A Cosmic Miracle: A Remarkably Luminous Galaxy at z=14.44 Confirmed with JWST

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Astrophysics of Galaxies

Pascal A. Oesch

Gabriel Brammer

Andrea Weibel

Yijia Li

Jorryt Matthee

John Chisolm

Clara L. Pollock

Kasper E. Heintz

Benjamin D. Johnson

Xuejian Shan

Raphael E. Hviding

Joel Leja

Sandro Tacchella

Arpita Ganguly

Callum Witten

Hakim Atek

Siro Belli

Sownak Bose

Rychard Bouwens

Pratika Dayal

Roberto Decarli

Anna de Graaff

Yoshinobu Fudamoto

Emma Giovinazzo

Jenny E. Greene

Garth Illingworth

Akio K. Inoue

Sarah G. Kane

Ivo Labbe

Ecaterina Leonova

Rui Marques-Chaves

Roman A. Meyer

Erica J. Nelson

Guido Roberts-Borsani

Daniel Schaerer

Robert A. Simcoe

Mauro Stefanon

Yuma Sugahara

Sune Toft

Arjen van der Wel

Pieter van Dokkum

Fabian Walter

Darrach Watson

John R. Weaver

Katherine E. Whitaker

ccby-4.0

Naidu, Rohan P., Pascal A. Oesch, Gabriel Brammer, Andrea Weibel, Yijia Li, Jorryt Matthee, John Chisolm, et al. 2026. “A Cosmic Miracle: A Remarkably Luminous Galaxy at  zspec = 14.44 Confirmed with JWST.” The Open Journal of Astrophysics 9 (January). https:/​/​doi.org/​10.33232/​001c.156033.

Abstract

JWST has revealed a stunning population of bright galaxies at surprisingly early epochs, z>10, where few such sources were expected. Here we present the most distant example of this class yet – MoM-z14, a luminous (MUV=20.2) source in the COSMOS legacy field at zspec=14.44+0.020.02 that expands the observational frontier to a mere 280 million years after the Big Bang. The redshift is confirmed with NIRSpec/prism spectroscopy through a sharp Lyman-α break and 3σ detections of five rest-UV emission lines. The number density of bright zspec1415 sources implied by our “Mirage or Miracle” survey spanning 350 arcmin(2 is >100× larger (182+329105×) than pre-JWST consensus models. The high EWs of UV lines (1535\AA) signal a rising star-formation history, with a 10× increase in the last 5 Myr (SFR5Myr/SFR50Myr=9.9+3.05.8). The source is extremely compact (circularized re=74+1512 pc), and yet elongated (b/a=0.25+0.110.06), suggesting an AGN is not the dominant source of UV light. The steep UV slope (β=2.5+0.20.2) implies negligible dust attenuation and a young stellar population. The absence of a strong damping wing provides tentative evidence that the immediate surroundings of MoM-z14 may be partially ionized at a redshift where virtually every reionization model predicts a 100% neutral fraction. The nitrogen emission and highly super-solar [N/C]>1 hint at an abundance pattern similar to local globular clusters that may have once hosted luminous supermassive stars. Since this abundance pattern is also common among the most ancient stars born in the Milky Way, we may be directly witnessing the formation of such stars in dense clusters, connecting galaxy evolution across the entire sweep of cosmic time.