Black holes are one of the most fascinating objects of astrophysics. They have captivated scientists and the general public since the eighteenth century without ever providing tangible proof of their existence. For a simple reason: they could never be observed. According to Einstein’s theory of general relativity, which theorizes how they work, these galactic monsters exert such gravitational attraction that they swallow any matter that approaches it a little too tightly and let nothing escape, not even the light. They are therefore invisible.
The only representations humanity has so far are numerical simulations based on scientific theories. The EHT project has combined eight telescopes across the globe to create a virtual telescope of about 10,000 km in diameter, almost the size of the Earth. They targeted in April 2017 two supermassive black holes to try to get an image. The researchers sought to identify the immediate boundary of a black hole, the horizon of events, where the material emits light when absorbed by the black hole. The result of these observations is to be released today.