PLANETES may replace the PIONIER instrument at Paranal in 2028. This project is part of the Tech-Dev programme and is financed by an ERC grant. The ERC goal is to detect exoplanets in reflected light. The Tech-Dev goals are to test new technologies — new detectors, new metrology concepts, shorter operating wavelengths — in order to accelerate the development of the next generation of VLTI instruments. We will discuss the goals and challenges of the project. In case of success, PLANETES could also be offered to the community as a new VLTI instrument.

UV attenuation tells a more complex story. Unlike IR, it is highly sensitive to line-of-sight column density, grain size distribution, and dust-stellar morphology, effects that can mimic a dust-poor galaxy even when substantial dust is present. This ambiguity sits at the heart of one of the most striking puzzles revealed by JWST: an unexpectedly large population of massive, UV-bright galaxies at z>10, the Blue Monsters, coexisting with dust-rich systems already in place by z~7, just ~300 Myr later.

I will present two recent efforts to disentangle dust physics from galaxy physics in this context. First, I show that ISM porosity driven by turbulence is key to reconciling UV and IR observations at z~7, while at z>10 additional mechanisms, grain growth or radiation-pressure-expelled dust, may be required (Sommovigo et al. 2026a). Second, I present a systematic study of attenuation curve shapes in IllustrisTNG, identifying new functional forms and galaxy properties that retain constraining power on attenuation curves regardless of dust mixture (Sommovigo et al. 2026b). Together, these results urge caution: much of the observed UV--IR tension may reflect incomplete dust modelling rather than genuinely new galaxy physics.

Polarimetry of Tidal Disruption Events

(TDEs) provides an invaluable diagnostic for the

geometry and physical mechanisms driving the

accretion flow, potentially distinguishing between

competing emission models. Recent observations

have revealed that even non-jetted TDEs can be

highly polarized (e.g. AT2020mot), raising

fundamental questions about emission mechanisms

during the early stages of accretion. While stellar

stream shocks offer an attractive interpretation, it is

not yet clear whether this is a common underlying

mechanism.I will present results from the Black hOle

Optical polarization TimE-domain Survey

(BOOTES): the first systematic optical polarization

survey of TDEs using the Nordic Optical Telescope,

the Calar Alto 2.2m telescope, the Skinakas

Observatory 1.3m telescope and the Very Large

Telescope. We find a variety of polarization

behaviors across our sample. Combined with

contemporaneous multi-wavelength data, these

trends constrain the geometry and dynamics of the

disrupted debris and the nascent accretion flow. In

particular, we report time-variable polarization

degree and position angle -an effect not previouslyadelerickerby@yahoo.com.au

reported in TDEs- pointing to more dynamic and

anisotropic systems than commonly assumed, as

well as the possible emergence of jets. Our results

showcase how polarimetric monitoring opens a new

window on the mechanisms powering supermassive-

black-hole accretion and on the earliest stages of

accretion-disk formation, and they provide testable

predictions to distinguish shock-powered and

reprocessing-dominated models.

The Extremely Large Telescope (ELT) is set to transform ground-based astronomy in the 2030s. Yet the scientific return of even the largest telescope ultimately depends on the capabilities of its instruments. The ANDES spectrograph will serve as the ELT’s high-resolution spectrograph, operating across optical and near-infrared wavelengths. Its science goals span some of the most compelling questions in modern astrophysics: detecting biosignatures in the atmospheres of rocky exoplanets, uncovering the chemical fingerprints of the first generation of stars, and testing the stability of Nature’s fundamental constants.

How do such ambitious objectives translate into a working instrument? This informal discussion will explore how cutting-edge astronomical instruments are conceived, designed, and built, and the role ESO plays in bringing them to life.

Spectroscopic surveys have been providing invaluable data in the field of Galactic archaeology and nucleosynthesis. While we are about to witness another revolution in the field with the start of 4MOST this year, we have already started to think about the next generations of spectroscopic survey facilities. In this talk, I will introduce the concept of the wide-field spectroscopic telescope (WST), which is planned for 2040s. I will discuss the need for equipping the WST with a higher spectral resolution spectrograph than the current generation of surveys, and how it can open new windows to study the origin of the elements and stellar populations in the Milky Way. 

The large amount and diversity of documentation available for users of the European Southern Observatory (ESO) — including Phase 1, Phase 2, and Phase 3 guidelines, instrument manuals, data-reduction pipeline documentation, and archive interfaces — makes it increasingly challenging for the astronomical community to efficiently find relevant information. To address this, we have developed ESOFinder, an in-house chatbot powered by Large Language Models (LLMs) and Retrieval-Augmented Generation (RAG). ESOFinder integrates public information from instrument manuals, phase 1/2/3 documentation, data reduction pipeline manuals, the ESO Knowledge Base, and key web resources to provide concise, context-aware, and reference-linked answers to user queries about proposal/observation preparation, data retrieval, and data processing. Built on open-source European LLMs (Mistral AI models), ESOFinder ensures data privacy, transparency, and complete control over the knowledge base. Its multi-step architecture allows verification of retrieved documents and generated answers, reducing the risk of hallucinations and improving the reliability of responses compared to generic tools like ChatGPT or Gemini. The current version of ESOFinder is being tested internally at ESO/DMO to evaluate its performance, assess its integration with internal workflows, and identify limitations in coverage and accuracy. These tests will guide further improvements, including the incorporation of additional documentation, and enhanced retrieval strategies. Ultimately, ESOFinder aims to become an interface for users to navigate ESO’s complex observing documentation ecosystem and to support both staff and community astronomers in their daily tasks. In this talk, I will introduce ESOFinder, describe its design—including the RAG pipeline and answer-generation strategy—and present the quality assessment of the tool based on feedback collected from ESO staff. I will finalize with a tutorial on how to use the tool so ESO staff, students, and fellows can help us test it.

Artificial Intelligence (AI) has changed our way of assessing, processing, and distributing information, and Large Language Models (LLMs) like Chat GPT, Gemini, Claude and others could be seen as a replacement of intellectual performance previously only available through human intelligence. In the scientific community, many of us have been using AI and LLMs to accelerate their scientific productivity. However, it is unclear whether LLMs are actually needed to do high-quality science or simply yield higher productivity without substantially extending knowledge? This informal discussion was triggered by a discussion I had with Jason at the ESO guest house in Chile in January. I would like to discuss whether science actually profits from LLMs or if these tools rather undermine novel, quality research by design.

Despite the century-long study of star-forming regions, we still do not have a clear observational picture of how star clusters actually assemble:
Is there a switch between hierarchical and monolithic formation? 
When do young stars decouple from their parent gas clouds? 
Current formation theories rely heavily on simulations, which often offer contrasting predictions. But with new data from multi-epoch surveys, we can finally push the boundaries of observational science and address the questions from a data-driven viewpoint.
I will briefly introduce these open questions and why they matter, and then discuss how multi-epoch NIR surveys like VISIONS, combined with new machine-learning tools, are letting us measure the motions of deeply embedded young stars and even the ISM itself. I will show what these measurements are telling us about cluster formation and how this will improve in the era of JWST, Roman, and Vera Rubin.

When governments decide whether to invest in long-term international research infrastructures such as ESO, what factors shape their decisions? Is scientific excellence sufficient? What additional returns do Member States expect?
As part of my role, I report regularly to ESO’s Member States on the national impact and benefits of membership. While scientific leadership and discovery remain integral, they represent only part of the value proposition that governments evaluate.
I will speak on the broader framework within which governments assess participation in large-scale astronomy organisations. How expectations have evolved, the role of science diplomacy in decision making, and the role of astronomers in the long-term organisational sustainability for ESO.

An Informal Discussion showcasing the analysis of Chen et al. 2025, “Who Uses Whose Telescopes? Analyzing the Knowledge Geography and Research Dominance of Global Astronomical Facilities”, sparked curiosity about the initiatives ESO has supported in Chile (its hosting country) regarding scientific and technological advancement. Since 1995, ESO has committed to supporting the development of astronomy in Chile, in the form of direct funding for research, education and training. We will show the main legal basis of the involvement of ESO in the development of astronomy in Chile, based on the “Acuerdo” for the construction of telescopes and its further modifications. Then, we will discuss the variety of astronomy initiatives supported by ESO, with an emphasis on the projects financed by the “Comite Mixto ESO-Chile", including its regional call, and the participation of Chilean students and postdocs in ESO programs.

NASA has invited the ADS team to further expand to other Earth and space science disciplines. Thus, SciX was born as a new service built on top of ADS infrastructure and databases. By serving a broader range of disciplines, SciX will also foster cross-disciplinary discovery. In this Informal Discussion, I will provide an overview of the current situation, ADS’ way forward, and present SciX. Particular emphasis will be put on how researchers can use SciX effectively with minimal changes to their established workflows.