Magnetic fields form spiral around black hole – 03/27/2024 – Science

Astronomers have discovered powerful magnetic fields that spiral around the supermassive black hole Sagittarius A*, located at the heart of the Milky Way. The European Southern Observatory (ESO) made the announcement this Wednesday (27).

Produced in collaboration with the Event Horizon Telescope (EHT), the polarized light image reveals a structure surprisingly similar to that observed in the supermassive black hole located at the center of the galaxy M87*, the first of which an image has been taken.

“What we see now is that there are strong magnetic fields, twisted into a spiral and organized near the black hole at the center of the Milky Way galaxy,” said Sara Issaoun, a postdoctoral fellow at the Harvard & Smithsonian Center for Astrophysics in the United States. Unidos, and co-leader of the project.

Sagittarius A* has a polarization structure surprisingly similar to that observed in the M87* black hole. “We’ve learned that strong, orderly magnetic fields are fundamental to how black holes interact with the gas and matter around them,” she said.

Observation in polarized light makes it possible to isolate part of the light radiation and reveal some of its peculiarities.

Supermassive black holes are located at the center of galaxies, with masses between one million and billions of times that of the Sun. They are supposed to have appeared very early in the Universe, but their formation is still a mystery.

The mass of black holes is so great that their gravitational attraction prevents even light from leaving — hence their name — and, therefore, they cannot be observed directly.

But with M87* in 2019 and Sagittarius A* in 2022, the EHT captured an image of the halo of light that is produced by the streams of matter and gas that the black hole attracts and partially rejects.

“By imaging the polarized light coming from the hot, glowing gas near the black holes, we are directly deducing the structure and strength of the magnetic fields that traverse the flow of gas and matter that they feed on and at the same time expel,” explained Angelo Ricarte, postdoctoral fellow at the Harvard Black Holes Initiative and co-leader of the project.

Mariafelicia De Laurentis, deputy head of the scientific department of the EHT project, pointed out that with a sample of two black holes it is important to determine how they are similar and how they differ. “In both cases, the data indicates that they have strong magnetic fields, which suggests that this may be a universal and perhaps fundamental characteristic of these types of systems.”