Interview: Ana Paulino-Afonso


Ana Paulino-Afonso is currently a PhD student at the Faculty of Sciences at the University of Lisboa (FCUL) in Portugal. She has been interested in astronomy from a young age and enjoyed following events such as eclipses. These interests had been temporarily put aside in high school in favour of a studying socio-economics and going on to study Economics at the Faculty of Economics at the University of Porto. However, this was relatively short-lived and Paulino-Afonso switched to a degree in Physics and Applied Mathematics (with specialisation in Astronomy) after just one year of studying for an Economics degree. She obtained a bachelor’s degree in Astronomy in 2011 from the University of Porto and then continued to study for a PhD in Computational Astrophysics at the University of Évora. Unfortunately, this could not be completed due to illness. Later on, Paulino-Afonso picked up her studies by applying for a new research fellowship and studying for a master’s degree in Physics, (in the branch of Cosmology and Astrophysics) at FCUL. As part of this, she completed an Erasmus internship at the Laboratoire d’Astrophysique de Marseille (LAM) in France in the second semester of the second year.  Paulino-Afonso then became a PhD student at the Institute of Astrophysics and Space Sciences (IA-Lisboa) and FCUL in partnership with Lancaster University.

When starting her bachelor’s degree, Paulino-Afonso was more interested in theoretical physics than astronomy and astrophysics, but then took part in an internship project to improve the quality of the images of Class 0 protostars taken with the Spitzer space telescope, and wanted to study the initial stages of star formation after that. Later, she worked within the Portuguese participation in the data and analysis consortium and early science preparation of the Gaia mission in order to understand whether or not Gaia would see galaxies that contain black holes known as active galactic nuclei (AGNs) and, if so, what the effects are on the astrometry. She simulated how Gaia would observe galaxies and if it would help us to search hints of gravitational waves by looking for “kicked black holes” in early-type galaxies. During her internship at LAM, Paulino-Afonso used spectroscopy from the Visible Multi-Object Spectrograph (VIMOS)/ Very Large Telescope (VLT) combined with Hubble Space Telescope (HST)/Advanced Camera Survey (ACS) images to study the evolution of light in galactic bulges and discs at high redshift (between z~0.8 and z~3). Both projects involve the study of galaxy morphology across cosmic time and she enjoyed doing this so much that she continues to search for more projects that are connected to it.

In her PhD so far, Paulino-Afonso has been studying the morphological evolution of galaxies across time and environment. The first part of the project involved taking a sample of star forming galaxies between redshifts ~0 and ~2 to identify how biases in morphological classification by humans can be affected by a range of biases and systematics such as cosmological dimming and resolution effects. Then, Paulino-Afonso moved on to looking at the morphologies of a huge sample of Lyman Alpha emitters between redshifts ~2 and ~6, which can be the progenitors of present-day typical galaxies. These are usually different to the morphologies of nearby galaxies so the classification categories can be different and so can the biases found in human classifications. She analysed the data to gain a well-calibrated sample and also analysed the morphologies and attempted to understand why Lyman Alpha lines escape from their emitters. The scope of her work is to understand if being a Lyman-Alpha emitter is a phase through which galaxies may go through in the early stages of their life and which structural conditions boost the escape of Lyman-Alpha photons so that they enter our line-of-sight. As well as this, Paulino-Afonso is studying the changes in galaxy star-formation and morphology from low to high-density environments as well as the role that galactic filaments and the fraction of galaxies that are merging in different environments play in galaxy evolution.

In her opinion, “the best thing about doing research is having the opportunity to pose new questions every day and she is constantly amazed about what we do not know or do not fully understand about the universe and how to deal with the huge amount of data that we have. It makes every day different, which is amazing” and her advise to high school students looking to study physics and/or astrophysics at university is that physics and mathematics are tools that you will need, you should learn to code in the programming language that you feel most comfortable with, not to be worried about “bothering” people and most importantly to always stay curious.