On 10 April 2019 astronomers for the first time captured the image of a black hole along with it’s shadow, the task was done by an international network of radio telescopes called the Event Horizon Telescope (EHT).EHT is an international collaboration whose support in the U.S. includes the National Science Foundation.
Here what you are seeing is the brand-new, first-ever close-up picture of a black hole. This image of the black hole Messier 87 (M87) is at the center of the Virgo A galaxy.
M87 is 53 million light-years away, deep in the center of a distant galaxy, surrounded by clouds of dust and gas and other matter, so no visible light telescope could see the black hole through all that gunk. It’s not the nearest black hole, or even the nearest supermassive black hole. But it’s so huge (as wide as our entire solar system, and 6.5 billion times the mass of the sun) that it’s one of the two biggest-appearing in Earth’s sky. (The other is Sagittarius A* at the center of the Milky Way.)
The image shows an intensely bright “ring of fire”, as Prof Falcke describes it, surrounding a perfectly circular dark hole. The bright halo is caused by superheated gas falling into the hole. The light is brighter than all the billions of other stars in the galaxy combined – which is why it can be seen at such distance from Earth.
To make this image, astronomers networked radio telescopes all over the world to magnify M87 to unprecedented resolution.
They called the combined network the Event Horizon Telescope.
That name is appropriate because this image isn’t the black hole itself. Black holes emit no radiation, or at least nowhere near enough to be detected using existing telescopes. But at their edges, just before the singularity’s gravity becomes too intense for even light to escape, black holes accelerate matter to extreme speeds. That matter, just before falling past the horizon, rubs against itself at high speed, generating energy and glowing. The radio waves that the Event Horizon Telescope detected were part of that process.
A team of 200 scientists pointed the networked telescopes towards M87 and scanned its heart over a period of 10 days.
The information they gathered was too much to be sent across the internet. Instead, the data was stored on hundreds of hard drives that were flown to a central processing centres in Boston, US, and Bonn, Germany, to assemble the information. Katie Bouman a PhD student at MIT developed an algorithm that pieced together the data from the EHT. Without her contribution the project would not have been possible.
- Astronomers knew that black holes were surrounded by glowing matter. But this image still answers a key question about black holes, and about the structure of our universe. We now know for certain that Einstein’s theory of relativity holds up even at the edge of a black hole, where some researchers suspected it would break down. The shape of the visible event horizon in the image is a circle, as predicted by relativity, so it confirms relativity still holds sway even in one of the most extreme environments in the universe.
- It confirms that large galaxies like Virgo A (and the Milky Way) are held together by supermassive black holes
Sera Markoff, an astrophysicist from the University of Amsterdam, said that while the collaboration hasn’t yet offered specific details on how black holes produce their giant jets. But she said that further observations of the M87 black hole, which produces dramatic jets, should help to answer those questions. The Event Horizons Telescope project will continue to add telescopes over time and improve its resolution over time, enabling it to answer more questions, she said. Specifically, she said, she’s hopeful that imaging black holes could eventually link up quantum physics and gravity.
At the end Thanks to all the scientists and astronomers for their achievment in capturing the first ever image of the black hole