In the optical sky, minutes-duration transients from cosmological distances are rare. Known objects that give rise to such transients include gamma-ray bursts (GRBs), the most luminous explosions in the Universe¹ that have been detected at redshifts as high as z ≈ 9.4 (refs. ^2,3,4). These high-redshift GRBs and their associated emission can be used to probe the star formation and reionization history in the era of cosmic dawn. Here, we report a near-infrared transient with an observed duration shorter than 245 s that is coincident with the luminous star-forming galaxy GN-z11 at z ≈ 11. The telluric absorption shown in the near-infrared spectrum indicates that its origin is above the Earth’s atmosphere. We can rule out the possibility of known man-made objects or moving objects in the Solar System on the basis of the observational information and our current understanding of the properties of these objects. As some long-duration GRBs are associated with a bright ultraviolet or optical flash^{5,6,7,8,9,10,11,12,13,14}, we investigate the possibility that the detected signal arose from a rest-frame ultraviolet flash associated with a long GRB from GN-z11. Despite the very low probability of being a GRB, we find that the spectrum, brightness and duration of the transient are consistent with such an interpretation. Our result may suggest that long GRBs can be produced as early as 420 million years after the Big Bang.

在光学天空中，从宇宙学距离出发的持续时间短暂的瞬变很少。即这种瞬变产生已知对象包括伽马射线暴（暴），在宇宙中最明亮的爆炸¹已经在红移高达被检测ž  ≈9.4（参考文献^2,3,4）。这些高红移GRB及其相关的发射可用于探测宇宙黎明时代的恒星形成和电离历史。在这里，我们报告了一个近红外瞬变，观测到的持续时间短于245 s，这与发光恒星形成星系GN-z11在z ≈11.近红外光谱中的碲吸收表明其起源在地球大气之上。根据观测信息和我们对这些物体的特性的当前理解，我们可以排除太阳系中已知的人造物体或运动物体的可能性。由于某些长时间的GRB与明亮的紫外线或光学闪光有关^{5,6,7,8,9,10,11,12,13,14}，我们调查了检测到的信号是否来自与来自GN-z11的长GRB相关的静止帧紫外线闪光的可能性。尽管成为GRB的可能性非常低，但我们发现瞬态的光谱，亮度和持续时间与这种解释是一致的。我们的结果可能表明，早在“大爆炸”之后的4.2亿年之内就可以生产长GRB。