On Wednesday morning, the world got to see the unseeable.
Scientists released an image of a black hole captured by the Event Horizon Telescope, a project of eight radio-based telescopes tasked with capturing a visual representation of a black hole.
Black holes, long theorized about but never photographed, are technically impossible to see because everything – even light – is drawn in by their gravitational pull.
“This is the strongest evidence we have to date of the existence of black holes,” said Sheperd Doeleman, an astrophysicist with the Center for Astrophysics.
The photo captures a ring-like structure with a dark middle, which is the shadow of the black hole, at the center of a galaxy known as Messier 87.
“If immersed in a bright region, like a disc of glowing gas, we expect a black hole to create a dark region similar to a shadow – something predicted by Einstein’s general relativity that we’ve never seen before,” said Heino Falcke of Radboud University in the Netherlands, the chairman of the Event Horizon Telescope Science Council. “This shadow, caused by the gravitational bending and capture of light by the event horizon, reveals a lot about the nature of these fascinating objects and allowed us to measure the enormous mass of M87’s black hole.”
Photos: Space Over Time
The black hole, which is highlighted by radiating hot gas orbiting around it, is about 55 million light years from Earth. That means the image shows what the black hole looked like that many years ago.
Its mass is 6 1/2 billion times that of the sun and it was in a “modest active state” at the time of the photo, according to Sera Markoff, a member of the Event Horizon Telescope Science Council. Black holes are thought to be the “driving engines” of galaxies, “affecting the largest scales of the universe,” she added.
The mission is a “high-risk but high-payoff endeavor,” Doeleman said.
Messier 87’s black hole is just one of two researchers are pursuing. The other, Sagittarius A*, is in Earth’s galaxy, the Milky Way.
Messier 87’s black hole was easier to capture, according to researchers. “We’re not promising anything” on images of Sagittarius A*, Doeleman said.
Researchers said they will continue to refine the image and study the discovery, which brought astonishment and wonder to the team of over 200 people involved in the research, Doeleman said.
“We’ve been at this so long that there’s such a buildup,” he said. “It was such a relief to see this but also a surprise.”
Astrophysicist Avery Broderick, a member of the Event Horizon Telescope Collaboration, said he was “a little stunned” that the image matched simulations so closely.
Markoff said the team has not started a full analysis of the image and that it will help researchers create models to understand what exactly happens around black holes.