The colossal black hole lurking in the middle of the Milky Way runs almost as fast as the maximum rotation speed.
That is just one thing that astrophysicists have discovered after developing and applying a new method to tease the secrets that are still hidden in super -massive observations with black holes collected by the Horizon Telescope (EHT) event.
The unprecedented worldwide cooperation has worked for years to give us the first direct images of the shadows of black holes, first with M87* in a Milky Way Lighting of 55 million light years, then with SGR A*, the super -massive black hole in the heart of our own Milky Way.
These images are incredible – but also difficult to interpret. So to find out what we are looking at, scientists turn to simulations. They build a number of virtual characteristics and find out which of them most resemble the observation data. This technique is widely used with the EHT images, but now it has merged a notch.
A team led by astronomer Michael Janssen from Radboud University in the Netherlands and the Max Planck Institute for Radio Astronomy used in Germany High-Throughput Computing to develop millions of simulated black holes.
They then used that data to train a neural network to remove as much information as possible from the data and to identify the properties of the black holes.
Their results show, among other things, that SGR A* is not only running in the maximum speed, but that its rotation axis is pointed in the direction of the earth and that the glow around it is generated by hot electrons.
Perhaps the most interesting thing is that the magnetic field in the material around SGR a* does not seem to behave in a way predicted by theory.
M87*, they discovered, also rotates quickly, although not as fast as SGR a*. However, it rotates in the opposite direction of the material that swirls in a disc around it – possibly due to a merger from the past with another super -massive black hole.
“That we defy the prevailing theory is of course exciting,” says Janssen.
“However, I see our AI and Machine Learning approach mainly as a first step. Then we will improve and expand the corresponding models and simulations. And when the Africa Millimeter Telescope, which is under construction, participates in collecting data, we will get even better information to validate the general theory of precision with a high -mass.”
The team has detailed their methodology and findings in three articles published in Astronomy and astrophysics. They can be found here, here and here.
