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By David Freeman
Scientists on Wednesday unveiled the first-ever photograph of a black hole, giving humanity a glimpse of a bizarre celestial object that has captivated our imagination for more than a century.
The long-anticipated photo — in which a black hole’s silhouette is visible as a dark patch surrounded by a bright ring — was shown in a series of press briefings held simultaneously in Washington, D.C. and five other cities around the world.
The photo is the product of observations made in April 2017 by the Event Horizon Telescope (EHT), an international consortium that linked eight radio observatories around the world to create a single, Earth-size telescope with enough magnifying might to see what until now has been unseeable.
“For 25 years this was always a dream, a fiction, an expectation,” Heino Falcke, an astronomer at Radboud University in the Netherlands and one of the EHT scientists, told NBC News MACH in an email. “I have seen many beautiful, detailed images of black holes — but all were just simulations,” he added. “This one is so precious, so beautiful, because it is real.”
The photo shows the supermassive black hole at the center of a neighboring galaxy known as Messier 87. The black hole lies about 55 million light-years from Earth and is billions of times more massive than the sun.
Falcke said he was surprised by how large the black hole appears in the photo, adding that it hadn’t been clear that the black hole was big enough to produce a shadow that would be visible to us. “Well, we saw the shadow at the first attempt,” he said. “It really is that large — that blew me away.”
Black holes are super-dense remnants of collapsed stars whose gravitational forces are so strong that no matter or even light can escape once it gets too close. Scientists envisioned “invisible stars” at least as far back as the 18th Century, and Einstein’s theory of general relativity predicted the existence of such objects in 1915 — though the term black hole wasn’t coined until 1967.
Countless black holes are now thought to exist in the universe, including an estimated 100 million in our galaxy alone. Lucky for us, astronomers say none is near enough to Earth to pose a threat.
As the name suggests, black holes themselves are completely black — invisible. But scientists had long believed that radio waves given off by the gas and dust swirling around a distant black hole’s so-called event horizon — the theoretical boundary marking the point beyond which all light and matter pass inexorably into the black hole — would be visible through a sufficiently powerful telescope.
Dramatic as it is, the photo unveiled today may be just a prelude to what’s to come from the EHT.
“As with all great discoveries, this is just the beginning,” said EHT chairman Shep Doeleman.
Falcke said the group wanted to make sharper images as well as movies of gas orbiting black holes, adding, “This is just the first step and we are only scratching the surface.”