![]() One might think that black holes only swallow matter – this was what scholars had believed for a long time…until one day Mr. ![]() The image you see is an amalgam of data taken over eight sites in four days in April 2017 it was finally put together using techniques of image restoration to reconstruct a singular image from the large body of data. The aperture of this telescope becomes the distance between the two furthest telescopes – in this case nearly the diameter of the Earth! This vastly increases the resolution of the telescope and allows us to take images of objects that are far away. Instead of building one large telescope, the team decided that they would align the different EHT telescopes at the black hole at the same time, creating a large, “virtual” telescope. To capture a reasonably clear image of an object so far from Earth, the telescope would require a very large aperture (the size of opening of the lens) to gather enough light from it. This remarkable image was not taken by a single telescope, but rather an amalgam of images taken across eight telescopes on Earth known as the Event Horizon Telescope (EHT). Myth: This picture was taken by one telescope. Nothing escapes a black hole – not even light. You may recall the concept of escape velocity from high school physics black holes are so small and massive that the escape velocity is greater than the speed of light. Eventually, the density of the star becomes high enough that it creates a very strong gravitational pull – and this is a black hole. As the internal pressure continues to decrease, gravity causes the star to further collapse onto itself. In a dying star, there is a reduction in internal pressure due to the fusing of heavier elements. The black holes we can see in the sky are formed by a process known as gravitational collapse. Actually, owing to the relatively tiny mass of the Sun, it can never turn into a black hole – so we won’t have to worry about our Sun turning into a black hole any time soon! To put things into perspective, if the Sun were a black hole, it would have a radius of approximately 2.95 km in comparison, the current radius of the Sun is 696,340 km. (Here M is the mass of the star, c is the speed of light, and G is the gravitational constant.) This occurs when the size of a star collapses to a small enough size – more specifically, smaller than the Schwarzschild radius. Mass bends the fabric of space-time itself around a black hole’s event horizon, the space-time is bent in a way that even light cannot escape. Einstein’s theory of relativity can be elegantly summed up in twelve words from John Wheeler – “Space-time tells matter how to move matter tells space-time how to curve. Photo credit : Event Horizon Telescope Collaboration īut first we have to answer the question – what exactly are black holes, and how are they formed?Īlthough the existence of bas a solution to the Einstein field equations. ![]() The black hole at the center of the Messier 87 (M87) galaxy, in the constellation Virgo The black hole in question is a supermassive one, 2.4 billion times the mass of the Sun, at the center of the M87 galaxy, about 53 million light years from Earth. This remarkable picture occupied headlines worldwide, and rightfully so – we never thought we would ever be able to capture a black hole in an image that can be passed around the world. On April 10, 2019, a team of scientists made history by capturing the first ever image of a black hole.
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