The EHT Event Horizon Telescope scientific collaboration, which had released the first "photo" of a black hole in 2019, has released new images of M87, the supermassive black hole at the center of the Messier 87 galaxy: this time the images were made from data from observations made in April 2018, a year later than the data that led to the image released in 2019. Thanks to the participation of a new telescope, the Greenland Telescope, and a dramatically improved data acquisition rate at all telescopes in the EHT network, the 2018 observations give us a view of the source independent of the first observations in 2017. The new images were made by an international research team from the EHT collaboration, which includes researchers from the National Institute of Astrophysics (INAF), the National Institute of Nuclear Physics (INFN), the University of Naples Federico II and the University of Cagliari, and were recently published in the journal Astronomy & Astrophysics. The images reveal a bright ring, the same size as the one observed in 2017, surrounding a deep central depression, "the shadow of the black hole”, as predicted by general relativity. What differs is the position of the ring's brightness peak, which has shifted about 30 degrees from the 2017 images. This is consistent with our theoretical understanding of the variability of turbulent material around black holes. "The confirmation of the ring in a completely new data set is a huge milestone for our collaboration and a strong indication that we are observing the shadow of a black hole and the material orbiting around it," says Keiichi Asada, a researcher at the Academia Sinica Institute for Astronomy and Astrophysics in Taiwan and coordinator of the working group that authored the paper published in Astronomy & Astrophysics.
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