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Interview with Dr. George Abell By Spencer Weart At University of California, Los Angeles, CA June 10, 1975

Transcript

Weart:

The standard thing we do is, I’ll take it out and have the secretary transcribe it. It will go in our files. But nobody will quote it for publication while you’re alive without checking with you first.

Abell:

Well, that’s all right, I’m sure — just having an informal conversation.

Weart:

That’s right. If we were to have a formal oral history type interview, it would be a very different kind of arrangement. You were saying that you felt just about everything had come from some instrumental breakthrough or experimental breakthrough.

Abell:

I think that’s correct. What we’ve witnessed since World War II is almost a revolution in astrophysics, and it’s come about, I think, a number of ways, because of instrumental and experimental breakthroughs, new techniques, and new possibilities for observing in new wavelengths. Let’s take some examples. The development of radio-astronomy, of course, was initially an engineering development, as the techniques were developed. And at one time, just after the war, there was a field called radio astronomy. I think now there is no longer a field called radio astronomy. It’s been well integrated into modern astronomy and astrophysics.

Weart:

It’s no longer considered some sort of a separate specialty.

Abell:

That’s right.

Weart:

Anybody can do it.

Abell:

And in many fields, of course, to manufacture, design, to build radio telescopes still requires a lot of engineering skill. But the point is that the astronomy done now is of interest in many kinds of astronomy. We know what radar astronomy has done, for example, a sort of off-shoot of radio astronomy. Observations of the sun, the planets — solar system type of astronomy, of interest to planetologists people interested in the sun and plasma physics and the like. Observations of quasars are of course of interest to people in extragalactic astronomy, pulsars to people interested in degenerate stars, neutron stars and so on. The structure of the galaxy; a tremendously important development since radio astronomy. They’re mapping the galaxy in 21 centimeter radiation. Discovery of synchrotron radiation-events in the center of our own galaxy and other galaxies. There’s no one area that you could say is radio astronomy, but all these tremendous breakthroughs into new fields of astrophysics came about through the development of this technique for observing at radio wavelengths, including better antennas, masers and so on. That doesn’t mean to say that there wasn’t a lot of theoretical development at the same time. But theory does not work in a vacuum. One can sit and contemplate his navel, or theorize how many teeth there are on a horse, but you’d better look and see. So I think the great advances in theoretical work have followed, not preceded, the advances in the observational end. Some examples — neutron stars were speculated about by Zwicky who talked about it in the thirties. But until we had observations, radio observations of something happening with very short periods, which could only be something rotating in a second or less, we had no real observational evidence that anything like a neutron star in fact did exist. It was after discovery of pulsars that a lot of people got interested in the physics of neutron stars. Black holes, the idea of Schwarzschild radius, were solved of course Schwarzschild and other many, many years ago. The new thing now in the observations of X-rays, which are suspected to be from material spiraling into a collapsed star, which has a good chance of being something like a black hole. Well, so, we mentioned X-rays. The development of rockets made it possible to make observations above the earth’s atmosphere at X-ray wave lengths, of course from satellites, and gamma ray detectors detected gamma ray bursts, for which we still don’t have good interpretation. Just the development of electronic computers has been a fantastically important development, which again is — what would you call it, instrumental.

Weart:

I suppose, something like that — engineering — something from outside — engineering something from outside —

Abell:

Sure, obviously, the theory of the computer technology goes back to Von Neumann maybe, but the development of high speed computers then made it possible to do things in astronomy that simply could never have been done. And this happened essentially during the war. I recall, when I first came to UCLA, we had an old clunker called the SWAC.

Weart:

S-W-A-C?

Abell:

I think it was K. Maybe it was C. Yes, it must be C. It’s no longer, of course, used. At that time, in 1956, it was still a useful computer. Now, we have little HP-45s and 65s and things that almost do as much. But look at what has happened, the whole space program, all the Mars probes, Venus probes, Mercury probes, the Apollo project — they would be absolutely unthinkable without electronic computers. Speaking of Mariner 6 and 7, in the late sixties, ‘69, I think, when the approach to Mars by Mariner 6 showed something interesting around the south polar cap. So immediately Mariner 7 was reprogrammed, and it took essentially a day, as I understand it, to rewrite the program for the trajectory for Mariner 7. An enormously complicated looking mechanical problem — never could have been dreamed of being done. All the work on stellar evolution, stellar models I did as a graduate student a model for the sun, by a graphical, semi-graphical calculation technique, which took the better part of six months. That was 1953, I guess. I published it.

Weart:

Sort of hand calculator kind of —?

Abell:

Yes, hand calculator aided by some graphs, using Lane-Emden’s equation, by Bondi’s… But the point is, a lot of people did models of stars in those days, and it often would be a year’s job, just to do one rather poor approximate model for the sun or some other star. Nowadays those calculations take a few seconds. People follow the evolution of stars in a far more sophisticated way. The opacities which were very complex and needed to understand the transport of energy in stars could never have been handled properly without electronic computers. Of course, another story, instrumentation in a rather horrifying way — after the war, several astronomers were hired by AEC at Los Alamos because astronomers had some expertise on the nature of hot plasmas under extreme conditions, fireballs, because the physics in many ways was like that of stars-stellar structures. So people like Bownlee and Cox and some others went to Los Alamos to work on the physics of fireball phenomena. While there, they also had the opportunity to work on stellar structure. The same computer programs were used for both and it’s the Los Alamos calculations of opacities of materials in stars that are now standard for years.

Weart:

That’s Brownlee?

Abell:

Bownlee, I think. Cox is primarily responsible for the opacity at work, Cox and his team, Arthur Cox. But it’s kind of an interesting thing, that this was an offshoot of the nuclear bombs (nervous laughter). It was a perverted sort of a contribution, in way, that was unexpected. From the Apollo project of course, there are many spinoffs from the space program, things like ball point pens that write upside down, and heart pacemakers and so on. But things like pocket calculators certainly were an offshoot of the miniaturized computers that came out of the space program. So, these are all discussions of how important the computer is — to program telescopes. Every observatory of any importance now has many computers. At Lick Observatory the Cassegrain scanner is controlled by a PDP computer. We have one down in our department here, for reducing data and controlling, we have a [???] we developed for use with that. Radio telescopes run by computers — the whole space program — every field, every field of astrophysics, even things like reducing your photoelectric observations, reducing plate measurements, people wanting to do proper motion work. It would be a painstaking measurement job, of photographic plates and traveling microscopes, all done by hand, and reduced by hand, years ago. Now, there are automatic machines that scan plates, detect the star images, measure their brightness and location on the plate. And so on. So, computers have touched every field.

Weart:

Do you think these things have speeded up the work? Or have they made some difference in what is actually done?

Abell:

Oh, both. Certainly they’ve facilitated the routine work, but more important, they made it possible to do this that could never have been done. Star structure and evolution are the great example. Much of nuclear physics, controls, even developing other instrumentation has required computer technology and made use of it. So that’s been a key thing. The space program, allowing us to get observations from outside the atmosphere — new techniques which made it possible to get new data, new information. Observations at radio wavelengths, we’ve mentioned; x-rays, ultra-violet gamma rays, all the things like the x-ray sources that may be black holes, pulsars, quasars, Seyfert galaxies, the infra-red radiations in Seyfert galaxies which has been detected with new infra -red detecting devices. They’ve all come about due to the development of new techniques. And they’ve had a tremendous impact on astronomy or astrophysics, because of what we learned, and that creates new interest. People from outside rush in. Physicists got very interested in relativistic astrophysics as soon as it became clear that we now may have a chance of detecting things of interest in relativistic astrophysics, like black holes. Or new checks for general relativity, brought about by space probes, for example. People interested in plasma physics, in physics, are now interested in understanding plasmas in, for example, planetary atmospheres, and the solar wind, to say nothing of inter-stellar space, things like neutron stars and so on. All these things, all these new fields that have opened up, have opened up tremendous new theoretical work, but all of it began because of new techniques. I think that’s the revolutionary thing that’s happened. What if we hadn’t any new techniques since, say, the beginning of World War II? We would probably be making progress, doing things the old way with telescopes. I guess we wouldn’t even have photo-electric photometry, would we? We’d still be measuring star brightness’s on photographic plates.

Weart:

Photo-cells developed.

Abell:

But then of course they developed into photo multipliers — let’s see, when did this happen?

Weart:

Some photo-cells before the war, but didn’t really get started until after the war.

Abell:

But things like 1P21 — when was this —

Weart:

That was war-time development.

Abell:

I think it was. So that kind of detector also, photo-electric photometry made it possible to make much more accurate measurements of star brightness; as a consequence of these new improved measuring devices, measuring techniques, the image tubes, another great important development, we now have discovered the scale of the universe is at least ten times what it was thought to be in Hubble’s time. It’s very interesting to speculate, what might we be doing? I suppose we would still be measuring star masses and radii, as we still today, but now we’re using new techniques.

Weart:

You’d certainly be going at a much slower pace.

Abell:

Slower pace. But more important, we would certainly be ignorant of quasars, of the radio radiation from the galaxy, synchrotron radiation of pulsars of x-ray objects. But this has always been true in history. The development of new telescopes made possible new windows in astronomy.

Weart:

Well, of course, the 200 inch was another post war development also.

Abell:

Yes.

Weart:

In the thirties there were by no means the same kinds of great instrumental breakthrough.

Abell:

That’s right. The 200 inch made important contributions. But even the development of the big reflecting telescope, by Herschel, made it possible to map, to discover objects in the sky — the nebulae, star structures, galaxies which weren’t known to be galaxies then. But these were made possible — this great initial cataloguing of funny looking objects in the sky, which opened up, as we know, a new universe — came about because of the development of the large reflecting telescope. Surveys like that wouldn’t have been possible before.

Weart:

Science in general does follow instrumentation. It has to keep right along with instrumentation. But I think one would be hard put to find a time when there were so many advances in instruments, coming so fast, as they have in astronomy. Maybe this is one of the main reasons for the speed of the advances.

Abell:

Oh, I think it has to be. Of course, larger numbers of people exist too. But it’s the technology that develops that, not only does it affect standards of living and gadgets and things, and pollution and over-population and all those things, but it also develops new science.

Weart:

Do you think the pace of astronomy is any faster or slower now than it was let’s say 20 years ago, when you were starting out.

Abell:

It’s incredibly faster. One should just look at the astrophysical journal on the book shelf. I meant to do this calculation and I haven’t really done it yet. I did it with my own books; when I just rearranged the book shelves a few weeks ago, I noticed that the length of the astrophysical journal on the book shelf is roughly exponential. But I would like to try out the experiment from the first issue, and just sort of estimate the increase in the number of words. Of course, more words don’t necessarily mean more progress, but it does indicate more activity.

Weart:

George Gamow did the same thing for PHYS REV, which is like most science journals, showed exponential growth, and he extrapolated from this that in 100 years, the wave front as it advances across the shelf would be the speed of light. But he said that that does not make a contradiction with physical theory, because all physical theory says is that no information can be propagated faster than the speed of light.

Abell:

Very good. We have figured out, in our building that an important problem is going to be the collapse of the building because of the weight of the journals. That’s the immediate feature. Going along with this fantastic growth in science has been of course fantastic new problems; for example, information retrieval. There was a time, for example when the IAU first formed, everybody almost knew everybody else. Or even AAS meetings. But now, there are so many more people in the field that almost everybody is rather highly specialized. Much of the nice part of astronomy, that it was almost a club, has gone.

Weart:

You noticed this change even during your own career?

Abell:

Oh, sure. Even you, Spencer, must begin to feel that no longer are you a young person at AAS meetings. No, you probably still feel young. But, I guess I realized some years ago that I was way over the median age, at these meetings. That was a sudden change.

Weart:

But that’s your own change. What about the change in what happens at the meetings?

Abell:

When I first went to AAS meetings, single sessions, papers. Now we usually have five simultaneous sessions at meetings. So we have the phenomenon of people rushing back and forth from one session to another, trying to catch the various papers. And of course, as always, with many people there are now hundreds of astronomers doing research in this country, I don’t know how many, 400 maybe, active research astronomers? Maybe more, maybe 600.

Weart:

That’s something I have to find out.

Abell:

Interesting. But certainly, most of what’s been written has to be wrong. That’s inevitable, I think. But still and all, whatever the percentage is that turns out to be right; it’s certainly increasing, along with all the other information.

Weart:

You said there’s an increase in specialization?

Abell:

Yes, unfortunately, because people can’t keep up with other people’s fields any more.

Weart:

How would you break down a specialty?

Abell:

That’s a hard one, That’s a hard one. You could talk about individuals, and what are those individuals’ specialties. I would hate to try to categorize astronomy. People change specialties, too, but — just take any department, what’s so and so working on? People like, in our department, Holland Ford, Dave Jenner, and Harland Epps, are looking at planetary nebulae in other galaxies, getting the abundances of elements of hydrogen and helium especially, in the planetaries — they’re also interested in quasars, and the associations of quasars and clusters and in trying to settle for once and all, is there anything too (ARP’s???) ideas about non-cosmological red shifts. So far, there seems not to be any reason to take that seriously. So they’re interested in extra-galactic studies primarily, from the observational side, and I sure know nothing about the new convection theory that’s being studied by Roger Ullrich, who’s a theoretician.

Weart:

Roger’s still here, isn’t he?

Abell:

Sure. Yes. Maybe you ought to talk to him and get his views. He’s really a great guy.

Weart:

He’s too unknown?

Abell:

I think he’ll be a very influential person in the future. Now Roger is also very interested in the problem of the neutrino. See, there’s a new technological development. Davis built this neutrino detector which should detect solar neutrinos, which should follow from the nuclear reactions in the sun, and so he’s detected no significant solar neutrinos. Why? So Roger has been doing all kinds of theoretical work, asking what restraints can be put on models of the sun, or what restraints are put on by the lack of neutrinos, and as a consequence, he finds there are real problems. It may well be that the sun is not shining by nuclear reactions at this particular moment. Maybe the sun’s luminosity has varied in geological history. He’s done a study of the possible limits of variations in the solar constant. What the geological evidence reveals. But anyway there is a whole new exciting idea — has the sun changed in luminosity in some erratic ways, as opposed to just the general evolution that is generally supposed? If so, these ideas, which may be right, have come about because of neutrino detectors. We didn’t mention nuclear physics, by the way, did we? I guess it’s less clear what instrumental techniques were involved, if any, in developing the idea that the stars shine by nuclear energy.

Weart:

There are always ideas coming in from outside, from the field of physics.

Abell:

Yes, I guess so. Indirectly, of course, it comes from relativity theory — and more than those developments in nuclear physics, sure, and those were instrumental things or experimental things at least. So again, I suppose that even nucleogenesis theory goes back to cross sections measured in the laboratory, the work of Hoyle, Burbidge and Fowler, the two Burbidges and Fowler which was sort of pioneering in nucleogenesis in stars, required knowledge of cross sections gained in the laboratory. This required technique.

Weart:

One of the things I want to do is get the names of people that we might look into more closely. These are people that, if they’re dead, we’ll try to find out where their papers are, make sure that they’re properly preserved. If they’re still alive, we would interview them. Of course, we don’t have time to interview more than a fraction, but at least we could try to make a start, at the very least warn them to make sure that their papers are preserved. What people do you think are important in these developments?

Abell:

Well, I’m sure you know Hubble's papers are in the Huntington Library.

Weart:

I’m thinking of postwar people.

Abell:

Yes, who are the younger —

Weart:

— a list of the people — that we should —

Abell:

Key people that must be on your list would include of course Sandage, by all means. Probably — I don’t want to evaluate people too much on tape —

Weart:

No, no, but — this is all confidential —

Abell:

Sure. I mean, I think Arp is probably wrong on his ideas about non-cosmological red shifts and the like. But I think his work nevertheless has stimulated a lot of interest and studies which have had important fall-outs. He may turn out to be an important person. Certainly Hoyle. Of course he’s not exactly postwar, but I think pretty much so. Most of his important astronomy’s been postwar. It’s very hard, not being organized, to go down the list of who are the main people now living. I ought to get the AAS list — in fact let me remind myself — then perhaps the IAU list — Shklovskii of Russia certainly ought to be on your list, if nothing else, just the idea of synchrotron radiation. Generally, people who’ve made important contributions end up as officers in the societies. Let me just look at who some of the past officers have been, as a check list, by no means a complete one. Gosh, any kind of such discussion is bound to be affected by my personal judgment.

Weart:

Of course, but I’m asking a number of people — list people who’ve won medals and been officers —

Abell:

You’re going to, of course, work through these lists yourself? Gold Medal recipients of the ASP I think make a good list. Recent past, I remember Babcock, Biermann, Hoyle, Luyten — his work has been fundamental work, not new, exciting, and splashy. He’s an old man now. But I think very important fundamental work.

Weart:

What was his work on?

Abell:

On luminosity function of stars, and numbers of faint stars, numbers of white dwarfs. I think he’s given us our best information about the kinds of stars that exist in our part of the galaxy. A person I have extremely high regard for is Dan Popper. He’s not a splashy person. His reputation is not commensurate I think with his contribution.

Weart:

Dan Popper.

Abell:

Popper. He is perhaps, in my judgment, the most careful of the people who are trying to get fundamental data — masses, luminosities, radii, effective temperatures of stars. This is fairly unglamorous work, but without these basic data, one can’t begin on theories of stellar evolution, for example. So I hate to see the fundamental work, such as Luyten’s, and Popper’s, go unnoted.

Weart:

Yes, I’m glad you’re pointing these out, because frankly these are the kind of people —

Abell:

— that one might not think of. They won’t make the newspapers, they won’t be heard of by their successors, but their work will be nevertheless basic to what follows. Lawrence Aller, of course, especially in the early work he did on gaseous nebulae and the abundance of chemical elements, made many contributions. The idea of mass exchange in binary stars, and contributions to stellar evolution — one of the first people who had the idea of mass exchange was Miroslav Plavec, who’s been in Czechoslovakia. A person who carried the work much further, because of better equipment, was Rudolf Kippenhan, a student I guess who will succeed Biermann, as director of the Max Planck Institute of Munich. Currently I think he’s still director of the Gottingen Observatory. Rudolf Kippenhan, he’s the principal German expert, I think, in stellar evolution. We mentioned Biermann, of course working in plasma, comets. Again, I’m being very disorganized, just thinking out loud. In this country, Martin Schwarzschild is fundamental. You have him on your list of course Spitzer. Sandage and Schwarzschild made early contributions to stellar evolution. The work of Hoyle and Sschwarzschild and then much later, many people of lesser names, but I think also contributions — Henyey, he developed new computing techniques. He’s dead, unfortunately. He died prematurely, maybe last — he was Roger Ulrich’s principal advisor.

Weart:

Wonder what happened to his papers?

Abell:

I don’t know. Well, he didn’t publish very much, unfortunately, but was a very bright guy. I think Jesse Greenstein could tell you, and Jesse Greenstein is another name you must have on your list. I know that Rudolf Minkowski was mentioned at this meeting in Pasadena, Rudolf — I think his famous work will be his early studies of the optical objects that were radio sources. Walter Baade, who did fundamental work, I guess on the idea that there different populations of stars, which now is interpreted in terms of different chemical abundances and ages, and he did the first work that led to the new distance scales. Or to realizing that the old distance scales were wrong. But of course, he’s done many other things in the past. You’re asking, of course, more about postwar people. Icko Iben on stellar evolution made important contributions. The fellow that’s now studying early stellar evolution, I’ve forgotten his name, a young fellow. I think he’s quite good. Larson. Of course, it’s hard to evaluate work that’s still in progress. Sometimes it will turn out not to be very important. Larson is at Yale. Richard B. Larson. Kraft did early work showing that novae apparently are all in close binary systems. Bob Kraft at Santa Cruz. And Don Osterbrock did fundamental work in interstellar material, and also in stellar evolution theory early on. I’ve mentioned the work of Cox on stellar opacities. I think Roger Ulrich is going to be a big name in astronomy in the future. Still pretty immature I guess. Davis in his neutrino experiments would be a person to take note of and Joe Weber in attempting to detect gravitational waves — I think Joe Weber is going to turn out to be wrong in his experimental technique, but if the relativity theory is right, there exist gravitational waves, and I’ll be surprised if they’ve found some someday. And in a way, I think he will go down in history as spearheading or at least starting the attempt to determine, or to observe gravitational waves, even if he doesn’t find them. Kip Thorne is certainly a shining star in the relativistic astrophysics field, and Steven Hawking, extraordinarily brilliant person in relativistic astrophysics — Hawking. The poor fellow has what I guess is MS. I’m sure he hasn’t long to live. He’s a complete, almost a vegetable, and he’s still making enormous contributions.

Weart:

Is that so?

Abell:

He has been at Cal Tech as a visitor, and I think he’s not there now. Or he may still be there. One might check. But he can’t speak very well. Steven Hawking is normally at Cambridge; Institute of Theoretical Astronomy, Cambridge. I should think of other fields, I’ll come back to this field. Let’s see — Harold Johnson did some fundamental work in photometry, and of course Whitford also in relevant fields of photometry, and Stebbins. Stebbins and Whitford really were the first modern photoelectric… (workers). [???] in x-ray astronomy, I guess was one of the first to make x-ray observations, wasn’t he? Dimitri Mihalas in physics of stellar atmospheres. I think he’s the number one man in that field now. Again, he has great insight, and has made very important contributions. John Bahcall, very important contributions, very prolific fellow, and he’s made — maybe his most important earlier work was the prediction of solar neutrino emission, and getting neutrino astronomy sort of started. Many of the people, I’m not able to really evaluate too much. They’re too far out of my field. Let’s see other names — of course Chandrasekhar, you want on your list. Stellar dynamics. Stellar atmospheres. Theoretician, but laid a lot of important groundwork in the theory. Jan Oort, I don’t need to tell you about Oort. People like Fermi and Spitzer you know. Otto Struve is dead also, an old timer, interested in mass exchange and peculiar things in binary stars. Kuiper, in his work on planets — again, should be on your list — these are mostly dead people. W.W. Morgan in spectral classification, and also spectral classes of galaxies. Willy Fowler, don’t forget Willy Fowler, main light in nucleogenesis, in doing the nuclear physics work, important to it. Grote Reber, his contribution was making a radio telescope; — they started the thing — Reber. He’s at Ohio State, or was. I guess he still is. Bowen, physics of interstellar medium, spectroscopy, of course, but recognizing the Nobelium lines were forbidden lines, in gaseous nebulae. Stromgren in his fundamental work on HII regions and HI regions and the distinction between them. Neugebauer in history of astronomy. I don’t know if you want to go into that. John Bolton, important pioneer in the construction of modern radio telescopes. Ed Salpeter in nuclear physics. Clemence in celestial mechanics is important. Just looking at various people who’ve been officers — a lot of these names have already been mentioned, like Shapley and Struve.

Weart:

— You’re looking at the AAS Society.

Abell:

Yes, I’m looking at former officers — and present. And present. Fred Whipple, especially for his study of comets. Broader in the study of minor planets, as well as mechanics problems. Let’s see — Mort Roberts is a good man in a lot of radio astronomy. Margaret Burbidge, both Burbidges, you’ll be talking to them I’m sure. Now, let’s see, some of the former might councilors might give me some ideas of young good people — they’re not all young any more. Humason, don’t forget Humason, probably you wouldn’t. I mentioned Aller, I mentioned Popper. Let me think of the field of galaxies. Who are the people I think are making —? Well, I’ll tell you one guy is very, very good is Jim Peebles at Princeton. Cosmology, distribution of matter in the universe, a bright guy and marve1ous insights. Who’s the fellow that succeeded Hoyle at Cambridge? I know him well; it’ll come to me. He succeeded Hoyle as the head of the Cambridge Institute, and a very, very good man. I’m sure the name will come to you. I mentioned Babcock, let’s see — you might talk to ABT. He’s done a lot of work in spectroscopy, fundamental, collecting the material on stars, and also he knows a lot, and can give you a lot of insight about who the major contributors are. Herb Friedman you should put down, for work on early space. I forgot to mention Maarten Schmidt, and Matthews, Tom Matthews for their early recognizing that quasars must be extragalactic, with large red shifts. Carl Sagan I think will be an important name, for his work on the surfaces of planets, and biological processes in planets. I mentioned Osterbrock. I’m probably passing by people I shouldn’t. Sidney van den Bergh has done important work I think in extragalactic astronomy. George Field in interstellar material. Models of dust in the galaxy. Owen Gingerich, of course he will give you a lot of help on history; I think you’ve heard of him.

Weart:

Well, yes.

Abell:

Let me look through the people who are currently presidents of commissions of the IAU or on organizing committees. This will give me some —

Weart:

What are you looking at now?

Abell:

Now I’m looking through the Astronomer’s Handbook of the IAU. Actually, this is the appendix, called the Astronomer’s Handbook of the PROCEEDINGS of the Brighton meeting which was the last of this kind of book that came out. Let me just see if any names come to mind. Celestial Mechanics is so far out of my field, I’m a little reluctant to name names, but perhaps William Kaula, he’s at UCLA — Kaula has done some work I think on the figure of the earth from satellite observations. If you want to get some of the earth’s — the work on plate tectonics — oh, Peter Goldreich, brilliant young theoretician, and in modern type celestial mechanics, with a wide variety of problems he’s worked in. Let’s see — position astronomy is fundamental and important, and I don’t know the people that are best that you should talk to. A recent president of the commission was W. Fricke, but gosh, I don’t know who the main people are. Luyten probably is in this group. Of course positional astronomy is very unglamorous. It’s now done at places like the Naval Observatory. But gosh, it is important!

Weart:

You have to know where it is.

Abell:

You have to have fundamentally good position astronomy, and things like time keeping. A.B. Meinel I think has played an important role in development of modern astronomical instruments. Of course, again Babcock we’ve mentioned; Bowen, they made important contributions in instrumentation. Solar activity — Oh, Grant Athay is an important person in solar physics. Who are the others? — well, there are many top people. I’m probably not the best person to say who they are especially out of this country. I’ll remind myself of some names in a minute. Lou Goldberg obviously you should talk to. You can’t get all these people.

Weart:

I can’t talk to everybody you named.

Abell:

But many you can. Bob Leighton at Cal Tech has done important stuff I think, especially in the space program. Morton at Princeton, whom you know, I’m sure and W.O. Roberts, Colorado. Probably Schluter at Munich. I mentioned Shkovsky. Smeerd in Australia. Development of very sophisticated equipment for the purposes of making solar observations. I guess they have the finest solar observatory, radio solar observatory. Also Wild. Solar radiation, let’s see – I see more names here. Gosh, who are the top people in this thing? Newkirk maybe?

Abell:

I’ll make the list shorter by looking at only people on organizing committees. Thinking of comets, the key person in that is Whipple, probably the main light. Satellites — I hate to pass up whole fields of astronomy because they’re unglamorous — oh, the moon, Kuiper of course we mentioned, what about Dolfus? All Dolfus’ work hasn’t been accurate, but certainly he made — oh, and Don Menzel of Harvard should be on your list. In the old days, a lot of fundamental work in astrophysics. So many commissions, things that were — say, who are the big people? We mentioned Oort and Schmidt in galactic structure. Oh, C. C. Lin and Frank Shu. I think I have the right name, Shu? Chu? Shu maybe, I’m not sure. I think he works for Lin if I’m not mistaken, Frank Shu — that wasn’t the name I was thinking of, I’m sorry. He also is a good man. He works in problems of massive change in binary stars. But who’s the fellow that worked with Lin? You’ll get his name when you look up Lin. He’s at MIT. Phil Morrison of MIT is a good man to talk to, you know him, I’m sure.

Weart:

Has he done much in —?

Abell:

Oh, he’s a physicist, but he’s dabbled in, I shouldn’t say dabbled — dabbled in astrophysics, and had novel ideas that I think have excited a certain amount of work. Attempting to interpret things like quasars and pulsars, and M-82, with more conventional ideas, before going to new esoteric physics, esoteric new physics. I think it’s a healthy thing to do. Variable stars; who are the big people in — Well, Christie, in the study of variability of Cepheids and understanding the physics of it. And John P. Cox. I think it’s John Paul, J. P Cox. Now, let’s see — in galaxies, — Ambartsumian and Bondi, and of course Tommy Gold in cosmology. Bondi and Gold were fathers of the steady state theory. Gamow was important in cosmology, but he’s gone. Dicke, obviously. Ivan King has done some pretty good work. Ivan King, at Berkeley, non-glamorous but I think good. Mills, again, observations of radio objects. I think Jerzery Neyman ought to be considered; his work with Elizabeth Scott. He’s a statistician and Elizabeth Scott works with him at Berkeley. He’s now retired. They haven’t done a whole lot, but they’ve done some interesting things in giving us insight about the distribution of galaxies. They did the most thorough study of the question can the present distribution of galaxies be interpreted in terms of the model of complete clustering?

Weart:

Who else is at Berkeley? Who do you think would be the best people there to talk with? I don’t have time to talk with more than one or two.

Abell:

King is pretty good. I think he’ll give you a lot of insight. Who has made important contributions in different areas. Shakeshaft is coming up, I’d say — well, I don’t know, maybe Shakeshaft should be mentioned. I’m not sure of how important his contributions are, but he’s certainly an active young fellow. Zwicky has done a lot. I can’t remember the name of — this fellow who succeeded Hoyle. Terrific man. Very famous person. Oh, we can go on and on. I don’t know how useful it is when you have too long a list.

Weart:

Well, if I spent two hours interviewing all of them, and then, two hours going to and from, it would easily take me a few years.

Abell:

Of course, there’s going to be a lot of overlap. Many of the people we’ve mentioned aren’t so important to talk to, but at least it helps if names are mentioned by various people. If there are some names everybody mentions, you know you must not overlook them. I would hope that you would not overlook, in general, the people who are doing important fundamental work. I mentioned people like Luyten and Popper.

Weart:

Yes. In some ways, I’m particularly interested by the people that may only get mentioned by one person, because they’re sort of out of the way.

Abell:

Yeah. Right. They don’t come to your mind, when you think who the most important astronomers today.

Weart:

— but they’re equally important.

Abell:

Martin Rees is the name of the guy I was trying to think of, Rees, I’m sure you know him.

Weart:

Right.

Abell:

Let’s see — what general fields have we completely overlooked, that might be really important? Who are the important people, for example, in the study of the structure of planets? Obviously in the old days, Rupert Wildt and later his student, Wendel Demarcus, but I’m sure there’s very important work being done today in that field that I’m not up on.

Weart:

Yes. Of course unfortunately, some things like planetary physics I’m just going to have to have out. Can’t cover everything.

Abell:

Yet, in the history of modern astronomy, one surely can’t leave out what’s been learned about the solar system. It’s so fantastically phenomenal. You know, before the war, I think most astronomers had a somewhat patronizing attitude toward the solar system, because the planets were things that amateurs looked at. But hasn’t that really changed now? We now have close-up observations of Mars and Venus, not so much Venus, just the outer atmosphere, but Mercury, temperature measurements, knowledge of the atmosphere. We‘re landing the Viking on Mars, hopefully in ‘76. Gosh — radiation field of Jupiter and so on. We now think we understand how the inner planets formed from accretion of the solar nebula. Very important stuff, too. Should leave it in.

Weart:

Well, some people are doing some work on this, these programs —

Abell:

Maybe it just should be at least acknowledged, in any history of modern astronomy, even if it’s too big a field to cover thoroughly, one should acknowledge the important breakthroughs.

Weart:

It’s true. See, I’m in kind of a bind, because I’m the only person in the world who has this history of physics, and I’m trying to devote the next three years probably to astrophysics, and meanwhile, nobody’s doing particle physics, nobody’s doing geophysics — laser optics —

Abell:

— geophysics has revolutionized — An unhappy thing that’s happened, because of astronomers’ somewhat patronizing attitude toward the solar system, not everybody’s but too many, I think in the recent past, now, with the space program, so many opportunities exist that we find almost a new breed of people. And we find separate departments of planetary science, and planetary physics, which I think is kind of too bad, because many of the problems are fundamental astronomy, and of interest — even in common with other astronomical type problems.

Weart:

A sort of an artificial split.

Abell:

I think so. And I think that the new techniques drew people in, and since there weren’t many astronomers interested in planets, people went into these fields.

Weart:

We’ve been talking about other fields, but we might also talk about other kinds of things. For example, have there been some people whom perhaps we haven’t mentioned, but who were teachers, for example, had a lot of good students.

Abell:

Yeah. There sure have been. To put my finger on them all that is not going to be easy. Certainly Schwarzschild and I think Spitzer. Menzel got Lawrence Aller into astronomy. I don‘t know how influential he’s been as a teacher in other ways. I’m trying to think of who the great teachers are. I’d have to say Schwarzschild. Feynman, of course. Greenstein has had a number of students, and has played a major role in education through the Cal Tech development. Who are some of the other outstanding teachers I can think of in astronomy? Otto Struve. I think Owen Gingerich has been. A number of people have been very interested in educational problems, and have done a lot of work on teaching aids and so on, such as Wentzel. I don’t know how much of a teacher he is personally; perhaps more as a public educator than as a trainer of astronomers. Who are the people who have — oh Chandrasekhar. Who are the people who have turned out good astronomers? Osterbrock, I have to give Osterbrock a special plug, because I was his first graduate student. Kippenhahn, he’s a superb teacher. That’s Rudolph Kippenhahn. He’s the one I mentioned earlier, in mass exchange, stellar astronomy. A terrifically good teacher, who had a number of students in Czechoslovakia, is Plavec whom we also mentioned earlier. Oh, Lawrence Aller has had many students. Again, all this is going to be unfair, in forgetting very important people that should be on such a list. For example, who is there at Wisconsin now that I think is outstanding in the number of students he’s had — I don’t know — Arizona, maybe Ray Weymann, should be mentioned. I don’t know how many students he’s had. He’s had some. He developed a top notch department there. And by the way, Weymann we should have mentioned as an astronomer, Weymann an important still fairly young astronomer who’s at Colorado? I’m not sure. I didn’t mention deVoucauleurs before. I have mixed feelings about how good an astronomer he is.

Weart:

Who?

Abell:

De Vaucouleurs. But he’s done a lot of work, and I think it’s been important, even though a lot of people have disagreed with details of it. I think he’s stimulated other people. He revived the idea of the local super-galaxy, for example, the local super-cluster, as we now call it. Let me think, who are — oh, W.W. Morgan probably has a lot of influence on students. I say probably, I think so. Maybe only girl students. Just kidding.

Weart:

What about, other than teaching, what about people who have started institutions — fund raising organizations —

Abell:

Well, what’s his name, in Maryland — Gart Westerhout. Shane promoted the 120 inch at Lick. We don’t need to talk about Hale in that category. Oh, the fellow that made the big telescope in Britain — Bernard Lovell. He really fought to build that installation, too. Dave Herschem maybe? I don’t know how much influence Dave G(?) has had, but I think he has played a role in — at least in developing the National Radio Astronomy Observatory. I’ll tell you a fellow who really conceived, I think, the idea of the National Observatory, got it started — that’s John Irwin. He didn’t actually build it up, but I think that he had an important early role in it. Irwin is currently at Newark State College. He hasn’t accomplished as much, but he had some early ideas, early on, that I think have been important. Jesse Greenstein certainly built the department at Cal Tech up. A lot of good people there. I don’t know who the good people were that built up Lick. Who, for example, got the Cerro Tololo, Las Companas observatory, I don’t know who the people are that were responsible for selling this idea. I’m not so sure. Whitford certainly has played a role; we mentioned Greenstein before, in developing national interest in modern astronomy. He’s head of an important committee which you know about.

Weart:

I should talk to him.

Abell:

Oh yes, you ought to talk to Whitford.

Weart:

Let‘s see, where is he now?

Abell:

He is at Santa Cruz. I guess he must have retired, or be very close to it. Maybe he just retired. My mind goes blank sometimes, and it shouldn’t. George Field — he’s at Harvard. I don’t know to what extent he’s built something up. That would be hard to justify. So let’s see, we’ve talked about people who have built observatories — who have important contributions, who are good people in the field of Ed. I’m sure we’ve left out a lot of the top notch ones, and mentioned a lot that aren’t too top notch, but at least it’s a start. — It’s easy to mention many important advances in modern astrophysics. It’s hard to rate which — to make a complete list, and make sure that we know which are the most important. But I think we’ve touched on a lot of them.

Weart:

Well, we’ve sure covered a lot of ground. I wonder if we could talk, too, about some of the social changes. We mentioned some earlier, like specialization growth of journals. I think there are other things that have changed — let’s say, ways in which your life is different from the way the life of your professors was when you were a student.

Abell:

My personal life has (laughter) one bad thing that has happened at big universities, at least at the University of California, is that there’s an undue growth of administration bureaucracy. Too much of our time is spent telephoning, filling out reports, requisitions, that sort of thing. That’s probably a local and a trivial point, although I suppose that’s probably universal. Parkinson’s Law or something. It affects astronomy also. The growth, on number of astronomers has been both an important thing for developing astronomy and advancing it, but also it’s been a — it’s had its price, in that you’ve lost a great deal of the association with your colleagues that we once had, and you associate with your colleagues in your immediate field more than you do in all fields. Still, I think the international meetings like the IAU are marvelous, because even though we are much more specialized there still is the opportunity to go to review papers, review sessions, and see old colleagues, especially for us older guys — not old but compared to the young.

Weart:

Have the IAU meetings changed much?

Abell:

In size, they’ve got an awful lot bigger. The general format has been the same, I think, many more people going. The difficulties and expenses of course have been harder. We had a big change, social change, which maybe more — I hate to talk about cycles. I don’t believe in cycles, except the well-established ones. But since I got my degree, when I was a graduate student, there has been an interesting kind of change. About the time I started school, I think professors who were astronomers taught more courses, had less time for research — the typical teaching load was, we’ll say, two courses — they did not have an easy access to government funds. Research was a hard job. It was hard to get funds, hard to get to the observatories and make observation and so on. After the war, things got quite easy for a while, in that there was a considerable amount of money for astronomical research. A lot of new departments were being built. A lot of new jobs opened up for graduate students. And this accompanied an enormous growth in the number of people, and moreover people getting their degrees in the late fifties and early sixties, and even late sixties — I think especially during the sixties, when the growth occurred, first of all with respect to the space program and the need for astronomers. I think that all the young people really went through having such an easy time that the older people would say they were highly spoiled. They’d gotten used to the world with a fence around it, and to having almost unlimited resources, in the way of research resources, secretarial resources and so on. And weren’t so used to doing the kind of dog-work that the older people were used to doing for themselves. Now we’ve seen a tightening. Federal funds have tightened up. The space program is largely cut back. Moreover, the sudden increase in the number of departments of astronomy led to an overproduction of PhDs. There no longer are many openings in PhD granting institutions or departments. So people are having a harder time finding jobs. I think it’s going back in some respects more as it used to be. People are more willing to take jobs, for example, in less glamorous institutions. That kind of a social change, I’m not sure that’s what you were driving at —

Weart:

— well, yes. Anything, really.

Abell:

Certainly the sixties were a golden age for astronomy, and for young people getting into a new field, making exciting contributions. It’s certainly going to be harder. I think you’ll find, people who are successful now are going to be, by and large, better people, because you’ve got to be. The competition is a lot stiffer and the funds for supporting astronomical research have not kept up with the increase in the number of people or inflation. I’m not sure there’s been an actual lessening of funds for research, but relative to the buying power of the dollar, there has been. So, that kind of social change has occurred. How about public attitudes? I guess, when I was a graduate student, people thought of astronomy as a very esoteric field. Almost nobody had ever seen or heard an astronomer. During the height of the space program, there was a lot of misunderstanding about astronomy. But at least, people got much more familiar with the subject. Not well educated in it, but much more interested in it. We find even today enormous interest among laymen and among students in astronomy. I think our classes for liberal arts students are bigger than they’ve ever been before. I think one very interesting phenomenon has been widespread growth and interest in pseudo-science and the occult. There have always been cranks in astronomy. Astronomy — because most people don’t know much about it, and because it’s interesting to most people, has attracted a great many people who are — well, cranks, also charlatans — you can name a bunch, like Velikovsky — but the amazing thing about Velikovsky, who is a crank, I think an honest crank, is the phenomenon, the widespread following he has. The ease with which people will accept novel ideas that are widely refuted by the entire scientific establishment, and the words even, “scientific establishment” take on a bad connotation to many people. It represents something stodgy and unimaginative and uncreative. Whereas this kind of an acceptance of anything that challenges the establishment, of course, also means a great gullibility on the part of many students and the public.

Weart:

Do you find any of this in the astronomical community itself?

Abell:

— I’m talking about mostly the public attitudes.

Weart:

Graduate students?

Abell:

Less. No, the graduate students are pretty hard headed. I don’t know — you’d never find a student in physical sciences, I think, not a sane student, who for example believes in astrology. But on the university campus, I guess a third of the students believe in astrology, and probably 10 percent of the faculty, if you include all departments. Among the general public, most of them don‘t know the difference between astrology and astronomy. Or many people don’t. UFOs or UFO-logy — the Von Daniken phenomenon — who I think is a charlatan — as is I think Berlitz, with his Bermuda Triangle — I guess, I think there has been more interest in occult and pseudo-science and charlatans and cranks and radical ideas, I don’t mean radical in the sense that they’re new and right, but ideas that challenge the scientific establishment —

Weart:

Do you think any of this has affected astronomers?

Abell:

Oh, I think inevitably it must affect, in the long run, because it affects public credibility. Or it shows their credulousness. Judgment — I think it must. But it’s not obvious yet how. I really think that it’s important that scientists attempt to explain what their field is to the public and what they’re doing. After all, especially in astronomy, the public pays the bill, in the long run, and I think they have a right to know what we’re doing. We should devote better efforts to our public education, and also try to counteract the fake lore, as Bruce Murray called it — somebody — I think it was Bruce Murray that wrote an article recently about mythology and what he called “fake lore.” It’s an interesting phenomenon. Oh, a couple of card carrying astronomers, Plodgerman and Goobin(?) have gotten into the act. I cannot believe that they are serious, in their Jupiter effect, for example, and I would be glad to say on this tape that if that thing ever gets really famous, it is not as famous as I think it was thought to be — as I think they thought it would be — if it gets famous, I think it will go down as a hoax, on their part. I suppose, they see Von Daniken getting rich, they figure, why can’t we get into the act?

Weart:

What about, to begin with, in the astronomical community, has there been any change in what can be published, or how things get published? Whether you publish things or not?

Abell:

I think the speed of communications is keeping up pretty well. The journals are getting too fat, but the turnover time is, if anything, going down, especially through things like the Letters of the ASTROPHYSICAL JOURNAL. The ASP is a good journal, gets things out fast. But even in the Ap J itself, this is six months to a year. It’s always been that. I think that’s reasonably fast. I think the problem is simply that there’s so much published, one can no longer keep up very well with it, even sometimes in his own field. As far as problems with referees, or getting papers accepted — no, I think anything that is legitimate, usually is eventually accepted. There are obviously injustices. Sometimes referees misunderstand papers, and I’m sure there must be cases where referees have maliciously rejected papers because they didn’t agree with them.

Weart:

You’d say, things are about the same.

Abell:

Well, I don’t think that’s increased. In fact, I think because there are more journals, I think it’s probably easier now to get things published. The present editor of the ASTROPHYSICAL JOURNAL is extremely fair, I think, tries very hard not to suppress what even could be good science. By the way, I think ABT deserves credit for doing a marvelous job in editing that journal.

Weart:

Is there any difference in the way people are recruited to the field, or get trained when they come in the field?

Abell:

Oh, sure. Today there isn’t much recruitment in the field, except for the very best people, because the job market is — there are still jobs for astronomers, but they’re different kinds of jobs. Astronomers can find teaching jobs in colleges and universities, but not — only the best can find jobs on faculties of PhD — granting institutions in astronomy. So recruitment has changed in the last year or two or three. But training, of course, has got to change to keep up with the times. Since World War II, the training of astronomers has been much more physically oriented than it was say before the war, when astronomy was more phenomenologica1. It was physical then, but less so than now. Now, as things have progressed, you have to have all the better training in physics.

Weart:

There’s been a lot of talk about influx of physicists and is this true? Do you feel it has an important effect upon how things are done?

Abell:

Yes, I think it’s true. I’m not sure it hasn’t always been true. I’m not sure what the difference is between physics and astronomy which — obviously a guy who’s working in the laboratory on bubble chamber photographs or in acoustics, or in quantum mechanics, is at that point primarily a physicist. But nothing prevents a man interested in high energy physics from getting interested in cosmic rays, and cosmic rays are astronomical in origin. So I guess — and people like (Herb) Friedman, who was a physicist was getting into space observations — many of the, much of space science has attracted people because of their expertise in radiation theory or fundamental particles or cosmic rays. I think, though, astronomy is where things an happening, in the last decade or two, especially with the new phenomenal discoveries of quasars and pulsars and stellar evolution, beginning to understand the formation of the solar system and cosmic rays. So naturally, if there’s new physics it’s likely to be in the hot areas, and I think for this reason, a lot of physicists have gotten interested in astronomical problems.

Weart:

Do you think this has made any great difference in the field itself? Has there been any real change?

Abell:

Well, the change has come about, again, because of the new developments, new techniques, observations. Then the physicists can bring their expertise into the field to help interpret the new observations. So, sure there’s been a change. But if you mean, do I think it’s a bad thing, that physicists are horning in — no, I think it’s a great thing.

Weart:

Because you mentioned that the style of teaching seems to have changed. Perhaps that might be an effect.

Abell:

Yes, that preceded of course the recent surge. As you need more specialized theoretical techniques to understand problems, or more sophisticated engineering techniques to understand how to operate equipment and so on, the training must get more specialized and more rigorous.

Weart:

I see, then it develops the field.

Abell:

I think it develops the whole development of the field, sure. Now if one wants to make a contribution in stellar structure and evolution, you’ve got to be damn good at physics, plasma physics, and hydrodynamics now. You didn’t have to know hydrodynamics to be a structure man, but nowadays, to understand mass exchange in binary stars and convection theory, rotation and so on, you’ve got to know hydrodynamics. So it’s a lot more physics that one must learn, fundamental physics, to be able to make contributions at the frontier of knowledge — it’s just pushed further back, so you’ve got more ground to work over to reach that area. And you can’t learn everything, so you have to specialize more and more. I think some institutions are maybe too specialized. We try here to give all the students a kind of overview of major areas of astronomy initially, and then encourage them to specialize in certain fields. I think it’s important to do that for perspective — and also because will go into teaching.

Weart:

One more thing. We’ve talked about a lot of concepts, social development and so on, but we haven’t mentioned specific institutions. I just wonder, is there any particular institutions, observatories, universities that have changed in important ways? That has come up, or declined or changed their orientation?

Abell:

Well, of course, after World War II, the biggest powerhouse in the world in astronomy developed at Cal Tech. Also, after World War II, the University of California developed astronomy far more than it had before. There was a department at Berkeley and a few astronomers at Lick. But now almost every campus has people interested in astronomy, and there are PhD granting institutions on three campuses. So California in general, if you include Cal Tech and the UC system, has become an enormous astronomical center. The Hale Observatory is primarily postwar. The National Observatory at Kitt Peak, the National Radio Astronomy Observatory, all radio observatories, of course. The Chile observatories, now. The new Siding Springs observatory in Australia — Siding Springs, with the 4 meter telescope. The 48-inch telescope in the Southern Hemisphere, completing our sky survey. New solar observatories — Sunspot, of course, in addition to Kitt Peak. University of Arizona developed new equipment. Of course the University of Texas has a 100-inch telescope. The Soviets have their new — five meter, whatever happened to that? No, it isn’t five meter, six meter — no one knows where it is, what’s happened to it. I guess it’s not operating. But the telescope at the Crimea Observatory. So all radio installations — there are many new optical observatories — also, don’t forget, again, the space program, which is fantastically important. JPL is in a sense an astronomical observatory. And that’s developed largely postwar. As far as institutions — I think Cal Tech and Princeton are still the best. I think there are a dozen good top departments of astronomy in the country.

Weart:

Have there been any that I’ve declined?

Abell:

Yes, I think so. I think these may be temporary of course, changes in staffing patterns.

Weart:

Let’s say, over the past 20 years.

Abell:

I think Michigan has declined. I think Harvard had declined, I think it may be picking up again, through recent good people. Just two or three different staff members can make a big difference in the whole department, because there are so few people on astronomy staffs. Michigan could climb back. At the moment, I think they’ve declined from their position. I think they were a leading department, and are not now. Cal Tech of course has grown. Arizona has certainly grown. UCLA is brand new. Santa Cruz is brand new. Washington is new, Hawaii is new, Maryland, Virginia they’re not all on an equal footing, I don’t think, but they are new departments which have good people. Ohio State has expanded. Texas has improved a lot. It is easier to point to ones that have grown, not the ones that have declined. But any department will go up and down, you see.

Weart:

Things look very good for the next period.

Abell:

I think as far as the number of good astronomers and facilities, things are very fine. Support may be a problem. The Ha le Observatories is having financial problems, as you know. That’s going to be a continuing problem. And I hope that we can stabilize support. I guess, speaking of the social things, one thing we touched on but didn’t maybe —- the last moment or two can re-emphasize — the space program in the sixties had an enormous impact on astronomy of all kinds, not just through the space program itself, but through the need for more astronomers, to work in the space program. These people trained in that field. This drew people. This encouraged the development of new departments and training of new astronomers. So all fields of astronomy grew, got support — a sort of fallout from the space program. It had an enormous impact on government spending. As well as the new techniques that the space program itself brought about. Computers, which we mentioned so much before and new detectors. And then, when you turn off the faucet in Washington, and cut back on a program like that, it has an enormous economic effect on this great number of astronomical trained people which we produced. Suddenly, you’ve left them dangling. We must somehow stabilize government spending to avoid this. It happens not only in space but of course military spending, all fields. There’s got to be a more stable, long term planning, rather than spurts. You have a spurt of activity, you train, you create great teams — then you turn it off and the teams are lost, and you have to start from scratch next time. I think it’s kind of a shame. We had a crash program to go to the moon. Now it’s gone, and we’ll have to start from scratch before we ever do it again. We can no longer go to the moon. We don’t have the rockets, and none are being built. We have unmanned space exploration, and maybe that’s all we should have right now. But I hope it’s financed on a long term, stable basis, rather than at whims of Congress.

Weart:

Well, I think this would be a good place to stop.