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Scientists have long believed that a cosmic beast lurks at the center of our Milky Way galaxy, a supermassive black hole. NPR's Nell Greenfieldboyce reports that researchers have captured their first image of this strange object.
NELL GREENFIELDBOYCE, BYLINE: The image got unveiled at news conferences around the world in places like Mexico City and Tokyo. In Washington, D.C., a crowd of scientists and reporters waited expectantly.
LIA MEDEIROS: We're all just very excited because, you know, this is the black hole that we all kind of grew up learning about, right? This is the black hole that is the most studied black hole, really.
GREENFIELDBOYCE: Lia Medeiros is an astrophysicist at the Institute for Advanced Study. She says it's hard to wrap your mind around a black hole.
MEDEIROS: Because it's not an object in the sense of a planet or a star.
GREENFIELDBOYCE: There's no surfaces or a shape. What there is is a bunch of mass crammed into an infinitesimally small point, and its gravity is relentlessly strong.
MEDEIROS: It has this thing that we call an event horizon, which is not a surface. It's essentially just a distance where, if you cross that distance or that threshold, then you are too close. And you're essentially past the point of no return, and you can never escape the black hole.
GREENFIELDBOYCE: She's a member of an international research team called the Event Horizon Telescope Collaboration. It used a global network of radio telescopes to peer at the very heart of our galaxy, where astronomers knew stars orbited around something, something with 4 million times the mass of our sun. A researcher from the University of Arizona named Feryal Ozel got to do the honors.
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FERYAL OZEL: Today the Event Horizon Telescope is delighted to share with you the first direct image of the gentle giant in the center of our galaxy.
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GREENFIELDBOYCE: The image appeared on a screen. People held up cellphones to take pictures of the picture. It looked like a fuzzy orange doughnut, a ring of hot gases swirling around an unseeable black hole. Michael Johnson is with the Center for Astrophysics - Harvard-Smithsonian and on the research team.
MICHAEL JOHNSON: I remember seeing this and just kind of walking around in a daze. You know, you look at that image, and that hole in the center has 4 million solar masses. That's incredible.
GREENFIELDBOYCE: This image of our galaxy's black hole looks like another image released a few years ago. That black hole in a distant galaxy was way more massive. Scientists will learn more about the weirdness of black holes by comparing these two, but the similarities suggest that Albert Einstein basically got gravity right. Nell Greenfieldboyce, NPR News.
(SOUNDBITE OF THE MIDNIGHT SONG, "THE YEARS (PROLOGUE)") Transcript provided by NPR, Copyright NPR.
