In the News
Accomplishing what was previously thought to be impossible, a team of international astronomers has captured an image of a black hole’s silhouette.
Evidence of the existence of black holes – mysterious places in space where nothing, not even light, can escape – has existed for quite some time, and astronomers have long observed the effects on the surroundings of these phenomena.
In the popular imagination, it was thought that capturing an image of a black hole was impossible because an image of something from which no light can escape would appear completely black.
For scientists, the challenge was how, from thousands or even millions of light-years away, to capture an image of the hot, glowing gas falling into a black hole. An ambitious team of international astronomers and computer scientists has managed to accomplish both.
Working for well over a decade to achieve the feat, the team improved upon an existing radio astronomy technique for high-resolution imaging and used it to detect the silhouette of a black hole – outlined by the glowing gas that surrounds its event horizon, the precipice beyond which light cannot escape. Learning about these mysterious structures can help students understand gravity and the dynamic nature of our universe, all while sharpening their math skills.
How They Did It
Though scientists had theorized they could image black holes by capturing their silhouettes against their glowing surroundings, the ability to image an object so distant still eluded them.
A team formed to take on the challenge, creating a network of telescopes known as the Event Horizon Telescope, or the EHT.
They set out to capture an image of a black hole by improving upon a technique that allows for the imaging of far-away objects, known as Very Long Baseline Interferometry, or VLBI.
Telescopes of all types are used to see distant objects.
The larger the diameter, or aperture, of the telescope, the greater its ability to gather more light and the higher its resolution (or ability to image fine details).
To see details in objects that are far away and appear small and dim from Earth, we need to gather as much light as possible with very high resolution, so we need to use a telescope with a large aperture.
That’s why the VLBI technique was essential to capturing the black hole image.
VLBI works by creating an array of smaller telescopes that can be synchronized to focus on the same object at the same time and act as a giant virtual telescope.
In some cases, the smaller telescopes are also an array of multiple telescopes. This technique has been used to track spacecraft and to image distant cosmic radio sources, such as quasars.
Making up one piece of the EHT array of telescopes, the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile has 66 high-precision antennas. Image credit: NRAO/AUI/NSF | + Expand image
The aperture of a giant virtual telescope such as the Event Horizon Telescope is as large as the distance between the two farthest-apart telescope stations – for the EHT, those two stations are at the South Pole and in Spain, creating an aperture that’s nearly the same as the diameter of Earth. Each telescope in the array focuses on the target, in this case the black hole, and collects data from its location on Earth, providing a portion of the EHT’s full view. The more telescopes in the array that are widely spaced, the better the image resolution.
This video shows the global network of radio telescopes in the EHT array that performed observations of the black hole in the galaxy M87. Credit: C. Fromm and L. Rezzolla (Goethe University Frankfurt)/Black Hole Cam/EHT Collaboration | Watch on YouTube
To test VLBI for imaging a black hole and a number of computer algorithms for sorting and synchronizing data, the Event Horizon Telescope team decided on two targets, each offering unique challenges.
The closest supermassive black hole to Earth, Sagittarius A*, interested the team because it is in our galactic backyard – at the center of our Milky Way galaxy, 26,000 light-years (156 quadrillion miles) away. (An asterisk is the astronomical standard for denoting a black hole.
) Though not the only black hole in our galaxy, it is the black hole that appears largest from Earth. But its location in the same galaxy as Earth meant the team would have to look through “pollution” caused by stars and dust to image it, meaning there would be more data to filter out when processing the image.
Nevertheless, because of the black hole’s local interest and relatively large size, the EHT team chose Sagittarius A* as one of its two targets.
A close-up image of the core of the M87 galaxy, imaged by the Chandra X-ray Observatory. Image credit: NASA/CXC/Villanova University/J. Neilsen | + Expand image
This image from NASA's Hubble Space Telescope shows a jet of subatomic particles streaming from the center of M87*. Image credits: NASA and the Hubble Heritage Team (STScI/AURA) | + Expand image
First ever black hole image released
By Pallab Ghosh Science correspondent, BBC News
Image copyright EHT Image caption The first ever picture of a black hole: It's surrounded by a halo of bright gas
- 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.
- It was captured by the Event Horizon Telescope (EHT), a network of eight linked telescopes.
- 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.
“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.”
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Media captionM87: The significance of the first ever image of a black hole
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 Story Behind the First Picture Taken of a Black Hole
On Wednesday, April 10th, the world was treated to something unprecedented – the first-ever image of a black hole! Specifically, the image captured the Supermassive Black Hole (SMBH) at the center of M87 (aka. Virgo A), a supergiant elliptical galaxy in the Virgo constellation.
Already, this image is being compared to pictures like the “pale blue dot” taken by the Voyager 1 mission or the “Earthrise” image taken by Apollo 8. Like these images, the picture of the M87 black hole has captured the imagination of people all around the world.
This accomplishment drew on years of hard work involving astronomers, observatories and scientific institutions from all around the world. As with most accomplishments of this caliber, countless people played a role and deserve credit for making it happen.
But as always, there were a handful of people whose contributions really stand out. In addition, capturing the first-ever image of a black hole depended a lot of specialized technology and scientific methods, which also deserve attention. You might say that his historic accomplishment had a historic buildup!
Those Who Made it Happen:
Since the EHT project released the first image of a black hole, Katherine Bouman has become something of a household name. But just who is this black hole hunter whose work has helped us to look into the face of one of the most mysterious phenomena in the Universe?
RELATED: KATIE BOUMAN: THE BRILLIANT MIND THAT BROUGHT US THE IMAGE OF A BLACK HOLE
Bouman received her Ph.D. Electrical Engineering and Computer Science at the Massachusetts Institute of Technology (MIT) in 2017. Since then, Bouman has worked as a postdoctoral researcher with the Event Horizon Telescope project, where she applied emerging computational methods to push the boundaries of imaging technology.
The story behind the first ever black hole image – Physics World
In the May edition of the Physics World Stories podcast, Andrew Glester reflects on the biggest astronomy story of the year – the first ever image of a black hole and its “shadow”.
Unless you’ve been living in a black hole yourself, you will have seen the glowing donut/eye of Sauron/smiley face, which is actually the supermassive black hole at the centre of the M87 elliptical galaxy, some 55 million light-years from Earth.
The image represents an incredible feat of science and engineering, produced from petabytes of data captured by the Event Horizon Telescope (EHT), a network of individual radio telescopes and telescopic arrays scattered across the globe. The EHT team reported the results in six papers in a special issue of Astrophysical Journal Letters, which is published by the Institute of Physics on behalf of the American Astronomical Society.
To find out more about the story behind the discovery, Glester catches up with three scientists from the EHT team who also hold positions at Radboud University in the Netherlands.
First up is Monika Mościbrodzka, a member of EHT’s data analysis team who speaks about the significance of the discovery and the future prospects for the project. “Black holes are no longer just a theory.
It’s now reality”, she says.
Global networking: the Event Horizon Telescope combines the signals of eight radio telescope observatories including the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile and the South Pole Telescope (SPT) in Antarctica. (Courtesy: Akiyama et al and ApJL)
Meanwhile, Freek Roelof explains how the group generated the image from all the raw radio wave data. He worked on data collection at the Submillimeter Telescope (SMT) on Mount Graham, Arizona. When not doing cutting edge science Roelof plays the guitar and you can hear some of his black-hole-inspired songs in the podcast.
Since the publication of the image, many people have asked the question: “Why did these astronomers look all the way to the M87 galaxy, when we have a black hole – Sagittarius A* – at the centre of our own galaxy?” The reason comes down to scale. Despite being a thousand times further away, the black hole at the centre of M87 is a whopping 0.7 billion solar masses, a thousand times more massive than Sagittarius A*.
Historic 1st Photo of a Black Hole Named Science Breakthrough of 2019
The Event Horizon Telescope, a planet-scale array of eight ground-based radio telescopes forged through international collaboration, captured this image of the supermassive black hole in the center of the galaxy M87 and its shadow.
(Image: © EHT Collaboration)
The first image of a black hole, previously thought nigh impossible to capture, was named the top scientific breakthrough of 2019 by the journal Science.
Black holes have gravitational pulls so powerful that, past thresholds known as their event horizons, nothing can escape, not even light. Supermassive black holes millions to billions of times the mass of our sun are thought to lurk in the hearts of virtually every large galaxy, influencing the fate of every star caught in their gravitational thrall.
Using Albert Einstein's theory of general relativity, German physicist Karl Schwarzschild was the first to lay the foundation of the science describing black holes.
In the decades since then, scientists have detected numerous signs of black holes, such as the effects their gravity have on their surroundings and the ripples in the fabric of space and time known as gravitational waves emitted when they collide.
Related: The Future of Black Hole Photography: What's Next?
Can we photograph a black hole?
Although researchers had spent years theorizing about black holes, few imagined they would ever get a chance to actually see one. Since black holes reflect no light, they are perfectly camouflaged against the darkness of space.
In addition, black holes are very small by cosmic standards — for example, the supermassive black hole Sagittarius A*, located in the Milky Way's core, is about 4 million times the mass of the sun but only about 14.6 million miles (23.
6 million kilometers) in diameter, half as wide as the distance between Mercury and the sun.
However, about two decades ago, astronomers began wondering if they might be able to capture a photo of a black hole if it was backlit against the hot swirling gases close to its event horizon.
These gases shine bright at many wavelengths of light, including ones that could pierce any murky clouds that may surround them.
Scientists could then detect a dark spot against a bright background, the so-called black hole shadow.
In April, the international Event Horizon Telescope consortium revealed they successfully captured the first images of a black hole shadow. “Seeing is believing,” Avi Loeb, chair of astronomy at Harvard University, told Space.com.
Related: Historic First Images of a Black Hole Show Einstein Was Right (Again)
Black hole photo breakthrough
The key to this breakthrough was how the researchers linked radio dishes across the globe to create a virtual telescope effectively about the size of Earth, stretching from the United States to Mexico to Chile to the South Pole.
Ultimately, they succeeded in taking a photo of the silhouette of the supermassive black hole at the center of the nearby galaxy Messier 87.
Although Messier 87 is 2,000 times farther from Earth than Sagittarius A*, its central black hole is more than a thousand times the mass of Sagittarius A*, so it appears about as big in the sky — about the size as an orange on the moon.
“Having the first image of a black hole is a major breakthrough,” Loeb said. “Albert Einstein and Karl Schwarzschild would have been delighted to see this image merely a century after contemplating the modern concept of black holes.”
Currently, there are plans to capture images of more black holes with even greater resolution. In 2017, the Event Horizon Telescope included eight radio observatories, and three more are expected to join by 2020, boosting its power, Loeb said.
In the future, researchers hope to see explosive activity from black holes, such as when they rip a star apart or when they burst with jets of plasma traveling near the speed of light. “But most importantly, we hope to see something unexpected that would revolutionize our views on black holes and the behavior of matter near them,” Loeb said.
First ever image of a black hole
The Commission today revealed the first ever image of a black hole taken by Event Horizon Telescope, a global scientific collaboration involving EU-funded scientists. This major discovery provides visual evidence for the existence of black holes and pushes the boundaries of modern science.
Black holes are extremely compressed cosmic objects, containing incredible amounts of mass within a tiny region.
Their presence affects their surroundings in extreme ways, by warping spacetime and super-heating any material falling into it.
The captured image reveals the black hole at the centre of Messier 87, a massive galaxy in the constellation of Virgo. This black hole is located 55 million light-years from Earth and has a mass 6.5-billion times larger than our sun.
The first ever observation of a black hole is the result of the large scale international research collaboration Event Horizon Telescope (EHT), where EU-funded researchers have played a key role.
This major scientific achievement marks a paradigm shift in our understanding of black holes, confirms the predictions of Albert Einstein's General Theory of Relativity and opens up new lines of enquiry into our universe.
The first image of a black hole successfully captured was unveiled in six simultaneous press conferences across the globe today.
EU funding through the European Research Council (ERC) has provided crucial support to the EHT. In particular, the EU has provided funding for three of the leading scientists and their teams involved in the discovery, as well as supported the development and upgrading of the large telescope infrastructure essential to the success of the project.
Today's results add to the many achievements of the EU's research and innovation funding programmes Horizon 2020 and its predecessor Framework Programmes. Building on this success, the Commission has proposed Horizon Europe, the most ambitious EU programme yet to keep the EU at the forefront of global research and innovation.
- Black hole photos and videos on Commission's audio-visual portal
- Event Horizon Telescope press release
- European Commission press conference on Europe by Satellite
- European Commission press conference on EUtube
The first picture of a black hole opens a new era of astrophysics
This is what a black hole looks like.
A world-spanning network of telescopes called the Event Horizon Telescope zoomed in on the supermassive monster in the galaxy M87 to create this first-ever picture of a black hole.
“We have seen what we thought was unseeable. We have seen and taken a picture of a black hole,” Sheperd Doeleman, EHT Director and astrophysicist at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., said April 10 in Washington, D.C., at one of seven concurrent news conferences. The results were also published in six papers in the Astrophysical Journal Letters.
“We’ve been studying black holes so long, sometimes it’s easy to forget that none of us have actually seen one,” France Córdova, director of the National Science Foundation, said in the Washington, D.C., news conference. Seeing one “is a Herculean task,” she said.
That’s because black holes are notoriously hard to see. Their gravity is so extreme that nothing, not even light, can escape across the boundary at a black hole’s edge, known as the event horizon.
But some black holes, especially supermassive ones dwelling in galaxies’ centers, stand out by voraciously accreting bright disks of gas and other material. The EHT image reveals the shadow of M87’s black hole on its accretion disk.
Appearing as a fuzzy, asymmetrical ring, it unveils for the first time a dark abyss of one of the universe’s most mysterious objects.
“It’s been such a buildup,” Doeleman said. “It was just astonishment and wonder… to know that you’ve uncovered a part of the universe that was off limits to us.”
The much-anticipated big reveal of the image “lives up to the hype, that’s for sure,” says Yale University astrophysicist Priyamvada Natarajan, who is not on the EHT team.
“It really brings home how fortunate we are as a species at this particular time, with the capacity of the human mind to comprehend the universe, to have built all the science and technology to make it happen.” (SN Online: 4/10/19)
It’s Finally here. The First Ever Image of a Black Hole
“We have taken the first picture of a black hole.”
EHT project director Sheperd S. Doeleman of the Center for Astrophysics | Harvard & Smithsonian.
What was once un-seeable can now be seen. Black holes, those difficult-to-understand singularities that may reside at the center of every galaxy, are becoming seeable. The Event Horizon Telescope (EHT) has revealed the first-ever image of a black hole, and with this image, and all the science behind it, they may help crack open one of the biggest mysteries in the Universe.
The black hole in this image resides at the center of M87, a massive galaxy that’s in the Virgo cluster of galaxies. Called M87* (M87-star), it’s a behemoth, at about 6.
5 billion times the mass of the Sun. M87* is about 55 million light years from Earth.
For now we only have this picture of M87*, but pictures of our very own black hole, Sagittarius A* at the center of the Milky Way, are still coming.
This may be the worst kept secret of the past couple weeks. Ever since the EHT said they would be announcing some important results, the excitement has built.
“This is an extraordinary scientific feat accomplished by a team of more than 200 researchers.“
EHT project director Sheperd S. Doeleman of the Center for Astrophysics | Harvard & Smithsonian.
“We have taken the first picture of a black hole,” said EHT project director Sheperd S. Doeleman of the Center for Astrophysics | Harvard & Smithsonian. “This is an extraordinary scientific feat accomplished by a team of more than 200 researchers.“
Darkness Visible, Finally: Astronomers Capture First Ever Image of a Black Hole
Continue reading the main story
Astronomers announced on Wednesday that at last they had captured an image of the unobservable: a black hole, a cosmic abyss so deep and dense that not even light can escape it.
For years, and for all the mounting scientific evidence, black holes have remained marooned in the imaginations of artists and the algorithms of splashy computer models of the kind used in Christopher Nolan's outer-space epic “Interstellar.” Now they are more real than ever.
“We have seen what we thought was unseeable,” said Shep Doeleman, an astronomer at the Harvard-Smithsonian Center for Astrophysics, and director of the effort to capture the image, during a Wednesday news conference in Washington, D.C.
The image, of a lopsided ring of light surrounding a dark circle deep in the heart of a galaxy known as Messier 87, some 55 million light-years away from Earth, resembled the Eye of Sauron, a reminder yet again of the implacable power of nature. It is a smoke ring framing a one-way portal to eternity.
To capture the image, astronomers reached across intergalactic space to Messier 87, or M87, a giant galaxy in the constellation Virgo. There, a black hole several billion times more massive than the sun is unleashing a violent jet of energy some 5,000 light-years into space.
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This is the first ever photo of a black hole
Astronomers around the world celebrated today’s unveiling. “Having spent about 20 years helping to visualize the high-energy universe, I am seeing this silhouette of a black hole. That it happened in my lifetime is incredible,” says Kim Kowal Arcand, visualization and emerging-tech lead for the Chandra Observatory.
“This is to me the cherry on top of an amazing rush of astronomical discovery: moving from what was in the realm of science fiction to science fact.”
The image was created using radio astronomy. Most radio astronomy is done using large dishes that capture radio waves hitting Earth. But creating an image of the black hole required a telescope quite a bit larger. Researchers needed one the size of our planet.
That’s why the Event Horizon Telescope combined measurements from radio observatories on four separate continents.
The array is currently made up of sites in North America, South America, Europe, and Antarctica, with other locations being included over its life cycle.
When all dishes take measurements at the same time, they can be combined into a conglomeration of data, similar to what’s taken on a smaller scale in radio dishes. (Check out a great explainer video that goes into more detail here.)
The information used to make the image revealed today comes primarily from data taken in April 2017.
Over the past two years, researchers have worked to turn that information into the clearest image possible by syncing up the measurements taken concurrently around the world.
In 2018, an observatory in Chile was added to help create a clearer photo, after the initial results that came back were a tad foggy.