“The quality of measurements in Asteroseismology has a factor of a hundred better precision now than ten years ago and that is what makes the whole field emerge”

“With the TESS (Transiting Exoplanet Survey Satellite) mission from NASA we will see a much bigger variety of stars and we will be able to complement the data we have now”

“We really have a lack of young scientists entering science and engineering studies”

“Girls need more encouragement than boys, they should not think too quickly that they cannot do Science”

By Elena Mora (IAC)

Conny Aerts is the Director of the Institute of Astronomy at the University of Leuven (KU Leuven, Belgium), as well as Adjunct Professor and Chair of Asteroseismology at the Radboud Nijmegen University (The Netherlands). Her triumphs do not only concern Astrophysics, but she is also the first woman to be awarded the "Francqui Prize" in the category of Science and Technology since its creation in 1933 (known as the "Belgian Nobel Prize"). In addition, she is a woman committed to scientific outreach (she is Vice-dean Communication and Outreach at the KU Leuven Faculty of Science) and to Gender Equality. If she is not searching for observational clues of the internal structure and evolution of stars through Asteroseismology, she tries to get closer to the youth, especially the girls, to teach them that you can be a woman and a scientist in a society that is not going to make it easy. Recently, this researcher visited the Instituto de Astrofísica de Canarias (IAC) within the framework of a collaboration with the IAC astrophysicist Sergio Simón-Díaz. The aim of the project is to study the variability of massive stars combining photometric data from space satellites and high resolution spectroscopy of ground-based telescopes, fields in which they are experts.

Question: How would you explain what asteroseismology is?

Answer: Asteroseismology is the study of “starquakes”. It is similar to seismology of  the Earth. We use earthquakes to understand the interior of our planet and the physical conditions there. We do that for stars. Stars have “quakes” and they create waves that we can observe with space missions. The quakes lead to very tiny variations on the surface of a star and can study them now because we have good detectors onboard space missions.

Q: That is concerning the exterior but, how can we deduce details of the interior physics of faint and distant stars?

A: These quakes happen inside the star and thus depend on the interior physics, but they also produce tiny little variations in the temperature at the surface of the star. So if you have an excellent intensity instrument you can measure it, but they are so tiny that we cannot do it from the ground because the Earth atmosphere prevents us from detecting them. But if we use space missions that are not disturbed by the atmosphere of the Earth, you can see many more details than before. That is why I call it “the new era in stellar astrophysics” because the measurements’ quality has a factor of a hundred better precision now than ten years ago. That is what makes the whole field emerge.

Q: What kind of details we can unravel this way?

A: While we already know the rotation at the surface of the stars measuring their velocities, we can derive how they do it in their interior. So far, in stellar models it was often assumed that the whole star was rotating in the same way, but now we know from the starquakes that this is not true at all. The rotation in the interior of a star can either be faster or slower than at the surface. And that is what makes a difference in the life of a star.

Q: So this is related with the most recent and most important findings made in this field.

A: Yes, interior rotation is a key new finding and in different kinds of stars,  in different phases of their lives. We cannot watch a star grow old because it takes millions to billions of years. What we do is study different types of stars that belong to an evolutionary sequence and so, for each of them, we try deduce how they rotate because it also changes as they grow older.

Q: What is the future of this research domain?

A: We have worked so far with two main satellites, no longer operational: CoRoT and Kepler. In 2018 NASA will launch a new satellite that can also measure starquakes with high precision. The difference is that the two previous satellites pointed to a very specific area in the sky, but the TESS (Transiting Exoplanet Survey Satellite) mission from NASA will point everywhere in the sky with shorter timings. We will see a much bigger variety of stars and that is good because we can complement the data we have now.

Then ESA will launch the space mission called PLATO (PLAnetary Transits and Oscillations of stars) where we are heavily involved with many groups (also Spanish groups). That will do even better, with higher precision measurements during a long time. First results will come  in only ten years from now so I always say that I am heavily involved in a mission whose data  I want to see before I retire. This is going to be a challenge!

Q: Apart from astrophysicist, you are Vice-Dean of Communication & Outreach at the Faculty of Science. How important is communicating science to the society?

A: For me, the most important reason to do outreach is to trigger curiosity with young people because we really have a lack of young scientists entering science and engineering topics and so companies really have a problem. So it has also an economical reason in that sense because vacancies are really hard to fill. And very often, or girls  tend to think that science is something they cannot do. This is not true. They have this old-fashion view of what science or a scientist is. We try to avoid stereotypical thinking of science. For that reason, Astronomy is optimal because everybody is fascinated by the Universe.

I use Astrophysics as a trigger to communicate about science and technology in general and I do that in lots of schools, for ages from 3 to 18 years old. I am mainly focusing on girls because they need more encouragement and should not think too quickly they cannot do science. Their self-confidence is lower than for the boys and then I just tell them my life story. They know that I have children and I have combined it with a fascinating job, so I hope in the longer term we will get more students in this field.

I also give a lot of public lectures for the general public with hundreds of people that just come and listen, out of interest, because they hear about Astronomy but they know nothing about it. In that sense, I do a lot of activities in outreach myself and I also encourage others to do it.

Q: The report “Female Scientist in figures 2015” (“Científicas en cifras 2015”) regarding the unequal situation of Spanish women in Science, showed that despite of the fact that 50% of PhD students are women in Science, they do not reach higher positions during their careers.

A: Yes, it is a pity, the same figures occur everywhere. It starts 50-50 in most European countries, PhD’s are still 50-50 or maybe 40-60 but usually still quite equal. Then if you go to postdoc, the difficulties start. Of course, that is the time when women have children and for them this impacts much more than for men. At senior levels there is a big drop down to some 10%. This situation has been like this for 20 years and it is really difficult to change it. This has to do with encouragements, with flexibility in organizing a career and stereotypical thinking rather than with the competence of these women. It is the environment that does not encourage them to continue. I am also trying to combine my third topic, gender, with astrophysics and communication to illustrate that it is possible to do it. Let’s hope it changes one day.