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Oral History Transcript — Dr. Arthur D. Code

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Interview with Dr. Arthur D. Code
By David DeVorkin
At the National Air and Space Museum
October 1, 1982

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Arthur Code; October 1, 1982

ABSTRACT: Discusses his career in astronomy and astrophysics through his student days at the University of Chicago (PhD, 1950, astronomy and astrophysics); and his teaching and administrative positions at the University of Virginia (1950), the University of Wisconsin and Washburn Observatory (1951-56; 1959- ), and briefly with the California Institute of Technology at Palomar and Mt. Wilson Observatories (1956-58). The interview centers on his work in space astronomy, with emphasis on his use of an X-15 airplane for UV stellar spectroscopy, and his role in the development of the OAO series and Copernicus. Also discussed is his work with instrumentation, especially photoelectric photometry, and his theoretical interest in cosmology.

Transcript

Session I | Session II

DeVorkin:

We ended up by bringing you to the point where you were being courted by the University of Wisconsin. You were at Hale Observatories now. The offer came from the University for you to return as Director?

Code:

That's correct. It wasn't something I was looking for. You were asking, with respect to going into a space program, whether that was a condition when I went back to the University of Wisconsin; and why me, when many other astronomers weren't willing to make such a commitment. And I think that the fact that I had an opportunity to start something new had to have been important in that decision.

That is, in thinking about whether or not I wanted to accept the position at the University of Wisconsin, I thought; well, they don't have the big telescope and clear skies there, although there was a new observatory just being commissioned at Pine Bluff. But there was the opportunity to do a new kind of astronomy. And the University of Wisconsin was as good, or perhaps a better home base for that than Caltech would be. Probably, had I not been offered this position, I would have opted as most astronomers did to continue doing what I was doing, because I was interested in that and knew I was getting somewhere there.

DeVorkin:

You must have talked to people at Caltech about these ideas. I'd be interested in their reactions. Who did you talk to?

Code:

Now, first of all, there was of course JPL. And there was an astronomical program that was under consideration at JPL at that time. Bill Baum was involved with it. And this was in collaboration with the Redstone Arsenal, and a payload that one might launch in their vehicle.

DeVorkin:

Yes. Was this in response to Berkner?

Code:

No, this had gotten generated before. The Army was talking about whether there could be some scientific payloads in the Redstone missile. And so JPL then was the contractor with the military, the Defense Department. And the experiment that was proposed was one of measuring the cosmic sky background. You get above the earth's airglow to address the problem of Olber's Paradox; how bright is the extragalactic background? So it was a simple photometer with a wide field that would just make measurements of the background. The astronomer most intimately involved in that was Bill Baum.

DeVorkin:

Yes, now this was a visual range photometer, nothing unusual.

Code:

That's right. So the main advantage was that you get above the airglow to carry out the experiment.

DeVorkin:

Did he ask you to participate?

Code:

I suppose yes, we talked about it quite a bit, and I was interested in it, and in the design. Nothing ever came of this experiment.

DeVorkin:

Did you know why?

Code:

I believe that this experiment was proposed in response to Berkner's request, and so was one that was considered by the panel. That undoubtedly meant that there were changes at JPL, so they had other things to do, or were no longer ready to support it. And I would think, probably what happened was that Bill Baum wasn't ready to devote time to it in some different environment than just dealing locally with JPL people. I don't remember for sure. But the characteristic of most proposals were: here is something, the proposer says, that I think is interesting and important to do, and somebody ought to do it. They weren't ready to sign up themselves. So the first mix was actually of those people who said, "Here is a good program and I'd be glad to work on it myself." That's how the choice finally narrowed down, because it was a very small number of people who said that.

DeVorkin:

Who did say that?

Code:

It was almost exclusively members of the panel who selected. And all the panel members were recruited from people who were interested, and had responded to Berkner's letter. Leo Goldberg, Martin Schwarzschild, and Fred Whipple. I remember other participants; I don't remember their having experiments involved then.

DeVorkin:

Did Spitzer have a proposal? Or Friedman?

Code:

Herb Friedman, yes. I guess Schwarzschild was speaking for Spitzer. I don't believe Lyman was a member of that first panel. At any rate, going back to the University of Wisconsin, it wasn't a condition of employment, it was one of the things that I said I would get involved in. It was just tacitly assumed, of course, that whatever directions of research you want to go in; the University will give as much support as they can. That was Wisconsin's attitude.

DeVorkin:

Did you talk about the Space Astronomy Laboratory at that time?

Code:

No we just talked about doing it within the astronomy department. A space astronomy laboratory just grew from the departmental activities and we finally put a name on it, early in the days, we called it SAL, or Sal, or Laboratory. And at that time we just had a part of a rented house; and later on a rented warehouse for many years, which we also for a period of time shared with meteorology, a space program they started up. It was that way for about a decade, just rental facilities where we had the laboratory.

DeVorkin:

What of the reaction of people from Caltech? Was there anyone, say Jesse Greenstein, who was negative about your decision to go into space astronomy? Or about your leaving?

Code:

Negative about my leaving, and made some efforts to convince me that I ought to stay. It was just my leaving that was the subject of discussion, not a space program. And I didn't know what would evolve in the way of a space program myself. That was only an element in my decision, and not a major one, I think, at the time. Sure, there were some people around Caltech that I talked to about space astronomy right after Sputnik. One of them who was at that time very enthusiastic about doing things as Larry Helfer, who is now in Rochester. And I discussed it with Bill Baum.

DeVorkin:

Was he pretty encouraging?

Code:

Yes I think so. Now Don Osterbrock was an assistant professor at Caltech, and he had a fond spot in his heart for Wisconsin as a place to live, where his wife's family was, and he was a bit dissatisfied that he was still an assistant professor at Caltech. I offered him a position at Wisconsin and he decided to leave Caltech and come to Wisconsin at the time that I did. And of course, he was aware that in addition to ground-based research activities, that we had an interest in starting up a space astronomy program. He thought that was a good idea and was supportive of it.

DeVorkin:

What would you point to in your own career, in your own interests, that made you one of the very few people at the time in astronomy who dedicated part of their work, and eventually a large part of their work at least, to space astronomy, especially at the first outset of Sputnik?

Code:

That's a very difficult question. I think I always had a lot of imagination, and liked the idea of something new and new discoveries; and had an instrumental background. The other feeling was that obviously, telescopes are going to be in space. Astronomers dreamed of observing above the earth's atmosphere for a century or so, and it was going to be done. It would be a shame if telescopes were put in a satellite and the wrong filters were in there that didn't take advantage of the fact that they were above the earth's atmosphere, and so there better be astronomers involved. It would be done whether there would be good astronomers involved or not. And so somebody had better do it, and I decided I'd be one of those somebodies doing it.

DeVorkin:

Did you talk to anyone within NASA?

Code:

NASA didnt exist until well into the summer of 1958.

DeVorkin:

That's right. So how did you expect you were going to be able to participate? It was after the Lloyd Berkner letter, and you were thinking of 100-pound payloads.

Code:

That's right, and we at Wisconsin, Ted Houck, a very good instrumentalist and photoelectric photometry and image tube person, was very interested, too.

DeVorkin:

Was he trained in Wisconsin?

Code:

Yes he got his Ph. D. in astrophysics at Wisconsin. And we set about a conceptual design which we would call a design at that time, of a 100-pound instrument that was a 100-pound satellite. We were talking about the entire power supply, or solar cells, and the communications equipment, and the photometer, and all that it would require for a small satellite.

DeVorkin:

Did you actually have rough engineering drawings feasibility studies?

Code:

We had some pencil drawings, and later on after NASA got created, there was some funding. We had something a little more in the way of engineering designs. Everything that we were doing was simply an extension of the kinds of things we did on the ground. So there wasn't any new state of the art, beyond extending things to the ultraviolet really.

DeVorkin:

It was the ultraviolet you decided to go toward?

Code:

Yes. This was simply the first step, which looked feasible and didn't strain the state of the art. At higher energies — x-ray and gamma ray — there is detector technology that didn't exist at the time. Any kind of imaging required real pointing systems which was something that didn't exist. But just to make photometric measurements with fairly large entrance apertures with a satellite, why do it unless you take some advantage of going into space; to get that part of the electromagnetic spectrum that you can't measure?

DeVorkin:

So you were looking at sky background just as Bill Baum suggested?

Code:

No, looking at individual stars. The first question that interested us was 0 or B stars, and of course those were the ones I had mostly worked on. Most of their energy is in the vacuum ultraviolet, and when you compare the energy distribution of an 0 star from ground-based observations with the prediction of model atmospheres, well, you don't have much leverage in the problem, because most of the energy is in the ultraviolet where you don't have the observations. So that was the main scientific incentive in doing photometry in the ultraviolet. The satellite was not spinning. We would dump the momentum. In the model we had you dumped it with yoyos. Do you know what yoyos are?

DeVorkin:

Well, you'd better describe them.

Code:

You take a pair of weights and they are on the end of strings, and you wrap it around a post and an object is spinning. You let go the clamps that are holding these weights, and it unravels. You don't have the end tied and they just go off into space, and that carried the angular momentum away. So you throw it away that way. (laughs). And we built some of these and ran them in the shop, and indeed had something spinning fast, and spun it up and just had the weights held with masking tape or something of this sort, so at a certain speed it broke away. Then the spinning wheel came to a screeching halt as the weights went sailing out (chuckles). And a lot of the little things were possible when you get rid of the angular momentum that way. Then you just use fly wheels to move the spacecraft around from one position to another. And you have to keep track of stars just as you do with a spinning spacecraft. It's a little puzzle to figure out where you're pointing from the star patterns with a spinning spacecraft.

DeVorkin:

How were you going to do this, with television sensors?

Code:

No. See if you have an unstablized rocket that just spins, you will get a number of signals from, bright stars as it spins around. And the first iteration is solving such a problem as: "Well, let's say the brightest thing we have here is Vega. If that's true and then the repetition gives you the spin rate, then here is another bright star that is so many degrees around Vega. Are there any bright stars with those number of degrees away? Yes, so it must be going this way, and if it's going this way, then the star that you pick up next is down here." All right, now you can imagine doing this on a slow basis where you are able to stay for awhile on each object. And once you've learned your way around, then you know how to slow from one object to another, and after awhile, your momentum will have accumulated, and so you let go another yoyo. You dump angular momentum. It works something like that.

DeVorkin:

Meanwhile, you had a filter system in your photometric system to give you an energy distribution curve of some sort?

Code:

It employed photometers with interference filters in the ultraviolet. They didn't exist and you couldn't buy them, but we had made interference filters before in the visual, and figured we could make them. And ultimately we did, and we still make interference filters. Two of the interference filters in the wide-field planetary camera for Space Telescope are ones that we made. The first experiments that we actually carried out, however, included a small photometer telescope we built with a two-inch lens and a photomultiplier at the focus with a visual filter in it. And this we mounted at an angle on essentially a radio sonde package for weather, that normally tramsmits pressure and temperature. This was suspended from these large weather balloons, and we sent the weather balloon up. The telescope was at an angle with respect to the suspension. So you have a torsion pendulum, and so the telescope would scan around the sky, and then the data was telemetered down. So this was the first observation we got from above the surface of the earth. It was measuring sky brightness. It was measuring some of the techniques. We had a little label on it, if anyone found it to return it. This was launched from Picnic Point in Lake Mendota, University of Wisconsin.

DeVorkin:

Oh, that's right downtown.

Code:

Yes. And it was found by Christian Sneek, a farmer in northern Illinois. That's not a an easy name to forget, I guess! (laughs). He returned that box.

DeVorkin:

Do you still have it?

Code:

I don't think we have that photometer. Then when I was on an airplane one day, I looked out the window, and the sky was really dark blue that day at that altitude. I walked back to the end of the airplane, and I noticed light came through a window with a sharp shadow line, and the auto pilot was on. And it was drifting slightly back and forth. So I measured that with a ruler and then sort of paced off how far it was from where the light was coming in, what kind of an optical lever I had there. I don't remember the answer I got, but it looked like pretty good pointing. If you don't do much to an airplane, and the sky looks a little dark, you ought to be able to fly a telescope in that. I heard that the X-15 gets above the ozone layer, so how about making measurements in the X-15? Now, the incentive was that the first ultraviolet measurements of stars with rockets by the NRL group gave some very curious results. First, the stars were very faint, and some bright stars had big halos around them.

DeVorkin:

This was Friedman's work?

Code:

Right. Their detector was actually a big bundle of hypodermic needles to form a collimator, and then a photomultipler behind. Perhaps the halo around Spica was just scattered light. At any rate, we thought that perhaps it would be a good idea to have a different technique for measuring. We'll use an ordinary instrument with ultraviolet photographic enulsion, take both pictures and spectra. We submitted our proposal to NASA to use the X-15 for ultraviolet measurements. And the first test was made with a small photometer that was made exactly the same dimensions as their movie camera, and could replace the movie cameras in the bubbles inside. Today I was worried: there is something wrong with the X-15 down there in the exhibit. It doesn't have the bubbles on it where the cameras go. These are foreward and aft-looking just behind the instrument elevator, which is the section that is right behind the pilot's compartment. We flew our photometers in several X-15 flights by just replacing one of the cameras. It measured a blue wavelength and an ultraviolet wavelength. It was a beam splitter, essentially; an interference filter that reflected light in the visual through a blue filter, and transmitted the ultraviolet light to two separate photomultipliers.

DeVorkin:

Were these behind little glass bubbles, or were they exposed near space? They must have been covered up again as it landed.

Code:

Well, wait a minute now. The Iconel Bubbles protected them, and more or less protected areo-dynamically, too. There is a quartz window.

DeVorkin:

That makes sense.

DeVorkin:

Let me ask about the process of your proposal just very briefly. You must have made this proposal directly to Nancy Roman at NASA? The Astronomy Group?

Code:

The Astronomy Group, no

DeVorkin:

Or the "Office," as it was called.

Code:

I think we have to back up slightly. Right after NASA was created, there was a panel to consider telescopes. And in particular, the idea was single platform for all optical observations. And can we get all these experimenters together and agree on a particular platform? The person who was in charge of that effort was Garry Shilling. He didn't last very long. Nancy Roman came over from NRL and got involved. But Shilling was the one who headed that up.

The conclusions of those meetings were that they wanted to go ahead and you sent in sort of a one-page letter, and they could start some funding for study. That was money on the order of $10,000 which was quite a bit more than $10,000 is nowadays. And I think that was in the late fall 1958. It would be sometime in the spring then that they would start to get the results of studies. And there were quite a few meetings. It was after we had this initial funding that we then put in a proposal, and that proposal, the first one for the X-l5, was perhaps three or four pages. It was dittoed. The person who was in charge of that was Ernie Ott.

DeVorkin:

The person in charge was in NASA?

Code:

Yes.

DeVorkin:

First of all, do you think you have copies of those proposals?

Code:

Oh, yes.

DeVorkin:

Great. That's number one. Number two is when you proposed the X-15, was there any resistance to its use, or was it freely available, as far as you knew?

Code:

I think it took a little bit of maneuvering on the part of Ernie Ott to talk the high speed flight center into considering this. They were a bit leery. The X-15 was a research plane, where altitude and mach number were the important things and it hadn't flown yet. Meanwhile, we had completed our study, completed it as far it ever went, of over a 100-pound satellite.

DeVorkin:

Yes, this was with your balloon work and things like that?

Code:

Some of our laboratory experiments helped in defining and building some electronic circuits.

DeVorkin:

Before you finish with that, Schwarzschild was coming out to your part of the world with his Stratoscope I at that time. He had, of course, the same sort of design of suspending a 12-inch telescope from a balloon, pointing it at the sun, and keeping it locked on the sun. What contact did you have with him and the work that he did?

Code:

Only being very interested in his activities and results. But I hadn't thought of that as any kind of prototype, or something similar, because I think that we were thinking that what hadn't been done was measurements in the ultraviolet of stars, where we were concentrating the optical components in the photomultipliers. We thought the other part was something somehow could be done, and really the science part of it was the that detectors and filter development and such.

Sometime in the spring of 1959, I guess it was, the concept for the single platform came out of an orbiting astronomical observatory concept. This would be a satellite, and its payload would be some 2,000 pounds of telescopes and could be about a meter in diameter. And here we had this little 100-pound 10-inch telescope (laughs) or something of that nature. I think it was about 10 inches; I would have to look at the drawings. Well, that looked like a pretty big spacecraft, especially after you throw away all the satellite part that we had in our proposal. So what we did basically was cluster a whole bunch of these and fill up a lot of this space.

DeVorkin:

Let me go back again. In the first program development that Shilling was involved in, as I take it, and certainly some of the others, they envisioned one great big platform to do everything.

Code:

Yes.

DeVorkin:

Solar telescopes, stellar telescopes, the whole bit. I know that some astronomers didn't care for that very much, and they wanted single purpose instruments. This was before the OSO and OAO series were delineated. Could you review in your mind for us what the progression of events was that you were involved in the decision-making process? Who argued for that single multipurpose platform and how did it develop into the single-purpose multi-satellite mode ?

Code:

I think that there wasn't any schism, except for the solar people. Everyone else, even with some thoughts of x-ray astronomy, said sure. But Leo Goldberg said that no, he couldn't go along with that. The requirements really are different. I can not think now what the differences were. I don't remember what the precise arguments were. John Lindsay may have been brought in for a study of the solar requirements, but he was certainly the biggest prime mover and spokesman for a solar dedicated OSO, and brought that about. It was Leo Goldberg who first made the split and said that a single platform won't do for all branches of astronomy, and decided on the separate effort facility. But I think everything else for quite awhile stayed together with the single platform. Now, I don't recall the entrance of George Clark and Krauschar's gamma ray Explorer; but it didn't come the route of astronomy to start with.

DeVorkin:

Right. That was Explorer II. Then within the astronomical community, other than Leo Goldberg and John Lindsay, most of the people you were in contact with, as your recollection has it, especially yourself, saw no immediate problem with a multifunction single platform?

Code:

Well, yes, in terms of our concept; but as I said, we had this little thing, and there they were talking about a big telescope. So one of the things they did was say, well, Fred Whipple had proposed the UV television system, and his cameras were pretty small so NASA said: "Let's cluster all of your telescopes and his together in a single payload." And we started to talk about this. How do you make this? If you have a single can that contains instruments from two different organizations, how do you work out all the interfaces if you have to bolt one piece to another? Moreover, it still didn't work right, because even though you covered the area, they were short. They didn't fill up the length of the spacecraft. And so I said: "Well, why can't you poke a hole in the other end and separate us, make the interface a bulkhead in the middle; and one experiment looks out one way and the other experiment looks out the way other way; and then there is a clear separation." We just provide two separate cans, again, a slit end. The response was that that's impossible.

DeVorkin:

Who responded?

Code:

It was whomever the project managers and engineers involved in this effort were at Goddard, which I suppose was located by then at the Naval Ordnance Station.

DeVorkin:

Yes. That could have been Kupperian?

Code:

Kupperian was certainly highly involved from the beginning; but no, I mean it was from the engineering side. Then at the next meeting we went to a couple of weeks later. It was an accomplished fact. We had never even said it twice, and that's the way it was. It was going to be a double-ended spacecraft.

DeVorkin:

(laugh). Now let me get a few things in context here. What you are talking about eventually came to be know as OAO 2.

Code:

That's right.

DeVorkin:

But there was another group that was designing for OAO 1. Is this correct?

Code:

No.

DeVorkin:

But I thought you also had a flight on OAO 1?

Code:

Well it was all OAO-A until it got up.

DeVorkin:

A good point, yes. Of course

Code:

And this one I'm describing is OAO-A and how it became one and two, I'll get to in a moment.

DeVorkin:

Right. Were there not other competing interests?

Code:

Yes there were High Dispersion Spectroscopy; Lyman Spitzer with about a one-meter telescope. And that would be one of the OAO's. The Kupperian crew had their medium resolution spectroscpy experiment. Well, each of these was successively more difficult, particularly in terms of pointing. The Smithsonian-Wisconsin experiments required the least pointing accuracy; whereas, the Princeton High Resolution Spectrograph required the highest pointing accuracy. So it wouldn't be able to come along as rapidly. It was a bigger instrument, and both of these others would fill an entire payload. So they were thought of as three separate payloads, and they ran in order, A, B, C,. The Smithsonian-Wisconsin experiments were A, which became the Goddard payload; the Goddard experiment package was B; and the Princeton PEP, (Princeton Experiment Package) was C.

And C is the one that ultimately became Copernicus. Now, to follow this along, what happened with OAO-A was that as it got closer to launch, Smithsonian was behind schedule, primarily because of the Uvicons, because it was really beyond the state of the art television camera, and they were having trouble, or General Electric was having trouble in developing. So then they wouldn't be able to make the launch date. And so NASA collected experiments — they now had an "A-1" and "A-2". And "A-1" would be the Wisconsin experiment, because that was finished and ready to fly. And looking out the other way would be a set of x-ray experiments. Of these experiments; one was provided by Lockheed, and P.C. Fisher was the principal investigator. The other was a Goddard x-ray experiment with Ken Frost, Clark, and Krauschar. So they produced these. All of these were selected because they were essentially rocket hardware that already existed, so they could put together a quick x-ray payload. And so, A-1 was launched. It lasted about three days I guess. But a problem developed after a day. This was the heating up of one of the batteries. It kept heating up, and then strings of diodes started dropping out in the command matrix, and some things were failing in the power supply. It probably all had to do with the power supply regulator.

No experiments were ever turned on. Probably, they opened things up and started going too soon in terms of outgasing. And the first event happend on something like the second orbit. They turned on the star tracker. They got star tracker arcing, and that was probably what started things degrading. So, because of this — getting too much power for the solar panels — NASA Headquarters sort of took over. The project manager wasn't a tough enough character, and so everybody had their own ideas on how to do it. The project was plodding along with various tests and recovery plans, and during these three days some people worked on it. We were able to do some clever things, like manually load the memory from a remote station in Australia by radio.

Telling the auroral tracking station what switches to throw in the computer to uplink a command. At any rate, the Headquarters people decided to put it into a tumble, and then the solar panels would be always oriented toward the sun, and we could lower things that way. Code—37 They forced their opinions onto the project; and they put it into a tumble, and sometime shortly after that the whole thing exploded. And later on separate pieces were tracked. The battery blew up. So that was the end of OAO-1.

DeVorkin:

First of all, during these three days, where were you? You must have been at Goddard?

Code:

Yes, we were all there as experimenters.

DeVorkin:

Was there any function for you?

Code:

No function, in the emergency, except for trying to say: "Why don't you turn this on, even if we are tumbling around, we can get something and you can find out if the experiments work and so on." But they never succeeded in getting any instruments turned on.

DeVorkin:

Could you name some of the Goddard people? Who was the project manager, who was replaced? Who at NASA Headquarters was the strong person coming in?

Code:

No, I can't. I might in 10 minutes or half an hour, think of someone.

DeVorkin:

Okay, That's fine. Yes, you know that you will be getting a transcript of this, and there will be more time then to fill in some of the names. Or you could direct me to some places like this. Let's backtrack a little bit and talk about the particular instruments, and how you decided to put these particular instruments in; also about the staff that had been building up at Wisconsin. What kind of people did you attract? Did you have problems attracting people in this very first work? Let's first take the staff. How did you go about getting staff?

Code:

To start with, we have never been very big and we used graduate students. It was an electrical engineer, John McNall, who was interested in astronomy. He had just gotten his Ph.D. at that time. He was with us for a good number of years, and was the electronics and computer expert for the lab. For stucture, thermal, and initial studies we got help from the Solar Energy Lab, which is part of the Engineering Experimental Station, Engineering Extension. They knew about the properties of surface materials. We hired one machinist technician type to start with. And the nucleus was just the Astronomy Department faculty members, graduate students, a secretary and a draftsperson, a draftsman and a machinist, and an electrical engineer. That was about it.

DeVorkin:

As far as the graduate students are concerned, did you have any difficulty getting them interested in the projects?

Code:

None whatsoever. Then when we finally got into the OAO program, we had to start making hardware. We had, in addition to more students, three electronic technicians and two machinists; and then we started with programmers. At one time we had five programmers, I guess; and two systems people.

DeVorkin:

I do have the impression that, at least, from talking with a few people who were with you, that a number of the graduate students like C.R. O'Dell worked with you for awhile, but then left and went back into ground-based astronomy.

Code:

That's correct. They had some specific problem that they were supposed to work on, so their participation wasn't open-ended anyway. They would ultimately have to work on a research thesis, and that isn't to be found in the instrument development stage. You have to wait until you can really get data. Now one graduate student did, during this period, do research with X-15 data, and another with sounding rocket data that we had.

DeVorkin:

Who were they?

Code:

Martin Burkhead, who is now at Indiana, did work on the X-15 data, and also made ground-based observations that complemented that. (Pause)

DeVorkin:

We just had a pause. This is a peripheral break, also. You just mentioned a term I'm not familiar with.

Code:

I called it Grand Bang instead of Big Bang. A Big Bang universe starts back a few milliseconds, or microseconds and expands, and many of the things we can understand in terms of a Big Bang universe. It has a number of problems: why is it so isotropic, or why is the background radiation so isotropic; and yet you've got the condensation of galaxies. There is what's called the flatness problem, which some people put in terms of where is the missing mass? And others say: look, it's so close to being flat today. Qo is between 5 and 1/10, or something of that sort, and that's practically unity. Why is the universe so flat? (laugh). There is the horizon problem which is related to the isotropic problem namely, how does the universe know to be 3°. After all, photons that are coming to you from one direction in the sky, and from the opposite direction, are just arriving here for the first time. The matter has never been in contact, so the causal horizon is much smaller than the observed universe.

The causal horizon at the time of the decoupling of the radiation produced the background radiation. Now then, the other problems. Well, the most fundamental problem is: why is there a universe at all? The baryons and antibaryons should have been equally probable, and they wipe each other out. But then there are some simpler problems. If all the elements were brewed in stars, except the original hydrogen and helium made early in the Big Bang, how come we don't see any of the primordial stuff around in the universe? Certainly, it hasn't all been cycled through stars. And there are a few other little problems. Almost all of these problems are taken care of in the Grand Bang by invoking the grand unification theories of high-energy physics. Then, you can start talking about the universe, at times less than what is called the Planck Time, 10-43 seconds. So the universe has been expanding like an ordinary expanding universe for the first 10-43 seconds.

DeVorkin:

Not a very long time.

Code:

No. During that time the temperature and density is very high. Densities, for example, are down to about 10 99 grams/cubic cm. when you get to 10-43 seconds. And all particles exist on equal footing. All of the coupling constants are the same. All the gluons that are the binding for the interactions are all the same. They are all zero mass, and and everything is nice about the universe. Then you get down to a low temperature like 1014 gigavolts or so, that occurs at 10-43 seconds or thereabouts. Then the universe starts breaking symmetries. This is when the different gluons begin to take on mass. You get different coupling constants when you separate out the different forces: gravity, strong forces, weak and electromagnetic forces.

A Grand unificaton theory would include all of these. There is not a really satisfactory one that includes gravity at the present time. And gravitions separated out in this early phase. But this all goes on. It doesn't happen instantly. (laughs). The universe supercools. Breaking these symmetries is like the freezing out of a fluid; it becomes supercooled. So during the supercooling stage, the gas cools but the vacuum, from which all these particles were produced, you know, the underlying fields and field theory still has this very high energy of these 1014 gigavolts. The matter begins to cool and gets low energy, and if you look at the field equations for expansion of the universe, the effect of this high energy in the vacuum is the same as a cosmological constant. The solution becomes the same as a Steady State universe. That is, the universe expands exponentially, as it does in the Steady State. Initially, if you have radiation or relativistic particles, the radius expands as the time to the one-half power. If you have ordinary matter, it expands as the time to three-halves power in a flat universe.

But if you have this large cosmological constant, then it goes exponentially. And so the universe expands for the length of time it takes before all this stuff suddenly crystallizes, and supercools for awhile. How long can it supercool? That apparently takes you to about 10-33 seconds. During this time the universe expands by many orders of magnitude. It expands e-folding — it expands e100 power during that time. Then when the Grand Unification is, finished, and particles are separated out when it freezes out the way it is today — all that energy is released to go back into the matter. And it goes back up to 1014 gigavolts, and you've got a brand new universe essentially starting off, except now it has things like protons and pions. Particles that are more like you have in high-energy accelerators and such. This start solves a lot of problems, because first of all, the universe is practically flat. If you imagine a balloon expanding by a factor of e100, and then you start off on a part of the surface of the balloon. The part that you can see for quite awhile is pretty flat.

Also, part of the universe is causally connected to the part over which light can cover, which today is something like three times the velocity of light times the age of the universe. But that's becasue it's also expanding. All right, during this expansion phase, light has moved out, but also any particular coordinate has been expanded by a great deal. So all of this part of the universe that was connected causally corresponds to a pretty big part of this whole sphere. This is called the inflationary stage. And then you are starting out all over again. (laugh). And even the part of the universe that we see today, because the expansion afterwards is small compared to this initial inflation; that is still, 100 times smaller than the boundary of this, causally connected.

And so at one time everything knew about everything else within the observable universe, and quite a bit beyond, so the universe is flat, and there is a reason for it to be isotropic. And then in the scenario it also follows that protons have a finite lifetime. That also means that neutrinos have a finite mass, and a lot of the missing mass is neutrinos. That also helps to explain how you made galaxies in the first place. Because the fluctuations in matter get damped out, and they always remain very small during most of this stage. But things like neutrinos don't get damped out. They build up to be fluctuations.

When the radiaton decouples producing the three degree background, the universe becomes the matter universe. That's the only thing the photons were interacting with. It is fairly smooth, so that's smooth. As soon as it is decoupled, then there is no longer damping in the matter part. The universe is already highly clumpled in neutrinos. Most of the mass of the universe is clumped, and it's just the matter part that has been smooth. Well, of course, it's going to be drawn into these clumps, and the amplitudes build up big so you can build galaxies. They solve most of the problems by the events that happened in the first 10-33 seconds using the Grand Unification theory. That's why I called it the Grand Bang.

DeVorkin:

Some say you don't need rotation or anything like that to produce galaxies?

Code:

No, there are a couple of problems. One of the main problems with this inflationary stage is this crystallization process, the way crystallization and supercooling occur you get nuclei, and then the area expands, so you get bubbles. But the universe is expanding so fast these bubbles can't overlap (chuckles) and they talk about it not exciting the inflationary stage very gracefully. It still is going to be clumped, and they have to work on that.

DeVorkin:

Who coined the term 'Grand Bang? Was that yours?

Code:

Oh, I'm sure it isn't mine. I'm sure I heard other people say it. It just sort of naturally follows, though.

DeVorkin:

Are you thinking of this in the context of an exhibit?

Code:

Well, I had often thought about the original Big Bang scenario, that you could do it at several levels. One is just a set of drawings. You see these hyperons at this high density, and it just tells you what goes on there. And you follow in time and show pictures at the time you make helium synthesis, and at the time the radiation field decouples. And you try to explain these. Then you can think of it as a film strip, or finally as a video cassette describing the creation and evolution of the universe.

DeVorkin:

We gave it a try. We thought about it, but it was tough, in terms of making it something that the public, we thought, could have comprehend in a reasonable amount of time.

DeVorkin:

That certainly is an interesting scenario, and it makes me realize that we haven't talked too much about the science that you have done, especially in the 1950's leading up to your return to Wisconsin. But I do want to get through OAO, and certainly to the science that you did do with the Wisconsin experiment package. We finished off at the point of the break talking about the X-15 and sounding rocket work that was being done as part of your preliminary testing and design period. You mentioned Martin Burkhead, but you don't mention the second name of the student or person working with you. Was it John McNall?

Code:

No. Charles C.F. Lillie did a thesis with rocket measurements. In the X-15 program we were actually working towards a pointable system, and we built with a subcontract to Astronautics Corporation of America, which is located in Milwaukee, which was a small company just getting started, and had been a splinter group from Oster Motors.

DeVorkin:

It's a big title, Astronautics Corporation.

Code:

Well, that's the title they started with. We were about the first job they had.

DeVorkin:

Did you consider them because they were local, opposed to Ball Brothers?

Code:

That was important. We did get some proposals, and cost was important, too. So they built two stabilized platforms that were the outer dimensions of what's called the instrument elevator in the X-l5, which is roughly a one meter by one meter by one meter cube, or maybe one and one-half meters deep. And if you take a look at the X-15, you see a hatch essentially right behind the pilot's compartment. That's where all the instrumentation is put in the racks in there, and then it's lowered in. Well, instead, we put this gyro system in and in the center of the gyro system there was a post that contained a star tracker, and then mounted on this post would be our cameras. This would replace the instrument elevator, and there would be doors on the hatch that could be opened in flight. After getting into ballistic the pilot would then orient the X-l5 so that the hatch was more or less pointing at the area of the sky we wanted to pick up.

Then the gyros were uncaged in the gimbal system, and the star tracker would lock on a star. If it failed that then after a certain period of time it would just turn that off and remain stable on the gyro, so we would get a picture of some part of the sky. The pilot was really, in a sense, flying the dome then. He had to just keep the shutters from going over the end of the telescope. The way that the pilot knew the orientation was that we would put in a bias on the attitude fly ball. And the way you fly an aircraft like this is to keep all these needles zeroed! (laugh). That's the task, and he'd throw a switch, and the biases came in. The fly balls started to move, and he would follow that, and put the X-15 in that attitude. Of course a ballistic flight could be any attitude.

DeVorkin:

You were aiming for particular stars?

Code:

Yes, we would want to take a photograph of the Constellation of Orion. Later on, we put a spectrograph down in this pipe and we got spectra.

DeVorkin:

Did you actually get a photograph of Orion in ultraviolet, and any spectra?

Code:

We never got a photograph of Orion. We did manage to determine with both these photometers and with a stable platform that: first of all, it was not true that there were big halos around the bright stars in the ultraviolet, nor that the energy flux was very different from model prediction. We did get the first measurement of a later type star, Capella. Lowell Dougherty is the man who worked on the X-15 at that stage. Earlier when we were flying cameras in the bubble, in the visual range, Northrop used the data for sky brightness measurements. And then Chuck Lillie was the one who took the ultraviolet data as well. There was sky brightness, and they also had a rocket flight they used. This was measurements of sky brightness without airglow and of zodiac light and galactic diffuse light.

DeVorkin:

Yes. These rockets experiments were not pointed then?

Code:

You knew where they were pointed after the fact, but the cameras were just fixed with respect to an X-15.

DeVorkin:

Yes, I meant on the sounding rockets.

Code:

The sounding rockets were spinning. The X-15 was an interesting adventure, because here there was a man in the loop who had to do this task.

DeVorkin:

Any recognizeable names of the X-15 pilots?

Code:

Oh sure. The chief test pilot cracked up in a chase plane.

DeVorkin:

Crossfield?

Code:

Scotty Crossfield actually worked for North American. He was a North American test pilot but once he got turned over to NASA ... Neil Armstrong was one of them too. He only flew it once. He was the youngest of the test pilots out there. He had already applied to be an astronaut at the time that he flew the experiment. John McKay was another one. And the aircraft, of course, had to be modified to put this hatch in, and prior to that we were flying just these cameras in a bubble. On one of the flights the flight was aborted. There are a number of dry lakes. You drop from a B-52 up in Washington, and then you shoot up above the atmosphere and then glide down to Edwards Air Force Base, but there are alternate landing sites. After being dropped from the B-52 in this case there was some malfunction, so McKay had to land at the very first of these alternate dry lakes.

And he wasn't able to dump all the fuel, so landed with weight in there. It comes down, you know, and skids on these big metal skis; and then after awhile the nose hits and bounces a few times. When it did that, the nose wheel simply dug into the sand, and the X-15 flipped over. He jettisoned the canopy, and the very highest thing then, the first thing that hit, actually was our camera. We've still got it, with just a small gouge out of it; but it survived and worked afterwards. And then the next thing that might have hit was McKay's head. And when they picked him up, they said if he had been an inch taller, he would have gotten smashed. When they got him back from the hospital, he was about two inches shorter that he used to be.

DeVorkin:

Why?

Code:

From this impact, compression of spine, and he was built like a football center, real massive thick neck, and probably some smaller people wouldn't have survived. At any rate, this plane then had to have a body job after the crash it was the one that was modified. They put the hatch in, and they tried one other thing. They lengthened the fuselage a little bit to hold more fuel for getting a little more thrust, and getting to higher Mach. That aircraft never performed as well. We never got to the altitudes that we had gotten to with the earlier one with the bubbles. Nevertheless, we did get the gimbal system in, and had a number of flights and got some astronomical data. But it was fun working with the test pilots. I had a lot of fun when we first put in our modifications, the bias in the flyball and such, flying this on the simulator. I "cracked up" the X-15 a few times when I first started. But this is quite a different task than flying in ballistic flight; and it was something that when you change it from how pilots are used to, it was, I think, probably easier for me to handle the job than it was the test pilots, to start with. They had too much built in already.

DeVorkin:

Yes, I understand. Let me get it straight about the instrumentation for the X-15. Was the data telemetered to ground? Was it photographic?

Code:

In the case of the photometers, it was stored on board in a tape recorder. In the case of the cameras, and the spectrograph, it was photographic.

DeVorkin:

Is there a publication we can point to in your vita?

Code:

No, I don't think so. All the publications are just reports — Lowell Dougherty's paper, the Northrop publication, Martin Burkhead, and students who worked on it.

DeVorkin:

Would you have copies of these?

Code:

I could produce some papers on the results of the X-15.

DeVorkin:

I would be interested in a general description of what was going on. So then, what was done with sounding rockets, in particular?

Code:

Our very first sounding rocket was to test the photometer assemblies that we were using in OAO. But they are so far in structure from what you put in a sounding rocket payload that by the time you modify them to put them in a sounding rocket, you really weren't testing the OAO instrumentation. In several of our flights, the payloads have been ultraviolet photometers and directed at measurements of the absolute energy distributions of stars. The advantage is that the rocket payload is small. We did the calibration using synchrotron radiation from the synchrotron storage ring at Stoughton, Wisconsin, Physical Science Laboratory. You can make an absolute calibration. It is possible. What you have to know is the diameter of the ring, strength of the magnetic field, mass of the electron, the charge of the electron, and the velocity of light. It is actually possible to see a single electron with the naked eyeball. See the synchrotron radiation from one electron.

DeVorkin:

You mean the scintillation, as it enters your eye? Or as it hits the detector?

Code:

No, no, just as it's going around the track. Each time it comes around you can see it.

DeVorkin:

Bremsstrahlung?

Code:

Synchrotron radiation is relativistic Bremsstrahlung. You can see that from one electron at 50 MeV, or something of that sort because, with a storage ring people have tried this. You can get rid of the electron by just deflecting it so it passes over the window instead, you see. So you have somebody look in and ask: do you see anything? And you can move it out and see if he still thinks he sees it, and experiment that way. You’ll find that the individuals knows. Now, what we would do is have very low beam currents, get them down to the order, say of 100 electrons in the beam. And then reduce the RF power, which makes up for the losses in the beam; so you begin to lose electrons. They hit the wall and such. The stored beam will be K.

You are now looking at it with a photometer, and this is down to like 100. You can see the steps; it loses one: 99, 98, so you count the electrons on down until they disappear in the photometer. So you have an absolute calibration, and know exactly how many electrons by actually counting them. And then from those fundamental constants, you are able to compute the radiation, so it doesn't have anything to do with the temperature scale, or Boltzman's constant. It's quite an independent way of doing the calibration. You can check it in terms of polarization, also beam width. You calculate it with a theory, then the angular width should be such and such, so you measure across, map out the beam, and see if that follows the theory, too.

DeVorkin:

Did you come up with this calibration procedure yourself, or did someone suggest it to you, a friend in high-energy physics, possibly?

Code:

Oh, I'm sure that I didn't just think of it, and I don't know how it originated. People talked about the use of synchrotron radiation for calibration. We had the storage ring available, so I guess we thought "why don't we do that?" Then we started to get into it, I think that it was Tim Fairchild in our lab who thought of the idea to count the electrons. If you're going to calculate you can calculate the spectral distribution but the actual total flux, if you want to get that, you have to know what the beam current is. How accurately can you measure the beam current and so on. So I guess when we were kicking that around we said; "well, it's so bright, we don't want the usual beams. We want it way down, and so why can't we just count the electrons, and we could (laugh)." So, the instruments that actually flew in a rocket could be calibrated at the synchrotron facility.

You could shine in light, and then you don't have a whole bunch of steps in this calibration, as many calibrations do. You don't calibrate detectors against thermocouples, or check this against a black body. And the spectral distribution is just about the same shape as an early B star in the range we are using so it has the right spectral distribution, too. Whereas, any ultraviolet calibration with any kind of a black body source or something is impossible, because the sources aren't hot enough. That was one of the kind of experiments we carried out with rockets. More recently we have been trying to do spectropolarimetry with a rocket although you can only do the brightest stars. It's an extension of this rocket program that is the present Shuttle payload OSS-3, that we have. That is the reason I was here today.

DeVorkin:

The series of experiments then that you were carrying out were all directed for giving you experience on OAO I-A, as it was designated?

Code:

That's the rationale for NASA paying for it, but of course they were directed at learning about the ultraviolet radiation from stars.

DeVorkin:

Yes. You always maintained that scientific interest was your driving element in all of this activity?

Code:

Yes, in fact, we were never directly funded for the sounding rocket tests for OAO. The contract said something like "ultraviolet studies of stars and galaxies." That was the title of the contract that we had for years, in which OAO was funded in sounding rocket tests. Then it continued on to support rocket flights after OAO for awhile.

DeVorkin:

As you then developed instrumentation for OAO, you must have made a lot of trips to Goddard to talk to the people about integrating them into a spacecraft and that sort of thing. What was your general perception of NASA, how it was developing, and the kinds of people who were being drawn into Goddard to work with you from inside the Government?

Code:

They were intelligent, capable people just like we were. No one had experience in doing this kind of thing before. The scientists and some of the engineers came from NRL, and did things on a fairly informal basis. Initially there were some problems with the contract, because it was copied from a Defense Department contract for industry, and as a university we couldn't comply with it. In fact, some things were even in violation of Wisconsin State law! (chuckle). The Government has worked this out now, but in the State of Wisconsin you couldn't pay for anything until you had it. And the Government wouldn't give any money until you had it.

DeVorkin:

That must have caused some problems.

Code:

But at any rate, we just said that the University is different, and you're not even paying our salary, you know. But that worked out. Now as far as working with Goddard — as I said earlier — Goddard was a Naval Ordinance Lab and there were green fields out at Greenbelt, and we saw them move in there, and saw them building up, and visited people. Things were much less bureauratic and relaxed. I don't think that today we could do a program like OAO. It would have been made a much more complicated big deal that it was. And many interfaces were driven by us, because we were further along in our experiment than anybody else, or the spacecraft itself. So when it came to what kind of bit structure, voltages cables or connectors were to be chosen, we said: “well, we would like it this way because we've already got it that way" and there wasn't any reason for making some different choice. So often we were the determinants for what Goddard and Princeton were going to have to do for their experiment when they got to that stage. And also, Smithsonian was a little behind.

DeVorkin:

Yes. Who actually built your cluster of instruments?

Code:

Our flight hardware was constructed by the Cooke Electric Company in Skokie, Illinois.

DeVorkin:

They acted as a subcontractor to the University of Wisconsin?

Code:

That's right, yes.

DeVorkin:

Did they do the optics as well as the flight hardware?

Code:

No, the optics were done by, I believe, Ferson Optical. And all the coatings of optics, all the detectors, mounting of detectors, all the filters were done in our lab, but they did the structure and testing. Part of Cooke was Inland Testing. They had the necessary vacuum tanks and shake tables and so on to provide testing.

DeVorkin:

What kind of company are they? What did they do before your contract?

Code:

They did a little bit of space work, retrieval systems for rockets. They were primarily a transformer company, in that most midwest electronics is very pedestrain, and midwest never made a big effort for either DoD or NASA contracts, because the kind of things that most companies in the Midwest made were things that everybody needed. They had a market and they weren't going to go into R&D and take chances.

DeVorkin:

Cooke evidently did. Did NASA send any kinds of visiting people to check Cooke out to see if they were capable of doing this work?

Code:

They did some. Oh, at that time Cooke had NASA contracts and NASA knew them. We had proposals that went out to bid, and we got proposals from Bendix, McDonald, TRW (but it wasn't TRW then), Texas Instruments, Astronautics Corporation of America, another small company in Milwaukee, and Cooke Electric. This other company in Milwaukee is now demised. I knew all the people; I can't remember the name of it. They were the low bidders, but we thought Cooke's was the overall best bid. It was really highly desirable to have a company that you could just jump in a car and go to, and that worked with you, rather than going off to St. Louis to McDonald, and have them just take it away from you. They would be working on something trying to solve a problem because we don't know enough to specify things that really weren't a problem.

Gee, we could have put down there a "hundredth" of an inch" instead of “one-ten-thousandth of an inch." "It doesn't really matter. I'm sorry you spent a month trying to solve the problem.„ But in the case of Cooke we were in contract with them every day and went down there and shuffled equipment back and forth. We made all the electronics they designed. We made bread boards ourself and tried them out to see how it worked and learned about it. So it was a close and successful collabration. They made three: there was an engineering model, a test model, and a flight model. And after the failure of OAO-1, the engineering model was used in A-2. Then we still had this test model, which is the one that is sitting out in the hall at Wisconsin right now.

DeVorkin:

What do you have out in the hall?

Code:

The entire payload, five telescopes in a big can, this high, this big around! (laughs).

DeVorkin:

Really!

Code:

It's exactly the same as the chunk that is in orbit.

DeVorkin:

It's actually real? I mean, you have optics and detectors inside?

Code:

Oh sure, everything is mounted. You could probably plug it in and make it work.

DeVorkin:

That's very interesting, considering my interest here.

Code:

Paul Hanle saw it sitting out in the hall. It looks like a great big black garbage can (laugh). It's not pretty.

DeVorkin:

But you can look into it and see that there's optical equipment?

Code:

You look down at the mirrors.

DeVorkin:

The central one is the 16-inch?

Code:

Yes, a 16-inch hole, then four 8-inch telescopes, and then slot collimators for the two spectrographs. Yes, you can look down and see all the optics.

DeVorkin:

Yes. We might talk about that sometime. What are your plans for that?

Code:

Oh, I think to put it in a museum is fine. Incidentally, about the two stabilized platforms that were built for the X-15. When NASA announced opportunities for the orbital test flights for the first Shuttle, we thought it would be a good idea to make some measurements of environment as far as it affects the ultraviolet. Is there an ultraviolet glow? What kind of contamination is put up in the Shuttle? So we proposed an experiment in which we would actually point at a star. So we're looking at a star, and then if material gets in the way, we see it fluctuate or we see flashes of airglow. So we needed a pointing system. We looked around. We thought about a pointing system, and we thought about these gimbal systems that we had made, and where are they now? We started to track them down. One of them was in New Jersey in the Signal Corps. Well, I can't think of it right now, but it was used for pointing an antenna. Because of the little gyros in the servo system, you can control them. And the other one, presumably — this what we found out; I haven't seen it — is in the Space Museum in Hunstville. Well., we could have gotten the one from the Air Force and used it to fly this payload if it had been accepted. But I thought it would really be great to take something out of a museum (laughs) and refly it.

DeVorkin:

Did you do that?

Code:

No, well, this wasn't one of the orbital test flight things that was approved, so we never got to the stage of getting the platform.

DeVorkin:

I see. So those platforms still exist.

Code:

Apparently so, yes.

DeVorkin:

And they could be classified as one stage in the evolution of pointing controls.

Code:

Yes.

DeVorkin:

What was their positional accuracy, to your recollection?

Code:

That was determined entirely by the gyros, which were integrating rate gyros, probably quiescent stabilities of 10 seconds of arc, maybe. We weren't interested in that kind of precision. If you got all the biases adjusted right in the integrating rate gyros, I think probably your noise might be at that level.

DeVorkin:

That was better than the pointing accuracy of the OAO. As I recall, the value was about one minute of arc.

Code:

Well in OAO, A-1 and A-2, the fundamental and really only reference were the gimbal star trackers. If you lost stability, then you had solar sensors and went back to the sun. The gyros were not high performance gyros at all. Well, let me see now, if I remember what was the limiting thing. The fine flywheels are probably good to a few hundredths of a second of arc. We did have motions with respect to the optical axis of our instruments of the order one to two minutes of arc. But these are long-term thermal distortions and that meant miscollimations also or star trackers. So you could get, when you had to switch star trackers, the spacecraft would jump by a minute of arc perhaps, because they are not all lined up. But the star trackers themselves were significantly better than that. The gyros weren't depended upon for any kind of stability, and they weren't very good. So I don't know what they're like. But in Copernicus they replaced the gyros, with high performance integrating rate gyros, and the gyro became the fundamental system, and the star trackers auxiliary or backup, really. That is so much easier to use. The OAO-A-1 spacecraft was in trouble if it wasn't observing. You had to have stars and star trackers locked onto some position. If it lost those, then it went into a tumble, and you then had to recover. The only way that pointing and selection of stars for star trackers got generated was through the software we had for our observing programs. So unless we were observing, there was no way to keep the spacecraft stable. So we had, for 50 months, a 24-hour-a-day task of generating the target lists, that part of the command memory load for the spacecraft. And so it kept us awfully busy.

DeVorkin:

Had you known this before launch? You must have known this with the A-1 system, too, as well as A-2?

Code:

We knew that was the way the system was, way the that it was our software that was required to determine the satellite's stability. We didn't recognize what a taskmaster that would be and how hard we had to work. We could never really get help, or train other people, because we were all so busy we couldn't take time out to train someone else. (laughs). From time to time the personnel switched, and we did bring in other people and train them, but it takes a long period of time. So all of us were intimately involved with the day-to-day control-room environment and running the spacecraft. That doesn't give you much time to think about the data.

DeVorkin:

The last thing maybe we should talk about today; how you felt when OAO A-1 failed, and what your plans for the future were? Who did you talk to? Did you get any advice from anybody?

Code:

I'm not sure I can answer all of that now. I would like to think back, because of course it was a really traumatic thing. Ted Houck, whom I mentioned earlier, was very heavily involved in it, and we worked together intimately. He never effectively recovered from that. He was never able to do any more work, and ultimately he died a few years ago, and it was primarily from alcholism. I think that these kinds of things have a lot of casualties, probably among projects, or, I can't name anyone, but probably divorces and things of this sort accompany programs; especially programs that end in some failure like this. Particularly now, if you're blamed and out of it, like some of the project people were after that failure. There is a big shake-up and new management, new people involved.

DeVorkin:

Well, what about Ted Houck? I mean, he was working with you. There was no evidence of failure of the experiment package itself?

Code:

No but so much of his effort and time went into it, and it came to naught, and he participated in the second OAO; but he was never as capable and enthusiastic after the failure of the first one.

DeVorkin:

How about yourself? How did you feel?

Code:

I really felt quite bad. I couldn't quite believe it. I took leave and went to Kitt Peak for a year. And I just got back into things, and I worked on the next one. This is a curious thing that happens, also.

DeVorkin:

Yes. Tell me that, and then I what to know how long it was before you knew you were going to fly again.

Code:

I would have to look that up. I don’t think it was terribly long.

DeVorkin:

Okay. Was it while you were at Kitt Peak, or before you went to Kitt Peak?

Code:

Oh, I think even before. I think we knew almost immediately — wait a minute — we already knew. This is what happened: I told you Smithsonian wasn’t ready, so they got these x-ray experiments for A-i, and they were going to have an A-2. And A-2 would be Smithsonian, and they were to use our engineering model for the other end.

DeVorkin:

So you were going to fly twice.

Code:

So we already knew that we were going to fly. We didn’t have that to worry about.

DeVorkin:

What did the x-ray guys do, who had scrambled to get on A-i, and then got bumped? Was there any ill feeling there, anything you were in contact with?

Code:

I think they had high hopes and felt pretty bad about it, but it had not occupied much of their time. And they could get on back to the plans they had before they had been given this extra opportunity.

DeVorkin:

You had been spending four or five years of your time.

Code:

Yes.

DeVorkin:

What was the curious thing that happend that you mentioned?

Code:

This was more general. You get into these things because of your scientific programs, kinds of observations, things you would like to learn. In fact, today, that is an important part of a proposal, and in selling the program. Then CodeA82O93O -49- as you get started in it, you become interested in the instrumentation. And learning and studying how a servo system might work is sort of challenging, and is as interesting as, “why is grass green?” or something of this sort. Whether it’s a man-made or nature-made system, you can become fascinated. And that’s why people who are physical scientists can get trapped into engineering aspects, just as they get trapped into computers. So you go through all of this, and then as you get close to launch, you almost suddenly realize, hey, you can do science with this thing! (laugh). You start to rethink why you did it in the first place. I mean, it comes as a surprise and a bit of an excitement that, here, this thing that has been constructed, look what I can do with it now. You get back to where you started.

DeVorkin:

Were you getting that feeling just prior to the launch of A-l?

Code:

Yes, sure.

DeVorkin:

And A-2, I take it.

Code:

Right.

DeVorkin:

At Kitt Peak, the Space Division at Kitt Peak was still active when you were there.

Code:

Yes, it was.

DeVorkin:

Did you have any contact with them?

Code:

Oh yes, I was quite involved actually with the creation of the Space Division and I was the one who talked Joe Chamberlin into taking the job. But it started because of Aden Meinel’s interest. Aden Meinel was the first director of Kitt Peak, and he was approached by the Huntsville people — Stuhlinger and Von Braun and so on —to consider a big national telescope, something at least as big as the 200-inch, that you could launch with a NOVA.

DeVorkin:

The grand orbiting telescope, the ‘GOT’ or something.

Code:

Yes. And so Aden wanted to do this. I was the Chairman of the Scientific Committee at Kitt Peak at the time, and I thought it was a great idea. I thought, in general, I mean if the director and staff want to do something, then fine. They ought to be allowed to do it. If there isn’t enthusiasm in a staff about doing something, a board of directors shouldn’t superimpose the thing. So at any rate the AURA board voted, “yes, we should have a national space program, and a national observatory, as well as a national ground-based observatory.” And Aden started on this. He attended meetings of OAO, and also as we got into Large Space Telescope with Lyman Spitzer, myself and others were involved in this.

DeVorkin:

You were at Kitt Peak, 1964-65, 1965-66?

Code:

I don’t know just how it works out. CodeA82O93O -50-

DeVorkin:

This was already afier the Iowa summer study in 1962?

Code:

Yes.

DeVorkin:

Did you attend that summer study?

Code:

No I did not.

DeVorkin:

I didn’t see your name. So, was this your first contact with the idea of a large orbiting telescope.

Code:

Oh no, that part occurred much before.

DeVorkin:

That’s right. Meinel was director earlier.

Code:

Meinel was the first director. Nick Mayall was director when I was at Kitt Peak. Mayall was also an attendee at the Iowa study, and also in the Star report — what was that?

DeVorkin:

Star, that sounds familiar.

Code:

At the time that I was talking about the large telescope there was a paper that I had that came from a symposium at the American Astronomical Society meeting on the use of space.

DeVorkin:

That’s the conference?

Code:

Yes. Well, this paper here: Stellar Astronomy from a Space Vehicle, I had written first as part of a proposal that Aden Meinel submitted to NSF for a large telescope.

DeVorkin:

So that was two years before the Iowa study?

Code:

Yes.

DeVorkin:

Here’s the article. That’s the one we haven’t talked about that yet.

Code:

Yes. Okay, you see, just the very last paragraph talks about it.

DeVorkin:

Okay, page 284: “Longer range plans are being undertaken by AURA, directed toward a versatile precision telescope of large aperture, placed in a 24-hour orbit. Such an instrument would be capable of carrying out some of the more difficult and advanced research problems, and most likely following up the new and unexpected encounter in our first probes in extraterrestrial astronomy.” This didn’t refer to OAO.

Code:

No, no, that refers to the Kitt Peak space program.

DeVorkin:

Okay, which included a large 200-inch-class telescope.

Code:

AURA actually got a contract from NSF to start this study. There was an interagency meeting, in which it was agreed that after they got to the development and launch phase, that NASA would fund it.

DeVorkin:

Your actual visits to Kitt Peak were much later, 1967 and 1969.

Code:

Yes. This is much earlier.

DeVorkin:

Oh, so your getting involved in the Kitt Peak Space Divison was while you were at Wisconsin?

Code:

Oh sure, right. I was a member of the AURA board from the very beginning. And I was the chairman of what was called the Scientific Committee at the time that Aden Meinel wanted to do this. By this time there was a Space Divison that had been in existence for awhile with Joe Chamberlin as the director, and we concentrated primarily on rocket flights, although they did have some proposals for small Explorer satellites. There was a change in philosophy after Aden left. No longer was it dedicated to a large orbiting telescope.

DeVorkin:

Yes, I understand. But that’s an interesting interlude that I wasn’t aware of, and it’s not presently discussed in any of the short histories that are coming out. And I would like to find out more about it.

Code:

Okay, I’ve got copies of the proposals and other material on that stage.

DeVorkin:

Well, it’s about time to finish up, so for next time then, we should discuss your preparations for the successful flight and the science that you did with it; the reception of the astronomical community of that science. We should also in a little broader view talk about the science that you were doing and what you saw was going to be your participation in space astronomy after the OAO series, what you would look forward to after that. Is that a reasonable direction to go in?

Code:

I think so.

DeVorkin:

That you very much.

Session I | Session II