'Astounding': Astronomers photograph the supermassive black hole at the center of the Milky Way

Thursday's mindblowing breakthrough will be published in a forthcoming special issue of The Astrophysical Journal Letters.

The colossal object, known as Sagittarius A*, is located 27,000 light-years away from Earth in the direction of the constellation Sagittarius. It was first discovered in 1974 by Bruce Balick of the Astronomy Department at the University of Washington in Seattle and Cornell University's Robert Brown.

Sagittarius A*'s properties were later confirmed in the 1990s by a world-renowned group of researchers – Andrea Ghez, an astrophysicist and professor in the Department of Physics and Astronomy at the University of California, Los Angeles,Reinhard Genzel of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany, and the University of California Berkeley, and Oxford University's Sir Roger Penrose.

Using radio telescopes to peer through the haze of interstellar dust that absorbs visible light, Ghez, Genzel, and Penrose observed stars deep inside the galactic core whipping around an invisible central volume at millions of miles per hour. Based on the stars' phenomenal velocities and the distances that they were traveling, Ghez, Genzel, and Penrose calculated the mass of whatever it was that the stars were orbiting. The math led to the inescapable conclusion that the only possibility was a supermassive black hole weighing in at four million times the mass of our Sun.

Ghez and her colleagues were awarded the 2020 Nobel Prize in Physics for their discovery.

Today, humanity was rewarded with its first mesmerizing glimpse into the Stygian soul of our swirling island universe.

"The breakthrough follows the EHT collaboration’s 2019 release of the first image of a black hole, called M87*, at the center of the more distant Messier 87 galaxy," the organizations said in their press release.

They explained:

Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a 'shadow') surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

Because the black hole is about 27,000 light-years away from Earth, it appears to us to have about the same size in the sky as a donut on the Moon. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single 'Earth-sized' virtual telescope [1]. The EHT observed Sgr A* on multiple nights, collecting data for many hours in a row, similar to using a long exposure time on a camera.

Quoted in The Washington Post, University of Arizona astronomer Feryal Özel, who introduced the picture, said it was “the first direct image of the gentle giant in the center of our galaxy.”

In it, Özel continued, "we find a bright ring surrounding the black hole shadow. It seems that black holes like doughnuts," she joked.

"Getting to this image wasn't an easy journey," Özel added. "It took several years to refine the image and confirm what he had."

The global scientific community is ecstatic.

“We were stunned by how well the size of the ring agreed with predictions from Einstein’s Theory of General Relativity," said EHT Project Scientist Geoffrey Bower from the Institute of Astronomy and Astrophysics, Academia Sinica in Taipei, Japan. "These unprecedented observations have greatly improved our understanding of what happens at the very center of our galaxy and offer new insights on how these giant black holes interact with their surroundings.”

The team also noted how similar Sagittarius A* and M87* appear despite the enormous disparity in their respective sizes.

"We have two completely different types of galaxies and two very different black hole masses, but close to the edge of these black holes they look amazingly similar,” says Sera Markoff, Co-Chair of the EHT Science Council and a professor of theoretical astrophysics at the University of Amsterdam in the Netherlands. "This tells us that General Relativity governs these objects up close, and any differences we see further away must be due to differences in the material that surrounds the black holes.”

Ryan Hickox, an astrophysicist at Dartmouth College, told Space.com that "this is an astounding achievement" and that "I think I speak for a large number of my astronomy colleagues when I say how remarkably grateful we are."

View it below:

Read the National Science Foundation's full press release here.

Black holes, the densest regions of space and time, are gravitationally infinite maelstroms so powerful that neither matter nor light can escape. These innumerable interstellar vagabonds rotate through the void, feeding on wayward elemental material. Black holes do not discriminate when it comes to what they will consume. Anything that crosses into their path and breaches the event horizon is lost forever in the relativistic abyss of cosmic singularity.

There are three classifications, however, individuals are distinguishable by only two fundamental quantum properties: mass and spin. Somewhat counterintuitively, black holes are the simplest cosmological macro objects proven to exist.

Stellar-mass black holes occur when the cores of dying giant stars collapse while their outer layers are blasted away in spectacular supernova explosions. They range in mass from three to <100 times that of our Sun.

Intermediate-mass black holes contain 100 to >100,000 solar masses and are the products of collisions between stellar-mass black holes and other massive bodies, such as one of their countless cousins, neutron stars, or unfortunate planetary systems. Their presence was confirmed earlier this year when astronomers at the University of Utah spotted one more than two million light-years away within a stellar cluster in the Andromeda galaxy. Some physicists have theorized that intermediate-mass black holes could be primordial black holes, which are some of the oldest objects in the Universe, having been born in the Big Bang.

Supermassive black holes are the unseeable sums of untold stellar-mass and intermediate-mass black hole cannibalism. They are believed to spin at the heart of every galaxy in the Universe. The smallest specimens are at least 100,000 times as massive as our Sun. There is no limit to how big supermassive black holes can become. The largest known supermassive black hole, Ton 618, has 66 billion times the mass of our Sun.