It is a historic result! Three years after publishing the very first image of a supermassive black hole, the one located in the heart of the Messier 87 galaxy in the constellation of Virgo, the scientific collaboration of the Event Horizon Telescope – which has no less than 300 researchers from 80 institutes around the world – has just unveiled the very first image of Sagittarius A* (Sgr A*), the colossal star that hides about 27,000 light years from Earth in the center of our Milky Way.
A unique snapshot which shows that it is indeed, as supposed, a black hole four million times more massive than our sun. A celestial object so compact that the intense gravitational pull it exerts prevents even light from escaping from it.
Exceptional shooting
But then how was it possible to photograph it? Although the black hole itself is invisible, the incandescent gas it sucks in and which wraps around it until it engulfs it reveals it negatively as a dark central region surrounded by a shiny structure in the form of a ring.
To achieve this exceptional shot, the astronomers used eight radio telescopes existing across the planet, in a network, as if they formed a single observatory: the Event Horizon Telescop (EHT). As for the necessary observations, they took place over several nights for several hours, like a photographer using a long pause time.