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GN-z11-flash from a man-made satellite not a gamma-ray burst at redshift 11

The Original Article was published on 14 December 2020

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Fig. 1: Brightness of Breeze-M debris as a function of distance from the observer.
Fig. 2: Trajectory of Breeze-M debris in the field of view of MOSFIRE/Keck during the GN-z11-flash detection.

Data availability

The sources of all data used in this work are detailed in the Methods.

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The details of all code used in this work are provided in the Methods.


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We thank J. Baradziej, L. Jiang and C. Steinhardt for useful discussions. M.J.M. acknowledges support from the National Science Centre, Poland, through the SONATA BIS grant number 2018/30/E/ST9/00208. We acknowledge the use of the Space-Track database, JPL Horizons, OREKIT and SkyField packages. This research has made use of the Keck Observatory Archive (KOA), which is operated by the W. M. Keck Observatory and the NASA Exoplanet Science Institute (NExScI), under contract with the National Aeronautics and Space Administration.

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M.J.M. designed this project and led the writing of the manuscript. K.K. and M.K.K. searched for the satellite, calculated its properties, planned and analysed the RBT observations, made the figures and contributed to the manuscript writing. E.W. also calculated the trajectory of the satellite.

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Correspondence to Michał Jerzy Michałowski or Krzysztof Kamiński.

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The authors declare no competing interests.

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Peer review information Nature Astronomy thanks Bahram Mobasher and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Michałowski, M.J., Kamiński, K., Kamińska, M.K. et al. GN-z11-flash from a man-made satellite not a gamma-ray burst at redshift 11. Nat Astron 5, 995–997 (2021).

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