Supermassive Black Hole Photo Proves Einstein Right Over 100 Years On

Scientists have revealed the first ever image of the black hole at the center of our Milky Way galaxy. The black hole, Sagittarius A*, is only the second black hole ever to be imaged. The image was achieved by scientists using the Event Horizon Telescope collaboration—a vast global network of radio observatories working in sync to observe radio sources associated with black holes. The highly-anticipated finding was announced at a National Science Foundation (NSF) press conference in Washington, D.C. on Thursday morning. The NSF had teased a discovery, which it had called "groundbreaking," in April without giving away any details of what it was. The photo of the black hole can be seen below.

Black holes have long inspired the imagination, often depicted as cosmic threats to space adventurers in sci-fi epics and spelling doom for those who are unfortunate enough to 'fall in'. Theoretically suggested by scientists as far back as the 1700s and later cemented by Einstein's 1916 general relativity theory—which showed that stars should leave behind a small, dense core when they collapse—black holes have become slightly less mysterious over time as astronomers have learned more about how they might form and why. Alberto Vecchio, professor of astrophysics and director of the Institute of Gravitational Wave Astronomy at the University of Birmingham, U.K., told Newsweek what the scientific community has learned from the finding. "The results are consistent with what we knew about the mass of the black hole in the centre of our galaxy, and are consistent with the presence of a black hole at the centre of the galaxy," he said. "It's another test of Einstein's theory of general relativity which again it has passed with flying colours, from what I gathered from the press release. "I think the key point—which was already demonstrated with the M87 image, but this has even more reinforced—is the exquisite technical result of being able to really map the region of the black hole at the very centre of our galaxy. Therefore, we have been able really to probe in a completely different way these extremely tiny regions of space. So that, I think, is really a technical triumph which then opens up the possibility of doing other observations of this kind." Some scientists had suspected that the discovery would indeed be the Sagittarius A* image, but this has only now been confirmed. Sagittarius A* has proved difficult to directly image so far despite having a mass 4.3 million times greater than that of our sun. This is partly because it is obscured by galactic material and partly because of the inherent challenges associated with seeing black holes. Black holes are objects with such intense gravitational fields that light cannot escape from them. Thus, they are usually observed indirectly by the warping effect they have on their surroundings. Until now, only one other black hole has ever been imaged—the black hole at the center of the galaxy M87, located more than 50 million light-years away from Earth. That image, also achieved by the NSF-funded Event Horizon Telescope project, was released in April 2019. Sagittarius A* is right next door, by comparison, a mere 26,000 light-years away.

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Scientists think that black holes are formed when stars run out of the fuel which drives their nuclear reactions. When this fuel runs out, stars no longer have the energy to support their huge masses, so they collapse in on themselves. Sometimes this simply leads to another, smaller, very dense star, but if the mass is high enough, the star collapses to a point described by some as infinitely dense—a black hole. By studying them, scientists can learn about the evolution of galaxies and perhaps even about the beginning of the universe. "For decades, astronomers have wondered what lies at the heart of our galaxy, pulling stars into tight orbits through its immense gravity," said astrophysicist Michael Johnson in a Harvard & Smithsonian Center for Astrophysics press release. "With the EHT image, we have zoomed in a thousand times closer than these orbits, where the gravity grows a million times stronger. At this close range, the black hole accelerates matter to close to the speed of light and bends the paths of photons in the warped spacetime." Update, 5/12/22, 10:13 a.m. EDT: This article has been updated to add quotes and additional information on Einstein's theory of general relativity, and has a slightly altered headline.