The board of KIF has decided to give this special Lifetime Achievement Award to Associate Professor Emerita Birgitta Nordström for her significant scientific contributions and for being a valuable role model.
The full nomination for the award can be read here
The award will be presented at the KIF annual meeting on October 13th, 2021, where we have invited Birgitta to give a presentation about her research and career.
The following is an interview with Birgitta Nordström by Maren Malling, chairwoman of KIF.
You have had a long and very productive research career. What projects are you working on right now?
I am working on very metal poor stars. Those were the stars that developed first after the Big Bang, and I’m trying to find out what they consist of, how they were created and their ages. One of the projects I do now is a collaboration with Terese Thidemann Hansen, who is a former student of Copenhagen University and now works in the United States. I take great joy in continuing to work with former students and she is not the only one. We are observing some very old and metal poor stars and have discovered that one group of stars is different from most other metal poor stars. We want to find out why. Some stars are known to be binaries, which could mean that there has been mass transfer from one star to the other, but one group of metal poor stars is not like the others. They have more very heavy elements, so-called r-process elements, like europium, silver or gold. We have even found one that contains uranium. So why are they different from other metal poor stars? We are trying to find out if they are also binaries, but for the moment, it doesn’t seem to be the case. It is a very exciting project since it might tell us something important about the early Universe. American observatories have given us a lot of observing time. This is the most interesting project I am working on right now, but Terese does most of the work.
If you look back on the past 20 years, you have done a lot of projects. Which projects are you most proud of?
That must be the project that is most cited. We investigated 14000 stars in the solar neighborhood, meaning the stars around the Sun. What is special about this project is that it is a homogeneous sample. Other people had also investigated the solar neighbourhood, but they took what was available in the literature, and that’s not a good way to get an unbiased sample. We took great care to include all the stars in the volume around the sun. We observed their velocities in the line of sight, which was not an easy thing to do. The velocity perpendicular to the line of sight was known from space missions. So, we made 85.000 observations one by one. We were a team, but in the middle of this project, the first exoplanet, meaning the first planet around another star than the sun, was discovered. So those collaborators quit the project. But I thought that we must finish our project. We had got so much observing time, the project was very interesting and we knew how to do it. At that time, I was a guest Professor in Lund in southern Sweden, and I had a very good postdoc and a PhD student who helped me publish and discuss the data. We finished the project, the three of us, but the other collaborators were of course also essential in the project because they had been part of it from the very beginning. This project is now more or less continued by the Gaia satellite. It is the same type of project the Gaia satellite is doing, only Gaia includes billions of stars, and to much larger distances. Our project was used as a sort of proxy for the solar neighborhood. We found out that many stars that are now close to the sun have not been there for very long, only a few million years. The paper is still cited very much. In fact, our project was one of the most cited at Copenhagen University one year and has been cited thousands of times. I was quite proud that we managed to finish it. My attitude is that if you start something, you must also finish it, if it still makes sense.
How did you get started as a young scientist and what early projects did you work on?
My plan was to become a high school teacher, and I succeeded quite well in my studies of mathematics and physics. My supervisor asked if I wanted to do a summer job, and I thought, why not? I had worked in my parents’ bakeries every year since I was 14 years old, and I wanted to do something different. So, I started with a summer project, which was a survey of the Southern Milky Way – not the Northern Milky Way as we know it here, but the Milky Way one can see from the southern hemisphere, which was not well known at that time. There were no instruments in the southern hemisphere that we Europeans could use. This was the time before the European Southern Observatory (ESO), when the European countries got together and built telescopes in Chile.
I got observations from South Africa from Bloemfontein Observatory. The observations were made with a so-called objective prism spectrograph and were on glass plates. I worked very diligently to find out what those stars were, their positions and how different they were, and I found a number of young new stars that nobody knew about.
An interesting thing happened just recently when I got several emails from astronomers all over the world. One American astronomer said that he had now finished my project. I wondered what project he was referring to. It turned out to be my PhD thesis. I had thought that it was forgotten by now. He had done observations of the exact same stars, and with more advanced instruments that are available today, and he was able to find out more about those stars. For me it was a big surprise that my PhD, which is 50 years old, was still being used! This was possible because in Europe, we started a journal about 50 years ago, and this was one of the first papers published in that journal. We made all the observations available to the whole world. And in that way, we were very early to start with what we now call Open Access for data. I have met colleagues who have said about their own projects: “The observations are mine, why would you make them available to others?” But I think I won, because now they are being used and developed further with new findings. For me it is really interesting that my old work is not forgotten. It is still there and being used.
What was it like when you did your PhD?
I worked and studied at Stockholm University Observatory, and I had the attic floor together with my supervisor and another student. My supervisor was a very generous person and let me do interesting things, not just things that he wanted to be done, so I worked on things that turned out to be really important. I finished my studies rather quickly, and when I had finished, he recommended that I should not stay in Sweden anymore but go abroad and learn something new. I then applied for a fellowship with the European Space Agency. I went to Geneva and stayed there for a year. After that, my next postdoc year was in Victoria on the West Coast of Canada, There I met my husband-to-be, which was the reason why I moved to Denmark.
How long were you and your husband married?
Almost 50 years. My husband, Johannes Andersen, died last year, and we had worked together all those years on similar projects and often on the same projects. Many say that it is not a good idea to keep working with your partner, but it was in our case, because we did a lot of observations and had to travel a lot. For example, I have been to Chile 35 times and my husband was in Chile 45 times, and we took turns to be together with our three children and it worked out very well. He of course did many other things as well, outside of our science projects, as did I. I was hired for a number of European projects. When for example the Soviet Union stopped having much power over the Eastern European countries, I worked to get those countries included in the Western European science community. The Eastern Countries did not have as many facilities as we had, so the aim was to unite all of Europe in astronomy and to get them into instrumentation. That was very rewarding, and I have many very good friends and collaborators in Eastern and Southeastern Europe.
You mentioned to me earlier that you have worked in 64 different countries. Could you elaborate on that?
Yes, that is correct. I’ve had guest professorships in several countries like Germany, Sweden and USA. I have also worked in the Czech Republic, France and Austria, as well as many other countries for shorter visits for certain projects, including EU projects for collaboration. Right now, I am part of two large EU projects, one about nuclear astrophysics which includes many countries in Europe. It is very rewarding to work on this project, and this is also partly in collaboration with one of my former students.
Let us talk a little bit more about the mentoring of young scientists, as I know you have done a lot of that. What advice do you give them? How do you support them?
I will tell you a couple of stories: Once, I went to a conference in Asia where I did not know the language at all, and unfortunately, I had an accident. A student volunteered to take me to the hospital, and apparently, I was a bit shocked from the accident, so I talked a lot. A week later, I received a long email, where the student wrote that after talking to me, she now knew what she wanted to do with her life. That kind of experience is very rewarding to me.
Another student, a young man, said that I had changed his life as a scientist. He told me that he had thought that astronomy was all about computers and that you could compute everything to find out about the universe. But I had told him that one can go out and observe. I met him some years later in Chile, and he said: “Now I’m at an observatory, and I’m finding out what the Universe looks like!”
The advice I give to students is often “You can do it, but you have to work hard”.
It seems that you are very good at encouraging people and seeing their talents. Do you think it is important to give confidence to people to help them find out about their own abilities?
Yes, I think it is very important to encourage people and tell them that they can do it. I had that experience myself when I was a young student at university. Several near relatives and friends had died within one year, and I was quite depressed, and I thought I could not finish my studies as I had anticipated. I talked with one of my teachers, and he asked how well I had done during my first years at university. He concluded: “You can do it. I will give you a month extra time to finish your reports, and you can do it, you’ve done it before.” I did, and I will never forget that, because he gave me self-confidence, he believed in me.
I know you have supervised both young women and young men. In general, do you think that young female scientists need more encouragement?
Maybe, and I think that probably if they do need more encouragement, it may be easier for them to talk to a woman about problems than to a man. In my experience, they would rather talk to a woman that they feel confident with. I have also had male students who have had problems. Actually, I don’t think I have had a single student who has just given up. It is also very rewarding as a supervisor to let them know that they can do it and see them finish.
You have managed to have a lifelong research career and a family. You have three children and six grandchildren. In KIF, this is something that we often talk about, especially with younger female aspiring scientists. What advice do you give to young female scientists who are wondering if they can manage to have a family and a research career?
Yes, that is very often discussed. The thing is, if your partner does not collaborate or accept your career, it will not work. So, you have to choose your partner with care also from that aspect. As I said before, my husband and I always took turns traveling, and there was always one parent at home. Also, we taught the children when they were very young to help out in the household. I asked one of my daughters about that once, and she said that when she grew up, she thought she had to help out much more than her friends. But then she also said that she really appreciated that when she moved to a student residence. She knew how to do all the practical things. She also has a career now and I can see that she does the same thing with her own children.
When your children were young, did they ever travel with you and your husband for work?
Very seldom, because at observatories it is usually not allowed to bring children. Except a couple of times in Provence in Southern France. There we could have a house for ourselves. We went away for a month, and this was a great experience for the children. We did two weeks of observing and sometimes had the children help out a bit at the beginning of the night. After that, we went hiking in the alps.
What do your adult children do now?
One daughter is a medical doctor. My other daughter is a physicist, and she is working in private industry because it suits her family pattern best. My son is a computer specialist. All three have careers which they like and are doing very well.
Apart from your research projects, you have also been involved in a lot of organizations and served on many committees. How did you choose which to get involved in and what is the importance of that work?
First of all, you don’t choose. You are appointed or asked. For example, in ESO (European Southern Observatory) in the early days, they did not ask women to do the most important committee work, but I took those challenges offered to me anyway and it worked out quite well. As a woman, you have to be very well prepared – no mistakes. You have to be very specific and very knowledgeable. For example, I was the only woman on a very high-level committee at the European Space Agency, and I realized very quickly that I had to be extremely well prepared to be heard. Also, I had no one to ask. During the intermissions, the men would gather and talk amongst themselves. So, I had to be a bit pushy to get my voice heard, but then I could have a lot of influence. So, in my experience, women have to be more well prepared, but then you are listened to.
Do you feel that this kind of work is important to do?
Yes, it is. For example, when it comes to choosing science projects, women are sometimes geared towards projects that some men think are not so prestigious. I know I have influenced the choice of a number of space missions by arguing for the most fundamental projects.
What advice would you give to younger scientists about the balance between research and other types of work such as committee work?
As a young scientist, you should not do too much committee work in the beginning of your career because that does not contribute much to your CV. You should do some to get the experience. That concerns, for example, refereeing papers. If you take on all the papers that you are asked to referee, then you spend too much time on that, and your own projects get pushed in the background. You have to think about your CV, that there is some balance, and for this you might also need some mentoring and help. I know a scientist who has taken on mentoring several students, and she points this out all the time. You need to think about your career, think about what is important for your future. That is why I have taken on more and more committee work as I get older because my CV is not so important for my future anymore. I can also contribute with my long experience.
Some women are asked more often to sit on committees because there are few women to ask. I hear from younger female scientists that it is hard to turn something down when they are the only choice.
Yes, and of course it is your own choice how many things you want to take on, but that is true. When I was a student, women were not considered important in that respect, but now it is important to have at least one woman on every committee, and it is often the same women who are asked, but you have to find your own way.
Maybe we should have more women to choose from and more women on the committees?
Yes, definitely more women to choose from. I looked on our institute website. And I could only find one Emerita, but I found maybe 40 Emeritus. I thought that there must be something wrong with the website, but I was the only woman. It probably means that there have not been very many women to start with. When I started in Denmark almost 50 years ago, I knew only four or five female physicists in total. Those numbers have improved, but they are improving too slowly.
What can we do to improve the numbers?
I have no quick solution to that. One thing that is important is exposure, of role models. If you ask a young person what a scientist looks like, it is very often a caricature of Einstein, but if they understand that scientists can be you and me and your best friend, then I think it makes a difference. I did not know any scientists myself, neither men nor women, so I did not take that aspect into my own considerations – except the best teacher I have ever had was a woman at university. I think role models are very important, and I think KIF is doing a good job in that aspect. I have been involved in several projects where we show women who have done very important work in physics or astrophysics, but very often hardly anybody knows about them. You have to bring out the stories. People may know Marie Curie, but there were many others. Also, it is important how we tell the stories. When Dorothy Hodgkin won the 1964 Nobel Prize in chemistry, the next day, the newspaper said: “Housewife wins Nobel Prize”.
Where did your very early interest in physics come from?
I think it was just curiosity. There was nobody in my family or in my Greater family who had even gone to high school, and nobody to university. So, I think it was curiosity. I did not even know much about stars; except one winter I was skiing in Northern Sweden and there I saw something like a band in the sky. In Swedish, it is called the ‘Winter Street’ – it is a band in the sky that you can only see in the winter, Mælkevejen in Danish. And that impressed me a lot. Why did we not see it in the town where I lived? We moved out into the countryside in the summer, but in Scandinavia you do not see many stars in the summer. Other than that, I was interested in mathematics. I found it very easy at school. To become a high school teacher in mathematics, I needed one more topic, and physics was my choice. To study physics and to become a high school teacher in physics, I also needed some astronomy and I decided to take a full curriculum course. So, my path into physics was not very romantic, it was a little bit practical, and then astronomy caught my interest when I was asked to do a summer job during my Master thesis. But I think it was mostly curiosity: “What is it? How are the stars made? And why are they different?” During my summer job, I realized that they were different not only in size but also in composition and colour. I wanted to find out why.
Any last words of advice you would like to share?
There was one thing I learned very early, and that was that hard work pays. At university, when I was about to give up, I was told: “You can do it, but you have to work for it.” So that is also the advice that I give to students. Don’t give up, but you have to work for it! Good results do not come by themselves, and this applies all through your career. Remember that “one size does not fit all”. What has worked for me might not work for my student. Astronomy has developed so much since I started. Back then, the southern Milky Way was just something that we knew very little about. Of course, now we know a lot more, but there is still much to learn and to do.