A team of astronomers has discovered one of the largest black holes ever found, taking advantage of a phenomenon called gravitational lensing.

The team, led by the University of Durham in the UK, used gravitational lensing – where a foreground galaxy bends the light of a more distant object and magnifies it – and supercomputer simulations at the DiRAC HPC facility, which allowed the team to examine up close how light is bent. by a black hole inside a galaxy hundreds of millions of light years from Earth.

They found an ultramassive black hole, an object more than 30 billion times the mass of our Sun, in the foreground galaxy – a scale rarely seen by astronomers.

This is the first black hole found using the technique, in which the team simulates light traveling through the universe hundreds of thousands of times. Each simulation includes a black hole of different mass, changing the journey of light to Earth.

When the researchers included an ultramassive black hole in one of their simulations, the path taken by light from the distant galaxy to reach Earth matched the path seen in real images captured by the Hubble Space Telescope.

The findings were published today in the journal Monthly Notices of the Royal Astronomical Society.

The main author, Dr. James Nightingale, from the Department of Physics at Durham University, said: "This particular black hole, which is approximately 30 billion times the mass of our sun, is one of the largest ever detected and is at the upper limit of size that we believe. that black holes can theoretically become, so it's an extremely exciting discovery."

Gravitational lensing occurs when the gravitational field of a foreground galaxy appears to bend the light of a background galaxy, meaning we observe it more than once.

Like a real lens, this also magnifies the background galaxy, allowing scientists to study it in more detail.

doctor Nightingale said: "Most of the largest black holes that we know of are in an active state, where matter pulled close to the black hole heats up and releases energy in the form of light, X-rays and other radiation."

"However, gravitational lensing makes it possible to study inactive black holes, something that is currently not possible in distant galaxies. This approach could allow us to detect many more black holes beyond our local universe and reveal how these exotic objects evolved in cosmic time. "

The study, which also includes Germany's Max Planck Institute, opens up the tantalizing possibility that astronomers could discover much more inactive and ultramassive black holes than previously thought, and investigate how they grew so large.

The story of this particular discovery began in 2004, when fellow Durham University astronomer Professor Alastair Edge noticed a giant arc of gravitational lensing when reviewing images from a galactic survey.

Fast forward 19 years and with the help of some extremely high resolution images from NASA's Hubble telescope and the DiRAC COSMA8 supercomputer facility at the University of Durham, Dr. Nightingale and his team were able to revisit that and explore it further.

The team hopes this is the first step in allowing deeper exploration of black hole mysteries, and that future large-scale telescopes will help astronomers study even more distant black holes to learn more about their size and scale.

Read more about! (Credits and Source): https://phys.org/news/2023-03-light-bending-gravity-reveals-biggest-black.html