The James Webb Space Telescope (JWST) has identified galaxies at redshift z = 13, and many luminous galaxies at z > 10, suggesting rapid galaxy development. However, spectroscopic confirmation is often lacking. This paper presents JWST NIRSpec spectroscopic confirmation of two luminous galaxies at z = 14.32⁺⁰·⁰⁸ and z = 13.90 ± 0.17, showing ultraviolet continua with Lyman-α breaks but no emission lines. This proves luminous galaxies existed 300 million years after the Big Bang and are more common than previously expected. The most distant galaxy is unexpectedly luminous and spatially resolved, indicating stellar continuum emission dominance, challenging models that attribute luminosity solely to black hole accretion.

Stefano Carniani, Kevin Hainline, Francesco D'Eugenio, Daniel J. Eisenstein, Peter Jakobsen, Joris Witstok, Benjamin D. Johnson, Jacopo Chevallard, Roberto Maiolino, Jakob M. Helton, Chris Willott, Brant Robertson, Stacey Alberts, Santiago Arribas, William M. Baker, Rachana Bhatawdekar, Kristan Boyett, Andrew J. Bunker, Alex J. Cameron, Phillip A. Cargile, Stéphane Charlot, Mirko Curti, Emma Curtis-Lake, Eiichi Egami, Giovanna Giardino, Kate Isaak, Zhiyuan Ji, Gareth C. Jones, Nimisha Kumari, Michael V. Maseda, Eleonora Parlanti, Pablo G. Pérez-González, Tim Rawle, George Rieke, Marcia Rieke, Bruno Rodríguez Del Pino, Aayush Saxena, Jan Scholtz, Renske Smit, Fengwu Sun, Sandro Tacchella, Hannah Übler, Giacomo Venturi, Christina C. Williams, Christopher N. A. Willmer