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Finding Earth-like exoplanets using high-precision radial-velocity measurements requires more than an exceptionally stable spectrograph. It also requires software to turn scientific objectives into observations, coordinate those observations with the telescope, capture the resulting engineering and scientific data, and make that data accessible to researchers.

The Terra Hunting Experiment and Open-Time Observations on the Isaac Newton Telescope (INT) use HARPS3, a high-resolution, high-stability echelle spectrograph designed for precise radial-velocity measurements. Since 2019, I have worked on the software infrastructure supporting these programmes.

This talk will follow the journey from an astronomer requesting observations to those observations becoming scientific data. It will focus particularly on the Python-based Scheduler, which selects the most appropriate target to observe at a given time by considering factors including target coordinates, visibility, telescope constraints and observing conditions. The talk will also cover the Phase 2 web application used by astronomers to prepare observations, the Engineering Database that captures data published by the telescope and instruments, and the Data Archive that will provide long-term storage and access to observations and calibrations.

Using HARPS3 as a case study, the talk will explore the challenges of developing software at the boundary between scientific requirements, astronomical instrumentation and autonomous telescope operations, and the role that robust, maintainable software plays in making a complex observing programme possible.

Mr Ian Wellaway

University of Exeter, UK

Mr Ian Wellaway

University of Exeter, UK

Ian Wellaway is a Research Software Engineer at the University of Exeter with more than 25 years' experience developing research software and digital infrastructure. Since 2019, he has worked on the Terra Hunting Experiment, developing software systems that support the HARPS3 high resolution echelle spectrograph installed at the Isaac Newton Telescope and used in the search for Earth-like exoplanets.

His work spans the software that enables astronomical observations, including the Python-based scheduler that selects optimal targets based on telescope constraints, target visibility and observing conditions. He has also developed the Phase 2 web application used by astronomers to prepare observations, the engineering database for collecting telemetry from telescope systems, and the science data archive that stores and distributes observations and calibration data to the collaboration.

Ian works closely with astronomers and engineers across the Terra Hunting Experiment and the Isaac Newton Group of Telescopes to develop reliable, maintainable software that supports the operation and long-term sustainability of modern astronomical instrumentation.

The flow of data produced by a network of stabilized spectrographs operating regularly around the globe and around the clock is something the EPRV community has yet to fully grapple with. Standardisation of observing methods, data products, and reduction and analysis pipelines will be essential for meaningful comparisons between observations from different facilities. But equally important will be the creation of effective communication channels between the many nodes of such a project, ensuring that insights from any one area can be shared and leveraged to improve overall RV precision and performance.

In this talk, I will use lessons learned from NASA’s EPRV Research Coordination Network and the EPRV Data Standard team to consider what’s needed to turn a collection of instruments into a functioning global network: How should observations and data products be coordinated across facilities? How can calibration information, pipeline improvements, and stellar-activity diagnostics be shared across the network? How should standards and analysis methods evolve as the field develops? And, most importantly, how can lessons learned within one node of the project benefit the entire network?

These questions will frame a discussion on the broader observing, analysis and communication infrastructure that must be developed alongside the instruments themselves, with the goal of identifying and prioritising gaps that the EPRV community should begin addressing well before any data start arriving.

Dr Jennifer Burt

NASA Jet Propulsion Laboratory, US

Dr Jennifer Burt

NASA Jet Propulsion Laboratory, US

Jennifer Burt is the Extreme Precision Radial Velocity (EPRV) discipline scientist within NASA’s Exoplanet Exploration Program Office. She leads the agency’s EPRV Research Coordination Network which aims to increase communication and collaboration within the global EPRV community. Her research focuses on the RV detection and confirmation of low-mass planets both via traditional uninformed surveys and by following up transiting planet candidates from NASA’s TESS mission. Dr Burt is the lead of a new, community-informed, EPRV data format which lays the groundwork for a coordinated comparison of spectroscopic data between modern EPRV instruments and reduces the need for new instruments to independently develop a data standard and pipeline. She also investigates best practices for EPRV survey scheduling and has led studies on the optimal distribution of telescope apertures, locations, and RV capabilities for the detection of Earth analog planets.

Tiny RV signals, such as those of Earth twins, require large and precise dataset to be detected. Combining data from different spectrographs allows us to share the load on the telescope time, increase detection robustness and the accuracy of the inferred parameters. For instance, joining visible and NIR spectrographs helps, in some cases, to disentangle planetary signals from stellar activity. In this talk, I will briefly review the main results combining SOPHIE and SPIRou RVs. I will then focus on the lessons we learned from a decade of observing the HIP41378 multi-planetary system with various instruments, including the international campaign during the 2022’s transit of planet f. The latter involved most EPRV spectrographs in the world, on the same target and the same night. In will conclude this talk by outlining some recommendations for a spectrograph network hunting for Earth twins.

Dr Alexandre Santerne

Laboratoire d'Astrophysique de Marseille, France

Dr Alexandre Santerne

Laboratoire d'Astrophysique de Marseille, France

Alexandre Santerne is a radial velocity expert with a speciality in the follow-up of transiting exoplanets. After a PhD thesis working for the CoRoT space mission, he explores the planet candidates from the Kepler, then K2 mission, focusing on giant planet at long orbital period. Over the last decade, he led the monitoring the HIP41378 system with instruments like HARPS, HARPS-N and ESPRESSO. This is a fascinating system which host 6 or maybe 7 low-mass planets, most of them transiting at long period. The characterisation of this system goes beyond planetary masses but also include the Rossiter-McLaughlin effect of a planet with a 19-h long transit duration which required a worldwide campaign with all available extreme-precision radial-velocity spectrographs.

The incredible, hard-earned advancements in (E)PRV instrumentation means we now have the opportunity to compare instrument performance across optical designs with real data. I will share lessons learned from comparing contemporaneous Sun-as-a-star data across different instruments. This analysis reveals both (1) different instrument systematics across varied design principles, and (2) complications of combining data with differing properties in a precision RV context. I will additionally demonstrate the promise of using hierarchical wavelength calibration (eg excalibur) to trace current instrumental variations and thereby generate informed future instrument design.

Dr Lily Zhao

University of Chicago, US

Dr Lily Zhao

University of Chicago, US

Lily Ling Zhao is a NASA Sagan Fellow at the University of Chicago and the project scientist for EXPRES, an ultra-stabilized optical spectrograph. Zhao founded and now co-leads the Extreme Stellar Signals Project, a community-wide collaboration with over 40 members working to mitigate stellar signals (now the largest source of scatter in precision radial velocity measurements). Zhao also lead the development of excalibur, a hierarchical method for wavelength calibration that parameterises how different spectrographs vary.

PLATO is the European Space Agency’s next medium-class mission, due for launch in March 2027. Its key science goals are to discover transiting exoplanets, including Earth analogues, via the transit method, to characterise their host stars using asteroseismology, and crucially to measure the planets’ masses using ground-based radial velocity follow-up. In my talk I will briefly introduce the mission, outline its expected exoplanet sensitivity and yield, which have been assessed using detailed simulations, and discuss the challenges of measuring the masses of the planet candidates PLATO will find. In particular, I will set out the requirements of PLATO’s ground-based observing programme in terms of telescope time, and compare those to existing facilities.

Professor Suzanne Aigrain

University of Oxford, UK

Professor Suzanne Aigrain

University of Oxford, UK

Suzanne Aigrain is Professor of Astrophysics at the University of Oxford and a Fellow of All Souls College. Her research focuses on the detection and characterisation of exoplanets using the transit and radial velocity methods, and on modelling and mitigating the intrinsic variability of their host stars. She co-chairs the PLATO Stellar Variability mitigation Working Group, and chairs the Terra Hunting Experiment Science Team. She is also one of the science leads for the Planethunters-TESS citizen science project. In 2026 she was awarded the Royal Astronomical Society’s George Darwin Lectureship for her contributions to Astrophysics and scientific public outreach

As of September 2026, astronomers have detected over 6000 planets orbiting other stars. These planets exhibit remarkable diversity and include worlds that are strikingly different from those in the solar system. However, due to the small amplitudes and long timescales of signals induced by planets like those in the solar system, our knowledge of other planetary systems with solar-system-like architectures is still incomplete. More generally, due to detection biases, the majority of detected exoplanets have extremely short orbital periods and are therefore much more irradiated than similarly massive worlds in the solar system. Focusing on the population of stars within 20 pc of the Sun, I will present the census of nearby exoplanets and discuss how various radial velocity surveys led to the detection of over 80% of these planets. I will then determine the aggregate search completeness of multiple planet searches to assess the number and properties of the substantial population of not-yet-discovered planets that could be orbiting the closest stars. I will conclude by considering possible observational strategies and the importance of new instrumentation for detecting those planets and thereby improving our understanding of planetary demographics.

Dr Courtney Dressing

University of California, Berkeley, US

Dr Courtney Dressing

University of California, Berkeley, US

Courtney Dressing is an observational astronomer focused on detecting and characterising planetary systems orbiting nearby stars. She is an associate professor in the Department of Astronomy at the University of California, Berkeley, where she holds the Watson and Marilyn Alberts Chair in the Search for Extraterrestrial Intelligence (SETI). She has been involved in several NASA missions and has contributed to planning future missions including the upcoming Habitable Worlds Observatory. In recognition of her work, Courtney has been awarded the Alfred P. Sloan Research Fellowship, the David & Lucile Packard Fellowship, and the Newton Lacy Pierce Prize. Courtney received a PhD and AM in astronomy and astrophysics from Harvard University and an AB in astrophysical sciences from Princeton University.

The search for life beyond the Solar System has emerged as one of the defining scientific endeavours of our era. While thousands of exoplanets have been discovered, identifying biospheres on distant worlds requires measuring atmospheric biosignatures - chemical species maintained out of equilibrium by biological activity. However, existing and upcoming observatories lack the sensitivity needed to directly image and spectrally analyse a statistically significant sample of nearby temperate, terrestrial planets.

The Large Interferometer for Exoplanets (LIFE) mission addresses this challenge. LIFE is proposed as a space-based mid-infrared nulling interferometer consisting of a formation-flying constellation of telescopes. By operating in the mid-infrared spectral range, LIFE will detect the intrinsic thermal emission of temperate Earth-sized exoplanets while suppressing the glare of their host stars. This will enable the direct detection and atmospheric characterisation of dozens of terrestrial worlds, searching for key gases such as water vapor, carbon dioxide, ozone, and methane.

In this talk, I will present the rationale behind LIFE, review its scientific capabilities, and outline the technology maturation and development strategy - including ongoing laboratory experiments at ETH Zurich like the Nulling Interferometry Cryogenic Experiment (NICE) - that paves the way toward an international flagship mission.

Professor Sascha Quanz

ETH Zürich

Professor Sascha Quanz

ETH Zürich

Sascha P Quanz is a Full Professor of Astrophysics at ETH Zurich, where he leads the Exoplanets and Habitability Group. He studied physics at Heidelberg University and earned his PhD from the Max Planck Institute for Astronomy. A driving force in space research, Quanz played a key role in setting up ETH Zurich | Space to advance space science and engineering across the university. He also co-founded ETH’s interdisciplinary Centre for Origin and Prevalence of Life (COPL) and served as its inaugural Deputy Director. Additionally, Quanz serves as Principal Investigator and Executive Director leading the LIFE (Large Interferometer for Exoplanets) mission. This program aims to develop, deploy, and operate a space-based mid-infrared interferometer to directly image Earth-like exoplanets and analyse their atmospheres for traces of life.