Year: 2026
Type: article
Abstract: Galaxy distances are central to our understanding of the Universe. Despite the success of existing approaches, independent and complementary methods remain valuable for testing systematic effects and extending the applicability range of different distance metrics. Here we demonstrate that the spectrum of an individual semiresolved stellar population encodes direct information about its distance and that valuable distance constraints can, in principle, be obtained by combining multiple independent measurements. When applied to optical spectra of bulge of the Andromeda galaxy (M31), we derive a stellar population–based distance of 756 ± 57 kpc ( μ 0 = 24.39 ± 0.15), in agreement with state-of-the-art measurements. Crucially, semiresolved stellar population distances do not require secondary calibrations, although its absolute scale remains conditional on the adopted stellar population models. Our findings provide a first assessment of the feasibility of deriving stellar population–based distance estimates from simple stellar population models, motivating further tests of the broader applicability and precision of the method.
Authors: Ignacio Martín-Navarro, Patricia Iglesias Navarro, Francesco La Barbera, Alexandre Vazdekis, Michael A. Beasley, ChangHoon Hahn, Luis Peralta de Arriba, Isaac Alonso Asensio, Eirini Angeloudi, Miguel Cerviño, Katja Fahrion, Tereza Jerabkova, Jesús Falcón-Barroso, Sebastián F. Sánchez, Prashin Jethwa
Institutions: Universidad de La Laguna, Instituto de Astrofísica de Canarias, Astronomical Observatory of Capodimonte, National Institute for Astrophysics, Swinburne University of Technology, University of Arizona, Universidad Nacional de Educación a Distancia, University of Vienna, Masaryk University, Universidad Nacional Autónoma de México
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,400
OpenAlex ID: W7171501779