Scientists have glimpsed the event horizon of a black hole for the very first time.
Until now, every image of a black hole you have ever seen has been an artist's impression.
"We've been studying black holes so long that sometimes it's easy to forget that none of us has actually seen one," said France Cordova, director of the US National Science Foundation, at one of seven simultaneous press conferences where the scientists announced their findings to the world.
The first image shows a bright fringe of gas, which is being squeezed and heated as it falls towards the event horizon of a supermassive black hole at the centre of M87, a galaxy near our own Milky Way.
This cosmic monster sits 55 million light-years from Earth and is 6.5 billion times heavier than the Sun.
Its historic portrait is the result of decades of theoretical predictions and technical advances.
"This is an extraordinary scientific feat accomplished by a team of more than 200 researchers," said Dr Sheperd Doeleman from the Harvard-Smithsonian Centre for Astrophysics.
"We have achieved something presumed to be impossible just a generation ago."
He pioneered the instrument making it all possible: the
Event Horizon Telescope (EHT), which is actually a network of radio
telescopes spanning the globe.
Their combined observing power has been trained on two very large black holes, to try and obtain some historic snapshots.
On Wednesday the EHT team called a press conference. Seven press conferences, to be exact, on four continents and in five languages, all starting at 11:00pm AEST.
Nobody outside the project knew exactly what they would be announcing, but they had declared it was "a groundbreaking result".
The finding was also announced today in a series of six papers published in a special issue of The Astrophysical Journal Letters.
One of the telescopes in the network is the James Clerk Maxwell Telescope on top of Mauna Kea peak in Hawaii, where Australian Jessica Dempsey is deputy director.
"We've made a dish the size of the planet," she said.
By combining results from nine separate dishes, scattered from Antarctica to Europe, Dr Dempsey and her colleagues can create a virtual telescope 9,000 kilometres in diameter, making it the world's biggest camera.
"To give you an idea of how small a thing you can see, if you're sitting in a pub in Perth, you would be able to see a guy sitting in the pub in Sydney, not only would you be able to see him, you'd be able to see his eye colour, and you'd be able to see the brand of beer he was drinking," she told ABC's Catalyst earlier this year.
Getting this global telescope network in sync has been an exercise in precision. The operators had to know the timing of the signals at every one of these telescopes to a billionth of a second to make sure they were all looking at the same thing at the same time.
These locations included volcanoes in Hawaii and Mexico, mountains in Arizona and the Spanish Sierra Nevada, the Chilean Atacama Desert, and Antarctica.
"We are stacking impossible task on top of impossible task and this shouldn't work," Dr Dempsey said.
But as tonight's announcement made clear — it did work.
"It's the first time that we've had the resolution to look close enough to try to capture a picture of an actual black hole," said Professor Tamara Davis, an astrophysicist from the University of Queensland.
The researchers have targeted two supermassive black holes, including the one in the centre of our own Milky Way galaxy, Sagittarius A*.
This is situated 26,000 light-years from Earth and is 4 million times the mass of our Sun, but by supermassive black hole standards, it is pretty small.
The other is much bigger, but also much further away, at the centre of the nearby galaxy M87. And that is the one whose image was released on Wednesday.
"In both cases we're hoping to see the image of the black hole that's at the centre of the galaxy — and that everything else is orbiting around," Professor Davis explained.
She is not directly involved in the project but is an interested, and impatient, observer.
"It would be amazing to be able to see this and confirm that really heavy thing that's in the centre of the galaxy is definitely a black hole, and thus to confirm a bunch of the predictions of relativity," she said.
Until now, every image of a black hole you have ever seen has been an artist's impression.
"We've been studying black holes so long that sometimes it's easy to forget that none of us has actually seen one," said France Cordova, director of the US National Science Foundation, at one of seven simultaneous press conferences where the scientists announced their findings to the world.
The first image shows a bright fringe of gas, which is being squeezed and heated as it falls towards the event horizon of a supermassive black hole at the centre of M87, a galaxy near our own Milky Way.
This cosmic monster sits 55 million light-years from Earth and is 6.5 billion times heavier than the Sun.
Its historic portrait is the result of decades of theoretical predictions and technical advances.
"This is an extraordinary scientific feat accomplished by a team of more than 200 researchers," said Dr Sheperd Doeleman from the Harvard-Smithsonian Centre for Astrophysics.
"We have achieved something presumed to be impossible just a generation ago."
Their combined observing power has been trained on two very large black holes, to try and obtain some historic snapshots.
On Wednesday the EHT team called a press conference. Seven press conferences, to be exact, on four continents and in five languages, all starting at 11:00pm AEST.
Nobody outside the project knew exactly what they would be announcing, but they had declared it was "a groundbreaking result".
The finding was also announced today in a series of six papers published in a special issue of The Astrophysical Journal Letters.
A telescope the size of a planet
The EHT initiative kicked off seven years ago with the aim of directly observing the immediate environment of a black hole.One of the telescopes in the network is the James Clerk Maxwell Telescope on top of Mauna Kea peak in Hawaii, where Australian Jessica Dempsey is deputy director.
"We've made a dish the size of the planet," she said.
By combining results from nine separate dishes, scattered from Antarctica to Europe, Dr Dempsey and her colleagues can create a virtual telescope 9,000 kilometres in diameter, making it the world's biggest camera.
"To give you an idea of how small a thing you can see, if you're sitting in a pub in Perth, you would be able to see a guy sitting in the pub in Sydney, not only would you be able to see him, you'd be able to see his eye colour, and you'd be able to see the brand of beer he was drinking," she told ABC's Catalyst earlier this year.
Getting this global telescope network in sync has been an exercise in precision. The operators had to know the timing of the signals at every one of these telescopes to a billionth of a second to make sure they were all looking at the same thing at the same time.
These locations included volcanoes in Hawaii and Mexico, mountains in Arizona and the Spanish Sierra Nevada, the Chilean Atacama Desert, and Antarctica.
"We are stacking impossible task on top of impossible task and this shouldn't work," Dr Dempsey said.
But as tonight's announcement made clear — it did work.
"It's the first time that we've had the resolution to look close enough to try to capture a picture of an actual black hole," said Professor Tamara Davis, an astrophysicist from the University of Queensland.
This is situated 26,000 light-years from Earth and is 4 million times the mass of our Sun, but by supermassive black hole standards, it is pretty small.
The other is much bigger, but also much further away, at the centre of the nearby galaxy M87. And that is the one whose image was released on Wednesday.
"In both cases we're hoping to see the image of the black hole that's at the centre of the galaxy — and that everything else is orbiting around," Professor Davis explained.
She is not directly involved in the project but is an interested, and impatient, observer.
"It would be amazing to be able to see this and confirm that really heavy thing that's in the centre of the galaxy is definitely a black hole, and thus to confirm a bunch of the predictions of relativity," she said.
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