Astronomers for first time have unveiled direct image of black hole. It shows bright-orange circular image with dark central region of black hole located at the centre of the Messier 87 (M87) galaxy in the Virgo galaxy cluster. It was taken by Event Horizon Telescope (EHT) Collaboration in April 2017. This first image comes more than 100 years after these super-dense extreme-gravity regions of space-time were theorised as consequence of Albert Einstein's General Theory of Relativity.
- It is super-dense extreme-gravity regions of space-time from where even light is unable to escape.
- It is formed mainly by massive collapsing of star after it starts extinguishing or dying.
- The space-time around it gets incredibly bent that nothing is able to escape from its gravity
Note: Black holes cannot be observed directly by any of the scientific instruments since they are completely ‘dark’ and do not emit or reflect any light, nor any other electromagnetic radiation.
Event Horizon Telescope
- It comprises of eight radio telescopes — located in Hawaii and Mexico, in mountains of Arizona, in Spanish Sierra Nevada, in Atacama Desert of Chile and near South Pole in Antarctica.
Image capturing process
- The black hole, whose image was captured is at distance of 55 million light-years from earth. It has mass 6.5 billion times that of the Sun.
- Astronomers had built elaborate and complex network of massive telescopes around the world and devise ingenious new techniques, to get first visual evidence of a black hole.
- They had captured very high frequency microwave radiation originating from near black hole 55 million years ago.
- Each of these Event Horizon Telescope captured only small piece of area. The data from all those were then feeded into central super-computer which, over several months, created complete picture of black hole.
- The outer orange disk in image of black hole represents the radiation being emitted by gases and other objects that exist just outside the black hole. The inner dark circular area in the image is actually the black hole.