OATS seminars

Past seminars

Postdoc Seminar

17 December 2025 • Contacto: Manuela Bischetti

Valeria Grisoni (INAF-OA Trieste) • Galactic archaeology: reconstructing the history of the Galaxy

In this talk, I will discuss the chemical evolution of the Milky Way in the light of the most recent data from Galactic surveys and missions. Currently, we are in a golden era for this field of research thanks to the advent of large spectroscopic Galactic surveys and projects, which are enhanced by the advent of ESA Gaia mission. In this way, detailed stellar abundances of stars in the Milky Way can be obtained. Moreover, stellar ages can give another fundamental constraint to reconstruct the history of the Galaxy. Then, by means of detailed Galactic chemical evolution models, it is possible to predict the chemical abundances expected in the stars of each Galactic component: halo, thick disc, thin disc and bulge. I will focus on the chemical bimodality between the Galactic thick and thin discs. I will start by discussing the dichotomy in the [alpha/Fe] vs. [Fe/H] diagram where we can clearly see two distinct sequences corresponding to the thick and thin discs, and then I will present new results in the light of new data for stellar ages. Finally, I will discuss new insights about the chemical evolution of the Milky Way from the point of view of zoom-in cosmological simulations of MW-like galaxies to further shed light on the formation and evolution of our home Galaxy, a Rosetta stone to understand galaxy formation and evolution.

Linda Lombardo (INAF-OA Trieste) • Neutron-capture elements in metal-poor stars: results from CERES and MINCE surveys

Metal-poor stars play a key role in understanding the nucleosynthesis of heavy elements in the early Universe, as their chemical abundances reflect the composition of the gas in which they formed. High-resolution spectroscopic studies show that very metal-poor stars exhibit a wide spread in the abundances of neutron-capture elements. This large star-to-star scatter seems to suggest that that multiple astrophysical sites contributed to their production, operating under different physical conditions. The nucleosynthesis processes and formation sites responsible for the production of neutron-capture elements in the early Galaxy are still a matter of debate, as several processes could be involved (e.g. s- process, r- process, i-process, weak r-process, weak s-process, ...). To trace the formation and evolution of heavy elements in the Milky Way we need detailed chemical abundances for a large sample of metal-poor ([Fe/H]<-1) stars, in order to compare them with the predictions of theoretical models. In this talk, I will present recent results from two projects, CERES and MINCE, which aim to characterise the nucleosynthesis and Galactic chemical evolution of heavy elements.

Recording

Roberto Raddi (Universitat Politècnica de Catalunya) • The fastest stars in the Milky Way

10 December 2025 • Contact: Nicola Gentile Fusillo

The Gaia mission has led to unprecedented advances in Galactic astronomy, including the identification and characterization of new classes of runaway stars. A few of them appear as chemically peculiar stars, with space velocities that exceed the escape speed of our Galaxy. These objects are suggested to be the lone survivors of thermonuclear supernovae that formed in a range of different scenarios. While we have only uncovered the "tip of the iceberg", the upcoming Gaia Data Releases, combined to the existing and future ground-based multi-object spectroscopic surveys can lead to more discoveries that will help us to characterize their wider population.

Recording

Pierluigi Selvelli (INAF-OA Trieste) • Fenomeni celesti e conseguenze terrestri in un testo del 1557 da poco riscoperto

4 December 2025 • Special Seminar (in Italian)

Nella recente pubblicazione "Gli incunaboli e le cinquecentine degli Osservatori astronomici dell' INAF (1478-1560)" figura un libro del 1557 "Prodigiorum ac Ostentorum Chronicon" di Konrad Lykosthenes, esemplare presente all'OAMI di Brera. Il testo in latino di 684 pagine, basato su circa 300 antichi riferimenti bibliografici e finora totalmente ignorato nei suoi contenuti astronomici, descrive fenomeni quali eclissi di Sole, comete, nuove stelle, tripli soli, aurore boreali, etc., fenomeni che nell'antichità venivano "naturalmente" associati a sciagure terrestri quali terremoti, siccità, carestie, epidemie, morti di sovrani, guerre. In questo seminario descriverò brevemente la parte medievale del libro vista nello specifico contesto sociale e culturale.

Recording (in Italian)

Marco Bersanelli (Università degli Studi di Milano; INAF-IASF) • The Planck heritage: towards the LiteBIRD space mission

3 December 2025 • Contact: Fabrizio Fiore

The Planck measurements of the cosmic microwave background (CMB) have firmly established the ΛCDM model as the standard cosmological framework for the coming decade. The mission’s remarkable precision resulted from a carefully integrated approach to instrument design, calibration, and observing strategy, all optimized to control instrumental systematics and astrophysical foregrounds. As LiteBIRD takes on the formidable challenge of measuring primordial CMB B-mode polarization, several aspects of the Planck experience offer a valuable legacy for meeting the mission’s stringent requirements.

Recording

José Caballero (CSIC–Centro de Astrobiología; European Space Agency) • Exoplanets from Spain

26 November 2025 • Contact: Giuseppe Murante

Astronomy in Spain was behind the rest of Europe for most of the 20th century. The first exoplanets were discovered in the 1990s, and the Spanish astronomers "watched the bullfight from the sidelines". In the early 2000s, there were a few "spontaneous" that discovered TrES-1 or rogue planets with masses near the deuterium burning mass limit in young open clusters, or that started working with CoRoT. In 2012, HARPS-N started operating at the 3.58 m Telescopio Nazionale Galileo in La Palma. HARPS-N "opened the gates of the bullring". Eventually, the bullfighters jumped into the arena and the bullfight began: CARMENES, ESPRESSO, James Webb and soon PLATO, CHORUS at the 10.4 m Gran Telescopio Canarias and Ariel. The future of Spanish exoplanet hunters is now very bright. A 'torero' will explain how Spanish exoplanet hunters managed to go from bullfighting young bulls to being maestros of exoplanet science.

Recording

Francesca Esposito (INAF-OA Capodimonte) • Back to the Moon - A window of opportunity for frontier Science

19 November 2025 • Contact: Fabrizio Fiore

In 2018, Space Agencies around the world published the Global Exploration Roadmap (GER), where they shared the common intent to expand the human presence into the Solar System with the surface of Mars as a driving goal and the Moon as a necessary intermediate step. About 30 robotic and 4 crewed space missions to the Moon (from 13 Countries and from both Space Agencies and private companies) have been already approved to be launched in the 2023 – 2028 time frame, while ~ 20 more missions are under evaluation. The goal of this space effort is to establish a sustainable human presence on the Moon and, in the future, also on Mars.

This seminar will discuss the strong effort ongoing worldwide and the important opportunities that could be offered in several sectors of science, technology, economics. The return to the Moon will revolutionize the relation of mankind to Space exploration. Experiments and facilities on the Moon, including new structures and devices for the observation of the Earth and the Universe, will boost planetary science, life science, physiology and medicine, radio, optical, infrared and cosmic ray astronomy, and more. The Moon has the potential to become the test ground for human capability to survive and operate in space, as well as a launch base for future planetary missions.

The role that Italy is playing in this context and the one it could play in the next future will be also discussed, with emphasis on INAF on-going activities.

Conrad Boehm (INAF-OA Trieste) • La compagnia del sestante: vita, ricerche, scoperte e avventure dei fondatori dell'Osservatorio

13 November 2025 • Special Seminar (in Italian)

Un gruppo di scienziati lavora assiduamente a Trieste dalla metà dell’Ottocento ai primi decenni del Novecento, nell’arco di tempo di tre generazioni. Inizialmente la loro opera è dedicata senza clamore alla conoscenza del cielo e alle applicazioni che l’astronomia offre alla navigazione, alla cronometria e alla dinamica dei corpi celesti, che insegnano ai giovani dell’Accademia di commercio e nautica, ma ben presto essi si rivolgono anche alla ricerca fondamentale, riscuotendo successi sempre più importanti fino a fondare un istituto di ricerca pura, l’Osservatorio astronomico. Fra avventure, genio e straordinaria dedizione la storia di questi uomini e del loro grande progetto, finora poco conosciuta, spalanca una finestra sulla storia di Trieste e ci illustra come la città della scienza affondi una possente radice nell’epoca dei nostri bisnonni.

Recording (in Italian)

Victor Debattista (University of Lancashire) • The In-situ Formation of the Milky Way’s Bulge

12 November 2025 • Contact: Gabriella De Lucia

The bulge of the Milky Way has long been thought to contain an accreted component. This is natural in a universe in which structure grows hierarchically. The rest of the bulge then is thought to have formed via secular processes involving the thickening of the bar. However the evidence put forth for such an accreted component fits better with an in-situ formation than a hierarchical formation. Here I show that evidence from kinematics, ages, morphology and chemistry can all be explained by in-situ processes, including not just those bar driven processes but also the effects of an early episode of clump formation.

Recording

Stefano Vercellone (INAF-OA Brera) • The ASTRI Mini-Array Project and its Scientific Goals

5 November 2025 • Contact: Paolo Di Marcantonio

The Universe is populated by extreme particle accelerators, capable of conveying more than 10^20 eV in a single proton. The gamma-ray photons they are able to produce could be used as probes to investigate the laws of Nature at the highest energies. To this aim, INAF is leading the international ASTRI Mini-Array Project. We are deploying and operating the first batch of nine dual-mirror, imaging atmospheric Cherenkov telescopes (IACTs) at the Teide Observatory at the Canary Island. The ASTRI Mini-Array energy range (1-200 TeV), wide field of view (10 degrees), angular resolution (3 arcmin at 10 TeV), and sensitivity (better than current IACTs above a few TeVs) are perfectly suited to investigate in depth ultra high-energy sources recently detected by LHAASO and HAWC up to a few PeVs, the so-called PeVatrons, shedding light on their nature. I will review the ASTRI Mini-Array project status, in particular focussing on its Galactic and extra-galactic scientific goals and its synergies with multi-wavelength facilities.

Recording

Sadegh Khochfar (Royal Observatory, Edinburgh) • Children of the Cosmic Web: How to Seed Super-massive Black Holes?

29 October 2025 • Contact: Umberto Maio

The James-Web-Space Telescope has revealed a large number of massive black holes in the early Universe. Their number density and mass relative to the stellar host pose challenges to our theoretical understanding of their formation. In my talk I will present results from recent high-resolution cosmological simulations on the seeding and feeding of black holes in the early Universe. I will discuss the competing conditions in the inter-stellar medium that lead either to star formation or black hole formation and reflect on how this compares to recent observations. I will further introduce a new seeding mechanism for black holes which relies only on turbulence driven by infall from the cosmic web and is a natural consequence of the LCDM structure formation paradigm.

Recording

Silvano Desidera (INAF–OA Padova) • The architectures of planetary systems

22 October 2025 • Contact: Laura Silva

A broad diversity in architectures of planetary systems is emerging from various planet search projects with different techniques and several statistical properties are consolidating.

A brief observational overview of the statistical properties of exoplanets will be presented, considering both giant planets and low-mass planets, with emphasis on multi-planet systems and systems somewhat resembling the architecture of the Solar System. The potential links with the characterization of planetar atmospheres will be highlighted. Finally, future perspectives based on new instrumentation from the ground and from space will be discussed.

Recording

Fabrizio Fiore (INAF-OA Trieste) • Space science & the space economy

15 October 2025

Will it be possible in the future to realize large, complex space missions dedicated to basic science like HST, Chandra and JWST? Today's space scenario is completely different from that of even five years ago, and certainly from that of the time when HST, Chandra and JWST were made. Space-related investments have grown exponentially in recent years, with monetary investment exceeding half a trillion dollars in 2023 and 2024. This boom is greatly aided by the rise of the so-called “new space” economy driven by private fundings, which for the first time last year surpassed public investments in space. The establishment of a market logic in space activities results in more competition, cost and time reduction. Can space science take advantage of the benefits of the new space economy to reduce cost and development time and at the same time succeed in producing powerful missions in basic science? The prospects for Europe and the USA are considered. We argue that this goal would be made possible if the scientific community could take advantage of the three pillars beyond the innovation of the new space economy: (1) technology innovation proceeding through both incremental innovation and disruptive innovation, (2) business innovation, through vertical integration and scale production, and (3) cultural innovation, through risk openness and iterative development.

Recording

David Mota (University of Oslo) • Nonlinear Cosmological Probes of screened gravity theories beyond General Relativity

8 October 2025 • Contact: Tiago Castro

Several modifications to general relativity have been proposed to explain the nature of dark energy and the accelerated expansion of the Universe. In this talk will review the current status of modified theories of gravity, focusing on astrophysical probes in the non-linear regime. I will begin by outlining the expected behavior of theories beyond General Relativity in various astrophysical systems and their cosmological signatures. With this foundation, I will present a range of observational tests, emphasizing the use of current and next-generation observations for testing gravity. Specifically, I will demonstrate how physical observables in the non-linear regime of structure formation serve as promising probes for constraining theoretical models in the nonlinear dynamics of galaxies, clusters, and large-scale structure.

Recording

Alessio Mucciarelli (Universita' di Bologna, INAF-OAS Bologna) • The chemical DNA of the Small Magellanic Cloud

1 October 2025 • Contact: Emanuele Spitoni

The Large and Small Magellanic Clouds (LMC and SMC) are the closest satellites of the Milky Way. Through their proximity and because individual stars can be resolved, the Magellanic Clouds provide a unique close-up of a pair of interacting dwarf galaxies. At variance with the LMC stars, whose chemical composition has been widely studied with high-resolution spectroscopy, the chemistry of the SMC stars has received less attention, despite the opportunity to study in details a metal-poor interacting galaxy.

In this talk I will present the results obtained by my team concerning the chemical composition of the SMC, using both field and globular cluster stars, with a particular attention to the elements produced through neutron-capture process.

Recording

Pedro Alonso Palicio (Observatoire de la Côte d'Azur) • Tracing the Milky Way’s Chemodynamics with Gaia [Seminar series]

26 September 2025 • Contact: Emanuele Spitoni

Lecture 3 • The Gaia mission has transformed our understanding of the Milky Way, revealing that it is no longer an isolated, axisymmetric system in equilibrium. The flared structures of the disc, kinematic disturbances in phase space, and remnants of accretion events are just a few examples of the many features unveiled by Gaia DR3. Since stars retain the chemical composition of their birthplaces, the chemical cartography of these structures provides unique insights into their formation, complementing the information obtained from purely kinematic analyses. In this lecture, I will present numerous examples where the chemistry and dynamics revealed by Gaia DR3 are interconnected, discuss their origins, and highlight the open questions that remain unresolved.

Lecture 4 • Although it is widely accepted that we live in a spiral galaxy, the location, population, and even the number of spiral arms remain controversial. These uncertainties arise from our position within the Milky Way disc, which prevents us from having a global view of the spiral structure, unlike external galaxies. To overcome this limitation, one must trace the spiral arms by means of more indirect methods, based on the imprints that the spirals leave on kinematics, dynamics, and chemistry, among other aspects. In this lecture, I will present recent detections of the Milky Way's spiral arms using Gaia DR3 data, with particular emphasis on those based on dynamics and subsequently

confirmed by numerical simulations.

Recording

Pedro Alonso Palicio (Observatoire de la Côte d'Azur) • Tracing the Milky Way’s Chemodynamics with Gaia [Seminar series]

25 September 2025 • Contact: Emanuele Spitoni

Lecture 1 • Although the Gaia mission was designed for the main goal of providing high precision astrometry, its satellite also contains the on-board spectrograph RVS, which operates in the wavelength range of the near IR calcium triplet, and collects spectral information for all-sky sources. Apart from determining radial velocities, this spectra allow us to characterise the stellar atmospheres and their chemical composition. To accomplish this task, the Gaia pipeline incorporates the GSP-Spec module (Recio-Blanco et al. 2023), which has provided the largest catalogue of its kind ever, totaling 5.6 million sources. In this lecture, I will present the spectral analysis performed by GSP-Spec, its products for Gaia DR3 and their best-usage practice for the proper interpretation of the scientific results.

Lecture 2 • The combination of astrometry and radial velocities from Gaia has provided full kinematic information for more than 30 million sources with unprecedented detail. This valuable dataset has revealed that our Galaxy is still evolving, exhibiting features incompatible with a system in equilibrium. To properly interpret these findings, it is essential to understand the key concepts of Galactic kinematics and dynamics. In this lecture, I will introduce the fundamental principles of Galactic kinematics and dynamics, starting from basic definitions and progressing to the state of the art. I will cover the main structural components of the Galaxy-bulge, disc, and halo-and illustrate how Gaia has contributed to major advances in this field.

Recording

Pedro Alonso Palicio (Observatoire de la Côte d'Azur) • Dynamics of the Spiral Arms as seen by Gaia

24 September 2025 • Contact: Emanuele Spitoni

Although it is widely accepted that we live in a spiral galaxy, the location, population, and even the number of spiral arms remain controversial. These uncertainties arise from our position within the Milky Way disc, which prevents us from having a global view of the spiral structure, unlike external galaxies. To overcome this limitation, one must trace the spiral arms by means of more indirect methods, based on the imprints that the spirals leave on kinematics, dynamics, and chemistry, among other aspects. In this talk, I will present recent results from the Galactic Archaeology group at the Observatoire de la Côte d'Azur concerning the detection of the Milky Way's spiral arms, with particular emphasis on those identified using Gaia DR3 radial actions and subsequently confirmed by numerical simulations.

Recording

Luca Zappacosta (INAF-OA Roma) • The rise of the titans: shedding X-ray light on the most luminous and distant quasars

17 September 2025 • Contact: Chiara Feruglio

Luminous quasars powered by supermassive black-holes (SMBH, M_SMBH=10^9-10^10 Msun) are excellent testbeds to probe the feedback mechanisms for AGN/galaxy co-evolution and BH formation models out to the first few billion years of cosmic evolution. In this talk I will focus on the nuclear properties of hyper-luminous (L_bol > 10^47 erg/s) quasars at Cosmic Noon (z=2-3) and in the Epoch of Reionization (EoR; z>6). I will show intriguing links between the X-ray coronal properties (luminosity, spectral slope) and the broad-line disk driven winds. In particular, I will show that the first luminous quasars at the EoR exhibit a markedly different and unreported regime in their X-ray properties with much steeper spectral slopes compared to similar quasars at lower redshifts. This is indicative of cold X-ray emitting coronae and is possibly related to the fast growth mechanism required to form SMBH in < 1 Gyr (i.e. during EoR). I will finally stress the relevance of our results in the JWST era and beyond in light of the future planned flagship X-ray observatories with survey programmes aimed at the z>6 Universe.

Recording

Fatemeh Zahra Majidi (Blue Skies Space) • Mauve: a three-year UV-Vis survey dedicated to monitor stellar activity and variability

10 September 2025 • Contact: Valentina D'Odorico

Mauve is a satellite equipped with a 13-cm telescope and a UV-Visible spectrometer (with an operative wavelength range of 200-700 nm) conceived to measure the stellar magnetic activity and variability. The science program will be delivered via a multi-year collaborative survey program, with thousands of hours each year available for long baseline observations of hundreds of stars, unlocking a significant time domain astronomy opportunity. Mauve’s mission lifetime is 3 years with the ambition of 5 years, and will cover a broad field of regard (–46.4 to 31.8 degrees in ICRS) during this period. Booked to launch on October 2025, Mauve’s science team will form prior to the launch date, defining the observation strategy and targets. The scientific themes selected for the first survey so far are: Monitoring multiple stellar systems, classical Be stars, young planet hosts, candidate targets for the Habitable World Observatory (HWO), stellar flares on solar analogs and cool dwarfs, coronal dimming associated with CMEs, and Herbig Ae/Be stars. Mauve is designed to foster innovative pilot studies and nurture emerging scientific ideas, with a dedicated focus on time-domain astronomy. Beyond its core scientific objectives, the data collected by Mauve can serve as a valuable resource for both supporting and enhancing current and future astronomical facilities, acting as a pathfinder and enabling coordinated or follow-up observations. In this presentation, I will provide the audience with a comprehensive update on Mauve’s progress from multiple perspectives, including: the completion of satellite construction, advances in scientific research and the implementation of major survey themes, and formation of the science team.

Recording

Recordings of less recent seminars can be found here.