The breakthrough follows the EHT collaboration’s 2019 release of the first image of a black hole, called M87*, at the centre of the more distant Messier 87 galaxy. The EHT observed Sgr A* on multiple nights, collecting data for many hours in a row, similar to using a long exposure time on a camera. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single ‘Earth-sized’ virtual telescope. ‘These unprecedented observations have greatly improved our understanding of what happens at the very centre of our galaxy, and offer new insights on how these giant black holes interact with their surroundings.’ Doughnut on the moonīecause the black hole is about 27,000 light-years away from Earth, it appears to us to have about the same size in the sky as a doughnut on the Moon. ‘We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity,’ said EHT Project Scientist Geoffrey Bower from the Institute of Astronomy and Astrophysics, Academia Sinica, Taipei. The first picture of Sagittarius A* (Credits EHT) The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun. This strongly suggested that this object – known as Sagittarius A* (Sgr A*, pronounced ‘sadge-ay-star’) – is a black hole, and today’s image provides the first direct visual evidence of it.Īlthough we cannot see the black hole itself because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a ‘shadow’) surrounded by a bright ring-like structure.
Scientists had previously seen stars orbiting around something invisible, compact, and very massive at the centre of the Milky Way. The image is a long-anticipated look at the massive object that sits at the very centre of our galaxy. The results are being published today in a special issue of The Astrophysical Journal Letters. In the Netherlands, astronomers and technicians from the University of Amsterdam, Radboud University, Leiden University, the University of Groningen, JIVE and ASTRON are part of the EHT collaboration. The team has made use of observations from a global network of radio telescopes. ‘We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity' ‘But today we’re publishing the best picture ever!’ ‘I’ve been looking at Sagittarius A* since my PhD research in Leiden and it’s always been difficult because of everything that’s between us and the centre of the Milky Way,’ says Van Langevelde. He presented the results today at a press conference at the headquarters of the European Southern Observatory (ESO) in Garching, Germany. Leiden Professor of Galactic Radio Astronomy Huib Jan van Langevelde is the director of this global collaboration, the Event Horizon Telescope (EHT).
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