A dark spot darker than nothing, a cosmic gap that can swallow everything: the astronomical community around the world is celebrating a historic development on Thursday, the first direct observation of the black hole at the center of the galaxy./p>
The stunning portrait comes from the Event Horizon Telescope (ETH), a global network of antennas that act as a single, giant radio telescope. It takes its name from the event horizon, the imaginary sphere around a black hole through which nothing, not even light, can escape.
The spectacular picture was presented Thursday with simultaneous press conferences in six countries, an unusual practice that reflects the importance of the study.
About 300 astronomers from around the world present the findings in a special issue of the Astrophysical Journal Letters./p>
The historic portrait of the black hole in the center of our Galaxy. Light comes from superheated material moving around it (EHT Collaboration)
Most, if not all, galaxies have black holes at their center that are millions or even billions of times larger than the Sun – much heavier than other black holes formed by the collapse of dying stars. Central black holes are thought to form early in the evolution of galaxies and grow larger and larger over time.
The black hole in Milky Way's heart, which is 4 million times the mass of the Sun, is located in the direction of the constellation Sagittarius, 26,000 light-years from Earth, and is called Sagittarius A * or SgrA *.
The center of the galaxy as seen from the sky of the southern hemisphere in Chile (ESO)
Until now, its presence could only be perceived by the movement of stars in the center of the galaxy, which can be seen orbiting an empty spot at unimaginable speed.
The image presented on Thursday shows the silhouette, or shadow, of the black hole, with the background of the glow of the superheated gas that the monster spins before it is lost inside it forever.
Sagittarius A *'s portrait is just the second direct observation of a black hole. The beginning was made in 2019 with the black hole in the center of the neighboring galaxy Messier 87. It is located far away from SgrA *, about 54 million light-years from Earth, but its mass is larger, about 6.5 billion times larger than the Sun.
The 2019 study confirmed, among other things, a prediction based on the theory of relativity, according to which the silhouette of a black hole is almost a perfect circle.
