schooling then and your family in that regard. You have a brother.
Yes, I have a brother and a sister. Thats correct.
This is Luis Münch?
Luis, yes. He was for a while in astronomy and we did some work together, small work. But my brother never got a formal education in astronomy, so he just worked at the observatory starting in the ranks as more of a night assistant. And he came to this country and did a small amount of work.
Was he younger than you? Are you the oldest?
Hess one year younger than I am.
And your sister?
My sister is four years younger than my brother.
I’d be interested now on the early period when you were growing up what your influences were.
Well, the fact that my brother did some astronomy with me later, came about at a much later stage. Already I had been in the U.S.A. for quite a long time. Now, going back to the early influences I had in astronomy in my childhood, perhaps I should tell you an incident, which was curious. I grew up in the early ‘30s, in Mexico. There were no churches. They were closed by the government.
Churches were closed?
Yes, the priests were expelled, and so on. But, you know, the Catholic Church has always been very firmly in control of the situation. Although there were no open churches where I lived the Jesuit Fathers had what you would call a Youth Club • There was a library and some ping-pong tables. And it was essentially an after school play activity. And the leader owned a telescope. So there was a telescope, and when we were good boys we got to look through the telescope. And that’s my first recollection of looking through a telescope.
What was your age and what city was this?
My home town, where I was born, was San Cr1 stobel, Las Casas. And I must have been about eight or nine years old. But the interesting story I’m going to tell you is the following: Many years later, I was at the Yerkes Observatory already, one day Miss van Biesbroeck, who was the librarian (the sister of Professor van Biesbroeck), came down and told me, “There is a 2entleman visitor, who talks only Spanish. Will you come and talk to him? And I came upstairs, and this was the old priest. By this time he was extremely old. He must have been in his eighties. And he was rather blind, so he hardly could recognize me. But he was the man. Of course, he was very happy to see me.
Did you show him your telescope? (laughs)
(laughs) Yes, I showed him my telescope. So that’s my early influence. Of course I do not think the telescope incident of my childhood had anything to do with the future developnent of my education really.
But he was a Jesuit.
And what was his name?
His name was Camilo Arguello. You know, as Don Camillo, the novel of Giorgio Puzzo.
What sort of things did he show you with the telescope? Do you recall?
I remember the moon, of course. I think we saw Jupiter.
Did he talk to you about them? Anything you recall?
Yes, In fact, he gave me a small book by Flammarion, to read, a small guide to the sky or something like that.
Flammarion wrote many many books like that.
Popularizing books, yes.
And so that was probably your first book and first contact.
My first contact with astronomy, yes.
Was your early schooling through this youth club? How was it accomplished?
No, elementary education was strictly through the formal public school system. We went to the primary school, which was seven years, and then three years of so—called high school — the official public schools.
And this was in San Cristobel.
All in San Cristobel, yes. And there is nothing particularly that I can recall.
Any teachers that stand out?
Absolutely none. Especially in the physical and mathematical sciences, there was absolutely nothing. I didnt know anything whatsoever after finishing high school.
When do you feel in your recollection you began to know that you were going to go to college and pursue a college career?
Well, in the town that we lived in, in the more or less middle class that my family belonged to, it was taken almost as a matter of course, as granted, that you had to go to college and became sort of a professional. It didn’t matter what profession.
This wasn’t everyone in the town. This was the middle class?
Yes, the middle class. You needed sane amount of money to go to a place where there was a university, generally Mexico City. The wealthy people sent their children to Spain or to France, but we were not in that class, so I was going to Mexico City. I discussed it with my father, but the only extent of our discussion was: “What would you like to be, a doctor, lawyer or engineer?” Those were the only three possibilities.
What did you say to him?
Well, initially I agreed to become an engineer. I went and studied engineering to the University of Mexico. Now, the University of Mexico has something called the preparatory school. Before you come to the University, you enter this. It is something like an affiliated college, at the level of a junior college.
It was called the preparatory school?
I took the preparatory school for engineering, and then I entered the school of engineering, which for me was to be civil engineering school.
And about when was this?
I entered civil engineering school, in 1938.
You were 17 years old.
Did everyone go through this preparatory school?
To enter any kind of higher education, you had to go to that preparatory school, yes.
There were a series of graded exams?
That’s correct. It was a nation—wide institution.
And did anything happen to you of significance in the preparatory school first?
Yes, in the preparatory school actually we had quite good teachers. And I had a teacher in physics in particular who I thought was quite exciting. I didnt know anything, as I said before, about physics or mathematics. But this man, while he was no great physicist, of course, knew something about it and really was able to arouse some sort of curiosity about physics.
But youd already been interested enough to sign up for civil engineering and mechanical work,
What do you think was the influence on you that had you go in that direction?
Well, I think it was completely negative. I didnt want to be a doctor. (laughs)
But did you see a possible need in your town for a civil engineer?
Not really. Actually perhaps there was something. During that time the middle 3Os - was a period where in my state, roads were being built, and there were quite a number of young engineers that used to be friendly with my father and used to come to the house, and I think that I liked these men. Also I didn’t like the doctors or lawyers of the town.
Was it possibly something about getting into the outdoors?
It might have been something. I must say: I forgot to mention this: in this town there had been a university at one time, But at my epoch the only school that remained was the School of Law, So the town was just full of lawyers. There were more lawyers than shoeshine boys.
Thats fascinating. But usually there’s a very directed influence that would bring you to something like astronomy. I know you said it was a negative thing that brought you to it, But could it possibly have had something to do with geometry, something in mathematics that stimulated you?
At that time I dont think I really had a notion, I mean I was not smart enough to realize the object of the whole thing. I really didnt have a concept of what either mathematics or the physical sciences were.
When the churches were closed, how did this affect your family? Was your family very religious?
It really didnt affect them at all. I remember my grand mother had a chapel in the back of her house, and the priest came every Sunday and all the family very happily joined her at breakfast and to hear mass. So it really didnt affect us at all.
And how about you? Were you affected?
I think very little, too.
I see. Well, then were back to the preparatory school and the physicist which you mentioned.
Yes, There was a good general physics course, and I really liked it, and I was happy to enter the engineering business. Then I remember my teacher of differential geometry was quite good, too. He was a man who had quite a greater influence later on.
Do you remember their names?
Oh, yes, The physics man was called Efrén Fierro, And the math teacher in college was Sotero Prieto, So again it was nothing more than curiosity to know more about physics and math.
Where do you think the curiosity came from, though?
I really cannot tell you. I wonder if it was also negative. I remember, for example, that I had a dreadful chemistry teacher and I just became to dislike chemistry.
Was it a laboratory course? How about physics? Did you have a laboratory course?
We had a very poor laboratory course. But we did have a laboratory.
What was the fascination then and the curiosity that developed? Was it through handling laboratory experiments? Or was it theoretical, abstract?
No, I think it was just the lecture, the manner in which it was given and the manner in which this man talked.
Was there a certain logic to this?
Yes, I think he was a very very good teacher,
What branches of physics were covered?
Well, very classical kinematics and dynamics. Then in the second year we got a little bit into electricity and magnetism, but no modern physics of any kind.
When did you first encounter modern physics?
Had I stuck to engineering, I never would have heard about modern physics, When I went to the School of Engineering the first two years were all right. It was mainly a continuation of college. A little more math, a little more dynamics, more advanced thermodynamics the second year, really ground base physics.
Was this all in Spanish?
All in Spanish.
And your texts were Spanish.
No, most of the texts were in English. They were American texts.
Which texts were you using?
Its hard to remember. But I can remember some of them Osgood Advanced Calculus, I think that was. Vector Analysis was Phillips. Standard books absolutely standard. So the first two years of engineering appealed to me because they were basic subjects. At this time I met another good teacher who gave me Vector Analysis. By this time I was dedicating myself more and more to the basics and not sufficiently to what was engineering.
Was the preparatory school a two year course?
Two years, yes. And once you are in the professional school the next two years are still only basic, just like college, because a career like civil engineering takes five years. And that was because you take two years more on basics, and just the last two years are concerned with engineering proper.
And you would have graduated with a bachelors degree in engineering if you had completed that course?
Well, actually a little more than that, I would imagine something equivalent to an engineer’s degree here in Caltech which is awarded one year after finishing college. The fifth year.
With your obvious interests in the basics, when did you become aware that you were more interested in the basics than the application?
It was in the third year when we started taking very specific engineering courses. As I remember, some were dreadful. There was one called thermal engines, like steam and diesels and all those things. That was dreadful.
So again there’s this negative element keeping you to a little more pure interests.
Yes, So I had to take refuge in something. When I was in third year I realized that I was not going to become an Engineer, But at the time there was no school of science in Mexico; there was not a Faculty of Science in the University only the School of Philosophy had a branch where pure mathematics was taught, and those courses were given in the school of engineering. So I kept on attending those courses, in the beginning just as an auditor. And probably by the end of the third year I already had decided not to continue engineering but changed into pure math.
During this period when you were making these decisions, did you talk about your likes and dislikes with your professors, with your family?
No, nothing of the sort, With fellow students, yes, There was not any kind of counseling or any kind of personal contact with the teachers. It was completely up to us, the students, And, of course, I wouldn’t dare to talk to my family. By this time, although I was supporting myself and didn’t depend economically on my father, I would have, had to said to my father, “I don’t want to become an engineer anymore.”
What did he think about engineering initially?
Well, he was all in favor of it, but of course he didnt have any idea of what it was,
But he certainly wouldn’t have wanted you to go into a purely academic subject.
No, I’m sure he wouldn’t approved of my going into mathematics.
When did you become independent of him economically?
Just about in my third year. In 1941.
And how did you do this?
Well, I had a job as a galley proof reader for the Journal of the Supreme Court of Justice of Mexico. I used to read galley proofs for a Weekly publication called the Judicial Semanary of the Federation.
How did you get that job? Did you apply directly? Was there an advertisement of an opening?
No, no, in Mexico those things are done because you have a friend or a relative. I went and talked to a relative of mine, a re mote uncle, who was on the Supreme Court of Justice, so I got the job.
Did you want to be financially independent then of your family? Did you know that this was going to be a problem in making this change?
Yes, There were problems before. And I also thought that my father couldn’t afford it anyway.
He did support you the first two years?
Yes, in fact he supported me almost the first four years.
And so you knew that to continue you had to have a job and to have a free decision on your own future, you had to be financially independent.
Yes. So by 1941 as I said, I was financially independent, and I attended some of the math courses. The math courses were very disorganized. There were two or three courses and the teachers were not very reliable. Sometimes they didn’t show up.
Were these math courses still within the engineering?
No, they were in the school of science, which was a branch of the school of philosophy. At the time there was a group of students, a bit older than I was, which was really active. We had study groups and we used to get together even on Sunday mornings.
Did any of these students turn out to be lifelong friends?
Oh, yes. I still see them, In fact, some of them became very distinguished men.
I would appreciate names.
Well, we used to meet on Sunday mornings and one of the books I remember was Goursat, Itss a classical book in mathematical analysis on Real Variable theory, Its a killer. Its like Volume 75 of the Astrophysical Journa— that big!
That’s quite thick.
This was really very productive. Let me mention some of the men who used to take part in this. I was really one of the juniors. For example, Carlos Graef, who got his Ph.D. in physics with Sandoval Vallarka at MIT, and later he became head of the physics department in the University of Mexico. Nabor Carrillo also got a Ph.D. a few years later with Casagrande at MIT on soil mechanics, Later Carrillo became president of the University of Mexico.
Thats quite a good group.
There was another young fellow called Javier Barros Sierra, who was closer to my age than the previous two men. He never came to America, but he also became President of the University, a very good man. So that was real the initiation to my formal study of mathematics the Sunday morning club.
Why do you think the club formed? Was it the disorganization of the University?
Yes, I think so. By this time it was 1941 and there were quite a number of visitors from the United States. And perhaps the man that had more influence than anybody else on the development of the whole group was Solomon Lefshetz, who was head of the math department at Princeton. I don’t exactly recall when I met Lefshetz. It must have been in the summer of 42. In 4l there was an observatory dedicated in Mexico, That’s something very important because it’s when I really met by the first time professional astronomers.
Was this Tonantzintla?
Tonantzintla, yes. It was dedicated I think at the end of 4l, and the Mathematics students were given some sort of invitation to attend the lectures of the great men.
Anyone at the University in the sciences would have been invited?
No, actually Carlos Graef, whom I mentioned before, was appointed assistant director of the Observatory, and through him I think we were invited. Anyway we went to the party, We didn’t know what it was all about, but we went.
Was there any astronomy discussed in the group?
Yes, there was, but that came a little bit later. Only from the purely formal point of view. We were interested in Poincare and things like that but nothing connected with astrophysics. Carlos Graef was in physics. He was a cosmic ray man with Vallarta, But he was more inclined to pure theory, More for curiosity than anything else, we went to the dedication of Tonantzintla, where we heard great men talk about matters we did not understand but I remember some lectures and lecturers very clearly, as Henry Norris Russell and George D. Birkhoff. George D. is the grand old mathematician who wrote And I remember very clearly because both of these men looked to me like brothers.
Did they speak at the dedication?
Oh, yes both of them spoke, It was a long program. Many other famous men were there, Shapley, of course, was there, together with Fred Whipple and Donald Menzel, the last one in his naval uniform. Cecilia Payne-Gapasckin was there, I don’t remember if it was 4l or 42.
We can check that certainly through the publications
Vyssotsky was there, 0. Struve was there, Nick Mayall, W.W. Morgan Bart Bok and a few others were there.
That was quite a contingent.
Quite a contingent. But actually I got very little out of the conference. Too much too quick: these people were talking about strange things.
What about the nationals? Guillermo Haro — was he there?
Haro was then a young man,as he is about my age. But something came out of that. For example, there was another man about my age who also belonged our Sunday morning group, called Felix Recillas, He is considered to be a real Mexican because he’s 100% Mexican, no European blood of any kind, both mother and father actually native.
Does that mean Indian?
Yes, pure Indian blood.
Is that considered an aristocratic element?
Not really, but he was very proud that he was a full-blooded Indian. And as a result of this meeting (meeting Shapley and Bok) he went to Harvard where he met and married a Turkish lady, Paris Pismis, with whom he came back to Mexico, Actually Recillas never finished his Astronomy education, Although he worked with Bok for a while, he did not like it and he went back to pure mathematics. Eventually, he ended up with Lefshetz in Princeton where he got his Ph.D. But the whole thing came out of this meeting. Now, my coming to the States is also to some extent a consequence of this meeting.
That was my next question.
This you will find in this letter of Struve to the director of  the Tacubaya Observatory. I’m missing one essential point. I left the galley proof reading business some time in 1942, because a friend of mine, who had a small job as an assistant computer, at the National Observatory, had left it and he told me, “I’m going to leave this job, and you should go and apply for it,” So I got a job at the observatory doing small computing, with hand crank machines.
And this friend was also a friend through the University?
Through the circle, also one of the members of the Sunday morning circle.
Had he gotten this computing position initially through his interest in astronomy or was it a job for him?
Not in astronomy really, It was just a small computing job, Something for a student to do as an assistant.
Did the National Observatory keep time at that point?
Exactly, yes. Besides time keeping, computing related to the preparation of a yearbook with Ephemeris and calculation of plate constants for the astrographic Catalogue was carried out at Tacubaya and thats what I was mostly concerned with.
You took that over.
Yes, in ‘42 after the dedication.
What had actually happened at the dedication itself that had stimulated you?
Really nothing. We had a good time and we listened to the lectures but we understood very very little about it.
You don’t recall anything.
I don’t recall anything in particular. The interesting thing is that a few months later—it must have been towards the end of ‘42. Struve wrote a letter to the director of the observatory Tacubaya where I was working. The director’s name was Joaquin Gallo. And Struve wrote a letter offering a position as I think he called it assistant observer at McDonald.
Why do you think he wrote to the National Observatory at Mexico for this? Was that the only letter he wrote, or was this a circular letter do you think?
No, he wrote specifically to the Tacubaya Observatory, although he may have written also to Tonantzintla. That letter was posted at the Bulletin Board, I don’t know where it is. It was written in the spirit that “now that Mexico has an observatory, I’m sure that young people will become interested in larger facilities, and we would like to offer . . .” By the time this letter was posted I was getting pretty bored, as this work required no learning of new subjects. So I went to the director and told him that I would like to apply. And he said, ‘You would like to apply? But you are not interested in astronomy. You just like the little numbers.’ ‘No,’ I said, ‘I would like to apply.’ And so he wrote back to Struve and Struve wrote a letter to me and a letter to the American Consulate in order to arrange the required papers, which took about three months. That was in the beginning of ‘43.
That would have been your fifth year.
You were still in school when you were the computer?
I was still in school, yes. And I was supposed to be writing a master’s dissertation. —
Did you go directly through the master’s without the bachelor’s? How did that work? When did you get your bachelor’s?
No bachelor’s degree is formally awarded really. There is preparatory school and then professional school. And I went through all the courses in mathematics that were required for the master’s degree, and I was supposed to be writing a dissertation, But I didn’t find anything to do, I was just lost, wondering around what to do. So I didn’t take at the time a master’s degree and I came to the United States without any degree, Actually my official arrival date was April 1, 1943.
But they wanted an observor at McDonald?
Yes, but they sent me to Yerkes first, where I was for about one month, perhaps a little bit more. From there I went to McDonald, where I stayed till September 1943. Essentially my job was something like a night assistant.
Was it a training period at Yerkes for that month?
No, at Yerkes I was considered an auditing student. I sat through some courses, some lectures. I talked to people. I then met Chandrasekhar for the first time.
What were your impressions at that time? Was this the first time you were out of Mexico?
How was your English?
It was not really very bad, I could sit through the lectures and understand without any trouble, and I could express myself, I could say anything really.
Did you have the feeling that you would have preferred staying at Yerkes rather than going to McDonald? What went on in that month?
Well, the whole thing happened too fast, I didn’t have time to gather my thoughts in a coherent way. I knew I was supposed to go to McDonald and I sort of wanted to see the telescope.
The 82—inch, yes. And so I went to McDonald and I worked with Struve mainly. It was during the war so there were very few observers. Struve used to do months of observing by himself, W.A. Hiltner and Gerard Kuiper came once in a while, and there was a local Astronomer superintendent, Jose Yoss. So I spent many many nights with Struve. I used to guide for him, develop plates for him, and do what a night assistant does, as preparing his midnight lunch. I really enjoyed it very much. In these long nights on the telescope he used to talk a lot about what he was doing, what he was doing with SX Casseopeia, for example, and anything that at this time he was working on.
In 1943 you did publish a paper on a spectroscopic binary. 
Yes. He wanted me to learn something practical about astronomy. Already when I was at Yerkes, Struve taught me how to measure a spectrogram for radial velocities. He had a number of pet stars he used to follow for years and years. And I measured a few plates for him, and he said, “Why don’t you measure a star for yourself. So he gave me a whole stack of plates of 0^2 Orionis which I measured. Then I determined the radial velocities, the orbit for the star. Also Struve and Kuiper gave me a list of faint proper motion stars to observe, as a backup, when there were a few hours available at the telescope, when some other observor did not show up. So I had my list of stars to fill in the time when available.
You were getting spectra for faint proper motion stars?
Yes, and that was another paper that I wrote, the next one. 
So then he very rapidly regarded you as more than a night assistant. Why was that? Did he treat everyone that way?
Probably not, but by this time Struve knew, through our talks, that I had an idea of physics. I completely forgot to tell you about my modern physics, how it came about. I’ll go back. So I knew that I understood more or less what he was working on. I understood mechanics quite well—I would say advanced classical mechanics. Especially Kuiper was very much impressed once we had a discussion about celestial mechanics, when he said “Obviously you are not going to stay here. You should go back to Yerkes and study.”
Kuiper said this and Struve?
Struve also. But I had to approach Struve to tell him that I was going to be in trouble. I received money for being a night assistant, and there was a slight catch. That was a job, and as a job holder I was subject to be draftable and I was registered with the Selective Service.
In the United States.
Yes. I never was called, but I was registered. If called, I was expected to serve, although I could refuse. I could have stayed in the USA even if I had refused. The only penalty is that I could not have ever an American citizen.
This was for foreign nationals.
During wartime foreign nationals can be called to serve, but they cannot be forced as U.S. citizens. Well, anyway, there was another complication. It came about because of the following: When I talked to the American Consul in Mexico he warned me, ‘You know, this is a job. You’re being offered employment as an assistant observer. If you go as an employee to the United States, we have to give you an immigrant visa.’
‘We have to give you an immigrant visa. If you work with an immigrant visa, you’ll be drafted right away. So we’ll give you a visitor’s visa. And then at least you have the choice.’ Okay, so I came with a visitor’s visa. But the immigration department, caught the fine distinction between visitor’s and immigrant and I was invited out to leave the country voluntarily in lieu of deportation, because I had accepted employment with a visitor’s visa just to avoid the draft. Actually, I did it on the advice of the American Consulate officials, but the fact is that I had to leave the country in ‘44.
You had to leave the country.
Yes, I had to leave the country in April,‘44, when my year was over, and it was obvious that I could not cane back unless I had a fellowship. I could not cane as a night assistant again. I needed a fellowship. So I went back to Mexico to get a fellowship.
You got your master’s in that period.
I got my master’s in that period, essentially with something I had been doing with Chandrasekhar at Yerkes.
What was that?
Radiative Transfer. (laughs)
Of course. Well, before we go beyond ‘44, why don’t we go back and talk about that modern physics.
Oh, the modern physics, yes. Well, in the third year in the school of science I took my first modern physics. There were two men who taught physics. One was Aifredo Banfls, who in fact until a very few years ago was professor of physics at UCLA. He gave lectures on Slater and Franck, Theoretical Physics following Slater and Franck well known Textbook. The teacher of modern physics, a little bit on atomic and nuclear structure, was a Spanish refugee, of name Blas Cabreroa. He was a good man except he was extremely old, He was way over 70 by this time. But he actually was a good lecturer. He knew what he was talking about, Especially classical atomic physics — the Sommerfeld stuff, he knew very.Our textbook was in fact Sommerfeld. Another man, who also was a refugee in Mexico, and who had been director of the observatory in Madrid, Carrasco. Gave me my first course in geometrical optics in the school of science.
Was this course a tutorial?
No, it was a formal course.
Were you the only student?
No, there were four or five.
Did you ask for this course or was it something that he volunteered to give?
There were a number of courses in the catalogue that were available on request, if anyone was interested. So essentially we asked for it.
But you never did take anything that we would call formal astronomy in Mexico.
No. Well, not formal astronomy. There was something called Astronomy of Position, which was more connected with geodetical measurements, that I took. And, in fact, when I was employed at the Tacubaya observatory I did some field work of similar nature for the Carnegie Institution of Washington. It was a magnetic survey of Mexico, I observed quite a number of stations doing magnetic field measurements.
During this period when you did learn the modern physics in your third year, were you interested in the physics itself? Was astronomy in the background? This is before you took the computer job, I take it?
At about the same time.
Did you see a connection between the two?
No, I did not see any connection between my job in astronomy and what I was studying at school. I still did not know what I was going to do.
Okay. So you had no idea that there was going to be a connection.
I had no conception that it was going to happen. In fact, in ‘44 when I went back to Mexico, I became better acquainted with Solomon Lefshetz. By this time I had a little bit more knowledge or maturity to really understand Lefshetz. And I was very much impressed by him, to the point that there were doubts in my mind as to whether I should go back to Yerkes or to Princeton with Lefshetz instead.
What were some of the deciding factors?
Well, I talked in length to him about the matter, and he said, ‘You know, at the present time we don’t have any formal courses at Princeton. Perhaps you could come and you could meet Feller and perhaps you could see Solomon Bochner once in a while. But all of them are doing war work. So I could talk to you in the nature of tutorial courses, but you could not get formal lectures.’ After sometime I told him I was interested in definitely going back to Yerkes to study with Chandrasekhar. Because of my previous mathematical training, obviously I was able to understand more the kind of work Chandrasekhar did than that of others.
I would like to talk a little more about your first contacts with Chandrasekhar when you feel it’s appropriate.
Yes, we’ll go back. But at this time Chandrasekhar also was half time doing war work, too. As you know, he was at Aberdeen proving Grounds doing war related work in association with John von Neuman. In fact he also used to spend the weekends with von Neuman in Princeton. For this reason Lefshetz told me, “Well, you could see Chandra at Princeton also. Half of his time is near Princeton, and the other half he spends at Yerkes.” In any case, in order to return to the U.S.A. I had to get support and that was the main problem. Lefshetz finally said, “No matter what happens, you have to go back to the United States.” So I got recommended by Lefshetz, Struve and Chandrasekhar, to obtain a Latin—American Fellowship of the Guggenheim Foundation, which is a very nice fellowship. When I was awarded the Fellowship I decided to return to Yerkes to study with Chandrasekhar. I had met Chandrasekhar of course, when I first came to Yerkes in ‘43, when I sat through some of his lectures, and because they were to some extent formal I was able to understand more of them than other subjects taught also at that time.
Were these lectures specifically on radiative transfer or was he working at all on white dwarf problems on the limitations of mass of the core?
No, that time was over.
That was all over.
Yes, Chandrasekhar’s stellar structure period was in 40-41. In 1943 I think he was working and lecturing on Stellar Dynamics. The courses were strictly formal, but with the help of his book I started to follow them. He often used to ask me questions as “Do you understand it?” Through our talks I think he became convinced that I was getting something out of his Lectures. And that is why he encouraged me to return to Yerkes. I think I have a letter from him in this respect.
That would be one of the good letters to preserve.
I think I have that letter.
But the influences of Lefshetz on my decision to become an astronomer was quite important. In fact the whole group in Mexico really benefited from him enormously. He must have brought to Princeton four or five Mexicans to obtain their Ph.D. in Mathematics.
What brought him to the University of Mexico? Was he invited there?
You know, at that time the State Department had an exchange program of American professors, short lectureships, three months, And I met several, I remember two perhaps. There were many more, but I do not remember their names. They must not have made a great impression, I remember the statistician Paul Rider, But Lefshetz happened to like Mexico, and he used to spend all his summers in Mexico, In fact, at one time he talked about retiring in Mexico, Of course, he never would be a man that would retire, and he never retired, Finally, he died at work, But he liked Mexico, and after going the first time invited by the State Department, he continued his visits until the 5Os.
Marvelous, I think summers down there are much nicer than the humidity at Princeton.
Well, we’re at the period now when you worked both with Struve and with Chandrasekhar, and in 1944 and the following year or two you were attending various courses, and you were doing research. You had a 1944 paper, “Radial/Velocities of Proper Motion Stars” - This is what you mentioned— but then you were also very interested in Chandra’s work. I’d like you to sort of give me a general impression of what Yerkes was like upon your arrival, specifically as a student now and how your interests were directed.
When I arrived at Yerkes, of course, it had gone down from its peak, because of the war. There were relatively few people. There were relatively few staff Members and very few students, Perhaps there were six or seven: four girls and three men.
Who were they? If a name comes to mind, that will be fine.
The girls, yes, I remember them: Margaret Krogdahl, Marjorie Harrison and Merle Tuberg. All of them finished and Margaret Krogdahl is married to Wasley Krogdahl. Marjorie Harrison is teaching at a small college near Austin still today. And Merle Tuberg first married Richard N. Thomas, and later she married Tommy Gold.
What was the atmosphere like? Of course, these were the war years.
It really was very very quiet. There was relatively nothing else to do but study. The courses kept on going regularly.
Who taught these courses?
Well, Chandra, Morgan, Struve sometimes. I don’t think Struve particularly liked to give courses, but he gave a course in stellar spectroscopy.
That must have been a marvelous course. And Morgan on photometric systems?
Yes. He gave photometry sometimes. Yes, that’s correct. J. Greenstein and L. Henyey were there. They were doing full time war work in the “Observatory Optical Bureau.” But still Greenstein gave us some lectures on stellar statistics and the sort of work Bart Bok had done a few years earlier. Coming from a completely disorganized medium like the University of Mexico, the ascetic atmosphere of Yerkes was quite a change.
How about the social situation at Yerkes?
There was no real social life. We lived in the observatory, We lived in the attic.
In the battleship.
In the battleship I lived together with another student, John Swensson, who also became an astronomer but left this country many years ago, We did nothing but go to classes and study, We didnt have automobiles and consequently we couldn’t go anyplace.
There was no interaction with people in town?
Very very little.
I’m interested in the primary figures, of course the people that you worked with. Babcock had left probably the previous year. These are from catalogues of courses, so it’s difficult to test the accuracy. Greenstein, of course; Thornton Page was an instructor, There is quite a long list of names.
It is difficult for me to remember all the people I met at the moment. Certainly Prof. van Biesbroeck was there. Although van Biesbroeck had very little to do with the students, he enjoyed to visit the students often to his house and talked to them, I used to talk to him very often. He was a great man, but he talked relatively little about science.
What did he talk about?
He used to talk about his comets mainly: The Definitive Orbit of comet Delavan for example. He had the students over to his house probably more often than any other faculty member, for Thanksgiving and other holidays.
What were your impressions of Struve? You knew him briefly before that when you were the assistant.
Yes, when I was his assistant at McDonald.
And so you had a personal relationship with him.
Yes. He was a really remarkable man. I wish I could remember the stories he used to tell. He used to talk and talk and talk all the stories of his youth in Russia and how he escaped. His adventures in Turkey and how he came to the United States.
Do you recall any of these stories?
Well, I don’t know if I would recall them accurately enough.
Who would be a source of these?
I really don’t know and I am afraid that I really could not recollect the stories that night after night Struve told me.
What about your professional relationship? How did he teach you various techniques and what were his mannerisms? How would he show you how to measure a spectrogram or something like that?
He was very dry and short of words. He sort of would give a general description of procedures and then expected you to follow them, One of the letters that you will see relates to the following incident: He was interested in the star SX Cas, a 30—day period, spectroscopic and eclipsing specially at the primary minimum. For some reason he had to go back to Yerkes on the date when the primary minimum would take place. The previous minimum had been cloudy and he had to wait 30 days for the next one. So he left after telling me, “Be absolutely sure that you get it!” The following night it was already in minimum. When the first phases of eclipse came I had clouds, so that night I went to the telescope in the settings, and took care we used a visual finder since the circles were not very accurate. So I set it visually and told to myself “Oh, that’s the star.” I took a spectrum, a long three—hour exposure, and when developed, sure enough, showed a G—Type spectrum as it was suspected to be. Fine. The next day again it was clear, and immediately, I set on the same star, making sure that it was the same star, I think it was still supposed to be in partial phases. So there was no surprise when I developed the plate and looked as the same, perhaps a bit brighter, G—star. By the third day it was supposed to be out of eclipse, but when set on the same star and find still a G—spectrum, I realize that it was the wrong star. Exactly one degree in declination off! How could I do that? But I set it without doubt in one degree off every one of those three nights. So I had to tell Struve my error by letter, He wrote back furious, as that famous hand-written letter shows. 
This letter I’ll be able to see.
That letter, yes.
A rather sad consequence had this incident. There is no question that I was responsible for taking the wrong star. But there was another fellow there with me at McDonald who also was a student at Yerkes and whose name is Carl Bauer. He still is in science. I think he’s in Pennsylvania, perhaps Penn State. Well, Struve wrote me a letter and really he almost fired me right on the spot. (laughs)
I’m glad we can laugh about it.
But Carl Bauer also got it, indirectly, because we both were supposed to be observing. Struve wrote to Bauer: “you should have watched Münch.” So Bauer got a little bit of the noise, too. Of course, what I could I have said after my mistake but “I’m sorry. I’m stupid. I’ll try not to be so stupid next time.” But Bauer got in an argument with Struve because of the wrong star.
What was Bauer’s position?
He was also a student-assistant. Struve really should not have castigated him because it was not his responsibility — it was Münch’s responsibility. I made a bad mistake and accepted it, but Bauer got in an argument and eventually he had to leave Yerkes without obtaining his Ph.D. Actually Bauer had extremely good ideas, which unfortunately other people exploited. It’s one of those strange things.
Well, how was Struve then in this regard? Was he very dictatorial?
Extremely so, but he was fair. I think he was very fair. No question he ran the observatories with an iron hand. I mean everything that happened at Yerkes was absolutely under his thumb. He was a real dictator.
Was there a phone between Yerkes and McDonald at that time? Was this the mode of communication? Or was it by telegram or letter?
It mostly was by letter.
He didn’t designate any associate directors or any other people with responsibility?
There was an associate director, Mr. Dersham — you have it on your list — Dersham was a retired physics professor from the University of Chicago, who was in charge of the physical plant, but had nothing to do with the observing.
So no one else really had any aininistrative power. Struve had it all.
Nobody. Even at Yerkes. At times the staff — grown up men — obviously resented this absolute power that Struve had and being treated like small children.
Everybody, yes, everybody. (laughs) Perhaps I’m getting a little bit ahead, but I witnessed the power of Struve in faculty meetings when I was a very junior member of the staff and of course I couldn’t say anything.
This was already 1947.
1947. At meetings of the staff presided over by Struve everything was very democratic, everything was discussed, and then he said, “Well, gentlemen, I strongly suggest that we take the following course of action.” (laughs)
And that was it.
That was it.
Well, how did Chandrasekhar react to this? Was he involved?
I never found out. I know Morgan hated it and resented it. There was incredible resentment that I didn’t find out until way after Struve was dead. I saw Kuiper standing in front of a seated Struve rubbing his hands like this, you know — like a small child and saying: “Yes, Mr. Struve.” It was like that. (laughs) Well, I could say nothing because I was very junior, but it was really somehow frightening to see these big men not being able to stand up to him.
Could he dictate also what was to be done with the telescopes? In other words, what modes of research, what problems would be attacked?
I don’t think so, but one had to have his general agreement, okay? One had to explain to him. There was some sort of observing request and he had to approve it essentially. He asked good questions: “What are you going to do with this material?” and so on. But I don’t think that the senior members of the staff were really pushed in a particular direction. Certainly the students’ observing duties at Yerkes or down at McDonald were completely dictated by Struve. But he did not do the observing. The students and other people did. He prepared the observing programs and assigned priorities.
What were Struve’s relationships with campus to the best of your knowledge? Were there pressures at that time to move the facility to campus or were they riding pretty easily?
I don’t think at that time there were pressures to move it to campus. There always was some pressure to have some member of the staff lecture on campus in the undergraduate courses.
Wasn’t Moulton still around or was he dead by then?
Yes, but he was not teaching anymore. He was still around. I remember Forest Ray coming once to Yerkes. Saturday morning we used to have visitors. We students used to take the visitors. And once the old man came in. He said, “Good morning, I am Forest Ray Moulton.” I said, “What can I do for you?” He said, “Nothing, I’ve just come to pay my respects to the 40—inch,” And he walked in up the stairs to the dome and then walked out. Thornton Page stayed on campus for quite a number of years. And Chandra used to go. I went sometimes.
Well, where was Herzberg?
He mostly was at Yerkes because he had a pretty large spectroscopy laboratory.
Now, most of this is after ’47.
Lets talk about your degree and your thesis work.
Well, my formal education was really not very complete because it went very very fast. As said before, I came back in ‘44 and did course work in ‘45 but by the middle of ‘45 I was already doing some research work under Chandrasekhar. So at the end of ‘45 they told me, “You have to get a degree. You’d better write something in the form of a long paper so it can be a thesis.” So in '46 I did my thesis and that was it.
Was that on the continuous spectrum of the sun?
That was part of it. But actually the continuous spectrum of the sun was more like a classroom exercise. Chandrasekhar was lecturing on stellar atmospheres, and at the time he was working on H-. I went a bit beyond what would be expected for the class problem. You know, I went to the old measurement of intensity, limb darkening and flux in the solar spectrum former analysis by Milne and Lundblad, and tried to fit the data with Chandrasekhar’s new values of the H-absorption co-efficient.
Right. This is what I noticed actually. In some of these papers around this time, you were acting as interface between Chandrasekhar’s theory and observation.
Were you consciously doing this? Did Chandra consciously to your knowledge want someone who could appreciate his theory and also interface the observations?
To some extent perhaps. You must realize of course, that I didn’t have a real understanding about the observation procedures involved in the photometry of the sun. That observation may sound trivial, but in fact it is an extremely difficult observation. So the only thing I really did was to trust blindly the data that I could find in the literature and fit them into the theory that Chandrasekhar had made. When I showed to Chandra the results he said, “That’s wonderful. Why don’t we go in addition the following:” So we kept on going. My first paper really was entirely a classroom exercise elaborated two or three times over.
Chandrasekhar was then working also on radiative transfer, and so there were many problems that could be tackled with his methods. And often he asked me “why don’t you work in this or that?” So I worked on a couple of problems—on the line blanketing problem and the other one on electron scattering.
It’s the effect of absorption lines on the temperature distribution of the sun.
Yes that is the blanketing problem.
The interest that I had in that line blanketing problem was that you were able to show a need for better observations, greater resolution. Were you becoming more and more interested in observation at the time?
Yes, yes. I had noticed it myself. And this is, of course, no criticism of Chandrasekhar. But I thought that sometimes when he quoted or he called on observations to strengthen a theoretical point or to verify theory, sometimes it was to some extent superficially. Of course, he always went to people that knew about it,—You know, to other members of the staff, But I sometimes thought that he was not quite certain of the grounds was stepping in. So probably unconsciously I was beginning to lean a little bit towards observations. Simultaneously with the work I was doing with Chandrasekhar I did some work close to W.W. Morgan I was observing with him small problems and also with Struve. W.W. Morgan taught me stellar classification, In fact, I wrote a small paper on the spectrum of cluster type Cephoids with a country man of mine, Luis Rivera Terrazas, who was under Morgan’s tutelage.
I don’t have that paper. I didn’t get that one.
Terrazas was in this country one year and we did that small piece of work together, this paper on cluster type Cephoids, We did some photometry, too.
At this time then would you say that Morgan, Struve, and Chandra were basically giving you problems and you were doing them and looking around at the general field?
And not necessarily forming any career choices at that time. Or were you?
Well, I think that it was already clear that I had to depend on theory to survive.
What do you mean?
To survive in school I had really to make use of my abstract inclination, I really didn’t have the knowledge or the background to really tackle a true observational astrophysical problem.
This was after you had done a number of those?
Why do you think that is the case?
Because I knew already how incomplete my education was. I felt rather helpless to design a spectrograph or to design a detector or to build a piece of electronic equipment. I was lost.
At that time, if I’m correct, Greenstein and Struve were designing nebular spectrographs.
Yes. That was Struve. Struve and C. Elvey were designing spectrographs. I mean the concept of the spectrograph. The actual optical design rested on old man Ross, Frank Ross. Of course, I met old man Ross here at Mount Wilson. But as my knowledge of astronomy advanced and I gathered what was going on in astronomy, I began to realize how defective my education was.
Was this before your Ph.D.?
Yes, before my Ph.D. In fact the realization of my ignorance really bothered me to the extent that at times I thought that I should go back to Lefshetz and become a true mathematician. I really thought about it, because I became aware of my lack of knowledge on certain matters.
These matters dealt with optical design or the ability to seek out observational problems?
No, physics, physics was the trouble. No, physics. I knew a little bit of atomic physics- but only on paper. It didn’t have anything to do with the real world. It was reading a book. It didn’t have anything to do with atomic physics the way it is.
Could it be, looking back on it now, the possibility that the physics that was available then was just barely beginning to be able to describe the sun and stars?
Well, one of my Bibles at the time, of course, was Unsoldes book. And if you look at the book, it has so nuch to do in contact with reality. It’s not an abstract thing. It has something to do with the real world, with observations and with measurements. And part of my frustration came because we really didn’t know how these measures are made, who made them, why were they made that way. Because we didn’t make the measurements at Yerkes or at McDonald. There was something missing. I wouldn’t say that my education in Yerkes was defective; rather that my previous education was very poor. There was some lack of contact with the real physical world. It was just a piece of paper to me.
Even at Yerkes.
Even at Yerkes, yes.
Did you feel that maybe there was another observatory that could fulfill that?
It wasn’t the observatory. It was that I didn’t have the grasp, okay, of what we were studying through the telescope. And that’s why I went to Chandrasekhar, because I thought that by doing a little abstract research or doing the algebra of whatever we were doing, I was more sure of myself. Realizing my lack of practical knowledge, I enjoyed working with Morgan. To Morgan observing was an art. It was not only an observation. It had to be perfect. So it was fun to work with him. And Struve also, he really was more practical and direct than Morgan.
Who else observed? Did Greenstein observe at that time?
No, Greenstein did not observe.
He was doing war work also at this period.
Hiltner observed a bit.
Hiltner was observing. It was just before his polarization?
That’s right. The polarization came when I came back to the faculty.
Well, let’s talk about — unless there’s something that we’re missing during the period you were getting your Ph.D. — how and why you returned to Mexico.
Well, when I got my doctor’s degree, I think it was always taken for granted that I was going back to Mexico. In Mexico they had kept a position for me. I was told: “Any time you want to come, you can do astronomy in Mexico.”
That’s very nice.
At the time the director of the Observatory of Tacubaya was old and there was nobody to succeed him, I imagined he thought: “Well, we can use this young fellow at the observatory. We’ll give him a “small” chair.” The observatory, of course, was absolutely decaying. After 50 years nothing had been really accomplished there.
They had mainly astrographic instruments?
Carte du Ciel?
Carte du Ciel, yes. And they had a small Spectroheliograph, a small camera, but nothing else. And so I went back. Tonantzintla was working. And I had also some arrangement that enabled me to observe at Tonantzintla. I used to go often to Tonantzintla, I had an appointment in both places. Thats the only way you could survive at that time. Actually when I arrived, the director of the Tacubaya Observatory had been retired, and there was another man formally in charge of the directorship, but I was there in fact running the place without any appointment. That was my situation.
This is '45, '46.
46. It was sort of interesting because at that time we were planning the new university, and many departments of the University had a representative in the council that met with the architects to determine the design. And really most of the year I spent doing that, sitting with the architects and pipe dreaming the great buildings and so on.
Where was the money coming from for that?
That was coming from the Presidency.
Who was the President?
Miguel Aleman, That was the summer of 47. I had already decided to come back, however.
You had already decided to come back to the United States?
Yes I went back in June of 1946.
That was to Mexico.
To Mexico. And that same summer I visited Lefshetz, who as usual was in Mexico. That year I tried very hard to work with the people at Tonantzintla, but the Schmidt camera was not working yet. They had all sorts of trouble with that Schmidt camera, and it was the eternal question of testing, testing, testing. I was also lecturing at the University.
Did you have advanced students at that time?
No. We had to give lectures to justify our earnings. I used to give elementary differential equations. So I couldn’t stay all the time in Tonantzintla. I used to spend my weekends there.
Did you have a family yet?
No, I was a bachelor. I was planning to get married after returning to the United States.
In the United States?
In the United States with a girl from Williams Bay, Wisconsin. Yes, I planned to get married on my return. That’s correct. I think it was in July of ‘47, exactly 30 years ago, when I got married and thereafter I went back to Mexico for a short time, but really at this time I had completed arrangements with Struve and Chandrasekhar to come back to Chicago.
How did they feel originally about your going back to Mexico after your degree? Did they think it was a mistake?
No, they said fine. ‘You might come to visit us sometimes,’ I remember Struve told me, but it was ‘we wish you very good luck and goodbye.’
Well, what changed things?
And then, you see, I wrote to Struve. No, I used to write to Chandrasekhar, because I kept on working on these little things I was doing with him. And I told him, “I think nothing is going to happen here, Chandra. This is a dreadful place. I think the chances of doing science here are nil.”
Too bad. But it’s not true anymore, I take it.
It’s not true anymore.
But at that time.
At that time it was. And perhaps I was too young and too impatient and so on. But whatever it was, Chandra heard my call for help and he wrote a letter: “I will talk to Dr. Struve,” and within six months he said, “You can come as an instructor,” and I went to Chicago. I think that’s another of the letters I have.
Now just about this time, when you returned, didn’t Struve leave?
No, that was considerably later. We overlapped about two years I think. Again, I have the letter to the staff in which he announces that he has resigned, and I have a copy of the letter of Hutchins to him where he expresses his sorrow for the termination of a long friendship and association and so on, but I never saw the letter, which I would have liked to see,from Struve to Hutchins. Apparently Struve was trying to get something with the threat of resigning and Hutchins accepted the resignation. Struve had done it before, I understand. He used to get his way by threatening to resign, but this time Hutchins accepted it. (laughs)
This is why he left.
He took his word. It’s a dangerous game. I’m not sure of that, but in that letter you can read something in between. I was in the faculty meeting where he announced that he had resigned, and he said, ‘Mr. Hutchins is a most unreasonable man. I don’t think I can continue here.’
What was the reaction of the staff?
. . . Let me go back a few steps.
There was a reorganization, and it to a great extent was a rebellion of the faculty, of the senior members of the faculty, against the dictatorship of Struve.
When did this happen?
It was in 1948. There were discussions between the staff and Hutchins. Struve and Hutchins and the staff and Struve. And it was decided to split the authority. It was a terrible mistake. Struve was going to become chairman of the department, and G. Kuiper would be director of the observatory, and there was a third one who was going to be assistant director for McDonald or something. I think there was a third administrative post.
Did Kuiper actively seek this?
Yes, I think so.
Was Morgan involved at all?
He was involved in part. He was involved because he was a senior member. I was not. The junior members of the staff were Bidelman and myself. So Struve was the chairman and Kuiper was the director, but the budgetary matters Struve held in his hands, and so Kuiper couldn’t do anything. (laughs) Struve held the purse strings.
Hutchins was the one that had the power to make this split. Do you think he was so short-sighted that he didn’t understand that the person who controlled the money really still controlled everything?
I don’t know. I don’t see why Kuiper accepted it to start with.
He accepted the title without control, without the power.
And then there was a stage in which Kuiper went to talk to Hutchins without Struve knowing it and that blew Struve up. That really blew him up.
What was Kuiper’s reason for acting . . .?
Well, because exactly this question of the budget.
But was it the way Struve was, his dictatorial ways, that kept other people away from him?
Yes. Kuiper was afraid of Struve, really afraid. That was an occasion, that meeting when he said he was leaving.
Wringing his hands, literally.
And standing up in front of him and sort of bowing. And Struve had a pencil in his mouth and chewed it (laughing).
These would be at staff meetings?
How do you think this affected the science at that time in all the projects that were ongoing? Yerkes certainly has changed in its position.
Yes, indeed. That’s a very very important question, a very important question. I don’t know. I think that the way the after effects— the way that things happened to turn out: I somehow think that Struve was right. He realized he had made a mistake appointing Kuiper.
Struve actually ended up appointing Kuiper.
Hutchins told him to.
Hutchins told him to appoint Kuiper, and he realized he had made the wrong choice, because while Kuiper organized and directed things, he was a very indecisive man. He never made up his mind. That really was maddening.
I can see that’s a very difficult situation.
I never recall one minute when Struve had the slightest doubt. The man was absolutely definite. No question about it. But Kuiper was just maddening. He changed his mind going from NcDonald to Yerkes he used to send telegrams on the way: ‘I shall arrive at 10:30.” Mother telegram: “I shall arrive at 1:30.”
And people were dependent upon him, too.
So you can imagine two men with such diametrically opposite personalities. They clashed. (laughs) There wasn’t any other way.
Did kuiper consult other members of the staff in order to make his decisions?
Certainly not me because I was out of it. Being completely junior, I was completely out of it.
Well, who else was deeply affected? You mentioned that 1organ was very adversely affected by Struve.
He never said anything. At least Morgan told me very privately many many years later: ‘The day Struve left, I felt I could breathe again.’
And he never said anything.
He never said one word. Twenty years later he told me this.
If my memory is correct— I’m not too sure about the timing, but I have the impression that when Struve did leave, Morgan had to take over for a short amount of time. Is that correct?
At one time he did. That is correct.
You were on the staff, of course.
Morgan took over something very important. It was the editorship of the Astrophysical Journal.
That went with the directorship at that time.
No, Struve had separated that one. Yes, he separated that one. But you are right: he was chairman for a while or director of the observatory. But I think that was after Kuiper left,
After Kuiper left, Were you still there?
No. I was not there. I had left, But again you are going to find that from somebody else I am sure. I never knew the whole story of why Kuiper left. I couldnt tell you what is my source I donut exactly remember besides . , Thats not the point. The story I have heard and taken with a grain of salt is the following: after Struve left and Kuiper became director, the University of Texas, owner of the McDonald Observatory, had begun to build an astronomy department and demanded a bit more time on the telescope and wanted to have a share in the running of their own place. And so there were some negotiations with Yerkes. The story I have heard is that Kuiper, instead of negotiating or reaching an agreement between Chicago and Texas which would protect Yerkes interests, he turned around and went to Texas and said, “Ill run the place for you.” The president of Texas called Hutchins on the phone and said, “I have had this man here.” (laughs) And Hutchins called the staff, called Morgan and Chandra, and said “Gentleman, this is happening, what do we do about it?” So that was the end of Kuiper.
You would want us to verify that story.
Yes, you should verify that story, because it obviously was something of importance. Well, let me tell you: I was told this by a man who had quite an important role in this business, but you better check it with some of the people. Kuiper is gone, so its a matter of history. But I think that something like that went on. I believe that. I heard it in fact from two different sources.
Okay. The importance, of course, is just this element of the effect on the continuity at the observatory, its international standing in science. And literally the only person who comes to mind of major importance who survived the entire series was Morgan.
Morgan and Chandra.
Chandra, of course. And somehow today its hard to associate Chandra with Yerkes as much as one would Morgan for the reasons that it seems as though Chandra is much more associated with Fermi lab and campus. But you’re right exactly.
Chandra stayed a long long time at Yerkes.
That’s right, yes. Well, I was there when he cleaned out his office, He’d already left, but this was in ‘66. But I’m very concerned with documenting the history of this very turbulent time at Yerkes and the effect on science, And maybe we could talk about your papers and how your interests developed through your years at Yerkes. Okay, We were just mentioning the existence of that letter, Again, for the record, to be sure that it’s on it, there is this correspondence between Struve and Hutchins, which should be consulted to know the full story of why Struve left, That was 48 now, and you were already on the faculty for a year, You must have had a number of students during this time and were developing your interests pretty directly, Could you review them as you recall them?
Again I was considering myself more as a student than as a staff member. At that time I can remember Nancy Roman, now of NASA fame and Ann Underhill, They were the two girls around.
I didn’t know they were both there.
Yes, There was an Edith Johnson who came from Vyssotsky. And a whole new group of G,I,’s had come right after the war, They were older men, I got along very well with them, Like Frank Edinonds and Douglas Duke, Edmonds is at the University of Texas now. Henry Horak also. Oh, there was quite a number of them, I don’t remember all of them.
Horak was a student of Chandrasekhar.
Yes, a radiative transfer man. The time when I was an instructor, of course, was extremely productive. Then I worked very very hard with Chandra, We did this series of papers on stellar statistics and the brightness fluctuations of the Milky Way, which I enjoyed very much, because by the first time I felt I was doing something myself, not only developing Chandra’s ideas.
That’s marvelous, That’s when you started feeling you had your own identity.
Yes, he was at that time very busy also with the radiative. transfer textbook and I helped him with the reading and proofing. It was a dreadful job proofreading the whole thing, For example, I made all the drawings for that book, all the formulas and so on. It was a very enjoyable time. In fact, the last piece of work that we did together was finished when I was here in California already.
There was one paper I recall — I could get to it quickly that you did with Chandrasekhar and it was published in the Harvard Circular.
Oh, yes, but that was earlier. We wrote a paper on the continuous spectrum of the stars.
Yes. That was in 46. That was shortly after I came back.
Oh, it was that early.
Yes. And there after, at the request of F. Kopal, who was at Harvard doing eclipsing binaries, we calculated monochromatic limb darkening coefficients, I remember handwriting the list, chromatic which was sent to Kopal. On Kopal’s suggestion the list was published in the Harvard Circular.
Oh, that’s how it worked.
That is the way it happened, but after ‘The Continuous Spectrum of the Sun and Stars,” I wrote myself ome more radiative transfer. At the end of the writing of the book [Chandra’s Rad. Tr.] I wrote something on electron scattering. And then he finished the book. Incidentally, the book has two conspicuous mistakes, There are two very long formulae in Radiative Transfer, It is the solution of the finite transfer problem ay1iTWiattering matrix. And there are two long formulae folded several times across the page — where there are no equals sign. (laughs)
I’ll have to look at that,
And according to Chandra that is the only thing I am responsible for in the book, for forgetting two equals signs (laughs).
The only error in the book is yours.
There error is mine. All the rest is his.
He tells you that probably with his tongue in his cheek.
Yes of course. But the theory of the Brightness Fluctuations of the Milky Way contains a little more, I felt, of my contribution.
Well, that was in galactic structure. You’re beginning to get interested in galactic structure.
Yes. In fact, one of the papers in the series was written by myself while he was in India, So I sent him the paper already typewritten and said, “Do you approve it, Chandra?” And he wrote back, “Of course I approve it, I’ll let you put your name first,” So Paper #4 is with my name first, That was 49—50.
During that time you also wrote a paper, a spectrographic study.
Yes, that was in 47 when I took that material.
Yes, well, this is 1950 already.
‘50 I finished it, Well, then Struve must have left in ‘50, because that was very much under the influence of Struve.
Right, you mentioned that Struve and Hiltner were both involved, This s a large gaseous envelope around a star,
He aided the observations?
And he did really. This went quite a long time, When he was working on eclipsing binaries during my McDonald days or when I was a student at Yerkes, he still was working on the binaries. He was very much worried by the fact that some of the relatively mild systems that he observed had very complicated gas currents that were rings around the stars showing very obvious spectroscopic effects, They were mild objects in the sense that there is no large, massive ejection of matter. So he was very bothered about the binary Woif—Rayet stars, And at that time, the Krons discovered this particular star, V444 Cygui, as an eclipsing binary, and they found that it was rather extraordanary because the length of the minima was different the length of the two minima. I was at that time working on the electron scattering, and he advised me, “Why don’t you study that star?” I think he very much wanted me to become interested in it.
He knew that you were appreciating theory well enough to be able to put it to use.
He really wanted me to do it. So he kept on talking about it. Every time I talked to him he said, “What do you think about that?” He gave me the paper of the Krons when it came to him for refereeing. “Study that paper. Tell me if you think it is good.”
Then you were acting pretty much as a referee for the Apj that time?
I used to be a referee, I refereed lots of papers for Struve, lots and lots of papers. It was really incredible how much work I could accomplish at that time. I wish young fellows here would work like that. You know, Chandra used to call me up in the morning on Sunday.
Chandra would call you on Sunday?
He would call me (laughing) to come to work.
Eight o’clock in the morning?
Yes, (laughs) Well, anyway, Struve really wanted me to go into V444 Cyg= HD 193576. It was very much under Struve’s influence, that I went to McDonald to study the star, In fact, we went together to McDonald to observing together, Actually it was a very interesting period. At this time there were two Frenchmen who came to observe in this country. Chalonge, you know, quite a famous scientist in France - was supposed to come with his instrument, a new type of photometric spectrograph. At that time (it was the McCarthys era) he wasn’t allowed a visa, because Chalonge’s brother—in—law was Joliot Curie or something like that. And, you know, Joliot was a confirmed Communist. So he was not allowed to come in at the last minute. The instrument was ready. So they sent a man and a lady Vladimir Kourganoff and Mademoiselle. And the two were absolutely incompetent observers of course, and especially with a brand new instrument, When they arrived at Yerkes with the instrument, Struve told me, “Look at our Colleagues, We cannot trust with a telescope. They cannot observe anything alone. You have to go with them” So we went to the 82-inch .
Well, what was the machine?
It was a spectrograph for his spectrophotometry, a special kind of spectrograph which allowed the obtention of a flat uniform photographic density through the whole spectrum. Its principle was to broaden the spectra in different amounts in different spectral ranges; a gimmick like that. Well, I went to set up the instrument and observe with them. They were I think two months at McDonald. For about two or three weeks we were alone, and then Struve came to observe also.
This was about 49?
49 or 50, But the interesting thing was that by this time Struve was writing this book on stellar evolution. and he already had shown me some of his chapters. At this time we made a seminar in McDonald in which Struve talked about his theories of stellar evolution and the formation of binaries and the formation of the Solar system. And so we had two in attendance, Kourganoff and myself being lectured by Struve for weeks and weeks on stellar evolution. I have some photographs of this which I took.
I’d love to see them.
In fact, I sent the negatives to Harlan Smith at McDonald, because they were taken in the McDonald Library, I thought he should keep them,
At least we know they’re existent.
Yes, I sent them to Harlan, Well, so that was the interest of Struve in V444 Cyg, But I must say also Morgan had quite an influence, not so directly as Struve, in my observational work, Morgans suggestions, amazingly enough, had a very great influence in my life, At the end of 5O I had already been contacted by Greenstein about going to California.
Yes, because everything happened all at once — I mean Struve leaving, Greenstein had left in 48, and within that year of 1950, you left. You must have been thinking about this while you were at McDonald with Kourganoff?
No, I didn’t have any idea really to leave.
But it came up quickly.
At the time I was an assistant professor. I had already had thought where do I go after three years? I asked Chandra. He said, “Well, you have another three. You have six years.” I still had the feeling I’d go back to Mexico. He said, “Yes, it would be great.”
Did your wife care whether you stayed in Yerkes or not?
Not very much. Well, then came the question. I got a letter from C.D. Shane. He said, “We’d like to invite you to consider a position at the Lick Observatory. We have a new 120-inch telescope. Come to visit us.” So he covered my traveling expenses and off I took. I had been at Lick before.
Was this 1950?
No, that was the spring of ‘51. And Just about the same time I got a letter from Greenstein and he said, “We hear you are going to Lick. How about coming around to Pasadena and giving us a colloguium?” So I went to Lick and saw the place and Shane told me, “We’d like to give you a position,” and I said, “Yes, I’d be interested,” and he showed me around, “You will live here and you will do this and will use these facilities.” I was not very much interested. At that time the isolation was dreadful. I really didn’t think it would be viable. Yerkes was bad enough. But then I came to Pasadena.
Did you talk to anybody else other than Shane?
Oh, yes: Nick Mayall. I knew Nick very well. And George Herbig.
Well, G. Herbig was barely out of school.
Yes, but I met him as a fellow at Yerkes.
Yes. D. Popper was, too, for a year, but that was earlier.
Yes, Popper was earlier. And Hamilton Jeffers was at the time in Lick also.
Did you talk to everybody about the possibilities?
Everybody, yes. I talked to everybody.
What was Mayall’s impression?
Oh, Mayall was very much in favor. He wanted me to come. And I thought to accept the Lick appointment mainly because of Mayall although very few other people were at Lick.
Mayall, of course, was going to spend the entire decade building the 120-inch. Was he aware of that at the time? Was he looking forward to it?
I think he was.
Well, you realized the telescope wasn’t going to be there then.
Yes, just exactly. But when I came to Pasadena, Greenstein said, “Well, how would you like to have a job in Pasadena?” I was brought to see the 200—inch for the first time.
Which was in operation.
Barely. So I decided to accept. I went back to Yerkes. By this time Struve had left, so I talked to Chandra and to Morgan. They said, “It’s a great opportunity. You should go to Mount Wilson.”
Morgan said that?
Yes at Yerkes I was told: “You should accept the position in California, in Pasadena, at Mount Wilson.”
Both Morgan and Chandra were supportive?
Yes agreed with that.
They didn’t have any reservations?
Chandra had a little bit of reservations whether I should come. He said, U1 think you are too young yet. You can wait. You’ll have plenty of opportunities. You just have to have a more solid foundation.”
There wasn’t much theory being done at Pasadena at that time.
Nothing whatsoever in my line.
And wouldn’t he have been concerned about that?
That’s why he was concerned. He wanted me to stand on my own. At that time Morgan ee this is the influence of Morgan with two of his students, S. Sharpless and D. Osterbroeck, took photographs of the Milky Way with the Henyey-Greenstein camera the wide-angled camera and made a diagram of the spiral arrangement of the H-II regions in the galaxy. And I remember very clearly when it was decided I would come to Pasadena—I had accepted the offer — he invited me for dinner one night and we had a long talk about what I was going to do here, I really didn’t know what I was going to do here.
This is Morgan talking.
Morgan said, “You know what you should do? Go over the interstellar lines trying to find whether the gas really has a spiral structure like Baade says.” In the H-II regions Morgan, Osterbroeck and Sharpless found sort of sections that looked like spiral lanes just like Baade had found in Andromeda for the HII regions. But as far as the neutral gas is concerned, nobody had found it, of course.
But this was still two years at least before Morgan came out with that paper on spiral structure from the 0 & B Associations.
Yes but Morgan was being very cautious. He had it already, but his calibration was not yet finished.
He was not willing to stick out his nose because of the calibration of the distance scale, that whole thing.
Was he aware that the people at Leiden were going to come out with the radio observations?
No. That’s something rather interesting, because it is also heavily documented. You see, that’s the first thing I did when I came to Mount Wilson, when I jumped into observing like mad, I used to observe 30 nights a year easily. Forty nights a year perhaps. The trouble is that very soon I realized that to find a so called spiral arrangement I had to go to the north and the Palomar Coude was not finished.
That’s right and the 100—inch wouldn’t reach.
Wouldn’t,reach— but very few stars. So I had to wait until the Palomar Coude became operational, which I think happened in the spring of ‘52, or the summer of ‘52. I started taking plates and I remember the at the time of the Rome meeting of the IAU, in September ‘52, I already had the first plates of the interstellar lines in the stars of the doublecluster in Perseus, which very clearly showed the double large scale structure indicating the separation of the gas between the Perseus arm and the Orion arm, At this time, it had still not been found from 21-cm. So I showed these results to Walter Baade together with some of my plates, some of my preliminary shifts, estimates of distances; He mentioned it in Rome, especially to J. Oort, I have the letter from Baade in my files, where he says that he had shown my results to Oort, who was very interested, because the 21-cm survey was showing the same thing. And that was about the fall of ‘52, And as soon as I found this, I wrote to Morgan. Oh, he was just elated with the thing that I had found.
How did he feel when the astronomical community first became aware of the conclusive work of the H-II region studies? I mean: we look back historically and we think well, the spiral structure was first unambiguously detected by the radio work. Is that not correct?
Well, I would say that really the suggestion of spiral structure came out first from the H-II regions, in the sense that these traces of spiral structure as we see it in external galaxies are the bright stars, and the bright stars are associated with the ionized gas of H—II regions. I think that is the definition of spiral structure. If the neutral gas was also concentrated in these lanes was not known, and that would be additional knowledge. But it really was not a known ingredient to the phenomenon which we call today spiral structure. The neutral gas was not the direct observable of the spiral structure.
But the fact that they, too, agreed for our galaxy.
That was very nice.
How did you feel about it when Morgan first showed you his work? Were you aware of this work and of the developing evidence for spiral structure in 1950? Was this a new idea to you, something that you hadn’t been aware of before?
Well, you know, in ‘51 I had already seen Baade’s pictures of the Andromeda Nebulae. He had some pictures in which it was very clear that the H—II regions were aligned just like beads on a string, along spiral arcs. So it was really not very much of a surprise. The similarity between the Andromeda Nebulae and the galaxy was becoming stronger and stronger. Really these strings of H-II regions in spiral arms shown by Baade was the clue to spiral structure in the galaxy. Yes.
Were you very close to Baade in your first years here?
Yes, I was quite close but not in a working relationship, He knew what I was doing, and he used to tell me quite a bit what he was doing. But we did not in any way work together.
Would you say that J. Greenstein was the one that brought you here?
What role did I, Bowen have in this?
You dont feel as if there was an active interest on their part to bring a man who was very strong in theory?
Well, the Mount Wilson Observatory always has been quite separated from Caltech, They were interested in building a department, but I think the interest really came from Caltech; and Mount Wilson said little about it, Greenstein was brought also as a theoretician and was approved by the Santa Barbara Street people0 But after Greenstein came and especially after I came, we appointed anyone we wanted, and it was just a formal approval of the Mount Wilson Palomar Observatory. They didnt have or cared to say much about appointments. I really think so.
So your first large work was on the double lines in the interstellar spectrum.
Yes. Of course, it was completely observational. I had another interest, which was a long interest. Again it came from Yerkes. When I left Yerkes, radiative transfer was gone, stellar statistics was gone and Chandra was studying turbulence at that time. And, of course, that background gave me the idea of studying some day astronomical turbulence, whatever it is. And just about that time came out a paper by S. von Hoerner in Germany, on the spectrum analysis of the motions in the Orion Nebula on the basis of the turbulence theory that had just been developed by von Weizacker and Kolmogoroff. So one of the programs I brought when I came here was to study from a pure observational point of view, the observational basis to study properly theories of turbulence in astronomical gas masses, realizing that the data that von Hoerner had at his disposal had left really much to be desired in accuracy and completeness.
So the idea was to improve the data.
Improve the data, And that was perhaps even more pressing to me, because it had something more to do with my theory of the moment.
The interstellar medium literally.
Yes, but the turbulence, And so when I came we started planning to do turbulence. It happens that both Baade and Minkowski had worked on that subject many years earlier.
I hadn’t realized that.
Yes, They were one of the first ones to study line width variations in the Orion nebulae many years ago in Hamburg.
The problem of understanding turbulence — could it also be involved with some of your on-going studies of the interstellar medium itself? Later on you identified high velocity small clouds, and you were talking about turbulent velocities at that time — were you not?
Thinking of the clouds as members of the galaxy and turbulence within the galaxy.
At that time, of course, really we did not. Some people had already attempted to study the multiple structure of interstellar lines in tenns of turbulence. For example, Unsold wrote a paper on that. But my interest in turbulence was really as applied to emission nebulae. That was my real interest.
I remember the paper where you did study expanding motions in M—3l
But that was 1960 already.
The really big paper the enormous amount of work Olin Wilson and I did on the Internal Motions in Orion Nebula was the result of interest in turbulence theories.
That was in the early 50s?
Yes, It took us about five years to do that job. It was a really incredible piece of work, I mean the volume: I never could dream of starting anything like that again. It was an enormous piece of work. We measured 50,000 radial velocities.
These are radial velocities of knots and whirls.
Yes, every second of arc in the Orion Nebula. In fact, we measured so much that I think on the way the theory was lost - (laughter) overkill. We discussed the theoretical problem a little bit. I myself discussed the interpretation in a paper, not very well known, which appeared in REVIEW OF MODERN PHYSICS, on an issue dedicated to the second symposium on cosmocal hydrodynamics —It was then—when we came to realize that there were some fundamental problems in trying to understand the motion in the nebulae on the basis of conventional turbulence theories. We encounter fundamental problems in the interpretation and I think for the first time again we suggested that turbulence in the nebulae more like a system of shock waves propagating all through the nebula.
Was this about the same time that Oort and Spitzer came out with their dissipation work?
That was a little later.
So you did this work before that.
Yes, we found evidence for shocks in the emission nebuale but the question of what drives the shocks and what keeps the gas always stirred up keep on unsolved. Well, we are still working on it. At present I’m writing a paper on the effects of stellar winds on the nebulae in which stars are imbedded, and I think that may explain “turbulence.” But to realize this has taken more than 20 years. So still I’m working on the same lines.
This gives me the impression that you’re getting closer to stellar evolution in this kind of a problem because you’re talking about the production of these shock fronts might be produced by the first stars that are formed — the Trapesium stars or something like that—out of the Orion nebula. The shocks wouldn’t have existed before these particular stars formed, the most massive stars at least.
Yes, that’s true, That’s still an open question. You see, there are many problems. If we find out that actually these stellar winds, high speed mass ejections from stars, are constantly stirring of the nebula, we could use the degree of turbulence in the nebula as a measure of the wind activity. But it still remains to be proved. Indeed, it should be followed, because that would be very important if true. That’s in the future. So it would appear that I am still working on the programs which I brought from Yerkes, The problems of the turbulence in the emission nebula and the interstellar lines occupied the first ten years of my life here. I did’t do anything else. Well, I did small things on stellar atmospheres, but not very extensive.
That first ten years then would be literally the 5Os.
The ‘5Os up to the beginning of the ‘60s.
I know in the early ‘60s you started doing some planetary atmosphere work.
No, the first planet work I did was in the Mars opposition in 63.
Yes, that would fit, Did you find yourself getting more and more interested in cosmological questions? I know you started doing some extra galactic work, mass luminosity functions. What pointed you in this direction simply the capability of the 200—inch or contact with A. Sandage?
No, I never had much contact with Sandage. Sandage was a student when I came here, and I never really had. I was going to say enthusiasm. I never believed in cosmology. (laughs) Its something to believe. I believe in abstract cosmology in the sense of general relativity, the basis of cosmological theory. But observationally you have to believe in it, because its so full of holes. (laughs) I never was convinced by it, put it that way. To do studies of spiral nebula,- that’s completely different: study the dynamics, study as an entity the distribution of masses, the distribution of chemical composition or the formation of different types of stars in different stellar dynamic systems or sub—systems. That’s fine, But I really wasn’t attracted to cosmology. I really never liked it.
Or distant cosmology. What about the trend now to study galactic evolution? This seems to be a more finite problem.
Yes, Again I never have gotten very much involved.
Yet you did do a few studies of the faint end luminosity function of external galaxies, trying to determine the number of dwarfs from the color characteristics, What brought you to those problems? These were done in the ‘50s.
I never did that.
Well, let’s see: this was 1959-PASP Mass Luminosity Ratio. Did I misinterpret what you did?
No, but I didn’t do color stuff. Yes, I mentioned the colors. You are right. I mentioned the evidence from the colors. But the problem is still unsolved: where is the missing mass?
That’s right. You seem to have come to that problem of the missing mass from two directions. There was one direction, but the other is with this work that you did on high velocity small mass clouds. You were finding two types of interstellar clouds in our galaxy.
And you were asking a very important question: how do these clouds remain stable, and you brought forth the Spitzer-Oort idea of a hot halo. Now, how does this all fit into the missing mass business in your mind? Did you have that in mind as you were doing that problem?
You know, it crossed my mind once, I remember, to put the missing mass in a very big halo, but you can show immediately that it doesn’t work. It Just doesn’t work. The only thing that works is to have the mass in the form of baseballs.
Literally Just in terms of dark mass?
In terms of rocks, not very small and not very big. That would do it.
Too big for grains?
Too big for grains, yes.
And too big for polarization.
Yes, that’s right. And the ratio of mass to surface goes up very fast. So I think the question crossed my mind, but I don’t think I thought seriously of following the matter on that line.
Well, with your philosophy then steering you away from cos mological questions, as you look back over the ‘50s at Caltech. What was happening administratively at Caltech in terms of the priorities of these different types of problems that were attacked cosmology as opposed to stellar astronomy? What are your recollections and feelings about the direction of astronomy here at Caltech during that period? I’m saying Caltech but I mean the observatory, of course.
I think that there was within the directorship mainly some sort of unwritten list of priorities. An inheritance from George Ellery Hale transmitted by Hubble.
No, not Adams, but through Hubble, The largescale distribution of matter in the Universe, revealed by the faint Galaxies and clusters of Galaxies always had, with reason always priority at the 100 and 200 inch, From the observational point of view I think the most remarkable thing is that shift distance relation. It is incredible, Nobody cheated to make it linear, but it was incredibly too good to be true, because the world is not linear, So that was the motivation of the 200inch. And for many years in the ‘50s that was the motivation for the whole support of the 100 to 200inch, primarily. Most of the primary observing time to Ninkowski or to Humason to get some more points in that famous diagram, I did not take part in that, In fact, officially I never had any dark time, I used to do my extragalactic observations on the ends of spectroscopic nights or the beginnings of spectroscopic nights.
Did you have any ill feelings about that?
No, not really. I really was very much interested in what I was doing, (laughs) No, I didn’t really have any bad feelings about it. So it never really crossed my mind to go full time to do galaxies. And I still think today that I would not have done it. I never thought of a good way of studying the problem. Our methods are too coarse to really find something meaningful.
Do you think today, though, with the different reduction procedures and the isophotal contouring procedures we have now for studying galaxies that the problems can be better attacked?
I have my doubts.
You don’t think the advances in instrumentation have made that much difference?
It has made a lot of difference. You can study more, you can do comparative studies much more accurately; but I still don’t see any basic thing coming out as to what are these things, and why does ‘it’ happen in that way? To me nothing in galaxy research was so important as the recognition that there were galaxies. That is the first and the last important thing that has happened. That’s it. That’s the only thing we know, that there are galaxies. We don’t know why, how, what they are made of. There are lots of ‘hand-waving motions’, what are the formations? Why are they segregated? There is nothing really solid that we know.
Do you think that the basic ingredient of a galaxy, though, is ‘to understand a galaxy is to understand its interstellar medium’ by any chance?
It’s a very important thing. It’s a very very important thing. And still we don’t know the answer why some galaxies don’t have any interstellar matter. Did all of it go into stars?
What do you think of the stripping mechanisms that people are playing with and the ram effects? What are your opinions regarding those? Are they too catastrophic or what?
That’s a long, long, story, and we knew it in the 1950’s; it already was being mentioned.
Tidal stripping, galaxies colliding, all of these ideas.
And you don’t think they’re going to be too fruitful, these mechanisms?
I’m not convinced that everything can be explained that way. A lot more work needs to be done. You can explain interacting galaxies and you can explain how you can clean a galaxy out of gas. But I would like to see the statistics really satisfied about the number that we see plus the number of stripped big spirals. Does it really fit with the number that we considered stripped? I don’t think it really has been shown.
Well, am I correct in assuming that Minkowski was the guiding force behind the Palomar sky survey and all of the galaxy counting that had gone on here?
Yes, he was the executor of the project. He really coordinated the project to completion. But I think the motivation for building the 48inch Schmidt is before Minkowski, In fact, I think it probably goes back all the way to George Ellery. Hale. W. Baade had a lot to do with it, because he was a personal friend of the inventor of the Bernhard Schmidt system. Baade he had a lot to do with convincing Hale to get money from the Rockefeller funds to build the 48inch Schmidt. Minkowski also had known Schmidt, and he was who first intro duced Schmidt cameras into spectrographs and thereby convinced Bowen to do the same in the large spectrographs, although Ted Dunhm also did something like that earlier, Schmidt camera in the Coude spectrograph. I must explain, however, that Minkowski though, was not their never did galaxy counting. The only largescale galaxy count and cataloguing was done by Fritz Zwicky, although he was completely isolated from anybody else.
Was this because of his personality pretty much?
Yes. He was very much on his own. In an earlier stage he had a lot to do with Walter Baade, but again two strong personalities very soon clashed and they stayed afterwards alone by themselves,
Lets talk about the development of the graduate program in the 5Os. Greenstein directed the graduate program at the observatories, Were you involved in the teaching?
Oh, yes, that was my main job. When I came in ‘5l Greenstein and I taught everything. Zwicky never taught anything.
Did you do teaching at Yerkes?
Yes, some small amount, Yes, I helped Chandra with stellar at mospheres, and I went sometimes down to campus and gave some lectures.
How did you feel about teaching in general? Did you enjoy it?
Yes, because I really started learning a lot of things that I had missed all the way through, (laughs) When you had to write a set of notes you began to realize how much you are missing and especially when the students start asking you questions. Then its really embarrassing.
Did you find the students at Yerkes and at Caltech here of similar caliber?
I would say so. Probably the students here were better, here in Caltech, but it may be a ouestion of time When I arrived here the students were A, Sandage, H,C. Arp, George Abell, H. Abt , , And I used to give all the theoretical courses here: stellar atmospheres, stellar interiors, stellar dynamics. Then we got Osterbroeck and Code to help us . . . I brought them really because Greenstein didn’t know them. They came in ‘55, ‘56. And then we had a bigger group.
Okay. Arp and Burbidge were listed as research fellows; Sandage was here. Was W.S. Adams still around at all? He died in ‘56.
He was around, yes. I saw him. I saw him several times. When he retired he used to go to the Hale Tower, where the retired people go to die.
I don’t know this. Is this a legend?
That is the Hale Tower. Hale had a solar tower in his own private house.
I didn’t know that.
Yes, near campus. You must go and see it. Besides building 3 solar towers, 2 at Mt. Wilson and one at Caltech, Hale also built one at his home. And that tower was used as an office for retired people.
Is that still in existence?
The tower exists but it’s not used as an office anymore. The tower is a working tower, yes. It’s in existence. That was his home, but he willed it to the Carnegie Institution. It’s in San Marino. And what was his house was sold separately. It finally belonged to his daughter, and then his daughter sold it, but the piece of land which was in the back where the tower now is a different piece of land and belongs to the Mt. Wilson observatory. It’s still there, yes. They closed it because of vandalism.
That’s too bad.
Some of Hale’s old papers are still kept there. It really was his own thing.
Let’s get back to the teaching because I know the teaching is very important. How were the courses organized? Was there any committee or a group amongst the faculty that would sit down and decide on curriculum and priorities in the curriculum?
Essentially Greenstein, myself.
Did the other people not care or what?
No, that’s all. We were the only two teaching people.
There were only two from the Hale observatories who were at Caltech.
At Caltech. Now, of course, we went to the faculty of the physics division and there were some requirements in physics and extra work. We didn’t organize it within the division.
Is it a coincidence that the only two people, you and Greenestein, who had anything to do with teaching at Caltech also were strong in theory?
Yes, I think there’s no question.
Is this what Caltech wanted?
That’s what Caltech wanted, yes.
Well, how does this then fit with cooperation between Mount Wilson/Palomar and Caltech? How was the relationship during the ‘50s? How did it develop?
Without saying so, I guess that the Caltech people realized that the observatories were weak in theory.
And did they feel as if they were in a position to tell them that they had to strengthen it?
Well, I think they tried to tell them that they should try to build it up. You see, at that time the observatories were at the tail of the Hale age. There was not a single young man. The youngest man was Horace Babcock with exception of Olin Wilson, all the rest of the Mt. Wilson staff were of the Hale epoch, so they really were quite old. The only man that was brought during those early years was Annin Deutsch, who also was from Yerkes. We were students together, of course. So really in the early days and specially we brought Osterbroeck and Code all our Caltech staff was transplanted from Wisconsin. Osterbroeck and Code, together, left us in ‘58 to go back to Wisconsin.
Was there a reason for that?
Yes, there was some reason. Of course, Code wanted to have his own place, as he liked to be alone, and he liked Osterbroeck and he convinced him to go with him. And there was some degree of misunderstanding between Don Osterbroeck and some people at Santa Barbara Street, and I think that was a very great loss to the observatory to let Osterbroeck go.
So most of these misunderstandings, as were talking about them, were purely internal in the observatory itself, They didn’t deal with Caltech.
No, it was very sad. I don’t know how it happened. He never told me really.
This was with their leaving.
Osterbroeck, why did he leave, yes. I could understand Code, but I never could understand Osterbroeck, and I was very close to him and asked him, “Why are you leaving?” and he gave me reasons like the smog and I said, “Thats crap and you know it.(laughs)
The smog he said?
How many students did you have in the ‘50’s?
In the 50’s actually I didn’t have a single Ph.D. student. I took a year leave of absence in the year ‘58 and I went to Germany.
That was at the Max Planck Institute.
Yes, when I was going to study turbulence.
Oh, that’s why you went there.
I wanted to think about turbulence, yes.
Did they offer this year to you?
I’m interested in how people get positions.
What I did here was to tell my chairman that I wanted to take a year leave of absence, in order to study what I was doing, “Where are you going to get money?” he answered me, So again I wrote to the Guggenheim Foundation and also I applied for a Fulbright Grant and I wrote to Germany: “Could I be accepted?” Yes was the answer. So I went to Germany and I stayed in Heisenberg’s Institute for a year. It was rather an interesting experience actually, because it took me back a little to theory, and I met some different kind of people with different points of view, I enjoyed my stay away from Caltech for a while very much and I entertained the idea of staying there. The opportunity to do so was offered to me. This was in ‘59.
The year after that you were in Leiden.
No, I spent only three months in Leiden. During my stay in Europe I went to several places.
That’s when you worked with your brother on the O and B stars.
What happened when I came back.
Okay. Well, we’ll talk about that in a minute. But what was your decision to come back again from Max Planck? Obviously you were drawn to the conditions there for research, and you obviously liked theory.
No, actually they wanted me for something very different. At that time they were beginning to consider the possibility of building a large observational facility, a national German observational optical facility. And they wanted me to help them. After thinking about it I turned the offer down. I couldn’t accept because my children in this country were too young. And I felt also that I was not old enough. I didn’t have enough weight to swing around.
Political in the internal morass that is the German akademia. Germany akademia is something special. So I came back. On my return I started to have Ph.D. students. I had quite a number. In fact, I took my first student probably just after I came back in ‘61. Since then I have had 16 or 17 Ph.D. students.
You also had a number of people coming as junior scientists visiting and studying with you.
Yes, not really many, though.
Well, you did work with H. Spinrad, and this was when you worked on Mars.
Yes, Spinrad. But he worked at JPL.
At JPL I worked with Spinrad and also with Gerry Neugebauer. who eventually came to Caltech and with whom collaborated extensively But I never really organized a large project. Perhaps I was sort of afraid to run projects with many people.
You were acting as a NASA consultant at that time.
Yes, I was very much with NASA, yes, in all sorts of projects. But at that time it was easy to get money. I always was thinking I should I get more telescopes, get more people. But I didn’t want to get too involved in it, because I was involved enough so that most of my work was with planets anyway.
What drew you to that kind of study? Again, was it radiative transfer? Your study of the water vapor content of Mars I’m interested in.
Well, that was, of course, what started the whole thing.
Had you read the early papers by Adams and Dunham?
Yes, very much and Kuiper’s also.
Did you go even farther back to Campbell, Lowell the big controversy they had?
No. I knew of the controversy, but I didn’t dig into it. The Adams and Dunham paper I was very much aware of. By this time I already had enough knowledge and familiarity with the spectroscopic instruments that I fully realized what was needed to get through beyond then.
You were pretty sure then that they were still pretty far off the mark or did you just figure that it had to be resolved to a better degree of accuracy? I mean did you think that the quantity of water vapor and oxygen they were finding Adams and Dunham and then St. John was too high? Or did you just want a refined value?
At that time I realized it could be done better; that was the point.
There was nothing else that made you think that maybe they were finding far too much water vapor or something?
Yes, I think they did.
From a theoretical standpoint.
Not from theory, no. My whole idea of tackling that problem, came from conversations we had after Mariner II had flown by Mars in 1962. And I had talked over the problem with Neugebauer and with Lewis Kaplan and Spinrad. Spinrad had attempted to take some plates at Victoria, which were inconclusive because Victorias atmosphere was too wet, And he asked: “Why don’t we get some plates with the 100-inch?”
Did you get in contact with him or vice versa? I mean how did he get to JPL? Was it through you?
No, after graduating from Berkeley he began working at JPL. Used to go to JPL at that time mainly I think because of money, They used to pay me to go there.
Well, you were a consultant.
Yes, yes. So Mars was not really my interest, but I had already been interested from the point of view of radiative transfer, and also the old Herzberg influence of his work on the major planets. Herzberg’s work on Uranus and the pressure induced absorption. By this time (1962—63) I already had read papers on pressure induced absorption. I was taking plates of Jupiter. And I had already the idea of building an abstract model for Jupiter. Working around the observational constraints, The Kuiper model was done purely empirically and he could not establish why it worked that way. He didn’t know how to hold the heat.
Were you still working from turbulence?
No, this was only from radiative transfer to make a greenhouse with the pressure induced absorption of hydrogen. Nobody before really had realized how important it was. flow, I gave it as a thesis to Larry Trafton, who is now at McDonald, And at the time of the 1964 IAU meeting in Hamburg we already had built a model, about which I presented a paper describing a completely self-consistent model in radiative equilibrium of the Jupiter atmosphere where the source of opacity was the pressure induced dipole absorption.
What was the reaction to that paper?
I don’t think it really filtered down until it was written in full length form about two years later And by this time the interest in planets had grown to such an extent that immediately it was taken up by many people. I should have made more noise about it. I don’t know why I didn’t. That realization that pressure induced dipole absorption was producing the greenhouse effect in the major planets, the hydrogen planets, really was one of the nicest thoughts I ever had, because it really was made from first principles. Here is a problem that nobody had realized. Everybody knew that hydrogen was the major constituent and said, “But hydrogen is transparent.” And people attempted trying to build greenhouses like the great old man Opik, who tried to make greenhouses with CH4, or NH1 which do not work. So that really came out very nicely. That was ‘54. The self- consistent model obviously is worked. That that was not enough. We really had to prove that the model was correct. I had the idea of proving it for a long time but really we did not have a chance until we proposed for the Pioneer space craft. Our radiometer for the Pioneer 10—11 space craft package was designed to make a color measurement which would reveal the pressure of H2 pressure induced absorption. It took seven years until we really could prove our model. That is why I consider this experiment was one of the nicest things I have done.
That Pioneer experiment, taking seven years like that, that pretty much put you into space astronomy.
And I was just wondering how you felt in that interim. Was it a very anxious period or did you just let it sit?
Well, no, there was no chance to do it, so I just let it sit. I took more plates of the major planets, and I did some other work on the major planets, but nothing particularly exciting I think because they are difficult problems. But my entry into planets taught me a lot, I learned a lot. And the structure of the major planets is quite interesting. It’s quite a productive field. I’m sure that had I stayed in stellar astronomy, it would have been much more flashy in doing galaxies. I do not regret to have stayed working on planets for all these years. I’m more convinced than ever that there are some extremely important solar system problems that are still waiting to be solved, very difficult observationally and theoretically.
What do you think they are? Do you think there’s still a problem with the origins of comets or something of that order?
No, I think the problems are more basic than that. We really do not understand the evolution of the atmosphere of the terrestrial planets. Now, that may be a question which has too much chemistry involved and it’s beyond my grasp because I don’t know chemistry. But let me jump into what I’ve really been concerned with for the last few years. I’m concerned with Jupiter. If you really study the Jupiter system, it’s more than a planet; it’s more than a star that generates a small amount of heat, It’s much more than that. You really see a complete closed system, a planet which really has very little to do with the sun, the solar wind. It has an enormous magnetic field, We know unquestionably that it accelerates particles to cosmic ray energy through purely internal processes. It is a closed system with a very low luminosity.You know, l50°K degrees; that’s nothing. Most of the heat we measured derives from the sun, but nevertheless somehow the planet manages to maintain an activity characterized 20 or 30 million EV protons, which is really very hot indeed.
Were you very surprised when Pioneer went through the magnetic sheath?
Well, we knew there was a magnetic field but we didn’t know how extensive it was.
It really was a lot more extensive than we thought.
Oh, yes. And now what we are seeing, For example, I am absolutely convinced that Jupiter now has an envelope that must have something like a solar coronal gas of million degree gas. And in some way, there is still really a lot of work that can be done from the ground. From the classical telescopic way.
Are you going to be asking questions like what supports that corona? Are you going to look for analogues from the suns acoustic support?
Yes. And times, lifetimes, how do particles get the energy.
Yes, it certainly was a remarkable observation when they realized that craft was being bombarded with all of the particles.
Yes. And our instrument was never supposed to be a particle detector, but it became one. We could send commands to change our data taking cycle to the different directions which our small telescope was looking at. Before going into occultation behind Jupiter Pioneer II was commanded to point to the direction that we would see after emerging from occultation, But when we actually received the postoccultation signals, after a travel time of 40 minutes, we established that our telescope was wandering about under false commands induced by intense particle radiation.
People were very excited about that, Were you at JPL actually?
No, we were up at Moffett Field, As I said before, soace work is very unproductive, you know. Its an awful lot of work for what one has to show at the end. The amount of effort that goes into pr& paring the smallest kind of experiment is incredible,
Is this your first direct association with creating in strumentation in order to do problems?
No, not from the qround. I mean I had been doing instrumentation, I became something of a gadgeteer I suppose at the end of the 6Os. But I had already been associated with several planetary projects, not as a principal investigator. I worked on every Mars probe after Mariner II in 67, 69, 7l and now in our Viking, which I was related in a remote way, I tried to stay away as far as possible, as I could.
What about the space telescope? What do you see for that future?
Oh, I think it could be absolutely incredible fantastic. I have not proposed any kind of piece of hardware of my own, and I have no proposal to take any part in the project at all. I have a small proposal on a filter, but it is so small that I believe they will let it ride. I’ll be too old by then, but I certainly would like to be something like a guest investigator. You see, I don’t really want to take the responsibility for any of those bloody things.
That’s the interesting question. It seems like some people are talking about setting up an entire institute much like the National Observatory.
That’s what we wanted, yes.
In agreement with this kind of a philosophy.
Yes. I was on the Physical Sciences Advisory Committee when this question came up. And this came up because of the enormous success of the Lunar Institute. We believed that if people go home and take the data, they put it in a drawer and the data is never heard of anymore. And for an instrument of this cost and this effectiveness, we need the data to be analyzed almost in real time to feed it back to the telescope. Otherwise its a waste of time. We’ll be accumulating, accumulating, data, and it is not like a telescope on the ground. I may come back to Palomar one year from now and the telescope will still be in the same place. But in space we must have feed back within weeks. We have therefore to capture scientists and do not allow them to go to the corner. We can not stop the tapes from being filled by data. It’s the only way to work.
I’ve heard stories about banks and banks and banks of tapes sitting unread at NRAO and other places like this. Has this been the kind of thing that people have been worried about not duplicated?
So then a tremendous amount of support has to be available for reduction.
An instrument that sends data 24 hours a day and cannot be stopped: there are no astronomers to study so much. That’s my real worry, Where are we going to get the astronomers to study all that data? Computer power and all that is easy you can buy it, But astronomers who are going to digest the data, think about it and write intelligent papers rather than long, long catalogues with numbers, the problem worries me. where are we going to find them?
Thats an interesting observation.
And a very very difficult problem to solve also, I have raised it at NASA headquarters, and they just shake their head. I have asked why they have cut all funding for NASA traineeships for graduate students. The NASA university program is essentially finished.
That was the question basically you asked them?
Did they give you any answer at all?
Not really. They said it was a question of policies and A & B decides things. That education should depend on the National Science Foundation funding.
I have a few questions. I’d like to go back into the 6Os. The study that you did with your brother the radial velocity of the 18 OB type stars where you find a high rotational velocity from stars and that is found from 2lcm work for the galaxy, the inner parts of the galaxy. This sort of gave us a different value for the Oort constant of that time, and I know just from general reading that the value of the Oort constant at that point was very much in question, This was A— The Oort constant A. What was the general feeling on your part and on the parts of people that you talked to about how this problem was going to be resolved or is it even resolved today?
This is a fundamental question of the scale of the galaxy.
Thats correct. Well, I really didnt stress the point too much.
In the paper you didn’t.
But I know that that’s an important element in it.
There is a real limitation on the size of the sample.
There were 18 stars at that time.
And there is a strong selection towards the brighter ones. When you don’t have a complete sample, there’s a very serious bias.
Well, what is keeping you from collecting more data? Telescope time?
No, no. The data we had at the time referred to stars of different classes and different nature. I think now it would be done better. First we have to find the stars. At that time we couldn’t go beyond the limit we could reach do with the small Schmidt cameras that were available. So we struck at the 12th magnitude and that’s enough. It would have been worthless to go to fainter, because there were no spectrographs to reach fainter magnitudes at the time.
Well, you had to find these stars.
We had to find those stars.
Did you do that by ultraviolet continuum searches?
No, just classification on objective prisms. And that’s what my brother did. He did a survey of the whole southern Milky Way. Soon we shall have an objective prim in the 48inch Schmidt. They have put an objective prism in ESO. Probably we could push two or three magnitudes today. And with the new digital spectrographs there is no question we can do much better. So I think we could do the problem so much better today that it would not have paid to continue photographically ten years ago.
It would not have paid.
It would have been very arduous and long work, hardly worth it. But today it should be done.
Are you aware at the time you’re working on various projects of these kinds of elements the cost efficiency of doing the project and whether it might be done better in the future? Is that always a factor in your choice of same project?
I think it is because I’ve never been careful enough. The question is: how much time you have to put into it, because a lot of it is your own personal effort. And say how many hours do you have at your disposal? You have to teach and there are five papers in your desk, waiting to be finished, and are you going to generate another five papers?
There are only so many hours in the day.
Well, do you work 24 hours a day?
What do you do when you’re not working?
I find myself, especially when there is some work I can do like writing without too much pressure, but something which is (different). I have had occasion lately to do heavy algebra, really heavy algebra, programming. I do it five hours and I go out of my mind. I don’t want to see it one minute more. Forget it — it’s impossible.
This is pretty much where I want to be right now in talking about your philosophy of research and about your personal life. You’re not a 24 hour a day person, or are you when you’re up on the mountain? What do you do to relax and unwind?
But, of course, it is very hard to unwind. I mean when you have a problem, you go home. You say, “I won’t stay in my office I have a home.” But you keep on thinking about the same thing, playing with it and you get up with the same thought. It cannot be helped. And personally I don’t have any strong hobbies except playing the guitar, occasionally; listening to music, reading history, art and literature, and exchanging ideas with my friends or anything that can distract my attention. Sometimes I do manual work around my home, but I keep on thinking about the same thing.
What about your children? You have four children.
That is correct.
Are they all at home?
No. I have one who is in atmospheric physics. He’s going to get his Ph.D. degree probably next December. He’s at the University of Seattle in Washington.
His full name?
Charles. He is, as I say, in atmospheric physics, and he’s very much interested in micro turbulence in the atmosphere.
Oh. I wonder why. [laughter]
So he’s going to teach me all about it. And the other two following are not interested in academia. They left school and they just survive. And the young fellow apparently is interested in some creative work. That’s it.
How old is he?
He’s 15 and he’s a movie maker. He just got a prize. His little movie was on national television. Hopefully he will go to school. He wants to go to school.
Do they usually find their father at home?
Well, this is one of the difficulties. You see, I was divorced, and I have been remarried and now I’ve been living in Europe for the last year, and I am going back to Europe, and I think I am going to stay in Europe.
You mentioned you’re going to Heidelberg.
Yes, I am going to Heidelberg. And I think on the first of January I am accepting a position in Germany, and I will stay there permanently.
This is a surprise. Can you talk about what has caused you to make this decision?
Well, a little bit. You know, it’s a follow-up on what I mentioned earlier. In ‘58 I met — Reimar Lust— who today is the president of the Max Planck Gesellschaft — and who is a good friend of mine. In ‘58 he insisted that I stay. And I didn’t stay because I couldn’t afford it. But over the years they have had their programs going on, and now the large astronomical observatory, the German national facility, is a reality. It’s almost built. And for the last two years he has been after me, and he told me, “Now you have to give me another excuse.”
Was there anything happening here between Caltech or between Mount Wilson-Palomar? The general trend in the United States which makes it a little less conducive to you to stay?
Yes, to some extent I think there has been a change here. I think the resources of the observatories are going down every day, of Hale Observatories. And it has become almost a question of survival of different groups. We don’t have a coherent picture, a coherent plan of how we’re going to survive. There has been a lot of friction between the Carnegie people and the Caltech people, which I dislike very strongly. I think if they separate, that will be the end of the observatories.
Is there talk of that?
There was some talk about it about two years ago.
Have you been involved in that?
No. There was some talk actually, and finally the staff, when they knew about it, almost rebelled against this,
Who instigated it?
Well, that’s something obviously high up.
And you don’t know. Was it Carnegie or Caltech?
It was on Caltech’s side, but it was somewhat instigated from Carnegie. I think the policies of Carnegie are a disaster, The most disastrous is the building of the Chilean telescope, the Las Campanas telescope, the 100-inch, without resources.
No instrumentation money?
No instrumentation money. You can not start making a 100—inch telescope with no money.
Was the money originally available and then they took it away or what?
No, $5 million were available but it’s not enough, even if carefully planned, I don’t think we need a 100-inch telescope at Las Campanas. We never were consulted on the matter, Babcock decided that Carnegie would build an Observatory at Las Campanas with a 100-inch telescope which was not part of the Hale Observatories until a year ago, Its crazy.
Babcock made this decision on his own.
I am convinced very much on his own. He has made his own monument there. There’s absolutely no point. The southern hemisphere is full of telescopes. We could have used those funds $5 million to make the 200- inch telescope what it should be.
With support instrumentation.
I guess its apparent that people from Hale Observatories are showing up at Kitt Peak to use some of the instruments there, Is this sort of…?
Well, the 4 m. telescope is a very remarkable instrument in some ways.
With the 200, you could do the same thing, couldn’t you?
No, I don’t think so, no. The 4-m has unique optical qualities which the 200-inch does not have, and we never could make it here.
Oh. It’s not just the auxiliary instrumentation.
No, no. The auxiliary instrumentation we have is as good as Kitt Peak, We have managed to keep up in certain fields but not in other fields. I think the observatories are literally falling apart. I really am very pessimistic about the future here. Not in a selfish way. Don’t misunderstand me, The general scientific life of the observatories I think is about to disappear. I think we are bound to become a national facility. That’s the only solution here.
This would be used then much like Kitt Peak, Well, you’ve always had a very generous guest investigator program here, haven’t you?
Yes, we still have. We have encouraged guests and we have quite a liberal policy, which is at no cost to them and we don’t get a penny from any federal sources. I’ve always considered it to be eminently unfair.
To us, yes. Curry gets money from the National Science Foundation, the fellow you saw at noon. He comes from Ireland, flies in his own computer, four tons of equipment, four assistants. He uses the telescope for free; he doesn’t need one inch of anything— we give it to him. When I ask for money from the National Science Foundation for equipment, I put it in the telescope and everybody uses it, The National Science Foundation doesn’t recognize that. They don’t give us one cent. The Kitt Peak people who are at Kitt Peak (send) proposals to the National Science Foundation. The proposals are never referred by anybody.
I’m sorry, what?
The proposals for the Kitt Peak people are referred by the special department of the National Science Foundation. Our proposals are referred by the Kitt Peak people.
That means that the people at Kitt Peak have primary control of all the money that goes to astronomy.
Exactly. And that’s a very unhealthy situation.
How long has this been developing? I mean was this the intention let’s say of building a national observatory, that the government would then generate a body that would have primary control?
No, it was not the intention, no. But with the shrinking of the monies of NSF there has been a tendency to concentrate all the support into what is the most important, the more expensive operation at the sacrifice of the small people. And since we can have only small grants, they cannot give us institutional grants.
Because of the Carnegie support? Is that the reason why?
No, because it’s a federal policy. We have a national observatory; we cannot give you institutional support.
Because they support the national observatory and institutions.
Yes. And so the small grants have been shrinking and it’s impossible to get small money. But I don’t blame the National Science Foundation. The real people who are at fault are the Carnegie people. There’s no reason to go spending endowment money making a telescope 6000 miles from here.
They are spending capital?
They are spending capital money to run the Carnegie Institution of Washington, and you know that doesn’t last very long.
I didn’t know that. Was that a policy decision?
Could he have stopped it?
I doubt it. He wasn’t in control of it.
What do you think could pull the situation out?
I donut know, Abelson is leaving.
From Carnegie. Oh, I didn’t know he was leaving.
Next year. His successor is a man from genetics. He has been picked already, and we don’t know the gentleman. In fact, I think today he’s in Pasadena. And Horace is leaving; Babcock is leaving the first of July.
Retiring from the directorship?
Is that a premature retirement or is that regular?
Regular. He’s 67 years old. So we don’t know what’s going to happen, but I’m very pessimistic about the place, what’s going to happen and scientifically whats going to be.
When will it become known that you are leaving? Or have you not made a definite decision?
No, I have made a definite decision, yes, I have to send my resignation, but it’s understood I will leave on the first of January.
You’ll be going soon, to Heidelberg, I understand.
Oh, yes, I’m going back next Sunday. I have a leave of absence right now.
You are on a leave of absence. You’ll you be coming back before then? Because there may be some reason for us to get together again.
I will be here the month of December.
That’s tough for us. And then you’ll be in Heidelberg for good, literally; but I imagine you would still be traveling to the States for meetings.
Will your children be staying here?
Yes. They’re all pretty old. But the youngest probably will come with me next year, as soon as he can speak the language a little bit.
Yes. That’s a good experience. How about the skies in Germany?
Well, the sky is absolutely rotten. It would be insanity to make an observatory there. The observatory is in Spain, southern Spain. In the Sierra Nevada near the Mediterranean. It will be a large facility. The largest telescope will be a 3.6-ni. It’s not a 200u, but it’s a pretty large telescope — 140-inch. And there is a 90-inch, which is up, and a 60-inch, which is up already.
Do you have any qualms with dealing with Spain in its present state, or do you think that it’s getting better?
Well, of course, when Franco was alive, I should have had qualms. I wouldn’t have gone, period.
I was wondering, yes.
But I’m sure there won’t be any trouble. The Spanish government actually have turned over. The amount of money they are pouring into the universities and into science is incredible.
Oh, that’s great. I didn’t realize that. So this is a move to a situation that looks as if it’s improving.
Yes, I don’t have any qualms about Spain, about the fact of the site being in Spain, in the country. I think it will help us. And of course there are always some questions to ponder about how things will go in Germany. My friend is the president and he can do whatever he wants, but you wonder how long is he going to be president and then what happens?
Yes. Well, the economy in Germany is in excellent shape right now.
But again you wonder: how long is it going to last? You know, there are pressures to re-evaluate, to do whatever they do. Employment can go up, go down. It’s complicated economics. But they really have very good backing. I mean, essentially, the financial backing has come up to the point that it’s an obsession with the federal government of Germany to bring German science into some sort of a position resembling what once it was. They will do anything I mean, to them its really an obsession, Its no longer a question of national pride. It’s just an obsession to them.
I don’t know about their motives, but that certainly can help science in a general respect. I imagine you do have to consider these kinds of questions of stability because these facilities for observational astronomy are so incredibly expensive nowadays.
Yes, they are really putting in a lot of money: 50 million marks. Of course, 50 million marks for Germany is peanuts. It’s like in this country: $5 million for another 200-inch telescope is nothing.
But it’s the same problem that Hale originally had. He could get Yerkes to build a telescope but not a cent for support. And thats exactly whats happening again. Thats a sorry note. But on a happier note, though, lets look back over the almost 25, 26 years you’ve been here.
Twenty six years.
Twenty six years. What do you think have been your most lasting contributions not only to the observatories. Obviously, your legacy of Ph.D. students to astronomy in general?
Well, I guess I’ve mentioned them already, those that are really pet subjects that I’m proud of: the question of the— not the discovery but the realization— of the importance of the pressure induced absorption is one. And, well, the interstellar absorption that’s purely observational, And the contribution of value the question of the internal motions in emission nebulae.
Struve in his book, Astronomy of the 20th Century, seemed to be quite impressed with your discovery of the two types of clouds and the two types of motion, the smaller clouds with the high Z velocity. How do you see that in your own work as far as understanding what galaxies are, or at least that component of them?
Its very strange, let me put it this way. I never really could relate it to the grand design in the sense that it would be too wild, Intergalactic matter, large scale circulation from the galactic center, all these things too remote.
But we have two different populations, and their kinematics seem to fit somewhat the kinematics of your two classes of clouds.
That’s right: the one ordinary galactic disc normal velocities and then very high velocities way way up, go way way up the galactic plane. And the question is: most of them are caning down—are they part of a, say, piece of gas blown up in the center and just raining back from a supernova? We don’t know.
But they have to be accounted for.
Again that’s something which I would love to get back to now that we have the 21-cm data and really good receivers.
Germany certainly has some marvelous receivers.
I have talked to the people in Bonn about it.
I was just going to mention: they have a 300-m or 300-foot telescope?
No, a 300-foot. Something built like a battleship. With standard but good receivers…a good system. It’s not a system that is in the front line of radio astronomy, but as a working system and it’s very effective.
I understand the difference between the two. It’s a very subtle but very strong difference.
And I’m afraid that if we want to make the observatories in Spain a similar kind of observatory, we’ll never catch up with the observatories in the United States. But hopefully we’ll make them very sturdy and “operator...proof” [laughter]
Will they be run like national observatories as they’re run here pretty much?
It will be a national observatory. But there’s a home institution.
And that’s the Max Planck Institute.
Yes. And we have a certain amount of observing time, and the rest is given away to the visitors.
We’ve covered almost four hours of tape. It’s also about time for you to go to dinner, which I think is the most important point.
Well, I’m afraid it might have been a little bit disconnected, you know. It’s really very hard to put it in order, isn’t it?
There is one final question. Could you amplify a bit on what kept the Mount Wilson observers away from observing spiral structure optically?. You mentioned that you had talked to Adams and what did he say about it?
And he just smiled and said, “Well, that was the only way to build a telescope.” They could have done the work with the 60-inch at Mount Wilson, but the 60-inch never had a Coude there.
So the combination of these two designs kept you from measuring interstellar absorption.
But it could have been done in the mid ‘40s possibly.
Without any question. The stars are a little bit faint and they were marginal, but still the fact remains that in the Adams Catalogue there is one star, AO Cass now thought to have a black-hole companion. Well, anyway that’s in the Perseus arm and is the star which has the most complex lines of all the Adams Catalogue. So it was very clearly written. So I don’t think there’s any question he would have found it, the old boy, in the early ‘40s.
It was just a quirk of fate because he didn’t have the telescope.
Okay, I wanted to get that on the tape. Okay, that’s it.
 Münch Microfilm (AIP)
(It is in microfilm).
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In Münch collection, A.I.P.
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Apj 104(1946) p 87.
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HCO Circular #453 (1949) p 1.
Radiative Transfer, p 266 formula 175.
 (This is not HCO Circular #453 1949 ?? ).
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