[Cover of Sullivan's book 2009, Cosmic Noise]
Sullivan's Cosmic Noise, Cambridge University Press, 2009


NATIONAL RADIO ASTRONOMY OBSERVATORY ARCHIVES

Papers of Woodruff T. Sullivan III: Tapes Series

Interview with John P. Hagen
At Grenoble
August 27, 1976
Interview Time: 1 hour, 49 minutes
Transcribed for Sullivan by Pamela M. Jernegan

Note: The interview listed below was either transcribed as part of Sullivan's research for his book, Cosmic Noise: A History or Early Radio Astronomy (Cambridge University Press, 2009) or was transcribed in the NRAO Archives by Sierra Smith in 2012-2013. The transcription may have been read and edited for clarity by Sullivan, and may have also been read and edited by the interviewee. Any notes added in the reading/editing process by Sullivan, the interviewee, or others who read the transcript have been included in brackets. If the interview was transcribed for Sullivan, the original typescript of the interview is available in the NRAO Archives. Sullivan's notes about each interview are available on the individual interviewee's Web page. During processing, full names of institutions and people were added in brackets and if especially long the interview was split into parts reflecting the sides of the original audio cassette tapes. We are grateful for the 2011 Herbert C. Pollock Award from Dudley Observatory which funded digitization of the original cassette tapes, and for a 2012 grant from American Institute of Physics, Center for the History of Physics, which funded the work of posting these interviews to the Web.

Part 1 | Part 3

Sullivan

So continuing with John Hagen on 27 August í76. So you're saying the temperature has to be?

Hagen

Somewhere you've got to accommodate these spectroscopic observations that show that there are, fairly deep in the solar atmosphere, temperatures on the order of 20,000į-30,000į. That was not accommodated in this early theory of the Sun's atmosphere that I had and that we were talking about.

Sullivan

Right. Well, let me ask about these eclipse expeditions. First of all, where was that May, 1947 eclipse - the first one?

Hagen

About 20į longitude in the Atlantic.

Sullivan

In the Atlantic, so you went on a Navy ship?

Hagen

We were on a ship.

Sullivan

Oh, I see, can you tell me about that? That's rather interesting.

Hagen

We had a destroyer escort vessel and put a radiometer up on the top of the mast of the thing and I've forgotten now how many of us went on this expedition. But one of the fellows, whose name by the way you should have had earlier and I didn't mention it, [Sullivan: C.B.] Strang, who was elected to go up and be on the top of the mast with the controls to keep that antenna pointed at the Sun as the ship rolled around. It was the most difficult eclipse operation that we undertook because of this lack of stability in the platform. As a consequence, we didn't have a nice, continuous record that we were able to obtain later. But we did have enough to give us a good curve.

Sullivan

And what size dish was it?

Hagen

As I recall, this is from memory, I'd say about six feet.

Sullivan

And you brought this dish along also?

Hagen

Oh, yes. We put a regular fire control mount and put the dish on it up on top of the mast.

Sullivan

Did you know that the Russians were also observing this?

Hagen

I don't think we knew that until afterwards. They were in a port in South America.

Sullivan

Yes, Baya Bay or something like that in Brazil.

Hagen

I can and I've forgotten the other portís name.

Sullivan

[Chica?]

Hagen

[Chica?] that sounds right.

Sullivan

They had the same problems though. Even though they were in a port, they had to steer the whole ship by moving the ropes.

Hagen

They had a little easier problem though than we did, cause they observed at a lower frequency where their machine was [?]. But nevertheless, that was a good observation.

Sullivan

Sort of interesting to have the U.S. and the Russian Navy...

Hagen

But in all this time, I've never talked with [?].

Sullivan

And the second eclipse, is that the one in Alaska in September, 1950?

Hagen

That was at Attu, yes.

Sullivan

In which there's a very nice, from my point of view, Sky & Telescope article. Was this the one that [Grote] Reber went along on?

Hagen

Yes, Reber was along to do a 50 centimeter experiment. He'd been, there was another fellow with him from the Bureau of Standards, his name was Beck.

Sullivan

That's not the same Beck that was at Bell Labs and worked with Jansky?

Hagen

No, this was a young fellow.

Sullivan

And what did you find, you had several different wave lengths - you had 65, 10, 3 and .8 cm.

Hagen

Yes, and we had very bad luck on that thing because a very, very severe storm came through on eclipse day. We had, in addition to the radio, we also had a large optical telescope there. Of course, that was completely washed out. The 8 mm results were completely ruined. I have forgotten about the 3 cm, whether anything useful came out of that or not. We did salvage the 10 cm I know, and I think Reberís results on 50 were not too much affected by the rain. There was a very, very heavy - it was a typhoon.

Sullivan

Really, I normally don't think of them in Alaska. Let's just follow through this whole eclipse business. The next one was...

Hagen

In Khartoum.

Sullivan

In Khartoum. Was that February, 1952?

Hagen

Yes. That was beautiful; that was the best eclipse experiment I think we ever ran. Again, we took a large optical telescope and got good photographs of the corona and the inner corona. We had a 10 cm radiometer and an 8 mm radiometer. Unfortunately, we didn't take a 3 cm along and it's turning out now that that was a real oversight because one of the most important experiments you can do today is to get a good eclipse observation at 3 cm wavelength.

Sullivan

Because that level is important in theory?

Hagen

Yes, yes.

Sullivan

And why is that?

Hagen

Because of the- this will come out of the paper Iím about to publish. It's the 3 cm flux from the quiet Sun is symptomatic of a very, very interesting part of the solar atmosphere which is right below 10,000 kilometers height above the [?]. And a 3 centimeter eclipse observation, a good one, will answer a lot of questions.

Sullivan

I see. And I think there's still one more, is that right?

Hagen

Yes.

Sullivan

You reported on one at the Jodrell Bank Symposium in 1955.

Hagen

That eclipse was in [?], Sweden. And there again, we didn't have the best weather, but we did get good results at both 8 millimeters and 10 centimeters.

Sullivan

What is the purpose of going to an eclipse after you've been to Khartoum, to go to Sweden? What can you learn new?

Hagen

Well, it's not what you learn new; it's what you learn better. The Sun is never absolutely quiet - there's always some small active region somewhere on it, and the existence of the active region, especially if itís anywhere near the limb, makes it difficult to reduce the eclipse observation and introduce a degree of question in your mind as to the validity of what you're seeing. And therefore, you do like to have two or three good eclipse observations with the distribution of the activity over the surface of the Sun is different from what it was before. This would confirm the conclusions that you drew. So we went to Sweden essentially to confirm what we did in Sudan.

Sullivan

Was there anyone else observing eclipses in centimeter wavelengths through these years?

Hagen

Not significantly.

Sullivan

Or doing work that could really be compared with yours? Maybe interferometric, no, that's not true.

Hagen

Well, interferometry, yes. Covington had a new and large array of sensitive can call it an array - we can call it an array- which he used at 10 centimeters, and that allowed him to confirm limb brightening at 10 centimeters. But I don't think of any group doing the same kind of eclipse work.

Sullivan

I don't think of any. Is that all of the eclipses? Have we hit them all?

Hagen

All the NRL eclipses, I think.

Sullivan

Right. Well, while this was going on, this was obviously one of your main interests, but there were other interests that were developing in the branch. Could you tell me what these were and who was really the force behind them?

Hagen

Yes. Last night I mentioned notes here. Letís see what we covered. We did refer to the design and construction of that 50 foot antenna.

Sullivan

Yes tell me a lot more about that - how that came about.

Hagen

I've forgotten the exact date, but in the late 1940's we became convinced that a large steerable antenna was needed, for centimeter and millimeter work. We looked at many different designs and finally settled on a particular design and let a contract with Collins Radio Company to build the antenna. It was constructed in [?] segments which could be unbolted. So they machined the thing in Iowa using a template and then a milling cutter which was on a beam and could be programmed to follow a parabolic curve. They machined the thing there and disassembled it, drove it to NRL and reassembled the thing on the roof where we of course, went through a long series of mechanical checks to bring the thing back to the proper parabolic configuration. Once we had that up...

Sullivan

Was that more difficult than you thought it would be?

Hagen

Well, the testing was a difficult thing, yes. When you get something that big, and you have to measure things as small as you have, because we tested that to, I believe, either a tenth or twentieth of a wavelength, and I can't remember whether it was 8 or 5 millimeter, so that we were dealing with...

Sullivan

Oh, you wanted to use it at 8 millimeters.

Hagen

Oh, yes.

Sullivan

It never was, actually, though.

Hagen

Yes it was.

Sullivan

Oh, okay. Youíll have to tell me about that.

Hagen

And so carrying out those tests was difficult, we used a combination of mechanical and optical techniques to do it.

Sullivan

Can you tell me about these techniques, because this was all new territory, I think. This was the largest dish of its kind, wasn't it?

Hagen

Well what we did to test the thing out was to build a template, which could be mounted on a post coming through the center of the antenna and then swung around and measurements made between the template and the antenna. That was the primary method of measurement. We also used a- what did surveyors call it?

Sullivan

A theodolite?

Hagen

No, it wasn't a theodolite- it was a thing made by the Wilde Company in Switzerland; it's really what amounts to an optical lever. With that you can measure precisely at a distance, using a rod, and we used that to probe all over the surface. And the net effect was that we were able to confine the measurements of the template and measurements by the optical techniques or really surveying techniques, to measure the nature of the surface of the antenna. Following that, of course, we did the more practical thing of checking the pattern and the gain of the antenna at short wavelengths. That was no easy task, because you had to go a great many miles to get out into the front upper region. To really accomplish that we attempted to use a blimp which would fly through the beam way out to north of us, between us and [?] where it came from. And that was a very interesting series of events. We did get pattern measurements out of it, but a good deal of the time the blimp didn't know where it was.

Sullivan

You were plotting the right place, but they weren't there?

Hagen

We found out a lot about blimp navigation.

Sullivan

Now how far away was this blimp actually?

Hagen

Thirty or forty miles.

Sullivan

I see. And so that was actually the means by which you tried to gain...

Hagen

Initially. And then after that we used point radio sources.

Sullivan

You haven't told me about the mount. The Collins Company did the surface.

Hagen

The work on the mount we did ourselves, along with, and I'm a little bit foggy on the help that we had here. We had help from another Division in the laboratory prior to the fire control division. What we did was to use an old Navy gun mount, and then we had Collins build a computer that was really an analog computer.

Sullivan

Yes, I've seen that.

Hagen

Oh, you've seen it?

Sullivan

Oh, yes.

Hagen

To go from earth coordinates to celestial coordinates. And that was a very well made device - it worked quite well. Our biggest difficulty with the mount was one of stability. That was the mount was designed and built to operate a massive gun, but the gun didn't have the moment of inertia that an antenna has, and so we had to use [?] devices in the mount to squelch the oscillation. That was our biggest problem in quieting down the operation of the mount to get rid of these oscillations.

Sullivan

Was this especially after slewing or was this even when you were tracking?

Hagen

No, especially after slewing, but once you started tracking, it was all right. But if you moved the antenna rapidly, then that was very difficult.

Sullivan

Just for the record, what size gun was it mounted to?

Hagen

I can't put it on the record, because I don't recall if it was an 8 inch gun or big 16 inch.

Sullivan

I think I remember twin 8 inch someone else may have told me that.

Hagen

That may well be.

Sullivan

Now, how long was this whole process - calibrating the dish and so forth? It must have been quite a while?

Hagen

I would think, I don't remember, but I would say certainly all of one year. It took us a long time.

Sullivan

And when was it finished - can you recall?

Hagen

It must have been around 1952.

Sullivan

And then what do you do when you have such a nice, new toy?

Hagen

We did several things. We, of course, investigated the possibility for use at 8 millimeters, and we did make quite a few observations of the Sun at 8 mm. We never did carry that through to the point where we published them, but we had contour maps of the Sun. We had hoped with the resolution that we would get with that, that we would see the limb brightening at 8 mm. However, if you look closely at the problem- if you want to see limb brightening, you have to have a beam that's much, much more narrow than we could get with a 50 foot dish. To really see limb brightening at 8 mm, you'd need a dish that's couple of hundred feet in diameter at least.

Sullivan

What was it - a couple of arc minute beam or something like that?

Hagen

The beam on this dish at 8 mm, I think, was about two arc minutes, if I'm not mistaken.

Sullivan

Why wasn't this work published?

Hagen

We had so many other things we had that we were doing, we just didn't see the real advantage of publishing it.

Sullivan

When you say 'we', was this Gibson that was working on this?

Hagen

With me on this 8 mm, it was Gibson and Sees, I believe, and myself.

Sullivan

Was there an internal report or anything like that?

Hagen

I don't remember. I rather remember that we didn't even write an internal report, when we did not observe, and began to realize that we shouldnít observe, the limb brightening. What we did observe was the uneven contour of the Sun due to the active regions. However, we had other things that we wanted to do with the dish, so we couldnít see using it at millimeter waves for the Sun. We thought it would be much better to do some of the centimeter work where we saw a chance to make a real quick breakthrough. We looked for the distribution of radiation along the galactic plane, for example, and observed the X-2 region.

Sullivan

Let me ask about that experiment because that's a rather important one. You'd been working on free-free theory and so forth so you must have been well aware that HII regions would be detectable at certain level, was this in your mind as you were building the dish that this was going to be...

Hagen

Yes.

Sullivan

So I guess it wasn't a surprise then that you detected these things.

Hagen

Oh no, not at all.

Sullivan

But nevertheless, it was a first, and I guess it was published in 1954?

Hagen

Thereabouts.

Sullivan

And you also measured the flux of some other things besides H II regions at 21 cm.

Hagen

That's right. We measured the flux of some of the brighter radio sources at 10 cm and I believe, at 3 cm. That's an interesting point. We, this group that I had, were well indoctrinated on precise calibrations and so we had very good measurements on the flux of several, five or six, of the brighter radio sources. If you look back through the records, you'll find that if you extrapolated our results, they didn't meet the results of the people in England who had been doing work on flux of sources, and so you're led to a necessary curve. Over a period of years, the S has gone out of that curve, and the lower frequency fluxes have gone down to the point where they jive with these early NRL centimeters.

Sullivan

I see; that's interesting. I hadn't realized; I'll have to do some checking on that. Now what about the 21 cm hydrogen line?

Hagen

At that time, we decided that we had an excellent opportunity to do work at 21 cm and so we got a 21 cm receiver, purchased it from [Harold Irving "Doc"] Ewen, and the very first thing, as I recall, that we did with that, was to begin to investigate some of these bright sources. And I believe it was Taurus that we first observed and observed for the first time absorption of radiation by the hydrogen clouds.

Sullivan

This was not what you were looking for, this was just...

Hagen

We were not looking for that; it was just chance.

Sullivan

Right. Let me just ask you a question before we go on. The 21 cm line was not part of the original impetus to build the dish. It just came along in the process while the dish was being built.

Hagen

That's right.

Sullivan

Okay, now back to this story. I'd be interested in an account of this discovery, because when the line went the wrong way, there must have been a lot of checking.

Hagen

There certainly was. And a lot of back of the envelope work, trying to understand why the thing did go the way they did go, and we finally convinced ourselves that 'yes' we were seeing absorption. We then went and looked at Cassiopeia and found the same thing. And we then began to realize that there was more than an intellectual interest in this thing because by that time we had a foggy notion of what the spiral arms were like. The fact that we had this absorption showing up as it did with the velocities of Cassiopeia, we were able to say that Cassiopeia was a lot closer than astronomers earlier had thought. So I think, for the first time, did a rough measurement of the distance of Cassiopeia.

Sullivan

Right. I want to talk about that quite a bit. Let me ask, this probably wasn't right at the beginning, the distance method came upon you, or was it? The first thing was just sort of to figure out what this absorption meant.

Hagen

That's right. The first effort was on the Taurus experiment to really understand what the absorption meant and how you could explain it away theoretically. Then we went, I don't know, I say then- after that time, we went to Cassiopeia and saw absorption again and then set about to really explain what we saw and when we did, we did two things: one of them was to get a model of what the hydrogen cloud must be like in order to provide that kind of line picture that we saw. And also as an added thing, we realized that this tells you that Cassiopeia cannot be as far away, it was just [?].

Sullivan

Based on the Dutch work on galactic structure and emission.

Hagen

Yes, exactly.

Sullivan

Do you remember specifically how this idea of using it as a distance method came about?

Hagen

No. The people, [A. Edward] Lilley, McClain, and I were working together on that thing and I could not tell you frankly who came up first with that idea. It was a team effort, and when you think back, you don't know who did it.

Sullivan

But now there is another question relevant to this, there were two papers published as you probably remember, Hagen and McClain in ApJ in 1954, and then Hagen, Lilley, and McClain in in 1955, which is a much more extended paper going into all of the theory of absorption and such. Did Lilley join the group?

Hagen

Lilley joined the group at about that time.

Sullivan

Just after your discovery?

Hagen

Yes.

Sullivan

And it seems from a reading of the paper that you and McClain did not have quite today's idea anyway, I want to avoid saying the "right" idea, about the nature of this absorption - namely that, it's only a couple of sentences thatís relevant but it seems like you were thinking of the source actually blocking the hydrogen behind the source. Is that a fair interpretation?

Hagen

No. I think McClain and I felt- I how you arrived at that but McClain and I, I think if you look at the paper, said that the hydrogen was in front of the source. Initially, when we first ran into this, our early-off-the-cuff discussions were, "Could it possibly be the source blocking the hydrogen?" But by the time we reported the paper I think we had that straightened out.

Sullivan

Well, I have it in my room, so are you at [URSI] Commission 40 tomorrow morning?

Hagen

Yeah.

Sullivan

I'll bring it along and we can take a look at it.

Hagen

I'd like to see that.

Sullivan

It seems itís the other way, but I don't have it.

Hagen

You're dealing with a memory of way-back-when.

Sullivan

So what you're saying is that, in any case, it wasn't clear which way it was.

Hagen

To begin with, we had certainly suspected it both ways. But my recollection is that by the time we had published that first paper, that we had sorted that out.

Sullivan

Is it fair to say that Lilley did most of the- I haven't talked to him yet- that Lilley did most of the modeling in the second paper? That's what it looks like from the outside because he is the different person.

Hagen

I think you'd say that- I wouldnít want to take credit away from McClain actually. We did work awfully closely together as a group, and again, it's awfully difficult to say, "Yes, this fellow did that and that fellow did that," because things were going back and forth. But there's no question but that Lilley was the spark plug there, there's no question about that.

Sullivan

Was he one of the first people who joined besides the original group? I guess Nan Hepburn [Nannielou H. Dieter], as she was called then, also...

Hagen

Oh, I had forgot about Nan.

Sullivan

Was that true that you didn't really have a lot of new people until about this era?

Hagen

We had people, Nancy Roman worked with us for a while, you know.

Sullivan

But that was a little later.

Hagen

Yes, that was a little later, late Ď50s. The group was pretty stable, there weren't too many people coming and going. Few people came and few people left.

Sullivan

Of course, that's been true for the last ten or twenty years also. But it's also interesting that no one else bothered to get a Ph.D. in astronomy. Do you have any thoughts as to why, did it just seem like an unnecessary thing to learn astronomy or was it that the best way to learn astronomy was by doing it?

Hagen

When you say nobody else, do you mean in the...

Sullivan

In the NRL group.

Hagen

In the NRL group? Well, that's awfully hard to explain. First, it takes a tremendous amount of effort to work at a place like NRL and then at the same time go out and get a Ph.D. Now did [Robert J.] Coates did. Coates did and he's the only one I think that did. It just...

Sullivan

No, you're right and once you've got a family...

Hagen

It's more than a lot of people want to do.

Sullivan

Okay. Now you've brought up this meeting that was held in January of 1954 which was held in Washington, D.C. And you actually gave in Science that year, you gave a report of that meeting, this was a rather important meeting I think, especially for American radio astronomy. Could you tell me about that?

Hagen

I wish I could tell you - I didn't know I was going to be talking with you or I would have looked at some of these things.

Sullivan

Well, once again, when the transcript comes, maybe you can...

Hagen

Memory is a horrible thing. I was afraid that I would say things that I think are true, but really aren't. You know, it's awfully hard to remember some of these things.

Sullivan

I have a lot of other cross-checks. Other people tell me about the meeting, too.

Hagen

As I recall it, the reporting of that meeting was pretty thorough, and I think your best way of finding out what went on at that meeting is to read the report.

Sullivan

You don't remember particularly the atmosphere of the meeting, or maybe something that couldn't be garnered from the report?

Hagen

No, I was too damned busy at that time to really go around feeling for atmosphere. I couldn't tell you.

Hagen

Sullivan

Well, let me ask this about that meeting, I have a feeling or memory, my memory once again, but not from twenty-five years - one year maybe, that the purpose of this meeting was to sort of assay the state of American radio astronomy and to see whether it would be worthwhile going to a national observatory.

Hagen

Yes, that's right. Thatís exactly right because at that time, [Donald H.] Menzel and I, and later Lloyd Berkner were discussing the feasibility of establishing a national observatory with a large facility. And this was essentially a build-up to that.

Sullivan

So you were in favor of that all along?

Hagen

Oh, yes. I worked very closely with the observatory in the organizing sessions that went on which led up to the development of the national radio observatory. And itís not on the record, but Dick [Richard] Emberson and I are the two people who spent a couple of weeks down in the wilds of West Virginia and Tennessee and Virginia looking for a site and picked that site in Green Bank.

Sullivan

I see, making noise measurements.

Hagen

No, we didn't make noise measurements. We looked at what the terrain was like and we kind of investigated what was nearby. And decided just on the basis of that that Green Bank was probably the best. But this was a part- this was an attempt to show that in the United States there was a respectable amount of work going on in radio astronomy that required the kind of facility that we were going to build.

Sullivan

But now a national observatory at that time was a new concept.

Hagen

Brookhaven.

Sullivan

But in astronomy, I mean.

Hagen

In astronomy, that's right.

Sullivan

And certainly no other radio groups were operating along these lines. So how did this - did it come out of Brookhaven, basically?

Hagen

It came out of the notion, the idea of Brookhaven, yes.

Sullivan

And...

Hagen

We had been talking, we'd built the 50 foot dish and so Siece and I spent endless hours looking at bigger dishes. We thought about 400 foot dishes and had all sorts of schemes as to how to build them, but behind that was the tremendous amount of financial support that would be required. We knew that we couldn't get that out of the Navy, so I talked with Menzel for example and with Berkner and out of that came, we thought, "Maybe if we had a joint effort, we could do something like that." And again, it's hard to trace it step-by-step, but that led to the meetings that we held under the auspices of the Associated Universities, where we discussed the possibility of some kind of joint effort to build a large facility and discussed what that large facility should be.

Sullivan

And what did you think it should be at that stage?

Hagen

At that stage of the game, we were just thinking in terms of one big antenna, as large an antenna as the techniques of the time would allow us to build, and the funds, the financial situation would allow us to build. And we realized in the meetings that the antenna would have a dual purpose, that possibly it would be used both for solar and for galactic work. But evolution took over and what went on, of course, at the National Observatory when it was built, was that there was very little of any solar work done. But in the beginning, solar and galactic were both...

Sullivan

And so it was going to be a 300, 400 foot antenna good to- what sort of wavelength were you...

Hagen

Well, we wanted to get down to a short centimeter wavelength if possible.

Sullivan

So this might be called sort Jodrell Bank sort of outlook, that a big dish was the way to go.

Hagen

That's it.

Sullivan

Well, this pops in my mind and leads to another question. And then it might seem that once NRAO didn't quite get all the funding in the beginning, and so forth, that might have been hoped for and that for several years, there was only a single 85 foot and so forth, was Sugar Grove then at all, is it fair to say, seized upon as possibly a way one could realize what hadn't worked at NRAO in terms of getting a big steerable dish?

Hagen

Well, I don't know the whole of that Sugar Grove story, and part of it you couldn't tell if you knew it. That Sugar Grove came out of really the NRL work; but to get to the Sugar Grove stage outside of the radio astronomy group at NRL.

Sullivan

For military purposes?

Hagen

Yes. And well, I guess the less said about that Sugar Grove thing, the better.

Sullivan

Well, it's part of the history.

Hagen

It was obviously a- the problem there was not technical. It was management problem. If technical people had full control over what was going on, at least if I were one of the technical people, that thing would have been built.

Sullivan

Yes. Some other people have told me some aspects of this thing and apparently, the Bureau of Yards and Docks felt that they were the ones that had to get involved and they may have known how to build yards and docks, but antennas are something else.

Hagen

That's right.

Sullivan

When did you leave NRL?

Hagen

I left NRL in- oh gee you see in 1955, I by that time, I had become head of the Atmosphere and Astrophysics Division.

Sullivan

I see, you were head of the whole division.

Hagen

And we had all this rocket work going on and we had developed the idea of a satellite capability, and so when the IGY came along, and the Vanguard program was started, I resigned the directorship of that, and that was in 1955. I think NASA was born in 1958, and Vanguard was one of the building blocks of NASA. So Vanguard was transferred over to NASA and I went over to NASA.

Sullivan

I see.

Hagen

So I sort of walked out the back door of NRL.

Sullivan

Okay, I'd like to ask you a couple of things about that and we can finish up the radio astronomy before then. You mentioned about the distance of Cas, which indeed, was a controversy for a couple of years because people with great authority like [Rudolph] Minkowski said that the thing must be at such-and-such a distance, let's see, how did the thing go? You wanted to have it at around 3 kiloparsecs, just between the what we call the Orion and the Perseus arms and Minkowski was saying that the proper motion study said that it must be much more distant. Or no, did they say it had to be very close?

Hagen

No, further away.

Sullivan

And Ed McClain actually showed me a letter that he had from [Walter] Baade saying that you were right, essentially, after this whole thing settled down. He was very proud of that letter, sort of explaining how they went wrong. Were you involved in this at all?

Hagen

Oh, yes.

Sullivan

Can you remember from the meetings of that time, what went on?

Hagen

Not really.

Sullivan

Perhaps the Jodrell Symposium in 1955.

Hagen

Well, I was going to say, the thing, we didn't treat that thing as at all contentious. I reported it in a very matter-of-fact way with Minkowski sitting ten feet away from Ed at this Jodrell Bank meeting, and as I recall it, there was no...

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Modified on Monday, 29-Apr-2013 14:34:39 EDT by Ellen Bouton, Archivist (Questions or feedback)