WATCH LIVE: Scientists Hold News Conference After Releasing First Ever Photo of a Black Hole

Astronomers have taken the first ever image of a black hole, which is located in a distant galaxy.

It measures 40 billion km across – three million times the size of the Earth – and has been described by scientists as “a monster”.

The black hole is 500 million trillion km away and was photographed by a network of eight telescopes across the world.

Details have been published today in Astrophysical Journal Letters.

Prof Heino Falcke, of Radboud University in the Netherlands, who proposed the experiment, told BBC News that the black hole was found in a galaxy called M87.

“What we see is larger than the size of our entire Solar System,” he said.

The Event Horizon Telescope (EHT) — a planet-scale array of eight ground-based radio telescopes forged through international collaboration — was designed to capture images of a black hole. In coordinated press conferences across the globe, EHT researchers revealed that they succeeded, unveiling the first direct visual evidence of the supermassive black hole in the centre of Messier 87 and its shadow. The shadow of a black hole seen here is the closest we can come to an image of the black hole itself, a completely dark object from which light cannot escape. The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across. While this may sound large, this ring is only about 40 microarcseconds across — equivalent to measuring the length of a credit card on the surface of the Moon. Although the telescopes making up the EHT are not physically connected, they are able to synchronize their recorded data with atomic clocks — hydrogen masers — which precisely time their observations. These observations were collected at a wavelength of 1.3 mm during a 2017 global campaign. Each telescope of the EHT produced enormous amounts of data – roughly 350 terabytes per day – which was stored on high-performance helium-filled hard drives. These data were flown to highly specialised supercomputers — known as correlators — at the Max Planck Institute for Radio Astronomy and MIT Haystack Observatory to be combined. They were then painstakingly converted into an image using novel computational tools developed by the collaboration.

“It has a mass 6.5 billion times that of the Sun. And it is one of the heaviest black holes that we think exists. It is an absolute monster, the heavyweight champion of black holes in the Universe.”

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.

The edge of the dark circle at the centre is the point at which the gas enters the black hole, which is an object that has such a large gravitational pull, not even light can escape.

The image matches what theoretical physicists and indeed, Hollywood directors, imagined black holes would look like, according to Dr Ziri Younsi, of University College London – who is part of the collaboration.

“Although they are relatively simple objects, black holes raise some of the most complex questions about the nature of space and time, and ultimately of our existence,” he said.

“It is remarkable that the image we observe is so similar to that which we obtain from our theoretical calculations. So far, it looks like Einstein is correct once again.”

But having the first image will enable researchers to learn more about these mysterious objects. They will be keen to look out for ways in which the black hole departs from what’s expected in physics. No-one really knows how the bright ring around the hole is created. Even more intriguing is the question of what happens when an object falls into a black hole.

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Source: BBC