Seminari OATS

Seminari passati

Antonio Pensabene (DAWN/DTU Space) • The efficient assembly of galaxies and black holes in a massive node of the Cosmic Web at z~3

6 maggio 2026 • Contatto: Francesco Salvestrini

Galaxies form and evolve within the densest structures of the Universe, where they are fed by filamentary gas inflows from the Cosmic Web. However, the mechanisms regulating gas accretion and its impact on galaxy evolution remain poorly understood. A recent VLT/MUSE survey around a z~3 quasar provided one of the first direct images of contiguous Cosmic Web filaments on megaparsec scales, converging into a massive node rich in galaxies and AGN. This structure offers a unique laboratory to study the interplay between large-scale environments, galaxy assembly, and black hole growth in the densest regions of the early Universe. In this colloquium, I will present multi-wavelength observations toward this Cosmic Web node, uncovering a remarkable overdensity (>10–100) of heavily dust-obscured, gas-rich star-forming galaxies, accompanied by a high fraction of X-ray detected AGN. We further identified extreme systems, including a dynamically cold companion galaxy interacting with the central hyperluminous quasar, the largest spiral disk galaxy known at this epoch, and a massive quenched galaxy embedded within actively accreting filaments. Together, these findings indicate that dense Cosmic Web nodes at z~3 efficiently funnel gas toward galaxies and their nuclei, promoting rapid galaxy assembly and accelerated supermassive black hole growth compared to field environment.

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Carmelita Carbone (INAF-IASF Milano) • Late-time cosmological signatures of massive neutrinos and dark energy with the DEMNUni project: from cosmic voids to secondary CMB anisotropies

29 aprile 2026 • Contatto: Stefano Borgani

Massive neutrinos and dark energy both leave measurable imprints on the late-time growth of cosmic structure, but exploiting these effects requires accurate modelling of the non-linear regime and of observables sensitive to evolving gravitational potentials and underdense environments. In this talk, I will present recent results from the DEMNUni project, a suite of large-volume numerical simulations designed to investigate the impact of massive neutrinos and dynamical dark energy on structure formation and cosmological observables. I will focus in particular on two complementary classes of late-time probes: cosmic voids and secondary CMB anisotropies. On the void side, I will discuss how massive neutrinos and dark energy affect void abundance, the void size function, the halo mass function and halo bias inside voids, and the cross-correlation between voids and CMB lensing. On the CMB side, I will review DEMNUni results on the non-linear Integrated Sachs–Wolfe/Rees–Sciama effect, its cross-correlations with galaxy clustering and CMB lensing, and more recent extensions to Sunyaev Zel’dovich observables. These studies illustrate how late-time probes can help disentangle the effects of neutrino mass and dark energy, and highlight the broad role of DEMNUni as a laboratory for precision cosmology beyond the minimal ΛCDM scenario.

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Maurizio Busso (Università di Perugia) • Does Nucleosynthesis Occur in Single Low Mass Stars? (And if so, when and how?)

22 aprile 2026 • Contatto: Francesca Matteucci

In this talk I review the growth of our understanding of the advanced evolutionary phases of single, low mass stars (M < 4M8) that contribute in a crucial way to the nuclear evolution of the cosmos, while hosting strangely-looking cores, made of a Fermi gas (that we call degenerate cores). The existence of such stars was discovered by Merril in 1952 from spectroscopy; the physics of their cores had been previously described in 1935 by S. Chandrasekhar and their nuclear processes started to be understood after the works by Cameron (1955) and by Burbidge, Burbidge, Fowler and Hoyle (1957). I shall then outline the slow steps done afterwards, which now allow us to know rather well their peculiar physical behavior and their nuclear processes, dominated by slow neutron captures. In so doing, I shall also remark how well we can now determine experimentally the probabilities of such captures (through their neutron capture cross sections). After several decades of uncertain debates, we can now also predict in a consistent way their nucleosynthesis outputs, whose temporal evolution finds now a beautiful confirmation in recent models of the Chemical Evolution of Galaxies (for which this observatory and the Trieste physical department are world-wide famous). In them, wide samples of stellar observations and of stellar nucleosynthesis models can be joined, in a successful attempt of understanding how common baryonic matter becomes complex in our universe.

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Stefano Zarattini (CEFCA) • Growing Along the Cosmic Web: Insights from BCG-Cluster-Filament Alignments in J-PLUS

16 aprile 2026 • Contatto: Marisa Girardi • Seminario speciale

In the first part of this talk I will briefly introduce CEFCA and update the status of the J-PLUS and J-PAS surveys, focusing on how they can help your own science and presenting the Open Time Legacy Survey at JST250, a unique opportunity to observe with the 2.5m telescope and the J-PAS filter set your favourite scientific target.

In the second part, I will discuss the importance of large-scale alignments, using a sample of 2018 galaxy clusters identified in the RedMaPPer catalogue that are also available in the J-PLUS footprint. For these clusters, we measured the global position angle (P.A.) by modelling the distribution of member galaxies with an elliptical shape. Moreover, we computed the P.A. of each brightest cluster galaxy (BCG) using the GNUASTRO code. We then estimated the excess of aligned BCGs and used the power of J-PLUS to investigate how the properties of the BCGs (stellar mass, global and recent star-formation rate, and dominance) correlate with the alignment signal. Finally, we used the catalogue of filaments and nodes from Chen et al. (2016) to study the alignment between clusters/BCGs and their closest cosmic filaments.

We find an excess of small P.A. differences between BCGs and clusters, thus confirming previous results from the literature. The alignment signal is stronger for massive and dominant central galaxies, suggesting that this result is more closely linked to the intrinsic properties of the BCGs than to those of the host halo. Moreover, an excess of alignment is also found between clusters and filaments. The alignment signal appears to be robust against environmental variations. Specifically, splitting the sample by richness or distance to cosmic structures reveals a persistent excess that does not scale significantly with these quantities.

These results suggest that the alignment between BCGs and their host clusters reflects the anisotropic assembly history of the most massive central galaxies, which have preferentially grown along the directions defined by the cosmic web. This points to a tight co-evolution between BCGs and large-scale structure, with implications for our understanding of BCG formation and the role of environment in shaping galaxy properties.

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Nicolas Bouché (Centre de Recherche Astrophysique de Lyon) • The impact of stellar feedback on the halos of galaxies

15 aprile 2026 • Contatto: Paramita Barai

SN-driven stellar feedback plays a major role in shaping galaxies, and is thought to play a major role in regulating the evolution of star-forming galaxies. These outflows directly impact the baryonic content of halos around galaxies, or the circum-galactic medium. These outflows are also thought to directly impact the shape of dark-matter halos, transforming steep cuspy profiles into cores. In this talk, I will present the latest results on these fronts from two major MUSE surveys: (1) MUSE-DARK survey and (2) the MUSE-gas survey of fields with background quasars.

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Matteo Pinamonti (INAF-OA Torino) • Gaia astrometry and the exoplanet populations

9 aprile 2026 • Contatto: Paolo Simonetti • Seminario speciale

Understanding the demographics of substellar companions in the transition mass regime between giant planets (GPs) and brown dwarfs (BDs) is today one of the key open questions in exoplanetary science. Despite the discovery of thousands of GPs and BDs, the statistics on their occurrence and properties are still very incomplete. In this seminar, I present a novel simulation framework, validated against Gaia DR3, designed to map the demographics of giant planets (GPs) and brown dwarfs (BDs) ahead of the DR4 and DR5 releases. Focusing on a volume-limited sample of nearby M dwarfs, I estimate Gaia's ability to recover substellar signals through epoch astrometry. These results demonstrate how the extended observational baseline and improved precision of future releases will transform our understanding of system formation. By providing a robust census of outer giants, this work establishes the statistical context necessary to constrain orbital dynamics and water delivery, ultimately defining the environmental potential for habitability in nearby exoplanetary systems.

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Glenn van de Ven (University of Vienna) • The colourful past and dark side of galaxies unveiled through population-dynamics of their stars

8 aprile 2026 • Contatto: Fabio Fontanot

Driven by gravity, galaxies continuously grow through accretion of smaller systems. Stellar streams are nice illustrations of this hierarchical build-up, but the accreted stars quickly disperse. I will present advanced dynamical models that convert the observed positions and velocities of stars to phase-space quantities like (orbital) energy and angular momentum which retain a dynamical memory of their past. In addition, these models can include the observed ages and chemical properties of stars which are conserved. The resulting population-dynamical models allow us then to uncover even those accretion events which are now fully dispersed. At the same time, these models also accurately constrain the total mass distribution, including a central black hole and dark matter halo. I will illustrate how these models make optimally use of observations to unveil the dark side and colour past of galaxies: from accurate measurements of their central black holes and extended dark halos, to unveiling the formation history of their disks, to uncovering ancient massive mergers and accreted satellite galaxies. Together with direct coupling to state-of-the-art galaxy formation simulations, these population-dynamical models enable us to uncover the hierarchical build-up of galaxies in a cosmological context.

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Anna Francesca Pala (ESO Garching) • Accreting white dwarfs as astrophysical probes

1 aprile 2026 • Contatto: Nicola Gentile Fusillo

Thanks to their large numbers, proximity, and brightness, accreting white dwarfs are ideal laboratories for refining the models of binary evolution, unveiling the pathways to Type Ia Supernova explosions, and characterising the Galactic binary foreground that will limit the sensitivity of the LISA space mission. Shedding light on the evolution and final fate of accreting white dwarfs is thus crucial across several astrophysical contexts. In this talk, I will discuss how the synergy between the largest ground-based telescopes, the Hubble Space Telescope, and the ESA Gaia space mission, allowed us to (i) derive masses and accretion rates for a large sample of accreting white dwarfs, and (ii) build the largest volume-limited sample of accreting white dwarfs within 300 pc. Thanks to these results, we have revealed the presence of an anti-correlation between the average accretion rates and white dwarf masses, and shown that the observed space density is about 1-2 order of magnitude lower than predicted. These findings provide observational evidences for the presence of an additional mechanism of angular momentum loss not accounted for by most evolutionary models, and I will present these results in the context of the current models of compact binary evolution.

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Alessia Gualandris (University of Surrey) • Dynamical evolution of supermassive black hole binaries in massive elliptical galaxies

31 marzo 2026 • Contatto: Marisa Girardi • Seminario speciale

Recent results from pulsar timing arrays (PTAs) show evidence for a gravitational wave background (GWB) consistent with a population of unresolved supermassive black hole (SMBH) binaries (BHBs). Such binaries represent the loudest sources of gravitational waves (GWs) in the Universe. The amplitude of the GWB results from several factors including the galaxy merger rate, the BHB merger rate, MBH-galaxy scaling relations, the evolutionary timescale of BHBs from pairing to coalescence and gas accretion processes. Of these, the evolutionary timescale of BHBs is particularly uncertain. I will present numerical studies of the evolution of massive black hole binaries formed in gas poor galactic mergers, typical of massive elliptical galaxies and the likely hosts of PTA sources. I will review the physical processes driving the evolution of such binaries from the largest scales of the merger down to the smallest scales of GW emission and coalescence. A key parameter affecting estimates of the merger rate is the eccentricity with which a binary forms, a highly stochastic quantity. I will show how this varies over the different evolutionary phases prior to coalescence and I will present numerical challenges in modelling black hole binaries to produce reliable estimates of GW merger rates.

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Stefano Sandrelli (INAF-OA Brera) • L'Office of Astronomy for Education Center Italy: che cosa è, che cosa fa e perché lo fa in quel modo

26 marzo 2026 • Contatto: Giulia Iafrate • Seminario speciale

Fondato nel marzo 2021, l'Office of Astronomy for Education Center Italy (I-OAE) è un ufficio internazionale della IAU, coordinato e finanziato da INAF. I-OAE promuove e sostiene pratiche di insegnamento innovativo, centrato sulla persona, e di corsi di formazione docenti. Nei suoi primi anni di esistenza, I-OAE ha sviluppato processi collaborativi, a cui hanno partecipato rappresentanti di Albania, Cipro, Croazia, Egitto, Francia, Grecia, Israele, Italia, Marocco, Montenegro, Palestina, Portogallo, Slovenia, Siria, Spagna e Turchia. Non solo il network è in costante crescita, ma si sta dimostrando anche di attrarre fondi europei. I-OAE coordina anche l'edizione internazionale di astroEDU, la piattaforma di attività didattiche peer-reviewed della IAU. I-OAE è un ufficio aperto alla collaborazione di volontari che ne condividano valori e metodi.

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Francesco Calura (INAF-OAS Bologna) • Star-by-Star Cluster Formation in Cosmological Simulations

25 marzo 2026 • Contatto: Gabriele Cescutti

Recent JWST observations have opened a new window on star clusters and compact star-forming systems in the early Universe, revealing structures whose interpretation demands unprecedented resolution in cosmological models, down to sub-parsec scales where gravity, gas dynamics, and stellar feedback are tightly coupled. In this talk, I will present results from the SImulating the Environment where Globular clusters Emerged (SIEGE) project, a new suite of extremely high-resolution hydrodynamic cosmological simulations designed to follow cluster formation at sub-parsec resolution, including star-by-star stellar feedback within a cosmological framework. By modelling feedback from individual massive stars, we capture the highly inhomogeneous and time-dependent processes that regulate gas accretion, cluster growth, and early dynamical evolution. These unprecedented features open a new regime for connecting theory and observations. In particular, we generate realistic mock observations tailored to the capabilities of upcoming facilities such as the ELT, providing forward-modelled predictions for the resolved imaging of compact stellar systems at high redshift.

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Simon White (MPA Garching) • A puzzle solved: the world is flat

18 marzo 2026 • Contatto: Gabriella De Lucia, Stefano Cristiani

The first measured extragalactic redshift, that for M31, showed that our giant neighbour is approaching the Milky Way at 100 km/s. In the 1920's it became clear that other galaxies, only slightly farther away, almost all move away at speeds that are closely proportional to their distance. This has resulted in a mismatch between the relatively large mass inferred for the Local Group from the motions of its two big galaxies, and the relatively small mass required to avoid excessive perturbation of the local Hubble flow. I will present the solution to this century old puzzle.

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Fabrizio Bocchino (INAF-OA Palermo) • From Autopsy to Diagnosis: Direct Detection of Episodic Mass Loss in SN Progenitors in the LSST Era

4 marzo 2026 • Contatto: Michele Maris

Red Supergiants (RSGs) are the canonical progenitors of Type IIP/L supernovae. While standard stellar evolution models depict them as quiescent stars undergoing steady-state mass loss, this picture is increasingly challenged by evidence of complex, dense circumstellar material (CSM) surrounding the explosion site. These interaction signatures indirectly point to intense, episodic mass-loss events occurring shortly before core collapse, the physics of which remain an open question. In this talk, I discuss a shift in observational strategy: moving from the forensic "autopsy" of supernova light curves to the "diagnosis" of the living progenitor. I will present results from a targeted optical/NIR monitoring campaign designed to detect these precursor outbursts, aiming to characterize the final evolutionary stages of massive stars before the terminal explosion.

Registrazione (in inglese)

Laura Abrami, Giulia Delbello (INAF-OA Trieste) • Pubblicare OA @ INAF: come avvalersi dei contratti trasformativi

26 febbraio 2025 • Seminario speciale

Il seminario si propone di illustrare i concetti chiave legati alla pubblicazione ad accesso aperto degli articoli scientifici. In particolare, sarà affrontato il tema dei contratti trasformativi sottoscritti dalla nostra Istituzione, con l’obiettivo di chiarirne il funzionamento e le opportunità concrete per il personale INAF. Verranno illustrati i principali aspetti pratici dei contratti, con approfondimenti sulle modalità di pubblicazione previste da ogni singolo accordo siglato attraverso CRUI.

L’incontro introdurrà, inoltre, i principi base dell’Open Access, fornendo gli strumenti essenziali per un utilizzo consapevole delle risorse disponibili in INAF.

Alberto Pellizzoni (INAF-OA Cagliari) • Solaris: Towards a Global Network for High-Frequency Radio Monitoring of the Sun

11 febbraio 2026 • Contatto: Fabrizio Fiore

Building on the solar observation expertise gained with INAF’s large radio telescopes, Solaris is a technological, scientific, and applied project aimed at developing an innovative solar monitoring system at high radio frequencies, based on single-dish imaging techniques.

Solaris integrates dedicated, interchangeable high-frequency receivers onto small-aperture radio telescopes already operational at laboratories in mid-latitudes and Antarctica, specifically optimized for tracking and observing the solar disk. By leveraging the exceptional atmospheric opacity conditions of the Antarctic site during the summer season, Solaris enables an observational duty cycle of nearly 20 hours per day. Currently, it represents the only observational asset capable of providing continuous solar monitoring in the 18–100 GHz range.

Looking ahead, extending the network to the Northern Hemisphere and creating synergies with other national observational resources would allow for global, uninterrupted coverage of the solar chromosphere and corona year-round. This would enable Space Weather services that can be integrated into national and international networks to mitigate geomagnetic risk. Results from the first Antarctic test campaign have confirmed the system's effectiveness: over 100 radio maps at 95 GHz were acquired, allowing for the identification and evolutionary monitoring of active regions characterized by intense flares, coronal mass ejections (CMEs), and subsequent terrestrial geomagnetic storms.

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Darko Donevski (National Centre for Nuclear Research, Warsaw; SISSA) • Towards a Complete View of Dust, Gas, and PAHs in the Late Phases of Galaxy Evolution

4 febbraio 2026 • Contatto: Chiara Feruglio

Investigating dust and gas in quiescent galaxies (QGs) is rapidly emerging as a new subfield of galaxy evolution, opening a key complementary window on how galaxies age once star formation has ceased. This shift is driven by growing evidence for significant dust and molecular gas in QGs and their environments out to z ~ 4, which challenges the long-standing view that these components are rapidly destroyed in hostile environments such as the quenched ISM and CGM of massive galaxies.

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Armando Riccardi (INAF-OA Arcetri) • The ERIS instrument at VLT: development, commissioning and results of the adaptive optics module

28 gennaio 2026 • Contatto: Paolo Di Marcantonio

ERIS is a new Adaptive Optics (AO) instrument that has been operating at the Cassegrain focus of VLT-UT4 since April 2023. It was developed by a consortium including the Max-Planck-Institut für Extraterrestrische Physik, UK-ATC, ETH-Zurich, NOVA-Leiden, ESO, and INAF. The ERIS AO system, developed by INAF-OAA, offers an NGS mode for high-contrast correction and an LGS mode to extend high-Strehl performance across wide sky coverage. The AO module features a 40x40 LGS wavefront sensor (WFS) and an NGS WFS capable of switching between 40x40 and 4x4 configurations. It also includes relay optics for the telescope beam and a dedicated SPARTA real-time computer running the AO loop at up to 1 kHz. Working with the 1170-actuator Deformable Secondary Mirror and the VLT-AOF Laser Facility, the AO module provides correction for the NIX high-resolution coronagraphic imager (1-5 µm) and the SPIFFIER IFU spectrograph (1-2.5 µm). In this talk, we review the ERIS AO system design drivers, major development milestones, and commissioning achievements, along with a brief selection of science results.

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Silvia Belladitta (MPIA Heidelberg) • Cosmic Lighthouses: Discovering and characterising quasars at the edge of time

21 gennaio 2025 • Contatto: Valentina D'Odorico

Quasars at the highest redshifts illuminate the Universe during its first billion years and provide crucial insights into the formation of the earliest supermassive black holes, galaxy evolution, and the epoch of reionization. In this seminar, I will present recent advances in discovering and characterizing these distant beacons at the edge of cosmic time. I will discuss both traditional photometric selection techniques and novel machine learning approaches that are improving our ability to identify high-redshift quasar candidates in large-scale surveys. Special attention will be given to recent discoveries from the Euclid mission, which is opening new windows on the distant Universe through its unprecedented combination of survey area and depth. I will show that in 1.5 years of the Euclid mission, the high-z quasars team has doubled the number of z>7 known quasars, breaking the record twice. Following discovery, comprehensive multi-wavelength follow-up is essential to unlock the physical properties of these extreme objects. I will showcase observations spanning optical and near-infrared spectroscopy to confirm redshifts and probe the black hole masses and accretion properties, radio observations to reveal jet activity, and sub-millimeter observations to constrain the dust emission and the star formation rate in the host galaxies. This latter will be focused on a particular UV-faint Euclid-discovered quasar which we found to be hosted by a very massive and star-forming galaxy. Together, these multi-wavelength observations paint a detailed picture of the most luminous objects in the early Universe and their role in cosmic evolution.

Seminario Postdoc

14 gennaio 2025 • Contatto: Manuela Bischetti

Carina Fian (INAF-OA Trieste) • Light Echoes and Microlenses: Probing the Inner Workings of AGN

Active galactic nuclei (AGN) host some of the most compact and energetic regions in the Universe, yet their inner structure remains inaccessible to direct imaging and therefore poorly understood. In this talk, I will demonstrate how two complementary techniques — gravitational microlensing and reverberation mapping — can be used as natural microscopes to overcome this limitation and indirectly resolve the innermost regions of AGN across a wide range of physical scales. By combining time-domain information from reverberation mapping with spatial constraints from microlensing, I will show how AGN structure can be probed from the extended broad-line region (BLR), through the compact accretion disk (AD), down to the smallest scales governed by the central supermassive black hole (SMBH). Using spectroscopic and photometric monitoring data of lensed quasars and AGN from multiple facilities (including GTC, WHT, VLT, and HST), this joint approach provides robust constraints on the sizes, geometry, and kinematics of distinct emission regions and establishes a powerful framework for mapping AGN structure on sub-parsec scales. The results reveal a strongly stratified BLR, accretion disks larger than predicted by standard thin-disk theory, and new pathways toward independent SMBH mass estimates.

Christian Piscitelli (INAF-OA Trieste) • Revisiting the Early Universe: A New Spectroscopic Analysis of the z~6.4 Quasar PSO J159-02

The existence of supermassive black holes (SMBHs) with masses exceeding 10⁹ M☉ at z > 6 challenges standard theories of early black hole formation and growth. These extreme objects provide unique constraints on the properties of the first black hole seeds and the physical mechanisms driving their hyper-rapid growth. Detailed spectroscopic analysis of these objects is crucial to understand their accretion physics and the interplay with the surrounding environment.

In this talk, I present a preliminary analysis of a luminous quasar at z ~ 6.4, namely PSO J159-02, observed with the VLT/X-Shooter spectrograph. The raw 2D data were reduced using the PypeIt pipeline, including telluric correction. By modeling the rest-frame UV/optical spectrum, and using the Mg II emission line as a reliable tracer of the systemic redshift (z_MgII = 6.371) and virial mass, we estimate a BH mass of M_BH ≈ 6.6×10⁸ M☉. We find an Eddington ratio of λ_Edd ~ 0.47, suggesting the black hole is in a phase of rapid growth.

Further analysis is ongoing and includes a more detailed study of other emission lines to characterize the Broad Line Region (BLR) and an investigation into the presence of outflows, suggested by the high Eddington ratio measured, which are thought to play a key role in regulating the coevolution of the SMBH and the host galaxy.

Seminario Postdoc

17 dicembre 2025 • Contatto: 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.

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

10 dicembre 2025 • Contatto: 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.

Registrazione (in inglese)

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

4 dicembre 2025 • Seminario speciale

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.

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

3 dicembre 2025 • Contatto: 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.

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

26 novembre 2025 • Contatto: 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.

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

19 novembre 2025 • Contatto: 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 novembre 2025 • Seminario speciale

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.

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

12 novembre 2025 • Contatto: 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.

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

5 novembre 2025 • Contatto: 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.

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

29 ottobre 2025 • Contatto: 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.

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

22 ottobre 2025 • Contatto: 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.

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

15 ottobre 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.

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

8 ottobre 2025 • Contatto: 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.

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

1 ottobre 2025 • Contatto: 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.

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

26 settembre 2025 • Contatto: 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.

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

25 settembre 2025 • Contatto: 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.

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

24 settembre 2025 • Contatto: 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.

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

17 settembre 2025 • Contatto: 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.

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

10 settembre 2025 • Contatto: 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.

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