Astrophysicists have now achieved what was considered impossible just a couple of decades ago, i.e. photographing one of the most fascinating and mysterious objects in the universe, a black hole. The supermassive black hole at the heart of the Messier 87 galaxy was photographed successfully using the Event Horizon Telescope (EHT). It is truly a gargantuan beast like no other, having a mass of 6.5 billion suns and measuring over 40 billion kilometers wide. This is without a doubt, a historic achievement as it opens new possibilities for studying the nature of the universe.
The EHT is a planet-sized telescope, consisting of an array of 8 interlinked radio telescopes located in the United States, Hawaii, Mexico, South America, Chile, the South Pole, and Europe working in unison to capture the image. Black holes are regions where the fabric of space-time is curved to such an extent that nothing, not even light can escape its gravitational pull. However, matter revolving around black holes becomes superheated and emits radiation which can be detected using instruments.
The image of the Messier 87 supermassive black hole shows a bright ring of fire surrounding a dark hole, which is the edge of the black hole, called the event horizon. It is located 55 million light years away from the earth.
The earth’s movement causes the image to appear from various angles from a single telescope, but a network of 8 radio telescopes spread across continents forms a kind of a giant planet-sized lens and the images taken by each one of them is coalesced into a single image by using advanced image processing software. Each of the images is hundreds of terabytes in size and had to be physically sent to processing centers on hundreds of hard drives.
This is a milestone in astrophysics and would broaden our understanding of the known universe.