The Event Horizon Telescope (EHT) Collaboration – including the group led by FIAS Fellow Luciano Rezzolla - has released new images of M87*, the supermassive black hole at the center of the galaxy Messier 87. They confirm predictions of the general theory of relativity.
The newly calculated images are based on observations in April 2018 and show a ring surrounding the "shadow of the black hole", as in the first image of M87* from 2017. The maximum brightness of this ring has shifted by about 30º compared to the 2017 image. This had also been predicted theoretically, as the ring is made of material swirling around the black hole.
Luciano Rezzolla, EHT executive board member, professor at Goethe University Frankfurt and FIAS Senior Fellow, emphasizes: “All predictions for the appearance of the black hole M87* that we made on the basis of Albert Einstein’s general theory of relativity can be confirmed with the second image of M87*. The brightness peak of the ring is also in the ‘right’ place, because we are looking at the emission from turbulent material in the accretion disk around this black hole at a certain inclination.” This second image of M87* may not seem very spectacular to the public, says the theoretical physicist whose Frankfurt team provided essential contributions to the theoretical modelling of the data: “However, for science, it is an extremely important confirmation. While the excitement in science obviously comes with the discovery, the confidence in science comes from the confirmation of previous results. Hence, the new image testifies that the analysis behind first image of a black hole was indeed correct and accurate.”
In 2017, the EHT took the first image of a black hole. This object, M87*, is the beating heart of the giant elliptical galaxy Messier 87 and lives 55 million light years away from Earth. The image of the black hole revealed a bright circular ring, brighter in the southern part of the ring. Further analysis of the data also revealed the structure of M87* in polarized light, giving us greater insight into the geometry of the magnetic field and the nature of the plasma around the black hole.
In addition to 2017 and 2018, the EHT collaboration also carried out successful observations in 2021 and 2022 and is expected to start another measurement campaign in the first half of 2024.
Publication: Event Horizon Telescope Collaboration. The persistent shadow of the supermassive black hole of M 87. I. Observations, calibration, imaging, and analysis. Astronomy & Astrophysics, 18th January 2024, https://doi.org/10.1051/0004-6361/202347932