
Scientists have lifted the veil on the first images ever captured of a black hole’s event horizon.

In a highly-anticipated string of press conferences held simultaneously around the world on Wednesday, the team behind the Event Horizon Telescope revealed the findings from their first run of observations.

Using a ‘virtual telescope’ built from eight radio observatories positioned at different points on the globe, the international team has spent the last few years probing Sagittarius A*, the supermassive black hole at the heart of the Milky Way, and another target called M87 in the Virgo cluster of galaxies.

While black holes are invisible by nature, the ultra-hot material swirling in their midst forms a ring of light around the perimeter that reveals the mouth of the object itself based on its silhouette. This boundary is known as the event horizon.

'We have seen what we thought was unseeable,' said EHT Director Sheperd Doeleman as he introduced the glowing orange ring that is the object at the center of Messier 87 (M87) – and our first direct look at a black hole.

The breakthrough adds major support for Einstein’s theory of General Relativity and could help to answer longstanding questions on the nature of black holes.

Scientists have lifted the veil on the first images ever captured of a black hole’s event horizon. In a highly-anticipated string of press conferences held simultaneously around the world, the team behind the Event Horizon Telescope revealed the findings from their first run of observations. The glowing orange ring shows the event horizon of M87, in the Virgo galaxy cluster

WHAT IS AN EVENT HORIZON? The event horizon is theoretical boundary around a black hole where not light or other radiation can escape. When any of that material gets too close to the edge of the hole, known as the event horizon, its atoms are ripped apart. The nuclei disappear below the horizon, the much lighter electrons get caught up in the black hole's intense magnetic field and tosses them around at high speed. This twisting motion causes them to release photons, which is the main source of emission from matter close to the black hole. Advertisement

The observations from the Event Horizon Telescope can now be counted among of the most significant scientific breakthroughs of the century.

The April 10 event focused on the results from the first full run of the observatory network, which was conducted in 2017 through the collaboration of scientists operating eight radio observatories.

While the image might seem unremarkable to some, these findings 'will transform and enhance our understanding of black holes,' said National Science Foundation Director France Cordova as she kicked off the live event in Washington DC.

Developing the technology to get the image was a 'Herculean task' in itself the researchers said; no single telescope is powerful enough to image a black hole in such detail on its own.

But, through international collaboration and an array of instruments, the team built a virtual telescope essentially as large as Earth itself, allowing them to peer into Messier 87, which lies 55 million light years away, to see the black hole at its center.

The data required more than 'half a ton of hard drives,' according to Dan Marrone, Associate Professor of Astronomy at the University of Arizona.

The eight telescopes collected 5 petabytes of data - or the 'equivalent of 5,000 years of mp3s,' or 'a lifetime of selfies for 40,000 people.'

'We now have visual evidence for a black hole,' Doeleman said. 'We now know that a black hole exists at the center of M87. Material moving around the black hole is moving at light speeds.

'We now have an entirely new way of discovering black holes that we’ve never had before, and like all new discoveries this is just the beginning.'

The data put Einstein’s theory to what could be its most rigorous test yet; the size and shape of the observed black hole can all be predicted by the General Relativity equations, which posits it to be roughly circular. The simulations (top row) are shown above alongside the image of the black hole itself (bottom row)

'We now have visual evidence for a black hole,' EHT Director Sheperd Doeleman said. 'We now know that a black hole exists at the center of M87. Material moving around the black hole is moving at light speeds.' Doeleman is shown above beside the groundbreaking image during the live event

How did scientists capture an image of a black hole? As explained in the graphic, the method relies on observing the material that swirls around the edges before falling into the black hole itself. This heats up to extreme temperatures, causing it to emit bright light that appears as a ring around the black hole

The team has been working for years to capture a silhouette of a black hole, also commonly referred to as the black hole’s shadow.

'Nature has conspired to let us see something that we thought was invisible,' Doeleman said. 'This is a long sought goal for us, and we hope that you’ll be inspired by it too.'

The data put Einstein’s theory to what could be its most rigorous test yet; the size and shape of the observed black hole can all be predicted by the General Relativity equations, which posits it to be roughly circular.

'What we’ve now confirmed is that General Relativity does not change when looking at black holes masses,' said Sera Markoff, professor of theoretical astrophysics at the University of Amsterdam.

'M87’s huge black hole mass makes it a monster even by supermassive black hole standards. You’re basically looking at a supermassive black hole that is almost the size of our solar system.'

The researchers estimate its mass to be roughly 6.5 billion times the mass of the sun.

While black holes are invisible by nature, the ultra-hot material swirling in their midst forms a ring of light around the perimeter that reveals the mouth of the object itself based on its silhouette. This boundary is known as the event horizon. A simulation of the black hole is pictured alongside the history-making new image above

Mareki Honma of the National Astronomical Observatory of Japan unveils the first image of a black hole during a press conference in Tokyo, Japan. Simultaneous press conferences were held all around the world on Wednesday

The effort has been working for years to capture a silhouette of a black hole, also commonly referred to as the black hole’s shadow. This is done by observing the ultra-hot material swirling around the black hole, as explained in the graphic above

The breakthrough adds major support for Einstein’s theory of General Relativity and helps to confirm our understanding of gravity. Simulations of the black hole are shown above

'The galaxies are growing, and we think it's through these types of interactions that black holes help shape the largest structures in galaxies and make them look the way they do today,' Markoff said.

'By looking at two black holes with extremely opposite energy, we can better understand the influence of black holes in the long course of our history.'

Through international collaboration, the team built a virtual telescope essentially as large as Earth itself, allowing them to peer into the center of the Virgo A galaxy

The international collaboration that makes up the Event Horizon Telescope effort includes observatories in the South Pole, Europe, South America, Africa, North America, and Australia – all of which must be pointed directly at the object to measure the surrounding activity.

Now, the researchers have a ton of data to pore through and countless analyses to run.

The many different teams will each develop their own models to compare against each other on a larger scale.

Eventually, they'll move on to study Sagittarius A, the supermassive black hole at the center of our own galaxy.

'We've seen the unseeable,' said Avery Broderick, Associate Professor in the Department of Physics & Astronomy at the University of Waterloo. 'Now what does it all mean?'

Pictured from left to right: Event Horizon Telescope Director Sheperd Doeleman, National Science Foundation Director France Cordova, University of Arizona Associate Professor of Astronomy Dan Marrone, University of Waterloo Associate Professor Avery Broderick and University of Amsterdam Professor of Theoretical High Energy Astrophysics Sera Markoff