Interview with Morton S. Roberts

Description

Morton S. Roberts, 1926-2024. Interviewed 18 August 1972 in Groningen, length of interview: 40 minutes.

Creator

Papers of Woodruff T. Sullivan III

Rights

NRAO/AUI/NSF

Type

Oral History

Interviewer

Sullivan, Woodruff T., III

Interviewee

Roberts, Morton S.

Original Format of Digital Item

Audio cassette tape

Duration

40 minutes

Interview Date

1972-08-18

Interview Topics

Some about Weaver and Struve (and himself), all optical astronomers who got into radio astronomy; 1960-1965 at Harvard with Agassiz 60 ft (mostly extragalactic H I, some other stuff also); also early days as a visitor on NRAO 85 ft and 300 ft.

Notes

The interview listed below was either transcribed as part of Sullivan's research for his book, Cosmic Noise: A History of 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.

Please bear in mind that: 1) This material is a transcript of the spoken word rather than a literary product; 2) An interview must be read with the awareness that different people's memories about an event will often differ, and that memories can change with time for many reasons including subsequent experiences, interactions with others, and one's feelings about an event.

No working file. Audio very soft.

Series

Working Files Series

Unit

Individuals Unit

Transcription

Transcribed by Sierra Smith.

Sullivan

Mort Roberts on 18 August 1972 at the Kapteyn Lab. Now, you were at [University of California] Berkeley when the radio astronomy was just getting going. What year was this now when you left?

Roberts

Well, I left Berkeley in ’60 and the radio telescope at Hat Creek [Radio Observatory], the 85 footer, was just being built. I remember going up a month or two before I left and it’s in lovely country and it was a very nice place to visit but the telescope itself was in bits and pieces scattered on the ground and welding crews were around and the like. The dish itself was a Philco dish and Berkeley saved money by doing a lot of the construction themselves and Philco wanted to get into the game so they gave Berkeley a rather nice price on it. I’m sure they didn’t make any money. And so as far as radio astronomy is concerned, Harold Weaver was the man behind it. He really pushed like mad to get that project going. The inspiration and the reasons- well, the reasons would perhaps be evident, his own interest in galactic structure and a lot of the work that had been done in Holland on galactic...

Sullivan

So it was thought mainly for hydrogen line work?

Roberts

It was thought mainly for hydrogen line work and, in fact, that’s what they did for the first few years and then I’m not sure about OH but they’d been involved in a long term formaldehyde project.

Sullivan

Well, they were part of the discovery of OH emission in ’65.

Roberts

That’s right, the "mysterium", the variability...

Sullivan

Now, [Harold F.] Weaver was an optical astronomer before. How did he get?

Roberts

That’s right. Weaver is amazingly competent in techniques and theory and the fact that it was a different technique wouldn’t faze him and he very quickly mastered it. And I remember a few of the lectures in his course on, I guess, it was galactic structures, it might have been an elementary astrophysics course he gave in which he summarized things very nicely about 21 cm. Roughly about that time [Ronald N.] Bracewell had just come to this country as a young visitor. Struve, I guess, brought him over and, in fact, Bracewell’s book, Bracewell and [Joseph L.] Pawsey [Radio Astronomy], had just come out. In fact, it came out in the middle of his course and his lectures were in essence out of his book with a lot of expansion. That sort of introduced radio astronomy to Berkeley.

Sullivan

There were no dishes there before?

Roberts

No. Space Science might have had a small dish. Sam Silver’s group might have been doing some high frequency stuff but I don’t recall. They were in another building in another area on a big campus.

Sullivan

Now, you mentioned Bracewell was there. Was there anything at Stanford at that time or did he start that up?

Roberts

No. Bracewell started that up. As I recall, he went back to Australia and then he came back to this country, going directly to Stanford. That would have to be checked. When he got to Stanford, he built their interferometer there. I remember one tale from Struve at Berkeley when he was editor of the Astrophysical Journal, he told the tale of receiving this manuscript from an unheard of sort of amateur astronomy, electrical engineer named Grote Reber and it was a map of the sky, if I remember the Milky Way, at radio wavelengths and Struve didn’t know what to do with this manuscript. You know, was this a crank?

Sullivan

This was the 1940 paper?

Roberts

It was a little later, I think. I thought it was during the war. I’d put it in the mid-‘40s.

Sullivan

’42 maybe?

Roberts

Yeah, and he asked astronomers who had not heard of him for obvious reasons and they just were not versed in the problems of radio astronomy at all. And I don’t know if he got any advice from [Double- Es [As in IEE]?], they probably had heard of him. And [Otto] Struve just decided that he couldn’t get any competent referee on this so he decided to take it go out on his own and published it and of course, it, if you will, was the second classic paper; the first being from [Karl] Jansky.

Sullivan

A little bit of a risk he took there.

Roberts

While reminiscing about these tales, nowadays it’s quite fashionable to think of explosions in the nuclei of all galaxies and sort of a continuum going from our own galaxy up to the Seyferts or M82 type, but I can recall a conversation at Berkeley long before this became fashionable, a conversation with Weaver, where we started out talking about the 3 kiloparsec arm and he very clearly outlined at that time, and I would place that in the mid to late ‘50s, ’55, '6, '7, something like that, where he outlined very clearly the picture we have a decade or 15 years later.

Sullivan

Of explosions?

Roberts

Of explosions, that is the weak kind in our own galaxy and then perhaps a whole continuum of this with the Seyfert galaxies occupying the other end the spectrum. Of course, this was pre-quasars and things of that sort.

Sullivan

Did he ever publish any ideas of this sort?

Roberts

No, no he did not. Weaver has published a number of very interesting, in essence, basic papers but he has also, like so many astronomers so busy, so much in his drawer that is not published and this one was just discussion.

Sullivan

Now, Struve is an interesting figure. He’s an example of an optical or now was he an observer or a theoretician?

Roberts

Struve was essentially an observer with an excellent understanding of the theoretical problems and so he could do justice to these discussions.

Sullivan

But now he’s a person, well, starting with this Reber thing but then he was head of NRAO for a short while, so what do you know about him?

Roberts

That’s right. Well, Struve left Berkeley, I believe, the year before I left Berkeley. He went to NRAO. I left Berkeley in ’60. He left in ’59 and I think it was in part his feeling that he owed an obligation. There had been this lengthy search for a director for NRAO. I don’t know who they’d gone after and they weren’t having much success for one reason or another and Struve- whether he was on the search committee or had been approached, I don’t know- but he decided that he would take this position. It is a bit of a shame because he had had, I’d say, a couple years before, a very serious accident at the 60 inch Mt. Wilson. To work far south at the 60 inch at least in those days, you had to get up on a sort of housing by the dome slit- a housing which covered a winch I believe or part of this winch arrangement- and then you, by hand, crank down the windscreen on this shutter. And all one could figure out is that either he slipped or he might have one of these fractional second blackouts and then slipped and he slipped rather badly and fell and broke innumerable ribs and chipped things and was in a hospital in Pasadena for awhile. I believe Bob Kraft was in the mountain, probably at the 100 inch, and was the first astronomer to get to him. They got him down to a hospital in Pasadena and then they shipped him by- that’s not the way to put it- they transported him by ambulance to Berkeley and I remember visiting him there in the hospital surrounded by literature and the like but he was obviously suffering and it was a major accident. And for a person his age, what would have been about 60, that’s a lot to go through and I feel that physically he never recovered from that. He, of course, kept going and then he went to Green Bank just in the midst of the terrible headaches regarding the 140 foot and this didn’t help. He was well liked, as far as I can tell, very well liked by everybody at NRAO in Green Bank and there is still in essence sort of a strange memorial to him there- the Redwood House which was the first director’s resident. And Mrs. Struve wanted to live not in the backwoods, if you will, but close to a road so this was built fairly close to the highway there and somebody said, "Well, coming from California we’ll have to build it in redwood," so the outside siding is that. It is a very comfortable house and now it is sort of the club at NRAO where social functions are often held but it was in essence the Struve residence.

Sullivan

Now, he died while he was still director?

Roberts

No, no. He gave that up after a couple, three years, whether it was for health reason or what, I don’t know. I wasn’t there. I was at Harvard at that time. And he had a joint appointment, half time at Princeton at the Institute for Advance Study and half time at Caltech, and I remember having a very long discussion with him out at the Agassiz station. He was on the Harvard visiting committee and, Struve during my acquaintance with him, when I was a graduate student at Berkeley, there were a number of parties he would give for the graduate students. He didn’t drink much. He might have in his early days at Yerkes, I don’t know. He didn’t then. I remember his once donating a bottle of Cognac to some student gathering, one that when [Namon?] spotted was a little irked at because he had given this bottle to Struve but at this gathering there was a great big punch bowl and it was very tasty and Struve didn’t realize how laced it was and he kept asking me to give him more and he was glad to see an old familiar Berkeley face anyway and so Joey and I had a very lengthy talk with him. He was suffering from insomnia at the time. He had never gotten over his experiences. In the construction of the 140, everything combined; I think primarily that accident that he was just suffering from that and it was made a half-year or a year later that he died.

Sullivan

Now was he the first director of NRAO?

Roberts

He was the first director named as such. The president of AUI, Lloyd Berkner, might have also had the position of acting director, I’m not sure. Heeschen, in essence, was the senior person on the site and so he had many of the headaches, if you will, of the local person [???].

Sullivan

But this still seems very strange, to have a half-optical, half-theoretical guy running, especially at a critical stage when the problems are essentially engineering or was it designed to get somebody who didn’t know the details?

Roberts

Well, in theory the engineering aspects and those things should have been handled by an engineering group. And [Jan Hendrik] Oort is not an engineer and yet he was around and responsible, if you will, for Westerbork and it’s a function of your staff. Now, Struve had had vast amounts of administrative experience at Yerkes, at Berkeley. He knew his way around. He was on all the committees, worldwide recognition. So as far as getting an administrator is concerned and one with a good reputation and the fact that it was a different wavelength than he was used to using shouldn’t be any strike against him.

Sullivan

But why did they have trouble getting a director? Was it seen as sort of a possibility of a dead end sort of situation?

Roberts

Well, all directorships are dead end if you will; that is, where do you go from there unless you become a dean or a college president as has happened say at Berkeley; [William W.] Campbell, I believe, was president of the university or chancellor of Berkeley.

Sullivan

Well, I mean as far as there were too many problems.

Roberts

Here I just don’t know. I’m sure the isolation problem could have been a factor just as it ultimately caused the move of the scientific staff from Green Bank. My own feeling is that it was good in the early days that the scientific staff were located next to the telescopes. There was nothing else to do but science and this helped getting Green Bank onto a nice footing. It’s obvious now, things are running so smoothly and its visitor oriented anyway with most of the time going to visitors that you don’t have to be next to the telescopes.

Sullivan

They didn’t have that policy in the beginning that you had to have more than 60% visitors or so.

Roberts

I don’t know if it was called off in numbers but they had visitors. I was one of the first few visitors back, I think, it was in ’58. The 85 footer had just been accepted. In fact, the people from Blaw-Knox were still coming out to tighten bolts here and there and I came out from Berkeley. I had an NSF post doc fellowship and did a little bit of work with the 85 footer. It was fun.

Sullivan

Ok, so you did some stuff while you were still at Berkeley, some radio astronomy? What exactly?

Roberts

Two things: one, I looked for hydrogen in globular clusters because of my thought that there might be dust in globular clusters and another thing as a result of talking to [Su Shu?] [Wang?], he had some thoughts at that time that some of the peculiarities in the spectrum of Spica might be due to a significant magnetic field and so the question arose, was this a radio star and so I made some X band observations of Spica with negative results. In those days, the reduction of any sort of data was tricky, not tricky but tedious. It was just a chart recorder and while I was there they got a Hewlett Packard digital voltmeter. No that’s it, there were three different stages. At first, you could get just a strip chart record and there was a voltmeter but no print out and so you sat in a comfortable red leather chair and every ten seconds or integration period, whatever it was, you would write down the reading on this digital voltmeter. And then before I left, they got another digital voltmeter with a printout, a Hewlett Packard system, and so this was much nicer but you can see how far we’ve gone in fifteen years.

Sullivan

So, they did have some visitors anyway at that time?

Roberts

Yes, I overlapped with Westerhout who wanted to continue his galactic survey at X band. Of course, he ran into problems of opacity and emission from terrestrial clouds; something that had been vaguely predicted.

Sullivan

X band is what, 3 cm?

Roberts

3 cm. 3.8 as I recall.

Sullivan

Now, how did you get interested in radio astronomy? You were mainly optically trained, isn’t that true?

Roberts

Yes, I got my degree doing optical work, in fact, something old fashioned, star counts, looking at the luminosity function in open clusters. Well, as I mentioned before there was a lot of discussion going on at Berkeley. There was Bracewell exposure. There was Hat Creek going. It was obvious that it was an exciting new area and it was at a time when even a graduate student could have read essentially all of the papers in radio astronomy. This is far from the case now and so it was very evident at that point that it was an exciting area and it wasn’t clear to me that I would be going into radio astronomy at that time but it seemed like another probe. I was always interested in galaxies per se and this seemed like a very nice probe for galaxies and in fact, this is why when I got to Harvard the first thing I got involved in was the line system. At Harvard, they had at that time the most sensitive, the lowest noise system in the world at least at 21 cm. This was a maser which had been built by John Jelley from Harwell and Bryan Cooper from Australia and the great ability at experiment by these two people is the reason that it was in essence was the only successful maser in radio astronomy.

Sullivan

This is in 1960 when you got there?

Roberts

Yes. Well, it had been operating for, I guess, at least a year of that order before I arrived, maybe half a year. There was a paper by a large group of Harvard people, an abstract about that time of the detection of a number of galaxies. They had looked very hastily at perhaps ten of the obvious cases and made detections. It was a small dish but even so, a 60 footer with a 100° system- one could really do very, very well. I might mention, it also helped to have Bloembergen who, as I understand it, was the originator of the three level solid state maser and so he had the theoretical knowhow and the experimental people and so Harvard got on the map in terms of extragalactic hydrogen.

Sullivan

Bloembergen was in the physics department, if I remember?

Roberts

Yes. I guess my interest and background in extragalactic systems which was obviously lacking. At that particularly stage of the Harvard staff, there weren’t people who had worked or had particularly great interest in galaxies. Well, my interest plus the fact that here was the instrument that caused me to put my emphasis in that direction. I did try doing some work with the 61 inch, it was a telescope at Agassiz. It was forever being refurbished, being improved and I remember one night- and I think this was a fairly unique experience- spending the first half of the night with a graduate student observing with the 61 inch and the second half of the night just walking down the hill to the 60 footer and looking at galaxies at 21 cm. I got awfully disgusted with the 61 inch and it was improved after that because we were getting double images. It looked like the support system for the mirror was not operating properly and indeed this was the case. I yelled out strong and they knew there were problems anyway. I shouldn’t take any of the credit. And many of the bellows systems which had sort of a hydraulic fluid in them had leaked. These had frozen and were distorting the mirror and this is why there were double images.

Sullivan

But the 60 foot worked well?

Roberts

Very nicely, very nicely.

Sullivan

So what did you do with the 60 foot?

Roberts

Most of the work that I was involved in was on galaxies. There were some other projects. For instance, Nan [Nannielou H.] Dieter did the high velocity clouds although she was doing galaxies too and that was her thesis at Harvard, M33.

Sullivan

Where is that published?

Roberts

I don’t think it’s been published.

Sullivan

I don’t think so. I don’t think I’ve ever seen that.

Roberts

No. You’d have to get it as a thesis. She, of course, had a big battle in a sense that the argument was, is hydrogen extended around a galaxy or not.

Sullivan

You mean further than the optical?

Roberts

Right, and, of course, this is a poorly defined case because how do you compare isophotes and the like and she said, "Yes, it was bigger than the optical." This, by the way, is an argument that still rages much to my surprise but there is no question that she was right and most at least of the later type systems that have been studied with this in mind show that the hydrogen image even to comparable isophotes however you want normalize them is much bigger in hydrogen than in optical. And you still encounter remarks in the literature that there’s no explanation but I think the situation here is that one is sensitivity limited and they just sort of stopped observing.

Sullivan

Anyway, I got you distracted.

Roberts

Well, it was extragalactic work. Ed Lilley was in charge of the group. Eugene Epstein was the graduate student doing work in this area and I was the staff member doing work in this area. Nan, she was at Air Force Cambridge [Research Center] but had a research associate appointment at Harvard and was using the Agassiz station. There were others, May Kassim... In fact, she was the first person to take me out to Agassiz and I watched her observe. It was not a trivial thing to fill the maser with helium which you had to do yourself; it was an open dewar to make the adjustments that were necessary and if anything went wrong, you had to call Sam [Samuel J.] Goldstein who fortunately lived in the town of Harvard and he was very good about coming out at ungodly hours to help us. Everyone helped if problems were encountered. So it was a fun group. It was built by very capable people. The small technical staff there was excellent that maintained it. The astronomers were a small group who were interested in using it and I’d say by in large, there was good rapport.

Sullivan

And you really had no competition at this time either as hydrogen capabilities go plus interest?

Roberts

Not really, plus the interest, of course.

Sullivan

The Dutch could have done similar things.

Roberts

The Dutch, at that time, didn’t have that much bigger a dish; where they hurt, of course, was in the sensitivity of the receiver and they had made important contribution to extragalactic hydrogen but if you go into the papers, you will see the hundreds of hours that it took them to get a profile or a map of a galaxy and at that time the system was more or less 1000° versus 100.

Sullivan

It was that bad? I see.

Roberts

At least the early galactic work, it was, I think, noisier than 1000. Now it was continually improved and I just can’t date those improvements but that gives you some idea the difference one would gain in integration time. It’s rather interesting with your own interest that at that time we were already talking about the possibility of black galaxies. I think the phrase originated with Ed [A. Edward] Lilley but I’m not sure. The idea was, are there isolated hydrogen blobs of galactic mass of just pure hydrogen.

Sullivan

That don’t [shine?].

Roberts

And of course, we were forever getting bumps which were noise and the joke became is this one and, of course, we quickly found out it was just noise. I remember one period when we got very excited- in fact, it was the time of the Berkeley IAU [International Astronomical Union Meeting]- about trying to look at a comet. There had been reports in the literature about radio radiation, continuum radiation, from a comet, and now my memory fails me whether we tried continuum or line.

Sullivan

Did you ever publish this?

Roberts

We didn’t get anything worth publishing.

Sullivan

This was ’61 at the Berkeley IAU?

Roberts

This was ’61. It was a very bright, supposed to be a bright appearing comet. I can’t recall the details now. I guess I was on the phone with Leland Cunningham at Berkeley getting updated ephemerides but then I was going to the IAU and I left it in the hands of some of the people there. Well, I can’t say I left it; we were all working together. And nothing much came, that is nothing was detected.

Sullivan

Of course, there still hasn’t been.

Roberts

That’s right and the feeling of just another negative paper sort of welled up in us.

Sullivan

Ok. So, what was your program? Was it just first to do a survey of the most obvious candidate to see what the hydrogen looked like?

Roberts

Yes, one wanted to get a more meaningful sample of galaxies with the idea of learning about galaxies obviously rather than just to get hydrogen per se and it was at that point we worked out the problems of estimating total masses. [L. M.] Volders and [Jan A.] Högbum had done this for a regular, I don’t think they applied the same technique to spirals but I’m not sure. I’d have to check with the literature on this.

Sullivan

Where were they published?

Roberts

Volders- Högbum, in the BAN [Bulletin of the Astronomical Society of the Netherlands]. They did 6822 and got a total mass estimate by just assuming a Gaussian distribution.

Sullivan

And you were doing all galaxies that were unresolved?

Roberts

The beam was 50 some odd minutes and there were a few galaxies in Eugene Epstein’s program that were roughly comparable if you take the hydrogen size into account to the beam, that is more or less 1°, some southern ones like, I can’t recall now. In fact, he thought he had seen a bit of rotation so one was resolving in a few of these but a vast majority of the galaxies were unresolved and this made life much simpler because we spoke of milli-Virgo for our calibration. We just tied into Virgo and, of course, we always had great arguments about calibrations and things like that and beam efficiency but it was nice working together.

Sullivan

So was there any galactic work done on the dish at that time or was the OH work later?

Roberts

That was later.

Sullivan

Three or four years later.

Roberts

That’s right. There was, of course, Dieter’s high velocity, well clouds towards the north galactic and, I think, south galactic pole.

Sullivan

Yeah, you mentioned that.

Roberts

Not while I was there. Bob Davis’ thesis had been finished the year before I believe. There might have been but I just can’t recall.

Sullivan

What was his thesis on?

Roberts

It was a section of the galactic plane just doing 21 cm like a number of the studies that came out from Harvard and Holland.

Sullivan

Was that ever published?

Roberts

I think not but I’m not sure.

Sullivan

Now, what about continuum or was it spending almost all of its time on extragalactic hydrogen, the dish?

Roberts

Well, Sam was working on continuum measurements of normal galaxies and perhaps 3C sources. He got some interesting results but if ever there were a situation where source confusion would come in, it’s with a 1° beam. So there was Sam’s continuum work.

Sullivan

Did he ever publish any of that?

Roberts

He had some interesting things that were published. I remember one on normal galaxies in the AJ [The Astronomical Journal]. A student, I think he was an undergraduate at the time, named John Leibacher did a continuum map of Andromeda. I’m sure there are others and my memory just, I think even then May Kassim might have been working on planetary nebulae. As a summer student- there was a summer school- Yervant Terzian was one of the summer students and I think, he did planetaries then. I don’t know if he came interested in them but he made some observations with the 60 footer. We had a babysitter sort of arrangement with the telescope because of the dangers with the helium and the like. There always had to be two students. One who was doing his observing, they were allowed to use the telescope and the other just had to be present just in case of any equipment failure or any danger or any accident and the students griped about this babysitting arrangement or telescope sitting as they called it but it was a necessary safety factor.

Sullivan

This is the end of side A. Please flip over.

End of Tape 16A

Sullivan Tape 16B

Sullivan

Continuing with Mort Roberts on 18 August 1972. So you had some other continuum work at Harvard?

Roberts

Yeah, I recall now that there was interest in the planets and at least I worked on Jupiter and Dick [Huggenin?] and I, well, we made a lot of observations. We sort of logged every day; it was a trivial matter to make a scan on Jupiter if it was at all out and we amassed a large amount of data. And Dick and I looked into this and we convinced ourselves there was a correlation with solar activity- that is, Jupiter did vary, we felt even when we took into account the polarization parameters, and if one looks into the literature, you find that the large scatter in measured fluxes took a systematic pattern if you look at solar activity. This was not received with any sort of enthusiasm by the Jupiter workers though the very problem of how you have a magneto sphere around Jupiter means there has to be some interaction from Jupiter so it’s surprising it wasn’t accepted because you look to the solar plasma for the magnetosphere around Jupiter and that result has sort of sat around with many of the people not being too enthused about it but there are, to my knowledge, at least two independent checks. People in the literature have amassed a fair amount of day to day Jovian observations at decimeter wavelengths and they find the scatter in their data are larger than observational and that if they look for a solar correlation it is present. The NRL [Naval Research Laboratory] people did this. Eric Greisen did it and then somebody came up to me at San Juan and said they too found it and I can’t even recall the name. I’d have to go the abstract.

Sullivan

What frequency were you operating at?

Roberts

21, continuum. If you do it at too short a wavelength, the thermal component is too important so you have to do it at a longer wavelength in the decimeter range. This is obviously not the decametric stuff.

Sullivan

And where was your result published?

Roberts

In the Liege Symposium on Planets in the early ‘60s and it is interesting now that there are three confirmations of it so I would say that the weight of the evidence is pointing to the not at all surprising conclusion that the synchrotron radiation from Jupiter in the decimetric range is correlated with solar activity with a phase lag. And I don’t recall the details now; I would have to go back to that.

Sullivan

Yeah, I can check that.

Roberts

But while there, of course, I had many friends at NRAO having been an early visitor and during one of my visits, I learned of this very nice multichannel, 20 channel, receiver being built there and asked for time on the 300 foot which was also new- it might have been on the air perhaps half a year- and this 20 channel and I believe I was the first to use the 20 channel for this purpose. It was not intended for galactic work. The channels were 100 kc wide and I arrived. I think I had a five or six week run on 300 foot and the contrast between operations at Agassiz and at NRAO were just striking. The day I went on the air there must have been a dozen people milling around, installing the receiver, checking out the telescope, checking out cables, checking out at that time it was punch paper tape for recording and the astronomer just sort of sat back and watched this very competent crew...

Sullivan

[???]. It’s the same as Maryland station. I mean Maryland Point and Agassiz are very similar.

Roberts

Yes, well also I gather Caltech.

Sullivan

I know the contrast you are talking about.

Roberts

And it was so striking. I remember to this day to see all these people working so furiously well into the evening just for you. And here I was a visitor, you can’t say that a staff member is favored at all and it was rather an amusing experience. The telescope was recording data perhaps 20 hours out of the 24 per day, just the telescope moves in the rest when it wasn’t recording and at that time, we didn’t have magnetic tape; it was punch paper tape. And there were two things I remember at the end of the run. One, the telescope operator had prepared a nice little box for me with a note, "Not to be opened until New Years Eve," and, of course, when I did open it, it was full of the little holes or rather the anti holes if you will, the reversed holes that were punched out.

Sullivan

That was your real data there.

Roberts

That was the real data and the other was, I was going to do all the reduction at Harvard which didn’t have a punch paper tape reader and so it all had to be converted to card images and then at Harvard, we dumped the cards onto magnetic tape but a half ton of cards were shipped up from NRAO to Cambridge. And then, of course, once it was on tape, there was nothing to do with the cards and people were very happy to get them because they sold them for scrap paper. It was very valuable scrap paper and this would go into the Christmas party fund and buy a lot of alcohol for it which was held in the machine shop I think or someplace like that.

Sullivan

Half a ton, wow.

Roberts

Well, that run was very successful and all sorts of new and exciting things were obtained. With one pass on the 300 foot, I could see a positive signal where for instance- no, this isn’t nice, I shouldn’t say it- where Jodrell Bank published an extremely low upper limit that is a negative detection with a long amount of integration. I should look up the paper sometime but in one pass on the 300 foot you could see a signal from this galaxy, NGC 2903.

Sullivan

Well that’s not nice, it’s true.

Roberts

Ok, it’s true.

Sullivan

It a better instrument.

Roberts

The year after that, I left Harvard.

Sullivan

You must have been impressed by this army of men.

Roberts

It wasn’t that alone. There were all sorts of factors but being at NRAO, I was never sorry that I went and joined the staff. It’s a fantastic place to work. I can’t think of any nicer facility to have a job. It’s really great and everyone is so congenial, cooperative, capable, cheerful, thrifty, brave, clean, and reverent.

Sullivan

That finishes the interview with Mort Roberts in August ’69.

Citation

Papers of Woodruff T. Sullivan III, “Interview with Morton S. Roberts,” NRAO/AUI Archives, accessed March 29, 2024, https://www.nrao.edu/archives/items/show/15148.