Enrica Bellocchi: integral field spectroscopy and gas dynamics in active galaxies

From a small town in central Italy to leading research projects at one of Spain’s foremost universities, the trajectory of Dr Enrica Bellocchi traverses the great questions of contemporary extragalactic astrophysics. Trained in physics at the University of Bologna, awarded her doctorate in Madrid through a Marie Curie fellowship, and currently a researcher at the Universidad Complutense de Madrid, Bellocchi has established herself as an international reference in the analysis of integral field spectroscopy data applied to the study of luminous infrared galaxies, ionised winds from active galactic nuclei, and galactic feedback processes. 🔬 🛰️ In this conversation for SKYCR Dialogues she shares her academic path, her current research lines — including the Matrioska project on ultra-fast winds in galaxies hosting active nuclei —, her view on the future of astronomy in the era of the JWST and large surveys, and a firm reflection addressed to the new generations of researchers. 💫 A lucid look at the present state of observational astrophysics from scientific Madrid. 📖 We invite you to read the full interview.

Dark skies, an early vocation, and the solid foundation of physics

— Could you briefly introduce yourself to our audience and tell us about your academic and scientific trajectory up to your current work in astrophysics?

I was born in a small town in central Italy, where the dark skies and low light pollution awakened my curiosity about the stars and the universe from a very early age. I studied at the Liceo Scientifico, where I developed a strong interest in mathematics and physics, although for some time I hesitated about which path to follow, considering options such as Architecture, Chemistry or Physics. Eventually, I decided to study Physics at the University of Bologna, since it offered a solid and versatile foundation. With time, however, I felt the need to return to my true vocation, and so I continued with a master’s degree in Astrophysics, also at Bologna, at a stage when this specialisation was beginning to consolidate in Italy.

After completing my studies, I began my research activity working on simulations for the Large Binocular Telescope, which was at that time under construction and was emerging as one of the most advanced telescopes of its generation. Shortly afterwards, I obtained a doctoral position within a European Marie Curie network, which led me to move to Madrid. There I began my research career in astrophysics, focusing on the study of ultra-luminous infrared galaxies (U/LIRGs) using integral field spectroscopy data obtained with the VIMOS instrument at the Very Large Telescope (VLT), in Chile.

«Light does not only tell us that something is there, but also what it is like and what is happeninG»

I obtained my doctorate in 2014 and have since continued developing my research career in astrophysics. I currently work on the study of gas dynamics in active galaxies and the associated feedback processes, a key field for understanding the evolution of these galaxies. Throughout this journey, my family’s support has been fundamental in allowing me to pursue this path.

Decisions that shape a scientific career

— From your years of training to your postdoctoral stage, which moments or decisions do you consider most important in building your path as a researcher?

I believe there have been several key moments in my path as a researcher. One of the most important was deciding to study Physics rather than going directly to Astronomy. At that point I was looking for a more solid and versatile foundation, and over time I confirmed that this basis was fundamental for everything that came afterwards.

Another decisive point was daring to specialise in Astrophysics and follow a more personal vocation. That step truly marked the beginning of my scientific trajectory, because it was when I found the field that genuinely captivated me. The decision to go abroad to pursue my doctorate, thanks to a Marie Curie fellowship, was also very important. Moving to Madrid not only allowed me to work in an international environment and on highly competitive projects, but also helped me grow significantly at a personal and professional level.

Finally, during my postdoctoral stage, I would highlight the choice of my research lines, focused on the study of galaxies and feedback processes. That was where I began to consolidate a scientific identity of my own.

The appeal of observational work and spectroscopy

— Your profile shows experience in Spitzer data analysis, data reduction with VIMOS/VLT and integral field spectroscopy. What particularly drew you to this type of observational and analytical work?

What attracted me most about observational work and data analysis was the possibility of directly connecting physics with the real universe. That is, not working solely with theoretical models, but interpreting data from actual objects such as galaxies or regions of star formation. Spectroscopy in particular fascinated me because it allows one to extract a great deal of physical information — such as the velocities of gas and stars, the chemical composition or the conditions of the interstellar medium — from light alone. It is, in a way, a means of decomposing the information of the universe in order to understand in detail what is happening.

Furthermore, I find the combination of skills this type of work requires very interesting: on the one hand, the technical component, which includes the reduction and analysis of data from complex instruments such as VIMOS at the VLT, or data from space observatories such as Spitzer, and on the other hand, the physical interpretation of the results. Throughout my career I have also worked with other integral field spectroscopy instruments, such as MUSE at the VLT or MEGARA at the Gran Telescopio Canarias, which provide increasingly detailed information thanks to their higher spectral resolution.

Finally, something I particularly value is the need to be rigorous and critical with the data, fully understanding their limitations. That combination of technique, analysis and physical interpretation is what makes this work especially motivating. Moreover, with the arrival of new space telescopes such as the James Webb Space Telescope (JWST), we are accessing unprecedented data that allow us to study increasingly distant galaxies at extraordinary levels of detail.

Integral field spectroscopy, explained with clarity

— For those unfamiliar with these techniques, how would you explain the importance of spectroscopy and, in particular, of integral field spectroscopy in the study of galaxies and other astrophysical objects?

For those unfamiliar with these techniques, spectroscopy is a tool that allows us to decompose the light of astronomical objects, as if it were a rainbow. From that decomposition we can extract very valuable information, such as the chemical composition, the velocities of the gas, or the physical conditions within galaxies. In other words, light not only tells us that something is there, but also what it is like and what is happening.

«The ionised wind associated with an active nucleus can not only expel gas but, under certain conditions, can also compress it and induce star formation in the companion galaxy»

Integral field spectroscopy goes one step further, since it allows us to obtain this information not at a single point, but across an entire region of the object simultaneously. In practice, we obtain a spectrum at each position of a galaxy, which enables us to build two-dimensional maps of its physical properties, such as gas velocity, gas distribution or zones of star formation. It is like moving from a single measurement to a complete view, almost like a film of what is happening across the entire galaxy.

The type of galaxies we can study depends both on the spatial resolution of the instrument and on its field of view and the distance at which the objects lie. Distant galaxies appear smaller to us not because they necessarily are, but simply because they are farther away, in the same way that an object looks smaller the greater the distance. Instruments such as MUSE at the VLT allow us to observe relatively wide areas of the sky with great sensitivity, which is ideal for studying nearby galaxies as a whole. In the future, telescopes such as the Extremely Large Telescope (ELT), with a primary mirror of around 39 metres, will allow us to study far more distant galaxies with unprecedented levels of detail.

Stages at UCM, CSIC-INTA, and UAM: what each centre contributes

— Throughout your career you have passed through institutions such as UCM, CSIC-INTA and UAM. What has each of those stages given you in scientific, human and professional terms?

Throughout my career, each stage has contributed not only at a scientific level, but also at a human and professional one. I carried out my doctorate at the Centro de Astrobiología, where I acquired a very solid foundation in research and in data analysis techniques. At a human level, it was a key stage for learning to work in a team, to manage the uncertainty inherent to research, and to develop perseverance.

I then spent a couple of years at the Universidad Autónoma de Madrid, where I broadened my academic and teaching experience. This stage helped me to improve my communication skills and to appreciate the importance of student training as part of scientific work. Subsequently, I returned to the Centro de Astrobiología with several contracts, which allowed me to consolidate my research lines. At a human level, it was also important for strengthening collaborations and building more enduring scientific relationships.

Finally, at the Universidad Complutense de Madrid I have reinforced both my collaborations and my scientific leadership, developing projects of my own. Additionally, during this stage I teach undergraduate and master’s students, which has allowed me to consolidate my teaching and communication skills as well. Taken together, this trajectory has allowed me to grow not only as a researcher, but also in my capacity to work with others, communicate science, and adapt to different environments.

Challenges with complex observational data and a discovery published in Nature

— What have been some of the most important challenges you have faced when working with complex observational data, and how have you addressed them?

During my doctoral thesis I worked with pioneering VIMOS/VLT data on a broad sample of ultra-luminous infrared galaxies (U/LIRGs). At that time, virtually no previous studies existed using integral field spectroscopy for this type of object, which posed a significant challenge both technically and in terms of interpretation. One of the main challenges was the analysis of complex spectra, which required multi-component fits in order to separate the different contributions of the gas. To address this, I developed a very methodical approach, carefully validating the fits and comparing different solutions to ensure the robustness of the results.

This work led me to identify particularly interesting cases, such as the galaxy IRASF23128-5919, an interacting system of two galaxies. From there, we pushed forward new observations with the X-shooter/VLT instrument, in collaboration with a group at Oxford. This made it possible to obtain a particularly relevant result, subsequently published in the journal Nature, since we found evidence that the ionised wind associated with an active nucleus can not only expel gas but, under certain conditions, can also compress it and induce star formation in the companion galaxy, providing observational evidence for positive feedback scenarios. Overall, this experience taught me the importance of combining technical rigour with critical data interpretation, especially when working in poorly explored areas.

Fundamental skills for observational astrophysics today

— In your experience, which skills are fundamental today for someone who wishes to pursue observational astrophysics and advanced data analysis?

I would say that the fundamental skills in observational astrophysics and data analysis are a combination of technical and personal competencies. On the one hand, it is essential to have a good foundation in data analysis, programming and understanding of instruments and their limitations, since we work with complex data from telescopes such as the VLT or the JWST space telescope. In addition, we also work with major current galaxy surveys such as MaNGA, CALIFA and SAMI, which generate increasingly massive volumes of data.

On the other hand, at a personal level, determination and patience are essential, because research is not linear: the data are complex and results usually require several iterations before reaching a robust interpretation. In this sense, one needs to be persistent and to maintain a flexible attitude in the face of problems. Overall, I would say that technical rigour, critical thinking, and resilience are the keys to this field.

Matrioska: ultra-fast winds in galaxies hosting active nuclei

— Is there any project, result or research line in particular of which you feel especially proud and that you would like to highlight?

Throughout my career I have had the opportunity to work with leading researchers and in highly stimulating scientific environments, which has been key to my development as a researcher. In particular, I have built extensive experience in the analysis of integral field spectroscopy data, a powerful technique that is currently allowing us to obtain ever more detailed results on the structure and dynamics of galaxies.

I would particularly like to highlight a project I am currently leading at the Universidad Complutense de Madrid, called Matrioska. This project focuses on the study of nearby galaxies hosting active nuclei with ultra-fast winds (Ultra Fast Outflows), initially detected in X-rays and with velocities close to significant fractions of the speed of light. The objective is to study how these winds propagate at different scales, from very central regions close to the active nucleus to scales of several kiloparsecs, and how they interact with the interstellar medium, generating winds in different phases, such as the ionised and the molecular. To this end we use integral field spectroscopy data, which allow us to map these processes in detail, particularly in the ionised gas.

«It is essential that female students do not allow themselves to be conditioned by stereotypes or by the perception that these careers are not for them»

This is a research line under active development, combining high-quality observations with modelling and simulations, and is being driven forward by the new generations of IFU instruments in the optical and the infrared (JWST).

The great questions of contemporary extragalactic astrophysics

— From your perspective, which are some of the most interesting questions that extragalactic astrophysics and spectroscopy are currently helping to answer?

From my perspective, extragalactic astrophysics, together with spectroscopy, is experiencing a moment of enormous progress. We are increasingly understanding what galaxies are like and how they evolve, including the most distant ones, and accessing physical details that were previously inaccessible. In this context, one of the great questions today is how galaxies form and evolve across cosmic time, and which processes regulate their growth. In particular, the role of gas, star formation, and feedback from active nuclei are fundamental issues.

Another key question is precisely the role of active galactic nuclei (AGN) in galaxy evolution. Thanks to integral field spectroscopy, we are beginning to be able to study not only the central region, but also how the energy released by these nuclei propagates on galactic scales and how it interacts with the interstellar medium, possibly inhibiting or even favouring star formation in certain cases. Finally, another very important question is how gas is distributed and how it moves within galaxies. Spectroscopy allows us to map the kinematics of gas and stars in detail, which is essential for understanding processes such as mergers, accretion or outflows.

Integral field spectroscopy plays a key role in this progress, as it allows us to move from a global view of galaxies to a spatially resolved view of their physical properties. A striking example is the JWST space telescope, which is providing observations of very distant galaxies with unprecedented sensitivity and resolution in the infrared, opening a new window onto the study of the earliest stages of galaxy formation.

The future: big data, JWST, and more sophisticated analysis techniques

— How do you see the evolution of astronomical research in the coming years, especially in relation to the growth of large databases, new instrumentation and more sophisticated analysis techniques?

I see the evolution of astronomical research in the coming years as a transition towards a science increasingly based on large volumes of data and on the intensive use of advanced computational tools. On the one hand, we are entering an era in which large surveys and new instruments, both ground-based and space-based, will generate unprecedented quantities of data. This entails not only storing information, but also developing infrastructures and efficient strategies for its management, access, and analysis, so that the scientific community can exploit it optimally.

In this context, databases and archive projects already exist and will continue to be fundamental, but the challenge is not only storage, but the capacity to extract relevant physical information efficiently and robustly. On the other hand, this is driving the development of increasingly sophisticated analysis techniques, including advanced statistical methods, machine learning, and automated reduction and analysis pipelines. All of this is especially relevant in fields such as integral field spectroscopy, where the complexity of the data is very high.

I believe astronomy is evolving towards a more interdisciplinary model, where physics, computer science, and data analysis are increasingly integrated, which opens very interesting opportunities but also new challenges in terms of interpretation and scientific quality control.

What still inspires after years of research

— On a more personal level, what continues to inspire you most about astrophysics after years of training, research and postdoctoral work?

What continues to inspire me most about astrophysics is precisely that there is always something new to discover and understand. It is a field in which science is in continuous evolution, and each new generation of instruments or techniques opens entirely new windows onto the universe. In particular, I am motivated by being able to connect increasingly detailed observations with the physical processes that generate them, and by working on questions that still remain open about galaxy formation and evolution.

I feel astrophysics combines constant curiosity very well with the intellectual challenge of interpreting complex phenomena, and that is what continues to motivate me after all these years of training, research, and postdoctoral work.

Advice for the new generations

— What advice would you give to young students or to future researchers who dream of pursuing astrophysics professionally?

My main advice to young students is to follow their curiosity and motivation in any field. Astrophysics is a demanding path, but a very enriching one. I also believe it is important to point out that a certain gender bias still exists in scientific careers, especially in the early stages of training and in some areas of science, where women remain under-represented. For that reason, it is essential that female students do not allow themselves to be conditioned by stereotypes or by the perception that these careers are not for them.

Whenever I have had the opportunity, I have promoted the visibility of women researchers from different countries and trajectories, inviting many female scientists to share their work in talks and outreach activities. In my own personal experience, I have never felt that being a woman was a limitation for dedicating myself to science, but I do believe it is important to continue working so that access and visibility are truly equitable. In any case, the most important things are passion, perseverance, and the capacity to face a path that is long and at times uncertain, but also deeply rewarding.

A final reflection on the value of exploring the universe

— Is there any message or reflection you would like to share with our audience about science, research or the value of exploring the universe?

I believe we are very fortunate to be part of a system as complex and fascinating as the Earth within the Universe that surrounds us. A system at once extraordinary and fragile, which we are beginning to understand more deeply thanks to science. In recent years we have seen very important advances in astrophysics and space exploration, with missions that allow us to observe the cosmos with unprecedented levels of detail and to study very distant galaxies, continually expanding our view of the Universe.

For me, one of the most inspiring aspects of science is human curiosity: the ability to ask ourselves questions and seek answers about our origin and our place in the cosmos. That curiosity has been the engine of the great scientific advances throughout history. For that reason, I would especially like to encourage the new generations to keep that curiosity alive and not to be discouraged in the face of challenges, because research is a path that requires time, effort, and perseverance, but also offers enormous rewards. Ultimately, understanding the Universe is also a way of understanding ourselves and of placing ourselves within a far broader context, which is what makes research in this field especially valuable.

Editorial reflection

The conversation with Dr Enrica Bellocchi leaves a precise portrait of what it means today to practise observational astrophysics at the highest level: a discipline that no longer rests on telescope power or theoretical elegance alone, but on the capacity to read, with almost forensic rigour, the data that light carries from impossible regions of the universe. Her trajectory — from Bologna to Madrid, from the simulations of the Large Binocular Telescope to the leadership of the Matrioska project — illustrates a way of building a scientific career that depends neither on shortcuts nor on media visibility, but on formative decisions made with judgement: studying Physics before Astronomy, weathering the uncertainty of a doctorate abroad, and sustaining research lines of her own over years until they begin to address the right questions.

There is a particularly significant point in her testimony, and it deserves emphasis. When Bellocchi discusses the result published in Nature on the system IRASF23128-5919 — where the ionised wind from an active nucleus not only expels gas but also compresses it and induces star formation in the companion galaxy — what she describes is not an isolated finding, but a subtle shift in the way galactic feedback is understood. For years, AGN feedback was interpreted almost exclusively as a destructive mechanism, a brake on star formation. The evidence that she and her group contributed displaced that reading: under certain physical conditions, the same mechanism can be constructive. That kind of nuance, which rarely survives in press headlines, is precisely what integral field spectroscopy is now enabling — and what the JWST, with its unprecedented sensitivity in the infrared, is extending into cosmological regimes that were unreachable only a few years ago.

It is also worth attending to what her voice contributes beyond the strictly technical. Her appeal to the new generations — and especially to female students who wonder whether science is for them — is delivered without stridency, but with a clarity that bears retaining: gender bias in astrophysics is not resolved through declarations, but through real visibility, sustained mentorship, and documented trajectories. SKYCR.ORG takes on that responsibility as part of its editorial mission: to give space to women researchers who are building, today, the body of knowledge that the coming decades will take for granted. Dr Bellocchi is, in that sense, precisely the kind of reference that the Spanish-speaking astronomical community needs to know better.

— Homer Dávila Gutiérrez, FRAS