![]() 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 tell-tale 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, produced by the Event Horizon Telescope (EHT) Collaboration, uses observations from a worldwide network of radio telescopes, and is a long-anticipated look at the massive object that sits at the very centre of our galaxy. The result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the workings of such giants, which are thought to reside at the centre of most galaxies. So-called supermassive black holes, such as the one sitting at the center of the Milky Way and most galaxies, are at least a million times bigger than the Sun.The first image of the supermassive black hole at the centre of our own Milky Way galaxy has been produced by a global team involving UCL researcher Dr Ziri Younsi. These can be up to 20 times more massive than the Sun but are tiny in space. The first form when the center of a very big star collapses in on itself, creating a supernova. The EHT is not a single instrument but a network of eight radio telescopes spanning the globe in order to create a virtual, Earth-sized telescope.Įven then, locking in an image of M87's supermassive black hole is comparable to photographing a pebble on the Moon. Of the competing theoretical models, only those assuming strongly magnetized gas are consistent with these new observations, the researchers said. The groundbreaking image of M87's black hole and its shadow in polarized light allows astronomers to see for the first time this interplay between matter flowing in and being ejected. Most matter lying close to the edge of a black hole falls in, but some particles escape moments before capture and are blown far out into space. ![]() The bright jets of energy and matter that extend some 5,000 lightyears from M87's core are one of the galaxy's great mysteries. They are most often detected by the radiation produced when their gravity pulls in surrounding gases, a process called accretion. At the same scale of compression, Earth would fit inside a thimble. Matter in a black hole is so dense as to create a gravity field from which even light cannot escape. This makes it possible to map the magnetic field lines at the black hole's inner edge. In the same way that specially treated sunglasses reduce reflections and glare from bright surfaces, astronomers can see the regions around a black hole better by looking at how the light is polarised.
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