The first image of a black hole shadow graced the front pages of newspapers around the world when it was released by the Event Horizon Telescope (EHT) collaboration in 2019. Here the EHT team follows on from that groundbreaking result, presenting re-imaging of the same supermassive black hole M87* using data from the subsequent observing run, in April 2018.

Significant improvements have been made since the initial observations, and this second run benefitted from increased bandwidth and a wider frequency coverage in part due to the addition of the Greenland Telescope to the network. The new data enable confirmation of the size and shape of the asymmetric ring-like structure observed previously, with a consistent diameter of ~42 μas across both runs. However, a significant change is seen in the position angle of the bright spot in the ring, which shifted by about 30° relative to the earlier result.

事件视界望远镜 (EHT) 合作组织于 2019 年发布了第一张黑洞阴影图像，该图像登上了世界各地报纸的头版。EHT 团队在此基础上延续了这一突破性结果，展示了黑洞阴影的重新成像。使用 2018 年 4 月后续观测运行的数据对同一超大质量黑洞 M87* 进行了观测。

自初次观测以来，已经取得了重大改进，第二次运行受益于带宽的增加和频率覆盖范围的扩大，部分原因是网络中增加了格陵兰望远镜。新数据能够确认之前观察到的不对称环状结构的尺寸和形状，两次运行的直径一致为约 42 μas。然而，环中亮点的位置角度发生了显着变化，相对于之前的结果偏移了约30°。