Abstract
Gamma-ray bursts (GRBs) are produced by rare types of massive stellar explosion. Their rapidly fading afterglows are often bright enough at optical wavelengths that they are detectable at cosmological distances. Hitherto, the highest known redshift for a GRB was z = 6.7 (ref. 1), for GRB 080913, and for a galaxy was z = 6.96 (ref. 2). Here we report observations of GRB 090423 and the near-infrared spectroscopic measurement of its redshift, z = . This burst happened when the Universe was only about 4 per cent of its current age3. Its properties are similar to those of GRBs observed at low/intermediate redshifts, suggesting that the mechanisms and progenitors that gave rise to this burst about 600,000,000 years after the Big Bang are not markedly different from those producing GRBs about 10,000,000,000 years later.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Greiner, J. et al. GRB 080913 at redshift 6.7. Astrophys. J. 693, 1610–1620 (2009)
Iye, M. et al. A galaxy at a redshift z = 6.96. Nature 443, 186–188 (2006)
Komatsu, E. et al. Five-year Wilkinson Microwave Anisotropy Probe observations: cosmological interpretation. Astrophys. J. Suppl. Ser. 180, 330–376 (2009)
Palmer, D. M. et al. GRB 090423: Swift-BAT refined analysis. GCN Circ. 9204, (2009)
Stratta, G. & Perri, M. GRB 090423: Swift-XRT refined analysis. GCN Circ. 9212, (2009)
De Pasquale, M. & Krimm, H. GRB090423 - Swift/UVOT upper limits. GCN Circ. 9210, (2009)
Tanvir, N. et al. A γ-ray burst at a redshift of z ≈ 8.2. Nature 10.1038/nature08459 (this issue)
Thoene, C. C. et al. GRB 090423: TNG Amici spectrum. GCN Circ. 9216, (2009)
Fernández-Soto, A. et al. GRB 090423: refined TNG analysis. GCN Circ. 9222, (2009)
von Kienlin, A. GRB 090423: Fermi GBM observation. GCN Circ. 9229, (2009)
Mészáros, P. Gamma-ray bursts. Rep. Prog. Phys. 69, 2259–2322 (2006)
Zhang, B. Gamma-ray bursts in the Swift era. Chin. J. Astron. Astrophys. 7, 1–50 (2007)
Amati, L. et al. On the consistency of peculiar GRBs 060218 and 060614 with the E p,i – E iso correlation. Astron. Astrophys. 463, 913–919 (2007)
Schady, P. et al. Dust and gas in the local environments of gamma-ray bursts. Mon. Not. R. Astron. Soc. 377, 273–284 (2007)
Stratta, G. et al. Dust properties at z = 6.3 in the host galaxy of GRB 050904. Astrophys. J. 661, 9–12 (2007)
Schneider, R. et al. First stars, very massive black holes, and metals. Astrophys. J. 571, 30–39 (2002)
Springel, V. et al. Simulations of the formation, evolution and clustering of galaxies and quasars. Nature 435, 629–636 (2005)
Nagamine, K. et al. Tracing early structure formation with massive starburst galaxies and their implications for reionization. N. Astron. 50, 29–34 (2006)
Choudhury, T. R., Ferrara, A. & Gallerani, S. On the minimum mass of reionization sources. Mon. Not. R. Astron. Soc. 385, L58–L62 (2008)
Fruchter, A. S. et al. Long γ-ray bursts and core-collapse supernovae have different environments. Nature 7092, 463–468 (2006)
Lamb, D. Q. & Reichart, D. E. Gamma-ray bursts as a probe of the very high redshift universe. Astrophys. J. 536, 1–18 (2000)
Guetta, D., Piran, T. & Waxman, E. The luminosity and angular distributions of long-duration gamma-ray bursts. Astrophys. J. 619, 412–419 (2005)
Bromm, V. & Loeb, A. High-redshift gamma-ray bursts from population III progenitors. Astrophys. J. 642, 382–388 (2006)
Salvaterra, R. & Chincarini, G. The gamma-ray burst luminosity function in the light of the Swift 2 year data. Astrophys. J. 656, 49–52 (2007)
Woosley, S. E. & Bloom, J. S. The supernova gamma-ray burst connection. Annu. Rev. Astron. Astrophys. 44, 507–556 (2006)
Salvaterra, R. et al. Evidence for luminosity evolution of long gamma-ray bursts in Swift data. Mon. Not. R. Astron. Soc. 396, 299–303 (2009)
Chary, R.-R. The stellar initial mass function at the epoch of reionization. Astrophys. J. 680, 32–40 (2008)
Bolton, J. S. & Haehnelt, M. G. The observed ionization rate of the intergalactic medium and the ionizing emissivity at z ≥ 5: evidence for a photon-starved and extended epoch of reionization. Mon. Not. R. Astron. Soc. 382, 325–341 (2007)
Furlanetto, S. R. & Mesinger, A. The ionizing background at the end of reionization. Mon. Not. R. Astron. Soc. 394, 1667–1673 (2009)
Stiavelli, M. From First Light to Reionization: The End of the Dark Ages (Wiley-VCH, 2009)
Acknowledgements
We acknowledge the TNG staff for useful support during target-of-opportunity observations, in particular A. Fiorenzano, N. Sacchi and A. G. de Gurtubai Escudero. We thank A. Ferrara for discussions. This research was supported by the Agenzia Spaziale Italiana, the Ministero dell’Università e della Ricerca, the Ministero degli Affari Esteri, NASA and the US National Science Foundation.
Author Contributions Direct analysis of the Swift data: S. Campana, G. Chincarini, C.G., R.M., S.D.B., M.D.P., F.E.M., J.N., J.L.R., G. Cusumano, E.E.F., P.G., S.T.H., J.M., C.B.M., C.P., D.M.P.; analysis of the TNG and photometric data: M.D.V., S. Covino, P.D’A., A.F.-S., C.C.T., L.A.A., F.M., V.D’E., F.F., D.F., L.K.H., E. Maiorano, E. Molinari, S.M.; management of optical follow-up: P.D’A., L.A.A., V.D’E., E. Maiorano, S.M., G.A., P.F., G.L.I., N.M., E.P., S.P., G.T., V.T.; interpretation of the GRB properties: R.S., M.D.V., S. Campana, G. Chincarini, S. Covino, P.D’A., A.F.-S., C.G., R.M., C.C.T., L.A., E.P., L.S., K.H.; modelling of the GRB luminosity function: R.S., M.D.V., S. Campana, G. Chincarini, C.G., D.G., G.T. All authors made contributions through their involvement in the programmes from which the data derive, and contributed to the interpretation, content and discussion presented here.
Author information
Authors and Affiliations
Corresponding author
Supplementary information
Supplementary Information
This file contains Supplementary Data, Supplementary References and Supplementary Figures 1-6 with Legends. (PDF 628 kb)
PowerPoint slides
Rights and permissions
About this article
Cite this article
Salvaterra, R., Valle, M., Campana, S. et al. GRB 090423 at a redshift of z ≈ 8.1. Nature 461, 1258–1260 (2009). https://doi.org/10.1038/nature08445
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/nature08445
This article is cited by
The 21-cm forest as a simultaneous probe of dark matter and cosmic heating history
Nature Astronomy (2023)
Science with the 2.5-meter Wide Field Survey Telescope (WFST)
Science China Physics, Mechanics & Astronomy (2023)
Finding high-redshift gamma-ray bursts in tandem near-infrared and optical surveys
Nature Astronomy (2022)
GN-z11-flash from a man-made satellite not a gamma-ray burst at redshift 11
Nature Astronomy (2021)
Exploration of the high-redshift universe enabled by THESEUS
Experimental Astronomy (2021)
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.