By the standards of other supermassive black holes, the scientists said, the hole in the heart of our Milky Way galaxy is relatively quiet — as quiet as something that can devour stars, reaching temperatures measured in trillions of degrees.
Ferial Ozil, an astronomer at the University of Arizona, described the achievement as “the first direct image of the gentle giant at the center of our galaxy.”
“We found a bright ring surrounding the shadow of the black hole,” she said. “Black holes look like donuts.”
The image was taken by a global group of astronomical observatories known as event horizon telescope. Three years ago, the project was produced The first image of a black holein the galaxy Messier 87.
The black hole at the center of the Milky Way It is more than a thousand times smaller than that of Messier 87. But in cosmological terms, it is the closest to home. The unveiling of the photo at the National Press Club in Washington was part of simultaneous media events on several continents. The photo was kept under wraps, waiting for the unveiling at 9:07 a.m. ET.
The achievement, with support from the National Science Foundation, relied on contributions from more than 300 scientists at 80 institutions, including eight telescopes. The data collected took years to process and analyze. The black hole itself is not static but does change in appearance over short time scales, challenging scientists to produce a single image that matches what their telescopes have observed. The pandemic has added its own challenges.
“The epidemic has slowed us down, but it hasn’t been able to stop us,” Vincent Fish, a research scientist at the MIT Haystack Observatory, said at the press conference.
The work eventually proved exciting.
“What’s more fascinating than seeing a black hole at the center of our Milky Way?” said team member Katherine Bowman, a computational imaging scientist at Caltech.
Shepherd Doelman, an astronomer at the Harvard-Smithsonian Center for Astrophysics and founding director of the Event Horizon Telescope, said in an interview before the briefing Thursday.
The central black hole of the Milky Way has so far been inferred from its effect on stars and dust in its vicinity, rather than directly observed. It’s very far away – about 27,000 light-years away – and despite its “enormous” rating, Not very big in the grand scheme of things, which makes direct observation with telescopes very difficult.
this challenge It led to the creation of the Event Horizon Telescope, which is not one telescope but one of them. The project uses a monitoring technique known as very long fundamental interferometry, which requires careful calibration to allow multiple radio dishes spread across the planet to act as if it were a single Earth-sized instrument. The consortium claims that this technology allows for the separation of distant objects that would be equivalent to being able to detect a ping-pong ball on the moon.
Black holes come in two scales: “stellar mass” that forms when stars collapse, and “supermass,” which are monsters that can weigh Millions or even billions of times larger than our sun and that’s what the Event Horizon Telescope is designed to detect.
The black hole attracts a lot of gas to it. Its gravity is so strong that the material around it is irresistible. But it pulls it into a very small space,” Doelman said. “Imagine that you are sucking an elephant through a straw.”
The event horizon of a black hole is the boundary of no return – the point at which a piece of fallen matter disappears into an inescapable gravitational well. Strange and mysterious like a black hole, Earthlings should understand that It poses no threat to our world and is basically just a piece of galactic furniture.
Albert Einstein’s 1915 general theory of relativity postulated that gravity is the result of massive objects bending the fabric of spacetime. When theorists deduced the implications of Einstein’s equations, they realized that an object of sufficient mass would create such intense gravity that not even light could escape.
The idea that such black holes exist remained largely in the theoretical field until the late twentieth century. gravitational waves from the collision of black holes in 2016.
Decades ago, astronomers realized that something in the heart of the Milky Way was emitting massive amounts of radiation. It was the brightest object near the constellation Sagittarius. Was it caused by a black hole? That became the consensus. The luminous astronomical object became known as Sagittarius A*.
Astrophysicists Andrea Geis and Reinhard Genzel have been awarded the prize Nobel Prize in Physics in 2020 to discover that stars in the center of the Milky Way were moving in a pattern that corresponds to orbits around a supermassive black hole.
Astrophysicists believe that black holes are common at the cores of galaxies – and in some way are central to the evolution of galaxies – although the chicken-and-egg question remains unresolved. One possibility is that black holes are the seed of a galaxy. The other is that black holes gradually form as stars fall into the galactic central gravitational well.