Black holes are notorious for having such a strong gravitational pull that not even light can escape it, but that doesn’t mean that light can’t bend around it — in fact, the exceptionally strong gravity makes it more likely.
A new study by researchers observed this phenomenon for the first time, the European Space Agency (ESA) announced Wednesday.
The researchers, led by Dan Wilkins of Stanford University, used the ESA’s XMM-Newton and NASA’s NuSTAR space telescopes to observe light from behind a supermassive black hole located in the center of a nearby spiral galaxy called I Zwicky 1, about 800 million light-years from Earth.
The study did not expect to see anything, instead aiming to discover more information about a black hole’s “corona.”
The “corona,” the researchers theorized, was the result of gas that falls continuously into the black hole, creating a spinning disk around it.
The gas, though, creates a pathway for the light to bend around the black hole itself: The gas heats up to millions of degrees and generates magnetic fields that twist into knots until they snap, releasing the energy stored inside it. The burst also produces X-ray light so bright that it reflects off the gas disk and falls into the black hole as well as around it.
The light is called an “echo,” and the bend is a phenomenon that Albert Einstein predicted in his theory of General Relativity.
The phenomenon is more than just a cool trick: The light also changes color as it bends depending on the environment. Astronomers believe they can use this light to create a 3D map of a black hole and it surroundings.
“It’s a key part of the puzzle to understanding how the galaxies formed and how the universe as we know it became how it is,” Dr. Wilkins said, according to ABC 7.