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Interview of Bernard Lovell by David Edge on 1971 July 6, Niels Bohr Library & Archives, American Institute of Physics, College Park, MD USA, www.aip.org/history-programs/niels-bohr-library/oral-histories/4749
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Formation of Jodrell Bank Observatory, Patrick M. S. Blackett's support of cosmic ray program; staff members; early strategy at Jodrell Bank, radar meteor work; flare stars; importance of "accidental discoveries;" Hey-Appleton-Ryle; the Cambridge group, past and present; major achievements in radio astronomy; important contributions of Jodrell Bank; Cambridge's major contributions.
Sir Bernard I wonder if we could start with a few questions about the formation of the group here at Jodrell Bank, how the people who came together in the first year or two were brought together. How many of them were people you had known before during the war and you approached to join you and how many came in other ways?
I think in the beginning the answer is that they were people I knew during the war. The position is of course that we were… became an off-shoot of Blackett's department, I don't know if you know that history or if it's relevant to this enquiry, but it is rather important; are you going to need me to say a few words about that?
Well we would like to ask a little later on more about Professor Blackett and his relevance.
Yes, yes… well. I don't think I can give the answer to the first question without telling you how I came to Jodrell Bank in the first instance because after the war I came back as a lecturer in Blackett's department with the intention of using this G.L. radar stuff which I brought back with me to detect cosmic ray showers, there's a paper which Blackett and I had written during the war, and then eventually we found we couldn't work in the quadrangle of the university and then we found this place at Jodrell Bank. Well in the beginning I moved out here with a technician who had been one of my technicians in my wartime group called Young, and he wasn't really fulltime with me, I was practically here alone but occasionally he came out about half a day a week to help me with the stuff, and I had a couple of gardeners here to help me start up the diesel. So, the beginnings were extremely rudimentary like that; and then after about four/five months of a bad winter here, Blackett did say that I could have another man. Then I got people like Banwell and Clegg. Those people had been not in my own group in T. R. E. but had been people I knew in T. R. E. and other groups who were anxious to come back. So I think the answer is that initially they were all my winter collogues, either in my own group or closely associated with it in R.R.E.
Banwell and Clegg you did actually contact, I mean you knew you could take on an extra man, you wrote to them perhaps to contact, or how did you…?
Yes. I think that the position there is that Blackett was anxious to recruit good young people for the Physics Department as a whole. So I suppose I did my share of recruiting young men of my acquaintance who were anxious to get back to university and a lot of them stayed in cosmic rays, but I got onto one or two of them but we were extremely small and rudimentary at the beginning.
Could I just ask you about the people whose names I've got down here as joining Jodrell Dank… Moran… where did he come from?
Moran… no I am afraid I can't… if you'd like to pause I can get hold of the files a moment and try and find out where I'm… I remember Moran well, but I cannot remember at what time he came or whether he was a member of the T.R.E. group, I think not. Do you want me to find out about that?
Well we needn't break now but it’s something to be checked over later because I have him down as joining in '45, apparently the same time as you arrived.
Yes, yes, he was probably one of this group of people… '45 he certainly didn't come out here with me then. I should have thought Moran would have been well into '46, but that I can't be absolutely certain about. I think the only… there was a young man called Forsyth, who was also, who went into law eventually in Glasgow but he was a young man in my group. Could be that Moran was as well, I'm afraid, sorry, I can't remember that.
Banwell and Clegg were at T.R.E.?
Forsyth, was he…?
Forsyth was a young man who was a member of my group and there's another young man called Parker who was a cellist, a very vague sort of individual, he was in the early stages associated with me, and he was a member of my group at T.R.E.
And Hughes… Hughes… I believe so… Hughes, I can't be certain about Hughes, he may have been… I think he was '46 he may have been a student who… one of the students who began to come after the education started up again.
What the first of the new… of the…
Yes, but I… we could check this in the files afterwards because I've got individual files on all of these people.
And how did you… how did Ellyett come from New Zealand? Was he over here at the end of the war and moved here or did he come…?
I think that Ellyett was a person who had some scholarship to come here but I'm sorry… I will have to check all this on the files… you know this is a very long time ago.
Yes, there is one or two that are later, A. Spinall and Gatenby and of course John Davies whom we interviewed yesterday.
But of course a classic example of recovery of brilliant talent is Hanbury Brown.
Yes, how did Hanbury Brown come?
I don't know if you want to… well I can tell you very clear about that because that was a very remarkable episode. Hanbury Brown was a very close friend of mine during the war, he stayed with us for some time and then he went with the British team to America to develop some stuff there and we lost touch with him.
Radar, yes… as a member of the R.R.E. team working at M.I.T. on something. So we lost touch with him towards the last year of the war and heard nothing about him for a bit until I heard that he was, he'd joined up with Watson Watt and Partners, and also with Watson Watt and Partners were Vivian Bowden and a fellow called Trufoot. Well I… one day Freddie Williams, F.C. Williams who… Professor of Electrical Engineering at Manchester, who developed computers, was again a close colleague of mine at T.R.E., he phoned me, this was in May 1949 but I'll give you these dates precisely if you want them, he said, look an old friend of yours Hanbury Brown wants to come back to a university to take a Ph.D. He wants to get out of Watson Watt and Partners, and he's written to me because he's electric engineering and feels that I can help him, but I think he will be more useful to you and so I said well it’s just a gift from heaven, this is exactly the sort of man we want, Hanbury, if he, if this is really serious so I got this correspondence, and I looked it up recently because I have written about this myself, on the early development of Jodrell, and Hanbury duly visited here, and straight away said yes this is the sort of thing he would like to do, join in some… we were then just developing our big 218 ft. parabola, we just had that working about 1948. The only problem was that, to get him a grant. Well he had such a first class record as an engineer but very little academic achievement, this was not too easy in those days, but anyhow Blackett eventually managed to get an ICI fellowship for him. So Hanbury came back here as an ICI Fellow, then, that’s how he came here, there's a lot of other story to the future of it. But this is, I think, a very interesting and very important example in the history of the development of the subject, how Hanbury Brown got into radio astronomy, it was just really the chance contact, not only wartime contact between him and me but also the other contact between F.C. Williams and myself and I've told Freddie Williams quite recently I said, "You know it was really one of the best things you ever did, this generosity in suggesting that I might take Hanbury Brown.”
Could I just ask you a little bit about… because Hanbury Brown we may not be able to interview for obvious reasons.
His background, as I understood it, as I heard of it, he did qualify in engineering just before the war, in an institution…
Yes, City and Guilds.
Yes, City and Guilds, that's right. Which he took, did he not, at Brighton, in the technical college?
That's right, Brighton Technical College, then he was already in the Air Ministry Research Establishment, as it then was, before the war. He was working in the place when I, when war began and I got into it.
And when you recruited him here, or engineered an I.C.I. Fellowship for him here, you weren't thinking of any specific scientific problems for him to tackle, just the fact of getting a chap like Hanbury here, was what was in your mind?
And very rapidly Cyril Hazard joined him.
Well Hazard was one of our own students, who came here with a D.S.I.R. That date would have been a year or so I think, do you have that date…?
I have that date down here somewhere, yes, it is in '49. In fact there's quite a string of people, Sedra, and another Egyptian.
Sedra and Hazzaa, yes, well they were no good.
How did you come to have Egyptians joining you that early on, I mean that seems a rather curious…
Yes, well of course the relations then with Egypt were pretty good and I suppose we were already internationally minded, and it was great fun to get people from all over the world, much more fun than it seems to be now. We've got a few good ones, but we got quite a lot of bad ones. Sedra and Hazzaa were amongst the not-so-good ones — they were quite pleasant people.
And there's Closs from New Zealand, and Greening.
Yes, yes, well Closs from New Zealand, again I shall have to look in the files. I can't remember how he came but I should think this was almost certainly some sort of overseas scholarship. Greening was one of our students who didn't do very much and eventually went to Italy and then I was surprised a few years ago to find him back in S.R.C., space administration there.
Hawkins of course who is now at Harvard.
Hawkins was a young man at Nottingham University who as a student came here to help us observe meteors visually. Our initial contact with him was nothing to do with the war, was through" Manning Prentice and he and Ovenden [???] who is now, who was at Glasgow and has now gone to British Columbia, were part of Manning Prentice's observing team in the B.A.A. and this was part of the Prentice organization when he had his team sitting outside our trailers and we were looking at meteors doing a visible correlation and Hawkins as a student, undergraduate, was in that category and he then wanted to come here and came with presumably a D.S.I.R. studentship.
And has stayed within meteor work?
Well not, no. Hawkins after a bit left — a very ambitious man Hawkins. He went to Harvard and did a lot of meteor stuff there but of course he rapidly moved into other fields. He became, a few years ago, Dean of some university and I had a letter from him a few years ago asking me if I could help him to get back into England again, but I haven't done anything about it. But Hawkins has sort of become a very important man, went into all this business of computing the Stonehenge. So I think that during the last ten years I doubt if Hawkins has done much serious meteor research. I think he's been mostly administration, Dean…
Yes, I’ve traced a number of meteor papers in the Astrophysical Journal but they're probably fading out in the sixties.
Are you tracing the future history of these people as well as…?
We're doing our best, but as you might imagine it's quite difficult…
Well of course my — if you want to find out about Hawkins you had better ask my other son Brian who you know, because he knew Hawkins pretty well and he can give you the, quite a lot of the story. But I think that he, it was said he had resigned from Duke University or something like that, but I think in Brian's opinion it was just made too tough for him, but I don't know that. But what he is doing at this moment I wouldn't know, but I think that he became so successful as a popularizer of science and made such a lot of money out of Stonehenge and things like that, that he probably doesn't do much research now.
Maxwell was another one…
Maxwell again came from New Zealand, I must look, I cannot remember the case of, Maxwell and Closs, whether they came with D.S.I.R.s because they would have been eligible, I imagine, for D.S.I.R. studentships or whether they had overseas fellowships, but… what do you want to know about Maxwell, he was a very, very nice and is a very nice fellow. He worked a lot here and then decided to go to America.
He appears in the Harvard group.
Yes, well, Maxwell is still in Harvard. He set up, he persuaded, he went to Harvard and persuaded them to give him money to build the, I think it was the 60 ft. dish somewhere in Texas and he then set up a group there and attracted another of my very good young men called Thompson, A.R. Thompson, not John Thomson and did some very, very good work on solar physics. And Maxwell, I think, of all these... he's quite different from Hawkins I mean Hawkins has moved into the higher flights of administration and so on, but Maxwell has stayed a scientist, he’s done quite a lot of work. We still see him quite often, a very, very nice fellow. He was an accomplished organist, but I think he gave up. Now A.R. Thompson, at some stage he left Maxwell's group and went to Berkeley, where he is now on radio astronomy doing the spectral line work.
Yes, I think that — I have been in the looking up in the Astrophysical Journal to the end of ‘66 and I don't think Thompson has published from Berkeley up until that point, so I haven't actually picked up …
Well, he will have done since then. He's worked on variability in these OH lines.
Yes good. These people who came from abroad, did you have any hand in picking them; were they nominated by people you know abroad, the New Zealanders for instance, or did they just appear, you had an overseas student…
Probably appeared. I, really I'm sorry but I, my memory is not now good enough to remember exactly how they appeared. But it is important in this conversation for you to remember that Blackett was a very great cosmopolitan. He was a really great internationalist and, I mean if you were, if you were English it was already a bad mark. If you were from overseas or foreign then you were already half- way up the ladder with Blackett. And this set the atmosphere so it was not at all unusual that, of all the mess of foreigners and overseas people who flooded into Blackett's department in the five years after the war that I got quite a few, got quite a few of them.
Das Gupta would be another one I…
Yes Das Gupta would, Das Gupta would be another one.
And the fact that Blackett had this cosmopolitan point of view is one of the reasons why so many people from Jodrell Bank appeal abroad again going back to New Zealand particularly, Ellyett, people going to America and so on.
Yes, I’m… No I'm not sure if it works in the reverse way, I don't think Blackett would have exerted any influence on people going again, not necessarily. I mean, I think he would have been quite entirely open-minded about that, would have been glad for them to have stayed or to go back to where they were. I think that in the case of Maxwell and Ellyett, certainly, who were both very, very good people; of both of them I was very fond, I think in those cases I would have been only too delighted to have kept them but it was their own desire to return. Ellyett, I think as far as I remember, came over specifically to take a Ph.D. and then go back to New Zealand, but of course he eventually, after a bit went to Australia.
But he built up a team doing meteor radar work before, he went to Australia.
In New Zealand... And again Maxwell, I think I was very sad indeed when Maxwell left, but nevertheless, so this was not pushing out… Now Closs on the other hand is a different matter, because he was not, he was a nice individual, but he was not very good, and the paper, the absolutely first-class paper of Kaiser and Closs on the meteor theory is very largely Kaiser, however …
Yes, did Ellyett come over in effect to do a Ph.D. in meteor radar astronomy, was it the kind of thing that would have been that clear, that early.
I shall have to look in the, I shall have to look in the file I'm sure this is clear in the files, but all those people from overseas they do come into this category of, having been recruited by Blackett… you see I wouldn't have had, at that stage, I really was only a lecturer and really did only have trailers in the field with a secretary who came in occasionally and worked in a trailer. So I wouldn't have been a recruiting force, not in the sense that we are now. I would have been an entirely junior person in Blackett's department; he would have been feeding people out to me.
Could I ask something about just two people in particular that were… apart from Das Gupta there's Jennison and Kaiser and Murray, in 1950. Jennison and Kaiser of course were… have stayed very much in the business.
Jennison yes, well now Jennison and Murray, could we take those two together, because they were exactly parallel? They were both service people during the war. Now I didn’t know them during the war. Murray was son of Admiral Murray actually, the Canadian admiral, he was a lieutenant in the navy in the arctic, on the Russian convoys as a matter of fact, and Jennison was a navigator in the R.A.F. And they returned in the post-war group to take degrees that… I remember lecturing to them, they were in my class.
Yes, as undergraduates, after the war. And as students both Jennison and Murray were obviously very good and were desperately keen to come here and help. I think for two long summer vacation during their undergraduate course they came here and worked, help us build telescopes, with what we were doing. And then, of course so you see the natural sequence, we were only too happy to be able to get D.S.I.R. grants for them. So I'm perfectly clear about those two.
Were they the first two who came as it were knowing precisely what was going on, having been prepared?
I should think… yes, I think they probably were… I'm a bit uncertain about Hazard. I think he was… he was later was he. Hazard was also a student in one of my classes who like Jennison [???]
No, no he was in fact a year earlier, a year before. [???]
He was a year before, I can't…
Yes, we have interviewed, we've had an interview with Cyril Hazard.
But Jennison and Murray, I'm quite clear about those two, I mean they were old enough to have served in the war and yet young enough.to come back and take degrees afterwards, and they were in the category of students I lectured to and came here, and did a lot of useful work for us in the vacations.
Where did Murray go to?
Murray, he went to… he did a lot of the moon work here and eventually left to go to R.R.E., where he still remains, I think.
Oh, he's still there is he?
I believe so, yes, he was a year or so ago.
But not, I think, publishing in radio astronomy.
Oh no. Murray is tied up in very… in secret work.
Oh, I see.
But he has been dealing in fact with radar… Look I don't really know what he's doing now, but he was largely responsible for setting up the R.R.E. system for the radar investigation of carrier rockets and sputniks, and this followed on directly from his work here where he was doing radar work on the moon.
Now Tom Kaiser.
Now Kaiser of course, the most brilliant of the whole lot. He … and the most difficult. He came, I think, as an I.C.I. Fellow handed on by Blackett; I can't, I shall have to look in the files to see where he came from, but he was an Australian I think. But I mean difficult because in those days he was a very… very ardent communist… and… well this is not the subject of the interview.
But these things do… well but these things do make a different in the group, of course.
Well yes, I mean in the history of what happened here, which one day when I retire I might write, the impact of Kaiser in conflict with Murray, who was an establishment man was really or of the most extraordinary episodes in our whole history, but this not for this… but Kaiser was a very brilliant individual and he had a very great impact on us. But, I will look up, I mean — sorry but you are — you must remember that I’m now reaching the age where one’s memory tends to be not exact, because I’m not telling you things unless I’m sure about them, but I do have these in the files.
It would be extremely useful…
We will look at the files on these individuals.
And if it were possible to have one or two copies of key letters and things of this kind it would be very useful. There are one or two others in the following list. Stan Evans.
Stan Evans was again one of my students; well what do you want to know about him?
He came as one of your students?
He came as one of my students, D.S.I.R. grant and he, we then sent him as part of the Halley Bay expedition. You know all about that do you? And then after that he wanted to leave, he never settled down again and took a job at… became director or assistant director of the Scott ... Polar Research Initiative in Cambridge.
He’s just taken a post as lecturer in the Engineering Department at Cambridge, he's just moving, he wrote a week ago to tell us so.
Well, I had a letter from him three weeks ago, he is on the [???] board; he was trying to recruit somebody for this Scott…
Yes, I noticed that letter on the board.
Well, he is a very nice fellow. We liked him very much and of course we were intimately associated with him with the epic of the Sputnik. But he never really settled down, that’s a rather interesting feature I find that these people who go away, it's a grievous error to attempt to attract them back again, unless they really do want to come voluntarily, and perhaps I over-persuaded Evans, but he was always slightly restless after Halley Bay.
Yes, I think that following on from that, the later years, it's fairly clear how people come to be recruited here, I mean by the time that people are beginning to know what Jodrell Bank is doing. So you get Henry Palmer coming from Oxford knowing what kind of work's going on, and also you have more students coming through Manchester. Do you want to ask, Mike, about Blackett; a bit more about his role?
Well we're beginning to develop a picture of Blackett's importance for the formation of the group.
Yes, well, of course this was of very, very, high significance because I think that anybody with less foresight than Blackett, we should never have emerged.
He was quite receptive to the change in emphasis which occurred quite early on from cosmic rays to meteors?
Very much so, tremendously enthusiastic about it. You see this was really a very great piece of good fortune. As you, as one looks at the historical perspective of it Blackett was always interested in many things and particularly interested in astrophysics, cosmology and… partly, naturally, I suppose because he was interested in the possible origin of cosmic rays. But he never, I mean we had our clashes as you can well imagine, but in the broad canvas he was a very, very critical factor in the whole affair. After all he allowed this place to grow, twenty, twenty odd miles from his main department and gave me money — small hundreds of pounds to begin with and then we were off onto a separate budget, and the manpower all of whom he might well have said he wanted for his own cosmic ray research. Whether… it is of course an interesting fact as to whether — if Blackett would have had that attitude if it hadn't been — if the original incentive had not been in cosmic rays. I think the answer is yes, he would have. I think he was so fascinated by the whole of this, by the techniques, and by the subject matter. If I now think of my own attitude to one of my own individuals doing that sort of thing I mean I would like to think that I would behave as Blackett behaved. I'm damn sure that I wouldn't.
Did he follow the actual content of the research?
In detail, and he used to come out, I mean he came on that famous occasion of the great Giacobinid shower in 1946. I mean he was, he came out with us and observed at 2 or 3 o'clock in the morning.
Did he scrutinize the papers you wrote out of that, the early papers in the Monthly Notices; did they go through him?
For a bit, and then one day he said look there's no need for you to show me your papers, you've come of age.
You can't date that can you?
Pretty soon after the war I think. Yes, I think before the series of 1946 papers or during…
Well I think after, I think during, possibly during the early stages. No, he was the sort of man who once he'd made up his mind I think he was, had sufficient faith, there you are. But I mean I don't know what else you want to know about this, all that I can say is that this place could never have happened I think with many other professors in Blackett's place there.
Yes, I was interested in I think in one of our interviews yesterday when it was suggested that he also attempted to establish relationships between the radio astronomy group and the astronomers at Manchester, even to the extent of trying to form a special group of astrophysics.
Theoretical Astronomy Group. It was suggested that Blackett arranged for Kopal to start that group as a back-up for your work here, as a complement to it.
Yes, I think that… This was all part of Blackett's wide-ranging interests. You see when Blackett came to Manchester there was only one professor, the Langworthy Professor of Physics. Well professors are now two a penny, in those days a professor was a very rare animal. And, within a very short time he had got Hartree over as Professor of Theoretical Physics and then Hartree decided to change his emphasis to Theoretical [???] physics and Manchester created another post for Hartree. Blackett then got L. Rosenfeld in as Professor of Theoretical Physics. Then he persuaded the vice chancellor of the university to create a post of Professor of Astronomy and I mean I was not a, I don't know what I was then, a senior lecturer or reader or something like that and Blackett got me made to a special chair after this appointment. Nevertheless, I was very closely associated with the interviews of these people for the professorship of astronomy and we had three people in the short list, Kourganov (Paris), Ledoux, and Kopal. Well, as a matter of fact our choice was, fell on Ledoux from Belgium. But he wrote very nicely and said he’d thought about it and decided not to come and we, so then we felt that, Kopal with his very, very great knowledge of the skies and so on would not only be very good for the department but also be very helpful to us. So that’s the history of that.
But the first choice, Ledoux was not really one made in relation to you?
Not at all, no it wasn't, Ledoux as you know is, you know, Ledoux was a mathematical astrophysicist, so I’m not sure, I think the remark, whoever made it yesterday, may have been a little hind-sight in this respect, the true history is as I have stated now. I well remember Blackett being rather disappointed about Ledoux… I am quite clear about this bit of history. The suggestion of some other interviewee on p.14 that Blackett did this is [???] Well, he did feel about Kopal that he would be also extremely useful to us as indeed he certainly was. And look that was, has been a pretty thorny passage I think, not between us and the Department of Astronomy because our relations are very, very good and very helpful, but within the Physics Department… I mean that things — that have not been too smooth with Kopal. But it was a very, very good thing to have done and they both Kopal and his team of course have been a tremendous help to us and our relations are close, but I think that there’s slight hindsight in the suggestion that the choice was made that way; it happened in the way I described it — really.
How did you first come across Kahn, who was I imagine the key person in fact really as a contact in the Kopal group?
Well I had nothing to do really with the appointment of Kahn. I in fact rather have the impression; I'm not sure about this, that he came as first of all in the Mathematics Department.
That is correct; he did, yes.
Yes, I'm sure that Blackett did though because I remember Blackett, I said well Kahn, but he's an expert on inter-stellar Media. He said oh yes, of course, of course, good people; we get good people, something like that anyhow. I had nothing to do with his appointment.
But you did know of him before?
I knew of him certainly.
You'd met him and talked…
I don't know whether I met him, I don't remember meeting him, I may have met him at a conference, but I knew his papers because he was writing on things which were of great interest to us.
And he has maintained, we've heard from other interviews, very close contacts with the group throughout.
Oh, yes. Kahn… Kopal is a difficult contact because he's away so much, but Kahn is our contact. I mean if I, and I think this goes for most of the other people, we go straight to Kahn. The last paper I published on flare stars, the man I went to was Kahn and in fact he wrote a separate opinion paper as well. And this goes certainly, goes for all the other people here.
One thing about the Jodrell Bank group that stands out in relation in particular to the Cambridge group and that is that Jodrell Bank never had a resident theoretician. Well, there have been theoreticians in the Jodrell Bank group, Ireland and Reddish, but in Cambridge they've had Harriet Tumner, Harry van der Laan, and Longair, who I suppose was the previous theoretician, and now Peter Scheuer is resident theoretician. Is your close relationship with the Kopal, and particularly with Kahn, group one of the reasons why you haven't pressed this?
Well, it's an interesting point. I don't know really but I suspect that there are two key factors here. One is that because we do have an absolutely first-class theoretical group in our department. I mean we are all in the Physics Department, and therefore there is this feeling which I have as the subject’s got more and more difficult and more and more specialized that it is a slight absurdity to try and set up a separate specialist theoretical group here. I mean even if I wanted to I would have great difficulty in getting away with it because the natural place for those people is in Kopal's department. But the other Specific difference from Cambridge I think is that although Martin Ryle works at Lord's Bridge they are much more based I think in the University building than we are here and I think Ireland and Reddish both felt rather isolated in not having any sparring partners here. I think it's as simple as that.
How did the idea occur that Ireland and Reddish should come here? Whose idea was it and how was it arranged?
I can't remember, possibly mine, possibly one of my endless ideas which haven't gone forward. There was a time when one's energies weren't completely absorbed as they are now in things of the present or things of the future in the observational sense in which one was still branching out and being empire-building and expansionist. I think just that and I would be prepared to justify this. I don't regret this at all. I think it would be difficult. I don't think I could possibly have got away with this with the university in trying to build up a separate group here.
But both Ireland and Reddish are very good people; Ireland going off to work with Hoyle. Reddish is I think in many ways quite outstanding. So it wasn’t by any fault of their theoretical ability that they fell away.
No, no. I think the fault was ours, it was a bad move. They had no sparring partners, there was no possibility and it could not have made sense for me to have built up a theoretical team here, within these walls. You see the difference… the situation here is that the situation quickly developed where, with our rather scarce manpower, I use manpower in the scientific sense, it became of critical importance to bring every ounce of weight to bear on the major observing facilities and it simply does not, would not make sense for me to use precious staff posts and so on for theorists. That is Kahn's job or Kopal's job.
And you don't have the Cambridge equivalent, an equivalent of the Cambridge Fellowship of colleges to fill up with people who can then be theoreticians lying around which is one thing that Cambridge, at least in recent years, has benefitted very greatly from. Could I go back to the technique? When you first came here, the impression one gets from your writings of the early years, the early year or two, is very much that you came with a technique, the cosmic ray being the scientific hope which was quickly then taken over by meteors, but that your early work here was all exploitation of a technique, and the meteor astronomy became the obvious astronomical problem to tackle with that technique. Would you yourself say that it’s fair to say that the technique was the determining factor in the early strategy of Jodrell Bank rather than the astronomy?
I've never thought of that, I suppose you could twist it to say that. I didn't think that… I don't really know how to answer that question. After all, I had no money, I borrowed what would have been fabulously expensive equipment, I brought it back with a lot of other stuff from the Air Ministry or the Army, and the reason for doing this and the reason that Blackett allowed me to do it is because there were a lot of phenomena that we had observed on the cathode ray tubes during the war which on the basis of the calculations we'd made could reasonably have been attributed to cosmic ray ionization. But in fact, when these were investigated… turned out to be almost wholly associated with meteors. And I don't think it was a worship of the technique because there was very, very little technical development of that apparatus during the first few years, we just used what; we just use it. But I mean the only major technical development was the business of triggering the time base so that one could get the Fresnel zones and observe the velocity of the meteors which turned out to be …and it was some years later before when J. G. Davies developed and got the three station technique for the observation of individual meteor orbits. But there was nothing like the subsequent intense development of techniques which have grown not only in that field after we'd more or less abandoned it, but elsewhere. No, I don't think it was; what's your phrase: Exploitation of technique. No· Exploitation in the sense of technical development. It was simply using the rather, what was beginning to be by 1948 or thereabout, quite crude by electronics standards simply using that technique to observe the astronomy. No I think the astronomy was the fascinating thing. It was not only meteors of course, but then we got the solar emissions and also the aurora, and those are the exciting things, not the transmitter and stuff was just the thing which one turned on.
Yes, but it was what you saw, your account of how you started seeing auroral echoes, this was what you happened to see with the technique and then you take an interest in it. And you came here with your apparatus but knowing nothing about meteors. It wasn't that you came with astronomical problems to solve.
The only scientific problem I came with was the one of cosmic rays.
Which was quickly shown, with the technique at the time, not to be… Now you developed here…
There's another thing. Coming back to this point about Blackett, you see, this was the remarkable thing about Blackett when he saw that we were really going off shooting off on a sideline which had nothing to do with cosmic rays, he would have been entirely justified and might under other circumstances, historically, been severely criticized for not putting a damper on it. What I ought to have said in that respect is that he not only encouraged me but had to fight my battles with the university administration, because in those days the university was a very conservative institution. They were not taking kindly to the idea of a young man bringing out trailers and setting them up in what they thought was the botany department you see.
The whole of the radar meteor work which you published, the first papers issued, in fact continued to publish, there were quite a number of papers, in the early 60’s. Do you look back on that as being a sequence in which a number of scientific problems were posed and solved, in a sense disposed of? Do you see yourself as having promoted the idea of radar meteor work so that other people in other places took it up so that a new subject in a sense developed? Or is it a phase, a scientific phase which you think has now — has almost played itself out?
It’s always difficult to say that thing has played itself out. I’d have thought that we'd had solved a major astronomical problem about the meteors. They're solar, not an external thing, entirely part of the solar system. And, we had opened up, and I wouldn't say more than opened up the physical problems because the physical problems are still not completely solved, I mean they are very closely integrated with the physical problems of the whole of the ionosphere and atmosphere. I mean just that. But 1 don't know what else there is to say about it, I was even more conscious of opening up the subject of the radio studies of the aurora, and a subject which I think grew on a world-wide scale after the International Geophysical Year particularly in an even more lavish way than the investigation of meteors by radio techniques.
Yes, now I've been looking at the astronomical journals and not the Journal of Atmospheric and Terrestrial Physics in which I imagine the auroral material is largely carried. So I’ve not been able to estimate the way in which it's developed round the world. But the radar work on meteors, Elyett goes back to the southern hemisphere and does some stuff there, and there is this independent group under McKinley at Ottawa, but apart from that one gets an impression that, well, there is other radar work on solar work a little bit…
But there's a major development under Whipple at Harvard on meteors… with Hawkins, yes. I mean, in fact I think it could be said that Whipple having been, what shall we say, favorably impressed with what was going on here became, since he was one of the great experts on meteor phenomena, that he became determined to set up a big thing at Harvard, and to a certain extent it could be said that his success in doing that and really employing what was technically possible to do it I mean putting the results on punched tape he produced such a vast mass of data that the rest of the world more or less became amateurs at it. I mean we eventually lost interest in meteors, for two reasons; first of all the reason I've just said, that we began to achieve other major instruments into which it was necessary to put all our manpower, but nevertheless it didn’t happen entirely from my personal desire because at that time I was still in the phase of expansionism and anxious to keep everything going and it was with some reluctance that I saw the final stages in meteor studies, and I rather remember J. G. Davies who was the last man working on it with Turski, a Pole, a man who had been in Moscow. He, I think, I mean J.G. Davies was very difficult to get to publish work anyhow because he's so good at the techniques but my guess is that in the final analysis it was the… when he visited Harvard and saw this tremendous amount of data which Hawkins and Whipple were collecting, which made him realize that there was no future in struggling on here at all.
That one group had overtaken the whole field?
Yes, but the point is that they had not; they were too late because the major results had been achieved. You see, I'm not aware that the Whipple Harvard, the Whipple-Hawkins group at Harvard did make any new classical discoveries in meteor astronomy. They published very little, but they've got incredible amounts of data.
Well this doesn't come out in the journals.
No, well there's a certain office in Harvard that's absolutely packed with this. No this is what… I think that the major Astronomical problem was this of the external meteors. [???]
That was solved decisively.
So that in a sense the scientific steam had gone out of it.
The scientific steam had gone out. It then became a solar system problem of the origin of the relation of the meteors and the discovery of the daytime meteor streams and so on, and there are number of interest… a vast number of problems in this which may have to be solved and one of the problems which we left was J.G. Davies's discovery of the peculiar concentrations of short period meteors… Nobody yet knows the answer to that but after all it’s only one of many other problems which have to be answered.
Yes, you had other problems in other areas coming up.
Yes, the point is that at that stage as this was about the last paper which J.G. Davies published when I myself was already being diverted to the problems of this telescope, this was the distribution of the short period orbits of meteors, and the peculiar concentration around the ecliptic. At that time the mass of data which could have led to a solution of that problem was already being accumulated at Harvard. Why they haven't gone on with it I don't know. I mean I suspect that Whipple himself begun to get diverted to other things, notably the space problems.
But Tom Kaiser has managed to keep interest going in Sheffield, publishes papers up to the end of '66 and probably beyond, I don’t know, I've not looked beyond.
Yes, yes, that is true.
Largely theoretical papers but…
Well, they are based on experimental data, and they are now working on relating long wavelengths, but I think to a certain extent the same thing happened to Kaiser though I wouldn't know, I have never asked him this question. But he became, developed an interest in experiments in space, which he's done very well.
When did you first become aware of McKinley's group at Ottawa?
I can’t answer that, I. imagine almost certainly at one of the U.R.S.I. conferences, I should think; what U.R.S.I. conference that was I can't remember. I should think it was possibly Zurich 1950 or whenever that was 1951 something like that.
But shortly after that the first of their papers …
Yes, and Millman actually who was — I don't remember having known McKinley, but Millman I did know during the war; he was in the Canadian Air Force. Millman was the astronomer. Peter Millman.
Did you have a close relationship with Ottawa or was it simply the reading of papers and…
Not as close as with Harvard. Close relationships, close astronomical relationships in those days were with Fred Whipple, and in England with Prentice and Porter who was then at the R.G.O.
And the close relationship with Whipple was cemented by the meteor physics symposium here in 1952, but it was existed before then.
Yes, yes, I think that presumably that meteor physics symposium — when was that ’48, '49, that would be the first time we had international people here as visitors and including Russians, well Russians, Russians and Czechs you see have also done a lot of meteor research.
Now you yourself got involved in the scientific problems of meteors. Do you feel yourself some regret that the actual science you would have liked to have gone on a bit, you mentioned you'd like the work to have gone on a bit further. Would you yourself like to have been involved further in it?
No, my own attitude is very simple. I lose interest in a science when it becomes popular. I mean I'm just interested in new things. I don't know why this is, I mean it's a grievous fault maybe. Perhaps laziness, when papers begin to flood out on subjects from all over the world I just lose interest and start on something new. Look, it's with no sense of pride I say that it is just my nature.
You have a situation where the major meteor problems you say are solved, the origin, all to your satisfaction. You have Hanbury Brown around and Hazard and Walsh and others and source problems are coming along. You divert your attention to that, your scientific interest to that. Now the flares star one, when did you start getting interested in the search for flare stars?
Yes. I can give you the answer to that precisely the, in fact I did describe that in the… I gave the presidential address to the R.A.S. in February on this subject and I think that in the introduction to that I have described this sort of accidental business, which I think is going to be the sort of thing that you may be looking for because it’s just a question of whether you can, as a result of the studies you are making, you can really decide how to plan science; well on my experience you simply can't. I use the flare stars as an indication that indicates and in fact the whole of this of course for we started out on cosmic rays.
This would be coming out in Observatory or Quarterly Journal because both of these I'll get of course.
Quarterly Journal. Look, the answer broadly speaking is this, that in 1957 when we were at last getting over the troubles of this telescope which pretty well knocked me out of any intelligent research for years, as you know I was nearly put in prison because of the troubles here. It was just a part of the strategy for this telescope. Well there were vast numbers of problems which were just crying out to be tackled. I mean the interferometer work and the surveys and all that sort of thing. But they were all obvious and would go on anyhow. But I thought with an instrument, with a new instrument of this power, it would be nice to spend a little of the time trying to do something that hadn't been done before, something new, not go on measuring angular diameters and so on. And so while I was searching round for those sorts of ideas as I've said are rather easy to have but rather difficult to put into practice and you can waste an awful lot of time and money just floating around rather vaguely. But my ideas on that subject were canalized by the fact that I attended the Symposium on Radio Astronomy in Paris in August of 1957, I think, or was it ‘58…
It was ‘58. It was preparatory to Berkeley wasn't it, the big I.A.U.?
It was prior to Moscow, because I more or less went straight to Moscow, I. U. at Moscow. Well at this Paris Symposium Schatzman gave a short paper which you will find in, printed in that book, on the possibility of detection of radio emission from flare stars and well I immediately thought well here is an ideal problem. I mean nobody's detected radio emission from ordinary stars the typical case you have an eruption once in say twenty four hours of a few magnitudes, you want a big telescope which will follow it round the sky. So that's how I started off. Well Schatzman's calculations turned out to be, well you'd better read all about this in the papers because I pointed out that Schatzman’s calculations were wrong and it was really an idiotic thing to start on. But in fact it turned out to be successful because the energies involved in flare stars were many orders of magnitude, turned out to be many orders of magnitude greater than those in the sun. And then after two years with the telescope only on that and getting results which were probably related to flare stars but nobody would believe, I mean Hanbury Brown said you can’t publish this; nobody will believe you. He said you must get a visual correlation. And then the attempt to do this with Dewhirst in Cambridge which didn't come to much because of the sky conditions and then the very good contact with Whipple at which he agreed to put all this, all the satellite tracking cameras. So, well, incidental and accidental contact of life.
And also once again the technique. You happened to have the instrument of particular characteristics and you happened to see the match.
Yes, well this was but, you see this was a more or less international, it was a planned characteristic, it would have been something else other than…
Was it also perhaps the fact that observations could go on in the interstices of other people's programs in a way it would fit in with your own life-style which had become a…
Yes, well, then you come back to the whole problem of the strategy when you’ve grown up in a place like this and have a responsibility for students and — you've got your hands on many, many millions of pounds of public money and then you've got the responsibility for it; the whole problem of the strategy of how you run a place like this. Well, there are a lot of things I could say about that, I don't know if you're interested. I mean the clash is of course between the responsibility to make sure the students you've got you get their published work, which means that you've got to do some sort of bread and butter stuff out of which if you're good a lot of new things do come. But if you just settle down, let that go on for one hundred percent of the time, then you pretty well, the establishment has a very great danger of dying. It's very important always to make people realize that there are things like pulsars to be discovered. Have you experienced this intense conservatism?
Oh, yes, and what's more within scientific establishments. As you say, it's the necessity you know to get in three years something which would be accepted by an external examiner.
I have two battles to fight here. One is the battle against people spending all their time developing techniques, never doing any astronomy and the other is those who do astronomy, just following on along a well-worn line, just churning out the papers.
And you see the flare stars episode as being one sally in a new direction.
It was one sally in a new direction which…
Will be, I mean when we get bigger telescopes too, it's still such a marginal phenomenon that, but already we're finding out I mean now there's been a tremendous stimulus to the visual observing of flare stars quite a lot of new information is corning out about the early history of these M type dwarfs. But in the radio sense one needs even better instrumentation and more powerful telescopes.
Then did you first meet Hey, during the war?
Hey was running the Army Operational Research Group. I think he was the civilian in charge of the Army Operational Research Group at Byfleet. Hey was very good and it was his, one of his G. L. equipment’s — 4 metre radar which I actually brought here or brought to Manchester in the first instance, and Hey and Phillips, Major Phillips, I think it was Major Phillips. Major Parsons too, they actually arranged for a group of army people to do the towing for me.
So you did have contact with Hey and talk astronomy with him, you knew …
Yes, I'm not quite sure when I first knew of Hey’s report on solar outburst of 1942, because that had been published as a secret document. Well, I didn't really have much contact with the army problems of research because I was concerned with the R.A.F. and cannot remember the particular incident which led me to go to Byfleet, but I think it was towards the last year or so of the war when we were concerned with the problem about movement of tanks on the ground which we had a good enough radar to detect. It was probably that, that took me to Byfleet.
So your contact with Hey then was a purely technical matter?
Yes, oh purely a wartime problem, yes.
And at what point did you have contact with Hey on astronomical problems in your new profession?
Well, I think immediately after the war, because of course Appleton was, began to take over Hey so to speak in the scientific sense, they published these papers together and I do remember we, Appleton had discovered by means which I cannot now recall, that we were about to publish in Nature in 1946 our observations of the relation between the big solar outburst of July that year and the radio emission which we'd observed here and he phoned me in a state of great agitation saying he hoped I realized that but for the delays in publication consequent on the end of the war that he Hey had written a paper on this relationship which should have should have been out in Phil. Mag. So I, that was one sort of sharp contact but there was no real competition, I mean I was very friendly with him and he was a colossal help to us, let us have this equipment in the early years. I mean a lot of the other equipment I brought back was my own gear from Air Ministry. I knew D.C.A.S. very well and he arranged for me to have a vast amount of stuff. But the actual gear that we did these initial meteor observations on, on 4 metres, was some equipment which Hey had freed for me.
When was your first contact with Appleton?
Oh, the first contact with Appleton was during the war when he was secretary of the D.S.I.R. and he came to see what a young man called Lovell had; he'd heard a young man called Lovell had a new A.I. device which would lock-follow and I had it on in a hut in a field looking over to Swanage Bay. That was my first contact with Appleton.
And was that a contact that was continued up to his death?
Yes, Appleton was always very, very nice to me. Incidentally, Clark has, I wrote a preface to Clark's book on Appleton which I, for some reason, doesn’t seem to have been published yet.
No, that's true, it isn't out yet. Of course we in Edinburgh are particularly interested in Appleton.
Appleton, we always got on very well together, he was always very, very nice to me.
Although, in fact only occasionally did you professionally, I mean you mentioned the one example here of the possible simultaneous publication, but you were rarely actually researching or working or writing in the same field…
Not really, except of course there was this fringe contact because he was concerned with the ionosphere and we were dealing with phenomena in the ionosphere and another situation arose over the aurora where he got a bit mouthy about that. He said don't you know we observed this during the international polar year of 1932. But he was such an elevated man and I was such a student, but the relations, I always felt that Appleton was very, very kind to me. This is very odd because of course Blackett, I think, he and Blackett had little time for one another or Blackett didn’t have much time for him. However, I was below that, I was young enough to admire and respect all these people.
When did you first meet Martin Ryle?
Oh, during the war. Martin Ryle worked in; well I don't recall knowing him before we were in Malvern 1942, '43.When did he join up, do you know…
Oh, immediately on the outbreak of war.
Yes, well I was, he probably went straight into the main establishment but I was in Bongale [???] airborne group and went straight to Dundee, and then to St.Athan and then to Swanage and maybe I knew him at [???] but the first time that I would be certain of meeting him was, he was in Cockburn's group at R.R.E. and I was…
Now your contact I imagine during the war was purely technical about echoes, radar and so on, there was no discussion then about future plans or astronomy.
No, my contacts then in that connection would have been more with Ratcliffe, not with Martin Ryle because oddly enough I think I’m a few years older than Martin. But so I knew at some stage during the war or remember Jack Ratcliffe telling me what he was going to do afterwards and he was going back and applying these new scientific devices to their …
And did he tell you that he was planning to get a group together and he was going to write to a few people and hoped that they would join him at the Cavendish?
I can't remember that. But incidentally the relations between me and Martin Ryle, I think it's been one of the important situations in British astronomy. I say this with great humility, but in fact you see Martin and I have always been very good friends and there's been a friendly competition between our groups, .but the fact that we have never — always agreed and never quarreled has I think been decisive. And I well remember in lecturing in the Institute of Astrophysics in Paris in '49 or '50 something like that, to people like Kourgtanov they said we can't understand. Do you mean to say that you have actually carried out a collaborative experiment with people in Cambridge? I mean they couldn’t understand the possibility of collaboration. We did this together. And this has continued all along, I mean the agreement which Martin and I have always had to… how we present our stuff and… there has been a recent very good example of that. I don't know whether you want to know about that but about a few years ago when Martin wanted 2-1/2 or 3 pounds million for his new aperture synthesis thing, the three-mile, the one that’s now, the telescope that's just coming into use. And we'd been arguing about building our Mark 5 telescope. And Brian Flowers called me into his office and said look here, do you want me to toss a coin, the budget's been cut. I said no not at all. I said Martin is ready, his is cheap, get on with it and hold ours over. But we will postpone our Mark 5 for two years, because it’s in the forward book, on the condition that we have priority to spend half a million pounds on converting our Mark I instrument. Well, this you see has turned out and will turn out I think if all goes well, historically to have been a very important friendly collaboration, which won't get in history books, which nevertheless has been the kind of collaboration which if Martin and I had not been good friends and if we’d been really competitive in an unpleasant sense, could well have caused a considerable amount of wreckage.
So you have already used the phrase competitive of the relationship between the groups, but this is of course the sort of competition you think is healthy.
Oh yes, very much so. Yes, yes and also it's a certain positive action. I have young people here who say oh well the obvious way to do this is to have aperture synthesis. I say look here, if you want to do aperture synthesis you go and do it at Cambridge. But you easily see how this could go the other way round. Well it's no effort on my part, it just comes naturally, but this is, possibly something you might be interested in.
So as you're looking from Jodrell Bank to Cambridge you see that group as characterized by a technique by the exploitation of aperture synthesis and interferometric… for major surveys as the major field?
And fortunately, I mean it's been a bit of good fortune about this. I mean I think that fortunately the developments, the techniques on both sides have made it clearer and clearer that they are not competitive but they're closely associated in the same subject, but each to its own, each performing important functions. Of course we do aperture synthesis with two telescopes here, even in our interferometric programs we're measuring angular diameters now with trans-Atlantic baselines to a 1/1000 second of arc but we do not attempt to build up detailed maps of much less accuracy, — the sort of thing which aperture synthesis will be able to do [???] seconds of arc. So I think there's been a certain amount of good fortune. I think if Martin and I had been, well I suppose we are to a certain extent fiery characters, but if we’d been really competitive in an unpleasant sense there could have been a good deal of wreckage about. And I do not think that either of us would have got the money. Yes, you know well enough that if you're going to spend, as we’ve been spending, at any rate of a million pounds a year or whatever it is over the last fifteen or twenty years on radio astronomy, then the slightest breath of discontent or disagreement amongst the experts, it’s just disaster.
Yes, there are two aspects of your contact with the Cambridge group, one is as you say the political one, which is, the various committees that have met and you mentioned the… Ryle in Appleton's room in Edinburgh, the meeting over the telescope way back in '53 or thereabouts would be, I imagine, the first major group in which you and Ryle and others were engaged in political decision. That's continued amicably and always looking back on it you think just decisions have been made, there have been no untoward…
None at all, that would be my judgment, I don't know, I've never asked Martin what he feels about it, but you probably have, but I hope that he would feel the same thing.
Yes, well I think that they would agree I mean Martin always has got what he wanted and at first his budgets were somewhat more modest as you know, but now he's in the big league too, so he knows what it's like but the other thing …
I don't really know — he’s spent more money than we have. I mean we're always rather expensive boys but in fact I think…
He’s proliferated, yes. Well by the time I left, that was the end of ‘59…
Well it could be said also that I always got what I wanted, I'm not sure, I might have done but it's a very critical point at issue here. I mean if the Mark 5 or the Mark 5A comes about then the answer will be yes I have, all the cards have fallen well, the last critical move being the one I described when I said to Brian Flowers we’ll do this and let Martin get over the hump there. Those cards will fall into place if the Mark 5 is built, but if the Mark 5 isn't built well I shan't be smiling to myself because I shall say oh we shouldn't have wasted ten years on the Mark 5. I should have seen the red light earlier and gone and done something else, doing a Mark 2A or something like that, but I don't know yet, it's one of the gamble one takes. But I'm quite sure that the decision in 1967 about three, or four years ago, that critical decision which I got through in State House about letting Martin do that and giving us a minor amount of money to modify and renovate this was absolutely correct. There's no doubt at all about that. [???]
And Martin was very cooperative in that decision then?
Oh well, yes, I mean he agreed because after all he was giving up nothing. [???]
But the other aspect is the scientific one. I mean one of the most important features of development of radio astronomy not only in this country but in the world is the, what happened in the history of the Cambridge survey work, as you know the 2C survey was, I think the word would be, over-confident, and following on that and the claims, the cosmological claims made there was the statistical analysis that Scheuer particularly had a hand in, the P of D. These two things together and the reaction to them made the Cambridge group extremely defensive. And indeed there were people in Jodrell Bank, as you know Hanbury Brown and Hazard who both had serious misgivings about this statistical technique, P of D, and indeed not only that but Bondi and Gold and a whole string of other people refused to take it seriously. And for many years the Cambridge group have been on the defensive, I mean people describe them as cagey, and holding their cards close to their chest. Do you, looking back on this, feel any sense of resentment of the behavior of Cambridge or…
Not at all, I would agree that they're cagey; but I don't feel any resentment.
You think this is understandable, their behavior?
I admire them for their science… well I yes, no I have a very great admiration for them. They are cagey. I know the criticisms. They are criticisms which I share myself. But, nevertheless, the whole of the Hoyle, Bondi, Gold stuff, steady-state and so on may be a lot of bunkum, but it’s been an enormously important feature in the development of cosmology. I mean the present conclusions of the recent Cambridge surveys, I would still regard as being very important, but not necessarily decisive. But nevertheless, I think they are of vast importance and the stimulus that both they on the one hand and the theoreticians on the other [???] have been tremendous, made the subject live during the last fifteen or twenty years. On the subject of caginess, I think that they have, I don’t know whether this ought to go on record about talking about my colleagues who are in Cambridge, but they have perhaps been almost on the borderline of being diffident sometimes, but I don't think they've overstepped the mark. The only case in which I thought I was going to have reservations was the discovery of the pulsars, but I was amazed, I mean I heard about this from Fred Hoyle at a meeting in… a SRE (?) council meeting in London and I simply wouldn’t believe him, but on the way back I thought well surely Graham Smith, — he’s Martin Ryle's brother-in-law, he would surely know about this, and to my amazement they didn't know a thing, next day. Well, there was this problem of their refusing to give the coordinates of the sources which may have got a bit awkward but it didn’t. But if you look at the history of that, I think they behaved really with the most wonderful scientific detachment over that problem. If Ryle and Hewish had allowed rumors of what they were to have got out then I think the whole situation might have been wrecked. You might or might not disagree with this, but I am quite clear in my opinion. I mean you have only got to see what happened once they had studied it scientifically for six months after, in August I think they got the first indications, six months elapsed before, they had kept the thing absolutely a close secret and I have the very greatest admiration for them for doing that. I mean the whole subject would have been bedraggled and they themselves would have been wrecked by the press and there was enough business about green men even when they were able to publish it with the full statistics. Scientific literature at the present moment is bedeviled by people talking about things and publishing them before they've done a proper scientific study themselves of what's going on and so I don't, I have no antagonistic feeling whatsoever about that and I think that their behavior over the pulsars which they were criticized for and I would very strongly defend them, as having behaved in the traditional scientific manner in which I was brought up. I mean everybody nowadays, they go and make an observation and you read about it in the papers the next day.
Except that in traditional science, looking back over say a century and no further we hadn't got B.B.C. television cameras intruding into your laboratory which adds a…
Well, jolly good luck if you can keep them out. We've had a hell of a job here because of the space business.
Have you personally greatly resented the press and television and radio.
I’m slightly schizophrenic about it, because in the event the publicity media just baled me out. And this is what people, many young people don’t understand. Did you read my account… well I mean there's no need for me to bother saying anything more about that, I mean I think you ... So no I don't bear, not now, we like to think we've got things pretty well under control. Still you know it is difficult though. C P. Snow once wrote that he had no sympathy with people who suffered from publicity because any man who didn't want publicity and got it only had himself to blame. I don’t think that's right. I mean, in a situation like we suffered here, it would have been very, very difficult.
What do you think have been the major achievements of radio astronomy? After all it's only been going on what twenty-five years? What do you think the major achievements are?
Oh gosh. Well, the things that immediately spring to mind are the cosmological aspects of it. By that I don't mean the conclusions that are at present reached about cosmology which I have reservations on the whole lot of them because I don't think nature yields her secrets like that. But first of all the discovery of radio galaxies and then of quasars and the discovery of pulsars are, I think, obviously of tremendous importance. But in some ways they always seem to me of more local importance; I mean this is because of one's interests, I mean it depends on what you are interested in. I mean broadly speaking, why do you do astronomy, why do you do radio astronomy, because it's an obvious and marvelous tool for the exploration of the universe in the widest sense, and the problem, the cosmological problem is one in every sense of the word of very great fascination to people like myself who are not only interested in the science of it but also the philosophical aspects of this. And I think it would be incontestable that the collaboration between the optical and radio astronomers which had led to the successive extensions of our penetration into the universe has really been of decisive importance and it would be very difficult to predict the future but I suspect that one will look back on this, these couple of decades particularly from about 1950 to 1970, or thereabouts, as really one of the great epochs in astronomy. Then on the other hand the whole of the line work, the discovery of the neutral hydrogen, OH [???] although I must confess that personally I get slightly sort of blasé about the endless discovery of new molecules that come in. Nevertheless the fact of the discovery of these molecules is of tremendous importance and of very great importance outside of purely astronomical theory. I mean it may be of immense biological significant. Well there you are, there's a generalized answer. You might ask, how is this reflected in what you do here: in a very straightforward manner, we have spent on the whole, just over about 30% of our time on the interferometric problem which has been our major contribution to the quasars and the radio galaxies, and the radio galaxies, and [???] and about a quarter of our time on line work.
Now there is a, you've done, I know, a lot of study here on quasars and pulsars, on particular sources. Now there is a difference in scientific strategy: quite apart from technique. You mention the Cambridge aperture synthesis as being a technical strategy. There is a difference in scientific strategy between studying these sources for their own interest, for the astrophysical problems posed by them and for the statistical distribution, for the cosmological game which you play with the statistics and distribution of them. Now have you yourself, as the subject has developed here, as you say, you came with radar equipment, thinking about cosmic rays and going on to meteors and then the whole thing developed; have you yourself felt that you have an overall cosmological aim of the same type as Martin Ryle and his group appear to have, in the scientific direction of their work?
Yes, well we have in this, what I think; I mean Hey asked recently what I thought was the major contribution of Jodrell Bank and this is a thing I am always rather reluctant to speak on because we don't want to upset any of my colleagues, but I would have thought that it was incontrovertible, that our major contribution had been the interferometric studies, which were beginning when Hanbury Brown came and has been continued when he left and may I just say a few words about that? They've been important for two reasons. First of all, when we thought we were dealing with extremely small sources and before it was technically possible to get long base lines with the phase correlation interferometer, when we were still dealing with minutes of arc, this led Hanbury Brown to develop the correlation interferometer, and then you had this immensely important experiment which reacted so violently on theoretical physics, the correlation between beams of photons, and then, well first of all the lab experiment which was made here and then the first experiments with the two searchlights which measure the angular diameter of Sirius, and all that was done here, and it’s often forgotten that Hanbury Brown: Stellar interferometer was partly financed by the University of Manchester. However that's alright, he had to go there [???] to do it. But so that’s an offshoot which, of which we are very proud, I mean which I can take a certain amount of pride in the sense in which Blackett would take [???] in us, it is one thing I was able to encourage when I could have stopped it if I wanted to, but it was obviously of enormous importance. And then on the mainline of development, the successive increase in our resolving power which I've done my best to stimulate, having been successively possessed with the immense importance of this from the cosmological point of view. I remember I was fortunate enough to attend both the Solvay conferences I think in 1958 and again in the 1960’s on the evolution and structure of the universe and another one on galaxies. And you know the Solvay conference is in a room like this with two or three dozen people round a table. On both of those occasions, as Palmer will tell you, I came back absolutely determined to shift more and more of this effort over to the extension of the baseline; very difficult to shift the effort of a station like this over. And because it has always been perfectly clear to me that these, quite apart from the statistic work that Ryle has been doing, would be a major contribution to cosmology. I mean you have the problem of the angular diameter variation with red-shift and so on, which remains a vital problem which I'm trying to get Palmer to do now, as soon as we get this telescope back into action. The marvelous offshoot of this, of course, was the incentive which Palmer’s measurements gave to the photography of the source 3C295, redshift of .46. Then this search for the optical correlations of those like 3C43 and 276, I think it was, which he found had even smaller angular diameters. After all that was the stimulus-[coupled with the Cambridge one of the Cambridge declination measurements and I think the Cal Tech R.A. measurements or the other way round, one was accurate and the other wasn’t] which led the people at Palomar to photograph these things. [???]
The first quasar.
Yes, well, I mean but this was discovered as a star, I mean it was Hazard yes, it's true, it was Hazard who had taken over the lunar occultation technique which he developed here which finally triggered off the identification of 273. But the incentive which led to the discovery of the initial blue stellar objects which were thought to be blue stars in 1960 was the interferometric measurements of the diameters here. So I would think this has been our most and I still believe it is going to be very important indeed. It will be one of our major problems when we get going again — this relation between the angular diameters and redshifts.
And these cooperative experiments, the long base-line with the timed phase thing is a; you're one of the major world bases now.
Yes, we are, but of course we lost out on the technique. I mean until up to about a few million wavelengths separation. [???] the arguments of Palmer and so that it wouldn’t be done by persuading [???] who was then head of R.R.E. to let us use [???] to explain our baseline. That’s been a very, very, fruitful collaboration, our relationship with Malvern. But then as you know, we lost out on the technical angle because the Canadians developed before we did the independent [???] technique.
So in a sense you were outflanked…
We were outflanked [???]. Now we’ve done the measurements with Arecibo and this winter quite a few measurements at Gothenburg, using the independent local oscillator technique. To a certain extent we’re outflanked in, if you like to call it, the race for greater and greater resolving powers, but I don’t necessarily think that that is of most importance to cosmology, I think the next stage in the cosmological investigation of this is what I am now trying to get Palmer to do, and this will be the assembly of much more evidence than we already have about the relation between the angular diameters and the redshifts.
Of specific sources?
Yes, I mean we've got well I've forgotten how many it is, we've got about 50 or something like that but you see, it’s always a problem, it's the heterogeneity of the collection, and we want hundreds so that we can get a reasonably homogeneous collection of things that are known to be radio galaxies or quasars. But the point is that this, most of that work can be done with the baselines which we've got with our radio links. It is necessary to get the… I think the… I mean if I was asked to guess I would say that the resolutions of 1/1000 second of arc which we are doing with Arecibo and other people, the Americans are doing, are possibly going to be of the greatest importance to physical understanding of the processes, energy processes, but not necessarily for cosmology. I mean it’s an enormous subject still. And it is an approach which I myself would prefer to the more purely statistical approaches of Ryle, because I've always been bothered about the heterogeneity of the collection that I've had a lot of arguments with Graham Smith about this… however, this is rationalization if you like of what we're doing here.
So you're, well, you're hoping to build up with as you say, the Henry Palmer and the new instrument further statistics of a different type.
Yes, we’ve got some extraordinary good young men here at the present time. I mean you probably haven't seen them but we've got six people here that are absolute stars. Unfortunately we can't keep them. But one of these is a young man who's developed a beautiful new technique, in which he can see, in which a number sources come up, all the sources in the beam just come up as they follow round in low angle.
These are not research members of staff you mean?
Oh these arc research students working in Palmer’s group. They are not all the brilliant ones, I mean R.D. Davies has got a marvelous young man who’s working on the recombination lines at the moment.
Well, yes, the Cambridge people tell us similar tales about their young men at the moment. There's a very, it's become a prestige and high status field.
Yes, you see, a couple of years ago I was in a state of deepest depression about the young people. Oh, I'd no time for them at all. Now I… there are six people here that I shall almost weep when either of them go… I can only keep about one or two of them. They are really very brilliant. And you say that Martin is the same is he?
Well he's such a big group, now, going back there is extra-ordinary feeling because it's grown so much and some of the young people there so clearly of similar caliber — and so here we have this sudden explosion to high status like nuclear physics was at the time I was at the Cavendish which everybody was going into it…
I'm interested that Martin feels that too. I mean if I hadn’t — no if I wasn’t the sort of person who for a number of years had not taken too kindly to the attitude of the young, particularly the ones I'd seen here, I wouldn't be so amazed. Why, I'm glad to be able to say that. No, I think we… if we get this telescope going again in eighteen, months or so, we'll be in good shape.
You've already alluded to your view of Cambridge's achievements and their complementary nature. You'd list their major achievements I take it in development of aperture synthesis and in keeping the lead in the survey work, because they still, I suppose in the world league are up among the leaders in the straightforward business of cataloguing positions and intensities.
I don’t think anybody has ever seriously thought it worthwhile to compete with them at the cataloguing, I mean that goes without saying; it’s an absolute classic piece of work for all time. And of course, I've known a few things that delighted me more than the discover of pulsars and the way in which they were discovered because it just hammered home in a way that I could never have hammered home to all my young people here, that there are many, many things in the heavens still to be discovered. But it's very difficult to drive the lesson home. I mean they're willing enough to tear off in the investigation of pulsars but they still program everything on the computers. I mean, I argue that if Hewish had had all his stuff going into a computer of the type that a lot of my people like to get their stuff going, pulsars would have never been discovered. J.G. Davies is prepared to argue about that, but I don’t know. It is a worrying thing about the present highly technical developments. There are two worrying things, one is that a lot of the people outside, I imagine that Martin has the same problem as I do, that it’s easier — they enjoy the techniques more than the struggle of trying to understand the universe. And the other thing is even those who do astronomy with them, they may well be programming out major discoveries.
Yes, you only find what you expect to find in the established field, and you feel that somehow the pioneering area in which your expectations weren’t so firm and therefore what came was more easily acceptable had gone.
Oh, the subject of quasars, you see one of these young people, Brown, a good young man, has published — week before last — in Nature two bright, quite bright quasi-stellar sources, one of which has always been regarded to have been a variable star.
Yes, I spotted that letter, yes. When did you first start thinking of yourself as a radio astronomer as opposed to a physicist? You came here in the department of physics.
Difficult, after all, radio astronomy, the term was not coined of course, for some years after we came here.
Well Hey used it in that review article of '49.
Yes, I don't know who used it first but Clegg and I published a book with the title Radio Astronomy about that time. When did I first… well, I don’t know. I suppose when I became Professor of Radio Astronomy.
But until that time your major interest had been physics or would you, when pushed, have described yourself as an astronomer, when working on meteors?
Well, I never had any training in astronomy at all, so I mean I… I never attended any formal lectures in Astronomy. So I am a physicist, I suppose.
Everybody finds it a very difficult question to answer.
What, when they first…?
Yes, because you see one of the things we're interested in is you might say the emergence of certain terms like molecular biology as a social category, I mean at what point the people who previously thought of themselves as biochemists or crystallographers suddenly think of themselves as molecular biologists.
Well, I cannot say exactly the year, but it was clearly sometime between the end of the war and 1950, and there's five or six marvelous years there when everything was sort of blowing up, that is when learned one’s astronomy. But I suppose like many young people in the 1930's, I was fascinated in an amateur sense by astronomy.
Do you see radio astronomy as a separate subject, in some definable specifiable way, from astronomy?
You think it merges entirely with…
Well I see it neither separate from astronomy or from physics or from geophysics. I think that it would be a grievous error to behave as though they were separate. After all many of the major developments in what I've been talking about have been because of the collaboration between optical astronomers and radio astronomers. I think this goes all along the line; it is the collaboration between the theorists, theoretical physicists or theoretical astrophysicists on the one hand and the purely practical optical people on the other with radio astronomers which has caused this dramatic progress recently. Well do you dispute that?
Well we asked Martin Ryle this and Martin Ryle gave a very interesting answer in which he characterized the distinctiveness of radio astronomy as being something to do with the combination of the way that ideas emerge through the technique so that…
Yes, but you see my worry is that but for the conflict and collaboration with these other subjects radio astronomy would become technique.
It would be a completely separate thing.
Well and would be just a glorified technique.
But another way of putting it is to say that in the early day the very early days, people could think of the radio universe as being quite different from the optical one. Well, I remember in 1955 when I was just joining the group at Cambridge I went up to a camp actually with a friend of mine who'd been a navigator in the R.A.F. and who knew a lot about the stars and he could, I mean I was going to be an astronomer so they said, but I couldn't say the first thing about the visible universe whereas he knew it. And one could think of the two things as being entirely separate, and then there comes a time in which you have to see them as being the same because that’s where the important problems are, in relating the two.
Oh, but it’s not only that, I mean it's the whole spectrum that’s involved now, I don’t think you can separate them. If you're going to take the line that optical astronomy and radio astronomy are diverse, separate in their interests, then you must, take the same view about rays and x-rays and even extreme ultra-violet and extreme infrared. Well, no, I don't think there's any future in that.
Still, could I put it another way? I've been plowing through the astrophysical journals, twenty years’ worth of astrophysical journals I read in a week, a thousand pages to a volume or something. Now the overriding impression you get there, you get an intrusion of radio based papers. It starts around 1951 in Astrophysical Journal and it builds up to about 15% to 20% around 1966, but the vast impression you get is an unrolling of a whole series of studies within the limits set by traditional astronomy, because there's a vast amount of Chandrasekhar and all his students and so on, theoretical problems in all kinds of areas you get all this, some variable stars in this constellation catalogued and talked about and so on, [???] lots and lots on this, distances and so on, and you get the impression that the whole of this was being optical astronomy, which is determined by its history and its techniques and the whole of its ideas, and radio astronomy coming in is quite a different sort of thing, and altering in some way the basis of theory and the outlook, so that radio astronomy intruding into optical astronomy shifts, so that you could say that radio astronomy was different from the traditional optical astronomy in that sense. It has shifted focusses, it has shifted interests and the theoretical problems have changed and so on. Now you would agree that there was something of this, that radio astronomy is distinctive…
Yes, I said just now, I think the important, the significant part of the astronomical developments in the last two decades have been the collaborative regions.
And it's in the collaboration that changes have occurred? The optical astronomers have changed.
Yes, I was thinking particularly of this in the discovery of radio galaxies and quasars. This is where the most dramatic changes in astronomy have occurred. And also in the sun, but in the case of the sun you had… there it is — evident that the whole spectrum is involved. After all, the physics of the sun, solar physics, was completely revolutionized by radio astronomy, I mean that is the first and most obvious example, and it remains a very good example of the integration over the whole spectrum. I think the case there is very, I think in the case of the sun it has now become so obvious that one almost forgets to cite it. And the other obvious and glorious case is in the cosmological problem which after all you’ve only got to look at the extent of the penetration into the universe when the radio began to infiltrate and to see this penetration would not have been increased if the optical people had been left on their own because they wouldn’t have had the incentive to…
No they wouldn't have had the subject matter to talk over. Do you believe… well it's clear that radio has made a tremendous contribution to solar physics and so on and you used the word revolutionized? That would, in my mind, imply, that if you went back to '45 you know before the solar thing began and were able to resurrect a theoretician from that era and now show him –- that he would be very surprised that the whole concepts and theories that he started off with have been quite changed. You think this is so?
Yes, oh undoubtedly. I mean our whole understanding of the solar atmosphere is quite different and the blowing away of the material of the sun. No, I think one of the very great and clear-cut revolutions which has occurred in astronomy is the interplanetary situation, by that I include the sun, its interaction with the planets and the earth. I mean this was first of all stimulated by the impact of the radio observations and then of course, subsequently the space observations.
In galactic structure Rod Davis said to us not surprisingly that felt the most important contribution of radio was here… but then that's not revolutionizing, the radio data fits onto previous ideas, explains it, consolidates it, fills the gaps and so on.
It is perhaps one of the most clear cut and one of the most elegant pieces of work for which radio astronomy has been responsible. I mean that combined Dutch and Australian maps of the spiral structure of the galaxy. In the historical perspective it will probably go down as one of the most beautiful isolated contributions to …
But nobody really sat up and said, my goodness, I am surprised to see that.
No, no, just confirmed what was obvious oddly enough from our sight of other galaxies.
But you think the solar people were surprised, and of course the quasars, the pulsars, cosmology is a surprise almost every day.
Yes, yes, well, I think… if you go back to 1945 there was no understanding, no real understanding about the electron temperature in the solar corona. Our only avenue for investigating the corona was during the total eclipses and, certainly no feeling at all for the interaction of the solar corona with the interplanetary medium or its extent in the radio spectrum. And, of course, if one looks ahead a bit one feels that as one’s instrumentation improves, the same sort of situation will develop with the stars in their evolutionary context.