HAYDN: A Next-Generation ESA Mission Concept for Stellar Structure and Evolution and its impact on exoplanet and galaxy formation

HAYDN is one of the ten mission concepts proposed to ESA’s M-class call (M8) after its Step-1 selection. It is designed to revolutionise our understanding of stellar structure and evolution through high-precision, space-based asteroseismology in dense stellar fields, including clusters. By performing continuous photometric monitoring of stars in these dense stellar fields, HAYDN aims to map stellar interiors across a wide range of ages, masses, and chemical environments—providing unprecedented constraints on stellar physics, Galactic evolution, exoplanet’s formation, and the formation history of the Milky Way, for naming some of the HAYDN’s science cases.
In this talk, I will present the scientific motivation, mission architecture, and observational strategy of HAYDN, as well as the unique diagnostic power that seismic measurements offer for probing stellar structure in environments inaccessible to current missions. I will also give an overview of the current status of the proposal, its evolution from ESA’s M7 cycle to the ongoing M8 selection process, and the major technical milestones achieved so far.

A significant part of the talk will highlight the Spanish contribution to HAYDN, including leadership roles in mission science, coordination of key working groups, and involvement in the design of the payload and data processing pipeline. Spain is currently the second-largest contributor to the project, with active participation from several national institutes and universities.

Finally, I will outline the opportunities HAYDN opens for the Spanish community—from synergies with ground-based facilities to participation in science preparation activities—and discuss how this mission could strengthen Spain’s strategic presence in future ESA space-astrophysics programmes.

Fecha y lugar: 12/02/2026 – 12:30 | Salón de Actos
Andrés Moya Bedón
Universitat de València