Researchers have made unexpected conclusions about a black hole in the galaxy: “Like a football”

The black hole at the center of our galaxy is spinning rapidly and dragging space-time with it, scientists say.

A new study has found that the supermassive black hole at the center of our galaxy, Sagittarius A*, is rapidly spinning and altering the space-time around it.

As CNN explains, space-time is a four-dimensional continuum that describes how we see space, combining one-dimensional time and three-dimensional space together to represent a spatial fabric that bends in response to massive celestial bodies.

A team of physicists observed the black hole, which lies 26,000 light-years from Earth, using NASA’s Chandra X-ray Observatory, a telescope designed to detect X-rays from hot regions of the Universe. According to a study published in Monthly Notices, scientists calculated the rotation rate of Sagittarius A* using the so-called outflow method, which looks at radio waves and X-rays that can be detected in the material and gases surrounding black holes, otherwise known as an accretion disk. Royal Astronomical Society.

Researchers have confirmed that the black hole is spinning, causing the so-called Lens-Thirring effect. The Lens-Thirring effect, also known as frame drag, is what happens when a black hole drags spacetime along with its spin, says lead study author Ruth Daly, a professor of physics at Pennsylvania State University who developed the outflow technique over a decade years ago.

Since inventing the outflow method, Daly has worked to determine the spin of various black holes and authored a 2019 study that examined more than 750 supermassive black holes.

“With this kind of rotation, Sagittarius A* would dramatically change the shape of space-time in its vicinity,” says Ruth Daly. “We are used to thinking and living in a world where all spatial dimensions are equivalent – the distance to the ceiling, the distance to the wall and the distance to the floor… they are all linear, it does not mean that one of them is completely compressed compared to the others.” .

“But if you have a rapidly spinning black hole, the spacetime around it is asymmetrical—the spinning black hole drags all of spacetime with it… it compresses spacetime and it looks like a football,” she said.

According to Ruth Daly, the change in space-time is nothing to worry about, but illuminating the phenomenon could be very useful for astronomers.

“This is a wonderful tool for understanding the role that black holes play in the formation and evolution of galaxies,” she said. “The fact that they are dynamic objects that can spin… And then that can affect the galaxy they’re in is very exciting and very interesting.”

The spin of a black hole is assigned a value between 0 and 1, where 0 means the black hole is not spinning and 1 is the maximum spin value. Previously, there was no consensus on the meaning of Sagittarius A*’s rotation, Daly notes.

Knowing a black hole’s mass and spin helps astronomers understand how a black hole could form and evolve, Daly explains.

According to Dejan Stojkovic, a professor of cosmology at the University at Buffalo who was not involved in the study, black holes formed by the merger of smaller black holes tend to have low spin. However, a black hole formed by accretion of surrounding gas would have a high spin value.

The speed at which Sagittarius A* rotates indicates that a significant portion of the black hole’s mass came from accretion, he said.

“The question of whether our central galactic black hole is spinning or not, or how fast it is spinning, is quite important,” Stojkovic noted. “Ultimately, we want to measure the properties of the center of our galaxy as best as possible. In this way, we can learn about the history and structure of our galaxy, test our theories, or even infer the existence of some very interesting and intriguing objects, such as wormholes.”