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Courtesy of Chryssa Kouveliotou, credit unknown.
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Interview of Chryssa Kouveliotou by David Zierler on March 25, 2020,Niels Bohr Library & Archives, American Institute of Physics,College Park, MD USA,www.aip.org/history-programs/niels-bohr-library/oral-histories/44493
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In this interview, David Zierler, Oral Historian for AIP, interviews Chryssa Kouveliotou, professor of physics at George Washington University. Kouveliotou recounts her childhood in Greece and her early interests in physics. She describes her studies and political interests as an undergraduate at the National University of Athens. Kouveliotou explains her work at the University of Sussex where she pursued research in optical astronomy. She recounts her work in extraterrestrial physics at the Max Planck Institute and she describes the origins of gamma ray astronomy. Kouveliotou discusses her cultural introduction to the United States and her work at the Goddard Space Flight Center where she studied gamma ray bursts for her graduate thesis. Kouveliotou explains her academic work in Greece after her graduate studies and her research at the Institute for Space Physics, Astronomy and Education where she worked with data from the BATSE project and continued research on gamma ray bursts. She explains her move to NASA headquarters and her current work as a faculty member at GW. In the last portion of the interview Kouveliotou explains her long-term work in the field of magnetars.
Okay, this is David Zierler, oral historian for the American Institute of Physics. It is my great pleasure to be here remotely with Dr. Chryssa Kouveliotou.
Dr. Kouveliotou, thank you so much for, for being with me today. It's a great honor to be speaking with you. And let's just get started right at the beginning. Tell us about your early childhood. Your parents and your birthplace.
I was born in Athens, Greece. My parents belonged to what we call the middle class. My father was a mathematician. My mother was an economist working with the government at the...I have no idea how to translate this, this was the department of the Greek government that approved budgets for the higher education, including how many faculty were supposed to be hired, and all that stuff.
Like a department of labor?
No, she was working in a branch at the Ministry of Finances. She dealt with personnel stuff. Everything in Greece at that time that had to do with higher education hirings was decided from that particular department; they were approving funding for new organic positions in universities. My grandparents from my father's side came from a very small village in Peloponnese. My father was practically the first one, or even the only one in his family, to go away from that village and study at the university in Athens. After he graduated he started a tutoring school in mathematics for high school students. That's what his job was, tutoring students from high school in all classes. High school in Greece at that time was six years. He had rented a building, and he had classes on different levels in, I don't know, four or five rooms. So he was going in one class, solving one problem, going to the other class, solving a different level problem and so on-- Basically, he worked from seven o'clock in the morning until late at night. So in the early childhood, I don't remember a lot of my father. I didn't see him very much. He was working very hard.
My mother was also working hard; it was a different system at that time, she was working in the morning until about two or three, and then she was going back to work, because they had the siesta break, to work until about six or seven. So I didn't really see her too much either. None of them did any household chores or work, other than taking care of it, and as the tradition was at that time, we had a lady, or a young girl actually, who came from a village somewhere in the country, and stayed with us, and she was taking care of the kids basically. She was doing all the house chores. Like an in-house maid. But at that time, the concept was not as, treat her as a maid. She was treated as a person of the family, and in fact my father, when she got married, he gave her what you call dowry to thank her for all that. But I remember her as the person I was mostly in contact with when I grew up. And I still remember her name and I still think about her fondly. I hope she's well, but I doubt she's still alive. So I grew up a lot with my grandparents. Because my sister was born one an a half years later and my grandparents had a lot of time in their hands, and they were living on the top floor of the house, so--
This is your mom's parents?
This is my mom's parents, yes.
And are they Athenian? Your mom is from Athens?
Yes, she is-- she was from Athens, and her father was a well-known lawyer at that time. And he also, we found out after he passed and we emptied all the stuff in the house, that he was also a poet. He was writing poems and he had issued a little book with poems, which we still have, which is quite a treasure. So, my grandfather, who loved me dearly, and so did my grandmother, basically, he took it upon himself to bring me up and teach me how to read, how to count, you know. And this was my first interaction with education, if you will. I mean, my grandfather really taught me how to read. Not that I understood what I was reading, but he taught me how to read newspaper, which was in a very difficult language at that time. It was the high level Greek language. So I could read texts very well, at three or four years old, but I couldn't figure out what it meant.
I was actually a very happy child. Because I had a lot of love and I had a lot of attention; when my sister was born, she got a lot of the attention. But I had my grandparents, and everything was working fine until...he passed when I was six years old, which was very sad, and it was one of the worst times, I can still remember. And then some years later, my grandmother passed, so basically my life changed and I was together with my sister, which was actually wonderful, because we have a fantastic relationship. Even now long-distance, she is in Greece.
My parents whenever they could, they were trying to do things with us like go to the museum, go to excursions. There was at that time a small group of people, like a busload group, who, I mean, you probably never experienced that, but at that time, we had only Sunday free. There was a six day week. And everybody was working--
And is this Saturday, was, was Saturday the Sabbath, the Greek Orthodox Sabbath?
No, no, no, nothing to do with religion. It was a working day, period. So only Sunday was the free day. Saturday was a full working day. And school was working too, as a matter of fact. So basically, we only had one day for rest. I was born, and I mean it as I say it, because at that time, people were born into the religion automatically. I was born into the Greek Orthodox religion. I do not know if that's of any interest, I am an agnostic right now. So I don't really follow Greek religion days. But, at that time, we were actually celebrating without going to church. We were not going to church because Sunday was the only day we could get out of the city, out of the house. So my parents organized, and participated in many organized excursions. All over the country. With buses. In the holidays, we also did that. I mean we went several places in a bus as children. Very few of the participants were children. I think only one more family in that group had children. Most of them were older people, because my father had a 24 year difference with my mother, and most of their friends were closer to my father's age. And they were singing songs, we were all singing songs, that was amazing. I can still remember it. We saw a lot of Greece that way. And I guess I got a lot of contact with my parents that way. That was the best way to know my parents.
When they were on holiday? Is when you spent the most--
When we were doing things together as a family. We didn't, it didn't last very long, because things changed. The economy didn't stay very strong. In the summer what my father used to do is see what the rent in a small house in a village was, and he would bring the whole family there and he would come over the Saturdays, sorry, Sundays.
He was, as I said, a mathematician, and he was assigning a lot of importance to learning. He had a lot of books. I still have them, and one of them was a history of the Universe. And we're talking 1950s now. He gave it to me one day. I have no idea when it was, but I must have been less than seven or something. At that point, I could read very well, and I was writing as well. So basically, obviously, I mean, seven years old, you should be writing. And I was going to the grammar school. It was a private school. The teachers were phenomenal. I think that created the basis of my wish to learn and the appreciation of learning, and the admiration to the teachers, because these people were working as if we were their children.
This is a secular school or a religious school?
No, secular. We never got into religion. My father, my mother-- okay, that's interesting. So my parents had a very good relationship, but politically were about 180 degrees apart. My father was for the king, because we had a king at that time, and my mother was a hardcore socialist. And--
So "for the king" means what? More conservative? More to the right?
Royalist. He was a royalist. He would be for the hard right party. And we had a lot of parties, in Greece as in Europe, right? So he belonged to the right wing, even hardcore royalist. My mother belonged to the left socialist party. They voted completely differently. But they never had any fights. I mean, because...I don't think my father cared in having any fights. He just said, "That's what I believe, and I'm a Christian as well, so that's my belief. Whatever you choose to believe." And he said that to both of us in every choice we had to make in our life. For instance, when I decided to do astrophysics, he said, "I was hoping you would take over the school and tutor in math." Because my sister became an architect, and she had no interest in that kind of direction. And so basically, I said, "No, I really cannot see myself taking over." But he said, "It's your choice." So as far as religion was concerned, he said that again to us. "It's your choice. If I wanna go to church and you wanna come with me, it's fine." And at that point, my mother was saying, "You cannot make them decide now. Just let them do whatever they want." So, she won that battle. So basically, it was a family that was, we had problems like all families, but it was a smooth ride, so to speak. There were no ups and downs and basically love, everybody loved everybody else very much and cared. And everybody supported everybody else.
Now, your last name. Is that a unique name in Greece? Is that from a, a particular ethnicity? From your father?
No. It is interesting. I don't know how much of interest it is to you, but what my father said was, his ancestors came from a smaller village, even smaller than the one that I knew he was coming from. And at that village, they used to keep beehives. And when they came down to the village in the valley from the mountain, because they couldn't survive on keeping beehives apparently, they were called Kouveliotis, because the name of a beehive in the local dialect was Kouveli. The people who were the beehive keepers, practically.
He said that the original name, as far as he remembered, was Tsisios. I've never heard of anybody in the family that was called like that, but a lot of the Greek names are paternal names, the names that come from the father usually. Others indicate origin, they indicate profession.
Yeah. I was asking because a lot of, I thought, a lot of Turkish names end with the "ou" sound at the end, so I was curious if maybe there was a Turkish, or even a, a, a Turkish Cypriot connection, possibly, but--
Well, no, it's not, it's the declination of the name. The declention, I should say, of the name. Kouveliotis is the male, and the nominative. I am Kouveliotou because I am the genitive, and I belong to Kouveliotis. Which means I am a part of him, I belong to him. And so was my mother. So for all males it was Kouveliotis as well. The females were genitive, and the male descendents were nominative.
Now, did you have a relationship with your father's parents?
Minimal. Because they lived far away. At that time, the only way to get there was by train. It was a long ride on the train, which was working with coal. And I still remember riding and getting black there. So we went there once a year, maybe? And then my mother actually wasn't very happy because they were very conservative in a sense that they wouldn't want to let us wear pants, which was too much -- we were less than ten years old, right? And we liked to wear pants, and my grandmother and grandfather there said, "The kids should not be wearing pants, they are girls, they need to wear dresses." And then my mother said, "If that's what you want, then I'll take my kids and you stay with your other grandchildren." And we left….
Now, your elementary school, was that the same school that you went to in middle school and high school? Or did you switch schools?
Okay, elementary-- The system was six years elementary school, six years high school. And after I finished high school, it changed. Six years high school, and three-- Sorry, three years high school and three years Lyceum. But I was six years with the same teachers and the same -- more or less -- kids.
Now, you emphasized, you know, you were far along in your reading from your grandfather. At what point did you start to show an aptitude in the sciences? Did this start to come out already in high school?
Oh yeah. Even before. I started reading the book that my father gave me on the Universe, and how much and how little we knew about the Universe at that time. But they were beautiful pictures even without the Hubble. I mean, most of them were graphics, drawn by hand, but I think that's what started me wanting to do something with the Universe, like astronomy, astrophysics, an astronaut, all that-- All these dreams were created during my six years of elementary school. I mean, at the time I went to high school, I knew I wanted to be a physicist. And from that on, I wanted to become an astrophysicist, because I wanted to do something outside this planet. Basically, I wanted to be an astronaut, I never was able to do that because at that time Greece didn't have any opportunity for this. And I knew, and I still remember the very strong urge to get out of Greece, see the world, travel. Travel was in my blood. I started traveling very early. And I think it must have been from all these excursions every week we were doing. Maybe.
That you were curious?
Very, oh, I am still very curious. I'm an observer. I mean, I'm an observer and sometimes I am an annoying observer, because I can tell people something that I notice and they sometimes can get a bit upset.
Now, this being the 1960s, and I don't-- you know, you can tell me about culturally in Greece, but if you're expressing as a young woman, as a teenager, an interest in becoming a physicist...I mean, as woman were you, did you ever feel discouraged from this? Did you ever feel like there was anything that you had to overcome that, that your male peers might not have? Or did you never feel that way?
I don't know how to say this without sounding, without sounding like I'm tooting my horn. I'm going to say it and, I don't know how it's going to come out. In very blunt and in simple words, I didn't care. In other words, if I saw someone who had this attitude, I would avoid that person, or I would tell that person, we disagree. I didn't like conflict, and I wasn't going there for a fight, but if I understood the attitude of a person, I would say, "That's your belief, and mine is different. And I'm going to do what I think I should be doing, and I don't care what you think."
And you never felt that you were blocked off from opportunities because you were a young woman? You just felt that this, these opinions might have been out there, but they weren't necessarily stopping you from achieving what you wanted to achieve?
The schools I went to did not care about female or male. They were high-level schools, they were very good schools, and their task was to teach the students. So they never differentiated between a female-- Actually, in the grammar school, it was mixed. In the high school, it was female only school. So there was no issue there about all that. There were good teachers, and of course there were bad teachers. The math teacher I had in the first three years in the high school was relatively bad. But the next three years, I had a teacher in math and a teacher in physics who were, oh my god. Perfect. I mean, I still remember them. I think it was actually in the early classes, not in the three upper classes in high school. The first day the physics teacher came into the class, she was talking about electricity and light. And in order to demonstrate, she grabbed a chair got on it and she took down the light bulb to talk about the current. How the current goes through the bulb, how it heats the wire and radiates, and all this stuff. And then she screwed back the light bulb and she said, "Now, you can make light yourself." And she went ahead to explain how this is created. She was a hands-on teacher. She was a physicist, and she understood all the basic mechanisms of physics and she was able to transmit that. And the students were totally, I was totally taken by that. In the first three years, we were all together, we all learned together in the same classes. After the third class, in the fourth, fifth, and sixth, we split into science classes, which were called the Practicum, which basically was the hardcore math, physics, chemistry, all that stuff, with a little bit of ancient Greek, modern Greek a lot, and everything else you can imagine. And then there were the classic classes. I remember we had only 20 females in the science class, and I actually see some of them still. They all did well as far as I know. At that time, the majority was towards the classical studies.
I should say that they all knew my father was a mathematician, and they all assumed that I was going to be good in math because my father was tutoring me. My father wasn't tutoring me on a regular basis. My father was tutoring me when he saw that I had a problem and struggled. Then he would sit me down and explain to me how this is solved. After years of doing this, he practically knew all the problems in the books. He started making his own problems, and he wrote a small book of algebra problems for his students. He also taught me spherical trigonometry, which actually I still remember but not very well, I rarely used it. And he sometimes talked to my teachers, but not very often, but he told me “anything you want, I can help, but you have to ask me”. So I did that whenever I needed help. I don't want to be told what to do. Let's put it this way. I like to do things, and I like to be told that I screw up when I screw up, and everybody I know knows to tell me that -- if they feel like that, they should tell me. But I don't like to be told what to do, and I like to be good. I like to be doing my job very well. So I was driven, let's put it this way, and now, looking back, looking back to this 15, 16, 17 year old, I was working a lot. All day long at school, because we had seven didactic hour school days, from eight to 2:30. With very small breaks, like 20 minute break for lunch and two 10-minute breaks during the day, and then we had a huge amount of homework to do. And we were working sometimes till 12 o'clock at night, and it was really a lot of work. I remember in this part of my life how much I had to work. I got pretty good grades. I was, how do you call them here, valedictorians or something like that?
Yeah. Valedictorian is number one in your class.
Yes, I was actually among the top two or three each year in the school across all sections of my class. There were two classical sections and one in the science studies, and I was top in my class and also among the three top in all three. I was what they called the president of the class in my section.
Now, was the curriculum, was the emphasis on math and science, or it was a full--
Yes. We did a lot of physics. We did a lot of math, like algebra, geometry, stereometry. We did chemistry, we did biology, and then we did modern Greek, ancient Greek, history, religion. We did...home work. By home work here I meant how to sew etc.
Yeah. Right. In America, they say it's "home economics," that's called.
Yes, home economics. Yes. So we did that as well. And basically, well, I remember a joke, but I think it might be a crass joke, that-- It's actually a reality, (laughs) but never mind.
Please. No, no. Please, please. I love jokes. Please.
No, it's not really a joke, but I remember it because the teacher who said that did not realize what she was saying. It's one of these things that become a joke after it's been said. So the teacher of the home economics came in. It so happened that in this class she was teaching how to make underwear. Okay? How to sew underwear for babies. You know, they didn't have diapers, right? So we were taught how to make underwear for babies and how to make them long-lasting, etc. So she got into the class, and what do you call them, knickers?
Yeah, sure. Yeah.
Okay. So, she got in the class and said, "And now, girls, take off your knickers and start working." (both laugh) She meant, take them off the bag and start sewing, but I still remember that because it became chaos in the class.
Now, graduating at the top of your class, the National University of Athens, is this, are there a number of schools that you're considering, or this is like the, the place to be? This is automatic where you want to go?
Okay. When I graduated from the high school, going outside the country for basic studies like the Bachelors diploma, was out of the question. Financially, and also I didn't even know at that time, if I can do it--
That it was an option? There was, you didn't think there was an option to study abroad?
No. To study for the Bachelor diploma. I knew that after I did physics, I would have to go outside, because we didn't have astrophysics in the university, but I was going for physics, and astrophysics wherever I could find it. In fact, in physics, I chose that because there was a class of astrophysics in the last year.
And National University of Athens, it's considered-- Is it an elite school in Greece?
It was the only option for me in Greece, and it wasn't bad then when I got there.
It was the only option for a physics degree, you're saying?
I'm sorry, it was the only option for Athens residents like me.
Oh, I see.
I did not want to go to a different city. And it was the best at the time, actually.
I did not want to go to Thessaloniki, or, I don't even remember all the options to be honest.
So it was kind of the best option and the only option, in a sense?
And the only option for me, yes, you're right. Yes.
Now we haven't, you know, in the early, late 1960s, early 1970s, there's a tremendous amount of political upheaval that's going on in Greece at this time. You know, the invasion of Cyprus, the, what's going, you know, I mean all, all kinds of things are going on. Did these things affect you or this was something where you, you were sort of in your own bubble to this?
No, I was not in my own bubble. I'm surprised you bring it up. But this is a big part of my life as well. And, okay, I wasn't planning to discuss this, but let's see how this is going to come out and how much of it should go in there, because...Okay, so we had a junta in Greece, okay? And the dictator, Papadopoulos, had also, because he realized how important education is, he had squashed education. I got in the university -- the first year it was relatively smooth, and in order to get to the university, you'd have to take exams.
And first year university for you would have been what? 1970? 1971? You graduated in '75, so if it's a four-year program...
Yeah it was either '70 or '71...I think it was '71. In fact, as I said, we had to take intensive tutoring classes and then take the general exams to get into the university. There were about 100 physics students admitted in my year. 12 women. There were only 12 women, and I think I was number ten overall or near that. They published the lists of the admitted people outside the ministry door. They stuck it outside the door, so I started from the bottom and as I was going up, I still remember thinking, "Oh my god, I didn't make it, I didn't make it." Until I started screaming and everybody was screaming with me. Anyway, there was a group of very good friends all my university years. I still have contact with a few of them. And basically, the first year we were agnostic politically. We were just going there because we wanted to do the physics and learn. And it was okay in that sense. After the second, third year, there was a lot of upheaval, as you mentioned, starting from a lot of incidents that happened, and I was part of all that...I changed, my life changed completely in that time. We used to be girls that dressed up to go to places. It was blue jeans after that, until now, practically. We were part of the resistance, in a small way. And we were in the group of the students that occupied the law school. In fact, there is a picture of me at the top of the law school cutting my long hair, which we burned so that we could get out without being recognized. And then we went to the Technical University which later was invaded by the tanks. But my father, who had issues with his heart and was diabetic, he requested that we don’t go there at night, every night. Because he didn't want us to be blocked there during the night, because usually it's during the dark of night when the junta did all the things that they shouldn't be doing. And so my sister and I honored that request and we were home when the tanks went in. We couldn't get back in at that time. I don't know if that's good or bad, but I still feel bad of not being with my colleagues at that time. Anyway, my father was very happy to have us home.
What did you feel like you were protesting against exactly? Was it academic freedom that you were worried about?
No, not only academic freedom, freedom in general. Because it was a dictatorship. By 1973 we did not even have the king anymore, the king was ousted when the Greeks voted that they don't want a royal democracy, they want a presidential democracy. The fact that the tanks entered the Technical University, killed students in November 17, 1973, that became the starter of the whole country’s revolt. All the parents and the taxi drivers, they were driving around the Technical University trying to make sure that the kids could get out without being arrested. The parents were making blockades. Most of the country revolted after that. This was the beginning of the end. And we got Karamanlis in 1974, who was in France at that time, to come and take over the Greek Government. And of course, the last year of the university wasn't really a teaching year. We took over the university. The students did. And we were teaching the classes. I mean, I was teaching one class to my classmates, and other classmates were teaching other classes to the classmates, so--
Now, where, where was faculty at this point? Had they fled?
No, we had blocked the university and we wouldn't allow them to get in. Because they were part of the system. Some of them were not, but they were afraid to say they were not, so they stopped coming because we had occupied the whole building, so they couldn't come in anyway.
Did you ever get arrested? Did you ever get in trouble with the authorities?
I didn't, but very close friends of mine did. They were arrested, they were tortured, they were beaten. And, and then after the junta fell, they were being released.
I wonder if you thought about what was going on in Greece within the larger context of, you know, the Cold War, the crisis with NATO with regard to Turkey and Cyprus. Did you see these issues in more global terms, or did you understand them as national Greek problems?
Well, the issue with Cyprus was affecting Greece for sure. Cyprus at that time was Cyprus. Even my colleagues who were from Cyprus, when somebody was asking, "Where are you from?" They would say, "From Cyprus. And I'm a Cypriot." This was a different country at the time, right? Then, of course, it became what it became, but the bottom line is, we understood Cyprus to be an independent country, and that was not what happened after the invasion. So we knew what happened when the Greek army tried to take over Cyprus unsuccessfully for many reasons. I'm not going to go there. And the whole thing became the reason of course why the junta fell in 1974, because there was no way to support the government, the junta government, internationally at that time. We were very well-versed with the Greek environment, and with the international environment. We were always aware of Turkey, and Cyprus. We used to hear Deutsche Welle, BBC, in the night, in low volume so that nobody else could hear us. And I still remember Deutsche Welle in Greek. I mean, this was amazing. That was the only information source we had. And the whole family was gathering and listening to these two networks. I met Netherlands people, Dutch people, who came and supported us, because they were very proactive, came to the university and helped us.
All the parties had the youth groups of the party. And the youth of the party was ruling, so to speak, in the universities, where all the young, educated, or going to be educated, people were. And the first education we got was in politics during the first couple of years. The culture differed in different parties, and so we got to choose where we wanted to be. In what party we wanted to be. So, basically, it was a very polarized in a sense, environment, because the extreme right did not collaborate with the extreme left, but in the end when the army got in, they all went against it. So there was no difference there. It did affect a huge amount of my life. I'm sorry, I should say, it did affect a very formative part of my life, and it did affect a lot how I think about authority. That's why I said, I don't like to be told what to do, I guess that's probably where it stems from. But I mean, it did, it was a very, very determining period in my life.
Now, amazingly, it seems like you graduated more or less on time.
You know, in 1975. How, how on earth were you able, with given everything that was going on, how was it that you were able to complete your coursework on schedule?
Because we were all studying in groups. As I said, we didn't want to be stuck. We wanted, I wanted to get my degree and get out of the country to do a PhD. So...
So you knew, already you knew that leaving would, would be an option for you, in a way that you did not know that as a high school student.
I knew as a high school student I wasn't going to stay forever in Athens. I was going to see the rest of the world. When I started studying, I knew there was no way I could complete the studies to the level I wanted, being in Greece. So for me, going out was not a question. It was the next step. What I did not know was that I was going to stay forever in the United States. That was a different story. And--
Now, about your, your physics education at the University of Athens. Were you exposed to all of the, the major sub-fields of physics? Were you concentrating on a particular area? Did you already know that astrophysics was what you wanted to, to pursue? How, how broad was your vista?
Okay so in Greece, the higher educational system had different directions and there was physics, math, chemistry, and so on in one College with the STEM part of the education. When you were doing physics, you did every possible part of physics. In every level in four years. That was a four-year degree. And you ended up with a Bachelors diploma. And basically, you didn't have to choose. All that was completely set, the curriculum was set. You were also doing chemistry, organic and inorganic chemistry. You were also doing, I'm trying to remember, mathematics, obviously. Math, different types. Statistics. All of these classes, we did biology as well. They were mostly math-oriented and -based. We didn't have the variety we had in high school. This was a very physics-oriented degree. In the very last year, we had astrophysics. And that's when I decided, okay, I like it, I love it.
The astrophysics professor was educated in England, so he was very up to the research, he was an excellent professor. And I liked him very much. I was pretty good in his class, because that was my favorite. I did a small project with him, and being confident of myself, I went to him and said, "Okay, so now I'm graduating, and is there a place you would recommend that I would go to do my PhD thesis?" Him having also studied in England and outside the country, I figured I had a lot of affinity with him, and he would know where to guide me.
And he, he was Greek?
He was Greek, yes.
He was Greek, okay.
I found out later that there were many women astrophysicists in Greece, because at that time this was something like, for instance law, which had more women.
You mean astrophysics is actually unique in how many women are, are able to, to join the ranks?
When I was there, yes. There were a lot of women to compare to other areas that were math and physics.
So he was giving you friendly advice?
Advice, oh yes, absolutely. Not only friendly advice, he was caring for me.
Okay, so you get this advice, you graduate from, from National University of Athens. The world now seems to be available to you. What, what are your options, and how do you eventually land at the University of Sussex?
Okay, so I was working with one other colleague writing the last year thesis together. And my colleagues also were doing their own thesis, a diploma, at the very final year.
Oh, so we have to stop there, then. What was your thesis?
It was one year project in optical astronomy. We were actually working on spectra. Optical spectra from different stars, and were classifying them. I was working with a colleague who is now a professor at the Technical University in Athens, and we had to finish in a certain time, December ‘75, so that we could graduate and move on to the PhD start in the fall. So he pushed, and I worked with him, so we finished in December. We got the degree at the beginning of 1976, I think. But because all the courses start in the fall, I had to spend about five or six months doing nothing, which nearly killed me, because I just couldn't stay doing nothing, so I took classes in Greek and English typing and stenography. And then I was reading books and filling applications.
This is a parenthesis, when I finished grammar school, my father got me a teacher to learn English, and these were private classes. A lot in Greece was on a private level at that time. And she was very good, I learnt the grammar very well, but I didn't know how to speak, so, my father had a friend whose child he was tutoring. He was also doing personal tutoring. And long story short, he brought me in contact with a Greek-American lady, who was but two years older than I was, and we arranged to go out for coffee and talks. So that's how I started talking. And she helped me a lot. She was excellent. So by the time I finished the high school, I was speaking very good English - British English, though, because she was from England. And then, of course, I had already started traveling when I was at the university. As a first year student of the university, we were able to go to Vienna - we took the train and we stayed all over Europe. So I had some experience. We went to Egypt. And got sick tremendously, but we were fine after a month. And then we traveled all over Central Europe, sometimes slept at the train stations, because the train would leave at three in the morning. We slept in youth hostels. So I had seen what it looked outside Greece, and I thought England would be my favorite at that point. I had been already in England and, I spoke the language. In high school I started learning German as well. So I had two languages I could work with, although my German wasn't as good. I knew it just theoretically -- I couldn't speak it very fluently. And so I wrote applications at the University of Sussex and wrote applications at Max Planck Institute in Munich. And they both accepted me. But the difference between the British acceptance is that it would cost a lot of money, and with the German acceptance they would give me a scholarship for the whole time. So my father said, "You know, I think you should go to Germany." And I said, "I would love to spend at least a year for a Masters in England". I liked the classes they had there. They had very good professors. And it was a university, right? Max Planck wasn't a university, I didn't even go to the university there. I spent all my time at Max Planck and not at the Technical University of Munich, because I did all the research at Max Planck. I didn't attend classes.
So my father said, "Okay, I will help you for a year, but that's as much as I can do." He had to take a loan in order to support my studies in England. I certainly appreciated that.
Now did you ever, did you ever consider the United States for graduate school, or that was, that was too far away?
That was too far away and it wasn't an option for me. I mean, I was more enamored, so to speak, with--
With Europe. And I wanted to basically stay in Europe as well. I mean, I wasn't looking other than visiting the country. I wasn't looking into living forever in the United States as I am doing now. Because I felt that it would be much more difficult to interact with my family and travel wasn't as easy as it is now, of course.
Sure. Now, the decision, the decision between Sussex and the Max Planck Institute, is that because...in terms of your focus on astrophysics? These were really the two places to, to study for this particular degree? Or were you thinking more generally that these were just simply good physics programs?
Well, first of all, I wanted to do optical astronomy. And the classes in Sussex, had also connection to the Royal Greenwich Observatory, which is a historical place. And I thought that it would be a great idea for me to go there, especially because I thought my professor’s education was also from there, as he was talking about it. And I looked at the curriculum and I liked the classes. I don't even remember if I applied to other places or if I were accepted in other places. I honestly do not remember at all that time. Anyway, I got the letter back from Sussex with the acceptance, and I got the letter from Max Planck. My decision for Max Planck was -- because I had not clarified that I wanted optical astronomy – based on that I wanted to do a thesis. And I did not know that they only had high-energy astrophysics. They didn't have optical astronomy there. Also the fact that they were subsidizing me. In a way, that was a decision that was made for me, because I didn't have money for the rest. So, I did the thesis in Sussex. And the next year I went to Germany.
That was very generous of your father to take out a loan, especially when you had the option for a free education. He must have really believed in you.
He did. And he believed in my sister as well. He believed in his children. I think he was an amazing parent, although I didn't see him very often. He really was a very mature person, in a sense that he knew how to handle kids. He lived his life next to children. Kids. All his life. He was a very beloved tutor as well.
So you were in Sussex for only the one year? It was a one year program.
It was like about nine, ten months.
Now was that unique, for an entire Masters degree to be compressed into, into a, such a small amount of time?
That's a good question. I never perceived it should take longer than a year. Because I already had accepted, so I had to go to Germany, so I finished. That's it. I mean--
Right. Did you do a thesis? At Sussex?
I did. And actually, I loved it very much. My advisor was a visitor. Peter Wehinger – he was in Sussex with his wife. And there were--
Where was he coming from?
United States. He was American. I believe he passed. They were visiting for a year -- he had some data that he already had worked on, and he said—analyze the data. So I worked on that. The student in Greece with whom I made my diploma with, was also accepted in Sussex, he was doing his thesis with the wife of Peter. And so, he was working with the wife, I was working with the husband, and we had a lot of discussions together. We were both also renting with two other students one house in Sussex. In Brighton.
Ah, okay, Brighton.
Yes. So we spent a year there on a very, very short budget. I remember we spent eight pounds a week each for food. Because all the students put down, all four of us put down eight pounds a week and we bought stuff and we still could live with eight pounds, and--
Were there many international students in the program, or it was mostly English students?
No, there were many international students. There were also some English students. There were I think more international than English. There were at least in that program three Greeks that I know of.
And you had a good experience at Sussex? (
Yes.) It was a nice time for you?
I loved it. I got to know the British culture more. It was a very, very nice experience. We loved it.
Now you knew the whole time that you were going to, to Max Planck?
This was the plan from the beginning?
So the idea was, you would do a masters, a terminal masters at Sussex, and then just go right into Max Planck for the PhD?
I went back home in Greece, and then I flew to Germany. And there, I found out that I couldn't do optical astronomy anymore, because they didn't have it and they wanted to give me the opportunity to go and do optical astrophysics somewhere in Germany, but I already had found a place to stay, I had arranged everything. So they told me to visit all the groups and see which group I can work with and choose. I went and talked to all of the groups there. And the gamma ray group sounded more promising because they also had an opening for an interesting thesis as well.
Now, the gamma ray group is one group in the extraterrestrial physics program? How did that work?
Well, the extraterrestrial physics was not only the program, it was the Institute of Max Planck for Extraterrestrial Physics, it was the whole Max Planck, okay? At that time there was the X-ray group, the gamma ray group, the heliospheric group, and the theory group? I'm not sure, I don't remember all the groups, to be honest with you at that time. So I got into the gamma ray group, because there were a couple of people who were extremely nice and very friendly and they were working on something I would like to work on. In fact, one of them already told me that basically he was running a balloon experiment, and he could get me there as a graduate student to start the program analyzing the data. Gamma ray bursts were at that time just being discussed. He expected to detect gamma ray bursts with this balloon and he wanted me to read about gamma ray bursts before the travel -- actually this was going to happen in Australia, in Alice Springs. There wasn't much to read, but I read everything I could find. Theories and reports of one or two events. And so I decided to join that group. They were all very nice people; the thing is, I started talking to them in English. Obviously, because I was much better in English. And my advisor who was the director of the Institute at that time, Klaus Pinkau, he was very annoyed that I wasn't speaking German, so the second year he directed all the members of the Institute that interacted with me to never talk to me in English anymore. Only in German. Which made my life horrible, because I couldn't. But in the end I learned how to speak German, so I'm grateful to him. So basically, I worked for half a year developing programs how to detect gamma ray bursts, how to look at the data and select events, and all that stuff.
How much coursework were you taking? Were you in classes at all?
None. None. This was pure research. That's why I wanted to take the previous year, because there was a lot of coursework in astrophysics in different areas, and therefore, it helped me to do that. I knew there were no courses in Germany. You just did the research. I mean, in the Max Planck Institute. So-
Now, were there areas, you know, with the lab work that you were doing, were there things that you, you didn't know that you would've benefited, had you taken a particular course, that you were teaching, that you had to teach yourself? Or did you feel like you were pretty well-prepared with the coursework that you had already taken at that point?
I thought so.
I mean, for example, what did you know, what did you know of gamma rays before you got to, to Max Planck, for example?
The very, very principle. What they were basically. And gamma ray astronomy, and in particular Gamma Ray Bursts, was taking slowly off, actually. It was just the beginning. So I learned as it went. And I read everything I could at that time, learned what it was,
Why did gamma ray astronomy start at this time? Was there a particular technological development or a discovery that happened? Why, why then?
Well, it didn't start when I was there! It started in the 70s, I think. Phillip Morrison wrote the first paper “On gamma ray astronomy” in 1958; he predicted what to expect to see in gamma rays from astrophysical objects. It necessitated space missions. The gamma ray burst phenomenon was discovered with the Vela satellites. It wasn't something that could be done easily, because you needed to have space missions to work on X-ray, gamma ray astronomy. So the whole thing was booming slowly with the gamma ray bursts coming up. In '79, there was this fantastic transient that was part of the magnetar story that I will discuss later. Max Planck had a whole team on gamma rays and they worked on many missions. The International Sun Earth Explorer-3 (ISEE-3) was the mission I ended up working with. The reason being that when the scientist with whom I was supposed to do my thesis, found out that the crane that lifts the payload for the launch, the payload that's connected to the balloon, was too small to lift it --
Yes. The one they had in Alice Springs. So he found out that after I had done all the previous work and everything, we could not go there. And he decided to fly from the United States from Palestine Texas, if I remember correctly. Anyway, the bottom line is that I was the second PhD student in this group, and the first PhD student had collected data from the balloon flight the year before in the United States. That's why they were going to Australia this time, and they were going to put another PhD student, namely me, on these data. But once they had to go back, these data went to the same graduate student, obviously. I couldn't compete with another student. So there went my whole project. After a year or so of study, I was without a project. And that was devastating, because I had started to like what I was supposed to do. I was actually looking into changing entirely course and going towards a different direction, and Max Planck was extremely helpful. The director was very helpful, everybody was helpful. They paid my travel, they sent me to a couple of other Max Plancks, to interview and see what they were doing, and see if I wanted to move to them. They would set the timer again exactly when I moved to the new place, and they would, you know, pay me again for the three years. So I went and visited several places, and I came back, I wasn't satisfied with any, and I was musing in my office one day, what on Earth am I going to do at this point?
And then someone knocked at the door, and Dr. Hovestadt, the leader of the helio group came in and said, "You know, I heard you have been reading on gamma ray bursts. We are flying the International Sun-Earth Explorer-3 (ISEE-3). We're part of the spacecraft mission, which has three piggyback experiments." One of that was Max Planck, and the other one was Los Alamos, and the other one was the University of Chicago. These three experiments, basically were taking advantage of the newly-started gamma ray burst field, to detect gamma ray bursts with this mission. They were flying just as piggybacks to take advantage of the existing mission. So he said, "You know, I actually hear you've been reading up on that, and you're our only expert in the institute about gamma ray bursts. Would you like to move into the group and actually work on the data of the Max Planck detector?" And I said, "Oh, yes!" That was really one of these miracles that happened when you're totally out of ammunition, and you're thinking you're going to sink. All of a sudden, there is the raft there. So basically, it was fantastic. I was very happy, and that started my travels to the USA, because these data came down to Goddard Space Flight Center. So I had to go to Goddard and learn how to get the data, analyze the data, understand how this all worked, so the first year, I went for a month and stayed with the department secretary who hosted me. Extremely nice person. So I stayed there for a month, and then I went there again the next year for another month. I met a lot of people.
My first interaction with the American culture is, the night I arrived, I rented a car and I went to College Park, and I had dinner and the dinner plate came and it was like, huge, and I was thinking, "This, I can feed my whole family with." I mean, in Greece, a whole family of four would eat that.
Now what year is this, that you're visiting at College Park?
I think it's '78 or close to that.
'78 plus or minus a year. And I look at this, and I said, "Okay”. I ate as much as I could. And then the waitress comes and says, "Do you want a doggy bag?" And I said, "What's this?" And she said, "Well, do you want me to put it in a box, and you can take it with you?" And you know, this is a different culture. I was totally insulted! "No, how can you say this?" I mean, do I look like, you know, a pauper?” (both laugh) It just was a completely different concept -- In Greece, people would leave everything, all the leftovers, at the table. There was no other way. Now, they don't, by the way. The culture has adjusted. But when I grew up, you ate as much as you wanted, and whatever was left, stayed on the table. Because you wouldn't want to show that you needed to take that home, you know? It was that kind of culture.
Welcome to America. (laughs)
How long did you stay? How long were you in College Park for?
I was a month for the first time. And then I went back the next year. I made very good friends there, and I have links with Goddard that I actually still enjoy. I went several times back there after I finished, and went back in Greece – and also in my first sabbatical. And although I spent over 20 years, 25 years, in Marshall, several times I found myself talking about Marshall, but calling it Goddard, you know? It's strange, but Goddard was my first experience with NASA. And that time, when I spent the first month there, I said, "I want to become a NASA employee." That, that was--
That was it, that was the dream.
That was it, yeah. yeah, I just thought it would be the top, there was nothing else I would like to do. That was my dream, okay?
And now when, when did you settle on your thesis topic? Back at Max Planck?
The day that the guy said, "Do you want to join the team and study gamma ray bursts?" And so gamma ray bursts, it was.
Now, can you translate your thesis title, "Observations of Fast Transient Gamma Ray Phenomena," can you translate that a little bit for our broader audience, what it was that you were working on?
Yes. In the sixties the United States built the Vela satellite network, and that was really to make sure that the 1967 nuclear test ban treaty was enforced. And what they were looking for were nuclear explosions from nuclear bombs. The satellite system was successful -- I don't know what they did as far as the classified data were concerned, but all of a sudden, they started recording explosions that didn't come from Earth. They came from space. They couldn't figure out where they were coming from. They were not coming from the solar system, they were not coming from the Earth, they were not coming from the Sun. And they were very similar with the nuclear explosions. They were emitting gamma rays, lasting tenths of seconds. Now we know, they last for milliseconds to thousands of seconds, but at that time with these missions, you could just get a few events. We called them gamma ray bursts, because they were impulsive transient phenomena, they were coming in bursts. In other words, they lasted a very short time, and they emitted predominantly in gamma rays, which are high energy photons.
The electromagnetic spectrum comprises photons across the wavelengths, and the highest energy photons, with the smallest wavelengths, are in gamma rays. There are not as many as the optical photons, which have less energy, but they have a huge amount of energy compared to the optical photons and obviously they are not observable with the naked eye, because we don't have that capability as humans. We are only seeing in a very narrow band, the optical band. Gamma ray bursts required specific instruments to be detected, and scientists, when they realized that we were talking about a new phenomenon, they started building them, and we were trying to understand what kind of mechanism produced these gamma ray bursts, where they were coming from, what kind of object emitted these gamma ray bursts. We did not even know their distances and their origins, in other words where these were emitted from across the Universe.
Yeah. So these gamma ray bursts became the mystery of gamma ray astronomy. We did not know what they were, and everybody, when a new phenomenon pops up, every astronomer goes after it. And because there were too few, you know, you couldn't have all the astronomers who do gamma rays play. But everybody wanted to go after this new phenomenon. In particular, because in March 5th, 1979, a tremendous explosion in space happened. The March 5th event, which is historic. It was extremely bright, extremely short, and it was detected with everything that was in space, and it was at that time, considered the typical gamma ray burst phenomenon. And that really pushed the field very forward, because basically, it was such an energetic event that people were starting to seriously question what's the origin of that thing, and where does it come from. If it's in our galaxy, it is much less energetic than if it is outside our galaxy. And people could not accept that it would be as energetic as it should have been, were it to come from a far-away galaxy. They didn't think nature can produce that kind of energy, because this was basically the same energy that was produced in an explosion of a supernova.
So if you say "nature" couldn't produce it, what's the other option?
I'm sorry, I meant we did not know how nature could produce them, not why. How nature could produce this kind, this amount of energy, so often. Because we saw one a day, more or less. So we were trying to figure out where it was coming from, and what could make it. We knew that supernova explosions basically can't produce gamma rays like that. Energetic events like that. And we couldn't see any supernova at that time together with the burst. So we did not know their origin. We did not know their distance. We did not know their production mechanism, so this was very fertile ground for all astronomers who want to tackle a new phenomenon to start, you know, working on how to approach this. So obviously, this was a very motivating event.
But I also have to tell you, since I actually grew up in this culture, that the gamma ray burst field was a cutthroat field at the beginning. Because we didn't have a lot of events, we didn't get a lot. There were not gamma ray burst-dedicated satellites for that. And it took several years beyond that, in 1990, when the Burst And Transient Source Experiment went up. BATSE was on the Compton Gamma Ray Observatory, which detected 2,704 gamma ray bursts in 10 years. Before then, we were counting on the Russian satellites, the Prognoz and the Venera satellites, the ones that were going to Venus. They weren't finding many gamma ray bursts, but they were not built for gamma ray bursts. So we were using whatever we could find, and that's how we discovered magnetars, by the way. Anyway, so just to go back, I did interact on a regular basis with Goddard. I completed and defended my thesis on explosive transient events -- gamma ray bursts, in '81, September 14.
How did you see, what was your principle contribution to the field with this thesis? How did you understand that?
That was the first thesis in gamma ray bursts. I remember--
The very first? The very first thesis?
The very first thesis in gamma ray bursts, as far as I know. And the knowledge we had of the phenomenon at that time was minimal. I mean, all I could do was phenomenology, some research for variability, and some spectral analysis. But that wasn't even very good, because we didn't have a lot of high quality information on that. So I don't know that the thesis itself today would be anything else but of historical value. Because right now, we have, I mean, I've worked a lot on gamma ray bursts after that. And did a lot of work. What is--
How, how broad was your purview? In other words, did you see your research simply as understanding gamma ray bursts? Or did you see understanding gamma ray bursts as really connected to understanding larger questions about how the Universe works?
Absolutely the second, but I did not know what I could do with this stuff. We did not know at that time what gamma ray bursts were, so we were doing detective work, basically.
And the limitations were, in not knowing what gamma ray bursts were, the limitations were technological, they were theoretical, they were just a, like a, there just needed to be more work on the subject? What were the limitations?
Observational. In order to understand the energetics, we needed to know their distance. Because you don't know how much energy a source emits unless you know its distance. You needed to understand their durations. You needed to understand their spectra. You needed to understand their distribution in the sky. In other words, are they coming in clumps in the sky, or are they isotropically distributed in the whole sky? Can you associate them with a specific cluster of galaxies? Or better yet, is there a place in the sky that has a preference in producing gamma ray bursts? And above all, what is the origin of the central engine of the gamma ray bursts, which we're still, I should say, trying to understand. So basically, there is a lot of mystery associated, or was a lot of mystery associated with the phenomenon.
So with observational limitations, the idea is, now that you know what you're looking for, you just need to look for it, and that takes time? That that's the idea?
So we looked, okay, so let me tell you what our quandary was. What our problem was. We had a detector on the sky, which observed in gamma rays. So when you look at the gamma ray sky, any transient that comes up in gamma rays, you're not going to miss it and you're not going to confuse it with another transient. Because they are a few and far between in the whole sky. These transients come once a day, or twice a day, and basically, if they light up, they are very bright in gamma rays. So there is no way you can miss it. If you take an optical detector and look for a transient, you are going to see, I don't know how many transients, maybe thousands of variable sources with the future most sensitive telescopes. So gamma rays were the ideal wavelength to see transients, but then you had to find out the properties of the same phenomenon in all different wavelengths. Because optical would give you, for instance, lines. Spectral lines. Because the light that comes with the gamma ray burst would go through matter and there would be absorption lines, and these absorption lines would be shifted from their canonical rest frame, or laboratory frame wavelength to different wavelengths that would be associated with a redshift, a distance, of the object that emitted the radiation that went through the circumstellar or circumgalactic medium, and absorbed the light. And my--
When you said "laboratory frame," what is laboratory frame wavelength mean? What is "laboratory" in this context?
"Laboratory" means "on Earth." Without the effects of the accelerating universe.
So if you have a line that's emitted from the excitation of a particular element, and if you detect this line where you are on Earth, it's emitted in a certain wavelength. When this line in emitted in an object far away, this line is Doppler-shifted. It's not at the same wavelength. By measuring the shift, you can identify the distance. The cosmological distance of this object. From you, from Earth.
Does it make sense?
Okay. So if these events came from a galaxy far, far away, then the actual line would not be in the rest frame, or the frame of the laboratory. We call it "rest frame" - basically, it's not moving, it's here on Earth. Or "laboratory frame" because you observe it in the laboratory. As opposed to the source frame, right? The source frame is far away, moving away from us. The cosmological redshift. So you can measure it and you can identify the actual distance, and then you can identify the actual energy. Photon energy that's emitted from this object. But we could not find the optical counterparts of the gamma rays, as we called them. So you had the gamma ray burst, which is emitted from an object, and we hoped that the same object at the same time did not only produce gamma rays, but it also produced X-rays, optical radiation, radio, and other parts in the spectrum. We did not know what it took for us to actually measure the other emissions. For in--
Why did you, I'm sorry, why did you not have any other detectors besides gamma ray detectors?
Because we did not have a mission that had everything on it and could go at the same time or with very little time difference on the same area of the sky, and identify the optical counterpart or the X-ray counterpart. The radio was done from the ground. So some radio was found later, much later with VLA, and obviously, the most important thing is that when you located a gamma ray burst, the locational capability that we had, provided large areas of the sky, via triangulation; we had three spacecraft on, around the Earth, or even in interstellar space, and they had piggybacks which basically means one detector. So you have the wave of the gamma radiation sweeping through the solar system. One detector is sitting here, the other detector is sitting there. The wave arrives first here and then goes past the next detector. It's like exactly the triangulation system we use to find out where a signal is transmitted from in cities. So you could triangulate with combinations of detectors. With two you could do a ring. With three, you could do a cutout of the ring, and with four you could make the area smaller. However, it was several degrees, square degrees. There was a huge amount of optical objects in there.
So we looked at all that, but we couldn't find anything because first we needed to do the triangulation, so it took time to identify the general area of the sky, then we had to send this to the optical observatories and the optical observatories would have to raster this area to see whether there is a transient. Of course, they found a lot of transients, so we didn't know which transient was ours, and some of the telescopes didn't even go there, because they had to scan a huge area and would take them a lot of time to go through it. So the first years when I was at Marshall, when we worked with BATSE, and we got an alert on a gamma ray burst detection, I was on duty for a couple of years also getting up in the middle of the night to check when a trigger came. And I was locating it, roughly, and I was calling Chile, I was calling Keck, I was calling in, observers, asking for observing in that part of the sky, with wide-field instruments, but it took hours, maybe days sometimes, to go back. We didn't realize that we had to be there practically immediately. And so we never managed to get the optical counterparts. The same situation was with the radio telescopes. They needed a much smaller area in order to go look for the counterparts, so we had a collection of gamma ray bursts, but no counterparts.
Now, the limitations that you're dealing with, did you recognize them at the time, or is this you thinking back in terms of the advances in the field in the interim, that you realized? Or did you know at the time, you recognized these limitations?
We recognized the limitations in not being able to locate the source in a very small area, so that we could go and observe. We thought that maybe, at least I thought that maybe the brightness of the gamma rays would be commensurate with the brightness in the optical, so we might be able to see it if something just popped up in the optical and blinded everything. And we were thinking, this is going to be something that will last for a while. All of those were actually correct, but the bottom line is, it has to happen, we have to look, immediately practically after the gamma ray burst is detected.
Now, are you relying on, I mean is this basic deductive reasoning or are you relying on some fundamental principles in physics that tell you it's got to be like this?
As a hindsight, there are some fundamental principles, but we were not relying on that, because we didn't even know what a gamma ray burst was, so I mean we didn't even know what the engine was that drove the gamma ray burst.
Right. So this is really more like detective work at this, at this point.
It was absolutely detective work. We were all determined to find out what on Earth this was. And I had to wait for a long time to come to fruition. I'm skipping a couple of years, a couple of important parts, right now that I may want to go back, talking about magnetars, but I'm talking only about the gamma ray burst phenomenon. After I graduated, I went back to Greece...So, do you want me to, to very quickly say a couple of things that I wanted to tie together later?
Yeah, well, well, let's go sequentially. So if you're still working with, if we're still talking in your dissertation years, then let's stay with that before we, you know, go on to your time at Greece, in Greece.
Okay, because basically, you asked me what the gamma ray bursts were, and there is a whole story to be told about that. But that can come later.
Right, yeah, let's keep it historically sequential, that's fine.
Okay, so...So I am working on my thesis in Max Planck. I have collected all the data that I was given. I'm writing the thesis, and I have to defend the thesis. I found a lot of support from one of the theorists, in Max Planck Institute, because I also collected data from the Sun, because I didn't have a lot of gamma ray bursts, but I had some solar flares, so I also collected solar data. And so I published my thesis, and I defended my thesis as well, in '81, and--
Who was on your committee?
My advisor, Professor Klaus Pinkau, Prof. Joachim Truemper, who became the director of Max Planck after Pinkau. And there is one more, external, I don't remember the name to be honest with you. There were three, three people.
But because this is such brand-new stuff, this is a unique situation where you're really teaching your professors. You know more than they do.
Yes, that's true. So first you did, you give a, if I remember well, I gave a lecture and then they take you apart and they ask you general questions, and I think it went okay, because I got a 1, which is “sehr gut”, which is pretty good in the, in the--
I'm not sure if it's suma or magna, which is one of the two, I'm not sure. I forgot.
Suma is higher than magna-- Suma is higher.
Then it was magna.
It wasn't with special honors, but it was magna cum laude. But it wasn't actually described as that. It was sehr gut, which is also the same, but in German. Here is another side story. When I got the job in Greece, I had to translate my degree from German to Greek. I was still in Germany, so I went to the gate of the Lufthansa Athens flight in Munich airport, asking if I can give this, because it was urgent, I can give this paperwork to the pilot, and my sister would come and find the pilot. This was the time when people had that kind of interaction. I don't know, it may sound outlandish here, but it was easy to do that. So I went--
The pilot was your courier, no problem.
Or the flight attendants, right? So I went there at the entrance. Of course, you could go up to the door at that time.
So I found the flight attendants, and said, " Can I please ask you to take with you this?" And in order to make sure that they know what this is, I showed them that it was an envelope and a piece of paper -- I said, "This is my degree, and I need it translated, because-- very urgently, because they're going to hire me there, and they need to know, I have a degree." So they took it out, and they started--
You mean in order, in order, in order for them to hire you, they need to understand what it was that you were working on, and that's why it had to be translated.
The degree itself had to be translated to make sure that this was a PhD degree, to confirm that I had a PhD, okay? So they pull out the PhD, which is a piece of paper that says the university, Technical university, blah blah--
The diploma, you mean the diploma? Right.
The diploma, yes. That's what I mean, the degree, the diploma. And they look at it and they say, "Oh, she got a sehr gut! Look at that, this is the first sehr gut I see in a--" It turns out, they hadn't seen many. They were just talking about that, they called the others, and they all looked at the degree, and I'm saying, "All I want is that translated, can you please bring it to Greece?" So they were very nice, extremely nice. So they brought it to Greece, my sister waited for them, they gave it to her, and she fixed this, I mean she took care of that. So--
Now, we haven't really talked about your, your decision-making process when you defend. Are you, like, do you want to go back home? Is that the idea? Are you thinking about going elsewhere? You're homesick, this is like really what you want to do?
I was not homesick. I wanted to go back because I got an offer to be hired from the physics professor at the University of Athens, my alma mater, in the physics department, as soon as I graduated. So I went there, interviewed, gave a talk. They were all very happy, and they gave me the job -- The system was different at that time. So I got the position that was something like a high level lecturer then, but not called that way. There were the professors, the top, they were ruling everything. And then they had this level, which was not permanent. And then the assistants. So they offered me the position. And I said great, I'll go back and I'm going to contribute as much as I can, because this is my alma mater. I wanted to go back, to do something for my country…
You wanted to contribute both to your country and to your department?
Exactly, I wanted to give back.
So I have to ask, I mean at this point, you're…you're in literally a cutting-edge field, right? Are you concerned that you're not going to be able to continue with the research, if you're back in Athens?
No, because every single vacation, even for five days, I would jump on the plane and go back to the United States.
Uh-huh. And this was the plan? You figured you could make it work this way?
I talked to my friends and collaborators. They said, "You're always very welcome." Because now, I was working with the people at Goddard. That's where I used to go. I went to Goddard three times a year, or even more, depending on how much money I had and how much time I had. And summers. I went there the summers. I had no vacation in these years. I didn't want to be cut off. We didn't have texting at that time. I mean, the computer software was in cards, you know? But I did as much as possible, and my Goddard colleagues helped me; they got me there for one sabbatical. I had a huge amount of interaction with Goddard. All that time.
So it was like, it was kind of the best of both worlds. You could go back to Greece, you could give back, and you can still stay current with your research.
That's the idea.
The professor who hired me, did nuclear physics in Fermi lab. He came back to Greece to become professor, and he was hiring people like me, because he wanted to be surrounded with people that had international involvement with education outside Greece. And some education in areas he didn't have. He was actually pretty good in that.
Were you teaching also?
I was teaching, yes. I had--
Did you like teaching?
(laughs) Teaching in Greece is different than teaching in the States, I can tell you that. The first class I taught had about 300 people in there, and basically I used to be, well, imagine me with very short hair with a little tail coming out, with very short, really very short hair, and-- The first time I got in the class, and I moved on the lectern, people didn't even notice me. They didn't think I was the professor, it was not coming across. So I started banging my hand, and I said, "Please quiet." And then they looked at me, and they couldn't believe it. I was not their age, but close.
And then, they took out the newspapers, they started reading newspapers. Some of them were playing backgammon, you know. This is Greece in the 80’s right? And so I got pissed and I said, "Okay, whoever wants to read newspaper, please go out. Whoever wants to play backgammon, please go out. Whoever wants to listen, please stay here. Nobody has to attend. There is no obligatory attendance. There are other places to sit, go outside and let me teach." Or something like that.
Now, your position on the faculty, were you, like, the astrophysicist? Was that the idea? What was your appointment?
No, I don't think he was going for astrophysics, but he was going for people who were making the department better. The department had physicists and no astrophysicists when I joined it. In 1981 they changed the education system. And they made it identical to the American one. So you had the lecturers, the assistant professors, the associate professors, and the full professors. And they re-organized and I became an Lecturer. Non-tenured. At the same time, there was a movement to actually develop an independent astrophysics section, because there were a lot of astrophysicists, and it was important. Not all agreed to split… but in the end it happened after a vote. I joined the astrosection and I did get the tenure, and then a year later, I got the promotion to assistant professor as well.
But are you thinking at this time, with the tenure, that you're gonna make a life for yourself in Greece? Or in the back of your head, are you think, "I'm getting to Goddard one way or another, it's just a matter of time."? So probably (
Yeah, I'm thinking--) you're not so concerned about tenure in Athens, if your ultimate goal is to end up at Goddard, right?
Yeah, but it doesn't hurt to have tenure.
No of course. But you're thinking, you're, you're, you're never settling on the idea that you're a lifer at the university. That's, that's just where you're going to be?
So I never settled for the idea that this would be for the next part of my life or until I'm dead.
I'm following my path, and I'm very open in making turns whenever I need to. If there are obstacles.
Now, do you have a standing job offer at Goddard? I mean, how much-- how certain are you that this, that you're going to land safely at Goddard when you have this plan in place?
I was at Goddard at the time. Sorry, I skipped some time because of course, I got hired 1982, and we're talking 1993.
So I've been at Goddard for a sabbatical in 1985-87, and three years later, I get a call from Gerald Fishman, who is the PI of BATSE on the Compton Gamma Ray Observatory, that's about to launch in 1991. In April 5, 1991. He calls me in the beginning of the ’90 fall, telling me, "Would you like to come and work with me?" Because he wanted someone who had worked on gamma ray bursts. And that's why he said, "I couldn't find a lot of people that would be willing to move and have done gamma ray bursts, so if you're willing, I would love to have you." So I said, "Sure." So I take ano--
So this is just a, this is just as a sabbatical. We're not talking about a permanent position.
That was a second sabbatical.
So basically, I go to Marshall at that time as a USRA employee, because I am a contractor.
So you're in Huntsville at this point?
I am in Huntsville, yes. I am in Huntsville as of January '91. And Gerry picks me up with Nancy, his wife. They're my best friends. I know them since then. We've been through a lot together, and we're always in contact. I go back and visit them. Amazing people. Nancy is just as close as my sister. So I get in Huntsville in a storm, I take a taxi, I go to the hotel, I get there around nine, and I have a call from Gerry Fishman, and I call them back and he was very worried because I didn't call him when I landed. I didn't have a cell phone, so he could only call me at the hotel. At any rate, there was a flight delay, and he did not know whether I made the plane, from New York. I couldn't interact with them. So he didn't know when to pick me up, whether I made the connecting flight or not. And the next day together with his wife come and pick me up, and they take me all over Huntsville, they find me an apartment, perfect.
After the sabbatical year, I went back, just to renew my position, and then I asked for a leave of absence. So I went there for a second year. By that time, I was a tenured assistant professor. Then the third year, when I asked for another leave of absence, without pay anyway, they said either retire or resign or come back. They were not going to give me any more leave. So I--
Did you find this reasonable? Given how much time away you were spending?
Yeah, I did. I mean, they were expecting it, and I was planning on it. That was difficult, though, because I had met my future husband in the meantime, who was Dutch, and it was much easier for us to see each other between Greece and the Netherlands.
Where did you meet him?
In a meeting. And so--
And he lived in the Netherlands?
Yes. He was Dutch.
The meeting was in Gree-- But he, he lived in the Netherlands?
Yes, he lived in Amsterdam. He was a professor at the University of Amsterdam in astrophysics. A very well-known scientist, as a matter of fact. So basically, there was a time I was in a quandary. Shall I go back so we can meet more often? Obviously, we couldn't meet as often as we did before, because he could take the plane and in three hours he was in Greece. And now he would need 15 hours travel to meet me for a week or so. So, I asked him, "What do you think? Should I stay? Should I drop out? Should I just go in a year, two year contract, or shall I just stay permanently?" And, what I really cared for was, how is this relationship going to develop in long distance?
And he's not going anywhere? He's staying in the Netherlands, this is where he is?
At that time, yes. (laughs) I mean, he is where he is, he's a full professor. He is very well-known, he has an established life. His whole life is there. He traveled in general, but moving to another country without a job, as a matter of fact, that would not be a good idea. And so he said, "This is your decision. Leave me out of that." And he knew, he was wise, a very wise person. He actually said, "If you like it, you love me. If you don't like it, you blame me. So I don't want to influence the decision." And he was absolutely correct, I've used the same words to my students, to everybody who asks me for advice, that is life-changing advice. It's your decision. Don't--
What language, what language were you speaking in with him? English?
English. So we both tried to learn each other languages later, but we didn't last very long, because when we got stuck, we immediately switched over to English, so it didn't work. Especially for me, because I knew German. Dutch and German are very similar, and I always got confused.
So I spent a couple of days agonizing and realized that it's going to be more difficult, but I really wanted to stay in the United States. I really wanted to work on this experiment.
And not just United States, you really wanted to be in Huntsville?
I wanted to be working with data from BATSE.
And Huntsville was the place to do it?
Yes, because Gerry was the Principal Investigator of this experiment. He was running the whole team. And I was given a lot of responsibilities, because I knew the field and I knew a lot on gamma ray bursts -- More than anybody else at that time. Now everybody knows about it, of course, but at that time, I could look at the event as it came down, and I could say, "This is a solar flare," more or less. "This is a gamma ray burst." The first year, I even knew the dates of the gamma ray bursts. Because they are named by year, month, day, like GRB 900513. And I could tell which one it was by the looks of it. At the time there were about 100 of them. When we started getting to several hundreds, I couldn't remember them anymore.
So, to reconnect with the timeline, I quit, I retired from Greece, and stayed in Huntsville. And we got married in '93, and Gerry said, "You know what? Jan--" Jan van Paradijs was his name. "Jan is a fantastic professor, maybe he can get a part time job at the University of Alabama in Huntsville, and that would be great for our group, because he would spend half of the year with us and work on gamma ray bursts. He was a fantastic scientist. One of the most brilliant scientists I worked with. And I'm not saying that because he was my husband, but he was an international presence.
Maybe that's why you married him? (laughs)
Well, no, I married him because I loved him. (both laugh) I got to realize how important he was in my life after we got married. We lived together after that, instead of meeting for a week or every two, three months. They opened a position at the University and they hired him so he was part time in Huntsville and part time in the Netherlands. So, I was going in the summer to the Netherlands for three months, it was quite a traveling period, even the KLM, the flight attendants, knew him. I knew the ones in Huntsville, he knew the ones in Amsterdam. He was coming once a month, more or less, at most every month and a half. And then I was going there. That was tough.
So where are we?
Your husband has the joint appointment, and you're, and you're going back to Netherlands in the summers.
Yes, that's right. No, I meant where are we in the science part? (laughs) Because this is the life part. After CGRO is launched successfully the data started coming down, gamma ray bursts came in a deluge. I mean, they just came one a day, one, two a day sometimes. Rarely three, but basically one a day. We got data up the kazoo. And basically, this was the hardest-working time that I can remember. I spent hours in the operations room, as we called it. In other words, where the data were coming down. I spent hours and days interacting internationally with colleagues, because I was coordinating what we called the follow-up observations. The observations that were looking for counterparts. Other wavelengths. We had no idea what we were looking for, but we had some idea there must be some counterpart. There must be emission in other wavelengths. The situation got clearer when BeppoSAX was launched, which was an Italian-Dutch mission, and one of its instruments, the wide-field camera, had the capability of localizing X-rays. I mean, imaging in X-rays. And there was also a gamma ray burst detector on the same spacecraft. So it was the first mission that had the simultaneous, more or less, several seconds' difference, capability of imaging the gamma ray burst location direction. I'm talking about direction because that's all you could get. So we found and published the first small error box of a GRB. Actually the paper is led by my husband, then his two students who did the observation, and myself, and then the whole group. And so the gamma ray bursts took off.
We first got a relatively large error box with the wide-field camera and narrowed the box with the gamma ray burst detector, and then the optical telescopes looked within the smaller error box and identified a source. Then a day later, we looked again, both in X-rays and in optical, and the source brightness diminished. It faded. So we knew it was a transient, and it was exactly where it should be. We located that, but we couldn't find a host. In other words, a galaxy that this object was coming from. We couldn't see the parent, or host galaxy. All we knew was, we found the first counterpart. And we believed it was extragalactic, but we were not sure. In May-- that was in February. In May, the second GRB was followed up, and in that time, the optical observations had spectra. So we could see the lines in the spectra. We could calculate the redshift or the velocity with which the actual galaxy was receding from us, and from that its distance.
And we found out that it was sitting in a galaxy far, far away. And immediately, the question, are they local or are they cosmological, was firmly answered - these were extragalactic. In fact, that kind of was the second great debate. I don't know if you're familiar with the first great debate between Shapley and Curtis? That was in the early 1900’s.
It was on the galaxy nature - are the galaxies little nebulae in the sky, or are their own star ecosystem? And Curtis said, "Yes, they're all like our own galaxy. They're not nebulae." And Shapley was saying, "No, there are no other galaxies there”. And this was the first great debate, and then a colleague organized the second great debate. At least that’s what we called it… Are gamma ray bursts, galactic or extragalactic, that was the debated question. Paczy?ski was defending that they are extragalactic, and Lamb was claiming that they were Galactic. The audience all had the two or three different buttons, galactic, extragalactic and maybe an I don’t know button – not sure.
So after the debate, we voted with the buttons. The Galactic and the extragalactic was about 50/50. It was almost equally distributed, I mean there was no prevalence of one side. Soon after that time we published the distribution of the GRBs in the sky, and we could explain why their distribution pointed to their extragalactic nature, but with the May event we nailed it. Actually Metzger, Kulkarni et al. nailed it. Because they were the ones who published that. And so we realized we were looking at an extremely energetic phenomenon. We also realized what would be the best way of finding counterparts, which actually was immediately go and pivot to the area where this is coming from, and you will find the counterpart. We observed them in infrared and radio, in X-rays, other than gamma rays, and optical. And millimeter waves in several events. So, we realized that the gamma ray burst phenomenon, which was an unknown quantity in our lives, was associated and related with a huge amount of physics, astronomy, and our lives itself. You could study galaxies with gamma ray bursts, you could study compact objects with gamma ray bursts. You could study radiation mechanisms with gamma ray bursts, or you could start from the beginning, what creates them? I developed the T90 distribution of gamma ray bursts, which is basically a duration, since we can't do very much with the light curves, the best thing we can do to use them is to calculate their duration. And so I plotted the distribution of durations and they split into two main peaks. Some colleagues have identified a third minor peak. The main categories are the short and the long gamma ray bursts. And then the theorists came back and said, "Okay, we can explain the short gamma ray bursts and we can explain the long gamma ray bursts with two different models." And for the long gamma ray bursts, it was Stan Woosley who developed the collapsar model. Stop me when we need to finish.
No, no, go ahead.
Okay, so that model involved a big star, which collapsed onto its core expelling much of its mass. And through the collapse, the central part becomes a black hole, or maybe a neutron star. The central part of the star collapses much faster than the outer layers, or whatever is left from the outer layers. Then these outer layers are falling back into the compact object, and then bounce back in a jet. In the process there is a huge amount of energy coming out, and that is what you see as a gamma ray burst. The jet is coming out of the source, pushing away the material that was around the original star from its earlier wind, and as the ejecta push this material, they create a shock front. As the jet moves out it expands and the ejecta slow down and cool. So the original radiation, which is the most energetic part, is in gamma rays, but as they cool down, they go into longer wavelengths and lower energies, so you go into the X-rays and the optical, infrared and radio, if you are lucky to see all that.
Now, the, the things that you're discovering at this point, how, intellectually, how much is this connecting back to your initial dissertation research? In other words, the things that you're thinking about during your dissertation in terms of theory, is this one intellectual trajectory where now you are confirming some of the things that used to be theory? Or do you feel like at this point, you're operating in a, in a totally new world?
In a totally new world. Before, there were, I don't know how many models on gamma ray burst origin. Some people thought there were little green men.
Signaling to us. Some people thought they were asteroids falling in a neutron star. Some people thought they were Galactic, or coming from within the solar system, even. So it was a puzzle. Okay? We did not know. We had about 50 models. In fact, there was a paper about how many models existed at that time in gamma ray bursts. There were many. 50 or something, and some of them were completely off the wall, but never mind. So now we have two prevailing models. For the long gamma ray bursts, predominantly is the collapser model. And then the short gamma ray bursts, had been associated with the merger of two compact objects. Most likely two neutron stars. However, as this particular phenomenon would require the emission of gravitational waves as well, we thought that we could tie it to the actual short gamma ray burst origin if we observed a gamma ray burst and a gravitational wave trigger at the same time. Which, as you know, happened in '17. And when the actual association of the gravitational wave emission from the merging compact object was tied with the short gamma ray burst, it confirmed the origin of the short gamma ray bursts as merging compact objects. So you have to realize, 50 years passed from '67 when this phenomenon was first detected, until 2017, when we discovered what the nature of these short gamma ray bursts was. It took a long time. In fact, I edited a book on gamma ray bursts and we were pretty on top of what we had at that time. A lot of great colleagues wrote chapters in that book. I was very happy. Maybe I need to re-issue it with an update, but that's a different story.
So basically, we got to the point from phenomenology, which really was what we were doing at the beginning, to understanding the physics of the phenomenon. And we modeled it. We found out what kind of environments these explosions live in. We found out their energetics. We found out their frequency. What we do not understand is what the central engine is, as we call it. In other words, what powers, eventually, the gamma ray burst? We're still observing the disease, but we don't know the origin of it, so to speak. We understand a lot but the question of the central engine is still open. Thank god, because that's work insurance, kind of. So this is what we're working on right now. And we're hoping to be able to form a big collaboration to study that phenomenon eventually.
There are several networks, collaborative networks, that have been formed, international and local, to go hunt for gamma ray burst counterparts. We have right now the Fermi Observatory with the gamma ray burst monitor, and next we're going to have SVOM and also the Chinese are coming up with missions to observe gamma ray bursts. They have already launched the first X-ray satellite in China. And they're all going to go for the next round of gravitational wave detectors and look for counterparts - they're all preparing themselves. And we have Swift obviously, which is the train, the little train that could. I mean, it started as a gamma ray burst detection mission, and it has detected practically everything in astrophysics. And I hope it will stick around until the next US gamma ray burst mission. We’ve done a lot of discoveries that started with Swift GRBs. We found out counterparts, optical counterparts of short gamma ray bursts. We found hosts of short gamma ray bursts. We found what the difference between the hosts of the short and the long gamma ray bursts are. We understand the energetics of gamma ray bursts. We're still discovering things, but the difference is it's not coming like a watershed. It's just coming slowly, every development, every new window we open--
So this real breakthrough was in, what year was this, when you have this...You're describing this real breakthrough. This is, this is in Huntsville, this is like 1993, 1994?
1991 to 1999. So, '93 I wrote the paper with the two different populations based on durations. That is now a classic.
And your time at the Institute for Space Physics, this is, you're continuing the work throughout this time? When you're at the Institute for Space Physics.
Institute for Space Physics?
The depu-- you were deputy director from '95 to 2000.
Oh, you mean ISPAE - Institute for Space Physics, Astronomy and Education.
You're talking about Huntsville now.
Yes. I was until 2000, then I was an IPA with NASA.
Well, you were, you were the, the IPA with Marshall from 2000, from 2000 to 2004.
Okay. Before then, I was a contractor with USRA.
We had a cooperative agreement between NASA, USRA, and the University of Alabama in Huntsville, and that cooperative agreement was ISPAE.
Uh-huh. But your, your employment was with USRA?
The agreement director was from the University of Alabama in Huntsville. I was the deputy director because USRA also had a contract with Marshall. So I was leading the USRA astrophysics team in Marshall, which was at that time, about 10 people. And then I got to be an IPA, you know what an IPA is?
Okay. No, I'm sorry, I'm asking because I don't know if you do.
No, of course. Of course.
Yeah. And in 2002, I believe, I got my citizenship. And then I got hired immediately as a G-15-10, at the very top of the government grade box.
If they could give you higher, they would have. (laughs) That's what a GS-15-10 means. (both laugh)
Yeah. I guess I was professor level at that time. So I got hired in 2004 as a civil servant. At 2013, I became a senior technologist, ST. The government has the Senior Executive Service, SES, who are doing mostly administration. The STs, and the SLs (Senior Leadership) are mostly an honorary title. I think they discontinued the SLs, and now they only have SES and STs. I was an ST when I left NASA.
And you were, and you moved to headquarters in 2005? To Washington?
Yes, for a year to do a leadership development program.
Yeah, now I'm interested in that. What was the idea there? Did you have, I mean what were your career goals at this point where you would want to engage in a leadership development program?
I was thinking that, ok, I'll tell you right now, I just want to say that there is a whole part of my life that I haven't discussed. The magnetar story. And that story.
Oh right, yeah.
So we'll get there, but at 2005, I started thinking that I need to do something--
It's okay. (laughs)
Basically, I was thinking, "Okay, I am at the stage of my life that I can do things like building a team" - as much as I can, because I did not have the-- when you are a federal civil servant, you have limitations. You have privileges, but you have limitations also. You have to do whatever the government deals to you, right?
So in order to be able to do things to develop a team, to develop a group, I needed to be in a higher level. So I decided to get into this leadership development course, to understand how NASA works and what it takes to get into the leadership position. And it was a fantastic course. 25 people together in that class. We had a huge amount of fun together. We did all the classes, we got a lot of experience. I learned a lot. It was worth every minute. And at the same time, I worked. We had to do three projects. Two six-month long projects and one year-long project. The last was for the whole group, 25 of us. And then individually two 6-month projects. So I did one of my projects with the Astrophysics division of the space mission directorate, SMD. And the other project, I did it with another Headquarters division. I know what the project was, but I forget what the department was called, because it doesn't exist anymore. They changed it, they restructured. So I did both projects, I learned a lot about NASA, about the way the federal government works, about what I want and what I don't want. And then I went back to Marshall. And basically, I realized that I didn't have a lot of options.
In the meantime, my career was still going on, was still moving, and I always got involved in way too many dances, every time. And so right now, it is 2013 and I am an Academy member, which immediately makes me, I think, maybe the only one out of two in Alabama. I'm not sure how many there were. And then I'm getting inducted in other Academies as well. And so basically, I started getting offers. I got an offer, a very good offer from the University of Alabama in Huntsville (UAH). And an offer to move parallel in rank to Goddard. Which was very nice, because I always wanted to work in Washington at Goddard. Okay? So, but they didn't come with the same budget as UAH and I couldn’t build a team. While UAH came with a big team and a big budget.
They gave you everything you wanted.
At Alabama, yeah.
And it was a very attractive option, and I was grateful for that, but I wasn't sure about this. In fact, I was talking to a colleague in George Washington University saying, "I can't believe this, I'm getting a fantastic offer in Alabama, and another fantastic offer by NASA, but not as fantastic as far as the UAH one, but the fact is that it's in DC and I'd love to be in DC and have the offer I have from Alabama." Because eventually, I’ll retire for good, and since my husband passed in 1999, I haven't remarried. So basically, I wasn't planning to stay forever in Huntsville, although I could have, because I have wonderful friends, but they have their own family. Not having a job to do and being a retiree, I would have been very bored, because the opportunities are not as big as here in DC, right?
Right, sure, sure.
So I was planning to eventually retire in Washington, because I liked it very much. And so I was talking to my colleague about that, and he said, "Wait just a second, I'll talk to my chair." So about a couple of hours later, the chair calls me back and says, "Would you want to move to George Washington University and bring along more or less the offer that you have from Huntsville?" I told the chair what offer I had from Huntsville, and we negotiated, we matched as close as possible, and it was very attractive to me. So the moment you start negotiating, if you're a civil servant, at the ST level, you have to go to your supervisor and say, "I am entertaining the idea and am in the process of interviewing for another job." They need to know. In fact, I think everybody should tell their supervisor that they're doing this if they're in good terms. I don't think he believed me. I don't think he believed I was going to leave that position, which was the glass ceiling for me, right? There was nothing above this, to be honest with you.
There was nothing above this in terms of your field, or in terms of being a woman? What do you mean by glass ceiling here?
Sorry, maybe I used the wrong term. As far as promotions are concerned.
Right. Meaning that beyond this, you're just gonna enter into bureaucracy?
There was nothing else.
Not even that. And as an ST, the only thing I could change was my salary up to a certain limit of the government. But ST was the end of that path.
I would have to go in a different path, to go in an administrative position, or anything else. I mean, I had followed the track up to the end, basically. Promotion-wise.
So maybe this is a good point, as you're making this decision to go back to this other issue that you've wanted to, to discuss. It's this other issue in your, in your life.
The magnetars, you mean?
That's right. Right.
How much time do you have?
(laughs) We have about...about a half hour. We can do about a half hour.
Sure, well I mean, you know, up to this point, I mean, be-- after we talk about that, we're, we're talking about GW to the present, so that's more than enough time, I think.
Yes. And so, so the first sabbatical I did at Goddard was not for gamma-ray bursts, believe it or not, because actually, I was in the solar group. And basically what happened is, they had a detector on the Solar Maximal Mission that could detect solar flares, and transient phenomena in general, and in the mix, there were gamma-ray bursts as well. So I was there to work on solar flares, for two years, during the sabbatical, and I decided to work on gamma-ray bursts as well, because obviously, gamma-ray bursts were my expertise, and the leader, Brian Dennis, the PI had no problem with that. In the end I wrote a paper on solar flares and papers on gamma-ray bursts, and I had to develop the software to detect the transients, basically all across the observing period. And pick up the transient events that came up, so you detect photons, and you check if the arrival rate is constant with some variations, and all of a sudden, there is a transient that jumps up. And depending on the profile of this transient, the duration, the structure, and the spectrum - the energy distribution of the photons, you can determine if it's a gamma-ray burst or a solar flare or something else. So I developed this program, and I was looking for transient phenomena. On my spare time, which you can imagine was after five o'clock until eight o'clock, but at that time, I was living about ten minutes' drive from Goddard, so I didn't have to--
So this is unofficial work? This is really like a side project for you?
Yes, yes. Because I was hired for the solar part.
And as a civil servant, there wasn't really room for you to--
Oh, I wasn't a civil servant then. I was a visitor from Greece on a sabbatical.
Oh, right. Right, right.
So basically, I asked Brian, "Can I do whatever else I want to do?" And he said, "Sure, I mean you can work whenever you want." I was doing what I asked to do, and I was doing the other stuff on my own. So an interesting factoid here is that the data were coming in tapes then.
Okay? These were big tapes. So I had four monitors, four computers, and four tape machines, tape readers. I was going to the building where the storage place of these tapes was. I was putting as many tapes as I could in every hand, and I was moving with the tapes back to the lab where I was working. And then I was mounting all four every time for a batch of four. And I had four screens, my program stopped and beeped every time they detected a transient, so I was going from one screen to the other to see if this is a transient to flag as a gamma ray burst or just noise. So I was flagging all that stuff, writing, typing. For hours, I was running around these 4 machines, and then if the tapes were done, I was mounting more tapes. I mean, weekends as well. I mean, this was crazy, but I think that was one of the most productive periods, because this is where I found the magnetar bursts. So basically the gamma-ray bursts, let me say that, are catastrophic phenomena. In other words, when two neutron stars merge, the outcome is one object. It's either a neutron star or a black hole, most likely a black hole, and that means that this object, the final object, cannot merge and produce another explosion, another gamma-ray burst. The outcome of a collapser is also a compact star. It's not a binary system. So basically, the opportunity to explode and release the same kind of energy is gone. So you do not expect to see a gamma-ray burst from the same position more than once. Because it's the death knell of a star, right? You don't expect this to repeat. And all of a sudden, we get a message from Kevin Hurley in Berkeley, that he has identified a series of X-ray bursts, not really gamma-ray bursts, but lower-energy bursts. Must shorter than the general gamma-ray bursts. These seemed to come from the same sector of the sky, the same general part of the sky.
What year is this, that this call is coming in? Late 80s?
80s, '85, I think.
Oh okay, earlier. Earlier.
Something like that.
And so we knew that one of these X-ray bursts, the 1979 March 5th event, was followed from the same direction of the sky by several smaller events. There was also some repeated emission that the Russians had found, from the Sagittarius area. And basically, that was also a repeater. So we knew that there were some events that were repeating, but we did not know why. And I couldn't believe they were gamma-ray bursts. People thought they were just gamma-ray bursts because they were detected with gamma-ray burst instruments. But they were different in many ways. Duration-wise, spectrum-wise, and repetition, which was not expected from gamma-ray bursts.
And this was apparent to you immediately, or it took time to figure this out?
Initially, I was not aware of that. I got the message, as several astronomers did that worked on high-energy astrophysics transients, from Kevin Hurley saying, "Look at your data--" He sent it to me because I was, he knew I was looking at the Solar Maximum Mission (SMM) data. "--to see if you have seen events at the time I see them." Because if his mission saw it, SMM should have seen it as well, if they were looking at the same part of the sky. He gave me dates, so I went and looked at the tapes of these dates. And lo and behold, I found the events. At least two or three events that were simultaneous with his events. Which immediately confirmed that this was an event of physical nature and not an instrumental event. Because--
What does that mean, physical or instrumental?
It means, that the instrument did not produce noise that could qualify as an event. Because I saw it too.
So it really happened. That's the idea? It really happened.
That's right. So he saw it, I saw it, it's from nature. It's not from our detectors. Okay? Because he wanted to confirm that, and then other missions also confirmed. So we published a series of papers, three papers, with all the groups together. So one was headed by Los Alamos by Laros et al. the other one was head by Atteia et al from France. And the other one was headed by me, at Goddard. So we all published the detections. And we established that this was a real phenomenon, and not noise. And then we met in Toulouse, I think in '86, and we decided to call this a "soft gamma repeater." Because it wasn't very hard gamma-rays. Quite honestly, we debated also to call it a "hard X-ray repeater," but if you initialize soft gamma repeater, you call it SGR. And that's easy to say. Now, if you initialize hard X-ray repeater, you have to call it HXR, and it's much harder to say. I don't know if that makes sense to you, but--
HXR. Sure. (laughs)
Yeah, but SGR, I mean, it's much easier. Anyway, so we called it soft gamma repeater. And we stuck with it because that's all we knew.
So basically, the question was, are gamma-ray bursts a different phenomenon? If they are a different phenomenon, which they have to be because they do not repeat, what causes the repeaters? And so this is the second time the same question came up. But it was now dual in nature, were they the same as gamma-ray bursts, and if they are not, what are they? There were a lot of people who claimed that this was the same as gamma-ray bursts. I was very adamant, because I had seen hundreds by that time, that this was actually a different phenomenon. And the person who published that, the Russian Eugene Mazets, was the PI on the Russian instrument that detected the repeaters - they were detected with the Veneras and the Prognoz missions. Mazets said, actually, in the paper where he published that, "It is very possible that they constitute a different phenomenon."
So basically, he said that it is very probable that these are a different phenomenon than gamma-ray bursts. We found more gamma repeaters, soft gamma repeaters, in the 90s, when BATSE was up. But we did not have counterparts for soft gamma repeaters yet. We did not know where these were, right? One of them, from the March 5th event, was coming from the large Magellanic cloud, which is a satellite galaxy to our galaxy. So it was not in our galaxy. The other two sources known at the time, we did not know where they were coming from. We knew a general direction, but we did not know whether they were part of our galaxy, or were they extragalactic as well? We didn't know. So we kept looking for these events, and they are very characteristic. The bursts they emit are very short, 100 milliseconds, 150 milliseconds of the average. And very soft. They're not gamma-ray photons, they are hard X-ray photons. They are of much lesser energy. And sometimes the bursts come in bunches, and then they stop, and the source becomes inactive. Or sometimes they just emit one or two bursts and that's it. So that was the second mystery I was supposed to address, to solve. I put a lot of effort on that.
One of the Japanese satellites, ASCA, was active at that time and it could actually find the counterpart in the X-rays. And all we needed was an active source, because after they emit a series of bursts, they go to sleep. And they become totally inactive for quite a long time. Some of them, they never become active again. But some of them take months or years to become active. Unpredictably. Completely. Eventually we detected magnetar bursts with BATSE. We called them SGR bursts then. We couldn't locate them very well, we had big error boxes, in the direction of the Galactic plane, so we thought they might be Galactic plane objects, but we didn't know for sure. And there are a lot of sources in the Galactic plane, so you needed a very accurate location in order to see which is the source that's emitting the magnetar bursts. We didn't have that capability for localization, until one day, when BATSE triggered on another soft gamma repeater burst. I sent the information about the general location to the ASCA team, to Japan, because I was the BATSE team link with all the international networks. And a colleague who was from the States visiting Japan, put the satellite on it, and they found a counterpart. And he located it in the Galactic plane, so finally we knew they were Galactic of origin.
The question now was what were they? The actual huge event of the March 5th had this big initial spike, and then it had a tail with modulation. Now, the modulation was periodic. About eight seconds, but there were only about five or six cycles, and then it died off. The only thing that can create a modulation like that is a neutron star. So there was already evidence that the emitter was a neutron star, and you were seeing the actual spin period of the star. How fast it rotates. But we didn't have other evidence for that. And so with ASCA, we located the source pretty accurately. Because we had seen this tail with the eight second periodicity, when the Rossi X-ray Timing Explorer was about to launch I wrote a proposal to observe that source and other magnetar sources whenever they become active. The Rossi X-ray Timing Explorer had an instrument that actually was a photon bucket. It was collecting a lot of photons. It didn't have a good locational capability, but it had a huge capacity to collect photons.
So, putting it on the sky at the moment when a soft gamma repeater became active, would allow me to collect a lot of photons and then do timing analysis on these photons to see if they have a period. So I wrote the proposal, and it was accepted. An old source became active. We collected information, we did the timing, and we found a spin period. And then we took the old ASCA data, and did the same analysis, now we knew what the period was. Once you have a value you can take that period and search in other data from the same period, and see if it showed in these data. So we did that. We detected it and we also found out that there was a slight difference in the period, before the last observed one. Which meant that we could measure how fast the source slowed down.
Okay? So there is a source that's rotating, it's losing energy. The more it's losing energy, the slower it becomes, the period becomes longer. Do you follow me?
Okay. That is what we call "spin-down." Depending on how fast the spin-down is, there is a formula that produces the magnetic field from the period and the period spin-down. So you can fit in the formula how fast the source rotates, and how fast it slows down. And then you come up with the magnetic field. We did that, and the magnetic field that came out from this particular source was humongous. It was huge and it fell into the category of magnetar, that Duncan and Thompson had published in '85, prior to the discovery. They said, "There is a very good chance that magnetars are what powers gamma-ray bursts." Basically, they developed the whole magnetar concept and said it would explain gamma-ray bursts, and they called such objects magnetars.
And this proved their theory?
Yes. It proved that there were magnetars in nature, and basically that's what we published in Nature. The paper took seven days. From the moment we wrote it. We wrote it in a week, and it was approved in a week.
And in fact, one of the referees was Bohdan Paczynski and he just wrote, "Publish." (laughs) That's all he wrote, practically. Or something of that effect. The report was very short. So we published that, and then we started finding more soft gamma repeaters slowly. So that was the moment where Gerry Fishman agreed that this is a different phenomenon, and we were all very happy, I mean I'm joking now, but he also became a convert.
But then I started working a lot on magnetars, and we found more. I mean we have done a lot of work. With the people I work with on magnetars, we've done a lot of observations in different wavelengths. We looked for counterparts, we looked for associations with massive star clusters, and there is some evidence that a few magnetars are close to such clusters. Or that there were possibly ejected during the formation of the second compact object. We believe that the emission that we're looking at is basically the crust quake of a neutron star releasing energy that we actually see as a burst. But there are several theories now. The bottom line is that we started with an esoteric phenomenon that nobody believed and we are now a community which believes that there is magnetars all the way. Now, magnetars are actually invoked for the gamma-ray burst as an intermediate stage, I should say, between the collapse and the final creation of the compact object. There might be a very heavy neutron star formed as a magnetar and then a black hole. We don't know. There is magnetars in many places these days. So--
So you were really onto something in the mid-80s, essentially. It's still--
It's still a collective effort.
My most important contribution was the idea to have the proposal for RXTE to observe them and basically look for the period and the p-dot. Sorry, the spin-down. I called Thompson and Duncan and they were jumping up and down. I said, "We found a spin-down that confirms the magnetic field is huge." After that, it was grind work – look for more, analyze more data… take more observations, use as many missions as possible…
Well, I know our time is rapidly coming to a close, so I wanted to ask you, I, I have a few sort of retrospective and introspective questions to ask. But my only question about your appointment at GW is what the Astronomy Physics Statistics Institute of Science's, APSIS, I, I assume you call it APSIS, or what's the shorthand with this?
APSIS, but this is an institute I formed.
I'm a professor in the physics department.
Right. My question is, my question is, when you, when you got the appointment, was, were they competitive with Alabama on the basis that you would be able to create this institute?
No, the institute I created after, a couple years—
After. So how was GW so competitive with Alabama? Given all that Alabama was, was, was offering you, what was, what was the draw to come to GW, then?
DC. It was about DC.
Just DC, I wanted to retire in DC.
That's what I mentioned earlier. They were competitive. They offered more or less what I asked. And now we have one assistant and one associate professor. And another opening hopefully coming up this year. I have three graduate students, myself. We have about 10 graduate students that want to do a PhD in astrophysics, which is not what used to be before we came. We have a very strong group and basically, excellent people in my opinion, and even better, people I can work with.
So APSIS, what was your motivation in creating APSIS?
I wanted to have an interdisciplinary institute including Math and Statistics department colleagues to do data analyses, because we have a lot of large data sets in astrophysics. We wanted to make sure that we can actually work across the disciplines.
All right, so for my last question, I'd like to ask about, you know, the future. What are things that you're really excited about that can be discovered, you know, in the course of however much longer you remain active in the field, or even beyond? What are the things that you don't know now but that you feel can be known, and that will be really breakthrough discoveries? What, what are those things in your imagination?
So I started a project with Swift, I call it the Deep Galactic Plane Survey, and I have two graduate students right now working on it. Basically, we are looking for transients in the Galactic plane, in the hope of finding more magnetars, more high mass X-ray binaries or transient phenomena that we are not aware of, new transients. And they're working on it, we have actually one paper published and we are working on two or three more. I personally would love to work on the question: are there different flavors of magnetars or are all the same. Indications are that there are different flavors, so I, whenever I find the time, I'll sit down, and I know what I'm going to look for but I mean this is a project that's being developed in my mind in these last years looking at data. I--
Which will tell you what? What are you searching for? What's the big question that you're looking for to answer?
What makes a magnetar. And--
What makes a magnetar.
And if a magnetar is one of a kind phenomenon or if you can create it from different origins. From different mechanisms. And can you have a magnetar that is in a binary system, because so far, all the magnetars we have seen seem to be solitary neutron stars. But I think there might be a possibility, that something could create a magnetar that is not just solitary. It could be in a system. So basically, I want to search. Maybe I'm wrong. Maybe it's just a hunch. We’ll see if I ever get to it.
Sure. Yeah, sure.
Basically, that's what I want to do, I want to look for magnetars and see if I can find different types. It's a long shot, I don't know if this will work out. I also want to see if anybody is going to find out what the central engine of gamma-ray bursts is. I don't know how close we are to that, and then of course, there's the new mystery of the decade, I should say, that is what are fast radio bursts. Because now people claim that they are coming from magnetars. So there is another place where they are supposed to be the culprits. So are fast radio bursts, the repeater ones, magnetars? I don't know. But this is yet another mystery, and if they are magnetars, why don't the magnetars in our galaxy emit them? Because, I forgot to say, there's about 28 magnetars known right now in our Galaxy. Two more are outside our galaxy. So basically, every magnetar we observe is within our galaxy. That's because they are less energetic than gamma ray bursts, so we can't see them in larger distances. But then if the other sources that emit fast radio bursts, which we know are in cosmological distances are magnetars, their X-rays cannot reaching us from these distances. The real question is why don't our own local magnetars emit fast radio bursts? So that's a question here. So there is many questions to work on, I can tell you that. If I get to the point where I'll have some time left for research.
Well, Dr. Kouveliotou, it's been an absolute delight talking with you today. I really appreciate it. Thank you so much.
You're very welcome. Thank you for being interested in all that. And feel free to ask more questions if you have any.