Abstract：The search for Earth-like planets around nearby stars is rapidly moving from ambition to observational reality. Over the past decade, significant progress has been driven by advances in radial velocity precision, space-based transit surveys, and high-contrast imaging, enabling the detection and initial characterization of increasingly smaller and more temperate worlds.
In this colloquium, I will focus on the current state of the search for exo-Earths in nearby stars, highlighting the key results and technical developments that define today’s discovery space. Particular emphasis will be placed on how improvements in instrumental stability, data analysis, and observational strategies have expanded sensitivity toward true Earth analogues around nearby stars.
Building on this progress, I will outline the future pathways of the field, where the emphasis shifts from detection to detailed characterization. I will discuss how upcoming facilities and coordinated multi-technique approaches will push into the regime of habitable-zone terrestrial planets and address the main limitations that still constrain the field.
Particular attention will be given to ongoing and future projects led or co-developed by the Instituto de Astrofísica de Canarias, including ultra-stable high resolution spectrographs, new-generation space mission concepts targeting low-mass stars, and the development of a near-infrared adaptive optics nulling interferometer (Small-ELF). Conceived as both a scientific instrument and a technological pathfinder, Small-ELF explores new architectures in lightweight mirrors and AI-driven adaptive optics control. Together, these efforts define a coherent roadmap toward future large-aperture systems capable of directly imaging Earth-like planets from the ground.
Bio：Prof. Rafael Rebolo is a Full Professor at the Spanish National Research Council (CSIC), a member of the Royal Academy of Sciences of Spain, and an External Professor at the Max Planck Institute for Astronomy. He served as Director General of the Institute of Astrophysics of the Canary Islands (IAC) from 2013 to 2024. His research spans observational cosmology, stellar and substellar physics, exoplanets, and astronomical instrumentation, and he is the author of over 600 scientific publications. He is a Co-Investigator for the ESA space missions Planck and Euclid, Co-Principal Investigator of the ESPRESSO ultra-stable spectrograph at the VLT (ESO), and co-discoverer of the first brown dwarfs, as well as giant and terrestrial exoplanets. PI of the CELESTE technology program. He is a recipient of the Spanish National Research Prize in Physical Sciences, the Jules Janssen Prize (France), and the Canary Islands Research Prize.
