A Cosmic Miracle: A Remarkably Luminous Galaxy at _z_ spec = 14.44 Confirmed with JWST
| Title: | A Cosmic Miracle: A Remarkably Luminous Galaxy at _z_ spec = 14.44 Confirmed with JWST |
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| Authors: | Rohan P. Naidu; 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; Sirio 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 |
| Source: | The Open Journal of Astrophysics, Vol 9 (2026) |
| Publisher Information: | Maynooth Academic Publishing |
| Publication Year: | 2026 |
| Collection: | Directory of Open Access Journals: DOAJ Articles |
| Subject Terms: | Astronomy; QB1-991; Astrophysics; QB460-466 |
| Description: | 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 ($M_{\rm{UV}}=-20.2$) source in the COSMOS legacy field at $z_{\rm{spec}}=14.44^{+0.02}_{-0.02}$ 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-$\alpha$ break and $\approx3\sigma$ detections of five rest-UV emission lines. The number density of bright $z_{\rm{spec}}\approx14-15$ sources implied by our "Mirage or Miracle" survey spanning $\approx350$ arcmin${\mathstrut}^{2}$ is $>100\times$ larger ($182^{+329}_{-105}\times$) than pre-JWST consensus models. The high EWs of UV lines (${\approx}15{-}35$\AA) signal a rising star-formation history, with a ${\approx}10\times$ increase in the last 5 Myr ($\rm{SFR_{\rm{5Myr}}}/\rm{SFR_{\rm{50Myr}}}=9.9^{+3.0}_{-5.8}$). The source is extremely compact (circularized $r_{\rm{e}} = 74^{+15}_{-12}$ pc), and yet elongated ($b/a=0.25^{+0.11}_{-0.06}$), suggesting an AGN is not the dominant source of UV light. The steep UV slope ($\beta=-2.5^{+0.2}_{-0.2}$) 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 $\approx100\%$ 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. |
| Document Type: | article in journal/newspaper |
| Language: | English |
| Relation: | https://doi.org/10.33232/001c.156033; https://doaj.org/toc/2565-6120; https://doaj.org/article/1334a39355284921b3e4bb1b3d1c35b3 |
| DOI: | 10.33232/001c.156033 |
| Availability: | https://doi.org/10.33232/001c.156033; https://doaj.org/article/1334a39355284921b3e4bb1b3d1c35b3 |
| Accession Number: | edsbas.68C751E5 |
| Database: | BASE |