The galaxy M87 is one of the prime targets for high resolution radio imaging to investigate the ring-like “shadow” of its supermassive black hole, the innermost regions of accretion flow, and the formation of the relativistic jet. In 2018, observations with the Global mm-VLBI array (GMVA) including the Effelsberg 100-m telescope and with the Atacama Large Millimetre Array (ALMA) at 86 GHz enabled the simultaneous reconstruction of a ring structure and the extended jet emission. Jong-Seo Kim and a number of additional scientists, predominantly from the Max Planck Institute for Radio Astronomy, revisited the GMVA observations in 2018 using novel imaging algorithms. This work confirms the ring and jet detection at 86GHz and provides higher resolution images with more precise measurement of the ring and jet features (2025, A&A, 696, A169).
more