Interview with Cyril Hazard on 3 June 1981

Sullivan: 00:01

Okay. This is continuing with Cyril Hazard on 3rd June, 1981, continuing that is from March 1973 in Groningen and continuing in September 1978, also here at the Institute of Astronomy in Cambridge. The Mark I telescope, I did ask you before about did you think that this was the obvious way to go? And you said, yes, well, you had good success with the 218-foot. And, obviously, it'd be nice to have a steerable telescope [for the?] pointing and so forth. But overall, did you feel that that was the way to put a lot of money in Jodrell Bank? Would you have been in favor of that? Or would you have favored a different approach?

Hazard: 00:51

I think probably at that time, that I wasn't sufficiently involved in that type of thinking.

Sullivan: 00:58

Okay, since you were not a leader, just a junior staff member, you're saying.

Hazard: 01:00

That's right. That's right. I think that we were keen on it, Hanbury Brown, myself, but only in the sense, I think, that we had been using the other one. Obviously, we get a tremendous amount of stuff if you had a fully steerable one. The other thing is, I mean, I do remember I said Hanbury Brown once, maybe over that [inaudible]. Another way would be to build two lines of things and cross them. I didn't work out the details. But this sort of thing, I think, that idea must have occurred to many people at the time, that you could build some sort of interferometer, I don’t know how you would do it, I mean, I wasn't thinking of any of the details. But I think the sort of thing that happened, though, was that we really weren't doing any interferometry at all at the time. And Jennison was doing some of the stuff in [inaudible].

Sullivan: 02:00

But there was a specialized kind of [crosstalk].

Hazard: 02:02

This is up to 1950. I mean, [inaudible] this thing was [inaudible], of course.

Sullivan: 02:06

Around 50s.

Hazard: 02:07

Almost concurrently with they're bringing into operation out of the [inaudible].

Sullivan: 02:14

Almost, yes.

Hazard: 02:15

I mean, [crosstalk].

Sullivan: 02:16

It's a year or two later, I think.

Hazard: 02:17

Yeah, I mean, but the ideas, I think, were probably [inaudible]. See, Clegg was one of the main [movers?]. Clegg gets squeezed out of a lot of things.

Sullivan: 02:25

Well, I interviewed him over the phone just a week ago, so.

Hazard: 02:27

Yeah.

Hazard: 02:27

Is he still walking around?

Sullivan: 02:29

He's still walking around, yes. He's retired--

Hazard: 02:31

What [inaudible]?

Sullivan: 02:31

--down there [inaudible].

Hazard: 02:33

How does he feel about it?

Sullivan: 02:35

Well, he basically left because he felt the place was getting to be a big science. And then he would lose his hands-on ability, which he very much liked and so forth. But I think he sort of took it philosophically, in that it was inevitable that you had to go to bigger things. But personally [inaudible]--

Hazard: 02:56

I think [inaudible]. I think there was probably some context as well. Probably, he wasn't happy about other things as well. But, I mean, he himself, I think, did the design essentially. Have you seen the--

Sullivan: 03:15

The [inaudible]?

Hazard: 03:15

--the [inaudible]?

Sullivan: 03:17

Oh, I've seen that one.

Sullivan: 03:17

Oh, yes.

Hazard: 03:18

[inaudible] seen most of that is Clegg, I think. I mean, the design of the telescope, and so on. No, I would say at that particular time, everybody-- well, there weren't many people doing radio astronomy. I mean, essentially, the person-- and, of course, at Jodrell Bank there had to be, I think, looked at in rather different terms to where you would look at the Cambridge setup, in the sense that the actual effort on extragalactic work at that particular time, or on radio [inaudible], [inaudible] extragalactic specifically. It was only a relatively small part of the operation and only grew after that. [crosstalk] before. So I think also there may have been a difference, that perhaps they were more in contact down here with theoreticians and so on.

Sullivan: 04:23

You think so?

Hazard: 04:24

Well, at least it was [inaudible] and so on. [inaudible].

Sullivan: 04:27

That was a strange kind of contact, but--

Hazard: 04:29

Oh, but it's still a contact of some type, I think.

Sullivan: 04:36

There was no one like that at Manchester University.

Hazard: 04:39

Well, [inaudible] was in [inaudible] about that time.

Sullivan: 04:45

[inaudible] was a little bit later, I guess.

Hazard: 04:47

[inaudible] later, I think. The input came in. Yes, and I think that--

Sullivan: 04:53

Was [inaudible] there, even for a short while?

Hazard: 04:55

[inaudible] came, but [inaudible] came quite a bit later on. I can't remember when he came. Come in. I can't remember when [inaudible]-- did [inaudible] come '54 or '57?

Sullivan: 05:04

I'm not sure. I would have thought it would be around that time, but of course, you were away for three years, so it might have been while you were away.

Hazard: 05:10

No, he came when I was-- I think it was about '57. I think it would be that time. I think he came when-- when I got back, he was there.

Sullivan: 05:16

But the point was you felt you weren't having much contact with these people, even if they were there.

Hazard: 05:21

Well, that was later on. I think that things had changed by '57 or so. And I think when I went back again-- I don't think [inaudible], but I'd changed. We were doing different things by then, and this thing was moving faster by then. But up to '54, which is [inaudible] you were talking about, I don't think that-- we didn't know any [inaudible]. I think that was the thing.

Sullivan: 05:52

Okay. But now, here's the irony of it that I wanted to ask about, is that it seems like right from the very beginning, that all of your work, along with Hanbury Brown, was strongly to do with optical objects. You were looking for the optical nebulae, you were always trying to correlate, you set up radio magnitude scales.

Hazard: 06:11

Yes, that's right.

Sullivan: 06:13

Why was it [inaudible]?

Hazard: 06:14

I don't know, really.

Sullivan: 06:18

Neither of you were trained as optical astronomers, and there were no optical astronomers around.

Hazard: 06:22

It shows in some of the early stuff [crosstalk], I think.

Sullivan: 06:26

But why was it that you were making this effort?

Hazard: 06:32

I think it was historical in the sense that we started off with looking at M31, of course, which is what it was about [inaudible] we first came back, and I think that it followed on from there. I don't know, but it probably accounts for why I switched later on.

Sullivan: 06:54

To optical astronomy?

Hazard: 06:55

Yeah. I mean, my interest moved away because-- I think that the work did lead in that direction.

Sullivan: 07:04

Okay. Well, another question along these lines is Jodrell Bank obviously has been one of the leading radio astronomy labs through the '50s. What do you think has been the main key to that success? Which components?

Hazard: 07:27

What do you think is the success? I mean, that is the first thing.

Sullivan: 07:31

Well, I think your work with Hanbury Brown was quite good in distinguishing the radio galaxies, as we call them now, from normal nebulae and Class I and Class II. And Mills was doing some of this too, but nevertheless, [crosstalk].

Hazard: 07:48

What I meant by that is that-- I think that I just wanted to get clear-- [inaudible] because I can look at a smaller target the whole operation and--

Sullivan: 08:02

Well, I'm also thinking of the radar work. That was lunar radar work. That was interesting. Also, ionospheric work, establishing the nature of the simulations. And of course, there was a lot of meteor radar, which is sort of a separate field.

Hazard: 08:16

See, I feel that, personally, that the success of Jodrell Bank, the main success of Jodrell Bank, wasn't so much in the work that was done there, although I think that a lot of that was important. A lot of very good stuff was done, as on the radar work on the meteor stuff I think the very big impact that talked about--

Sullivan: 08:39

I forgot to mention the intensity interferometer also.

Hazard: 08:41

And then to develop an intensity interferometer, well--

Sullivan: 08:45

What do you feel is the--

Hazard: 08:47

I think the fertilization of the whole field, I think that the impact of people from Jodrell Bank in radio astronomy as a whole, has very large. I think probably larger than almost any other group, maybe except some of the Australians. I think if you look around the world and what the various establishments, and check who is there, then I think you've got a very good chance of finding an old Jodrell Bank person there. And so I think that the sum total of the amount of work which has been done by people who have spent some time with Jodrell-- it's very large.

Sullivan: 09:26

So it's been a training ground.

Hazard: 09:28

I think it's been a very good training ground and I think that that accounts for some of the other stuff that you're talking about is that it wasn't a very structured place. It was split up into groups. Fairly small groups who operated almost independently. And I think one of Lovell's great strengths was that he really didn't interfere with anybody and they let everybody do what they wanted. That's what I've been making a comparison. I mean Edge and all these people have written these comparisons of various places, I don't know how true they really are because I think we have to be in the system to see how it was. But as I remember Jodrell Bank in the early days, I mean one of the, I would say the more striking thing about it, was that it was a very lively, active, and very friendly place. We all enjoyed ourselves. I think that was the-- it was a big game I think. And we really did enjoy ourselves. We were out there in the country and everybody, although they're in different groups, scattered around the field and working on different things did interact very strongly.

Sullivan: 10:48

Interacting in all things [crosstalk] building aerials or--

Hazard: 10:52

Oh, not talking with each other because we were mixed in meteor groups. We had [inaudible] meteor stuff on the same path as us and so on. I think that we-- no, I mean I just meant even to think that we would get out on a nice day and take [inaudible] all move out of the fields and our antennas and so on. It really was a socially-- in the place itself. I don't think necessarily outside we didn't mix very much but the place itself is [inaudible]. I think that there was no line to follow. We didn't have any particular--

Sullivan: 11:26

No vision, so to speak.

Hazard: 11:27

No, I don't think we had a vision in that sense. And I think that because we were too small at that time, which maybe it had its faults, of course, later on. I think by building a general purpose instrument like the 250 foot and going for the general purpose type instruments, to some extent, it can slow up the development of a particular line, I think. Which is a special purpose instrument which is built by everybody. As the [inaudible] focus the attention much more closely on a problem. And I think at that time, [inaudible] we were looking for problems, I suppose, and [inaudible] dictates a different type of approach.

Sullivan: 12:15

But in that sense, it was really a continuation of the lack of one line beforehand because now everyone could do his own little thing on the big dish.

Hazard: 12:23

On the big dish and I think because that was only true, I would say, up to about the coming of the big dish because I think that with the increase in information and so on, I think the integration over the next several years of radio astronomy, gradually coming into the mainstream, and its real impact on astronomy coming up to [inaudible] impact on astronomy as such. Not many optical astronomers were taking a great deal of notice but after they [inaudible] mid-1950s it was starting to get integrated into the system and the whole thing was starting to change, I think. And I think that the radio astronomers were gradually getting more and more involved in the astronomy and so on [inaudible]. I would say still to some extent that when I was learning some electronic engineering the first few years working on [inaudible] to some extent [inaudible] more interested in doing some of that sort of thing than what came out [inaudible]. You could see, it was quite a sense of achievement when we built a receiver and put it [on the antenna?]. You got a source coming through. It seems ridiculous now, but even to get the signal coming through, we thought that it was an achievement. And you can't get that sense of achievement now, of course.

Sullivan: 13:51

It has to come now from the astronomy [inaudible].

Hazard: 13:53

It has to come from the astronomy now. In the beginning, I think there was this sense of achievement. You were building all your own equipment. And of course, Jodrell has always done that and I think that's another sense where it's different to many places. And maybe overdid it, I think, in the beginning of necessity because there was no money.

Sullivan: 14:11

Well, I'm not sure it's different from other places at that time, though. Radiophysics in Sydney, of course, did that and [inaudible] Cambridge did that.

Hazard: 14:20

Yeah. I think it's gone on longer doing that [crosstalk]. I think [crosstalk]--

Sullivan: 14:22

Oh, I see. You're talking about through the '60s and now, or--

Hazard: 14:25

Well, I think that [inaudible] Davis still designs the computer things with telescopes and so on, a lot of what is pretty--

Sullivan: 14:35

What era would you say that kind of approach became less profitable if you were interested in [crosstalk]?

Hazard: 14:42

I think it was starting to get less profitable I think towards the end of the '50s because I think that-- well, you had, you had you the early radio astronomers, the successful ones, I think, Hanbury Brown, Mills, Ryle, I think Pawsey probably is one, quite sure, were engineers, an engineering background because it was the-- I mean, initial [inaudible] application of engineering to astronomy and the problems were technical in the beginning. So it was that aspect of it, I think, that was interesting. I think there were some interesting problems. Because I mean even stabilized power supply [inaudible] particularly in existence in those days, things like that. So you had [inaudible] power supply--

Sullivan: 15:38

[crosstalk] that was a contribution to electronics, just learning how to--

Hazard: 15:43

That's right, that's right. So you had to be-- at the beginning, it electronics that was the thing, I think. But the engineers, of course, the engineering aspects were very important in developing the new techniques and so on because it required a pretty profound understanding of noise and stuff like that [inaudible]. As the techniques developed and I think the information began to come in bigger amounts, then I think that you had-- the problem started to shift and, plus the fact I think that the people who were recruited, apart from, say, Jerry Hawkins, perhaps, who I think was one of the people who had any knowledge of astronomy in the beginning. The at Jodrell anyhow, the people that [inaudible] were physics--

Hazard: 16:37

The [inaudible] was from the physics department and so apart from people, I think, who had their own interest in electronics when people were coming into what was a fairly technical subject with very little knowledge of electronics to begin with, no knowledge of antennas and so on in general, so you had to start to learn that part of the subject first as well. Now, as the stuff got more and more complicated, I think this became a pretty unprofitable sort of way to spend your time, and it was recognized, obviously, by the hiring of [inaudible], which I think was on about '57 or something like that. Now obviously, the climate wasn't right. I mean, to do that, [inaudible] obviously because I don't think-- well, he didn't stay very long. I mean, I don't know what happened. Because it was difficult for an optical astronomer to fit into this system which still hadn't made the whole-hearted change over to an astronomical [inaudible]. Now I think it's quite easy.

Sullivan: 17:46

Yeah. Well, let me ask about-- it seems a bit peculiar to me to have some passive observations going on and you are doing a large fraction of them but not [inaudible].

Hazard: 00:34

It wasn't a major problem. It just meant you had to have stuff you ought to know and you had to have it there.

Sullivan: 00:42

Well, let me ask a question, which you were touching on there. Mainly, what do you think, going up until the early '60s, was the major thing that radio astronomy-- or things radio astronomy contributed to the development of astronomy as a whole?

Hazard: 00:59

In retrospect, you mean [crosstalk]--

Sullivan: 01:01

Yeah, how do you see it now?

Hazard: 01:02

Oh, I think the recognition of the-- it was all leading up to the role of the nucleus, I think, in the galaxy inn retrospect. I mean, I think one can say that the double radio sources and all that sort of thing was pointing to the fact that you had an active nucleus in the galaxy looking back. I mean obviously, the subject had been dominated to a big extent by the cosmological aspects as well. I mean, I think that once it was realized that these things were very distant and you could really do cosmology at a distance-- and that's played a very large role. Now, I'm not quite sure, I mean, whether that's been terribly fruitful. I mean looking at what's been achieved by the amount of effort that's gone into that particular part of it, that the radio sources evolve, and so on, I think we know now how at least they evolve and that there are density changes and so on. That I think--

Sullivan: 02:14

So you're not sure that that has really given us a greater understanding of cosmology, but in any case, it certainly had a large impact on cosmology and the way it was done. Is that what you're saying?

Hazard: 02:27

Well, I think that a lot of radio astronomy, the emphasis was on cosmology, partly because of the controversy of the steady state--

Sullivan: 02:37

Right. Well, I want to come back to that question.

Hazard: 02:39

--and that one. And perhaps one associates a lot of it too much with that aspect of it because perhaps it was much more important, I think, in recognizing what was going on in galaxies and so on, that these simply passing objects is sitting there. And perhaps I think if we had tried to make the jump now, right the way out and got very distant things, we might've built up a better picture of what was going on more locally and set a better foundation for some of this, but.

Sullivan: 03:15

It sounds good.

Hazard: 03:18

So it led to the-- it was important I think because it started and led eventually to the recognition of different types of objects [inaudible] at least, we're really aware of, I think. I mean, [inaudible] galaxies and so on, and obviously being found beforehand, but the role really wasn't recognized at that time. It led to the recognition of these type of objects, the interesting objects, which brought-- it was a method of locating potentially interesting parts of the sky as well, the radio sky and so on.

Sullivan: 03:56

Do you see any contributions and the way radio astronomy was done, the attitude or the methodology is having influence on optical astronomy.

Hazard: 04:09

Not until very recently, I don't think.

Sullivan: 04:12

What do you mean by very recently?

Hazard: 04:17

Well, I don't know whether it had an impact or not. I would say that dealing with people, with radio astronomy, by bringing into optical astronomy, people who had very strong engineering backgrounds and so on and very familiar with the extremely complicated radio astronomy techniques which were developing by the 1960s, and so on, had a big impact in probably on the way telescopes and so on were designed. I mean, I think it was probably a bit frightening to an old optical astronomer to contemplate, highly sophisticated guidance of telescope was [inaudible]. I think that that sort of stuff, computer things, seem to come completely to some people in radio astronomy.

Sullivan: 05:22

So it was late '60s, really, before that had an impact?

Hazard: 05:26

I'm not quite sure. Well, the Parkes radio telescope, regarding Parkes radio telescope, and it must have had some [influence on the AT?].

Sullivan: 05:36

Well, that's John Bolton [crosstalk]. He was on the design committee.

Hazard: 05:40

So he had to [because they?] designed that. [inaudible] design of these.

Sullivan: 05:46

But you don't think that radio astronomy was influencing how the optical people did their research or how they thought about things very much in the '50s?

Hazard: 05:54

I don't think so. I don't think so. I mean, I think [inaudible] to accept that they're good, I think, obviously, yeah, [inaudible], I mean. And obviously, [inaudible] cost. [inaudible] I'm not sure I think [inaudible] did more than that. So the one or two people that were--

Sullivan: 06:19

These were the exceptions?

Hazard: 06:20

[crosstalk] exception. I think it is probably the way that-- it's probably an accident as well. Not so much an accident. I think that radio astronomy, to some extent, got itself going, for historical reasons, in England and Australia, who didn't have optical telescopes. And therefore, they got well on the way because you could do-- because there was no competition. All of [the people?] who were getting into astronomy worked on radio telescopes and so on, whereas when you had the big optical telescope, after all the 200-inch, had just come into operation in Palomar and so on. So it was a big research, of course, in optical astronomy at the time.

Sullivan: 07:03

In the States?

Hazard: 07:03

In the States, and I think this is possibly why radio astronomy never really got cracking in the States until a long time afterwards. And so, by that very nature, a physical barrier [inaudible] to fly around [inaudible].

Sullivan: 07:19

In other words, the tradition of observing on telescopes. [crosstalk] you used your own instrument.

Hazard: 07:24

That's right. That's right. So it's to a certain extent, I think, these two things developed separately, radio astronomy where there wasn't any optical astronomy, and the optical astronomy where the optical astronomy was [inaudible] developed for some reason. And the breakthrough there, of course, to some extent, was [of course?]-- on the Australian side was John Bolton then going to Caltech.

Sullivan: 07:54

In terms of helping you as--?

Hazard: 07:56

Well, I'm not quite sure whether it was the first one but that, but in the midst of extragalactic work and so on, that was probably the first real sort of working contacts between the optic and the radio. I should think where they were in the same building [inaudible] same place and collaborating correctly.

Sullivan: 08:16

Yeah. The only other close association between optical and radio had been at Harvard, which was only 20 centimeters [crosstalk]--

Hazard: 08:24

On that sort of thing, the galactic structure, I think forms a separate.

Sullivan: 08:30

But [correct me?], I think that's a fair statement, right? Just an odd question here. In a previous interview, you mentioned Hanbury Brown's drift experiment.

Hazard: 08:42

Did I?

Sullivan: 08:42

Which is how I came across it, which was never done.

Hazard: 08:46

Oh, sorry. I'll tell you what was. When--

Sullivan: 08:48

When was that?

Hazard: 08:49

No. When I went Jodrell originally, I went about the same time Hanbury Brown arrived. Now I worked with Alan Maxwell and Gordon Little for a few months. And then I went over to work with Hanbury Brown on the 210 foot and the project, which he'd inherited from Vic Hughes who was doing radar stuff and so on as well, was to use the 210 foot fixed telescope to investigate the spectral variations in a strip sky in the zenith, at different frequencies in which we'd look at 75 Herz, and something else. And I think the big decision to [inaudible] the distribution in this [crosstalk] it's just as the sky drifted round.

Sullivan: 09:49

So the drift refers to just drift scans, so.

Hazard: 09:52

Drift scans, yeah. That was what we started off to do. And, it was when it originally arrived Hanbury Brown had suggested that we could-- I think possibly based on [inaudible] work, I'm not very familiar with the very early stuff, that we could detect M31 and [inaudible] the telescope could be tipped over that far. And so that we start to tip the telescope over by the [inaudible] from screwing cables and tipping it over.

Sullivan: 10:28

What can you describe to me exactly what you had to do and how long it took to tilt that telescope?

Hazard: 10:33

It would take most of the day to tip it a few degrees.

Sullivan: 10:43

And how many people?

Hazard: 10:44

Two of us.

Sullivan: 10:45

And what did you have to do?

Hazard: 10:47

Well, it was guided by three sets of cables based equally around the thing. And that what we'd do is there was one cable, one set of cables would be pretty well north, south, I think. So there's one set of cables would be there. [inaudible] cables. And what we would do is, one of us would go to each side of the telescope to [inaudible] cables. Say one on the east and one on the west. And we slacken off these cables with, there'd be about six cables. I think running up the top hikes a mask, and we'd slacken these cables off by a certain amount. And then we'd go around to the other cables and we'd start to release them, pull them in the other direction, the north-south direction and tip the thing over. And of course, when we did this, the whole thing started bending. So [inaudible] you have to keep on trying to keep the thing reasonably straight and hoping it wouldn't break any particular time. And I can't remember how long it took to tip it over to 20 degrees to get the-- [inaudible] it was 12 to 15 degrees to get to M31. But typically, we would change it by the order of the degree or so in a day. And that would take us most probably a whole afternoon overall because it would be long [inaudible] and then--

Sullivan: 12:21

Then how did you know where you were, or?

Hazard: 12:23

Well, then we put a couple of theodolites down in the end at-- well, to be smaller [inaudible] because when we managed to position on [inaudible] and then just left out what angles tipped over, and we had some relationship between the angle of tilt in some papers.

Sullivan: 12:49

Right. Well, you work that out of your thesis?

Hazard: 12:51

Yeah. Something like that.

Sullivan: 12:54

Okay. It turns out, by the way, that that detection at [inaudible] point was certainly experience. I mean, he came up with a hurry, way too much intensity at his frequency, which is just about the same 0.6 [inaudible].

Hazard: 13:09

That's right. I think so, yeah.

Sullivan: 13:10

But in any case, that was part of the motivation, apparently.

Hazard: 13:13

I think that was totally motivation.

Sullivan: 13:17

And you realized that in person. I'm quite sure you discuss that in here in your [crosstalk].

Hazard: 13:27

I don't know whether they discussed it. We didn't [inaudible] detect it. That's the [crosstalk]. That's the [crosstalk].

Sullivan: 13:27

Yeah, yeah. Well, because you had a much weaker signal than his would have predicted. Okay. Well, now I'd like to jump to the whole business of the log N - log S accounts, the 2C surveys, and so forth. And at least the one place where you publish something on this was in an article with Walsh in '59, which was also presented at the Paris symposium. And basically, it seems that you had an interferometer survey and a single dish survey. And you compared these to see what the reliability was. And you found that with a certain level of-- the level that you couldn't trust. And that corresponded to 1 in every 25 beams or something. Now, was that the first indication that you had to have such a low density of sources before it was reliable, or?

Hazard: 14:26

I can't remember. But there were problems with the beam, which I knew a long time before that, certainly. And I'll tell you how that happened. I don't know whether we've published this? Yes, we did manage to publish a paper where we discussed the model of the galaxy in Philosophical Magazine. What happened was Piddington had published a set of papers, I think, in which he claimed that the width of the galaxy seeing across the galaxy was a function of frequency. And I remember looking at it one night and saying, "I'm looking at something odd here," because the width he is getting is the beam in every case. And then we realized that he couldn't go up with all the beam widths. I mean, we didn't give much [inaudible]. And I can't remember what we did about that. But we realized then that all these restoration techniques when there was serious problems with the beam widths.

Hazard: 15:43

Now, why we got involved in the-- I think that it happened because-- I mean, other people did come about the same time, to the same conclusion, [inaudible]. But we did not know anything about that, the [inaudible] and what happened was we, I'd been away from Jodrell, and I went back and I originally started working with Palmer on the on the interferometer. And I sort of designed some [inaudible] for that and [inaudible], I drifted back into this, I went to work with Dennis Walsh on, or back on the fixed one, which has now got a [inaudible], which you could, you could press a button and move the it'd been a new center mass constructed 210 foot. And you could now just automatically move it up and down. And we decided for some reason or other to do an interferometry survey. Of the sources at 92 megahertz. [inaudible]

Sullivan: 16:58

So you're not sure that the motivation to do that really was to investigate this problem?

Hazard: 17:07

That's what I can't remember now. Have you talked to Dennis about it?

Sullivan: 17:13

Well, I undoubtedly did. I can't remember to be honest, it was many years ago that I interviewed him.

Hazard: 17:19

I'm trying to think. No, I've got to- I've got the feeling that we did it, that we did it deliberately to investigate the problem. That's the way I'm trying to think. Yes, we did. We realized that we did do it to investigate the problem. But I'm trying to remember why now?

Sullivan: 17:52

Well, it was a very big controversy at that time.

Hazard: 17:58

Well, I can't remember-- yes, but I can't—confusion wasn't the big issue was at the time.

Sullivan: 18:12

Well, I think so.

Hazard: 18:16

See, I remember when Scheuer came to Jodrell to talk about some of this stuff. And that was [crosstalk]. Yeah. We said to him, then--

Sullivan: 18:29

Now, this would be, when now, before you went into the army?

Hazard: 18:35

‘57 or something, when the first, when the survey, the 2C first came out.

Sullivan: 18:39

That was ‘54 or ‘55.

Hazard: 18:41

Well, alright, so it must have been about ‘57 by the-- I can't remember exactly.

Sullivan: 18:47

But now you're talking about Scheuer coming up in ‘57 or so.

Hazard: 18:51

But I remember when this thing first came up and they were first [inaudible] involved the results. And so on, on, he came, actually discussed the [inaudible], what they've been doing up there, right. Okay. And we said to him then that the thing was confusion-limited. And he, I remember him saying then, which was the usual thing, that there was less than one [inaudible] beam area. And we knew at the time that the problem was much more serious than that. I can't remember why, but we knew. That's the trouble. We knew that the problem was much more serious. Now some of the problems had crept up earlier on, because it certainly before 1954, we'd found this, all these, all these sources in the [galactic plane?] And we, when Ryle was up there and some others, they hadn't found them in the [inaudible], in the interferometer surveys, and they never [inaudible]. They were real. And we checked some of these out there with if I looking for, by using the interferometer and so on, which was the first time we really got involved in any this stuff. And they were, they were a bit [inaudible]. So it was interesting, I think, from [inaudible] in the differences as to what you were seeing with interferometers and what you saw in the pencil beams anyhow. So we've had some interest in that sort of problem. The were differences turning up between the two types of observation. And I think which we wanted to investigate.

Sullivan: 20:44

Now, why had not Ryle seen--?

Hazard: 20:48

Because they were extended.

Sullivan: 20:49

Because they were extended, okay.

Hazard: 20:49

Now it's because they were extended. Okay. It's rather interesting actually, before I went, I left Jodrell in about ‘54. I'd looked at all these things. I'd measured all the angle size actually, and I didn't publish it, but I'd measured because it's little bit difficult to measure half [inaudible] and so on. But in fact, when I was away, they measured them at Jodrell using the interferometer and there were the [same findings?]. I remember when I went back, I just [inaudible]. And almost my stuff was still there. And just opened the stuff and there were [all these angular sizes?] I written down on a piece of paper, which were all right, but I wasn't confident enough then to realize that. I think, I was leaving anyhow and time [inaudible], but in fact, we realized the source of [iaudible], one-degree being [inaudible].

Sullivan: 21:36

So you had had this history of being interested in this question. And this was another attempt do it, but I don't know of any other attempt where the same observers did both an interferometer and a single dish survey to try to sort this out.

Hazard: 21:49

No, I think that's why we did it. I think we decided to try and sort out that way.

Sullivan: 21:55

And now do you remember this paper having much of an impact at either the Paris symposium?

Hazard: 21:58

There was quite a lot of discussion about it. There was a lot, a tremendous lot of discussion at the Paris symposium.

Sullivan: 22:05

Can you tell me your recollections of that meeting? I've always thought that was-- I wish I could have been at that meeting myself. It seems to me like it must have been a very interesting meeting.

Hazard: 22:15

Yeah, well, yeah, there was a lot of discussion after the talk, and there was an awful lot of argument on the floor, [inaudible] argument [inaudible] they all started arguing [laughter]. It was Mills, and [inaudible] was there. Dennison was involved. [inaudible] started getting into a lot of the arguments then as to what iterferometers really did see and what they were missing and so on. And so a lot of the stuff which was solved in [inaudible] did surface at that time and the discussion-- it was all the usual discussion about extended sources, whether they were playing a role, and so on. I don't think actually, that it actually-- there was some discussion as to what interferometers were seeing. I don't think that there was any clear good answer or anybody really putting forward the [inaudible] by confusion and so on at that time. [inaudible] the whole thing got into a long, involved argument about the merits and the [inaudible] if I remember rightly, [interferometer?] and so on. And [inaudible] the ground is really [inaudible].

Sullivan: 23:36

Oh, and do you remember that there was also, obviously because the cosmological implications of the different surveys were different and therefore, that was entering into the discussion?

Hazard: 23:47

Well, I mean, that's right. I mean, there were the differences if I remember rightly arguing for what the Mills was [inaudible] so on, and things like that. I think the argument basically was between the Australians and the Cambridge group, and we were to some extent not directly involved in the sense that we didn't have a deep personal commitment in the result. Although we didn't believe [inaudible]-- we were very dubious about the interferometer.

Sullivan: 24:27

Well, because your results here were favoring the Mills--

Hazard: 24:28

That's right. And I think we've realized it was not [inaudible]. There were some other things that come into somewhere along the line which I can't remember exactly where we'd-- where I think we found discrepancies and so on which we couldn't reconcile and so on. I think there were probably other [inaudible] but I can't remember now.

Sullivan: 24:53

Discrepancies between what and what.

Hazard: 24:54

Well, I think that between surveys and so on and things we couldn't find, something or other. I can't remember all of it. It's difficult to remember.

Sullivan: 25:05

Because there was a tremendous discrepancy between the 2C and the first installment of the Mills survey.

Hazard: 25:10

Well, that's right.

Sullivan: 25:10

[crosstalk]. That was the basic crux on the--

Hazard: 25:13

Yeah, I can't remember whether there was some other stuff we were doing ourselves with the interferometer as well. I can't remember.

Sullivan: 25:23

What do you think in retrospect-- I'd be interested in your opinion, was the resolution of it? Was it a matter that Mills basically had it right and the 2C was just confusion limited or do you think--

Hazard: 25:38

Well, the 2C was obviously wrong. I mean, I don't think it's--

Sullivan: 25:46

Do you think the P(D) analysis was useful at all or was that just a confusing issue?

Hazard: 25:52

Well, the P(D) analysis was interesting. I think the P(D) analysis was interesting and being-- I remember, we discussed the [inaudible] must be in the ripple in the background and I think that Scheuer, who did the first really good use of this type of thing which was the way that you obviously should go. And I think we probably all realized to some extent it was a little bit silly counting sources and then pinning them all and everything again [inaudible] you wouldn’t have to do it that sort of thing, if you knew how to do it properly. And so the P(D) analysis is I think was very important from that point of view, although I think that possibly it's,-- how [inaudible] would resolve the issue, it was an overestimated. And you could push it down a little bit deep but I think the [amount?] [inaudible] that you can really extend the whole thing much further than [inaudible] go very, very much deeper. I thought that was entirely [inaudible] deeper but you obviously couldn't go beyond the [inaudible]--and then what you really did [inaudible] sort of [inaudible]--

Sullivan: 27:05

And treating them statistically rather than knowing what source is where and--

Hazard: 27:09

Yeah. [inaudible] two or three times [inaudible] in a sense and so it was a much better sort of thing. But I suppose that it probably didn't at that particular time help to clarify the issue because it wasn't so direct as the source counts.

Sullivan: 27:24

That's what I was going to ask. Can you remember anyone or what's your impression of the fact-- was anyone convinced by P(D) that they should believe the results of the 2C and cosmology that came therefrom? Did it change anyone's opinion?

Hazard: 27:42

I don't think so. I mean, I wouldn't have thought so, but it was sufficiently clear cut until--

Sullivan: 27:48

Yeah. And yet the Cambridge group, of course, you and [inaudible] began to recognize that the 2C itself was unreliable. [Said?] now the P(D) is okay but what you're saying is that you think that the--

Hazard: 28:01

Well, I mean, I don't-- that's a thing I don't think that the-- yeah, but I'm sure that they go back on it. I mean the P(D)-- I think people recognized the power of that. All I'm saying is that I'm not quite sure whether it convinced-- it obviously didn't convince anybody. [inaudible] involved in the controversy. I think [inaudible] because, yeah, I mean I'm quite sometime after it and I think that they obviously--

Sullivan: 28:31

Why not? Why didn't they? You say that it was important in showing that this was a--

Hazard: 28:36

Well, I mean, I think that people wanted to find out what was really wrong with the 2C. I think it, obviously, was a pretty big [inaudible] to find out [inaudible] [theories?] and I think the question then of course-- so it certainly was true that the [inaudible] still happened at a very, very slope whether [he believed?] was all wrong, I mean, so the original claim on which the evolution [inaudible] believes was wrong. It was wrong. [inaudible] and now then of course, what they were doing is getting down to the much more difficulty thing, trying the things 1.5 and 1.6 something which is what the Australians have. In a certain sense actually, Mills did a very good analysis at that time because-- and I'm not sure whether he gets the full credit for what he did at that time because he did it the opposite way around. I think which was much-- [inaudible] I can't remember when he did this, because I didn't know he done it until long after, and I asked-- I think I asked why it hadn't been done this way. And what he did was he calculated, you see, what the effect on his [inaudible] would be from the confusion.

Hazard: 30:08

And to calculate that this is the [inaudible] slope of being faced. It was on the basis that I think that he calculated that the slope wouldn't be 1.5 it would be 1.6 or something and he was claiming that the things were consistent with the 1.5 thing. I mean, rather than other way around, which was yet an alternative method and a more direct method of doing it. So the thing itself wasn't all that bad, of course, in those days when it was giving us fairly strong [inaudible]. It wasn't all that bad for, from the-- and then the argument, of course, shifted.

Sullivan: 30:47

Why was 1.5 of any interest? I mean, after all, in a non-Newtonian universe, you don't expect 1.5. Or were there some people that thought that they might all be nearly relative?

Hazard: 30:59

No, whatever that it was. I mean, I can't remember what the--

Sullivan: 31:03

Because you wouldn't expect to say it didn't predict 1.5.

Hazard: 31:04

Well, there was in the beginning-- that's right. And I think that then you got into the argument afterwards. Of course, the arguments shifted slightly, but although the slope was nearly 1.5-- well, I'll come back to this. Although the slope nearly was 1.5, it shouldn't have been. That was then the argument. Of course, it should have been wildly different from 1.5. And then I think some people probably started to get a little bit uneasy because it's an, unfortunately it's a problem that’s cropped up in a lot of cosmological investigations over the years. But if you adopt a statically Euclidian theme, many of us ask, could it much better [inaudible] in universes. It's the same with angular size relationship. It's the same as the [inaudible]. If you were shown this type of Euclidian, then the probability comes out. Obviously, you aren't coming out of that 0.5, which is what you expect. And I think people got a little bit worried.

Sullivan: 31:57

Kellermann has a lecture in which he pointed this out rather nicely. I don’t know if [inaudible] you remember that .

Hazard: 32:03

No. Well, I mean, this worries people all the time, I think. This was a sort of--

Sullivan: 32:06

At that time, I don't remember this question being discussed, but really, a 1.5 always seem to be the standard that people are comparing against, but no one ever says, "Well, in fact, you never do really expect 1.5 in any kind of modern cosmology."

Hazard: 32:21

Well, I tend to do-- I mean, they were. I think that once you start to-- by the end of the 1950s, 1960, surely around when I think they--

Sullivan: 32:34

By the end of when?

Hazard: 32:35

In the early 1960s. But Ryle and them were pointing this out when they're comparing--

Sullivan: 32:39

Well, I'm thinking more of late '50s where they were saying it's much different from 1.5.

Hazard: 32:48

Well, what does it say-- well, of course, at that time, I think one wasn't taking into account very much the cosmological effects because usually you know how far away these things were. But I think--

Sullivan: 32:57

Yeah, that’s what I’m getting at.

Hazard: 32:59

I think that they were [short distances?], and I think probably the very bright ones wasn't-- I mean--

Sullivan: 33:05

But you needed to, of course.

Hazard: 33:07

We needed to. Well, I think that in all of astronomy, in all of these things, one has to be a little bit careful in assessing how arguments go, you know what I mean? You're given an impression you get if you [read the things?] that there's a whole sort of controversy going on involving everybody. And, of course, that isn't the way it happens. What actually happens is that you have merely two groups involved and a couple of people that are spokesmen for it, and most of the people just sit and listen. I mean, you saw it. I mean, [inaudible] one of the interactions I got through somebody. [Paris?] that gave that talk. It must have been [inaudible]. [Who could believe I nearly said all this stuff?]? And so we're all listening again just because Ryle knows what he's doing and so on. And that's the attitude of a lot of the people in the whole game that they listen to one or two people who are actually conducting the argument. Everybody isn't in the argument because everybody doesn't have all the data. So everybody who's not actually doing number counts isn't particularly worrying about whether you've put in the various cosmological [inaudible] which they would do perhaps if they sat down and start to do the number counts. It’s the thing I've always found when I started to tackle the problem.  You can find all kinds of faults in the analysis beforehand.  But when you [inaudible] do it.

Hazard: 34:31

So people are sitting here and instead of-- some people in one camp and some in the other, but most people just sitting, watching the argument develop between two groups. And they themselves weren't terribly worried and I'm sure that people who were involved in cosmology would've probably [inaudible]. But the argument developed into something different. The argument really didn't develop, you see, to some extent for a long time as to whether or not what particular cosmology we're in or whether in fact, what your interest was-- is it consistent with some particular model? But the argument soon developed and the fact that you have two surveys which didn't agree at all anyhow. They have completely different results.

Sullivan: 35:16

The two things got mixed up.

Hazard: 35:18

The two things got mixed up and I think that's the worst thing [inaudible].

Sullivan: 35:23

And of course, the steady-state was particularly prone to attack because it didn't make a specific prediction which could be tested.

Hazard: 35:31

That particular form--

Sullivan: 35:33

Although there were two forms of it and I’m not sure that was typically appreciated by some of the--

Hazard: 35:38

I think there was a mistake and I've said that too.

Sullivan: 35:42

[That's amazing?].

Hazard: 35:43

I think the [state has?] gone to steady-state, and I don't believe that really was the argument. The argument really was where it was Creation or not, the Big Bang or not. And I think in that particular-- if you switch to that particular form of the model, [inaudible] settled yet.

Sullivan: 36:06

Now why do you say, going back to the '50s, that that was really the [crosstalk]?

Hazard: 36:11

[inaudible] Why do I say that? Well, I asked [Gold?] once [inaudible] why this [inaudible] because in fact [inaudible] in the beginning. That wasn't a necessity in the continuous creation model.

Sullivan: 36:29

That would be homogeneous.

Hazard: 36:30

That would be homogeneous and he said, "Consult with the best experts of the time." [inaudible]. The universe was homogeneous and isotropic, and I think one of the first things you learn about the universe is exactly not that. [inaudible] by saying it was on the sort of scale of a Hubble radius [inaudible] was fixed and so on. They hadn't made that assumption. They could have had all kinds of models within the same context. Well, I don't know. I believe that there were personalities involved in all that, that must be very difficult to-- I don't know what was going on here at Cambridge at the time, but there obviously were personalities going on, which [inaudible] problems get resolved because they were [inaudible] change everything. I think that the--  Why-- because I think that those things happen which we don't understand ourselves-- I think [inaudible] things possibly were behind Big Bang model and continuous creation. And some people didn't like the idea of continuous creation for some reason or another.

Sullivan: 37:58

The predilection's really more philosophical or--

Hazard: 38:03

I think philosophical and so on. I think the whole idea of the steady-state seems philosophical in a certain sense. But obviously [inaudible] why people don't like this continuous is again philosophical. But I'm sure of it. If you read the writing, and Lovell, and [inaudible]. This is everything about philosophical educations, and various things and so on. As to how they react-- I don't see it that way, myself. But--

Sullivan: 38:40

You would say that the participants in this thing were not giving much weigh, or that kind of thing having much influence on their arguments?

Hazard: 38:51

I think it probably had a bigger influence than they would know.

Sullivan: 38:55

Yeah.

Hazard: 38:55

I'm sure with you. But I think there was a lot-- I think there was distorted here by personality probably.

Sullivan: 39:03

Yeah, sure.

Hazard: 39:06

But see, I would say it’s a tremendous role in the way in which radio astronomy developed in Cambridge. Because the development of a lot of the instrumentation and the way [inaudible] went, where in fact, geared to cosmology.

Sullivan: 39:23

Right. The source counts.

Hazard: 39:24

The source counts and so on. And so they had a very strong positive impact in the development of new techniques. But I think this may be one of the ways where perhaps the whole study got distorted and the emphasis started on what's there. I'm not putting it too unkindly, I tell the [inaudible], "Oh, [you're holding so far?]." I tell you one other thing, actually. Many of us, I think, were the [inaudible] that by counting 25 sources or 50 sources and so on and you could solve the structure of the universe. So there were some of us having clearer [inaudible] view about the whole operation anyhow. On the data that was available at that time.

Sullivan: 40:12

Most of the [inaudible], so much of it was based on that.

Hazard: 40:15

That's right. I mean, I think-- I still find that you can [inaudible] pieces of wire together. Count 50 sources and say, well, we sold everything, you know, I think, and I think some people thought it was a bit simplistic. I think, to think about it was as simple as that.

Sullivan: 40:31

Well, but are you saying, if you stick a few pieces of wire together and count 10,000 sources that might be able to do it?

Hazard: 40:36

Well, I think when you solve it, I think that. It all seems a bit too-- Yeah.

Sullivan: 40:41

So you're saying that really investigating cosmology scientifically may be a bit naive.

Hazard: 40:47

Well, it's obviously a bit naive when we, in a certain extent when we don't know what we're dealing with a lot, it's obviously, you know, that when you're looking for what a fairly subtle effects and so on, and I think this has being born out in many cases, I think you, you find deviations and various things occurring in the data. And I think that you have to be a little bit careful in interpreting these particular cosmological effects when you don't really understand the physics of the objects and all kinds of other things going on. I think we all want to solve the cosmological [inaudible].

Sullivan: 41:27

Now we've been talking about cosmology specifically and talking about some quote-unquote non-scientific elements that enter into it. Is this true of the rest of astronomy or radio astronomy also? Or is it really come out to only in cosmology?

Hazard: 41:46

I think it comes out mainly in cosmology, but I think that to some extent the-- a lot of the rest of the work is connected. I think it comes out. Oh, no, there are certain non-scientific things come out in any science. I think, I think, no, I think we, I said require, I think that the idea that you have a, you know, the whole scientific community been involved in argument, isn't in fact true, which it's usually the argument occurs in two polarized camps.

Sullivan: 42:21

And so the idea of checks, you mean?

Hazard: 42:22

Well, I think the idea that I think the idea personally, myself and the, that the idea that science is some objective [inaudible] is just lot nonsense. I mean that I think maybe science is, but that isn't the way science, science is done in that way. And I doubt it would get done in that way. What? It depends. Some people in general taking up some extreme position and [there maybe holding fields?] for quite a long time. Cause it might be the most person,

Sullivan: 42:49

most most influential [inaudible]--

Hazard: 42:51

That's right. And then, then somebody else. Will take it. And most people, you know, I haven't spent enough time in various disciplines and to be able to really take a, a very firm role in it now. And if it's on some peripheral thing, then of course nobody ever does. And it's only, I think, over a long period of time, averaged all the time and averaged all of people that you get this objective thing in the end that. But so I think that and the science can obviously go wrong quite dramatically official period.

Hazard: 43:27

Because of this thing, depends on who gets the money, who gets to say how influential they are.

Sullivan: 43:33

The checks of experimental results doesn't work because it is just so much effort that only a few people actually,

Hazard: 43:40

Probably a few people actually ever involved in, in the particular investigation. I think that's the thing there, you know, there's a lot of money involved, lot of time involved. And so I think that they, it's a relatively small number of people involved actually in tackling a particular problem at any particular time. And they say, and I think possibly they all agreed. Maybe this argument we were seeing in the 1950s is very healthy state of the affairs, because if everybody had agreed--

Sullivan: 44:08

Yeah, sure.

Hazard: 44:08

With some of the items we might have gone in even more wrong at that time.

Sullivan: 44:12

Yeah. Yeah.

Hazard: 44:14

But that, so there is personality plays a role, and then I think, cosmology, is particularly prone for obvious reasons. I think it gets down to the root problem. And at the present time, I think it's very difficult to figure things out. But I think we get back to something you want to talk these extraterrestrial stuff. I mean, I'm very interested well, in a certain way as to why people are interested in this.

Sullivan: 00:00

Interview with Cyril Hazard on 3rd June, 1981. So you were saying that--

Hazard: 00:05

Well, perhaps you can answer the question for me. I mean--

Sullivan: 00:08

Well, let's finish your thought as to why you think that people are interested in the search for extraterrestrial intelligence.

Hazard: 00:13

Yeah. I was saying perhaps you can tell me what I want to know. I mean, I strongly suspect that some of the people involved are seeking a replacement for a type of religion which they've lost. I mean, I can see, I think, that a person brought up in a fundamentalist-type religion who had the roots cut out from under them by studying science might, in a sense, then seek a replacement. And I do notice this tendency in many of them, to be seeking help from extraterrestrial beings. And so then I wonder whether that's what attracts some of them.

Sullivan: 00:49

Well, I agree with you. There is a certain few who have said this, and probably more who haven't, where they are seeking answers from above in a similar sense to the medieval concept. Personally, I'm very interested in just establishing the contact and I think it's going to be tremendously difficult to get any information. So that's my motivation. But I agree with you. There is a concept to that but we can talk more about that later. I'd like to.

Hazard: 01:17

That's right. That's right. But what I'm saying is science is involved in all of these type of things. I mean, I'm not particularly interested in it because I don't think I have any particular hang-ups in that direction and--

Sullivan: 01:29

But you don't have to have religious hang-ups to be interested in SETI.

Hazard: 01:30

No. I know you don't. But I mean, no. No, I know you don't. I know you don't. But I mean, I'm saying that is one of the things that get people involved in it and you don't know what your own motivations are.

Sullivan: 01:48

Oh, of course not. I mean, I can say what I think they were. Let me go back to a couple other meetings at Jodrell Bank. In '53 and in '55 there were two meetings on radio astronomy and I was wondering if you had any recollections of those [inaudible].

Hazard: 02:02

Which ones are those? '50--

Sullivan: 02:03

'53 was the one where you presented your thesis results.

Hazard: 02:06

I don't think I go to '55.

Sullivan: 02:08

Maybe you didn't go to that one. That was before the Dublin IAU meeting.

Hazard: 02:11

Yes. I didn't go to that one.

Sullivan: 02:13

What do you remember about that '53 meeting? It really was the first meeting, I think, that had radio astronomy as its title, so to speak.

Hazard: 02:19

Not a great deal. I had [inaudible].

Sullivan: 02:23

It didn't influence you greatly in terms of--

Hazard: 02:25

It's difficult to say. I mean, I remember that [inaudible] was there. I think Minkowski was there. And I think that might be the first time I met him.

Sullivan: 02:42

But it didn't lead you in different directions as far as you can remember?

Hazard: 02:45

No. Because again, it came at an end of a period for me when that sort of work was being wound up and I was leaving anyhow.

Sullivan: 03:00

Well, how soon did you leave after you got your degree? I thought you still had another year or two.

Hazard: 03:05

No, no. I went back. I had in fact-- I went back to finish up some papers for six months with Hanbury Brown. We just spent the time writing papers.

Sullivan: 03:19

So you left shortly after you got the degree, and then you came back for six months?

Hazard: 03:24

Yes, you had to leave pretty well after you got the degrees here, because we had to go on national service before we were 26 or something. But I think I'd never heard anything from them, so I thought I better do something about it. They called me up, about a week to go. [crosstalk].

Sullivan: 03:42

Okay. Now, the final questions have to do with the occultation business, and 3C 273. Now, we talked about this at length, but there are some things I just wanted to clear up. First of all, when you worked out the basic principles of how to interpret an occultation record, did you have anything to go on in the optical astronomy literature?

Hazard: 04:11

Nothing to go on at all.

Sullivan: 04:12

So people had--

Hazard: 04:13

I knew nothing about it at all.

Sullivan: 04:15

Right. But people had not done the kind of photometry that optical astronomers do today with stellar occultations and--

Hazard: 04:20

I don't know. I mean, they may have done, but--

Sullivan: 04:23

I see. But it didn't impact on you at all, no?

Hazard: 04:24

I didn't know anything about it. Yeah. It cropped up, I'm sure, in some conversation when we were talking, J.G. Davies and myself, over lunch we've had most of these things did. And I can remember, I sort of worked out that we could get positions and structures or information structures to a second or so of arc. And I remember I wrote a report to Lovell at the time saying that-- I know exactly what I said in it. It must be in the record at Jodrell somewhere. I'm asking for time on the-- this was about 1957. I'm asking for time on the 250 foot to do this because I reckoned that I could identify some of the Type 2 sources. It was really a follow-up from [the thing I began?]. And I said if we even identified two or three of these it'll be well worth our project. Because the only way that you're going to be able to compete with the [inaudible] thing is to build telescopes a mile or so across, and of course nobody's going to do that. Well, of course, they did, but, I mean, at that time, I didn't think they would do. And so the problem by then was very specific. So, again, you see the shift in the emphasis of the work, of course, because now the thing is getting much more strongly focused on the problems, I think. And the idea was, I knew you could identify the sources, and you have to identify one or two of them.

Sullivan: 06:03

Well, now, you published a paper on 3C 212 done with--

Hazard: 06:08

That’s right.

Sullivan: 06:09

-- the big dish. But in that paper, it says that many others have been observed. And--

Hazard: 06:13

That's why I--

Sullivan: 06:13

--I'm going to write that up, and I don't think that ever happened.

Hazard: 06:14

I never did because what happened, I think, was that-- and I still got all the records, I meant to do it, in fact, on one night, the same night 212, and then there were four occultations. And one of those nights I thought that the incident had gone wrong. And it was only afterwards I realized that what had happened was that there were four occultations, and several of them were double.

Sullivan: 06:38

Within a short period.

Hazard: 06:39

[crosstalk] now, so what you had was sort of 16 steps on the record over a relatively short period, and the whole thing looked a mess. You see, you have to remember the analysis. We have no active positions to locate anything. So small steps on the record. You didn't have the digital type analysis. And what I think actually happened was I must put all this stuff together [inaudible] some interest still, and I have all this data, was that I started to get the technique was developing, and by this time, by the time I got to that stage, we got onto 273. And then the occultation stuff was developing at Parkes. And we're getting much better records by this time because by this time we were able to keep the occultation by this time.

Sullivan: 07:22

So the others sort of got shoved to the side.

Hazard: 07:24

The others got shoved to one side.

Sullivan: 07:25

But now, you weren't on the 273 while still at Jodrell, were you?

Hazard: 07:28

No, no, no, no. But what I did in 212, you see, I wrote that up in Australia.

Sullivan: 07:35

I see. It was even after you’d gone to Australia?

Hazard: 07:37

Exactly. Gone to Australia. So I worked up then, and what happened with 273 was the situation was just starting to change at that time. Prior to that, we tried to do some-- or I tried to do some-- predicted occultation, and they always failed because the position was always miles out. And they're also relatively weak sources. Now, the interesting about 273, was it was one of the strongest sources in the sky. Its position was known pretty accurately.

Sullivan: 08:15

So you're saying that the positions are so inaccurate that the time of occultation was off by--

Hazard: 08:20

Didn't even get a [inaudible].

Sullivan: 08:21

Didn't even a [inaudible], it was that bad.

Hazard: 08:22

That's right, that's right. And [inaudible] miles off [inaudible], so that you couldn't really use them as [inaudible]. So what we usually found was [inaudible].

Sullivan: 08:32

So you had to have at least a five-minute accuracy position to have much--

Hazard: 08:35

You really need better than that because five minutes still gives you a good chance of missing it when you do it. I mean--

Sullivan: 08:43

Usually, it's not going to the center [crosstalk].

Hazard: 08:44

That's right, [crosstalk]. That's right. [inaudible].

Sullivan: 08:47

Okay. But 3C 273 was strong, therefore had a decent position.

Hazard: 08:51

Yeah, it had a decent position and therefore pretty certain that it was going to get occultated. And what happened was that I went down to Parkes on the first occultation, which was about April.

Sullivan: 09:03

April what year?

Hazard: 09:04

'63 or '62 I think. '62 I think it must have been.

Sullivan: 09:10

I think that's right. I can check that.

Hazard: 09:11

[crosstalk]. And that particular time, we're just going to get the [emersion?] just as it was disappearing from the field of view of the telescope. That was right. And that was all we could get. And it was only barely caught within two or three minutes. So we just got the record and you could see the diffraction [load light?]. And therefore we knew next time to really go for it because again, you see, there was nothing known about 273.

Sullivan: 09:45

It was just a bright source.

Hazard: 09:46

It was just a bright source. There was no interest in itself. The real interest in it was that this first shot at it, which was only a minute to go at it, had shown the diffraction [loads?]. So there was a strong start like that. It was obviously going to get really good diffraction patterns and that the system could really work. And that was the real motivation for it.

Sullivan: 10:14

You mentioned something in a previous interview that Minkowski was in Australia--

Hazard: 10:19

Minkowski was in Australia [crosstalk].

Sullivan: 10:20

--and had a plate of 3C 273. So you could make the identification.

Hazard: 10:25

We didn't really make the identification. I think we should put this because [inaudible] has written something which isn't right either on something from the Cardiff thing. What actually happened was this. When I took it back, there was no method then of analyzing stuff digitally or so on. I think that [inaudible] made some [inaudible] completely wrong because what I wanted to do was to get a really active position and get really good structures out of the whole thing. And this was a pretty long job by the time you put all the occultations together. It's not as simple as some people think because you got the thing and next week you put it into print, because this hadn't been done before. And I had to construct models [crosstalk]--

Sullivan: 11:11

When you said there's no digital--

Hazard: 11:14

The digital stuff was just coming into operation--

Sullivan: 11:15

What you meant was that you had strip chart recordings which you laboriously had to--

Hazard: 11:18

That's right--

Sullivan: 11:19

Would you digitize them by hand, essentially, or?

Hazard: 11:21

Well, I didn't quite get it that way because there was no need to.

Sullivan: 11:27

Did you lay down templates of what different patterns [inaudible]?

Hazard: 11:30

What I had to do was to work out what all the patterns would be. I still got them somewhere, but different sources of different angular sizes, double sources and everything. So I spent a load of time working out all the diffraction patterns and all various types of diffraction patterns. And then what I had to do was to construct the diffraction patterns which would match these particular ones which we had. Now, one of them was fairly easy because the two sources were well-separated, but the others, the way they were merged, took quite a bit of time to construct this and get them to fit to the accuracy that I wanted.

Sullivan: 12:03

And did you really do this sort of on tracing paper to weigh them down?

Hazard: 12:05

Graph paper.

Sullivan: 12:07

[inaudible].

Hazard: 12:10

And then I worked out the positions by working out from the positions of the lobes back to the straight edge thing so you could work out up from each lobe, each maximum [inaudible] to work out where the edge was. And so this was a long laborious job. And then again sent those positions to [Herstmonceux?], who then provided a source position because now you're getting into the region again, which I think that Hoyle misinterprets.  I mean, first of all--

Sullivan: 12:47

What does Hoyle say, first of all?

Hazard: 12:48

Well, he implies that John Bolton got involved in all this and that I wouldn't have published it quickly if he hadn't-- all kinds of odd things. He misses the point. This was along from the October thing. The thing was published in April or something. It was all this analysis to do and then that he sent it off to Schmidt. Now, the reason he sent it off to Schmidt was he asked me [inaudible] he could send it to Schmidt the position.

Sullivan: 13:15

Bolton asked you?

Hazard: 13:16

Bolton, yeah. And the reason why he did and I hadn't done it was—because I wouldn't have done it if I had known a lot of the stuff now that I know about thing-- because he was one of the few radio astronomers who knew any optical astronomers. I didn't know any optical astronomers. And the other point is that I'd never been involved in identification work before. But it was after that I learned it.

Sullivan: 13:46

Well, you had to some extent but--

Hazard: 13:48

Not at this sort of level. Second of arc, [inaudible] never used the sky to survey things looking for faint objects and so on. Now, what happened anyhow. That's a separate point. So this was a new thing where it meant learning lots of new things and the spectroscopy, I hadn't learned anything. But the idea had always been to identify these things. Now, what actually happened was that Minkowski was at CSIRO when I got the first position and I was continually finding this position for quite some time. But we got a first position, now I can't remember how I got in one of the [inaudible] program to work out of this. I can't remember [inaudible] but anyhow we had first position. And we probably actually had it from the predictions where they gave the angle of cuts and so on and we just displaced it across and got a position at that stage. We should probably say [inaudible]. And I was in the corridor over at CSIRO, which was in the Sydney University grounds in those days, and Bolton [inaudible] that was another thing where to [inaudible]. But he says Bolton asked me to continue. Actually, it was Pawsey, [inaudible] wanted me to do occultation work at Parkes and I gave a talk about it. Now, I mean, Minkowski said [inaudible] he said, "Well, I've got finding [chart?] [inaudible]."

Sullivan: 15:40

So it wasn't a plate, actually, just a print?

Hazard: 15:42

It wasn’t a plate, just a print. And he said, "Well, it's been identified with this galaxy." And this was over to one side [inaudible] but obviously we were miles away from this position, a minute or so of arc away, at least. And when just [inaudible] this position, you could see it landed right where this bright star was. But we didn't [inaudible] obviously there's nothing unusual with [inaudible]. But you could see the jet streams coming away [inaudible].

Sullivan: 16:11

You could even on this thing [inaudible].

Hazard: 16:12

Yeah, that's the whole point. You could see the jets coming away. And it was obviously in that region between, roundabout the star and this jet thing. And I remember him saying, "Well, it looks as though this is an edge on galaxy. And if this is the case, then this will be the first edge on galaxy that's ever been identified with the radio source." And that was as far as that went at the moment.

Sullivan: 16:32

I see.

Hazard: 16:32

And then what happened was the position was sent to Schmidt. Now, of course-- Nowadays, of course, if I've been involved in the [inaudible] then you just come down and done all the identification work itself and finish it up yourself. And now we just got in a couple of minutes. But in those days, you sent [inaudible] you can identify the position like you said [inaudible] second of arc. And then Schmidt could see what the arrangement was with the jet and the star and took the spectrum. Then the whole thing is murky because people tried to rewrite history of this day.

Sullivan: 17:09

Well, hold on, Minkowski so never did follow this up himself?

Hazard: 17:12

No.

Sullivan: 17:14

Okay. But Schmidt having gotten this position--

Hazard: 17:18

Checked on it [inaudible].

Sullivan: 17:21

--also found this star independently really of Minkowski.

Hazard: 17:25

Yeah. Well, there was nothing [inaudible].

Sullivan: 17:31

But now, what are you referring to as far as history has been [inaudible] from then on?

Hazard: 17:35

[inaudible] I think that what actually happened then was that the fact that once 273 was identified, obviously the crucial point there that was [inaudible] low redshift and had the Balmer series. I mean, in retrospect, that's the crucial point about it. And this enabled 3C 48 to be immediately interpreted, which was then published in the same thing following on, which wouldn't normally be done, of course, because [inaudible] Greenstein happened to be down the same corridor as Schmidt. I mean, that normally wouldn't have happened. Several months later on [inaudible] would have come up with different interpretations. And then of course, I think these things to what you then claim as a discovery of a thing as to what is a discovery because--

Sullivan: 18:23

Exactly.

Hazard: 18:23

--you can then go back and twist everything. But as far as I can see, the only reference to 3C 48, possibly an extragalactic, is that it probably wasn't extragalactic or whatever it was. So that was in Sky and Telescope. I have the history thing down here, I got some of [inaudible].

Sullivan: 18:46

In the AAS talk that's reported in the Sky & Telescope?

Hazard: 18:50

Yeah, but you don't count that, I mean, and what it say, there is more possibilities, a very distant galaxy of stars, but there is general agreement among the astronomers' concerns. There is a relatively nearby star with the most peculiar properties. And that's the Sky and Telescope report.

Sullivan: 19:08

That's 3C 48.

Hazard: 19:09

That's 3C 48. Now, how you can claim on that basis-- I mean, but anyhow. But I think that the crucial point to remember here is that, in fact, what people don't realize is the amount of work that went into the occultation part of it. They've obviously taken off, and you've got a radio position. And people seem to think now in some cases that 273 was a quasar which was investigated by radio techniques. But this was the first time that the real-- I mean, I've done a lot of this stuff already, some of the stuff, obviously, plus 3C 212. I mean, 212 is better as well. And the people [crosstalk]--

Sullivan: 19:48

What is itss redshift, per se?

Hazard: 19:49

Quite honestly, it's much higher. That's what it is. It's quite a high rate here, much [crosstalk]--

Sullivan: 19:55

Don't worry, Cyril. I'll get it right.

Hazard: 19:57

That's all right. No. You know what I mean? All these things get twisted, I mean, because the point is you can't buy history.

Sullivan: 20:03

Well, you can try.

Hazard: 20:04

But you can try. But I mean, it's difficult to--

Sullivan: 20:07

But you do get into questions of what is history, and what is the discovery, and all these, of course, some of the things that--

Hazard: 20:11

Well, I mean, when you write a paper that-- the way you write the paper is not the way you did it--

Sullivan: 20:18

Exactly. That's--

Hazard: 20:19

--because you did it the way you did it. Nobody ever understands why [crosstalk] you [crosstalk].

Sullivan: 20:21

But that's precisely why I'm doing some of this and not just reading the papers.

Hazard: 20:25

That's right. That's right.

Sullivan: 20:27

Okay, let's move on here. Before now, we discussed at some length your objection to the idea that the discovery of quasars was a natural consequence of the long baseline interferometry done at Jodrell.

Hazard: 20:42

That's right.

Sullivan: 20:43

And I just want to make sure that I had--

Hazard: 20:43

Now, when you think about the--

Sullivan: 20:45

I just want to make sure I had that straight.

Hazard: 20:47

Yes. It's nothing to do with this.

Sullivan: 20:50

I mean, because you were at Jodrell, but you were working parallel and independently of this.

Hazard: 20:55

Completely independently of that. And I think that [inaudible] and Palmer-- I mean, the other exciting thing in this is Henry Palmer. And if you read his book, which I think I've given to somebody. Have you ever seen that book, [inaudible]and Palmer book? It came out probably about that time.

Sullivan: 21:11

Oh, yes, the 1960 book.

Hazard: 21:14

That's right. Well, if you read-- well, it must be '64 or something. That's when they discovered quasars.

Sullivan: 21:20

Well, I'm not sure I know which book. But--

Hazard: 21:21

Well, and that's probably as I--

Sullivan: 21:24

So in this book by [inaudible, Carr?] and Palmer, which is around '64 or so.

Hazard: 21:27

Well, what Palmer says is before this stuff would come to fruition, the whole thing was overtaken by the occultation work. And he goes into some detail. And that's exactly what happened. It's the normal sort of thing. This was coming in from a different angle of attack which jumped the whole game. Now, when I wrote this stuff up in the first Texas Symposium-- and I've put a lot of stuff in about the Jodrell Bank stuff. But as a matter of fact, I read that afterwards and put it together in the normal way in which you write a scientific paper and put all this sort of stuff in some sort of--

Sullivan: 22:05

Giving credit to previous work and--

Hazard: 22:06

--previous work and so on. But it really had nothing to do with it. Only in the sense—of course, this is anticipating but this work was started by 1957, is that we knew that the [occultation?] was to get small angular scale structure and so on. So we knew that we wanted to get down to measure angular sizes and so on.

Sullivan: 22:30

But now, what was it that directed your attention to small angular sizes as being of interest?

Hazard: 22:36

I don't think it was small angular sizes as such as the--

Sullivan: 22:40

Is the accurate position. But I knew--

Hazard: 22:41

--[inaudible].

Sullivan: 22:42

So it's the identification problem.

Hazard: 22:43

But I knew you could get the angular sizes out of it as well, I mean, because it was in the-- so it would be 1957 when I started doing this. So there wasn't a great deal done then, but we already knew these things was fairly small.

Sullivan: 22:56

Well, from what would that be? Just from the [Jennison?]--?

Hazard: 23:01

The [Jennison?] sort of stuff and so on, I think, yes.

Sullivan: 23:03

Only for a couple sources, really, though.

Hazard: 23:05

That's right. There wasn't a great deal of no, but--

Sullivan: 23:08

But what do you think is the importance of the Palmer, Morris, and Thompson work in the late '50s with the long baseline interferometer?

Hazard: 23:18

Oh, I think that they were pointing towards the direction of a very small angular scale of structures and so on of all these sources. I'm not saying anything at all except that that work had nothing to do with what I did on 273, that was all. And I'd never heard-- at least I don't think I'd ever heard of 3C 40. I think I may have heard-- see, I was working on the intensity interferometer and not doing radio astronomy at the time. I was only doing this every month or two, doing an odd day at Parkes, so I actually wasn't doing anything at the time. And it certainly was never discussed with John Bolton in any sense that these sources were important, and I think I might have heard roughly that there was some sort of [inaudible] with radio stars, but everybody thought, well, that's all right. [inaudible] want to identify with radio stars sometime, and I don't think anybody that I knew was particularly interested. And in fact, the whole thing comes out-- the fact that the whole thing started as soon as these papers were published on 273. I mean, then the interest was [inaudible]. Before that, there was no general discussion in the literature. What the importance of it? Oh, I think it was the first big sort of surveys on large scale and angular structures and so on, which would develop--

Sullivan: 24:42

The Palmer and large scale--?

Hazard: 24:43

That's right [inaudible]. I mean, it's very difficult to look back and say what was the importance of it because in the long term, nothing has any importance. I mean, if you look back and say what was the importance of this stuff that we need on M31 and so on, it's of no importance at all nowadays. I mean, because--

Sullivan: 25:03

Well, yes and no. That's something we can discuss but--

Hazard: 25:05

Yeah, but all I'm saying is I think that--

Sullivan: 25:09

You mean it's been buried by so many more recent--?

Hazard: 25:11

It gets buried by so many more recent stuff that it's difficult to say, well, it's difficult to be sure it’s this, that, or the other because it was the first steps in what was a very important investigation, and they got some very interesting results, I think. I mean, the first step was the [inaudible] of the broad sources in the galactic plane, which then led, I think, to the recognition that you did have these small sources and, again, it's part of the whole picture now with what you-- again, although you said they were talking about, if you look in the early papers, cosmological effects, because the angular size shouldn't be less than one point something seconds of arc and so on, things like that, which in itself now one doesn't take too much notice of. But again, it was the stuff that was leading to the idea, really, that the nucleus of the galaxy was the big thing, again. So we were playing in the dark here, and it was only later on when you go back and look at some of the stuff, that you can fit it all in and see what it was all about.

Sullivan: 26:10

Well, right. Okay, a couple of last question. You went down to Australia to work in Narrabri. You were hired by Hanbury, essentially.

Hazard: 26:17

That's right.

Sullivan: 26:20

And the thing at Parkes was a sideline.

Hazard: 26:22

Yeah, I gave a talk in the physics department on occultation with the radio [inaudible] then Pawsey asked me to go and continue to work at Parkes.

Sullivan: 26:31

I see. So you weren't actually-- you didn't go and say I'd like to do this at Parkes. It was actually Pawsey that suggested that you--

Hazard: 26:38

Well, I mean, I think I probably had the idea. I can't remember, but I gave this talk when I got down and Pawsey was very interested and offered me the facilities, but you got to remember there were other problems there. The physics department in Sydney wasn't on good terms with CSIRO.

Sullivan: 26:53

And you were part of that because you were connected with Hanbury.

Hazard: 26:55

Well, I was connected with Hanbury to some extent. I was in a more favored position because Taffy Bowen was Hanbury's best friend. And the trouble with Mills. And Christiansen, that's right and [Bowen?] and so I don't know all these [inaudible], but it was pretty bad. So I was a bit caught in the middle here.

Sullivan: 27:18

Yeah, [inaudible]

Hazard: 27:19

I had no problems at all.

Sullivan: 27:23

Right, but when you went down to Australia, you didn't go down with the idea I'll do some occultations at Parkes. This only really came up after you got down there.

Hazard: 27:31

I think that came after I got down there. And I think that the other thing is there was another problem which people don't realize is I gave the, I think the paper to Baldwin. I gave it to send in, I don't know how it got sent in, but to Nature, and there was a bit of thing obviously I'm suggesting all those things is published together and so on, and it came out with the CSIRO address on it which didn't do me any good. That was a bad mistake.

Sullivan: 28:14

I would be interested since you were an outsider coming in more or less neutrally, although you were associated once you got there with Sydney University as to what you saw as the major sources of conflict between Christiansen, Mills, Pawsey, and--

Hazard: 28:36

I never saw any sources of conflict there.

Sullivan: 28:38

So you only saw the aftermath of it are you saying?

Hazard: 28:40

The conflict was with different personalities that I saw. I saw a different conflict you see.

Sullivan: 28:50

What did you see?

Hazard: 28:52

The argument went on between Bowen and [Harry Messel?] that was the main problem.

Sullivan: 28:58

Did he feel that [Messel?] had stolen--

Hazard: 29:00

I don't know what the whole thing was. I mean, I suppose there were problems, I think, that were connected with Mills. And I don't think Pawsey-- I think Pawsey was in the same—certainly the conflict wasn’t Mills and Pawsey. That wasn't the case. The argument I think goes back, obviously there was some situation of jockeying for power inside CSIRO. There was a lot of people there.

Sullivan: 29:34

300 people.

Hazard: 29:35

That's right. So I don't know the ins and outs but as far as the bits of stuff that I gathered was that one of the things that did happen was that Mills and Pawsey and Christiansen didn't want 210-foot built as far as I know. At least I'm assuming Mills was probably pushing his own ideas, and I think that Pawsey was involved and they wanted to keep this [inaudible] tradition of Australian radio astronomy which [inaudible] innovation to tackle problems. And they thought that in retrospect they were probably right to some extent, but that's the way everything goes. I also think--

Sullivan: 30:23

They needed to have this big single telescope, rather than small groups that were out in the field.

Hazard: 30:29

And once the decision was made, there was no room for Mills in the organization. I mean, if he wanted to build a Mills cross, he had to do it somewhere else. So obviously-- I also think that there was questioning, and I think Pawsey was involved in this. Now, you have to check this with somebody more closely involved. But as far as I remember, there was a move to try and get [to the astronomy thing?] and transfer it to the National University. and I got a feeling that Pawsey was involved in this and I-- this is a vague recollection, and probably Christiansen and Mill's involved in this. And if that's true, then that's where the real trouble stems from. That's where the real trouble stems.

Sullivan: 31:09

Bowen would resist this [crosstalk].

Hazard: 31:11

If that's true, then that's probably the real source of the problem. And then with Mills and Christiansen going to university, Mills in particular, going into the Physics Department, then I think [crosstalk].

Sullivan: 31:29

Okay, but let me ask about your impression of Radiophysics, not these personality problems, but you came down there and you obviously had known about them for a long time, but now you could actually see them in operation. Can you just give me your overall impression of their work and their style of operation and so forth?

Hazard: 31:46

Well, I wasn't all that closely involved with them as such because, see, I saw them mainly in Sydney.

Sullivan: 31:58

Not out of the site?

Hazard: 31:59

Not out of the site.

Sullivan: 32:00

I see.

Hazard: 32:01

And it was only when I went out to the site to do the observing. I worked with a Brian Matthew. He was very good. And John [Shiman?] got involved and that's because he built the telescope. But, I mean, [inaudible] he had his own work, essentially. But Brian Matthew didn't upload the stuff later on as well, because in the whole setting up of the observations, and so on, he left radio astronomy as well. So I was involved with them and with John Bolton. I remember that it was a very efficient operation out at Parkes. I mean, it was a very good telescope. The organization of Parkes was good. I knew most people there, so it was a nice place to be out at. And they were all very helpful, and technically, they were very, very competent, probably one of the most technically competent sort of places and efficiently run places you could come across.

Sullivan: 32:59

But you didn't have much chance to see the non-Parkes aspect of Radiophysics?

Hazard: 33:05

I only saw the-- I didn't see anything of the rest of it at all. I used to go out and see the survey. I had the survey—[some of the survey being done?] some of the survey work and just the scanning across bits of the sky [crosstalk]. But otherwise, I saw nothing apart from that, except when I sort of, "Okay if we went over to Radiophysics. I want to talk to one or two--" Used to talk to the people over there. But Scheuer was down there at the time, [inaudible] Radiophysics and [inaudible]. Well, everything else is going on, [Bracewell was gone?], [inaudible] Physics Department.

Sullivan: 33:45

Okay. And finally you went to Arecibo in '63, I believe it was?

Hazard: 33:49

Yeah [inaudible] summer of '63.

Sullivan: 33:52

And you told me last time that you built this feed.

Hazard: 33:56

First thing we went out to do is to build this multiple frequency feed to do another [inaudible] test of 273.

Sullivan: 34:02

And had it done-- had Arecibo not done any astronomical observations before then?

Hazard: 34:06

Oh, they have done some. They had been one or two occultation stuff done, I think, with the big line [inaudible], Kundu, I think had done some and [Marshall Cohen?] can tell you. So they have done some, yes.

Sullivan: 34:16

They were occultations also?

Hazard: 34:18

They had done one or two occultations. And-- I'm sure they have. And they said the instrument was just about finished and just getting underway [inaudible], getting going and so on.

Sullivan: 34:37

And there were the problems with the-- illuminating the dish and [crosstalk] [tracking?] This didn’t matter at low frequencies, and also if you're going to do an occultation, you don't have to have accurate tracking.

Hazard: 34:55

Well you need it reasonably accurate, but because the beam width was pretty small and therefore you're only in trouble if they're [inaudible]. At Jodrell you had a big beam [that covered it all?

Sullivan: 35:11

It didn't have to be as accurate as it would be for other things?

Hazard: 35:12

No, no, no.

Sullivan: 35:13

You just had to have a source reasonably near the center [crosstalk]?

Hazard: 35:15

[inaudible]. That's right, so.

Sullivan: 35:21

But what was your impression of Arecibo when you went there? It seems to me to be a rather different kind of place than either Jodrell or Radio Physics or--?

Hazard: 35:29

Oh, it's a different kind of place. I mean it was just this enormous collecting area, you see. It meant that you could do a lot of weak occultations quite easily which is what we were doing. And of course, we did lots of other stuff, not totally successfully, I don't think. I mean looking for odd types of things and [inaudible].

Sullivan: 35:55

Various types of regular stars?

Hazard: 35:57

Yeah, [inaudible].

Sullivan: 36:01

Because you had the most sensitivity?

Hazard: 36:02

That's right. But there we spent a lot of our time developing the analysis techniques and so on, for the occultations. And we also found our own sources by tracking ahead of the moon. They're typically finding good sources so they catalog the sources anymore by this time. [inaudible] the resolution we had to detect [inaudible] sources. So we were gradually changing things. And there was some of the stuff that we did there which, again, I think actually, we detected the [inaudible] some atmosphere on the moon, I think in one case. I interpreted some results that I always intended to do again, but it was very difficult to do low-frequency observations, very low frequency, which is what we wanted to do because of interference we only ever got one good [inaudible].

Sullivan: 36:53

But it would seem to me that Arecibo must have had a different flavor than the Radio Astronomy Observatory per se because there was the ionosphere work [crosstalk] there was a lot of military support?

Hazard: 37:05

[inaudible] Jodrell in a certain sense.

Sullivan: 37:07

Well, that's true.

Hazard: 37:08

And after, at Jodrell there was a lot of satellite work [crosstalk]--

Sullivan: 37:12

Yeah, that's right, that's right.

Hazard: 37:14

--and satellites and so on, so that I think that the fact that there's other stuff going didn't worry us very much. [inaudible] a fairly small amount of time yourself and you don't really worry what's going on the rest of the time.

Sullivan: 37:40

That ends the interview with Cyril Hazard on 3rd June, 1981