Einstein was right! Black hole image confirms general theory of relativity

When matter approaches a black hole's event horizon - the point at which not even light can escape - it forms an orbiting disk.

Black holes are long-time superstars of science fiction. But their Hollywood fame is a little strange given that no-one has ever actually seen one – at least, until now. If you needed to see to believe, then thank the Event Horizon Telescope (EHT), which has just produced the first ever direct image of a black hole. This amazing feat required global collaboration to turn the Earth into one giant telescope and image an object thousands of trillions of kilometres away.

As stunning and ground-breaking as it is, the EHT project is not just about taking on a challenge. It’s an unprecedented test of whether Einstein’s ideas about the very nature of space and time hold up in extreme circumstances, and looks closer than ever before at the role of black holes in the universe.

ALSO READ: First ever images of black hole: How this landmark achievement came about

To cut a long story short: Einstein was right.

Capturing the uncapturable

A black hole is a region of space whose mass is so large and dense that not even light can escape its gravitational attraction. Against the black backdrop of the inky beyond, capturing one is a near impossible task. But thanks to Stephen Hawking’s groundbreaking work, we know that the colossal masses are not just black abysses. Not only are they able to emit huge jets of plasma, but their immense gravity pulls in streams of matter into its core.

When matter approaches a black hole’s event horizon – the point at which not even light can escape – it forms an orbiting disk. Matter in this disk will convert some of its energy to friction as it rubs against other particles of matter. This warms up the disk, just as we warm our hands on a cold day by rubbing them together. The closer the matter, the greater the friction. Matter closer to the event horizon glows brilliantly bright with the heat of hundreds of Suns. It is this light that the EHT detected, along with the “silhouette” of the black hole.

Producing the image and analysing such data is an amazingly hard task. As an astronomer who studies black holes in far away galaxies, I cannot usually even image a single star in those galaxies clearly, let alone see the black hole at their centres.

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'Seeing the unseeable': Astronomers reveal first ever photo of black hole

Black holes, phenomenally dense and coming in various sizes, are extraordinarily difficult to observe by their very nature.

Business Standard : Using a global network of telescopes to see “the unseeable,” an international scientific team on Wednesday announced a milestone in astrophysics - the first-ever photo of a black hole - in an achievement that validated a pillar of science put forward by Albert Einstein more than a century ago.

Black holes are monstrous celestial entities exerting gravitational fields so vicious that no matter or light can escape. The somewhat fuzzy photo of the black hole at the center of Messier 87, or M87, a massive galaxy residing in the center of the relatively nearby Virgo galaxy cluster, shows a glowing ring of red, yellow and white surrounding a dark center.

The research was conducted by the Event Horizon Telescope (EHT) project, an international collaboration involving about 200 scientists begun in 2012 to try to directly observe the immediate environment of a black hole. The announcement was made in simultaneous news conferences in Washington, Brussels, Santiago, Shanghai, Taipei and Tokyo.

The image was obtained using data collected in April 2017 from eight radio telescopes in six locations that essentially create a planet-sized observational dish.

The team’s observations strongly validated the theory of general relativity proposed in 1915 by Einstein, the famed theoretical physicist, to explain the laws of gravity and their relation to other natural forces.

“We have achieved something presumed to be impossible just a generation ago,” said astrophysicist Sheperd Doeleman, director of the Event Horizon Telescope at the Center for Astrophysics (CfA), Harvard & Smithsonian.

Black holes, phenomenally dense and coming in various sizes, are extraordinarily difficult to observe by their very nature. A black hole’s event horizon is the point of no return beyond which anything - stars, planets, gas, dust and all forms of electromagnetic radiation - gets swallowed into oblivion.

The M87 black hole observed by the scientific team resides about 54 million light-years from Earth and boasts an almost-unimaginable mass of 6.5 billion times that of the sun. A light year is the distance light travels in a year, 5.9 trillion miles (9.5 trillion km).