Interview with Jack Eddy, April 21, 1999
In Michigan by phone, conducted by Spencer Weart

WEART: This is Spencer Weart, and it's April 21st, 1999. We're recording you. You want to just state your name for the tape recorder?

EDDY: Yes. It's Jack Eddy, now in Michigan, talking.

WEART: Jack, who were your parents and what did they do?

EDDY: I was born in a small town in southeastern Nebraska of 1600 people. My dad managed a cooperative farm store. It was a grocery store and a farm produce store. Farmers would come in and sell their cream and eggs, and other produce from the farm, and then take their cash and go next door, in the other half of the store, and there were groceries for sale. That was the store my dad operated for quite a while, and I worked there as a young boy until I got into high school.

WEART: Farmers with horses and so on.

EDDY: At the time--I can't believe it now, because it was in the 1930s--there were still horse-drawn wagons on the street. They would park near the courthouse in town. And there was a guy who was employed to walk around town with his little cart and clean up after the horses.

WEART: You had electricity, but probably some of them didn't?

EDDY: Yes, it was a changing time, I think. But interesting that when I was young, rural electricity was not that common and horses were still used as draft animals on the farms.

WEART: Okay, back to your parents then.

EDDY: My mother was a wonderful person. Neither my dad nor my mother is alive now, but she had gone to college a year, and was a country schoolteacher before she and dad were married. I have a brother who is two years older than I, and a sister who is two years younger than I, Bob and Lucille. We were a family of three children in a modest but happy home. I was the first and only one to get a college degree in my family. I wasn't sure we could afford university schooling, but the little town that I lived in, Pawnee City, was also the home of one of the two U.S. senators from Nebraska, Kenneth Wherry: an ardent Republican, who appointed me to the Naval Academy in Annapolis in 1949. That offered me a chance to go to school. And that's where I got my undergraduate schooling.

WEART: So, so how did you get started in science then?

EDDY: There was not a real strong program in science at the Naval Academy in the years that I was there: 1949-1953. At least at that time, there was a lot of engineering and particularly marine engineering, but not much science. But we did have a course in celestial navigation, which I understand is no longer taught anymore.

WEART: In the GPS days, yeah, no more sextants.

EDDY: That course gave me a love of the sky. I actually got in some trouble at the Naval Academy, because I crawled out on the roof one night to look at the stars. At the time I lived on the fourth (top) floor of Bancroft Hall. I remember I was looking for Draco, of all things, this weird constellation that didn't have much shape anyway. And so I was out there looking for it after Taps, which was a very bad sin, and in came the officer of the day and noticed that one of the midshipmen in the room was not in his bed. He found me on the roof. He gave me, I don't know, four or five hours of extra duty, which means getting up before the usual 6:15 am reveille and running around the athletic track for an hour or so, carrying a rifle and wearing leggings. So with a punishment like that, it made me want to go into astronomy all the more, I guess. But I was graduated, went to sea, served four years as a naval officer in the Korean War, and elsewhere around the world. And then I decided to leave the NAVY and was accepted in the graduate school of the University of Colorado in mathematics.

WEART: In mathematics.

EDDY: I'm not sure why they let me do that.

WEART: You applied for astronomy, and they let you in, in mathematics?

EDDY: No, I wasn't even thinking astronomy. I knew I liked astronomy, but I kind of thought maybe mathematics is what I might be good at. Colorado was far from the ocean and near Nebraska and that's why I went out there. When I got to Boulder, like you*, I was looking around the university and found this little observatory and a small program in astro-geophysics that had just been started. I wanted it to be more astro and less geo but in any case, I decided that was where I really belonged. So before I started in mathematics that fall, I was accepted as one of their first graduate students in astro-geophysics.

That was in the fall of 1957. I remember going over to Walt [Walter Orr] Roberts's house to hear the radio broadcast from Sputnik, which had just been launched. As you know, the High Altitude Observatory there was associated with the University. It was then on the campus. Its primary interest was the Sun and solar physics with the addition of some upper atmosphere stuff. So that's how I came to become a solar physicist, or perhaps more honestly, a solar astronomer. (Because I never was that good at physics, I think I never could have gotten through the courses that you did at the University of Colorado.)

WEART: I barely made it. So the usual route you pick up the science that your thesis advisor is - What was your thesis advisor's specialty?

EDDY: My thesis advisor was Gordon Newkirk. And my thesis was in balloon astronomy. He was at that time, in the late 1950s, trying to find new ways to observe the corona-with the help of the coronagraph. You know the High Altitude Observatory was associated with an observatory up in the mountains at Climax, Colorado, at an elevation of about 11,000 feet. And its principal instrument was a large coronagraph, with a 16-inch primary lens. He was trying to observe the corona better by going to even higher altitudes, and see if you might be able to see the corona outside of eclipse.

WEART: Right, with balloons and aircraft and stuff like that.

EDDY: Yes, the early work that eventually led to satellite astronomy and orbital coronagraphs. But at the time I was in graduate school, Gordon was getting ready to try a coronograph on a high-altitude balloon. The first one was a manned balloon launch, where he sent a guy up in a gondola from Rapid City, South Dakota, to see if maybe with this hand-held coronagraph that obscured the disk of the Sun, at a balloon altitude of 40,000 feet or so, he might be able to see the corona. He couldn't for the sky was still too bright.

Then he thought an unmanned balloon would be the way to do it with automated pointing. It could get higher, to about 80,000 feet. Gordon was in communication with Martin Schwarzschild at Princeton, who at the time was taking his photographs of the disk of the sun -- Martin's brief foray into solar physics to record these fabulous, I think still almost unequaled, pictures of granulation that he made from an automated balloon telescope in the late 1950s. And I got sent off to take part with Schwarzschild, which was one of the high points of my scientific career, in one of his balloon launches from Minnesota. I stayed with him a few days to kind of learn the instrument a bit.

My thesis was based on a later balloon experiment that Gordon supervised, also from Minneapolis area, to send up an automated coronagraph, and to look at the corona. As a sort of sidelight, we also took calibrated measurements of the brightness of the sky near the sun, at high altitudes, which was what was limiting the more direct observation of the corona. My Ph.D. thesis, in a department that was chiefly interested in the Sun had little to do with the Sun. It had to do with the brightness of the sky. From that I could then work backwards using calculations of Rayleigh and Mie scattering to figure out what the particle distributions were with height, what size particles were there, and the feasibility of using coronographs above the level at which humans could work. I loved the night sky a lot more, and more distant and romantic things, more than the Sun. But you do what you have to do to get a degree.

WEART: Let's skip rapidly through the next few years, up to the early 70s. Sort of give me a quick summary of your career. You have a number of papers on various spectral lines and infrared spectroscopy. What was your interest during that period?

EDDY: I think my principal interest then was teaching, because I was teaching courses in solar physics that were all consuming for me. And I think maybe, Spencer, that's the thing that I do best. I really did enjoy that, I must say. A lot of the solar astronomers of today came through my class. They weren't great because they took my class, but I knew them. As far as research, I think I was an opportunist and somewhat of a dilettante.

WEART: The research was something to do to keep your professional credentials.

EDDY: Yes, I think that's what I was doing, and I did a bunch of quite different things intentionally. All my professional life I have striven to be as broad as possible. My critics could rightly also say, "Yes, and as shallow as possible."

WEART: Well, I can't fault you on that one, personally.

EDDY: I knew you of all people, wouldn't. But my reasons for taking this less-traveled road were many. One is the inevitable thrill of discovery when you wander into new areas. More importantly, you also avoid the danger of being too comfortable in too narrow a niche. I truly believe the sayings that there is no hope for the satisfied man and that without fear there is no learning. Entering a new field with a degree in another is not unlike Lewis and Clark walking into the camp of the Mandans. You are not one of them. They distrust you. Your degree means nothing and your name is not recognized. You have to learn it all from scratch, earn their respect, and learn a lot on your own. But I also think that many of the most significant discoveries in science will be found not in but between the rigid boundaries of the disciplines: the terra incognita where much remains to be learned. It's not a place that's hidebound by practice and ritual. I have always tried to keep moving between fields of study and it shows up, I think, in my vitae.

WEART: Yes, and this is a good point to ask you now about how you got into the Medicine Wheels. [Native American rock configurations]. How did that get started? What got you started on that?

EDDY: I took interest in the Bighorn Medicine Wheel in about 1970 by reading something in the Denver Post Sunday Magazine, where they had devoted about one column-inch to this relic of the early Plains Indians. And it looked kind of fascinating for it had an apparent East-West symmetry that hinted at a sunrise-sunset alignment.

WEART: Somebody reported on these rocks up in Wyoming, was it?

EDDY: Yes, on a mountain top, and it looked very astronomical, and going up there sounded like a real adventure. I got into it that way. I think the lesson I learned there, again, was never to be dissuaded when you first step into another discipline. Because as soon as I asked the archaeologists about it, and the anthropologists, they would tell me right away that there's absolutely no point in looking at it. That it had been there too long, and too many people had looked at it already and learned all there was to know. And this notion of astronomy and sky-oriented alignment wasn't going to work out anyway. I have since learned that when you venture into something new - even in your own field - you're always going to he told that it's not possible, or unnecessary, or someone else has already been there. And you never should be dissuaded. So that was a really good learning experience for me.

It also gave me more press than I think I deserved. I was on all kinds of [radio and TV] programs. I got to do a piece for the National Geographic.

WEART: But now you found these astronomical alignments. How was this accepted at the High Altitude Observatory, in the solar community? What did that do for you there?

EDDY: Nothing positive, I can guarantee you that. Taking a detour that's interdisciplinary and colorful like that might make you feel good--the person who's doing it--but it doesn't help your annual reviews and stuff. When you get involved in another field, your own will count it as pure dalliance, or even betrayal and think you have disappeared from science altogether. I think it was kind of frowned upon, and quite definitely showed up in my performance reports.

The next divergent direction I went was into history. And that came out mostly from teaching the course in solar physics at the University of Colorado. I found out, Spencer, as you must have too, that one way to put students at ease, is to keep reminding them that it wasn't too long ago that nobody knew more than you guys sitting out there in the classroom about the chromosphere or whatever it is that you are telling them. By using historical examples, and explaining what came before, and how this or that got discovered, I think it helps put students at ease and more easily taught. And by digging into history, I got involved in past eclipses of the Sun, and wrote a number of historical papers, and through that I later came across these curious things that led me down the trail of the Maunder Minimum.

WEART: Okay, before we get specifically to the Maunder Minimum, I'm curious where else you may have encountered ideas about solar variability, about the carbon-14 relationship and so on. For example, one thing I've noticed is that in 1965, there was a conference in Boulder where [Hans] Seuss spoke about these things. Do you recall that conference in particular, for example?

EDDY: I didn't go to that one. As you know in 1965, part of the year I was off with you on an island in the middle of the Pacific [on a solar eclipse expedition]. At the time I was looking at coronal emission lines in the near infrared.

WEART: That was at that point. Oh.

EDDY: The eclipse on Bellingshausen Island was on May 30, 1965, when you and I were there. But I can't claim that I had been walking down that trail of carbon-14 at that time, or know much about it. I didn't get into that until I started doing historical work on the Maunder Minimum about eight years later.

WEART: I see, so how did you get started on the Maunder Minimum? In your 1976 science paper, you mentioned Gene [Eugene] Parker.

EDDY: Right, Gene Parker was an occasional visitor at the High Altitude Observatory in Boulder. He's from the University of Chicago, as anyone who listens to this knows. I remember him coming there in the late 1950s and giving a colloquium on his wild idea that there was a solar wind, before that was accepted by anyone. I remember the unanimous reaction of the solar physicists to his idea: what a ridiculous notion that was -- a wind blowing charged particles out of the Sun. It reinforces what I said earlier: that new ideas, if they are worth anything, will always be met by a knee-jerk rejection on the part of the disciplinary experts. It also tells something about Gene, who was never afraid of stepping into new things. Later, in the early 1970s, he called Maunder's early papers to my attention: did I know about this thing in the past? (I did not.) Because he knew I had an interest in history. I don't know just why he told me. He may have known that at that time I was cautiously and with some prejudice digging back into the history of sun weather relations, which is another story.

WEART: That's of the sunspot cycle story?

EDDY: The 11-year sunspot cycle and correlations with it, which I was very negative about.

WEART: You thought, as most people did, that it was an impossible thing.

EDDY: I had been taught that while the Sun indeed affects the upper and outer atmosphere of the Earth, purported connections with the troposphere and weather and climate were uniformly wacky and to be distrusted. I still believe that to some extent, for there is a hypnotism about cycles that seems to attract people. It draws all kinds of creatures out of the woodwork. The claims that were made for associations between weather events and the Sun I thought were pretty preposterous. One of those that turned up was this notion that Gene told me about. About the work of Walter Maunder 100 years before, when he had thought that there was a prolonged period of time in the 1600s when the Sun wasn't so active.

That really piqued my curiosity, and I began digging into it. The trail was, initially, purely historical, initiated by Gene Parker telling me about Maunder, and driven by my prejudice of trying to find examples from the past that would disprove, once and for all, the notion of strong sun-weather relations. A devout negativism on this subject was the gospel at the High Altitude Observatory anyway and the catechism that I had been taught and had taught to others. And although I was indeed an acolyte, I was trying to examine the early origins of Sun-weather claims, like unrolling and deciphering the Dead Sea scrolls of solar physics. But it was mostly a love of history that took me down the trail.

WEART: I see. So just along with your other stuff, from time to time you would go and try and dig something up.

EDDY: I did it all on the side, quite on my own, and sneaked it in here and there. For something had jolted my professional life, which was probably the worst and maybe also the best thing that had ever happened to me. That was in 1973. I had been at the High Altitude Observatory for almost ten years at that time. Mostly teaching courses, and doing these eclectic forays into this and that. Nothing very profitably. There came along a major cutback in the funding for our parent organization, the National Center for Atmospheric Research, NCAR. They had to lay off a number of people. I was one of those selected to be let go.

WEART: Your Medicine Wheel work didn't do you any good, in that case. [See Eddy, J.A., "Astronomical Alignment of the Big Horn Medicine Wheel", Science 184, 1035, 1974]

EDDY: The Medicine Wheel work hurt me, as did the notoriety and media attention that had come with it. That was the answer to your question a little while ago. But also, and to be honest, my publication record was not that long, and highly irregular. So, Gordon Newkirk, my thesis advisor, who had then become the director of the observatory, had the task of telling me that they were going to can me. But to make it easy on me, he said, "But don't worry. Just go right across the street over there to the (University of Colorado's) Department of Astro-Geophysics. Julius London has told me that they are very eager to hire you." And I thought, "Well, maybe this isn't so bad after all. And I'll be able to teach, which I really like." So I went over to see Julius London, head of the Department and, I thought, a friend, and told him what had happened. He said he knew about it, and I told him what Gordon had told me. Then he let me have it. "Well", he said, "I don't know what Gordon said, but what we're going to do is wait and see if anybody good gets laid off." That moment was the low point of my life. For many months, I scrounged around to find a job without success. I found out how hard it was for a person with a PhD to get another job at that time, and often wished I didn't have one, for I was often told, true or not, that I was overqualified for the few jobs that turned up, here or there.

WEART: Yes, that was a time with a lot of cutbacks.

EDDY: There was an opening for an editor at Sky and Telescope, and I tried for that. The Questar Corporation (that makes telescopes) was looking for somebody to help run that place. I tried for a job at a small optical lab in Los Angeles. I was kind of desperate for I had a family of four children-two in high school-to support. Then some of my friends at NASA thought that I'd had shown some promise as a writer. They offered me a temporary job, because I had worked as a P.I. on a Satellite Coronagraph in the 1960s, writing a book for NASA as part of the series on the Skylab spacecraft. So I got a job to write this book, in Colorado, that kept income coming in. It also enabled me to continue work on the Maunder Minimum although not openly. It was a job that I had to stretch out as long as I could, until I could get a [permanent] job. It became for me, intentionally or unintentionally a kind of Scheherezade exercise, to be prolonged as long as possible. Which I did. But it enabled me to do a bunch of traveling, mostly to Harvard, where two of the solar instruments on the Skylab were built, and where there were excellent historical libraries. And to Washington where I could use the Naval Observatory Library.

WEART: One of the world's great libraries for this stuff -

EDDY: In connection with my visits with investigators on these satellite instruments, I would go and spend time in the libraries that were far better than those in Boulder. In this way, I was able to read and collect original texts-mostly in Latin-from the time of the Maunder Minimum. And collect old pictures and original data on both sunspots and aurorae, and naked-eye observations from the Orient.

WEART: At this point, you were beginning to believe that the Maunder Minimum was real.

EDDY: I was beginning to change my mind and to believe it was real based on the original documents I read, and as a result of immersing myself in the time, as happens when you dig into history. But it was a shock to me to suspect that my original feelings and biases were wrong.

WEART: And at this point, the evidence was still mainly sunspots. You hadn't gotten into the aurora or the carbon-14 yet?

EDDY: It was entirely sunspots at first. I wanted to check these original records, so I did that as much as I could, and the NASA editorial job enabled me to do that. Then, when that came together, I began to look around for other ways that there might be for checking on it -- that Maunder and Sporer didn't have. I knew I would face an uphill battle convincing my colleagues about the reality of the Maunder Minimum if it leaned entirely on accounts from so long ago. Why should you trust someone in the 1600s when we are so much smarter and know so much more now? As scientists, we're trained to discount what one finds in old books, I think. You know science does, of necessity, have to look at things through a rather narrow window of time, because most of what earlier generations believed has been replaced by something else. Some things may be of interest for historical reasons, like whether Galileo was left-handed, or Niels Bohr thought this or that, but usually not for practical or applied ones. And I thought there ought to be some way to check on what Maunder, and earlier, Sporer, had claimed.

Because I had been trained in astro-geophysics and knew something of the other ways that the Sun affects the Earth, I looked hard at historical records of aurorae. Because of my interest in history, I looked very hard at oriental naked eye sunspot [observations] in the hundreds of years before the Maunder Minimum and after, because they were continued after the advent of the telescope. I pushed it as hard as I could. And once when I was telling Gordon Newkirk about my early findings, he said, "You know, you really ought to look at carbon-14." That answers the question you raised earlier.

WEART: Yes. So he had heard about it, but you hadn't really been aware of it at that point.

EDDY: No. Not before Gordon's suggestion, which was extremely valuable. I taught myself about cosmogenic nuclides and all of that. And tree rings, and bristle-cone pines. And I got acquainted with the Laboratory of Tree Ring Research in Tucson.

WEART: So tell me, the absence of the corona at the eclipse hadn't hit you yet. I mean, you had been working on coronagraphs, but you hadn't gotten into that.

EDDY: I tried to determine whether the appearance of the solar corona during the years of the Maunder Minimum could help verify or disprove a major change in solar activity. It was not easy, or very certain, for the corona was not well known, nor looked for, at eclipses in the 17th century. The question, I think, is still unsettled. At the time I was doing the work in the '70s, I became pretty convinced that the corona was not visible at eclipses or very much reduced in size and brightness, based on accounts from eclipses at the time.

WEART: That was when you first started reading the accounts from that period. It struck you that it wasn't there.

EDDY: Yes, although we couldn't expect them to use the word "corona" or talk about it as part of the Sun, for that didn't get established for another century and more.

WEART: But you were looking for something that looked like what you would see in an eclipse.

EDDY: Right, exactly. Because of my own eclipse experience. I had gone to a bunch of them by then, and what I thought was, well, if the sunspot numbers were really low, the corona should have looked a lot different. And then I tried to picture in my mind what the corona would look like if you really turned the sunspot number down almost to zero and kept it there for 10 or 30 or 40 years. What would the corona look like? It should be very dim with few coronal streamers, if any. The real-time accounts seemed to confirm that. But it was a little dangerous to make much of it because the corona hadn't been studied or even looked for at eclipses at that time, and I think people see what they're trained to look for and can miss what they don't expect to find. Almost no one saw more than one total solar eclipse in his or her lifetime for they were not the festivals that they are today, and astronomers hadn't yet learned about world travel and boon-doggles. So I'm still not sure.

WEART: Well Jack, a reminiscence from when I was at Boulder: I remember some teacher, I think it was probably you, talking about the Egyptian sun god, and this image of the solar disk with wings, and saying, "Gee, maybe this was a corona observed back in ancient Egyptian times." Remember that?

EDDY: Yes, I do remember that.

WEART: So that was way back before any of this. You were clearly, at least thinking in those terms.

EDDY: You're right. Thanks for remembering for me. I also looked through and visited a bunch of museums, including those in Boston and Washington, to look at how the Egyptians had portrayed winged suns, and whether the winged sun wasn't an awful lot like how the corona appears at the minimum of the sunspot cycle. And it was, because it was all concentrated in the equatorial regions. But making the assumption that therefore there was a corona that was noted way back then is really hazardous, I must say.

WEART: Right, you know you can't go very far with that.

EDDY: That's true. The historical part was a great joy for me. I was once told every boy wants to be an archaeologist; but everybody who loves books would like to be a historian, I think. I just really got interested in the early history of our understanding of the Sun. At that time, I'd also done a bunch of work on the eclipse of 1878, which was my real love at the time: one that went through Colorado. It was also a time of [solar] minimum. All those historical things kind of came together for me at that time. And although I was working on the Maunder Minimum while temporarily employed as a book writer by NASA, the High Altitude Observatory was nice enough to let me keep an office there. My salary came from NASA directly and I was not a regular member of the High Altitude Observatory or NCAR staff. When the work got published [Eddy, J.A., "The Maunder Minimum", Science 192, 1189, 1976] and became accepted, I was in this interesting position of having been canned by an observatory that wanted me back on board.

WEART: And this comes before you published -- talking about it around the observatory? I want to hear the story now of how you started telling people about it, and how you decided to publish in Science and so on.

EDDY: I wanted to publish it in Science because I thought the story was of broader interest than to solar physics alone. It was also a journal I've always respected even more than Nature, and they had been nice to me in publishing the Bighorn Medicine Wheel article and put it on the cover. I must confess also to egoism. At the time, and particularly having just been fired, when I needed self assurance, I was keen about seeing how many journals I could get a picture on the cover of. It was not unlike the way big game hunters collect trophy heads to hang on the wall. I had collected a couple by then, and I thought, "They're going to go for this." So I sent it there, and they did, and it landed on the cover. Part of the story also is where the name came from.

WEART: How did you come to that-it was a very good name.

EDDY: Maunder was a kind of a second-tier astronomer at Greenwich so far as I could ascertain. The best known of his writings was a popular book on astronomy and the Bible. He was definitely a religious guy, as probably most scientists were in the late nineteenth century, and was not in the league of Norman Lockyer or the other leading solar astronomers of the day. So when he started uncovering this stuff -- much as I later uncovered what he had done -- he didn't get that much press for it. I had to dig around for his papers. He had also done it in two surges, separated by about 30 years: one back in the 1890s, and then again shortly before his death in the 1920s. But he kept it in his mind all that time. He was not the first to call attention to the phenomenon: the latest before Maunder, was Gustav Sporer, in the 1880s, I think, but the trail goes back before that.

WEART: Right. So how did you come on giving it this felicitous title of "The Maunder Minimum?"

EDDY: I knew I had a lot of selling to do if people were to accept the notion of such irregularity in the Sun, and I sought a name that people would remember, "Maunder Minimum", with all those m's had a kind of onomatopoeia.

WEART: You just like the ring of it. By this time you clearly had some experience in writing. You'd been writing for National Geographic and so on.

EDDY: I like words.

WEART: Again, it goes back to your teaching experience, I guess.

EDDY: And, you know, the temptation was to think that it might someday be called the "Eddy Minimum": that is, to call it nothing in the hope that someone else would do that. But being from Nebraska, I could never do anything like that. I also knew I wasn't the first to find it, and it wasn't really mine. I think I did quite a bit for Maunder with that name. Particularly because he also got the idea from somebody else. He got it from Sporer who was a German astronomer. So, among the shots I took after publishing the paper were some from Germany that said, "You know, you really named it after the wrong person." Which I knew very well.

WEART: Right, but alas, Sporer's name didn't start with the right letter.

EDDY: Right, and the other sounded so good. I also, deliberately chose the title of the paper in Science, calling it simply the "The Maunder Minimum." I knew nobody would know what that was. It might have been better to include words about sunspots or the Sun or whatever, but I really wanted to plant this name in people's minds and remember what it was. At the time I'd also come to realize this one other point that I would like to include here about the philosophy of science.

After being once disappointed on not getting any recognition for something that Gordon published, having to do with the Moon and the corona, that I felt I had helped him do, I came to realize that in science the proper credit for something goes not necessarily to the first person who thinks of it, or writes about it but to the one who can convince his colleagues and the doubting world that it's true. That for almost anything you do, someone will probably stand up and say, "You know, 20 years ago, I looked at that and found this same thing," and so forth. But the truth is, it's the person who can make it stick in the textbooks [who deserves the fuller credit].

WEART: Yes, and in this case, I think it was putting it together with the aurorae and the carbon-14 and so on, so that it could be seen and it wasn't just an anomaly.

EDDY: Yes and that's just why it seemed to me okay too, to not be too fussy about crediting Sporer and the others before him in the title of the thing.

WEART: Okay, now tell me about this Science 1976 article. Did you have any problems publishing it? How was it received?

EDDY: It was extremely well received. All the things happened that I had hoped for. Probably more than anything, I wanted to get people reading it who weren't in solar physics. I got swamped with letters and invitations and TV and press exposure when the paper came out. Those years were definitely the high tide in my professional life.

WEART: Because I notice you also published in Natural History magazine, and Scientific American. That was on your initiative? You decided you really wanted to spread it around?

EDDY: Yes, I really wanted to write a more popular version of it. And I did that one for Scientific American. I wanted to tell it more like a detective story there, and at that time I'd done a little more on the connection with climate. But I was swamped with letters, a lot of ones that really touched me, including from non-solar astronomers whom I'd always considered just the gods of the profession. And they'd written, "You know, that was really a nice paper."

WEART: By the way, do you have this correspondence?

EDDY: I wish I'd kept more of it. I think I kept some, Spencer, I know what you're asking, I should have kept it.

WEART: Yeah, I'd love to have copies of some of that, or at least make sure you have copies of some of the letters from that period.

EDDY: Nope. I sure wish I did. And I don't know, it was better received than it deserved. Moreover, the people at the observatory began to become interested in it, which surprised me, although the local response was far slower in coming.

WEART: Were you invited around to give a lot of talks and stuff?

EDDY: I was invited to give too many talks. I was giving for a while, an average of 50 talks a year over every place around the world, although it was also a good experience for me and opened a lot of doors. Although, I found that after a few years I was giving the same talk over and over. I'd always try to tailor and add a little bit to fit the audience and the occasion. But it was a story that people liked to hear. And at that time, I found out I wasn't too bad at giving talks. So I began being asked to be an after dinner speaker and cruise lecturer and stuff like that. It was the "hot wire of success" that I had never known and that can be hard to hold on to without burning yourself up.

WEART: Now tell me, Jack. The Maunder Minimum had been there for a long time. And then, you know, there was this DeVries carbon-14 thing. So in a certain sense, as you say, it was already there. Why was it your paper that made such a huge impact?

EDDY: I think because of what I was saying a while ago, because I really pushed on it real hard, like a door-to-door salesman, for I believed it was a profound finding. The year the paper came out in Science, the High Altitude Observatory allowed me to go to the International Astronomical Union for the first time. And I did this thing--I look back and I don't see how I could have done it at the time. But I made copies of the sunspot-number diagram that I extended back to 1600. No one had ever seen that before with this big flattened thing in there from 1645 to 1715, suppressing the normal 11-year cycle.. I stuck one in the mail box of every astronomer who was attending that conference in Grenoble. And I gave a number of talks.

WEART: And also you mentioned in your Scientific American article that there was a prejudice, which you had shared, that the sun just somehow couldn't be or shouldn't be variable.

EDDY: I was really fighting that, for it is so deeply ingrained, and not just in solar physics.

WEART: Jack, did you experience that? What was your--

EDDY: My first feeling was doubt and disbelief that I had been taught in my three or four years as a solar astronomy student, was that the Sun was indeed variable, but regularly so. The Sun was after all a rather ordinary star. Dependable but rather boring in terms of temporal changes. And so anything that claimed it was something else sounded to me really wacky, as did claims that its variations were enough to influence the weather and climate on Earth.

WEART: The Sun was just well known and an ordinary star.

EDDY: Well known and ordinary. After all, it has always been synonymous with constancy and regularity. As steady as the Sun, rising and setting every day. And always burning bright. You can always count on it.

WEART: Right, been there for billions of years.

EDDY: So when I read Maunder's and Sporer's claims from the 1890's that several hundred years before that the sun had behaved strangely for seventy years, it seemed almost preposterous. And in the long-standing traditions of the High Atltitude Observatory, where I had been trained, it needed to be shot at, even after all these years, and dismissed once and for all. So I set out to demonstrate that what Maunder had claimed was really nonsense. I felt I could do that by applying other tests that Maunder didn't have: like our better understanding of aurorae and so on. And so I tried them. And every one I tried seemed to confirm what Maunder and Sporer had said.

WEART: I see. So you really started by trying to make it go away.

EDDY: I started by trying to make it go away, mostly because of a prejudice about sun-weather relationships, and what I thought was true about the sun. In time I realized that there was a more profound and philosophical message in the Maunder Minimum: that people want the Sun to be more constant and regular than perhaps it is. The connection with carbon-14 I think was the clinching thing. I had become certain enough on the basis of historical records, and aurorae, and the Chinese sunspot records, and the absence of the corona (or what seemed to me the absence of the corona at that time, or a very, very minimum corona). Even though none of these lines of evidence might have been strong enough to make the case-to convict a criminal in court-the combination of them all pointing the same way was to me more than convincing. It was like the strength that can be found in thread or string when enough strands are woven together. That's what finally convinced me and I was ready to publish the paper. And then I looked into the carbon-14 thing, learned more and more about that and found this DeVries anomaly that the carbon-14 people had found long after Maunder was gone. It was coincident in time with the Maunder Minimum and of the right sense-that is, what one would expect to happen to carbon-14 production were the Sun unusually inactive for 70 years.

You're the first person who has mentioned that name [DeVries] to me in many years Spencer. It fit together so well, and I think has since. The ensuing work on Beryllium 10 from polar ice cores has also helped confirm the Maunder Minimum. When I die, I'll think that's one thing that I did that I'll feel absolutely certain about. That the Sun really does go through prolonged period of anomalous behavior, and will again some day.

WEART: Right. Now let me ask you a couple of side issues. You mentioned the Science article and I think somewhere else this business that I think you did with Gilman on a possible change in the solar rotation. Anything to say about that?

EDDY: I think that's also true. That's also a political story, but that is also what you would expect. Peter Gilman at HAO was working on the [solar] dynamo stuff then, and we collaborated to look at solar rotation during the Maunder Minimum. I had just returned from Harvard, where I had been a scientific visitor. I'd been offered a job at Harvard, by the way, after the Maunder Minimum paper appeared.

WEART: That was at Harvard Astronomy Department?

EDDY: In the Center for Astrophysics.

WEART: Harvard Smithsonian Center for Astrophysics, right.

EDDY: George Field, who was then the Director, offered me a tenured position there. I couldn't believe it having just been fired not long before by the High Altitude Observatory. That probably answers your earlier question about how the Maunder-Minimum was received. It was received better than it should have been, and it made me look much bigger and better in science than I really was. When Harvard offered me a job, the High Altitude Observatory started thinking, "Maybe we ought to hire this guy back." So I came back initially to do a little piece of work with Peter. And out of it came the rotation paper. The rotation story, I think, was also a lasting conclusion. I think where it went wrong was later looking at the size of the Sun. I think I was pushing historical records a little too far and too fast on that one.

WEART: Changes in the solar diameter, yeah. But the rotation [rate], again you went back to old, old records.

EDDY: I went back to original records made during the years of the Maunder Minimum. These were drawings of the Sun that I had come across in rare books libraries while looking for the Maunder Minimum. I saw how carefully made these were. It had also helped convince me that the historical reports made at the time of a lack of sunspots were to be trusted. If you look at those drawings that were made by Scheiner and Hevelius, and others in the 1600s, the Sun is portrayed in the kind of detail that modern journals would readily publish today. They were precise, and excellent.

WEART: They projected it and traced on it, or whatever.

EDDY: They'd do a large projection, and trace it out. They were very methodical and careful about it.

WEART: And as far as I know, the rotation, you know, there it just sits. We have these old records and we don't have much else. So there it is, and what else can you do?

EDDY: It was pretty clear that the surface rotation had changed. And I think where the people began to raise doubts was, "Yeah, but you know, the sun isn't a solid object and it kind of swishes around."

WEART: Not clear what you can make of it.

EDDY: Yes, but I think that rotational changes helped corroborate the reality of the Maunder Minimum.

WEART: Okay, now the next part, and it's really almost a separate part, is deciding that there were correlations with climate. I mean, okay, so the Sun is variable. And at that point, I think it was an assumption, I don't think it was a deduction that there might be a change in the solar constant, and therefore change in climate.

EDDY: I don't know if anybody had ever really invoked the solar constant seriously since Abbot's early work. I think I had kind of pushed for that as a possible explanation initially, because I had attended a conference-I don't know, maybe you were there-that Hal [Harold] Zirin held at Big Bear Observatory in the '60s that had re-opened interest in the solar constant.

WEART: Solar physicists were just inevitably concerned about climate.

EDDY: They were, but they were also very skeptical about the sun-weather connections that had been proposed.

WEART: Because so much nonsense had been written about it.

EDDY: Exactly. And they were also disdainful about the solar constant. The solar constant was to most solar physicists a joke. It was like saying, "I'm doing my thesis on the solar plexus, or suntan lotion" something. It had so little to do with what they saw as the really exciting parts of the sun. At the High Altitude Observatory anyway there was this obsession with radiative transfer theory, under non-thermodynamic equilibrium conditions. I can't imagine anything duller, but that somehow had almost everyone obsessed. That was what you worked on. Or else you'd work on longstanding but prosaic features such as flares or faculae or prominences. These other things that had to do with the Earth were considered a bit beneath an astronomer and certainly an astrophysicist, and were best left to the amateurs, or maybe to someone at the fringe. So the possible climate connection with the Maunder Minimum was also kind of a blow to me.

When I began to look into things initially to try to find out what the climate was like during that time, I looked at paintings, among other stuff, from the 17th century, of which there's a good many.

WEART: So at some point, you thought, "Well the solar sunspots were different, maybe the climate was different."

EDDY: Maybe the climate was different.

WEART: But you hadn't heard at that point about the Little Ice Age or that kind of thing?

EDDY: No, no. I had to learn that stuff. I read as many climate books as I could, talked to climatologists, looked hard at other records, tried the glacier advances and retreats. Pieced together what I could.

WEART: You have an article on climatic change, and you give thanks to, let me just mention, Peter Gilman, Val LaMarche, Juan Carlos Lerman, Murray Mitchell, Minze Stuiver. Any of those you particularly remember interactions with?

EDDY: Very strong with all of them. Val LaMarche, who's dead, was such a wonderful tree ring guy, who'd looked closely at that stuff. Murray Mitchell was a climatologist and a scientist's scientist. The others are carbon-14 people. Minze Stuiver is an unappreciated national treasure who has done nothing but superb work in carbon-14 at the University of Washington in Seattle.

WEART: I don't see H.H. Lamb in there. He was one of the--

EDDY: I did contact him and he helped me a lot. I probably should have thanked him. It was all an exercise in pushing off into other disciplines. And as you must know, you have to break in. It's like walking into a hostile Indian camp, you must expect an unfriendly reception at first, at least. You've got to convince them that you're honest, that you're really after this thing. "How about this? What about this?" Initially, they'll tell you that you're probably wrong. Then they might slowly come around. And that's what happened in all those cases.

WEART: They just started feeding you all the stuff that they knew about the glaciers and so forth.

EDDY: The hardest, least certain and most treacherous part of my work on the Maunder Minimum, Spencer, was the climate connection that you're asking me about now. For one thing, by the way, any solar astronomer who wants a grant renewed or something-

WEART: Always talk about weather and climate, right.

EDDY: They will hint as a payoff for their work on the Sun through weather and climate, even though it may have nothing to do with what they propose.

WEART: Yeah, you sort of wink and stick it in for the benefit of any congressman who might look at it.

EDDY: My Maunder Minimum paper in Science was cited a lot. But it was also used by other people submitting proposals, who must have thought: "Oh boy, here's something. I'll drop that baby in the references to show to the people reviewing the proposal how important weather and climate studies are." So I knew that I was dealing here with something very, very dangerous. That I needed to be extremely careful. I tried to be as careful as I could.

In time, I became more and more convinced that there was a likely long-term connection. And moreover, the sense of the connection was that when there were few sunspots, as during the Maunder Minimum, the world should be a little bit cooler. That told me that the most obvious and simple cause was the solar constant. And the sense of the change, based on climate correlations, was a diminished solar constant when there were fewer sunspots. My thought also was that it might well be the radiation seeping through the Sun that's causing the sunspots to go up and down, not vice versa. Not necessarily that the sunspots were cutting off radiation, as we know to be the case today, by the way.

WEART: Right, but that there was some internal change of which the sunspots were one manifestation. Well, we still don't have the full answer to that one.

EDDY: And then when I started getting the carbon-14 data from Minze Stuiver and from Paul Damon and Juan Carlos Lerman at Arizona, I began to see that if you stretched it back in time, it really seemed to fit the climate record. That's when I was writing this stuff about looking like the fit of a key in a lock. It looked like if you stuck in the solar key, it just hit all the tumblers in the climate lock. It was really something. I think, though, that's where I knew I was getting into soft sand. And it was partly that that made me then ease away from this long-term solar behavior, and particularly long-term solar behavior and climate stuff.

WEART: What kind of resistance did you encounter? Were there any particular people or places that explicitly resisted it?

EDDY: Climatologists were really skeptical about it. And I can say that the Europeans were very skeptical about the solar part of it.

WEART: The European climatologists, not astrophysicists necessarily.

EDDY: I think mostly both. I realized I was getting into kind of a territorial thing here. Several people wrote papers saying that the Maunder Minimum couldn't be true, what Eddy's done about the historical stuff isn't right. What he's failed to recognize is that the Thirty Years' War was going on then, as we all know here in Europe so people weren't looking at the Sun at the time.

And I knew about the 30 Years' War and all the rest of it and the Peace of Westphalia. But it was kind of a personal thing. It's like somebody in Japan would come over here and tell us about something about George Washington. So there was a bit of resistance to that. Owen Gingerich used to tell me that if you wanted to write a history of astronomy in Lithuania or something, for God's sakes don't let a Lithuanian do it. He said you've got to ask somebody on the outside. And I was dealing here with kind of European history in a way. The climatologists were far more skeptical, just in general.

WEART: You mean because they'd heard so much from the solar people over the years?

EDDY: They had heard so much from the solar people over the years, exactly right.

WEART: I mean I know, for example, at this time Kondratiev was publishing stuff. I mean everybody was predicting what the next year's climate would be on the basis of various cycles.

EDDY: It's worse than you think. And there were people on there around at different research institutions, around the US too, had made a living at doing solar weather things. And it was all kind of nutty. And it was an awful lot of curve fitting. And I think I probably went too far about being skeptical. But I was uneasy about it. But still, it was there. Then when the measurements of the solar constant finally came along--

WEART: The satellite measurements, yeah.

EDDY: The satellite measurements long after the Maunder Minimum, that made me feel good that the way the solar constant varies does indeed--

WEART: Now, when I ask you a little before that, around 1980, there were people like Haurwitz and so on who were talking about how the sun solar cycle might influence climate by way of the ozone layer. Did you have any interactions, any thoughts on that?

EDDY: No, I guess I wasn't as interested in the mechanics of the connection as I was about what was happening on the sun most. And maybe that was a failure. By that time, I'd begun to look at other things. There had always been thoughts about that. Who's the Nobel winner I'm trying to think of who did work in atmospheric chemistry, even did some of that? Paul Crutzen who was I think a super scientist and had come to know, personally, very well, looked real hard at that and thought maybe he'd found something. There are so many of these little pebbles that have been picked up that people thought was a key to the whole thing, but I never looked at them real closely. The Academy got me to write an Academy study that was, I think, a big step in sun weather relations that I'd pushed pretty much towards the very skeptical side. A bunch of other things I published around that time after the Maunder Minimum were trying to say, "It looks very interesting, and it looks like there may be a correlation with the little Ice Age, and perhaps things before that." But we had to be very careful about thinking that this means that at every sunspot maximum there's going to be something on the Earth, and every eleven year sunspot minimum there's going to be something or other. And be very careful about trying to correlate the rainfall in St. Louis with the local, the daily sunspot number. That this is quite different when you're talking about long-term time scales. And I kept trying to preach that story. And it was in the course of that, I think, that got me into the final chapter of what I've done. And that was into the Whole Earth kind of thing.

WEART: Yeah, let's talk about that. So you've done your Maunder Minimum paper. You'd published papers on the connection with climate. And then where does your career go from there?

EDDY: Probably all that fame of sorts and TV shows and stuff, the Today Show and all that kind of stuff, was probably not the best for me, because it made me even more dilettante. But along came Herb Friedman about that time, and asked me if I would want to take part in a thing they were thinking about, really reviving the International Geophysical Year and the International Geosphere-Biosphere Program. And so in the early '80s, 1983 I think, I started sticking my toe in that one and became very fascinated by what you could learn about the Earth as a whole if you tied all the sciences together, and if you looked at the cracks between biology and atmospheric science, or between geology and oceanology and stuff, that there was an awful lot to be found there that might be secrets about how the world worked. And in the course of that I became more and more aware of and concerned about global Warming than I had been.

WEART: This was not a concern of yours before that point?

EDDY: It definitely was not, and I must say, the reason I got off on the interdisciplinarity of sciences at that time, in the early '80s, was not that I was so fascinated by the possibility of greenhouse warming. As it was, I was fascinated by the notion of bringing people together from different disciplines and mixing the chemistry and see what happened. And so I was the first chairman on the Academy Committee on what later became the sort of Global Change Program. I did a lot of work there. I set up a new organization within NCAR, who had decided to hire me back.

WEART: Back to Boulder?

EDDY: Back in Boulder under, we called the Office for Interdisciplinary Earth Studies. And about six years or so, five, I did that--

WEART: Oh, it was sort of partly administration and partly, I guess, writing and teaching in a certain sense.

EDDY: Doing that and an awful lot of international pushing and shoving, and trying to get people to come on board in the International Geosphere-Biosphere Program, which, unlike the IGY, is an endless thing that is already been now in existence for ten years. And I think it's doing a lot of good. But mainly the interest was to bring people together. And we organized things up at Aspen. I could be a part of that. And I kept scared all the time, because I was having to learn all kinds of new stuff all the time. That's what makes it fun. And so that's what I've been doing. And now I'm in kind of semi-retirement.

WEART: Now you've withdrawn from all of that, and you're off in Michigan. Tell me just very briefly, how did Consequences,* this journal, get started?
[* A printed global changes newsletter, formerly online at]

EDDY: Partly because I had taken a job in 1992, at the time I remarried, in Michigan. It was a job where it would let me mix with social scientists. That was kind of the last challenge, because we all know how inferior they are and how they suffer from physics envy and stuff like that. And so here was a chance to--

WEART: We can't do global change without them, yeah.

EDDY: We can't do it without them. They were very reluctant to get involved. They didn't like the idea of organized programs. They're a totally different breed of Indian than most of the physical scientists and chemical chemists that you and I know.

WEART: Yeah, you're telling me. Listen, I've spent the last ten years working with the political scientists.

EDDY: Okay, sorry, you know this much better than I. So I went to take a job at CIESIN, which was the world's worst thing, which was a pork barrel.

WEART: CIESIN? What's that?

EDDY: It was The Consortium for International Order of Science Information Network, CIESIN, and had been started by a member of Congress who wanted to dump some money in Michigan. I knew it was terrible. I had been raised to look upon pork barrel as next to incest as the naughtiest thing that's possible on Earth. Barbara and I went there. We both were offered a job there, I as chief scientist and vice president of research, an organization whose annual income was, at that time, up to about 25 million dollars a year and they weren't quite sure what to do with it. It was not so good. And so after a year and a half-- I went there kind of as a missionary to try to convert them and try to wean them away from pork barrel funding and to start--

WEART: Kind of to do something useful.

EDDY: And after two years, I had not converted a single soul. I was kind of frustrated. I had learned a lot about social scientists, respect them all the more because of it. But then Barbara and I said, "Why don't we just get out of here and try something on our own." So we submitted a proposal on our own to work out of our home, which we do, to produce Consequences. And we've been doing that now for five years. And we do it through a little university in Saginaw, which is an excellent school called Saginaw Valley State University, not very far away from us.

WEART: And finally, anything else you want to say about this whole story, anything we missed?

EDDY: I don't think so. I think the whole Maunder Minimum thing probably gave me more attention than I deserved, but it was very good for me as a learning experience.

WEART: Okay, let me cut off the tape now.

Conducted for the American Institute of Physics, HTML version courtesy of American Geophysical Union.
copyright© 2001 Spencer Weart & American Institute of Physics

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