Scientists of the California Institute of Technology (Caltech) They have achieved rebuild in three dimensions how explosions occur in the gas disk surrounding the supermassive black hole Located in the center of our galaxy, the Milky Way.
This milestone marks the first time that a three-dimensional recreation of the movement of gas in the vicinity of a black hole has been achieved. The team, led by the teacher Katie Boumanused neural networks and data of the ALMA radio telescope in Chile to generate a 3D model of an eruption that occurred on April 11, 2017. The reconstructed structure shows two bright, compact regions orbiting the black hole, known as Sagittarius A*at a distance of about 75 million kilometers, approximately half the distance between the Earth and the Sun.
“This is the first three-dimensional reconstruction of gas rotating near a black hole”says in a statement Bouman. Aviad Levis, a postdoctoral researcher in the group’s group and lead author of the new paper, emphasizes that while the video is not a simulation, it is also not a direct recording of the events as they took place. “It’s a reconstruction based on our black hole physics models. There’s still a lot of uncertainty associated with this because it relates to the accuracy of these models,” he says.
New computational imaging tools
To achieve this 3D reconstruction, the team had to develop novel image processing techniques that take into account phenomena such as light curvature caused by the distortion of space-time in the vicinity of objects of enormous gravity such as black holes.
Key data was provided by SOUL, which recorded a signal with a period coincident with the time it would take for a bright spot to complete an orbit around Sagittarius A*. Additionally, ALMA captures multiple single-pixel “videos” for each observation, corresponding to different polarization states of the light.
By combining this polarized light data with physical models of the emission expected in hot spots orbiting a black hole, the team was able to recover a possible 3D structure of the flare using neural networks. By computationally progressing this initial structure over time, they generated a complete light curve that matched the ALMA observations.
Sagittarius A*: The supermassive black hole of the Milky Way
Sagittarius A* (pronounced “Sagittarius A star”) is the supermassive black hole Located in the center of our galaxy, the Milky Way. With an estimated mass of about 4 million times that of the SunSgr A* exerts an enormous gravitational influence on its environment.
Despite its large mass, Sagittarius A* is surprisingly small in size, with a diameter of only about 60 million kilometers. This is due to the extreme density of black holes, in which a huge amount of matter is compressed into a very small space.
Sagittarius A* is surrounded by a disk of gas and dust that rotates around it at speeds close to the speed of light. Occasionally, some of this material falls toward the black hole, releasing enormous amounts of energy in the form of eruptions and flares.
Why is it important to study flares near black holes?
Understanding the dynamics of gas in the vicinity of supermassive black holes such as Sagittarius A* It is essential for several reasons:
- It provides us with information about the extreme physical processes that take place in these environments of extreme gravity and energy.
- It sheds light on how black holes interact with their environment and influence the evolution of their host galaxies.
- It allows you to test the predictions of Einstein’s theory of general relativity under the most demanding conditions.
Studies like this one, which combine cutting-edge observations with advanced theoretical models, bring us ever closer to unlocking the mysteries of these fascinating and enigmatic cosmic objects.
What is a supermassive black hole?
A supermassive black hole is a type of black hole with a mass millions or even billions of times greater than that of the Sun. It is believed that almost all galaxies, including our own, host one of these giants at their center.
How do gas eruptions form near black holes?
The flares occur when some of the gas from the accretion disk surrounding the black hole falls toward it. As the gas accelerates and heats up to extreme temperaturesreleases enormous amounts of energy in the form of radiation and particle jets.
What do these eruptions teach us about black holes?
Studying flares allows us to better understand the physics of accretion disks and how black holes interact with their environment. It also gives us the opportunity to test theories like general relativity in the most extreme conditions.
