One of the most anticipated moments for astronomers has arrived: Sagittarius A*called Sgr A* for short and known as the supermassive black hole of the Milky Way, is very close to activating.
As a report published on the website of Timesupermassive black holes are stellar objects found at the center of galaxies, whose mass can be billions of times greater than that of the Sun.
Experts working at the Chandra X-ray Observatory, the Nuclear Spectroscopic Telescope Array (NuSTAR) and the Neil Gehrels Swift Observatory (Swift) have been studying the accretion phase of the holes, which occurs when they capture an object. Sagittarius A* is about to start this process, according to The Astrophysical Journal.
How are black holes “fed”?
The accretion of a black hole begins the moment it captures something by its strong gravitational field. The process begins when angular momentum is transported and a disk, called an accretion disk, forms around the object.
The inner parts of the disk begin to spiral toward the center of the black hole and may emit a glow that can be detected by telescopes.
In the case of Sgr A*, it is in a state where it is fed very little. Its “diet” is limited to the stellar winds that orbit it, little, which is why some scientists consider it an inactive black hole. Howevera gas bubble is approaching him.
The remains of the collision of two stars
Data from the center of the Milky Way used by researchers at the University of California allowed them find a gas bubble, known as X7, which is about 50 times the mass of Earth and moves at a speed of 1,100 km/h, in an elliptical orbit around Sgr A*.
Experts propose that this gas bubble comes from the direct collision of two stars, which released remnants of gas and is now orbiting the black hole.
The astronomers’ plan is to follow the path of X7 to trace the moments before the supermassive black hole’s activation, which may give us insight into the gravitational pull of the central object and how it affects its environment. Also, understanding the gas bubble can give us answers about the physics of accretion.